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Diffstat (limited to 'roms/u-boot/common/dlmalloc.c')
| -rw-r--r-- | roms/u-boot/common/dlmalloc.c | 2549 |
1 files changed, 2549 insertions, 0 deletions
diff --git a/roms/u-boot/common/dlmalloc.c b/roms/u-boot/common/dlmalloc.c new file mode 100644 index 000000000..11729e8c8 --- /dev/null +++ b/roms/u-boot/common/dlmalloc.c @@ -0,0 +1,2549 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * This code is based on a version (aka dlmalloc) of malloc/free/realloc written + * by Doug Lea and released to the public domain, as explained at + * http://creativecommons.org/publicdomain/zero/1.0/- + * + * The original code is available at http://gee.cs.oswego.edu/pub/misc/ + * as file malloc-2.6.6.c. + */ + +#include <common.h> +#include <log.h> +#include <asm/global_data.h> + +#if CONFIG_IS_ENABLED(UNIT_TEST) +#define DEBUG +#endif + +#include <malloc.h> +#include <asm/io.h> + +#ifdef DEBUG +#if __STD_C +static void malloc_update_mallinfo (void); +void malloc_stats (void); +#else +static void malloc_update_mallinfo (); +void malloc_stats(); +#endif +#endif /* DEBUG */ + +DECLARE_GLOBAL_DATA_PTR; + +/* + Emulation of sbrk for WIN32 + All code within the ifdef WIN32 is untested by me. + + Thanks to Martin Fong and others for supplying this. +*/ + + +#ifdef WIN32 + +#define AlignPage(add) (((add) + (malloc_getpagesize-1)) & \ +~(malloc_getpagesize-1)) +#define AlignPage64K(add) (((add) + (0x10000 - 1)) & ~(0x10000 - 1)) + +/* resrve 64MB to insure large contiguous space */ +#define RESERVED_SIZE (1024*1024*64) +#define NEXT_SIZE (2048*1024) +#define TOP_MEMORY ((unsigned long)2*1024*1024*1024) + +struct GmListElement; +typedef struct GmListElement GmListElement; + +struct GmListElement +{ + GmListElement* next; + void* base; +}; + +static GmListElement* head = 0; +static unsigned int gNextAddress = 0; +static unsigned int gAddressBase = 0; +static unsigned int gAllocatedSize = 0; + +static +GmListElement* makeGmListElement (void* bas) +{ + GmListElement* this; + this = (GmListElement*)(void*)LocalAlloc (0, sizeof (GmListElement)); + assert (this); + if (this) + { + this->base = bas; + this->next = head; + head = this; + } + return this; +} + +void gcleanup () +{ + BOOL rval; + assert ( (head == NULL) || (head->base == (void*)gAddressBase)); + if (gAddressBase && (gNextAddress - gAddressBase)) + { + rval = VirtualFree ((void*)gAddressBase, + gNextAddress - gAddressBase, + MEM_DECOMMIT); + assert (rval); + } + while (head) + { + GmListElement* next = head->next; + rval = VirtualFree (head->base, 0, MEM_RELEASE); + assert (rval); + LocalFree (head); + head = next; + } +} + +static +void* findRegion (void* start_address, unsigned long size) +{ + MEMORY_BASIC_INFORMATION info; + if (size >= TOP_MEMORY) return NULL; + + while ((unsigned long)start_address + size < TOP_MEMORY) + { + VirtualQuery (start_address, &info, sizeof (info)); + if ((info.State == MEM_FREE) && (info.RegionSize >= size)) + return start_address; + else + { + /* Requested region is not available so see if the */ + /* next region is available. Set 'start_address' */ + /* to the next region and call 'VirtualQuery()' */ + /* again. */ + + start_address = (char*)info.BaseAddress + info.RegionSize; + + /* Make sure we start looking for the next region */ + /* on the *next* 64K boundary. Otherwise, even if */ + /* the new region is free according to */ + /* 'VirtualQuery()', the subsequent call to */ + /* 'VirtualAlloc()' (which follows the call to */ + /* this routine in 