/* DistriNet malloc (dnmalloc): a more secure memory allocator. Copyright (C) 2005, Yves Younan, Wouter Joosen, Frank Piessens and Rainer Wichmann The authors can be contacted by: Email: dnmalloc@fort-knox.org Address: #if defined(WITH_TPT) Yves Younan Celestijnenlaan 200A B-3001 Heverlee Belgium This library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version. This library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details. You should have received a copy of the GNU Lesser General Public License along with this library; if not, write to the Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA */ /* Current version: dnmalloc 1.0 */ /* Includes arc4random from OpenBSD, which is under the BDS license */ /* Versions: 0.1-0.5: Proof of concept implementation by Hans Van den Eynden and Yves Younan 0.6-0.7: Bug fixes by Yves Younan 0.8-1.0.beta4: Reimplementation from scratch by Yves Younan 1.0.beta4: Public release 1.0.beta5: Prev_chunkinfo speeded up, was really slow because of the way we did lookups A freechunkinfo region is now freed when it is completely empty and not the current one 1.0 (Rainer Wichmann [support at la dash samhna dot org]): --------------------- Compiler warnings fixed Define REALLOC_ZERO_BYTES_FREES because it's what GNU libc does (and what the standard says) Removed unused code Fix assert(aligned_OK(chunk(newp))); -> assert(aligned_OK(chunk(oldp))); Fix statistics in sYSMALLOc Fix overwrite of av->top in sYSMALLOc Provide own assert(), glibc assert() doesn't work (calls malloc) Fix bug in mEMALIGn(), put remainder in hashtable before calling fREe Remove cfree, independent_cmalloc, independent_comalloc (untested public functions not covered by any standard) Provide posix_memalign (that one is in the standard) Move the malloc_state struct to mmapped memory protected by guard pages Add arc4random function to initialize random canary on startup Implement random canary at end of (re|m)alloced/memaligned buffer, check at free/realloc Remove code conditional on !HAVE_MMAP, since mmap is required anyway. Use standard HAVE_foo macros (as generated by autoconf) instead of LACKS_foo Profiling: Reorder branches in hashtable_add, next_chunkinfo, prev_chunkinfo, hashtable_insert, mALLOc, fREe, request2size, checked_request2size (gcc predicts if{} branch to be taken). Use UNLIKELY macro (gcc __builtin_expect()) where branch reordering would make the code awkward. Portability: Hashtable always covers full 32bit address space to avoid assumptions about memory layout. Portability: Try hard to enforce mapping of mmapped memory into 32bit address space, even on 64bit systems. Portability: Provide a dnmalloc_pthread_init() function, since pthread locking on HP-UX only works if initialized after the application has entered main(). Portability: On *BSD, pthread_mutex_lock is unusable since it calls malloc, use spinlocks instead. Portability: Dynamically detect whether the heap is within 32bit address range (e.g. on Linux x86_64, it isn't). Don't use sbrk() if the heap is mapped to an address outside the 32bit range, since this doesn't work with the hashtable. New macro morecore32bit. Success on: HP-UX 11.11/pthread, Linux/pthread (32/64 bit), FreeBSD/pthread, and Solaris 10 i386/pthread. Fail on: OpenBSD/pthread (in _thread_machdep_save_float_state), might be related to OpenBSD pthread internals (??). Non-treaded version (#undef USE_MALLOC_LOCK) works on OpenBSD. further to 1.0: Valgrind client requests inserted (#define USE_VALGRIND) Fix: malloc_consolidate (nextchunk->fd, nextchunk->bck may be NULL) Portability: minsize = 32 bit on 64bit architecture Minor cleanups Fix: eliminate prototypes for memset, memcpy (they're in string.h) Fix: one more malloc_consolidate segfault There may be some bugs left in this version. please use with caution. */ /* Please read the following papers for documentation: Yves Younan, Wouter Joosen, and Frank Piessens, A Methodology for Designing Countermeasures against Current and Future Code Injection Attacks, Proceedings of the Third IEEE International Information Assurance Workshop 2005 (IWIA2005), College Park, Maryland, U.S.A., March 2005, IEEE, IEEE Press. http://www.fort-knox.org/younany_countermeasures.pdf Yves Younan, Wouter Joosen and Frank Piessens and Hans Van den Eynden. Security of Memory Allocators for C and C++. Technical Report CW419, Departement Computerwetenschappen, Katholieke Universiteit Leuven, July 2005. http://www.fort-knox.org/CW419.pdf */ /* Compile: gcc -fPIC -rdynamic -c -Wall dnmalloc-portable.c "Link": Dynamic: gcc -shared -Wl,-soname,libdnmalloc.so.0 -o libdnmalloc.so.0.0 dnmalloc-portable.o -lc Static: ar -rv libdnmalloc.a dnmalloc-portable.o */ /* dnmalloc is based on dlmalloc 2.7.2 (by Doug Lea (dl@cs.oswego.edu)) dlmalloc was released as public domain and contained the following license: "This is a version (aka dlmalloc) of malloc/free/realloc written by Doug Lea and released to the public domain. Use, modify, and redistribute this code without permission or acknowledgement in any way you wish. Send questions, comments, complaints, performance data, etc to dl@cs.oswego.edu * VERSION 2.7.2 Sat Aug 17 09:07:30 2002 Doug Lea (dl at gee) Note: There may be an updated version of this malloc obtainable at ftp://gee.cs.oswego.edu/pub/misc/malloc.c Check before installing!" */ /* The following preprocessor macros are tested, * and hence should have #define directives: * * HAVE_CONFIG_H Define to #include "config.h" (autoconf-generated) * * HAVE_UNISTD_H Define to #include * * HAVE_SYS_UIO_H Define to #include (for writev) * HAVE_WRITEV Define if the 'writev' function is available * * HAVE_SYS_PARAM_H Define to #include (for pagesize) * * HAVE_MALLOC_H Define to #include (for struct mallinfo2) * * HAVE_FCNTL_H Define to #include * * HAVE_SYS_MMAN_H Define to #include * HAVE_MMAP Define if the 'mmap' function is available. * * HAVE_SCHED_H Define to #include * HAVE_SCHED_YIELD Define id the 'sched_yield' function is available */ /* __STD_C should be nonzero if using ANSI-standard C compiler, a C++ compiler, or a C compiler sufficiently close to ANSI to get away with it. */ #ifdef HAVE_CONFIG_H #include "config.h" #endif #ifdef USE_VALGRIND #include #else #define VALGRIND_FREELIKE_BLOCK(a,b) ((void)0) #define VALGRIND_MALLOCLIKE_BLOCK(a,b,c,d) ((void)0) #define VALGRIND_CREATE_MEMPOOL(a,b,c) ((void)0) #define VALGRIND_MEMPOOL_ALLOC(a,b,c) ((void)0) #define VALGRIND_MEMPOOL_FREE(a,b) ((void)0) #define VALGRIND_DESTROY_MEMPOOL(a) ((void)0) #define VALGRIND_MAKE_MEM_DEFINED(a,b) ((void)0) #define VALGRIND_MAKE_MEM_UNDEFINED(a,b) ((void)0) #define VALGRIND_MAKE_MEM_NOACCESS(a,b) ((void)0) #endif #if defined (__GNUC__) && __GNUC__ > 2 # define LIKELY(expression) (__builtin_expect(!!(expression), 1)) # define UNLIKELY(expression) (__builtin_expect(!!(expression), 0)) # define __attribute_malloc__ __attribute__ ((__malloc__)) #else # define LIKELY(x) (x) # define UNLIKELY(x) (x) # define __attribute_malloc__ /* Ignore */ #endif /* Define HAVE_MREMAP to make realloc() use mremap() to re-allocate large blocks. This is currently only possible on Linux with kernel versions newer than 1.3.77. */ #ifndef HAVE_MREMAP #ifdef linux #define HAVE_MREMAP 1 #define _GNU_SOURCE 1 #else #define HAVE_MREMAP 0 #endif #endif /* HAVE_MREMAP */ #ifndef __STD_C #if defined(__STDC__) || defined(_cplusplus) #define __STD_C 1 #else #define __STD_C 0 #endif #endif /*__STD_C*/ /* Void_t* is the pointer type that malloc should say it returns */ #ifndef Void_t #if (__STD_C || defined(WIN32)) #define Void_t void #else #define Void_t char #endif #endif /*Void_t*/ #if __STD_C #include /* for size_t */ #else #include #endif #if !defined(USE_SYSTEM_MALLOC) #ifdef __cplusplus extern "C" { #endif /* define HAVE_UNISTD_H if your system has a . */ #ifdef HAVE_UNISTD_H #include #endif #ifdef HAVE_SYS_UIO_H #include #endif #include /* needed for malloc_stats */ #include /* needed for optional MALLOC_FAILURE_ACTION */ #include #include #include extern int errno; /* 0: lazy, * 1: medium (assertions compiled in), * 2: high (guard pages at end of hash table and ciregions) * 3: paranoid (guards at end of each allocated chunk, check at free) */ #ifndef PARANOIA #define PARANOIA 9 #endif /* Using assert() with multithreading will cause the code * to deadlock since glibc __assert_fail will call malloc(). * We need our very own assert(). */ typedef void assert_handler_tp(const char * error, const char *file, int line); #if PARANOIA > 0 #ifdef NDEBUG #undef NDEBUG #endif static void default_assert_handler(const char *error, const char *file, int line) { #ifdef HAVE_WRITEV struct iovec iov[5]; char * i1 = "assertion failed ("; char * i3 = "): "; char * i5 = "\n"; int res = 0; char ifile[128]; char ierr[128]; strncpy(ifile, file, sizeof(ifile)); ifile[sizeof(ifile)-1] = '\0'; strncpy(ierr, error, sizeof(ierr)); ierr[sizeof(ierr)-1] = '\0'; iov[0].iov_base = i1; iov[0].iov_len = strlen(i1); iov[1].iov_base = ifile; iov[1].iov_len = strlen(ifile); iov[2].iov_base = i3; iov[2].iov_len = strlen(i3); iov[3].iov_base = ierr; iov[3].iov_len = strlen(ierr); iov[4].iov_base = i5; iov[4].iov_len = strlen(i5); do { res = writev(STDERR_FILENO, iov, 5); } while (res < 0 && errno == EINTR); #else fputs("assertion failed (", stderr); fputs(file, stderr); fputs("): ", stderr); fputs(error, stderr); fputc('\n', stderr); #endif (void) line; abort(); } static assert_handler_tp *assert_handler = default_assert_handler; #define assert(x) \ do { \ if (UNLIKELY(!(x))) { \ assert_handler(#x, __FILE__, __LINE__); \ } \ } while (0) #else static assert_handler_tp *assert_handler = NULL; #ifndef NDEBUG #define NDEBUG #endif #define assert(x) ((void)0) #endif assert_handler_tp *dnmalloc_set_handler(assert_handler_tp *new) { assert_handler_tp *old = assert_handler; assert_handler = new; return old; } #include /* define for debugging */ /* #define DNMALLOC_DEBUG */ /* Do some extra checks? if not, covered by assrt()s */ /* #define DNMALLOC_CHECKS */ /* The unsigned integer type used for comparing any two chunk sizes. This should be at least as wide as size_t, but should not be signed. */ #ifndef CHUNK_SIZE_T #define CHUNK_SIZE_T unsigned long #endif /* The unsigned integer type used to hold addresses when they are are manipulated as integers. Except that it is not defined on all systems, intptr_t would suffice. */ #ifndef PTR_UINT #define PTR_UINT unsigned long #endif /* INTERNAL_SIZE_T is the word-size used for internal bookkeeping of chunk sizes. The default version is the same as size_t. While not strictly necessary, it is best to define this as an unsigned type, even if size_t is a signed type. This may avoid some artificial size limitations on some systems. On a 64-bit machine, you may be able to reduce malloc overhead by defining INTERNAL_SIZE_T to be a 32 bit `unsigned int' at the expense of not being able to handle more than 2^32 of malloced space. If this limitation is acceptable, you are encouraged to set this unless you are on a platform requiring 16byte alignments. In this case the alignment requirements turn out to negate any potential advantages of decreasing size_t word size. Implementors: Beware of the possible combinations of: - INTERNAL_SIZE_T might be signed or unsigned, might be 32 or 64 bits, and might be the same width as int or as long - size_t might have different width and signedness as INTERNAL_SIZE_T - int and long might be 32 or 64 bits, and might be the same width To deal with this, most comparisons and difference computations among INTERNAL_SIZE_Ts should cast them to CHUNK_SIZE_T, being aware of the fact that casting an unsigned int to a wider long does not sign-extend. (This also makes checking for negative numbers awkward.) Some of these casts result in harmless compiler warnings on some systems. */ #ifndef INTERNAL_SIZE_T #define INTERNAL_SIZE_T size_t #endif /* The corresponding word size */ #define SIZE_SZ (sizeof(INTERNAL_SIZE_T)) /* MALLOC_ALIGNMENT is the minimum alignment for malloc'ed chunks. It must be a power of two at least 2 * SIZE_SZ, even on machines for which smaller alignments would suffice. It may be defined as larger than this though. Note however that code and data structures are optimized for the case of 8-byte alignment. */ #ifndef MALLOC_ALIGNMENT #define MALLOC_ALIGNMENT (2 * SIZE_SZ) #endif /* The corresponding bit mask value */ #define MALLOC_ALIGN_MASK (MALLOC_ALIGNMENT - 1) /* REALLOC_ZERO_BYTES_FREES should be set if a call to realloc with zero bytes should be the same as a call to free. Some people think it should. Otherwise, since this malloc returns a unique pointer for malloc(0), so does realloc(p, 0). */ #define REALLOC_ZERO_BYTES_FREES /* TRIM_FASTBINS controls whether free() of a very small chunk can immediately lead to trimming. Setting to true (1) can reduce memory footprint, but will almost always slow down programs that use a lot of small chunks. Define this only if you are willing to give up some speed to more aggressively reduce system-level memory footprint when releasing memory in programs that use many small chunks. You can get essentially the same effect by setting MXFAST to 0, but this can lead to even greater slowdowns in programs using many small chunks. TRIM_FASTBINS is an in-between compile-time option, that disables only those chunks bordering topmost memory from being placed in fastbins. */ #ifndef TRIM_FASTBINS #define TRIM_FASTBINS 0 #endif /* USE_DL_PREFIX will prefix all public routines with the string 'dl'. This is necessary when you only want to use this malloc in one part of a program, using your regular system malloc elsewhere. */ /* #define USE_DL_PREFIX */ /* USE_MALLOC_LOCK causes wrapper functions to surround each callable routine with pthread mutex lock/unlock. USE_MALLOC_LOCK forces USE_PUBLIC_MALLOC_WRAPPERS to be defined */ /* #define USE_MALLOC_LOCK */ /* If USE_PUBLIC_MALLOC_WRAPPERS is defined, every public routine is actually a wrapper function that first calls MALLOC_PREACTION, then calls the internal routine, and follows it with MALLOC_POSTACTION. This is needed for locking, but you can also use this, without USE_MALLOC_LOCK, for purposes of interception, instrumentation, etc. It is a sad fact that using wrappers often noticeably degrades performance of malloc-intensive programs. */ #ifdef USE_MALLOC_LOCK #define USE_PUBLIC_MALLOC_WRAPPERS #else /* #define USE_PUBLIC_MALLOC_WRAPPERS */ #endif /* Two-phase name translation. All of the actual routines are given mangled names. When wrappers are used, they become the public callable versions. When DL_PREFIX is used, the callable names are prefixed. */ #ifndef USE_PUBLIC_MALLOC_WRAPPERS #define cALLOc public_cALLOc #define fREe public_fREe #define mALLOc public_mALLOc #define mEMALIGn public_mEMALIGn #define posix_mEMALIGn public_posix_mEMALIGn #define rEALLOc public_rEALLOc #define vALLOc public_vALLOc #define pVALLOc public_pVALLOc #define mALLINFo2 public_mALLINFo2 #define mALLOPt public_mALLOPt #define mTRIm public_mTRIm #define mSTATs public_mSTATs #define mUSABLe public_mUSABLe #endif #ifdef USE_DL_PREFIX #define public_cALLOc dlcalloc #define public_fREe dlfree #define public_mALLOc dlmalloc #define public_mEMALIGn dlmemalign #define public_posix_mEMALIGn dlposix_memalign #define public_rEALLOc dlrealloc #define public_vALLOc dlvalloc #define public_pVALLOc dlpvalloc #define public_mALLINFo2 dlmallinfo2 #define public_mALLOPt dlmallopt #define public_mTRIm dlmalloc_trim #define public_mSTATs dlmalloc_stats #define public_mUSABLe dlmalloc_usable_size #else /* USE_DL_PREFIX */ #define public_cALLOc calloc #define public_fREe free #define public_mALLOc malloc #define public_mEMALIGn memalign #define public_posix_mEMALIGn posix_memalign #define public_rEALLOc realloc #define public_vALLOc valloc #define public_pVALLOc pvalloc #define public_mALLINFo2 mallinfo2 #define public_mALLOPt mallopt #define public_mTRIm malloc_trim #define public_mSTATs malloc_stats #define public_mUSABLe malloc_usable_size #endif /* USE_DL_PREFIX */ /* HAVE_MEMCPY should be defined if you are not otherwise using ANSI STD C, but still have memcpy and memset in your C library and want to use them in calloc and realloc. Otherwise simple macro versions are defined below. USE_MEMCPY should be defined as 1 if you actually want to have memset and memcpy called. People report that the macro versions are faster than libc versions on some systems. Even if USE_MEMCPY is set to 1, loops to copy/clear small chunks (of <= 36 bytes) are manually unrolled in realloc and calloc. */ #ifndef HAVE_MEMCPY #define HAVE_MEMCPY #endif #ifndef USE_MEMCPY #ifdef HAVE_MEMCPY #define USE_MEMCPY 1 #else #define USE_MEMCPY 0 #endif #endif #if (__STD_C || defined(HAVE_MEMCPY)) #ifdef WIN32 /* On Win32 memset and memcpy are already declared in windows.h */ #else #if __STD_C /* Defined in string.h */ #else Void_t* memset(); Void_t* memcpy(); #endif #endif #endif /* MALLOC_FAILURE_ACTION is the action to take before "return 0" when malloc fails to be able to return memory, either because memory is exhausted or because of illegal arguments. By default, sets errno if running on STD_C platform, else does nothing. */ #ifndef MALLOC_FAILURE_ACTION #if __STD_C #define MALLOC_FAILURE_ACTION \ errno = ENOMEM; #else #define MALLOC_FAILURE_ACTION #endif #endif /* MORECORE-related declarations. By default, rely on sbrk */ #if !defined(HAVE_UNISTD_H) #if !defined(__FreeBSD__) && !defined(__OpenBSD__) && !defined(__NetBSD__) #if __STD_C extern Void_t* sbrk(ptrdiff_t); #else extern Void_t* sbrk(); #endif #endif #endif /* MORECORE_FAILURE is the value returned upon failure of MORECORE as well as mmap. Since it cannot be an otherwise valid memory address, and must reflect values of standard sys calls, you probably ought not try to redefine it. */ #ifndef MORECORE_FAILURE #define MORECORE_FAILURE ((void*)(-1UL)) #endif /* MORECORE is the name of the routine to call to obtain more memory from the system. See below for general guidance on writing alternative MORECORE functions, as well as a version for WIN32 and a sample version for pre-OSX macos. */ #ifndef MORECORE #define MORECORE sbrk #endif /* If MORECORE_CONTIGUOUS is true, take advantage of fact that consecutive calls to MORECORE with positive arguments always return contiguous increasing addresses. This is true of unix sbrk. Even if not defined, when