'wsbrk()') will round *down* */ + /* the requested address to a 64K boundary which */ + /* we already know is an address in the */ + /* unavailable region. Thus, the subsequent call */ + /* to 'VirtualAlloc()' will fail and bring us back */ + /* here, causing us to go into an infinite loop. */ + + start_address = + (void *) AlignPage64K((unsigned long) start_address); + } + } + return NULL; + +} + + +void* wsbrk (long size) +{ + void* tmp; + if (size > 0) + { + if (gAddressBase == 0) + { + gAllocatedSize = max (RESERVED_SIZE, AlignPage (size)); + gNextAddress = gAddressBase = + (unsigned int)VirtualAlloc (NULL, gAllocatedSize, + MEM_RESERVE, PAGE_NOACCESS); + } else if (AlignPage (gNextAddress + size) > (gAddressBase + +gAllocatedSize)) + { + long new_size = max (NEXT_SIZE, AlignPage (size)); + void* new_address = (void*)(gAddressBase+gAllocatedSize); + do + { + new_address = findRegion (new_address, new_size); + + if (!new_address) + return (void*)-1; + + gAddressBase = gNextAddress = + (unsigned int)VirtualAlloc (new_address, new_size, + MEM_RESERVE, PAGE_NOACCESS); + /* repeat in case of race condition */ + /* The region that we found has been snagged */ + /* by another thread */ + } + while (gAddressBase == 0); + + assert (new_address == (void*)gAddressBase); + + gAllocatedSize = new_size; + + if (!makeGmListElement ((void*)gAddressBase)) + return (void*)-1; + } + if ((size + gNextAddress) > AlignPage (gNextAddress)) + { + void* res; + res = VirtualAlloc ((void*)AlignPage (gNextAddress), + (size + gNextAddress - + AlignPage (gNextAddress)), + MEM_COMMIT, PAGE_READWRITE); + if (!res) + return (void*)-1; + } + tmp = (void*)gNextAddress; + gNextAddress = (unsigned int)tmp + size; + return tmp; + } + else if (size < 0) + { + unsigned int alignedGoal = AlignPage (gNextAddress + size); + /* Trim by releasing the virtual memory */ + if (alignedGoal >= gAddressBase) + { + VirtualFree ((void*)alignedGoal, gNextAddress - alignedGoal, + MEM_DECOMMIT); + gNextAddress = gNextAddress + size; + return (void*)gNextAddress; + } + else + { + VirtualFree ((void*)gAddressBase, gNextAddress - gAddressBase, + MEM_DECOMMIT); + gNextAddress = gAddressBase; + return (void*)-1; + } + } + else + { + return (void*)gNextAddress; + } +} + +#endif + + + +/* + Type declarations +*/ + + +struct malloc_chunk +{ + INTERNAL_SIZE_T prev_size; /* Size of previous chunk (if free). */ + INTERNAL_SIZE_T size; /* Size in bytes, including overhead. */ + struct malloc_chunk* fd; /* double links -- used only if free. */ + struct malloc_chunk* bk; +} __attribute__((__may_alias__)) ; + +typedef struct malloc_chunk* mchunkptr; + +/* + + malloc_chunk details: + + (The following includes lightly edited explanations by Colin Plumb.) + + Chunks of memory are maintained using a `boundary tag' method as + described in e.g., Knuth or Standish. (See the paper by Paul + Wilson ftp://ftp.cs.utexas.edu/pub/garbage/allocsrv.ps for a + survey of such techniques.) Sizes of free chunks are stored both + in the front of each chunk and at the end. This makes + consolidating fragmented chunks into bigger chunks very fast. The + size fields also hold bits representing whether chunks are free or + in use. + + An allocated chunk looks like this: + + + chunk-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Size of previous chunk, if allocated | | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Size of chunk, in bytes |P| + mem-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | User data starts