regions happen to be contiguous, malloc will permit allocations spanning regions obtained from different calls. But defining this when applicable enables some stronger consistency checks and space efficiencies. */ #ifndef MORECORE_CONTIGUOUS #define MORECORE_CONTIGUOUS 1 #endif /* Define MORECORE_CANNOT_TRIM if your version of MORECORE cannot release space back to the system when given negative arguments. This is generally necessary only if you are using a hand-crafted MORECORE function that cannot handle negative arguments. */ /* #define MORECORE_CANNOT_TRIM */ /* This malloc requires mmap for heap management data. It is an error if mmap is not available. Additionally, mmap will be used to satisfy large requests. */ #ifndef HAVE_MMAP # error HAVE_MMAP not defined, has your operating system mmap? #endif /* Standard unix mmap using /dev/zero clears memory so calloc doesn't need to. */ #ifndef MMAP_CLEARS #define MMAP_CLEARS 1 #endif /* MMAP_AS_MORECORE_SIZE is the minimum mmap size argument to use if sbrk fails, and mmap is used as a backup (which is done only if HAVE_MMAP). The value must be a multiple of page size. This backup strategy generally applies only when systems have "holes" in address space, so sbrk cannot perform contiguous expansion, but there is still space available on system. On systems for which this is known to be useful (i.e. most linux kernels), this occurs only when programs allocate huge amounts of memory. Between this, and the fact that mmap regions tend to be limited, the size should be large, to avoid too many mmap calls and thus avoid running out of kernel resources. */ #ifndef MMAP_AS_MORECORE_SIZE #define MMAP_AS_MORECORE_SIZE (1024 * 1024) #endif /* The system page size. To the extent possible, this malloc manages memory from the system in page-size units. Note that this value is cached during initialization into a field of malloc_state. So even if malloc_getpagesize is a function, it is only called once. The following mechanics for getpagesize were adapted from bsd/gnu getpagesize.h. If none of the system-probes here apply, a value of 4096 is used, which should be OK: If they don't apply, then using the actual value probably doesn't impact performance. */ #ifndef malloc_getpagesize # ifdef _SC_PAGESIZE /* some SVR4 systems omit an underscore */ # ifndef _SC_PAGE_SIZE # define _SC_PAGE_SIZE _SC_PAGESIZE # endif # endif # ifdef _SC_PAGE_SIZE # define malloc_getpagesize sysconf(_SC_PAGE_SIZE) # else # if defined(BSD) || defined(DGUX) || defined(HAVE_GETPAGESIZE) extern size_t getpagesize(); # define malloc_getpagesize getpagesize() # else # ifdef WIN32 /* use supplied emulation of getpagesize */ # define malloc_getpagesize getpagesize() # else # if defined(HAVE_SYS_PARAM_H) # include # endif # ifdef EXEC_PAGESIZE # define malloc_getpagesize EXEC_PAGESIZE # else # ifdef NBPG # ifndef CLSIZE # define malloc_getpagesize NBPG # else # define malloc_getpagesize (NBPG * CLSIZE) # endif # else # ifdef NBPC # define malloc_getpagesize NBPC # else # ifdef PAGESIZE # define malloc_getpagesize PAGESIZE # else /* just guess */ # define malloc_getpagesize (4096) # endif # endif # endif # endif # endif # endif # endif #endif /* This version of malloc supports the standard SVID/XPG mallinfo2 routine that returns a struct containing usage properties and statistics. It should work on any SVID/XPG compliant system that has a /usr/include/malloc.h defining struct mallinfo2. (If you'd like to install such a thing yourself, cut out the preliminary declarations as described above and below and save them in a malloc.h file. But there's no compelling reason to bother to do this.) The main declaration needed is the mallinfo2 struct that is returned (by-copy) by mallinfo2(). The SVID/XPG malloinfo2 struct contains a bunch of fields that are not even meaningful in this version of malloc. These fields are are instead filled by mallinfo2() with other numbers that might be of interest. HAVE_MALLOC_H should be set if you have a /usr/include/malloc.h file that includes a declaration of struct mallinfo2. If so, it is included; else an SVID2/XPG2 compliant version is declared below. These must be precisely the same for mallinfo2() to work. The original SVID version of this struct, defined on most systems with mallinfo2, declares all fields as size_2. But some others define as unsigned long. If your system defines the fields using a type of different width than listed here, you must #include your system version and #define HAVE_MALLOC_H. */ /* #define HAVE_MALLOC_H */ /* On *BSD, malloc.h is deprecated, and on some *BSD including * it may actually raise an error. */ /* cppcheck-suppress syntaxError */ #if defined(HAVE_MALLOC_H) && !defined(__OpenBSD__) && !defined(__FreeBSD__) && !defined(__NetBSD__) && defined(__GLIBC_PREREQ) && __GLIBC_PREREQ(2, 33) #include #else /* SVID2/XPG mallinfo2 structure */ struct mallinfo2 { size_t arena; /* non-mmapped space allocated from system */ size_t ordblks; /* number of free chunks */ size_t smblks; /* number of fastbin blocks */ size_t hblks; /* number of mmapped regions */ size_t hblkhd; /* space in mmapped regions */ size_t usmblks; /* maximum total allocated space */ size_t fsmblks; /* space available in freed fastbin blocks */ size_t uordblks; /* total allocated space */ size_t fordblks; /* total free space */ size_t keepcost; /* top-most, releasable (via malloc_trim) space */ }; /* SVID/XPG defines four standard parameter numbers for mallopt, normally defined in malloc.h. Only one of these (M_MXFAST) is used in this malloc. The others (M_NLBLKS, M_GRAIN, M_KEEP) don't apply, so setting them has no effect. But this malloc also supports other options in mallopt described below. */ #endif /* ---------- description of public routines ------------ */ /* malloc(size_t n) Returns a pointer to a newly allocated chunk of at least n bytes, or null if no space is available. Additionally, on failure, errno is set to ENOMEM on ANSI C systems. If n is zero, malloc returns a minumum-sized chunk. (The minimum size is 16 bytes on most 32bit systems, and 24 or 32 bytes on 64bit systems.) On most systems, size_t is an unsigned type, so calls with negative arguments are interpreted as requests for huge amounts of space, which will often fail. The maximum supported value of n differs across systems, but is in all cases less than the maximum representable value of a size_t. */ #if __STD_C Void_t* public_mALLOc(size_t) __attribute_malloc__; #else Void_t* public_mALLOc(); #endif /* free(Void_t* p) Releases the chunk of memory pointed to by p, that had been previously allocated using malloc or a related routine such as realloc. It has no effect if p is null. It can have arbitrary (i.e., bad!) effects if p has already been freed. Unless disabled (using mallopt), freeing very large spaces will when possible, automatically trigger operations that give back unused memory to the system, thus reducing program footprint. */ #if __STD_C void public_fREe(Void_t*); #else void public_fREe(); #endif /* calloc(size_t n_elements, size_t element_size); Returns a pointer to n_elements * element_size bytes, with all locations set to zero. */ #if __STD_C Void_t* public_cALLOc(size_t, size_t) __attribute_malloc__; #else Void_t* public_cALLOc(); #endif /* realloc(Void_t* p, size_t n) Returns a pointer to a chunk of size n that contains the same data as does chunk p up to the minimum of (n, p's size) bytes, or null if no space is available. The returned pointer may or may not be the same as p. The algorithm prefers extending p when possible, otherwise it employs the equivalent of a malloc-copy-free sequence. If p is null, realloc is equivalent to malloc. If space is not available, realloc returns null, errno is set (if on ANSI) and p is NOT freed. if n is for fewer bytes than already held by p, the newly unused space is lopped off and freed if possible. Unless the #define REALLOC_ZERO_BYTES_FREES is set, realloc with a size argument of zero (re)allocates a minimum-sized chunk. Large chunks that were internally obtained via mmap will always be reallocated using malloc-copy-free sequences unless the system supports MREMAP (currently only linux). The old unix realloc convention of allowing the last-free'd chunk to be used as an argument to realloc is not supported. */ #if __STD_C Void_t* public_rEALLOc(Void_t*, size_t) __attribute_malloc__; #else Void_t* public_rEALLOc(); #endif /* memalign(size_t alignment, size_t n); Returns a pointer to a newly allocated chunk of n bytes, aligned in accord with the alignment argument. The alignment argument should be a power of two. If the argument is not a power of two, the nearest greater power is used. 8-byte alignment is guaranteed by normal malloc calls, so don't bother calling memalign with an argument of 8 or less. Overreliance on memalign is a sure way to fragment space. */ #if __STD_C Void_t* public_mEMALIGn(size_t, size_t) __attribute_malloc__; #else Void_t* public_mEMALIGn(); #endif /* posix_memalign(void** memptr, size_t alignment, size_t n); Sets *memptr to the address of a newly allocated chunk of n bytes, aligned in accord with the alignment argument. Returns 0 on success, otherwise an error (EINVAL for incorrect alignment, ENOMEM for out of memory). The alignment must be a power of two, and a multiple of sizeof(void *). */ #if __STD_C int public_posix_mEMALIGn(Void_t**, size_t, size_t); #else int public_posix_mEMALIGn(); #endif /* valloc(size_t n); Equivalent to memalign(pagesize, n), where pagesize is the page size of the system. If the pagesize is unknown, 4096 is used. */ #if __STD_C Void_t* public_vALLOc(size_t) __attribute_malloc__; #else Void_t* public_vALLOc(); #endif /* mallopt(int parameter_number, int parameter_value) Sets tunable parameters The format is to provide a (parameter-number, parameter-value) pair. mallopt then sets the corresponding parameter to the argument value if it can (i.e., so long as the value is meaningful), and returns 1 if successful else 0. SVID/XPG/ANSI defines four standard param numbers for mallopt, normally defined in malloc.h. Only one of these (M_MXFAST) is used in this malloc. The others (M_NLBLKS, M_GRAIN, M_KEEP) don't apply, so setting them has no effect. But this malloc also supports four other options in mallopt. See below for details. Briefly, supported parameters are as follows (listed defaults are for "typical" configurations). Symbol param # default allowed param values M_MXFAST 1 64 0-80 (0 disables fastbins) M_TRIM_THRESHOLD -1 256*1024 any (-1U disables trimming) M_TOP_PAD -2 0 any M_MMAP_THRESHOLD -3 256*1024 any (or 0 if no MMAP support) M_MMAP_MAX -4 65536 any (0 disables use of mmap) */ #if __STD_C int public_mALLOPt(int, int); #else int public_mALLOPt(); #endif /* mallinfo2() Returns (by copy) a struct containing various summary statistics: arena: current total non-mmapped bytes allocated from system ordblks: the number of free chunks smblks: the number of fastbin blocks (i.e., small chunks that have been freed but not use resused or consolidated) hblks: current number of mmapped regions hblkhd: total bytes held in mmapped regions usmblks: the maximum total allocated space. This will be greater than current total if trimming has occurred. fsmblks: total bytes held in fastbin blocks uordblks: current total allocated space (normal or mmapped) fordblks: total free space keepcost: the maximum number of bytes that could ideally be released back to system via malloc_trim. ("ideally" means that it ignores page restrictions etc.) Because these fields are ints, but internal bookkeeping may be kept as longs, the reported values may wrap around zero and thus be inaccurate. */ #if __STD_C struct mallinfo2 public_mALLINFo2(void); #else struct mallinfo2 public_mALLINFo2(); #endif /* pvalloc(size_t n); Equivalent to valloc(minimum-page-that-holds(n)), that is, round up n to nearest pagesize. */ #if __STD_C Void_t* public_pVALLOc(size_t) __attribute_malloc__; #else Void_t* public_pVALLOc(); #endif /* malloc_trim(size_t pad); If possible, gives memory back to the system (via negative arguments to sbrk) if there is unused memory at the `high' end of the malloc pool. You can call this after freeing large blocks of memory to potentially reduce the system-level memory requirements of a program. However, it cannot guarantee to reduce memory. Under some allocation patterns, some large free blocks of memory will be locked between two used chunks, so they cannot be given back to the system. The `pad' argument to malloc_trim represents the amount of free trailing space to leave untrimmed. If this argument is zero, only the minimum amount of memory to maintain internal data structures will be left (one page or less). Non-zero arguments can be supplied to maintain enough trailing space to service future expected allocations without having to re-obtain memory from the system. Malloc_trim returns 1 if it actually released any memory, else 0. On systems that do not support "negative sbrks", it will always rreturn 0. */ #if __STD_C int public_mTRIm(size_t); #else int public_mTRIm(); #endif /* malloc_usable_size(Void_t* p); Returns the number of bytes you can actually use in an allocated chunk, which may be more than you requested (although often not) due to alignment and minimum size constraints. You can use this many bytes without worrying about overwriting other allocated objects. This is not a particularly great programming practice. malloc_usable_size can be more useful in debugging and assertions, for example: p = malloc(n); assert(malloc_usable_size(p) >= 256); */ #if __STD_C size_t public_mUSABLe(Void_t*); #else size_t public_mUSABLe(); #endif /* malloc_stats(); Prints on stderr the amount of space obtained from the system (both via sbrk and mmap), the maximum amount (which may be more than current if malloc_trim and/or munmap got called), and the current number of bytes allocated via malloc (or realloc, etc) but not yet freed. Note that this is the number of bytes allocated, not the number requested. It will be larger than the number requested because of alignment and bookkeeping overhead. Because it includes alignment wastage as being in use, this figure may be greater than zero even when no user-level chunks are allocated. The reported current and maximum system memory can be inaccurate if a program makes other calls to system memory allocation functions (normally sbrk) outside of malloc. malloc_stats prints only the most commonly interesting statistics. More information can be obtained by calling mallinfo2. */ #if __STD_C void public_mSTATs(); #else void public_mSTATs(); #endif /* mallopt tuning options */ /* M_MXFAST is the maximum request size used for "fastbins", special bins that hold returned chunks without consolidating their spaces. This enables future requests for chunks of the same size to be handled very quickly, but can increase fragmentation, and thus increase the overall memory footprint of a program. This malloc manages fastbins very conservatively yet still efficiently, so fragmentation is rarely a problem for values less than or equal to the default. The maximum supported value of MXFAST is 80. You wouldn't want it any higher than this anyway. Fastbins are designed especially for use with many small structs, objects or strings -- the default handles structs/objects/arrays with sizes up to 16 4byte fields, or small strings representing words, tokens, etc. Using fastbins for larger objects normally worsens fragmentation without improving speed. M_MXFAST is set in REQUEST size units. It is internally used in chunksize units, which adds padding and alignment. You can reduce M_MXFAST to 0 to disable all use of fastbins. This causes the malloc algorithm to be a closer approximation of fifo-best-fit in all cases, not just for larger requests, but will generally cause it to be slower. */ /* M_MXFAST is a standard SVID/XPG tuning option, usually listed in malloc.h */ #ifndef M_MXFAST #define M_MXFAST 1 #endif #ifndef DEFAULT_MXFAST #define DEFAULT_MXFAST 64 #endif /* M_TRIM_THRESHOLD is the maximum amount of unused top-most memory to keep before releasing via malloc_trim in free(). Automatic trimming is mainly useful in long-lived programs. Because trimming via sbrk can be slow on some systems, and can sometimes be wasteful (in cases where programs immediately afterward allocate more large chunks) the value should be high enough so that your overall system performance would improve by releasing this much memory. The trim threshold and the mmap control parameters (see below) can be traded off with one another. Trimming and mmapping are two different ways of releasing unused memory back to the system. Between these two, it is often possible to keep system-level demands of a long-lived program down to a bare minimum. For example, in one test suite of sessions measuring the XF86 X server on Linux, using a trim threshold of 128K and a mmap threshold of 192K led to near-minimal long term resource consumption. If you are using this malloc in a long-lived program, it should pay to experiment with these values. As a rough guide, you might set to a value close to the average size of a process (program) running on your system. Releasing this much memory would allow such a process to run in memory. Generally, it's worth it to tune for trimming rather tham memory mapping when a program undergoes phases where several large chunks are allocated and released in ways that can reuse each other's storage, perhaps mixed with phases where there are no such chunks at all. And in well-behaved long-lived programs, controlling release of large blocks via trimming versus mapping is usually faster. However, in most programs, these parameters serve mainly as protection against the system-level effects of carrying around massive amounts of unneeded memory. Since frequent calls to sbrk, mmap, and munmap otherwise degrade performance, the default parameters are set to relatively high values that serve only as safeguards. The trim value must be greater than page size to have any useful effect. To disable trimming completely, you can set to (unsigned long)(-1) Trim settings interact with fastbin (MXFAST) settings: Unless TRIM_FASTBINS is defined, automatic trimming never takes place upon freeing a chunk with size less than or equal to MXFAST. Trimming is instead delayed until subsequent freeing of larger chunks. However, you can still force an attempted trim by calling malloc_trim. Also, trimming is not generally possible in cases where the main arena is obtained via mmap. Note that the trick some people use of mallocing a huge space and then freeing it at program startup, in an attempt to reserve system memory, doesn't have the intended effect under automatic trimming, since that memory will immediately be returned to the system. */ #define M_TRIM_THRESHOLD -1 #ifndef DEFAULT_TRIM_THRESHOLD #define DEFAULT_TRIM_THRESHOLD (256 * 1024) #endif /* M_TOP_PAD is the amount of extra `padding' space to allocate or retain whenever sbrk is called. It is used in two ways internally: * When sbrk is called to extend the top of the arena to satisfy a new malloc request, this much padding is added to the sbrk request. * When malloc_trim is called automatically from free(), it is used as the `pad' argument. In both cases, the actual amount of padding is rounded so that the end of the arena is always a system page boundary. The main reason for using padding is to avoid calling sbrk so often. Having even a small pad greatly reduces the likelihood that nearly every malloc request during program start-up (or after trimming) will invoke sbrk, which needlessly wastes time. Automatic rounding-up to page-size units is normally sufficient to avoid measurable overhead, so the default is 0. However, in systems where sbrk is relatively slow, it can pay to increase this value, at the expense of carrying around more memory than the program needs. */ #define M_TOP_PAD -2 #ifndef DEFAULT_TOP_PAD #define DEFAULT_TOP_PAD (0) #endif /* M_MMAP_THRESHOLD is the request size threshold for using mmap() to service a request. Requests of at least this size that cannot be allocated using already-existing space will be serviced via mmap. (If enough normal freed space already exists it is used instead.) Using mmap segregates relatively large chunks of memory so that they can be individually obtained and released from the host system. A request serviced through mmap is never reused by any other request (at least not directly; the system may just so happen to remap successive requests to the same locations). Segregating space in this way has the benefits that: 1. Mmapped space can ALWAYS be individually released back to the system, which helps keep the system level memory demands of a long-lived program low. 2. Mapped memory can never become `locked' between other chunks, as can happen with normally allocated chunks, which means that even trimming via malloc_trim would not release them. 3. On some systems with "holes" in address spaces, mmap can obtain memory that sbrk cannot. However, it has the disadvantages that: 1. The space cannot be reclaimed, consolidated, and then used to service later requests, as happens with normal chunks. 2. It can lead to more wastage because of mmap page alignment requirements 3. It causes malloc performance to be more dependent on host system memory management support routines which may vary in implementation quality and may impose arbitrary limitations. Generally, servicing a request via normal malloc steps is faster than going through a system's mmap. The advantages of mmap nearly always outweigh disadvantages for "large" chunks, but the value of "large" varies across systems. The default is an empirically derived value that works well in most systems. */ #define M_MMAP_THRESHOLD -3 #ifndef DEFAULT_MMAP_THRESHOLD #define DEFAULT_MMAP_THRESHOLD (256 * 1024) #endif /* M_MMAP_MAX is the maximum number of requests to simultaneously service using mmap. This parameter exists because . Some systems have a limited number of internal tables for use by mmap, and using more than a few of them may degrade performance. The default is set to a value that serves only as a safeguard. Setting to 0 disables use of mmap for servicing large requests. If HAVE_MMAP is not set, the default value is 0, and attempts to set it to non-zero values in mallopt will fail. */ #define M_MMAP_MAX -4 #ifndef DEFAULT_MMAP_MAX #define DEFAULT_MMAP_MAX (65536) #endif #ifdef __cplusplus }; /* end of extern "C" */ #endif /* ======================================================================== To make a fully customizable malloc.h header file, cut everything above this line, put into file malloc.h, edit to suit, and #include it on the next line, as well as in programs that use this malloc. ======================================================================== */ /* #include "malloc.h" */ /* --------------------- public wrappers ---------------------- */ #ifdef USE_PUBLIC_MALLOC_WRAPPERS /* DL_STATIC used to make functions (deep down) consistent * with prototypes (otherwise the prototypes are static * with USE_PUBLIC_MALLOC_WRAPPERS, but the functions aren't). * The gcc compiler doesn't care, but the HP-UX compiler does. */ #define DL_STATIC static /* Declare all routines as internal */ #if __STD_C static Void_t* mALLOc(size_t) __attribute_malloc__; static void fREe(Void_t*); static Void_t* rEALLOc(Void_t*, size_t) __attribute_malloc__; static Void_t* mEMALIGn(size_t, size_t) __attribute_malloc__; static int posix_mEMALIGn(Void_t**, size_t, size_t); static Void_t* vALLOc(size_t) __attribute_malloc__; static Void_t* pVALLOc(size_t) __attribute_malloc__; static Void_t* cALLOc(size_t, size_t) __attribute_malloc__; static int mTRIm(size_t); static size_t mUSABLe(Void_t*); static void mSTATs(); static int mALLOPt(int, int); static struct mallinfo2 mALLINFo2(void); #else static Void_t* mALLOc(); static void fREe(); static Void_t* rEALLOc(); static Void_t* mEMALIGn(); static int posix_mEMALIGn(); static Void_t* vALLOc(); static Void_t* pVALLOc(); static Void_t* cALLOc(); static int mTRIm(); static size_t mUSABLe(); static void mSTATs(); static int mALLOPt(); static struct mallinfo2 mALLINFo2(); #endif /* MALLOC_PREACTION and MALLOC_POSTACTION should be defined to return 0 on success, and nonzero on failure. The return value of MALLOC_POSTACTION is currently ignored in wrapper functions since there is no reasonable default action to take on failure. */ #ifdef USE_MALLOC_LOCK # ifdef WIN32 static int mALLOC_MUTEx; #define MALLOC_PREACTION slwait(&mALLOC_MUTEx) #define MALLOC_POSTACTION slrelease(&mALLOC_MUTEx) int dnmalloc_pthread_init(void) { return 0; } # elif defined(__NetBSD__) || defined(__OpenBSD__) || defined(__FreeBSD__) # if defined(__NetBSD__) #include extern int __isthreaded; static mutex_t thread_lock = MUTEX_INITIALIZER; #define _MALLOC_LOCK() if (__isthreaded) mutex_lock(&thread_lock) #define _MALLOC_UNLOCK() if (__isthreaded) mutex_unlock(&thread_lock) void _malloc_prefork(void) { _MALLOC_LOCK(); } void _malloc_postfork(void) { _MALLOC_UNLOCK(); } # endif # if defined(__OpenBSD__) extern int __isthreaded; void _thread_malloc_lock(void); void _thread_malloc_unlock(void); #define _MALLOC_LOCK() if (__isthreaded) _thread_malloc_lock() #define _MALLOC_UNLOCK() if (__isthreaded) _thread_malloc_unlock() # endif # if defined(__FreeBSD__) extern int __isthreaded; struct _spinlock { volatile long access_lock; volatile long lock_owner; volatile char *fname; volatile int lineno; }; typedef struct _spinlock spinlock_t; #define _SPINLOCK_INITIALIZER { 0, 0, 0, 0 } void _spinlock(spinlock_t *); void _spinunlock(spinlock_t *); /* # include "/usr/src/lib/libc/include/spinlock.h" */ static spinlock_t thread_lock = _SPINLOCK_INITIALIZER; spinlock_t *__malloc_lock = &thread_lock; #define _MALLOC_LOCK() if (__isthreaded) _spinlock(&thread_lock) #define _MALLOC_UNLOCK() if (__isthreaded) _spinunlock(&thread_lock) # endif /* Common for all three *BSD */ static int malloc_active = 0; static int dnmalloc_mutex_lock() { _MALLOC_LOCK(); if (!malloc_active) { ++malloc_active; return 0; } assert(malloc_active == 0); _MALLOC_UNLOCK(); errno = EDEADLK; return 1; } static int dnmalloc_mutex_unlock() { --malloc_active; _MALLOC_UNLOCK(); return 0; } #define MALLOC_PREACTION dnmalloc_mutex_lock() #define MALLOC_POSTACTION dnmalloc_mutex_unlock() int dnmalloc_pthread_init(void) { return 0; } # else /* Wrapping malloc with pthread_mutex_lock/pthread_mutex_unlock * * Works fine on linux (no malloc in pthread_mutex_lock) * Works with on HP-UX if initialized after entering main() */ #include static int malloc_active = 0; void dnmalloc_fork_prepare(void); void dnmalloc_fork_parent(void); void dnmalloc_fork_child(void); #if !defined(__linux__) static pthread_mutex_t mALLOC_MUTEx; pthread_once_t dnmalloc_once_control = PTHREAD_ONCE_INIT; static int dnmalloc_use_mutex = 0; static void dnmalloc_pthread_init_int(void) { pthread_mutexattr_t mta; pthread_mutexattr_init(&mta); pthread_mutexattr_settype(&mta, PTHREAD_MUTEX_RECURSIVE); pthread_mutex_init(&(mALLOC_MUTEx), &mta); pthread_mutexattr_destroy(&mta); pthread_atfork(dnmalloc_fork_prepare, dnmalloc_fork_parent, dnmalloc_fork_child); dnmalloc_use_mutex = 1; } int dnmalloc_pthread_init(void) { return pthread_once(&dnmalloc_once_control, dnmalloc_pthread_init_int); } #else static pthread_mutex_t mALLOC_MUTEx = PTHREAD_MUTEX_INITIALIZER; static int dnmalloc_use_mutex = 1; int dnmalloc_pthread_init(void) { return pthread_atfork(dnmalloc_fork_prepare, dnmalloc_fork_parent, dnmalloc_fork_child); } #endif /* !defined(__linux__) */ void dnmalloc_fork_prepare(void) { if (dnmalloc_use_mutex) pthread_mutex_lock(&mALLOC_MUTEx); } void dnmalloc_fork_parent(void) { if (dnmalloc_use_mutex) pthread_mutex_unlock(&mALLOC_MUTEx); } void dnmalloc_fork_child(void) { int rc = 0; #ifdef __GLIBC__ if (dnmalloc_use_mutex) { pthread_mutex_unlock (&mALLOC_MUTEx); pthread_mutex_destroy(&mALLOC_MUTEx); rc = pthread_mutex_init(&mALLOC_MUTEx, NULL); } #else if (dnmalloc_use_mutex) rc = pthread_mutex_unlock(&mALLOC_MUTEx); #endif if (rc != 0) { fputs("fork_child failed", stderr); _exit(EXIT_FAILURE); } } static int dnmalloc_mutex_lock(pthread_mutex_t *mutex) { if (dnmalloc_use_mutex) { int rc = pthread_mutex_lock(mutex); if (rc == 0) { if (!malloc_active) { ++malloc_active; return 0; } assert(malloc_active == 0); (void) pthread_mutex_unlock(mutex); errno = EDEADLK; return 1; } return rc; } return 0; } static int dnmalloc_mutex_unlock(pthread_mutex_t *mutex) { if (dnmalloc_use_mutex) { --malloc_active; return pthread_mutex_unlock(mutex); } return 0; } # define MALLOC_PREACTION dnmalloc_mutex_lock(&mALLOC_MUTEx) # define MALLOC_POSTACTION dnmalloc_mutex_unlock(&mALLOC_MUTEx) # endif #else /* Substitute anything you like for these */ # define MALLOC_PREACTION (0) # define MALLOC_POSTACTION (0) int dnmalloc_pthread_init(void) { return 0; } #endif /* USE_MALLOC_LOCK */ Void_t* public_mALLOc(size_t bytes) { Void_t* m; if (MALLOC_PREACTION == 0) { m = mALLOc(bytes); (void) MALLOC_POSTACTION; return m; } return 0; } void public_fREe(Void_t* m) { if (MALLOC_PREACTION == 0) { fREe(m); (void) MALLOC_POSTACTION; } } Void_t* public_rEALLOc(Void_t* m, size_t bytes) { if (MALLOC_PREACTION == 0) { m = rEALLOc(m, bytes); (void) MALLOC_POSTACTION; return m; } return 0; } Void_t* public_mEMALIGn(size_t alignment, size_t bytes) { Void_t* m; if (MALLOC_PREACTION == 0) { m = mEMALIGn(alignment, bytes); (void) MALLOC_POSTACTION; return m; } return 0; } int public_posix_mEMALIGn(Void_t**memptr, size_t alignment, size_t bytes) { int m, ret; if ((ret = MALLOC_PREACTION) == 0) { m = posix_mEMALIGn(memptr, alignment, bytes); (void) MALLOC_POSTACTION; return m; } return ret; } Void_t* public_vALLOc(size_t bytes) { Void_t* m; if (MALLOC_PREACTION == 0) { m = vALLOc(bytes); (void) MALLOC_POSTACTION; return m; } return 0; } Void_t* public_pVALLOc(size_t bytes) { Void_t* m; if (MALLOC_PREACTION == 0) { m = pVALLOc(bytes); (void) MALLOC_POSTACTION; return m; } return 0; } Void_t* public_cALLOc(size_t n, size_t elem_size) { Void_t* m; if (MALLOC_PREACTION == 0) { m = cALLOc(n, elem_size); (void) MALLOC_POSTACTION; return m; } return 0; } int public_mTRIm(size_t s) { int result; if (MALLOC_PREACTION == 0) { result = mTRIm(s); (void) MALLOC_POSTACTION; return result; } return 0; } size_t public_mUSABLe(Void_t* m) { size_t result; if (MALLOC_PREACTION == 0) { result = mUSABLe(m); (void) MALLOC_POSTACTION; return result; } return 0; } void public_mSTATs() { if (MALLOC_PREACTION == 0) { mSTATs(); (void) MALLOC_POSTACTION; } } struct mallinfo2 public_mALLINFo2() { struct mallinfo2 m; if (MALLOC_PREACTION == 0) { m = mALLINFo2(); (void) MALLOC_POSTACTION; return m; } else { struct mallinfo2 nm = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 }; return nm; } } int public_mALLOPt(int p, int v) { int result; if (MALLOC_PREACTION == 0) { result = mALLOPt(p, v); (void) MALLOC_POSTACTION; return result; } return 0; } #else int dnmalloc_pthread_init(void) { return 0; } #define DL_STATIC #endif /* USE_PUBLIC_MALLOC_WRAPPERS */ /* ------------- Optional versions of memcopy ---------------- */ #if USE_MEMCPY /* Note: memcpy is ONLY invoked with non-overlapping regions, so the (usually slower) memmove is not needed. */ #define MALLOC_COPY(dest, src, nbytes) memcpy(dest, src, nbytes) #define MALLOC_ZERO(dest, nbytes) memset(dest, 0, nbytes) #else /* !USE_MEMCPY */ /* Use Duff's device for good zeroing/copying performance. */ #define MALLOC_ZERO(charp, nbytes) \ do { \ INTERNAL_SIZE_T* mzp = (INTERNAL_SIZE_T*)(charp); \ CHUNK_SIZE_T mctmp = (nbytes)/sizeof(INTERNAL_SIZE_T); \ long mcn; \ if (mctmp < 8) mcn = 0; else { mcn = (mctmp-1)/8; mctmp %= 8; } \ switch (mctmp) { \ case 0: for(;;) { *mzp++ = 0; \ case 7: *mzp++ = 0; \ case 6: *mzp++ = 0; \ case 5: *mzp++ = 0; \ case 4: *mzp++ = 0; \ case 3: *mzp++ = 0; \ case 2: *mzp++ = 0; \ case 1: *mzp++ = 0; if(mcn <= 0) break; mcn--; } \ } \ } while(0) #define MALLOC_COPY(dest,src,nbytes) \ do { \ INTERNAL_SIZE_T* mcsrc = (INTERNAL_SIZE_T*) src; \ INTERNAL_SIZE_T* mcdst = (INTERNAL_SIZE_T*) dest; \ CHUNK_SIZE_T mctmp = (nbytes)/sizeof(INTERNAL_SIZE_T); \ long mcn; \ if (mctmp < 8) mcn = 0; else { mcn = (mctmp-1)/8; mctmp %= 8; } \ switch (mctmp) { \ case 0: for(;;) { *mcdst++ = *mcsrc++; \ case 7: *mcdst++ = *mcsrc++; \ case 6: *mcdst++ = *mcsrc++; \ case 5: *mcdst++ = *mcsrc++; \ case 4: *mcdst++ = *mcsrc++; \ case 3: *mcdst++ = *mcsrc++; \ case 2: *mcdst++ = *mcsrc++; \ case 1: *mcdst++ = *mcsrc++; if(mcn <= 0) break; mcn--; } \ } \ } while(0) #endif /* ------------------ MMAP support ------------------ */ #if defined(HAVE_FCNTL_H) #include #endif #if defined(HAVE_SYS_MMAN_H) #include #endif #if !defined(MAP_ANONYMOUS) && defined(MAP_ANON) #define MAP_ANONYMOUS MAP_ANON #endif /* Nearly all versions of mmap support MAP_ANONYMOUS, so the following is unlikely to be needed, but is supplied just in case. */ #ifndef MAP_ANONYMOUS /* rw 19.05.2008 changed to avoid cached file descriptor, untested */ void * anon_mmap (void *addr, size_t length, int prot, int flags) { void * retval = NULL; int dev_zero_fd = -1; /* File descriptor for /dev/zero. */ dev_zero_fd = open("/dev/zero", O_RDWR); if (dev_zero_fd >= 0) { retval = mmap((addr), (size), (prot), (flags), dev_zero_fd, 0); /* closing the file descriptor does not unmap the region */ close(dev_zero_fd); } return retval; } #define MMAP(addr, size, prot, flags) \ (anon_mmap((addr), (size), (prot), (flags))) #else /* have MAP_ANONYMOUS */ #if !defined(MAP_32BIT) && defined(MAP_ADDR32) #define MAP_32BIT MAP_ADDR32 #endif #if defined(MAP_32BIT) #define MMAP(addr, size, prot, flags) \ (mmap((addr), (size), (prot), (flags)|MAP_ANONYMOUS|MAP_32BIT, -1, 0)) #elif defined(__sun) /* * Hint an address within 32bit address space */ #define MMAP(addr, size, prot, flags) \ (mmap((void*)0xC0000000, (size), (prot), (flags)|MAP_ANONYMOUS, -1, 0)) #else /* *BSD */ #define MMAP(addr, size, prot, flags) \ (mmap((void*)0x80000000, (size), (prot), (flags)|MAP_ANONYMOUS, -1, 0)) #endif #endif /* have MAP_ANONYMOUS */ /* ----------------------- Chunk representations ----------------------- */ typedef void * mchunkptr; struct chunkinfo { INTERNAL_SIZE_T prev_size; /* Size of previous in bytes */ INTERNAL_SIZE_T size; /* Size in bytes, including overhead. */ INTERNAL_SIZE_T req; /* Original request size, for guard. */ struct chunkinfo* hash_next; /* contains a pointer to the next chunk in the linked list if the hash value is the same as the chunk */ struct chunkinfo* fd; /* double links -- used only if free. */ struct chunkinfo* bk; mchunkptr chunk; }; typedef struct chunkinfo* chunkinfoptr; struct cireginfo { unsigned long position; unsigned long *freebitmap; struct cireginfo* next; struct chunkinfo *freelist; struct chunkinfo *begin; unsigned long freecounter; }; /* ---------- Size and alignment checks and conversions ---------- */ /* conversion from malloc headers to user pointers, and back */ #define chunk(p) (p->chunk) #define chunk2mem(p) (chunk(p)) #define mem2chunk(mem) (hashtable_lookup(mem)) /* The smallest possible chunk */ /* #define MIN_CHUNK_SIZE 16 */ #if (SIZEOF_UNSIGNED_LONG == 8) || defined(__arch64__) || defined(__ia64__) || defined(__x86_64__) || defined(__LP64__) || defined(__64BIT__) || defined(_LP64) || defined(_M_IA64) || (defined(_MIPS_SZLONG) && (_MIPS_SZLONG == 64)) # define MIN_CHUNK_SIZE 32 #else # define MIN_CHUNK_SIZE 16 #endif /* The smallest size we can malloc is an aligned minimal chunk */ #define MINSIZE \ (CHUNK_SIZE_T)(((MIN_CHUNK_SIZE+MALLOC_ALIGN_MASK) & ~MALLOC_ALIGN_MASK)) /* Check if m has acceptable alignment */ #define aligned_OK(m) (((PTR_UINT)((m)) & (MALLOC_ALIGN_MASK)) == 0) #define GUARD_SIZE 4 /* Check if a request is so large that it would wrap around zero when padded and aligned. To simplify some other code, the bound is made low enough so that adding MINSIZE will also not wrap around zero. Make it 4*MINSIZE. */ #define REQUEST_OUT_OF_RANGE(req) \ ((CHUNK_SIZE_T)(req) >= \ (CHUNK_SIZE_T)(INTERNAL_SIZE_T)(-4 * MINSIZE)) /* pad request bytes into a usable size -- internal version */ #define request2size(req) \ (((req) + GUARD_SIZE + MALLOC_ALIGN_MASK >= MINSIZE) ? \ ((req) + GUARD_SIZE + MALLOC_ALIGN_MASK) & ~MALLOC_ALIGN_MASK :\ MINSIZE) /* Same, except also perform argument check */ #define checked_request2size(req, sz) \ if (!REQUEST_OUT_OF_RANGE(req)) { \ (sz) = request2size(req); \ assert((sz-req) >= GUARD_SIZE); \ } else { \ MALLOC_FAILURE_ACTION; \ return 0; \ } #if PARANOIA > 2 static char * guard_set_p; static char * guard_set_q; #define guard_set(guard, P, request, sz) \ assert((sz-request) >= GUARD_SIZE); \ guard_set_p = (char*)(chunk(P)); \ guard_set_p += request; \ VALGRIND_MAKE_MEM_UNDEFINED(guard_set_p,GUARD_SIZE); \ guard_set_q = (char*)(guard); \ *guard_set_p = *guard_set_q; ++guard_set_p; ++guard_set_q; \ *guard_set_p = *guard_set_q; ++guard_set_p; ++guard_set_q; \ *guard_set_p = *guard_set_q; ++guard_set_p; ++guard_set_q; \ *guard_set_p = *guard_set_q; \ VALGRIND_MAKE_MEM_NOACCESS((((char*)chunk(P))+request),GUARD_SIZE); \ (P)->req = request #define guard_check(guard, P) \ VALGRIND_MAKE_MEM_DEFINED((((char *)chunk(P))+(P)->req), GUARD_SIZE); \ assert(0 == memcmp((((char *)chunk(P))+(P)->req),(void*)(guard),GUARD_SIZE));\ VALGRIND_MAKE_MEM_NOACCESS((((char *)chunk(P))+(P)->req), GUARD_SIZE); #else #define guard_set(guard, P, request, sz) ((void)0) #define guard_check(guard, P) ((void)0) #endif /* PARANOIA > 2 */ /* dnmalloc forward declarations */ static char * dnmalloc_arc4random(void); static void dnmalloc_init (void); static void malloc_mmap_state(void); static void cireg_extend (void); static chunkinfoptr cireg_getfree (void); static void hashtable_add (chunkinfoptr ci); static void hashtable_insert (chunkinfoptr ci_orig, chunkinfoptr ci_insert); static void hashtable_remove (mchunkptr p); static void hashtable_skiprm (chunkinfoptr ci_orig, chunkinfoptr ci_todelete); static chunkinfoptr hashtable_lookup (mchunkptr p); static chunkinfoptr next_chunkinfo (chunkinfoptr ci); static chunkinfoptr prev_chunkinfo (chunkinfoptr ci); /* --------------- Physical chunk operations --------------- */ /* size field is or'ed with PREV_INUSE when previous adjacent chunk in use */ #define PREV_INUSE 0x1 /* extract inuse bit of previous chunk */ #define prev_inuse(p) ((p)->size & PREV_INUSE) /* size field is or'ed with IS_MMAPPED if the chunk was obtained with mmap() */ #define IS_MMAPPED 0x2 /* check for mmap()'ed chunk */ #define chunk_is_mmapped(p) ((p)->size & IS_MMAPPED) /* size field is or'ed when the chunk is in use */ #define INUSE 0x4 /* extract inuse bit of chunk */ #define inuse(p) ((p)->size & INUSE) /* Bits to mask off when extracting size Note: IS_MMAPPED is intentionally not masked off from size field in macros for which mmapped chunks should never be seen. This should cause helpful core dumps to occur if it is tried by accident by people extending or adapting this malloc. */ #define SIZE_BITS (PREV_INUSE|IS_MMAPPED|INUSE) /* Bits to mask off when extracting size of chunks for macros which do not use mmap */ #define SIZE_NOMMAP (PREV_INUSE|INUSE) /* Get size, ignoring use bits */ #define chunksize(p) ((p)->size & ~(SIZE_BITS)) /* Ptr to chunkinfo of next physical malloc_chunk. */ #define next_chunk(p) ((mchunkptr)( ((char*)(p)) + ((p)->size & SIZE_NOMMAP) )) /* Treat space at ptr + offset as a chunk */ #define chunk_at_offset(p, s) ((mchunkptr)(((char*)(p)) + (s))) /* set/clear chunk as being inuse without otherwise disturbing */ #define set_inuse(p) ((p)->size |= INUSE) #define clear_inuse(p) ((p)->size &= ~(INUSE)) #define set_previnuse(p) ((p)->size |= PREV_INUSE) #define clear_previnuse(p) ((p)->size &= ~(PREV_INUSE)) static void set_previnuse_next (chunkinfoptr p) { chunkinfoptr q; q = next_chunkinfo (p); if (q) set_previnuse (q); } #define set_all_inuse(p) \ set_inuse(p); \ set_previnuse_next(p); /* Set size at head, without disturbing its use bit */ #define set_head_size(p, s) ((p)->size = (((p)->size & SIZE_NOMMAP) | (s))) /* Set size/use field */ #define set_head(p, s) ((p)->size = (s)) /* Bins An array of bin headers for free chunks. Each bin is doubly linked. The bins are approximately proportionally (log) spaced. There are a lot of these bins (128). This may look excessive, but works very well in practice. Most bins hold sizes that are unusual as malloc request sizes, but are more usual for fragments and consolidated sets of chunks, which is what these bins hold, so they can be found quickly. All procedures maintain the invariant that no consolidated chunk physically borders another one, so each chunk in a list is known to be preceeded and followed by either inuse chunks or the ends of memory. Chunks in bins are kept in size order, with ties going to the approximately least recently used chunk. Ordering isn't needed for the small bins, which all contain the same-sized chunks, but facilitates best-fit allocation for larger chunks. These lists are just sequential. Keeping them in order almost never requires enough traversal to warrant using fancier ordered data structures. Chunks of the same size are linked with the most recently freed at the front, and allocations are taken from the back. This results in LRU (FIFO) allocation order, which tends to give each chunk an equal opportunity to be consolidated with adjacent freed chunks, resulting in larger free chunks and less fragmentation. To simplify use in double-linked lists, each bin header acts as a malloc_chunk. This avoids special-casing for headers. But to conserve space and improve locality, we allocate only the fd/bk pointers of bins, and then use repositioning tricks to treat these as the fields of a malloc_chunk*. */ typedef struct chunkinfo* mbinptr; /* addressing -- note that bin_at(0) does not exist */ #define bin_at(m, i) (&(m)->bins[i]) /* analog of ++bin */ #define next_bin(b) (b+1) /* Reminders about list directionality within bins */ #define first(b) ((b)->fd) #define last(b) ((b)->bk) /* Take a chunk off a bin list */ #define unlink(P, BK, FD) { \ FD = P->fd; \ BK = P->bk; \ FD->bk = BK; \ BK->fd = FD; \ } /* Indexing Bins for sizes < 512 bytes contain chunks of all the same size, spaced 8 bytes apart. Larger bins are approximately logarithmically spaced: 64 bins of size 8 32 bins of size 64 16 bins of size 512 8 bins of size 4096 4 bins of size 32768 2 bins of size 262144 1 bin of size what's left The bins top out around 1MB because we expect to service large requests via mmap. */ #define NBINS 96 #define NSMALLBINS 32 #define SMALLBIN_WIDTH 8 #define MIN_LARGE_SIZE 256 #define in_smallbin_range(sz) \ ((CHUNK_SIZE_T)(sz) < (CHUNK_SIZE_T)MIN_LARGE_SIZE) #define smallbin_index(sz) (((unsigned)(sz)) >> 3) /* Compute index for size. We expect this to be inlined when compiled with optimization, else not, which works out well. */ static int largebin_index(size_t sz) { unsigned long xx = sz >> SMALLBIN_WIDTH; if (xx < 0x10000) { unsigned int m; /* bit position of highest set bit of m */ /* On intel, use BSRL instruction to find highest bit */ #if defined(__GNUC__) && defined(i386) && !defined(USE_UNO) unsigned int x = (unsigned int) xx; __asm__("bsrl %1,%0\n\t" : "=r" (m) : "rm" (x)); #elif defined(__GNUC__) && defined(x86_64) && !defined(USE_UNO) __asm__("bsrq %1,%0\n\t" : "=r" (m) : "rm" (xx)); #else /* Taken from Bit Twiddling Hacks * http://graphics.stanford.edu/~seander/bithacks.html * public domain */ unsigned int v = (unsigned int) xx; register unsigned int shift; m = (v > 0xFFFF) << 4; v >>= m; shift = (v > 0xFF ) << 3; v >>= shift; m |= shift; shift = (v > 0xF ) << 2; v >>= shift; m |= shift; shift = (v > 0x3 ) << 1; v >>= shift; m |= shift; m |= (v >> 1); #endif /* Use next 2 bits to create finer-granularity bins */ return NSMALLBINS + (m << 2) + ((sz >> (m + 6)) & 3); } else { return NBINS-1; } } #define bin_index(sz) \ ((in_smallbin_range(sz)) ? smallbin_index(sz) : largebin_index(sz)) /* FIRST_SORTED_BIN_SIZE is the chunk size corresponding to the first bin that is maintained in sorted order. This must be the smallest size corresponding to a given bin. Normally, this should be MIN_LARGE_SIZE. But you can weaken best fit guarantees to sometimes speed up malloc by increasing value. Doing this means that malloc may choose a chunk that is non-best-fitting by up to the width of the bin. Some useful cutoff values: 512 - all bins sorted 2560 - leaves bins <= 64 bytes wide unsorted 12288 - leaves bins <= 512 bytes wide unsorted 65536 - leaves bins <= 4096 bytes wide unsorted 262144 - leaves bins <= 32768 bytes wide unsorted -1 - no bins sorted (not recommended!) */ /* #define FIRST_SORTED_BIN_SIZE 65536 */ #define FIRST_SORTED_BIN_SIZE MIN_LARGE_SIZE /* Unsorted chunks All remainders from chunk splits, as well as all returned chunks, are first placed in the "unsorted" bin. They are then placed in regular bins after malloc gives them ONE chance to be used before binning. So, basically, the unsorted_chunks list acts as a queue, with chunks being placed on it in free (and malloc_consolidate), and taken off (to be either used or placed in bins) in malloc. */ /* The otherwise unindexable 1-bin is used to hold unsorted chunks. */ #define unsorted_chunks(M) (bin_at(M, 1)) /* Top The top-most available chunk (i.e., the one bordering the end of available memory) is treated specially. It is never included in any bin, is used only if no other chunk is available, and is released back to the system if it is very large (see M_TRIM_THRESHOLD). Because top initially points to its own bin with initial zero size, thus forcing extension on the first malloc request, we avoid having any special code in malloc to check whether it even exists yet. But we still need to do so when getting memory from system, so we make initial_top treat the bin as a legal but unusable chunk during the interval between initialization and the first call to sYSMALLOc. (This is somewhat delicate, since it relies on the 2 preceding words to be zero during this interval as well.) */ /* Conveniently, the unsorted bin can be used as dummy top on first call */ #define initial_top(M) (unsorted_chunks(M)) /* Binmap To help compensate for the large number of bins, a one-level index structure is used for bin-by-bin searching. `binmap' is a bitvector recording whether bins are definitely empty so they can be skipped over during during traversals. The bits are NOT always cleared as soon as bins are empty, but instead only when they are noticed to be empty during traversal in malloc. */ /* Conservatively use 32 bits per map word, even if on 64bit system */ #define BINMAPSHIFT 5 #define BITSPERMAP (1U << BINMAPSHIFT) #define BINMAPSIZE (NBINS / BITSPERMAP) #define idx2block(i) ((i) >> BINMAPSHIFT) #define idx2bit(i) ((1U << ((i) & ((1U << BINMAPSHIFT)-1)))) #define mark_bin(m,i) ((m)->binmap[idx2block(i)] |= idx2bit(i)) #define unmark_bin(m,i) ((m)->binmap[idx2block(i)] &= ~(idx2bit(i))) #define get_binmap(m,i) ((m)->binmap[idx2block(i)] & idx2bit(i)) /* Fastbins An array of lists holding recently freed small chunks. Fastbins are not doubly linked. It is faster to single-link them, and since chunks are never removed from the middles of these lists, double linking is not necessary. Also, unlike regular bins, they are not even processed in FIFO order (they use faster LIFO) since ordering doesn't much matter in the transient contexts in which fastbins are normally used. Chunks in fastbins keep their inuse bit set, so they cannot be consolidated with other free chunks. malloc_consolidate releases all chunks in fastbins and consolidates them with other free chunks. */ typedef struct chunkinfo* mfastbinptr; /* offset 2 to use otherwise unindexable first 2 bins */ #define fastbin_index(sz) ((((unsigned int)(sz)) >> 3) - 2) /* The maximum fastbin request size we support */ #define MAX_FAST_SIZE 80 #define NFASTBINS (fastbin_index(request2size(MAX_FAST_SIZE))+1) /* FASTBIN_CONSOLIDATION_THRESHOLD is the size of a chunk in free() that triggers automatic consolidation of possibly-surrounding fastbin chunks. This is a heuristic, so the exact value should not matter too much. It is defined at half the default trim threshold as a compromise heuristic to only attempt consolidation if it is likely to lead to trimming. However, it is not dynamically tunable, since consolidation reduces fragmentation surrounding loarge chunks even if trimming is not used. */ #define FASTBIN_CONSOLIDATION_THRESHOLD \ ((unsigned long)(DEFAULT_TRIM_THRESHOLD) >> 1) /* Since the lowest 2 bits in max_fast don't matter in size comparisons, they are used as flags. */ /* ANYCHUNKS_BIT held in max_fast indicates that there may be any freed chunks at all. It is set true when entering a chunk into any bin. */ #define ANYCHUNKS_BIT (1U) #define have_anychunks(M) (((M)->max_fast & ANYCHUNKS_BIT)) #define set_anychunks(M) ((M)->max_fast |= ANYCHUNKS_BIT) #define clear_anychunks(M) ((M)->max_fast &= ~ANYCHUNKS_BIT) /* FASTCHUNKS_BIT held in max_fast indicates that there are probably some fastbin chunks. It is set true on entering a chunk into any fastbin, and cleared only in malloc_consolidate. */ #define FASTCHUNKS_BIT (2U) #define have_fastchunks(M) (((M)->max_fast & FASTCHUNKS_BIT)) #define set_fastchunks(M) ((M)->max_fast |= (FASTCHUNKS_BIT|ANYCHUNKS_BIT)) #define clear_fastchunks(M) ((M)->max_fast &= ~(FASTCHUNKS_BIT)) /* Set value of max_fast. Use impossibly small value if 0. */ #define set_max_fast(M, s) \ (M)->max_fast = (((s) == 0)? SMALLBIN_WIDTH: request2size(s)) | \ ((M)->max_fast & (FASTCHUNKS_BIT|ANYCHUNKS_BIT)) #define get_max_fast(M) \ ((M)->max_fast & ~(FASTCHUNKS_BIT | ANYCHUNKS_BIT)) /* morecore_properties is a status word holding dynamically discovered or controlled properties of the morecore function */ #define MORECORE_CONTIGUOUS_BIT (1U) #define contiguous(M) \ (((M)->morecore_properties & MORECORE_CONTIGUOUS_BIT)) #define noncontiguous(M) \ (((M)->morecore_properties & MORECORE_CONTIGUOUS_BIT) == 0) #define set_contiguous(M) \ ((M)->morecore_properties |= MORECORE_CONTIGUOUS_BIT) #define set_noncontiguous(M) \ ((M)->morecore_properties &= ~MORECORE_CONTIGUOUS_BIT) #define MORECORE_32BIT_BIT (2U) #define morecore32bit(M) \ (((M)->morecore_properties & MORECORE_32BIT_BIT)) #define nonmorecore32bit(M) \ (((M)->morecore_properties & MORECORE_32BIT_BIT) == 0) #define set_morecore32bit(M) \ ((M)->morecore_properties |= MORECORE_32BIT_BIT) #define set_nonmorecore32bit(M) \ ((M)->morecore_properties &= ~MORECORE_32BIT_BIT) /* ----------------- dnmalloc -------------------- */ /* size of pages */ #define PGSIZE malloc_getpagesize /* pointer size */ #define PTRSIZE sizeof(long) /* TODO: mmapped chunks are always multiples of pagesize -> we're wasting address space: the hashtable has granularity of 16*8, set it to something closer to pagesize for mmapped chunks (current waste: 32 positions/mmapped page) */ /* The maximum heap size that dnmalloc can operate with * represented in hex to avoid annoying gcc warning * * Avoid integer overflow, cover complete 32bit address * space for portability. With deferred allocation, the * hashtable size is a non-issue. */ #define HEAPMAXSIZE_HALF 0x80000000UL /* How many elements are stored in the linked list */ #define LINKEDLSTELS 8 /* Minimum size of a chunk */ #if (SIZEOF_UNSIGNED_LONG == 8) || defined(__arch64__) || defined(__ia64__) || defined(__x86_64__) || defined(__LP64__) || defined(__64BIT__) || defined(_LP64) || defined(_M_IA64) || (defined(_MIPS_SZLONG) && (_MIPS_SZLONG == 64)) # define MINCHUNKSIZE 32 #else # define MINCHUNKSIZE 16 #endif /* The amount of hashtable entries for each page: Pagesize divded by the numer of elements in the linkedlists divided by the minimum chunk size */ #define CHUNKINFOPAGE (PGSIZE / LINKEDLSTELS / MINCHUNKSIZE) /* The amount of hashtable entries needed to manage the memory: Maximum heap size divided by page size multiplied by the amount of chunk info's per page */ #define AMOUNTHASH ((HEAPMAXSIZE_HALF / PGSIZE) * CHUNKINFOPAGE * 2) /* Initial size of the map for the hashtable Amount of entries muliplied by pointer size */ #define HASHTABLESIZE (AMOUNTHASH * PTRSIZE) /* Amount of free chunks that the system should allocate at the start */ #define NUMBER_FREE_CHUNKS 32768 /* Initial size of the chunk info region, also used when growing the region */ #define CIREGSIZE (NUMBER_FREE_CHUNKS * sizeof(struct chunkinfo)) /* Start address of the heap */ char *startheap; /* pointer to the hashtable: struct chunkinfo **hashtable -> *hashtable[] */ chunkinfoptr *hashtable; /* Current chunkinfo region */ struct cireginfo *currciinfo = 0; struct cireginfo *firstciinfo = 0; unsigned long totalcictr = 0; /* Initialize the area for chunkinfos and the hashtable and protect * it with non-writable pages */ static void dnmalloc_init () { void *hashtb; int mprot; int flags = MAP_PRIVATE; /* Allocate the malloc_state struct */ malloc_mmap_state(); /* Use MAP_NORESERVE if available (Solaris, HP-UX; most other * systems use defered allocation anyway. */ #ifdef MAP_NORESERVE flags |= MAP_NORESERVE; #endif /* Always start at 0, hashtable covers whole 32bit address space */ #define STARTHEAP_IS_ZERO startheap = 0; /* Map space for the hashtable */ #if PARANOIA > 1 hashtb = MMAP(0, HASHTABLESIZE+(2*PGSIZE), PROT_READ|PROT_WRITE, flags); #else hashtb = MMAP(0, HASHTABLESIZE+PGSIZE, PROT_READ|PROT_WRITE, flags); #endif #ifdef NDEBUG if (hashtb == MAP_FAILED) { fprintf (stderr, "Couldn't mmap hashtable: %s\n", strerror (errno)); abort (); } #else assert(hashtb != MAP_FAILED); #endif /* Protect the hashtable with non-writable pages */ mprot = mprotect(hashtb, (size_t) PGSIZE, PROT_NONE); #ifdef NDEBUG if (mprot == -1) { fprintf (stderr, "Couldn't mprotect first non-rw page for hashtable: %s\n", strerror (errno)); abort (); } #else assert(mprot != -1); #endif /* HP-UX: Cannot do arithmetic with pointers to objects of unknown size. */ hashtable = (chunkinfoptr *) (((char*)hashtb) + PGSIZE); /* Protect the hashtable with non-writable pages */ #if PARANOIA > 1 mprot = mprotect((void*)((char*)hashtb+HASHTABLESIZE+PGSIZE), (size_t) PGSIZE, PROT_NONE); #ifdef NDEBUG if (mprot == -1) { fprintf (stderr, "Couldn't mprotect last non-rw page for hashtable: %s\n", strerror (errno)); abort (); } #else assert(mprot != -1); #endif #endif } /* Extend the region for chunk infos by mapping more memory before the region */ static void cireg_extend () { void *newcireg; int mprot; struct cireginfo *tempciinfo = 0; #if PARANOIA > 1 newcireg = MMAP(0, CIREGSIZE+(2*PGSIZE), PROT_READ|PROT_WRITE, MAP_PRIVATE); #else newcireg = MMAP(0, CIREGSIZE+PGSIZE, PROT_READ|PROT_WRITE, MAP_PRIVATE); #endif #ifdef NDEBUG if (newcireg == MAP_FAILED) { fprintf (stderr, "Couldn't extend chunkinfo region: %s\n", strerror (errno)); abort (); } #else assert(newcireg != MAP_FAILED); #endif mprot = mprotect(newcireg, PGSIZE, PROT_NONE); #ifdef NDEBUG if (mprot == -1) { fprintf (stderr, "Couldn't mprotect first non-rw page for extended region: %s\n", strerror (errno)); abort (); } #else assert(mprot != -1); #endif newcireg = ((char*)newcireg)+PGSIZE; #if