here... . + . . + . (malloc_usable_space() bytes) . + . | +nextchunk-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Size of chunk | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + + + Where "chunk" is the front of the chunk for the purpose of most of + the malloc code, but "mem" is the pointer that is returned to the + user. "Nextchunk" is the beginning of the next contiguous chunk. + + Chunks always begin on even word boundries, so the mem portion + (which is returned to the user) is also on an even word boundary, and + thus double-word aligned. + + Free chunks are stored in circular doubly-linked lists, and look like this: + + chunk-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Size of previous chunk | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + `head:' | Size of chunk, in bytes |P| + mem-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Forward pointer to next chunk in list | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Back pointer to previous chunk in list | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Unused space (may be 0 bytes long) . + . . + . | + +nextchunk-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + `foot:' | Size of chunk, in bytes | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + + The P (PREV_INUSE) bit, stored in the unused low-order bit of the + chunk size (which is always a multiple of two words), is an in-use + bit for the *previous* chunk. If that bit is *clear*, then the + word before the current chunk size contains the previous chunk + size, and can be used to find the front of the previous chunk. + (The very first chunk allocated always has this bit set, + preventing access to non-existent (or non-owned) memory.) + + Note that the `foot' of the current chunk is actually represented + as the prev_size of the NEXT chunk. (This makes it easier to + deal with alignments etc). + + The two exceptions to all this are + + 1. The special chunk `top', which doesn't bother using the + trailing size field since there is no + next contiguous chunk that would have to index off it. (After + initialization, `top' is forced to always exist. If it would + become less than MINSIZE bytes long, it is replenished via + malloc_extend_top.) + + 2. Chunks allocated via mmap, which have the second-lowest-order + bit (IS_MMAPPED) set in their size fields. Because they are + never merged or traversed from any other chunk, they have no + foot size or inuse information. + + Available chunks are kept in any of several places (all declared below): + + * `av': An array of chunks serving as bin headers for consolidated + 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. All procedures maintain the invariant that no + consolidated chunk physically borders another one. Chunks in + bins are kept in size order, with ties going to the + approximately least recently used chunk. + + The chunks in each bin are maintained in decreasing sorted order by + size. This is irrelevant 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 or 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. + + * `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). + + * `last_remainder': A bin holding only the remainder of the + most recently split (non-top) chunk. This bin is checked + before other non-fitting chunks, so as to provide better + locality for runs of sequentially allocated chunks. + + * Implicitly, through the host system's memory mapping tables. + If supported, requests greater than a threshold are usually + serviced via calls to mmap, and then later released via