PARANOIA > 1 mprot = mprotect((void*)((char*)newcireg+CIREGSIZE), (size_t) PGSIZE, PROT_NONE); #ifdef NDEBUG if (mprot == -1) { fprintf (stderr, "Couldn't mprotect last non-rw page for extended region: %s\n", strerror (errno)); abort (); } #else assert(mprot != -1); #endif #endif tempciinfo = currciinfo; currciinfo = (struct cireginfo *) newcireg; if (tempciinfo) tempciinfo->next = currciinfo; currciinfo->position = 1; currciinfo->freecounter = NUMBER_FREE_CHUNKS; if (!firstciinfo) firstciinfo = currciinfo; totalcictr++; VALGRIND_CREATE_MEMPOOL(newcireg, 0, 0); } /* Get a free chunkinfo */ static chunkinfoptr cireg_getfree () { chunkinfoptr freeci; chunkinfoptr freelst = 0; struct cireginfo *newciinfo = firstciinfo; if (newciinfo) { freelst = newciinfo->freelist; if (!freelst && newciinfo->next) { do { newciinfo = newciinfo->next; freelst = newciinfo->freelist; } while (!freelst && newciinfo->next); } } /* Check if there are any free chunkinfos on the list of free chunkinfos */ if (freelst) { freeci = freelst; newciinfo->freecounter--; newciinfo->freelist = freelst->fd; VALGRIND_MEMPOOL_ALLOC((char*)currciinfo, (char*)freeci, sizeof(struct chunkinfo)); freeci->prev_size = 0; freeci->size = 0; freeci->req = 0; freeci->hash_next = NULL; freeci->fd = NULL; freeci->bk = NULL; freeci->chunk = NULL; return (freeci); } else { /* No free chunkinfos, check if chunkinfo region still has place * for a chunkinfo. If not, extend the region. */ if (UNLIKELY(!currciinfo || currciinfo->position == NUMBER_FREE_CHUNKS)) cireg_extend (); /* Get a chunkinfo from the chunkinfo region */ freeci = (chunkinfoptr) currciinfo + currciinfo->position; currciinfo->freecounter--; currciinfo->position++; VALGRIND_MEMPOOL_ALLOC((char*)currciinfo, (char*)freeci, sizeof(struct chunkinfo)); return (freeci); } } static void freeciregion(struct cireginfo *freeme) { /* free the chunkinfo region */ struct cireginfo *newciinfo = firstciinfo; struct cireginfo *prevciinfo = firstciinfo; void *unmapme; while (newciinfo && newciinfo != freeme) { prevciinfo = newciinfo; newciinfo = newciinfo->next; } assert(freeme == newciinfo); /* rw */ assert(newciinfo != NULL); /* rw */ if (newciinfo) prevciinfo->next = newciinfo->next; unmapme = (void *) ((char*)freeme - PGSIZE); VALGRIND_DESTROY_MEMPOOL((char*)freeme); #if PARANOIA > 1 munmap(unmapme, CIREGSIZE+(2*PGSIZE)); #else munmap(unmapme, CIREGSIZE+PGSIZE); #endif } static void freecilst_add(chunkinfoptr p) { struct cireginfo *newciinfo; newciinfo = currciinfo; if (((chunkinfoptr) newciinfo < p) && (p < (chunkinfoptr) (newciinfo+NUMBER_FREE_CHUNKS))) { p->fd = newciinfo->freelist; newciinfo->freelist = p; newciinfo->freecounter++; VALGRIND_MEMPOOL_FREE((char*)newciinfo, (char*)p); VALGRIND_MAKE_MEM_DEFINED(p,sizeof(struct chunkinfo)); VALGRIND_MAKE_MEM_NOACCESS(p->size, sizeof(INTERNAL_SIZE_T)); VALGRIND_MAKE_MEM_NOACCESS(p->req, sizeof(INTERNAL_SIZE_T)); VALGRIND_MAKE_MEM_NOACCESS(p->bk, sizeof(struct chunkinfo*)); VALGRIND_MAKE_MEM_NOACCESS(p->chunk, sizeof(mchunkptr)); } else { newciinfo = firstciinfo; if (newciinfo) { do { if (((chunkinfoptr) newciinfo < p) && (p < (chunkinfoptr) (newciinfo+NUMBER_FREE_CHUNKS))) { p->fd = newciinfo->freelist; newciinfo->freelist = p; newciinfo->freecounter++; VALGRIND_MEMPOOL_FREE((char*)newciinfo, (char*)p); VALGRIND_MAKE_MEM_DEFINED(p,sizeof(struct chunkinfo)); VALGRIND_MAKE_MEM_NOACCESS(p->size, sizeof(INTERNAL_SIZE_T)); VALGRIND_MAKE_MEM_NOACCESS(p->req, sizeof(INTERNAL_SIZE_T)); VALGRIND_MAKE_MEM_NOACCESS(p->bk, sizeof(struct chunkinfo*)); VALGRIND_MAKE_MEM_NOACCESS(p->chunk, sizeof(mchunkptr)); if (UNLIKELY(newciinfo->freecounter == NUMBER_FREE_CHUNKS)) freeciregion(newciinfo); break; } newciinfo = newciinfo->next; } while (newciinfo); } } } /* Calculate the hash table entry for a chunk */ #ifdef STARTHEAP_IS_ZERO #define hash(p) (((unsigned long) p) >> 7) #else #define hash(p) (((unsigned long) p - (unsigned long) startheap) >> 7) #endif static void hashtable_add (chunkinfoptr ci) { chunkinfoptr temp, next; unsigned long hashval; mchunkptr cic = chunk (ci); hashval = hash (cic); if (hashval < AMOUNTHASH) { temp = hashtable[hashval]; #ifdef DNMALLOC_DEBUG fprintf(stderr, "hashtable_add: %p, %lu\n", chunk(ci), hashval); #endif /* If no pointer to a chunk info list is stored at this location * in the hashtable or if the chunk's address is smaller than the * one present, add the chunk to the front of the linked list */ if (temp == 0 || chunk (temp) > cic) { ci->hash_next = temp; hashtable[hashval] = ci; if (!temp) /* more likely case */ goto out; temp->prev_size = chunksize(ci); return; } else { /* We must place the chunk in the linked list for this hashentry * Loop to end of list or to a position where temp's chunk's address * is larger than the new chunkinfo's chunk's address */ if (!temp->hash_next || (chunk (temp->hash_next) > cic)) { ci->hash_next = temp->hash_next; temp->hash_next = ci; } else { while ((temp->hash_next != 0) && (chunk (temp->hash_next) < cic)) { temp = temp->hash_next; } /* Place in linked list if not already there */ if (!temp->hash_next || !(chunk (temp->hash_next) == cic)) { ci->hash_next = temp->hash_next; temp->hash_next = ci; } } } } else { #ifdef DNMALLOC_CHECKS if (hashval >= AMOUNTHASH) { fprintf(stderr, "Dnmalloc error: trying to write outside of the bounds of the hashtable, this is definitely a bug, please email dnmalloc@fort-knox.org (hashval: %lu, AMOUNTHASH: %lu, HEAPMAXSIZE_HALF %lu PGSIZE %ld CHUNKINFOPAGE %ld chunk: %p, chunkinfo: %p, startheap: %p).\n", hashval, AMOUNTHASH, HEAPMAXSIZE_HALF, PGSIZE, CHUNKINFOPAGE, chunk(ci), ci, startheap); abort(); } #else assert(hashval < AMOUNTHASH); #endif } out: next = next_chunkinfo(ci); if (!next) return; next->prev_size = chunksize(ci); } static void hashtable_insert (chunkinfoptr ci_orig, chunkinfoptr ci_insert) { chunkinfoptr next; #ifdef DNMALLOC_DEBUG fprintf(stderr, "hashtable_ins: %p, %lu\n", chunk(ci_insert), (unsigned long)hash(chunk(ci_insert)); #endif if (hash(chunk(ci_orig)) != hash(chunk(ci_insert))) { hashtable_add(ci_insert); } else { ci_insert->hash_next = ci_orig->hash_next; ci_orig->hash_next = ci_insert; /* added for prevsize */ if (!(ci_insert->hash_next)) next = next_chunkinfo(ci_insert); else next = ci_insert->hash_next; if (!next) { ci_insert->prev_size = chunksize(ci_orig); } else { next->prev_size = chunksize(ci_insert); ci_insert->prev_size = chunksize(ci_orig); } } } static void hashtable_remove (mchunkptr p) { chunkinfoptr prevtemp, temp; unsigned long hashval; hashval = hash (p); #ifdef DNMALLOC_DEBUG fprintf(stderr, "hashtable_rem: %p, %lu\n", p, hashval); #endif assert(hashval < AMOUNTHASH); /* rw */ prevtemp = temp = hashtable[hashval]; if (chunk (temp) == p) { hashtable[hashval] = temp->hash_next; } else { if (temp && chunk (temp) != p) { do { prevtemp = temp; temp = temp->hash_next; } while (temp && chunk (temp) != p); } #ifdef DNMALLOC_CHECKS if (!temp) { fprintf (stderr, "Dnmalloc error (hash_rm): could not find a chunkinfo for the chunk %p in the hashtable at entry %lu\n This is definitely a bug, please report it to dnmalloc@fort-knox.org.\n", p, hashval); abort(); } #else assert(temp != NULL); #endif if (temp) prevtemp->hash_next = temp->hash_next; } } /* mmapped chunks are multiples of pagesize, no hash_nexts, * just remove from the hashtable */ #define hashtable_remove_mmapped(p) hashtable[hash(p)] = 0; static void hashtable_skiprm (chunkinfoptr ci_orig, chunkinfoptr ci_todelete) { unsigned long hashval; chunkinfoptr next; #ifdef DNMALLOC_DEBUG fprintf(stderr, "hashtable_skiprm: %p, %lu\n", chunk(ci_todelete), hash(chunk(ci_todelete))); #endif if (ci_orig->hash_next != ci_todelete) { hashval = hash(chunk(ci_todelete)); assert(hashval < AMOUNTHASH); /* rw */ #ifdef DNMALLOC_CHECKS if (hashtable[hashval] != ci_todelete ) { fprintf(stderr, "Dnmalloc error: trying to delete wrong value (hash: %lu): ci_todelete: %p (%p), hashtable[hashval]: %p (%p)\n This is definitely a bug, please report it to dnmalloc@fort-knox.org.\n", hashval, ci_todelete, chunk(ci_todelete), hashtable[hashval], chunk(hashtable[hashval])); } #else assert(hashtable[hashval] == ci_todelete); #endif hashtable[hashval] = ci_todelete->hash_next; } else { ci_orig->hash_next = ci_todelete->hash_next; if (!ci_orig->hash_next) { next = next_chunkinfo(ci_orig); } else { next = ci_orig->hash_next; } if (next) next->prev_size = chunksize(ci_orig); } } static chunkinfoptr hashtable_lookup (mchunkptr p) { chunkinfoptr ci; unsigned long hashval; /* if we were called wrongly * if ((char *) p < startheap) return 0; */ if ((char *) p >= startheap) { hashval = hash (p); assert(hashval < AMOUNTHASH); /* rw */ ci = hashtable[hashval]; if (ci && chunk (ci) == p) return ci; if (ci) { do { ci = ci->hash_next; } while (ci && chunk (ci) != p); } #ifdef DNMALLOC_CHECKS /* This should never occur but if it does, we'd like to know */ if (!ci) { fprintf (stderr, "Dnmalloc error: could not find a chunkinfo for the chunk %p in the hashtable at entry %lu\n This is definitely a bug, please report it to dnmalloc@fort-knox.org.\n", p, hashval); abort(); } #else assert(ci != NULL); #endif return ci; } return 0; } /* ----------- Internal state representation and initialization ----------- */ struct malloc_state { /* The maximum chunk size to be eligible for fastbin */ INTERNAL_SIZE_T max_fast; /* low 2 bits used as flags */ /* Fastbins */ mfastbinptr fastbins[NFASTBINS]; /* Base of the topmost chunk -- not otherwise kept in a bin */ chunkinfoptr top; /* The remainder from the most recent split of a small request */ chunkinfoptr last_remainder; /* Normal bins */ struct chunkinfo bins[NBINS]; /* Bitmap of bins. Trailing zero map handles cases of largest binned size */ unsigned int binmap[BINMAPSIZE+1]; /* Tunable parameters */ CHUNK_SIZE_T trim_threshold; INTERNAL_SIZE_T top_pad; INTERNAL_SIZE_T mmap_threshold; /* Memory map support */ int n_mmaps; int n_mmaps_max; int max_n_mmaps; /* Cache malloc_getpagesize */ unsigned int pagesize; /* Canary */ char guard_stored[GUARD_SIZE]; /* Track properties of MORECORE */ unsigned int morecore_properties; /* Statistics */ INTERNAL_SIZE_T mmapped_mem; INTERNAL_SIZE_T sbrked_mem; INTERNAL_SIZE_T max_sbrked_mem; INTERNAL_SIZE_T max_mmapped_mem; INTERNAL_SIZE_T max_total_mem; }; typedef struct malloc_state *mstate; /* There is exactly one instance of this struct in this malloc. If you are adapting this malloc in a way that does NOT use a static malloc_state, you MUST explicitly zero-fill it before using. This malloc relies on the property that malloc_state is initialized to all zeroes (as is true of C statics). */ static struct malloc_state * av_ = NULL; /* never directly referenced */ /* All uses of av_ are via get_malloc_state(). At most one "call" to get_malloc_state is made per invocation of the public versions of malloc and free, but other routines that in turn invoke malloc and/or free may call more then once. Also, it is called in check* routines if DEBUG is set. */ #define get_malloc_state() (av_) /* Initialize a malloc_state struct. This is called only from within malloc_consolidate, which needs be called in the same contexts anyway. It is never called directly outside of malloc_consolidate because some optimizing compilers try to inline it at all call points, which turns out not to be an optimization at all. (Inlining it in malloc_consolidate is fine though.) */ #if __STD_C static void malloc_mmap_state(void) #else static void malloc_mmap_state() #endif { int mprot; unsigned long pagesize = malloc_getpagesize; size_t size = (sizeof(struct malloc_state) + pagesize - 1) & ~(pagesize - 1); void * foo = MMAP(0, size+(2*pagesize), PROT_READ|PROT_WRITE, MAP_PRIVATE); #ifdef NDEBUG if (foo == MAP_FAILED) { fprintf (stderr, "Couldn't mmap struct malloc_state: %s\n", strerror (errno)); abort (); } #else assert(foo != MAP_FAILED); #endif mprot = mprotect(foo, pagesize, PROT_NONE); #ifdef NDEBUG if (mprot == -1) { fprintf (stderr, "Couldn't mprotect first non-rw page for struct malloc_state: %s\n", strerror (errno)); abort (); } #else assert(mprot != -1); #endif av_ = (struct malloc_state *) ((char*)foo + pagesize); MALLOC_ZERO(av_, sizeof(struct malloc_state)); mprot = mprotect((void*)((char*)foo + size + pagesize), (size_t) pagesize, PROT_NONE); #ifdef NDEBUG if (mprot == -1) { fprintf (stderr, "Couldn't mprotect last non-rw page for struct malloc_state: %s\n", strerror (errno)); abort (); } #else assert(mprot != -1); #endif } #if __STD_C static void malloc_init_state(mstate av) #else static void malloc_init_state(av) mstate av; #endif { int i; mbinptr bin; void * morecore_test = MORECORE(0); unsigned long hashval; /* Test morecore function */ set_morecore32bit(av); if (morecore_test == MORECORE_FAILURE) { set_nonmorecore32bit(av); } else { /* On 64bit systems, the heap may be located above the * 32bit address space. Since mmap() probably still can be * convinced to map within 32bit, we don't use sbrk(). */ hashval = hash (morecore_test); if (hashval >= AMOUNTHASH) { set_nonmorecore32bit(av); } } /* Establish circular links for normal bins */ for (i = 1; i < NBINS; ++i) { bin = bin_at(av,i); bin->fd = bin->bk = bin; } av->top_pad = DEFAULT_TOP_PAD; av->n_mmaps_max = DEFAULT_MMAP_MAX; av->mmap_threshold = DEFAULT_MMAP_THRESHOLD; av->trim_threshold = DEFAULT_TRIM_THRESHOLD; #if MORECORE_CONTIGUOUS set_contiguous(av); #else set_noncontiguous(av); #endif set_max_fast(av, DEFAULT_MXFAST); av->top = cireg_getfree (); av->top->chunk = (mchunkptr) startheap; av->top->size = 0; set_previnuse(av->top); clear_inuse(av->top); hashtable[0] = av->top; av->pagesize = malloc_getpagesize; memcpy(av->guard_stored, dnmalloc_arc4random(), GUARD_SIZE); } /* Other internal utilities operating on mstates */ #if __STD_C static Void_t* sYSMALLOc(INTERNAL_SIZE_T, mstate); static int sYSTRIm(size_t, mstate); static void malloc_consolidate(mstate); #else static Void_t* sYSMALLOc(); static int sYSTRIm(); static void malloc_consolidate(); #endif /* dnmalloc functions */ /* needs mstate so moved here */ static chunkinfoptr next_chunkinfo (chunkinfoptr ci) { mchunkptr nextp; unsigned long hashval; chunkinfoptr cinfonextp; mstate av = get_malloc_state(); /* ci is not the last element in the linked list, just return the next chunkinfo from the list */ if (!ci->hash_next) { /* ci is the last element, find the next chunkinfo by * looking up the chunkinfo for the chunk that is after p's chunk */ nextp = (mchunkptr) (((char *) (ci->chunk)) + chunksize (ci)); if (!(nextp == av->top->chunk)) { hashval = hash (nextp); /* assert(hashval < AMOUNTHASH); *//* major bottleneck */ cinfonextp = hashtable[hashval]; if (cinfonextp && chunk (cinfonextp) == nextp) return cinfonextp; #ifdef DNMALLOC_CHECKS_EXTRA /* This seems bogus; a chunkinfo may legally have no nextp if * it's the last one allocated (?) */ else { if (cinfonextp) fprintf (stderr, "Dnmalloc error: could not find a next chunkinfo for the chunk %p in the hashtable at entry %lu, cinfonextp: %p, chunk(cinfonextp): %p, nextp: %p\n This is definitely a bug, please report it to dnmalloc@fort-knox.org.\n", chunk(ci), hashval, cinfonextp, chunk(cinfonextp), nextp); else fprintf (stderr, "Dnmalloc error: could not find a next chunkinfo for the chunk %p in the hashtable at entry %lu, cinfonextp: %s, chunk(cinfonextp): %s, nextp: %p\n This is definitely a bug, please report it to dnmalloc@fort-knox.org.\n", chunk(ci), hashval, "null", "null", nextp); } #endif return NULL; } else { return av->top; } } else { return (ci->hash_next); } } static int is_next_chunk(chunkinfoptr oldp, chunkinfoptr newp) { mchunkptr nextp; if (oldp->hash_next == newp) return 1; nextp = (mchunkptr) (((char *) (oldp->chunk)) + chunksize (oldp)); if (nextp == chunk(newp)) return 1; return 0; } /* Get the chunkinfo of the physically previous chunk */ /* Since we disposed of prev_size, we need this function to find the previous */ static chunkinfoptr prev_chunkinfo (chunkinfoptr ci) { unsigned int i; chunkinfoptr prev; mchunkptr prevchunk = 0; /* chunkinfoptr temp; */ /* Get the hashtable location of the chunkinfo */ i = hash (chunk (ci)); assert(i < AMOUNTHASH); /* rw */ /* Get the first element of the linked list of chunkinfo's that contains p */ prev = hashtable[i]; if (ci == prev) { prevchunk = (mchunkptr) (((char *) (ci->chunk)) - (ci->prev_size)); i = hash(prevchunk); assert(i < AMOUNTHASH); /* rw */ /* Loop over the linked list until we reach the last element */ for (prev = hashtable[i]; prev->hash_next != 0; prev = prev->hash_next) ; } else { /* p is not the first element in the linked list, we can just loop over the list and return the previous */ for (prev = hashtable[i]; prev->hash_next != ci; prev = prev->hash_next); } return prev; } /* Debugging support Dnmalloc broke dlmallocs debugging functions, should fix them some time in the future, for now leave them undefined. */ #define check_chunk(P) #define check_free_chunk(P) #define check_inuse_chunk(P) #define check_remalloced_chunk(P,N) #define check_malloced_chunk(P,N) #define check_malloc_state() /* ----------- Routines dealing with system allocation -------------- */ /* sysmalloc handles malloc cases requiring more memory from the system. On entry, it is assumed that av->top does not have enough space to service request for nb bytes, thus requiring that av->top be extended or replaced. */ #if __STD_C static Void_t* sYSMALLOc(INTERNAL_SIZE_T nb, mstate av) #else static Void_t* sYSMALLOc(nb, av) INTERNAL_SIZE_T nb; mstate av; #endif { chunkinfoptr old_top; /* incoming value of av->top */ INTERNAL_SIZE_T old_size; /* its size */ char* old_end; /* its end address */ long size; /* arg to first MORECORE or mmap call */ char* brk; /* return value from MORECORE */ long correction; /* arg to 2nd MORECORE call */ char* snd_brk; /* 2nd return val */ INTERNAL_SIZE_T front_misalign; /* unusable bytes at front of new space */ INTERNAL_SIZE_T end_misalign; /* partial page left at end of new space */ char* aligned_brk; /* aligned offset into brk */ chunkinfoptr p; /* the allocated/returned chunk */ chunkinfoptr remainder; /* remainder from allocation */ chunkinfoptr fencepost; /* fencepost */ CHUNK_SIZE_T remainder_size; /* its size */ CHUNK_SIZE_T sum; /* for updating stats */ size_t pagemask = av->pagesize - 1; #ifdef DNMALLOC_DEBUG fprintf(stderr, "Enter sysmalloc\n"); #endif /* If there is space available