munmap. + +*/ + +/* sizes, alignments */ + +#define SIZE_SZ (sizeof(INTERNAL_SIZE_T)) +#define MALLOC_ALIGNMENT (SIZE_SZ + SIZE_SZ) +#define MALLOC_ALIGN_MASK (MALLOC_ALIGNMENT - 1) +#define MINSIZE (sizeof(struct malloc_chunk)) + +/* conversion from malloc headers to user pointers, and back */ + +#define chunk2mem(p) ((Void_t*)((char*)(p) + 2*SIZE_SZ)) +#define mem2chunk(mem) ((mchunkptr)((char*)(mem) - 2*SIZE_SZ)) + +/* pad request bytes into a usable size */ + +#define request2size(req) \ + (((long)((req) + (SIZE_SZ + MALLOC_ALIGN_MASK)) < \ + (long)(MINSIZE + MALLOC_ALIGN_MASK)) ? MINSIZE : \ + (((req) + (SIZE_SZ + MALLOC_ALIGN_MASK)) & ~(MALLOC_ALIGN_MASK))) + +/* Check if m has acceptable alignment */ + +#define aligned_OK(m) (((unsigned long)((m)) & (MALLOC_ALIGN_MASK)) == 0) + + + + +/* + Physical chunk operations +*/ + + +/* size field is or'ed with PREV_INUSE when previous adjacent chunk in use */ + +#define PREV_INUSE 0x1 + +/* size field is or'ed with IS_MMAPPED if the chunk was obtained with mmap() */ + +#define IS_MMAPPED 0x2 + +/* Bits to mask off when extracting size */ + +#define SIZE_BITS (PREV_INUSE|IS_MMAPPED) + + +/* Ptr to next physical malloc_chunk. */ + +#define next_chunk(p) ((mchunkptr)( ((char*)(p)) + ((p)->size & ~PREV_INUSE) )) + +/* Ptr to previous physical malloc_chunk */ + +#define prev_chunk(p)\ + ((mchunkptr)( ((char*)(p)) - ((p)->prev_size) )) + + +/* Treat space at ptr + offset as a chunk */ + +#define chunk_at_offset(p, s) ((mchunkptr)(((char*)(p)) + (s))) + + + + +/* + Dealing with use bits +*/ + +/* extract p's inuse bit */ + +#define inuse(p)\ +((((mchunkptr)(((char*)(p))+((p)->size & ~PREV_INUSE)))->size) & PREV_INUSE) + +/* extract inuse bit of previous chunk */ + +#define prev_inuse(p) ((p)->size & PREV_INUSE) + +/* check for mmap()'ed chunk */ + +#define chunk_is_mmapped(p) ((p)->size & IS_MMAPPED) + +/* set/clear chunk as in use without otherwise disturbing */ + +#define set_inuse(p)\ +((mchunkptr)(((char*)(p)) + ((p)->size & ~PREV_INUSE)))->size |= PREV_INUSE + +#define clear_inuse(p)\ +((mchunkptr)(((char*)(p)) + ((p)->size & ~PREV_INUSE)))->size &= ~(PREV_INUSE) + +/* check/set/clear inuse bits in known places */ + +#define inuse_bit_at_offset(p, s)\ + (((mchunkptr)(((char*)(p)) + (s)))->size & PREV_INUSE) + +#define set_inuse_bit_at_offset(p, s)\ + (((mchunkptr)(((char*)(p)) + (s)))->size |= PREV_INUSE) + +#define clear_inuse_bit_at_offset(p, s)\ + (((mchunkptr)(((char*)(p)) + (s)))->size &= ~(PREV_INUSE)) + + + + +/* + Dealing with size fields +*/ + +/* Get size, ignoring use bits */ + +#define chunksize(p) ((p)->size & ~(SIZE_BITS)) + +/* Set size at head, without disturbing its use bit */ + +#define set_head_size(p, s) ((p)->size = (((p)->size & PREV_INUSE) | (s))) + +/* Set size/use ignoring previous bits in header */ + +#define set_head(p, s) ((p)->size = (s)) + +/* Set size at footer (only when chunk is not in use) */ + +#define set_foot(p, s) (((mchunkptr)((char*)(p) + (s)))->prev_size = (s)) + + + + + +/* + Bins + + The bins, `av_' are an array of pairs of pointers serving as the + heads of (initially empty) doubly-linked lists of chunks, laid out + in a way so that each pair can be treated as if it were in a + malloc_chunk. (This way, the fd/bk offsets for linking bin heads + and chunks are the same). + + Bins for sizes < 512 bytes contain chunks of all the same size, spaced + 8 bytes apart. Larger bins are approximately logarithmically + spaced. (See the table below.) The `av_' array is never mentioned + directly in