in fastbins, consolidate and retry malloc from scratch rather than getting memory from system. This can occur only if nb is in smallbin range so we didn't consolidate upon entry to malloc. It is much easier to handle this case here than in malloc proper. */ if (have_fastchunks(av)) { Void_t * retval; assert(in_smallbin_range(nb)); malloc_consolidate(av); #ifdef DNMALLOC_DEBUG fprintf(stderr, "Return sysmalloc have_fastchunks\n"); #endif retval = mALLOc(nb - MALLOC_ALIGN_MASK); VALGRIND_FREELIKE_BLOCK(retval, 0); return retval; } /* If have mmap, and the request size meets the mmap threshold, and the system supports mmap, and there are few enough currently allocated mmapped regions, try to directly map this request rather than expanding top. */ if (UNLIKELY((CHUNK_SIZE_T)(nb) >= (CHUNK_SIZE_T)(av->mmap_threshold) && (av->n_mmaps < av->n_mmaps_max))) { char* mm; /* return value from mmap call*/ /* Round up size to nearest page. For mmapped chunks, the overhead is one SIZE_SZ unit larger than for normal chunks, because there is no following chunk whose prev_size field could be used. */ size = (nb + MALLOC_ALIGN_MASK + pagemask) & ~pagemask; /* Don't try if size wraps around 0 */ if ((CHUNK_SIZE_T)(size) > (CHUNK_SIZE_T)(nb)) { mm = (char*)(MMAP(0, size, PROT_READ|PROT_WRITE, MAP_PRIVATE)); if (mm != (char*)(MORECORE_FAILURE)) { VALGRIND_MAKE_MEM_NOACCESS(mm,size); /* The offset to the start of the mmapped region is stored in the prev_size field of the chunk. This allows us to adjust returned start address to meet alignment requirements here and in memalign(), and still be able to compute proper address argument for later munmap in free() and realloc(). */ front_misalign = (INTERNAL_SIZE_T) mm & MALLOC_ALIGN_MASK; p = cireg_getfree(); if (front_misalign > 0) { correction = MALLOC_ALIGNMENT - front_misalign; p->chunk = (mchunkptr)(mm + correction); p->hash_next = (chunkinfoptr) correction; set_head(p, (size - correction) |INUSE|IS_MMAPPED); } else { p->chunk = (mchunkptr)mm; p->hash_next = 0; set_head(p, size|INUSE|IS_MMAPPED); } hashtable_add(p); /* update statistics */ if (++av->n_mmaps > av->max_n_mmaps) av->max_n_mmaps = av->n_mmaps; sum = av->mmapped_mem += size; if (sum > (CHUNK_SIZE_T)(av->max_mmapped_mem)) av->max_mmapped_mem = sum; sum += av->sbrked_mem; if (sum > (CHUNK_SIZE_T)(av->max_total_mem)) av->max_total_mem = sum; check_chunk(p); #ifdef DNMALLOC_DEBUG fprintf(stderr, "Return mmapped (%lu, total %lu)\n", size, (unsigned long)/* size_t */av->max_total_mem ); #endif return chunk(p); } } } /* Record incoming configuration of top */ old_top = av->top; old_size = chunksize(old_top); old_end = (char*)(chunk_at_offset(chunk(old_top), old_size)); brk = snd_brk = (char*)(MORECORE_FAILURE); /* If not the first time through, we require old_size to be at least MINSIZE and to have prev_inuse set. */ /* assert((old_top == initial_top(av) && old_size == 0) || ((CHUNK_SIZE_T) (old_size) >= MINSIZE && prev_inuse(old_top))); */ /* Precondition: not enough current space to satisfy nb request */ assert((CHUNK_SIZE_T)(old_size) < (CHUNK_SIZE_T)(nb + MINSIZE)); /* Precondition: all fastbins are consolidated */ assert(!have_fastchunks(av)); /* Request enough space for nb + pad + overhead */ size = nb + av->top_pad + MINSIZE; /* If contiguous, we can subtract out existing space that we hope to combine with new space. We add it back later only if we don't actually get contiguous space. */ if (contiguous(av)) size -= old_size; /* Round to a multiple of page size. If MORECORE is not contiguous, this ensures that we only call it with whole-page arguments. And if MORECORE is contiguous and this is not first time through, this preserves page-alignment of previous calls. Otherwise, we correct to page-align below. */ size = (size + pagemask) & ~pagemask; /* Don't try to call MORECORE if argument is so big as to appear negative. Note that since mmap takes size_t arg, it may succeed below even if we cannot call MORECORE. */ if (size > 0 && morecore32bit(av)) brk = (char*)(MORECORE(size)); /* If have mmap, try using it as a backup when MORECORE fails or cannot be used. This is worth doing on systems that have "holes" in address space, so sbrk cannot extend to give contiguous space, but space is available elsewhere. Note that we ignore mmap max count and threshold limits, since the space will not be used as a segregated mmap region. */ if (brk != (char*)(MORECORE_FAILURE)) { av->sbrked_mem += size; VALGRIND_MAKE_MEM_NOACCESS(brk,size); } else { #ifdef DNMALLOC_DEBUG fprintf(stderr, "Morecore failure in sysmalloc\n"); #endif /* Cannot merge with old top, so add its size back in */ if (contiguous(av)) size = (size + old_size + pagemask) & ~pagemask; /* If we are relying on mmap as backup, then use larger units */ if ((CHUNK_SIZE_T)(size) < (CHUNK_SIZE_T)(MMAP_AS_MORECORE_SIZE)) size = MMAP_AS_MORECORE_SIZE; /* Don't try if size wraps around 0 */ if ((CHUNK_SIZE_T)(size) > (CHUNK_SIZE_T)(nb)) { #ifdef DNMALLOC_DEBUG fprintf(stderr, "Try mmap in sysmalloc\n"); #endif brk = (char*)(MMAP(0, size, PROT_READ|PROT_WRITE, MAP_PRIVATE)); if (brk != (char*)(MORECORE_FAILURE)) { VALGRIND_MAKE_MEM_NOACCESS(brk,size); av->mmapped_mem += size; #ifdef DNMALLOC_DEBUG fprintf(stderr, "Mmapped successfully in sysmalloc %p\n", brk); #endif /* We do not need, and cannot use, another sbrk call to find end */ snd_brk = brk + size; /* Record that we no longer have a contiguous sbrk region. After the first time mmap is used as backup, we do not ever rely on contiguous space since this could incorrectly bridge regions. */ set_noncontiguous(av); } } } if (brk != (char*)(MORECORE_FAILURE)) { #ifdef DNMALLOC_DEBUG fprintf(stderr, "Success path %lu allocated, sbrked %lu\n", size, (unsigned long)av->sbrked_mem); #endif /* av->sbrked_mem += size; moved up */ /* If MORECORE extends previous space, we can likewise extend top size. */ if (brk == old_end && snd_brk == (char*)(MORECORE_FAILURE)) { set_head(old_top, (size + old_size) | PREV_INUSE); #ifdef DNMALLOC_DEBUG fprintf(stderr, "Previous space extended\n"); #endif } /* Otherwise, make adjustments: * If the first time through or noncontiguous, we need to call sbrk just to find out where the end of memory lies. * We need to ensure that all returned chunks from malloc will meet MALLOC_ALIGNMENT * If there was an intervening foreign sbrk, we need to adjust sbrk request size to account for fact that we will not be able to combine new space with existing space in old_top. * Almost all systems internally allocate whole pages at a time, in which case we might as well use the whole last page of request. So we allocate enough more memory to hit a page boundary now, which in turn causes future contiguous calls to page-align. */ else { /* front_misalign = 0; *//*superfluous */ /* end_misalign = 0; *//*superfluous */ correction = 0; aligned_brk = brk; /* If MORECORE returns an address lower than we have seen before, we know it isn't really contiguous. This and some subsequent checks help cope with non-conforming MORECORE functions and the presence of "foreign" calls to MORECORE from outside of malloc or by other threads. We cannot guarantee to detect these in all cases, but cope with the ones we do detect. */ if (contiguous(av) && old_size != 0 && brk < old_end) { set_noncontiguous(av); } /* handle contiguous cases */ if (contiguous(av)) { #ifdef DNMALLOC_DEBUG fprintf(stderr, "Handle contiguous cases\n"); #endif /* We can tolerate forward non-contiguities here (usually due to foreign calls) but treat them as part of our space for stats reporting. */ if (old_size != 0) av->sbrked_mem += brk - old_end; /* Guarantee alignment of first new chunk made from this space */ front_misalign = (INTERNAL_SIZE_T) brk & MALLOC_ALIGN_MASK; if (front_misalign > 0) { /* Skip over some bytes to arrive at an aligned position. We don't need to specially mark these wasted front bytes. They will never be accessed anyway because prev_inuse of av->top (and any chunk created from its start) is always true after initialization. */ correction = MALLOC_ALIGNMENT - front_misalign; aligned_brk += correction; } /* If this isn't adjacent to existing space, then we will not be able to merge with old_top space, so must add to 2nd request. */ correction += old_size; /* Extend the end address to hit a page boundary */ end_misalign = (INTERNAL_SIZE_T)(brk + size + correction); correction += ((end_misalign + pagemask) & ~pagemask) - end_misalign; assert(correction >= 0); snd_brk = (char*)(MORECORE(correction)); if (snd_brk == (char*)(MORECORE_FAILURE)) { /* If can't allocate correction, try to at least find out current brk. It might be enough to proceed without failing. */ correction = 0; snd_brk = (char*)(MORECORE(0)); } else if (snd_brk < brk) { /* If the second call gives noncontiguous space even though it says it won't, the only course of action is to ignore results of second call, and conservatively estimate where the first call left us. Also set noncontiguous, so this won't happen again, leaving at most one hole. Note that this check is intrinsically incomplete. Because MORECORE is allowed to give more space than we ask for, there is no reliable way to detect a noncontiguity producing a forward gap for the second call. */ snd_brk = brk + size; correction = 0; set_noncontiguous(av); } else { VALGRIND_MAKE_MEM_NOACCESS(snd_brk,correction); } } /* handle non-contiguous cases */ else { #ifdef DNMALLOC_DEBUG fprintf(stderr, "Handle non-contiguous cases\n"); #endif /* MORECORE/mmap must correctly align */ assert(aligned_OK(brk)); /* Find out current end of memory */ if (snd_brk == (char*)(MORECORE_FAILURE)) { snd_brk = (char*)(MORECORE(0)); av->sbrked_mem += snd_brk - brk - size; } #ifdef DNMALLOC_DEBUG fprintf(stderr, "Sbrked now %lu\n", (unsigned long)av->sbrked_mem); #endif } /* Adjust top based on results of second sbrk. * * If mmap() has been used as backup for failed morecore(), * we end up in this branch as well. */ if (snd_brk != (char*)(MORECORE_FAILURE)) { #ifdef DNMALLOC_DEBUG fprintf(stderr, "Adjust top, correction %lu\n", correction); #endif /* hashtable_remove(chunk(av->top)); *//* rw 19.05.2008 removed */ av->top = cireg_getfree(); av->top->chunk = (mchunkptr)aligned_brk; set_head(av->top, (snd_brk - aligned_brk + correction) | PREV_INUSE); #ifdef DNMALLOC_DEBUG fprintf(stderr, "Adjust top, top %p size %lu\n", av->top, (unsigned long)chunksize(av->top)); #endif hashtable_add(av->top); av->sbrked_mem += correction; /* If not the first time through, we either have a gap due to foreign sbrk or a non-contiguous region. Insert a double fencepost at old_top to prevent consolidation with space we don't own. These fenceposts are artificial chunks that are marked as inuse. Original dlmalloc had two of these but too small to use. To ensure that the linked lists contain a maximum of 8 elements we only use 1. Inuse is determined by the current rather than the next chunk anyway. */ if (old_size != 0) { #ifdef DNMALLOC_DEBUG fprintf(stderr, "Shrink old_top to insert fenceposts\n"); #endif /* Shrink old_top to insert fenceposts, keeping size a multiple of MALLOC_ALIGNMENT. We know there is at least enough space in old_top to do this. */ #ifdef DNMALLOC_DEBUG fprintf(stderr, "Adjust top, old_top %p old_size before %lu\n", old_top, (unsigned long)old_size); #endif old_size = (old_size - 4*SIZE_SZ) & ~MALLOC_ALIGN_MASK; set_head(old_top, old_size | PREV_INUSE); #ifdef DNMALLOC_DEBUG fprintf(stderr, "Adjust top, old_size after %lu\n", (unsigned long)old_size); #endif /* Note that the following assignments completely overwrite old_top when old_size was previously MINSIZE. This is intentional. We need the fencepost, even if old_top otherwise gets lost. */ /* dnmalloc, we need the fencepost to be 16 bytes, however since it's marked inuse it will never be coalesced */ fencepost = cireg_getfree(); fencepost->chunk = (mchunkptr) chunk_at_offset(chunk(old_top), old_size); fencepost->size = 16|INUSE|PREV_INUSE; hashtable_add(fencepost); /* If possible, release the rest, suppressing trimming. */ if (old_size >= MINSIZE) { INTERNAL_SIZE_T tt = av->trim_threshold; #ifdef DNMALLOC_DEBUG fprintf(stderr, "Release\n"); #endif av->trim_threshold = (INTERNAL_SIZE_T)(-1); set_head(old_top, old_size | PREV_INUSE | INUSE); guard_set(av->guard_stored, old_top, 0, old_size); VALGRIND_MALLOCLIKE_BLOCK(chunk(old_top), old_size, 0, 0); fREe(chunk(old_top)); av->trim_threshold = tt; #ifdef DNMALLOC_DEBUG fprintf(stderr, "Release done\n"); #endif } #ifdef DNMALLOC_DEBUG fprintf(stderr, "Adjust top, size %lu\n", (unsigned long)chunksize(av->top)); #endif } /* fenceposts */ } /* adjust top */ } /* not extended previous region */ /* Update statistics */ sum = av->sbrked_mem; if (sum > (CHUNK_SIZE_T)(av->max_sbrked_mem)) av->max_sbrked_mem = sum; sum += av->mmapped_mem; if (sum > (CHUNK_SIZE_T)(av->max_total_mem)) av->max_total_mem = sum; check_malloc_state(); /* finally, do the allocation */ p = av->top; size = chunksize(p); #ifdef DNMALLOC_DEBUG fprintf(stderr, "Size: %lu nb+MINSIZE: %lu\n", (CHUNK_SIZE_T)(size), (CHUNK_SIZE_T)(nb + MINSIZE)); #endif /* check that one of the above allocation paths succeeded */ if ((CHUNK_SIZE_T)(size) >= (CHUNK_SIZE_T)(nb + MINSIZE)) { remainder_size = size - nb; remainder = cireg_getfree(); remainder->chunk = chunk_at_offset(chunk(p), nb); av->top = remainder; set_head(p, nb | PREV_INUSE | INUSE); set_head(remainder, remainder_size | PREV_INUSE); hashtable_insert (p, av->top); check_malloced_chunk(p, nb); #ifdef DNMALLOC_DEBUG fprintf(stderr, "Return any (total %lu)\n", (unsigned long)/* size_t */av->max_total_mem ); #endif return chunk(p); } } #ifdef DNMALLOC_DEBUG fprintf(stderr, "Return failed (total %lu)\n", (unsigned long)/* size_t */av->max_total_mem ); #endif /* catch all failure paths */ MALLOC_FAILURE_ACTION; return 0; } /* sYSTRIm is an inverse of sorts to sYSMALLOc. It gives memory back to the system (via negative arguments to sbrk) if there is unused memory at the `high' end of the malloc pool. It is called automatically by free() when top space exceeds the trim threshold. It is also called by the public malloc_trim routine. It returns 1 if it actually released any memory, else 0. */ #if __STD_C static int sYSTRIm(size_t pad, mstate av) #else static int sYSTRIm(pad, av) size_t pad; mstate av; #endif { long top_size; /* Amount of top-most memory */ long extra; /* Amount to release */ long released; /* Amount actually released */ char* current_brk; /* address returned by pre-check sbrk call */ char* new_brk; /* address returned by post-check sbrk call */ size_t pagesz; pagesz = av->pagesize; top_size = chunksize(av->top); /* Release in pagesize units, keeping at least one page */ extra = ((top_size - pad - MINSIZE + (pagesz-1)) / pagesz - 1) * pagesz; if (extra > 0) { /* Only proceed if end of memory is where we last set it. This avoids problems if there were foreign sbrk calls. */ current_brk = (char*)(MORECORE(0)); if (current_brk == (char*)(av->top) + top_size) { /* Attempt to release memory. We ignore MORECORE return value, and instead call again to find out where new end of memory is. This avoids problems if first call releases less than we asked, of if failure somehow altered brk value. (We could still encounter problems if it altered brk in some very bad way, but the only thing we can do is adjust anyway, which will cause some downstream failure.) */ MORECORE(-extra); new_brk = (char*)(MORECORE(0)); if (new_brk != (char*)MORECORE_FAILURE) { released = (long)(current_brk - new_brk); if (released != 0) { /* Success. Adjust top. */ av->sbrked_mem -= released; set_head(av->top, (top_size - released) | PREV_INUSE); check_malloc_state(); return 1; } } } } return 0; } /* ------------------------------ malloc ------------------------------ */ #if __STD_C DL_STATIC Void_t* mALLOc(size_t bytes) #else DL_STATIC Void_t* mALLOc(bytes) size_t bytes; #endif { mstate av = get_malloc_state(); INTERNAL_SIZE_T nb; /* normalized request size */ unsigned int idx; /* associated bin index */ mbinptr bin; /* associated bin */ mfastbinptr* fb; /* associated fastbin */ chunkinfoptr victim; /* inspected/selected chunk */ INTERNAL_SIZE_T size; /* its size */ int victim_index; /* its bin index */ chunkinfoptr remainder; /* remainder from a split */ CHUNK_SIZE_T remainder_size; /* its size */ unsigned int block; /* bit map traverser */ unsigned int bit; /* bit map traverser */ unsigned int map; /* current word of binmap */ chunkinfoptr fwd; /* misc temp for linking */ chunkinfoptr bck; /* misc temp for linking */ Void_t* retval; /* chunkinfoptr next; */ /* Convert request size to internal form by adding SIZE_SZ bytes overhead plus possibly more to obtain necessary alignment and/or to obtain a size of at least MINSIZE, the smallest allocatable size. Also, checked_request2size traps (returning 0) request sizes that are so large that they wrap around zero when padded and aligned. */ #if defined(SH_CUTEST) extern int malloc_count; ++malloc_count; #endif checked_request2size(bytes, nb); /* Bypass search if no frees yet */ if (av && have_anychunks(av)) { goto av_initialized; } else { if (!av || av->max_fast == 0) { /* initialization check */ malloc_consolidate(av); av = get_malloc_state(); } goto use_top; } av_initialized: /* If the size qualifies as a fastbin, first check corresponding bin. */ if ((CHUNK_SIZE_T)(nb) <= (CHUNK_SIZE_T)(av->max_fast)) { fb = &(av->fastbins[(fastbin_index(nb))]); if ( (victim = *fb) != 0) { *fb = victim->fd; check_remalloced_chunk(victim, nb); guard_set(av->guard_stored, victim, bytes, nb); VALGRIND_MALLOCLIKE_BLOCK(chunk(victim), bytes, 0, 0); return chunk(victim); } } /* If a small request, check regular bin. Since these "smallbins" hold one size each, no searching within bins is necessary. (For a large request, we need to wait until unsorted chunks are processed to find best fit. But for small ones, fits are exact anyway, so we can check now, which is faster.) */ if (in_smallbin_range(nb)) { idx = smallbin_index(nb); bin = bin_at(av,idx); if ((victim = last(bin)) != bin) { bck = victim->bk; bin->bk = bck; bck->fd = bin; set_all_inuse(victim); check_malloced_chunk(victim, nb); guard_set(av->guard_stored, victim, bytes, nb); VALGRIND_MALLOCLIKE_BLOCK(chunk(victim), bytes, 0, 0); return chunk(victim); } } /* If this is a large request, consolidate fastbins before continuing. While it might look excessive to kill all fastbins before even seeing if there is space available, this avoids fragmentation problems normally associated with fastbins. Also, in practice, programs tend to have runs of either small or large requests, but less often mixtures, so consolidation is not invoked all that often in most programs. And the programs that it is called frequently in otherwise tend to fragment. */ else { idx = largebin_index(nb); if (have_fastchunks(av)) malloc_consolidate(av); } /* Process recently freed or remaindered chunks, taking one only if it is exact fit, or, if this a small request, the chunk is remainder from the most recent non-exact fit. Place other traversed chunks in bins. Note that this step is the only place in any routine where chunks are placed in bins. */ while ( (victim = unsorted_chunks(av)->bk) != unsorted_chunks(av)) { bck = victim->bk; size = chunksize(victim); /* If a small request, try to use last remainder if it is the only chunk in unsorted bin. This helps promote locality for runs of consecutive small requests. This is the only exception to best-fit, and applies only when there is no exact fit for a small chunk. */ if (UNLIKELY(in_smallbin_range(nb) && bck == unsorted_chunks(av) && victim == av->last_remainder && (CHUNK_SIZE_T)(size) > (CHUNK_SIZE_T)(nb + MINSIZE))) { /* split and reattach remainder */ remainder_size = size - nb; remainder = cireg_getfree(); remainder->chunk = chunk_at_offset(chunk(victim), nb); unsorted_chunks(av)->bk = unsorted_chunks(av)->fd = remainder; av->last_remainder = remainder; remainder->bk = remainder->fd = unsorted_chunks(av); set_head(victim, nb | PREV_INUSE|INUSE); set_head(remainder, remainder_size | PREV_INUSE); hashtable_insert(victim, remainder); check_malloced_chunk(victim, nb); guard_set(av->guard_stored, victim, bytes, nb); VALGRIND_MALLOCLIKE_BLOCK(chunk(victim), bytes, 0, 0); return chunk(victim); } /* remove from unsorted list */ unsorted_chunks(av)->bk = bck; bck->fd = unsorted_chunks(av); /* Take now instead of binning if exact fit */ if (UNLIKELY(size == nb)) { set_all_inuse(victim) check_malloced_chunk(victim, nb); guard_set(av->guard_stored, victim, bytes, nb); VALGRIND_MALLOCLIKE_BLOCK(chunk(victim), bytes, 0, 0); return chunk(victim); } /* place chunk in bin */ if (in_smallbin_range(size)) { victim_index = smallbin_index(size); bck = bin_at(av, victim_index); fwd = bck->fd; } else { victim_index = largebin_index(size); bck = bin_at(av, victim_index); fwd = bck->fd; if (UNLIKELY(fwd != bck)) { /* if smaller than smallest, place first */ if ((CHUNK_SIZE_T)(size) < (CHUNK_SIZE_T)(bck->bk->size)) { fwd = bck; bck = bck->bk; } else if ((CHUNK_SIZE_T)(size) >= (CHUNK_SIZE_T)(FIRST_SORTED_BIN_SIZE)) { /* maintain large bins in sorted order */ size |= PREV_INUSE|INUSE; /* Or with inuse bits to speed comparisons */ while ((CHUNK_SIZE_T)(size) < (CHUNK_SIZE_T)(fwd->size)) fwd = fwd->fd; bck = fwd->bk; } } } mark_bin(av, victim_index); victim->bk = bck; victim->fd = fwd; fwd->bk = victim; bck->fd = victim; } /* If a large request, scan through the chunks of current bin to find one that fits. (This will be the smallest that fits unless FIRST_SORTED_BIN_SIZE has been changed from default.) This is the only step where an unbounded number of chunks might be scanned without doing anything useful with them. However the lists tend to be short. */ if (!in_smallbin_range(nb)) { bin = bin_at(av, idx); victim = last(bin); if (UNLIKELY(victim != bin)) { do { size = chunksize(victim); if ((CHUNK_SIZE_T)(size) >= (CHUNK_SIZE_T)(nb)) { remainder_size = size - nb; unlink(victim, bck, fwd); /* Split */ if (remainder_size >= MINSIZE) { remainder = cireg_getfree(); remainder->chunk = chunk_at_offset(chunk(victim), nb); unsorted_chunks(av)->bk = unsorted_chunks(av)->fd = remainder; remainder->bk = remainder->fd = unsorted_chunks(av); set_head(victim, nb | PREV_INUSE | INUSE); set_head(remainder, remainder_size | PREV_INUSE); hashtable_insert(victim, remainder); check_malloced_chunk(victim, nb); guard_set(av->guard_stored, victim, bytes, nb); VALGRIND_MALLOCLIKE_BLOCK(chunk(victim), bytes, 0, 0); return chunk(victim); } /* Exhaust */ else { set_all_inuse(victim); check_malloced_chunk(victim, nb); guard_set(av->guard_stored, victim, bytes, nb); VALGRIND_MALLOCLIKE_BLOCK(chunk(victim), bytes, 0, 0); return chunk(victim); } } victim = victim->bk; } while(victim != bin); } } /* Search for a chunk by scanning bins, starting with next largest bin. This search is strictly by best-fit; i.e., the smallest (with ties going to approximately the least recently used) chunk that fits is selected. The bitmap avoids needing to check that most blocks are nonempty. */ ++idx; bin = bin_at(av,idx); block = idx2block(idx); map = av->binmap[block]; bit = idx2bit(idx); for (;;) { /* Skip rest of block if there are no more set bits in this block. */ if (bit > map || bit == 0) { do { if (++block >= BINMAPSIZE) /* out of bins */ goto use_top; } while ( (map = av->binmap[block]) == 0); bin = bin_at(av, (block << BINMAPSHIFT)); bit = 1; } /* Advance to bin with set bit. There must be one. */ while ((bit & map) == 0) { bin = next_bin(bin); bit <<= 1; assert(bit != 0); } /* Inspect the bin. It is likely to be non-empty */ victim = last(bin); /* If a false alarm (empty bin), clear the bit. */ if (victim == bin) { av->binmap[block] = map &= ~bit; /* Write through */ bin = next_bin(bin); bit <<= 1; } else { size = chunksize(victim); /* We know the first chunk in this bin is big enough to use. */ assert((CHUNK_SIZE_T)(size) >= (CHUNK_SIZE_T)(nb)); remainder_size = size - nb; /* unlink */ bck = victim->bk; bin->bk = bck; bck->fd = bin; /* Split */ if (remainder_size >= MINSIZE) { remainder = cireg_getfree(); remainder->chunk = chunk_at_offset(chunk(victim), nb); unsorted_chunks(av)->bk = unsorted_chunks(av)->fd = remainder; remainder->bk = remainder->fd = unsorted_chunks(av); /* advertise as last remainder */ if (in_smallbin_range(nb)) av->last_remainder = remainder; set_head(victim, nb | PREV_INUSE | INUSE); set_head(remainder, remainder_size | PREV_INUSE); hashtable_insert(victim, remainder); check_malloced_chunk(victim, nb); guard_set(av->guard_stored, victim, bytes, nb); VALGRIND_MALLOCLIKE_BLOCK(chunk(victim), bytes, 0, 0); return chunk(victim); } /* Exhaust */ else { set_all_inuse(victim); check_malloced_chunk(victim, nb); guard_set(av->guard_stored, victim, bytes, nb); VALGRIND_MALLOCLIKE_BLOCK(chunk(victim), bytes, 0, 0); return chunk(victim); } } } use_top: /* If large enough, split off the chunk bordering the end of memory (held in av->top). Note that this is in accord with the best-fit search rule. In effect, av->top is treated as larger (and thus less well fitting) than any other available chunk since it can be extended to be as large as necessary (up to system limitations). We require that av->top always exists (i.e., has size >= MINSIZE) after initialization, so if it would otherwise be exhuasted by current request, it is replenished. (The main reason for ensuring it exists is that we may need MINSIZE space to put in fenceposts in sysmalloc.) */ victim = av->top; size = chunksize(victim); if ((CHUNK_SIZE_T)(size) >= (CHUNK_SIZE_T)(nb + MINSIZE)) { remainder = cireg_getfree(); remainder_size = size - nb; remainder->chunk = chunk_at_offset(chunk(victim), nb); av->top = remainder; set_head(victim, nb | PREV_INUSE | INUSE); set_head(remainder, remainder_size | PREV_INUSE); hashtable_insert(victim, remainder); check_malloced_chunk(victim, nb); guard_set(av->guard_stored, victim, bytes, nb); VALGRIND_MALLOCLIKE_BLOCK(chunk(victim), bytes, 0, 0); return chunk(victim); } /* If no space in top, relay to handle system-dependent cases */ retval = sYSMALLOc(nb, av); if (retval) { #if PARANOIA > 2 victim = mem2chunk(retval); /* is used in guard_set macro */ #endif guard_set(av->guard_stored, victim, bytes, nb); } VALGRIND_MALLOCLIKE_BLOCK(retval, bytes, 0, 0); return retval; } /* ------------------------------ free ------------------------------ */ #if __STD_C DL_STATIC void fREe(Void_t* mem) #else DL_STATIC void fREe(mem) Void_t* mem; #endif { mstate av = get_malloc_state(); chunkinfoptr p; /* chunk corresponding to mem */ INTERNAL_SIZE_T size; /* its size */ mfastbinptr* fb; /* associated fastbin */ chunkinfoptr prevchunk; /* previous physical chunk */ chunkinfoptr nextchunk; /* next contiguous chunk */ INTERNAL_SIZE_T nextsize; /* its size */ INTERNAL_SIZE_T prevsize; /* size of previous contiguous chunk */ chunkinfoptr bck; /* misc temp for linking */ chunkinfoptr fwd; /* misc temp for linking */ chunkinfoptr next; #if defined(SH_CUTEST) extern int malloc_count; --malloc_count; #endif /* free(0) has no effect */ if (mem != 0) { p = hashtable_lookup(mem); /* check that memory is managed by us * and is inuse */ if (UNLIKELY(!p || !inuse(p))) { #ifdef DNMALLOC_CHECKS if (p) { fprintf(stderr, "Attempt to free memory not in use\n"); abort(); } else { fprintf(stderr, "Attempt to free memory not allocated\n"); abort(); } #endif assert(p && inuse(p)); return; } VALGRIND_FREELIKE_BLOCK(mem, 0); guard_check(av->guard_stored, p); size = chunksize(p); check_inuse_chunk(p); /* If eligible, place chunk on a fastbin so it can be found and used quickly in malloc. */ if ((CHUNK_SIZE_T)(size) <= (CHUNK_SIZE_T)(av->max_fast) #if TRIM_FASTBINS /* If TRIM_FASTBINS set, don't place chunks bordering top into fastbins */ && (chunk_at_offset(chunk(p), size) != av->top) #endif ) { set_fastchunks(av); fb = &(av->fastbins[fastbin_index(size)]); p->fd = *fb; *fb = p; } /* Consolidate other non-mmapped chunks as they arrive. */ else if (!chunk_is_mmapped(p)) { set_anychunks(av); nextchunk = next_chunkinfo(p); if (nextchunk) nextsize = chunksize(nextchunk); else nextsize = 0;/* gcc doesn't notice that it's only used if (nextchunk)*/ /* consolidate backward */ if (UNLIKELY(!prev_inuse(p))) { prevchunk = prev_chunkinfo(p); prevsize = chunksize(prevchunk); #ifdef DNMALLOC_CHECKS if (inuse(prevchunk)) { fprintf(stderr, "Dnmalloc error: trying to unlink an inuse chunk: %p (chunk: %p)\n This is definitely a bug, please report it to dnmalloc@fort-knox.org.\n", prevchunk, chunk(prevchunk)); abort(); } #else assert(!inuse(prevchunk)); #endif size += prevsize; unlink(prevchunk, bck, fwd); set_head(p, size | PREV_INUSE); hashtable_skiprm(prevchunk,p); /* This chunk no longer exists in any form: release the chunkinfoptr */ freecilst_add(p); p = prevchunk; } if (nextchunk) { if (nextchunk != av->top) { /* get and clear inuse bit */ clear_previnuse(nextchunk); /* consolidate forward */ if (!inuse(nextchunk)) { /* if mmap is used instead of sbrk, we may have a * chunk with !nextchunk->fd && !nextchunk->bk */ if (nextchunk->fd && nextchunk->fd) { unlink(nextchunk, bck, fwd); size += nextsize; set_head(p, size | PREV_INUSE); hashtable_skiprm(p, nextchunk); freecilst_add (nextchunk); } } set_head(p, size | PREV_INUSE); next = next_chunkinfo(p); if (next) next->prev_size = size; /* Place the chunk in unsorted chunk list. Chunks are not placed into regular bins until after they have been given one chance to be used in malloc. */ bck = unsorted_chunks(av); fwd = bck->fd; p->bk = bck; p->fd = fwd; bck->fd = p; fwd->bk = p; nextchunk = next_chunkinfo(p); if (nextchunk) nextchunk->prev_size = chunksize(p); check_free_chunk(p); } /* If the chunk borders the current high end of memory, consolidate into top */ else { size += nextsize; set_head(p, size | PREV_INUSE); hashtable_remove(chunk(av->top)); freecilst_add(av->top); av->top = p; check_chunk(p); } } /* if (nextchunk) */ /* If freeing a large space, consolidate possibly-surrounding chunks. Then, if the total unused topmost memory exceeds trim threshold, ask malloc_trim to reduce top. Unless max_fast is 0, we don't know if there are fastbins bordering top, so we cannot tell for sure whether threshold has been reached unless fastbins are consolidated. But we don't want to consolidate on each free. As a compromise, consolidation is performed if FASTBIN_CONSOLIDATION_THRESHOLD is reached. */ if (UNLIKELY((CHUNK_SIZE_T)(size) >= FASTBIN_CONSOLIDATION_THRESHOLD)) { if (have_fastchunks(av)) malloc_consolidate(av); #ifndef MORECORE_CANNOT_TRIM if ((CHUNK_SIZE_T)(chunksize(av->top)) >= (CHUNK_SIZE_T)(av->trim_threshold)) { if (morecore32bit(av)) { #ifdef DNMALLOC_DEBUG fprintf(stderr, "Calling systrim from free()\n"); #endif sYSTRIm(av->top_pad, av); #ifdef DNMALLOC_DEBUG fprintf(stderr, "Systrim done\n"); #endif } } #endif } } /* If the chunk was allocated via mmap, release via munmap() Note that if HAVE_MMAP is false but chunk_is_mmapped is true, then user must have overwritten memory. There's nothing we can do to catch this error unless DEBUG is set, in which case check_inuse_chunk (above) will have triggered error. */ else { #if PARANOIA > 0 int ret; #endif INTERNAL_SIZE_T offset = (INTERNAL_SIZE_T) p->hash_next; av->n_mmaps--; av->mmapped_mem -= (size + offset); #if PARANOIA > 0 ret = munmap((char*) chunk(p) - offset, size + offset); #else munmap((char*) chunk(p) - offset, size + offset); #endif hashtable_remove_mmapped(chunk(p)); freecilst_add(p); /* munmap returns non-zero on failure */ assert(ret == 0); } } } /* ------------------------- malloc_consolidate ------------------------- malloc_consolidate is a specialized version of free() that tears down chunks held in fastbins. Free itself cannot be used for this purpose since, among other things, it might place chunks back onto fastbins. So, instead, we need to use a minor variant of the same code. Also, because this routine needs to be called the first time through malloc anyway, it turns out to be the perfect place to trigger initialization code. */ #if __STD_C static void malloc_consolidate(mstate av) #else static void malloc_consolidate(av) mstate av; #endif { mfastbinptr* fb; /* current fastbin being consolidated */ mfastbinptr* maxfb; /* last fastbin (for loop control) */ chunkinfoptr p; /* current chunk being consolidated */ chunkinfoptr nextp; /* next chunk to consolidate */ chunkinfoptr prevp; chunkinfoptr unsorted_bin; /* bin header */ chunkinfoptr first_unsorted; /* chunk to link to */ /* These have same use as in free() */ chunkinfoptr nextchunk; INTERNAL_SIZE_T size; INTERNAL_SIZE_T nextsize; INTERNAL_SIZE_T prevsize; chunkinfoptr bck; chunkinfoptr fwd; chunkinfoptr next; /* If max_fast is 0, we know that av hasn't yet been initialized, in which case do so below */ if (av && av->max_fast != 0) { clear_fastchunks(av); unsorted_bin = unsorted_chunks(av); /* Remove each chunk from fast bin and consolidate it, placing it then in unsorted bin. Among other reasons for doing this, placing in unsorted bin avoids needing to calculate actual bins until malloc is sure that chunks aren't immediately going to be reused anyway. */ maxfb = &(av->fastbins[fastbin_index(av->max_fast)]); fb = &(av->fastbins[0]); do { if ( UNLIKELY((p = *fb) != 0)) { *fb = 0; do { check_inuse_chunk(p); nextp = p->fd; /* * Slightly streamlined version of consolidation code in free() */ size = chunksize(p); nextchunk = next_chunkinfo(p); /* gcc doesn't notice that it's only used if (nextchunk) */ if (nextchunk) nextsize = chunksize(nextchunk); else nextsize = 0; if (!prev_inuse(p)) { prevp = prev_chunkinfo(p); prevsize = chunksize(prevp); size += prevsize; #ifdef DNMALLOC_CHECKS if (inuse(prevp)) { fprintf(stderr, "Dnmalloc error: trying to unlink an inuse chunk (2): %p (chunk: %p)\n This is definitely a bug, please report it to dnmalloc@fort-knox.org.\n", prevp, chunk(prevp)); abort(); } #else assert(!inuse(prevp)); #endif unlink(prevp, bck, fwd); set_head(p, size | PREV_INUSE); hashtable_skiprm(prevp,p); freecilst_add(p); p=prevp; } if (nextchunk) { if (nextchunk != av->top) { clear_previnuse(nextchunk); /* if mmap is used instead of sbrk, we may have a * chunk with !nextchunk->fd && !nextchunk->bk */ if (!inuse(nextchunk)) { if( nextchunk->fd && nextchunk->bk) { size += nextsize; unlink(nextchunk, bck, fwd); set_head(p, size | PREV_INUSE); hashtable_skiprm(p,nextchunk); freecilst_add(nextchunk); } } first_unsorted = unsorted_bin->fd; unsorted_bin->fd = p; first_unsorted->bk = p; set_head(p, size | PREV_INUSE); p->bk = unsorted_bin; p->fd = first_unsorted; next = next_chunkinfo(p); if (next) next->prev_size = size; } else if (nextchunk == av->top) { size += nextsize; set_head(p, size | PREV_INUSE); hashtable_remove(chunk(av->top)); freecilst_add(av->top); av->top = p; } } /* if (nextchunk) */ } while ( (p = nextp) != 0); } } while (fb++ != maxfb); } else { /* Initialize dnmalloc */ dnmalloc_init(); malloc_init_state(get_malloc_state()); check_malloc_state(); } } /* ------------------------------ realloc ------------------------------ */ #if __STD_C DL_STATIC Void_t* rEALLOc(Void_t* oldmem, size_t bytes) #else DL_STATIC Void_t* rEALLOc(oldmem, bytes) Void_t* oldmem; size_t bytes; #endif { mstate av = get_malloc_state(); INTERNAL_SIZE_T nb; /* padded request size */ chunkinfoptr oldp; /* chunk corresponding to oldmem */ INTERNAL_SIZE_T oldsize; /* its size */ chunkinfoptr newp; /* chunk to return */ INTERNAL_SIZE_T newsize; /* its size */ Void_t* newmem; /* corresponding user mem */ chunkinfoptr next; /* next contiguous chunk after oldp */ chunkinfoptr remainder; /* extra space at end of newp */ CHUNK_SIZE_T remainder_size; /* its size */ chunkinfoptr bck; /* misc temp for linking */ chunkinfoptr fwd; /* misc temp for linking */ CHUNK_SIZE_T copysize; /* bytes to copy */ unsigned int ncopies; /* INTERNAL_SIZE_T words to copy */ INTERNAL_SIZE_T* s; /* copy source */ INTERNAL_SIZE_T* d; /* copy destination */ #ifdef REALLOC_ZERO_BYTES_FREES if (UNLIKELY(bytes == 0)) { fREe(oldmem); return 0; } #endif if (UNLIKELY(!av || av->max_fast == 0)) { malloc_consolidate(av); av = get_malloc_state(); } /* realloc of null is supposed to be same as malloc */ if (UNLIKELY(oldmem == 0)) return mALLOc(bytes); checked_request2size(bytes, nb); oldp = hashtable_lookup(oldmem); if (UNLIKELY(!oldp || !inuse(oldp))){ /* attempt to either realloc memory not managed by us * or memory that is not in use */ #ifdef DNMALLOC_CHECKS if (oldp) { fprintf(stderr, "Attempt to free memory not in use\n"); abort(); } else { fprintf(stderr, "Attempt to free memory not allocated\n"); abort(); } #endif assert(oldp && inuse(oldp)); return 0; } VALGRIND_FREELIKE_BLOCK(oldmem, 0); guard_check(av->guard_stored, oldp); oldsize = chunksize(oldp); check_inuse_chunk(oldp); if (!chunk_is_mmapped(oldp)) { if (UNLIKELY((CHUNK_SIZE_T)(oldsize) >= (CHUNK_SIZE_T)(nb))) { /* already big enough; split below */ newp = oldp; newsize = oldsize; } else { next = next_chunkinfo(oldp); if (next) next->prev_size = oldsize; /* Try to expand forward into top */ if (next && next == av->top && (CHUNK_SIZE_T)(newsize = oldsize + chunksize(next)) >= (CHUNK_SIZE_T)(nb + MINSIZE)) { set_head_size(oldp, nb); hashtable_remove(chunk(av->top)); av->top->chunk = chunk_at_offset(chunk(oldp), nb); set_head(av->top, (newsize - nb) | PREV_INUSE); /* av->top->chunk has been moved move in hashtable */ hashtable_insert(oldp, av->top); guard_set(av->guard_stored, oldp, bytes, nb); VALGRIND_MALLOCLIKE_BLOCK(chunk(oldp), bytes, 0, 0); return chunk(oldp); } /* Try to expand forward into next chunk; split off remainder below */ else if (next && next != av->top && !inuse(next) && (CHUNK_SIZE_T)(newsize = oldsize + chunksize(next)) >= (CHUNK_SIZE_T)(nb)) { newp = oldp; unlink(next, bck, fwd); hashtable_remove(chunk(next)); freecilst_add(next); next = next_chunkinfo(oldp); if (next) next->prev_size = newsize; } /* allocate, copy, free */ else { newmem = mALLOc(nb - MALLOC_ALIGN_MASK); if (newmem == 0) return 0; /* propagate failure */ newp = hashtable_lookup(newmem); newsize = chunksize(newp); /* next = next_chunkinfo(oldp); *//* 'next' never used rw 19.05.2008 */ /* Avoid copy if newp is next chunk after oldp. */ if (UNLIKELY(is_next_chunk(oldp, newp))) { newsize += oldsize; set_head_size(oldp, newsize); hashtable_skiprm(oldp, newp); freecilst_add(newp); newp = oldp; } else { /* Unroll copy of <= 40 bytes (80 if 8byte sizes) We know that contents have an even number of INTERNAL_SIZE_T-sized words; minimally 4 (2 on amd64). */ VALGRIND_MALLOCLIKE_BLOCK(chunk(oldp), chunksize(oldp), 0, 0); copysize = oldsize; s = (INTERNAL_SIZE_T*)(oldmem); d = (INTERNAL_SIZE_T*)(newmem); ncopies = copysize / sizeof(INTERNAL_SIZE_T); assert(ncopies >= 2); if (ncopies > 10) MALLOC_COPY(d, s, copysize); else { *(d+0) = *(s+0); *(d+1) = *(s+1); if (ncopies > 2) { *(d+2) = *(s+2); *(d+3) = *(s+3); if (ncopies > 4) { *(d+4) = *(s+4); *(d+5) = *(s+5); if (ncopies > 6) { *(d+6) = *(s+6); *(d+7) = *(s+7); if (ncopies > 8) { *(d+8) = *(s+8); *(d+9) = *(s+9); } } } } } fREe(oldmem); check_inuse_chunk(newp); guard_set(av->guard_stored, newp, bytes, nb); return chunk(newp); } } } /* If possible, free extra space in old or extended chunk */ assert((CHUNK_SIZE_T)(newsize) >= (CHUNK_SIZE_T)(nb)); remainder_size = newsize - nb; if (remainder_size >= MINSIZE) { /* split remainder */ remainder = cireg_getfree(); remainder->chunk = chunk_at_offset(chunk(newp), nb); set_head_size(newp, nb); set_head(remainder, remainder_size | PREV_INUSE | INUSE); remainder->prev_size = nb; hashtable_insert(newp, remainder); /* Mark remainder as inuse so free() won't complain */ set_all_inuse(remainder); guard_set(av->guard_stored, remainder, 0, remainder_size); VALGRIND_MALLOCLIKE_BLOCK(chunk(remainder), remainder_size, 0, 0); fREe(chunk(remainder)); } else { /* not enough extra to split off */ set_head_size(newp, newsize); set_all_inuse(newp); } check_inuse_chunk(newp); guard_set(av->guard_stored, newp, bytes, nb); VALGRIND_MALLOCLIKE_BLOCK(chunk(newp), bytes, 0, 0); return chunk(newp); } /* Handle mmap cases */ else { #if HAVE_MREMAP INTERNAL_SIZE_T offset = (INTERNAL_SIZE_T) oldp->hash_next; size_t pagemask = av->pagesize - 1; char *cp; CHUNK_SIZE_T sum; /* Note the extra SIZE_SZ overhead */ /* newsize = (nb + offset + SIZE_SZ + pagemask) & ~pagemask; */ newsize = (nb + offset + pagemask) & ~pagemask; /* don't need to remap if still within same page */ if (oldsize == newsize - offset) { guard_set(av->guard_stored, oldp, bytes, nb); VALGRIND_FREELIKE_BLOCK(oldmem, 0); VALGRIND_MALLOCLIKE_BLOCK(oldmem, bytes, 0, 0); return oldmem; } cp = (char*)mremap((char*)chunk(oldp) - offset, oldsize + offset, newsize, 1); if (cp != (char*)MORECORE_FAILURE) { hashtable_remove_mmapped(chunk(oldp)); oldp->chunk = (mchunkptr)(cp + offset); set_head(oldp, (newsize - offset)|IS_MMAPPED|INUSE); hashtable_add(oldp); assert(aligned_OK(chunk(oldp))); /* rw fix: newp -> oldp */ assert(( ((INTERNAL_SIZE_T) oldp->hash_next) == offset)); /* update statistics */ sum = av->mmapped_mem += newsize - oldsize; if (sum > (CHUNK_SIZE_T)(av->max_mmapped_mem)) av->max_mmapped_mem = sum; sum += av->sbrked_mem; if (sum > (CHUNK_SIZE_T)(av->max_total_mem)) av->max_total_mem = sum; guard_set(av->guard_stored, oldp, bytes, nb); VALGRIND_FREELIKE_BLOCK(oldmem, 0); VALGRIND_MALLOCLIKE_BLOCK(chunk(oldp), bytes, 0, 0); return chunk(oldp); } #endif /* have MREMAP */ /* Note the extra SIZE_SZ overhead. */ if ((CHUNK_SIZE_T)(oldsize) >= (CHUNK_SIZE_T)(nb + SIZE_SZ)) newmem = oldmem; /* do nothing */ else { /* Must alloc, copy, free. */ newmem = mALLOc(nb - MALLOC_ALIGN_MASK); if (newmem != 0) { MALLOC_COPY(newmem, oldmem, oldsize); fREe(oldmem); } } VALGRIND_MALLOCLIKE_BLOCK(newmem, bytes, 0, 0); guard_set(av->guard_stored, mem2chunk(newmem), bytes, nb); return newmem; } } /* ---------------------------posix_memalign ---------------------------- */ #if __STD_C DL_STATIC int posix_mEMALIGn(Void_t** memptr, size_t alignment, size_t bytes) #else DL_STATIC int posix_mEMALIGn(memptr, alignment, bytes) Void_t** memptr; size_t alignment; size_t bytes; #endif { mstate av; if (alignment % sizeof(void *) != 0) return EINVAL; if ((alignment & (alignment - 1)) != 0) return EINVAL; av = get_malloc_state(); if (!av || av->max_fast == 0) malloc_consolidate(av); *memptr = mEMALIGn(alignment, bytes); return (*memptr != NULL ? 0 : ENOMEM); } /* ------------------------------ memalign ------------------------------ */ #if __STD_C DL_STATIC Void_t* mEMALIGn(size_t alignment, size_t bytes) #else DL_STATIC Void_t* mEMALIGn(alignment, bytes) size_t alignment; size_t bytes; #endif { INTERNAL_SIZE_T nb; /* padded request size */ char* m; /* memory returned by malloc call */ chunkinfoptr p; /* corresponding chunk */ char* brk; /* alignment point within p */ chunkinfoptr newp; /* chunk to return */ INTERNAL_SIZE_T newsize; /* its size */ INTERNAL_SIZE_T leadsize; /* leading space before alignment point */ chunkinfoptr remainder; /* spare room at end to split off */ CHUNK_SIZE_T remainder_size; /* its size */ INTERNAL_SIZE_T size; #if PARANOIA > 2 mstate av; #endif /* If need less alignment than we give anyway, just relay to malloc */ if (UNLIKELY(alignment <= MALLOC_ALIGNMENT)) return mALLOc(bytes); /* Otherwise, ensure that it is at least a minimum chunk size */ if (alignment < MINSIZE) alignment = MINSIZE; /* Make sure alignment is power of 2 (in case MINSIZE is not). */ if (UNLIKELY((alignment & (alignment - 1)) != 0)) { size_t a = MALLOC_ALIGNMENT * 2; while ((CHUNK_SIZE_T)a < (CHUNK_SIZE_T)alignment) a <<= 1; alignment = a; } checked_request2size(bytes, nb); /* Strategy: find a spot within that chunk that meets the alignment request, and then possibly free the leading and trailing space. */ /* Call malloc with worst case padding to hit alignment. */ m = (char*)(mALLOc(nb + alignment + MINSIZE)); if (m == 0) return 0; /* propagate failure */ #if PARANOIA > 2 av = get_malloc_state(); #endif p = hashtable_lookup((mchunkptr) m); if ((((PTR_UINT)(m)) % alignment) != 0) { /* misaligned */ /* Find an aligned spot inside chunk. Since we need to give back leading space in a chunk of at least MINSIZE, if the first calculation places us at a spot with less than MINSIZE leader, we can move to the next aligned spot -- we've allocated enough total room so that this is always possible. */ brk = (char*) ((PTR_UINT)(((PTR_UINT)(m + alignment - 1)) & -((signed long) alignment))); if ((CHUNK_SIZE_T)(brk - (char*)(chunk(p))) < MINSIZE) brk += alignment; newp = cireg_getfree(); newp->chunk = (mchunkptr)brk; leadsize = brk - (char*)(chunk(p)); newsize = chunksize(p) - leadsize; /* For mmapped chunks, just adjust offset */ if (UNLIKELY(chunk_is_mmapped(p))) { newp->hash_next = (chunkinfoptr) (((INTERNAL_SIZE_T) p->hash_next) + leadsize); set_head(newp, newsize|IS_MMAPPED|INUSE); hashtable_remove_mmapped(chunk(p)); freecilst_add(p); hashtable_add(newp); guard_set(av->guard_stored, newp, bytes, nb); return chunk(newp); } /* Otherwise, give back leader, use the rest */ set_head(newp, newsize | PREV_INUSE | INUSE); set_head_size(p, leadsize); set_all_inuse(newp); hashtable_add(newp); /* 20.05.2008 rw */ guard_set(av->guard_stored, p, 0, leadsize); fREe(chunk(p)); p = newp; assert (newsize >= nb && (((PTR_UINT)(chunk(p))) % alignment) == 0); } /* Also give back spare room at the end */ if (!chunk_is_mmapped(p)) { size = chunksize(p); if ((CHUNK_SIZE_T)(size) > (CHUNK_SIZE_T)(nb + MINSIZE)) { remainder = cireg_getfree(); remainder_size = size - nb; remainder->chunk = chunk_at_offset(chunk(p), nb); set_head(remainder, remainder_size | PREV_INUSE | INUSE); set_head_size(p, nb); hashtable_add(remainder); /* 20.05.2008 rw */ guard_set(av->guard_stored, remainder, 0, remainder_size); fREe(chunk(remainder)); } } check_inuse_chunk(p); guard_set(av->guard_stored, p, bytes, nb); return chunk(p); } /* ------------------------------ calloc ------------------------------ */ #if __STD_C DL_STATIC Void_t* cALLOc(size_t n_elements, size_t elem_size) #else DL_STATIC Void_t* cALLOc(n_elements, elem_size) size_t n_elements; size_t elem_size; #endif { chunkinfoptr p; CHUNK_SIZE_T clearsize; CHUNK_SIZE_T nclears; INTERNAL_SIZE_T* d; Void_t* mem; mem = mALLOc(n_elements * elem_size); if (mem != 0) { p = hashtable_lookup(mem); if (!chunk_is_mmapped(p)) { /* Unroll clear of <= 40 bytes (80 if 8byte sizes) We know that contents have an even number of INTERNAL_SIZE_T-sized words; minimally 4 (2 on amd64). */ d = (INTERNAL_SIZE_T*)mem; clearsize = chunksize(p); nclears = clearsize / sizeof(INTERNAL_SIZE_T); assert(nclears >= 2); if (nclears > 10) { MALLOC_ZERO(d, clearsize); } else { *(d+0) = 0; *(d+1) = 0; if (nclears > 2) { *(d+2) = 0; *(d+3) = 0; if (nclears > 4) { *(d+4) = 0; *(d+5) = 0; if (nclears > 6) { *(d+6) = 0; *(d+7) = 0; if (nclears > 8) { *(d+8) = 0; *(d+9) = 0; } } } } } } #if ! MMAP_CLEARS else { d = (INTERNAL_SIZE_T*)mem; clearsize = chunksize(p); MALLOC_ZERO(d, clearsize); } #endif /* Set guard again, since we just cleared it */ guard_set(get_malloc_state()->guard_stored, p, (n_elements * elem_size), p->size); } return mem; } /* ------------------------------ valloc ------------------------------ */ #if __STD_C DL_STATIC Void_t* vALLOc(size_t bytes) #else DL_STATIC Void_t* vALLOc(bytes) size_t bytes; #endif { /* Ensure initialization */ mstate av = get_malloc_state(); if (!av || av->max_fast == 0) { malloc_consolidate(av); av = get_malloc_state(); } return mEMALIGn(av->pagesize, bytes); } /* ------------------------------ pvalloc ------------------------------ */ #if __STD_C DL_STATIC Void_t* pVALLOc(size_t bytes) #else DL_STATIC Void_t* pVALLOc(bytes) size_t bytes; #endif { mstate av = get_malloc_state(); size_t pagesz; /* Ensure initialization */ if (!av || av->max_fast == 0) { malloc_consolidate(av); av = get_malloc_state(); } pagesz = av->pagesize; return mEMALIGn(pagesz, (bytes + pagesz - 1) & ~(pagesz - 1)); } /* ------------------------------ malloc_trim ------------------------------ */ #if __STD_C DL_STATIC int mTRIm(size_t pad) #else DL_STATIC int mTRIm(pad) size_t pad; #endif { mstate av = get_malloc_state(); /* Ensure initialization/consolidation */ malloc_consolidate(av); av = get_malloc_state(); #ifndef MORECORE_CANNOT_TRIM if (morecore32bit(av)) return sYSTRIm(pad, av); else return 0; #else return 0; #endif } /* ------------------------- malloc_usable_size ------------------------- */ #if __STD_C DL_STATIC size_t mUSABLe(Void_t* mem) #else DL_STATIC size_t mUSABLe(mem) Void_t* mem; #endif { chunkinfoptr p; if (mem != 0) { p = hashtable_lookup(mem); if (p && inuse(p)) return chunksize(p); } return 0; } /* ------------------------------ mallinfo ------------------------------ */ DL_STATIC struct mallinfo2 mALLINFo2() { mstate av = get_malloc_state(); static struct mallinfo2 mi; unsigned int i; mbinptr b; chunkinfoptr p; INTERNAL_SIZE_T avail; INTERNAL_SIZE_T fastavail; int nblocks; int nfastblocks; /* Ensure initialization */ if (!av || av->top == 0) { malloc_consolidate(av); av = get_malloc_state(); } check_malloc_state(); if (!av || av->top == 0) { return mi; } /* Account for top */ avail = chunksize(av->top); nblocks = 1; /* top always exists */ /* traverse fastbins */ nfastblocks = 0; fastavail = 0; for (i = 0; i < NFASTBINS; ++i) { for (p = av->fastbins[i]; p != 0; p = p->fd) { ++nfastblocks; fastavail += chunksize(p); } } avail += fastavail; /* traverse regular bins */ for (i = 1; i < NBINS; ++i) { b = bin_at(av, i); for (p = last(b); p != b; p = p->bk) { ++nblocks; avail += chunksize(p); } } mi.smblks = nfastblocks; mi.ordblks = nblocks; mi.fordblks = avail; mi.uordblks = av->sbrked_mem - avail; mi.arena = av->sbrked_mem; mi.hblks = av->n_mmaps; mi.hblkhd = av->mmapped_mem; mi.fsmblks = fastavail; mi.keepcost = chunksize(av->top); mi.usmblks = av->max_total_mem; return mi; } /* ------------------------------ malloc_stats ------------------------------ */ DL_STATIC void mSTATs() { struct mallinfo2 mi = mALLINFo2(); fprintf(stderr, "hashtable = %10lu MB\n", (CHUNK_SIZE_T)(HASHTABLESIZE / (1024*1024))); fprintf(stderr, "max system bytes = %10lu\n", (CHUNK_SIZE_T)(mi.usmblks)); fprintf(stderr, "system bytes = %10lu (%10lu sbrked, %10lu mmaped)\n", (CHUNK_SIZE_T)(mi.arena + mi.hblkhd), (CHUNK_SIZE_T)(mi.arena), (CHUNK_SIZE_T)(mi.hblkhd)); fprintf(stderr, "in use bytes = %10lu\n", (CHUNK_SIZE_T)(mi.uordblks + mi.hblkhd)); } /* ------------------------------ mallopt ------------------------------ */ #if __STD_C DL_STATIC int mALLOPt(int param_number, int value) #else DL_STATIC int mALLOPt(param_number, value) int param_number; int value; #endif { mstate av = get_malloc_state(); /* Ensure initialization/consolidation */ malloc_consolidate(av); av = get_malloc_state(); switch(param_number) { case M_MXFAST: if (value >= 0 && value <= MAX_FAST_SIZE) { set_max_fast(av, value); return 1; } else return 0; case M_TRIM_THRESHOLD: av->trim_threshold = value; return 1; case M_TOP_PAD: av->top_pad = value; return 1; case M_MMAP_THRESHOLD: av->mmap_threshold = value; return 1; case M_MMAP_MAX: if (value != 0) return 0; av->n_mmaps_max = value; return 1; default: return 0; } } /* $OpenBSD: arc4random.c,v 1.19 2008/06/04 00:50:23 djm Exp $ */ /* * Copyright (c) 1996, David Mazieres * Copyright (c) 2008, Damien Miller * * Permission to use, copy, modify, and distribute this software for any * purpose with or without fee is hereby granted, provided that the above * copyright notice and this permission notice appear in all copies. * * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */ /* * Arc4 random number generator for OpenBSD. * * This code is derived from section 17.1 of Applied Cryptography, * second edition, which describes a stream cipher allegedly * compatible with RSA Labs "RC4" cipher (the actual description of * which is a trade secret). The same algorithm is used as a stream * cipher called "arcfour" in Tatu Ylonen's ssh package. * * Here the stream cipher has been modified always to include the time * when initializing the state. That makes it impossible to * regenerate the same random sequence twice, so this can't be used * for encryption, but will generate good random numbers. * * RC4 is a registered trademark of RSA Laboratories. */ /* Moved u_int8_t -> unsigned char (portability) * Eliminated unneeded functions, added read from /dev/urandom taken from: $MirOS: contrib/code/Snippets/arc4random.c,v 1.3 2008-03-04 22:53:14 tg Exp $ * Modified by Robert Connolly from OpenBSD lib/libc/crypt/arc4random.c v1.11. * This is arc4random(3) using urandom. */ #include #include #include #include #include struct arc4_stream { unsigned char i; unsigned char j; unsigned char s[256]; }; static int rs_initialized; static struct arc4_stream rs; static pid_t arc4_stir_pid; static int arc4_count; static unsigned char arc4_getbyte(void); static void arc4_init(void) { int n; for (n = 0; n < 256; n++) rs.s[n] = n; rs.i = 0; rs.j = 0; } static inline void arc4_addrandom(unsigned char *dat, int datlen) { int n; unsigned char si; rs.i--; for (n = 0; n < 256; n++) { rs.i = (rs.i + 1); si = rs.s[rs.i]; rs.j = (rs.j + si + dat[n % datlen]); rs.s[rs.i] = rs.s[rs.j]; rs.s[rs.j] = si; } rs.j = rs.i; } #ifdef HAVE_SCHED_H #include #endif static void arc4_stir(void) { int i; struct { struct timeval tv1; struct timeval tv2; unsigned char rnd[(128 - 2*sizeof(struct timeval)) / sizeof(unsigned char)]; } rdat; #if !defined(__FreeBSD__) && !defined(__OpenBSD__) && !defined(__NetBSD__) ssize_t sz = 0; int fd; #endif gettimeofday(&rdat.tv1, NULL); if (!rs_initialized) { arc4_init(); rs_initialized = 1; } #if !defined(__FreeBSD__) && !defined(__OpenBSD__) && !defined(__NetBSD__) #ifdef HAVE_SCHED_YIELD /* Yield the processor to introduce some random delay. */ (void) sched_yield(); #endif /* * Pthread problem in multithreaded code on *BSD. */ fd = open("/dev/urandom", O_RDONLY); if (fd != -1) { sz = (size_t)read(fd, rdat.rnd, sizeof (rdat.rnd)); /* * gcc complains if we ignore the return value of read(), and * the llvm/clang analyzer complains if we don't use it... */ if (sz > (-256)) /* always true */ close(fd); } /* if (sz > sizeof (rdat.rnd)) sz = 0; */ #endif arc4_stir_pid = getpid(); gettimeofday(&rdat.tv2, NULL); arc4_addrandom((void *)&rdat, sizeof(rdat)); /* * Discard early keystream, as per recommendations in: * http://www.wisdom.weizmann.ac.il/~itsik/RC4/Papers/Rc4_ksa.ps */ for (i = 0; i < 256; i++) (void)arc4_getbyte(); arc4_count = 1600000; } static unsigned char arc4_getbyte(void) { unsigned char si, sj; rs.i = (rs.i + 1); si = rs.s[rs.i]; rs.j = (rs.j + si); sj = rs.s[rs.j]; rs.s[rs.i] = sj; rs.s[rs.j] = si; return (rs.s[(si + sj) & 0xff]); } /* Changed to return char* */ static char * dnmalloc_arc4random(void) { static char val[4]; /* We only call this once, hence no need for locking. */ /* _ARC4_LOCK(); */ arc4_count -= 4; if (arc4_count <= 0 || !rs_initialized || arc4_stir_pid != getpid()) arc4_stir(); val[0] = (char) arc4_getbyte(); val[1] = (char) arc4_getbyte(); val[2] = (char) arc4_getbyte(); val[3] = (char) arc4_getbyte(); arc4_stir(); /* _ARC4_UNLOCK(); */ return val; } #else int dnmalloc_pthread_init() { return 0; } #endif /* ! USE_SYSTEM_MALLOC */