the code, but instead via bin access macros. + + Bin layout: + + 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 + + There is actually a little bit of slop in the numbers in bin_index + for the sake of speed. This makes no difference elsewhere. + + The special chunks `top' and `last_remainder' get their own bins, + (this is implemented via yet more trickery with the av_ array), + although `top' is never properly linked to its bin since it is + always handled specially. + +*/ + +#define NAV 128 /* number of bins */ + +typedef struct malloc_chunk* mbinptr; + +/* access macros */ + +#define bin_at(i) ((mbinptr)((char*)&(av_[2*(i) + 2]) - 2*SIZE_SZ)) +#define next_bin(b) ((mbinptr)((char*)(b) + 2 * sizeof(mbinptr))) +#define prev_bin(b) ((mbinptr)((char*)(b) - 2 * sizeof(mbinptr))) + +/* + The first 2 bins are never indexed. The corresponding av_ cells are instead + used for bookkeeping. This is not to save space, but to simplify + indexing, maintain locality, and avoid some initialization tests. +*/ + +#define top (av_[2]) /* The topmost chunk */ +#define last_remainder (bin_at(1)) /* remainder from last split */ + + +/* + 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 in malloc_extend_top. +*/ + +#define initial_top ((mchunkptr)(bin_at(0))) + +/* Helper macro to initialize bins */ + +#define IAV(i) bin_at(i), bin_at(i) + +static mbinptr av_[NAV * 2 + 2] = { + NULL, NULL, + IAV(0), IAV(1), IAV(2), IAV(3), IAV(4), IAV(5), IAV(6), IAV(7), + IAV(8), IAV(9), IAV(10), IAV(11), IAV(12), IAV(13), IAV(14), IAV(15), + IAV(16), IAV(17), IAV(18), IAV(19), IAV(20), IAV(21), IAV(22), IAV(23), + IAV(24), IAV(25), IAV(26), IAV(27), IAV(28), IAV(29), IAV(30), IAV(31), + IAV(32), IAV(33), IAV(34), IAV(35), IAV(36), IAV(37), IAV(38), IAV(39), + IAV(40), IAV(41), IAV(42), IAV(43), IAV(44), IAV(45), IAV(46), IAV(47), + IAV(48), IAV(49), IAV(50), IAV(51), IAV(52), IAV(53), IAV(54), IAV(55), + IAV(56), IAV(57), IAV(58), IAV(59), IAV(60), IAV(61), IAV(62), IAV(63), + IAV(64), IAV(65), IAV(66), IAV(67), IAV(68), IAV(69), IAV(70), IAV(71), + IAV(72), IAV(73), IAV(74), IAV(75), IAV(76), IAV(77), IAV(78), IAV(79), + IAV(80), IAV(81), IAV(82), IAV(83), IAV(84), IAV(85), IAV(86), IAV(87), + IAV(88), IAV(89), IAV(90), IAV(91), IAV(92), IAV(93), IAV(94), IAV(95), + IAV(96), IAV(97), IAV(98), IAV(99), IAV(100), IAV(101), IAV(102), IAV(103), + IAV(104), IAV(105), IAV(106), IAV(107), IAV(108), IAV(109), IAV(110), IAV(111), + IAV(112), IAV(113), IAV(114), IAV(115), IAV(116), IAV(117), IAV(118), IAV(119), + IAV(120), IAV(121), IAV(122), IAV(123), IAV(124), IAV(125), IAV(126), IAV(127) +}; + +#ifdef CONFIG_NEEDS_MANUAL_RELOC +static void malloc_bin_reloc(void) +{ + mbinptr *p = &av_[2]; + size_t i; + + for (i = 2; i < ARRAY_SIZE(av_); ++i, ++p) + *p = (mbinptr)((ulong)*p + gd->reloc_off); +} +#else +static inline void malloc_bin_reloc(void) {} +#endif + +#ifdef CONFIG_SYS_MALLOC_DEFAULT_TO_INIT +static void malloc_init(void); +#endif + +ulong mem_malloc_start = 0; +ulong mem_malloc_end = 0; +ulong mem_malloc_brk = 0; + +void *sbrk(ptrdiff_t increment) +{ + ulong old = mem_malloc_brk; + ulong new = old + increment; + + /* + * if we are giving memory back make sure we clear it out since + * we set MORECORE_CLEARS to 1 + */ + if (increment < 0) + memset((void *)new, 0, -increment); + + if ((new < mem_malloc_start) || (new > mem_malloc_end)) + return (void *)MORECORE_FAILURE; + + mem_malloc_brk = new; + + return (void *)old; +} + +void mem_malloc_init(ulong start, ulong size) +{ + mem_malloc_start = start; + mem_malloc_end = start + size; + mem_malloc_brk = start; + +#ifdef CONFIG_SYS_MALLOC_DEFAULT_TO_INIT + malloc_init(); +#endif + + debug("using memory %#lx-%#lx for malloc()\n", mem_malloc_start, + mem_malloc_end); +#ifdef CONFIG_SYS_MALLOC_CLEAR_ON_INIT + memset((void *)mem_malloc_start, 0x0, size); +#endif + malloc_bin_reloc(); +} + +/* field-extraction macros */ + +#define first(b) ((b)->fd) +#define last(b) ((b)->bk) + +/* + Indexing into bins +*/ + +#define bin_index(sz) \ +(((((unsigned long)(sz)) >> 9) == 0) ? (((unsigned long)(sz)) >> 3): \ + ((((unsigned long)(sz)) >> 9) <= 4) ? 56 + (((unsigned long)(sz)) >> 6): \ + ((((unsigned long)(sz)) >> 9) <= 20) ? 91 + (((unsigned long)(sz)) >> 9): \ + ((((unsigned long)(sz)) >> 9) <= 84) ? 110 + (((unsigned long)(sz)) >> 12): \ + ((((unsigned long)(sz)) >> 9) <= 340) ? 119 + (((unsigned long)(sz)) >> 15): \ + ((((unsigned long)(sz)) >> 9) <= 1364) ? 124 + (((unsigned long)(sz)) >> 18): \ + 126) +/* + bins for chunks < 512 are all spaced 8 bytes apart, and hold + identically sized chunks. This is exploited in malloc. +*/ + +#define MAX_SMALLBIN 63 +#define MAX_SMALLBIN_SIZE 512 +#define SMALLBIN_WIDTH 8 + +#define smallbin_index(sz) (((unsigned long)(sz)) >> 3) + +/* + Requests are `small' if both the corresponding and the next bin are small +*/ + +#define is_small_request(nb) (nb < MAX_SMALLBIN_SIZE - SMALLBIN_WIDTH) + + + +/* + To help compensate for the large number of bins, a one-level index + structure is used for bin-by-bin searching. `binblocks' is a + one-word bitvector recording whether groups of BINBLOCKWIDTH bins + have any (possibly) non-empty bins, so they can be skipped over + all at once during during traversals. The bits are NOT always + cleared as soon as all bins in a block are empty, but instead only + when all are noticed to be empty during traversal in malloc. +*/ + +#define BINBLOCKWIDTH 4 /* bins per block */ + +#define binblocks_r ((INTERNAL_SIZE_T)av_[1]) /* bitvector of nonempty blocks */ +#define binblocks_w (av_[1]) + +/* bin<->block macros */ + +#define idx2binblock(ix) ((unsigned)1 << (ix / BINBLOCKWIDTH)) +#define mark_binblock(ii) (binblocks_w = (mbinptr)(binblocks_r | idx2binblock(ii))) +#define clear_binblock(ii) (binblocks_w = (mbinptr)(binblocks_r & ~(idx2binblock(ii)))) + + + + + +/* Other static bookkeeping data */ + +/* variables holding tunable values */ + +static unsigned long trim_threshold = DEFAULT_TRIM_THRESHOLD; +static unsigned long top_pad = DEFAULT_TOP_PAD; +static unsigned int n_mmaps_max = DEFAULT_MMAP_MAX; +static unsigned long mmap_threshold = DEFAULT_MMAP_THRESHOLD; + +/* The first value returned from sbrk */ +static char* sbrk_base = (char*)(-1); + +/* The maximum memory obtained from system via sbrk */ +static unsigned long max_sbrked_mem = 0; + +/* The maximum via either sbrk or mmap */ +static unsigned long max_total_mem = 0; + +/* internal working copy of mallinfo */ +static struct mallinfo current_mallinfo = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 }; + +/* The total memory obtained from system via sbrk */ +#define sbrked_mem (current_mallinfo.arena) + +/* Tracking mmaps */ + +#ifdef DEBUG +static unsigned int n_mmaps = 0; +#endif /* DEBUG */ +static unsigned long mmapped_mem = 0; +#if HAVE_MMAP +static unsigned int max_n_mmaps = 0; +static unsigned long max_mmapped_mem = 0; +#endif + +#ifdef CONFIG_SYS_MALLOC_DEFAULT_TO_INIT +static void malloc_init(void) +{ + int i, j; + + debug("bins (av_ array) are at %p\n", (void *)av_); + + av_[0] = NULL; av_[1] = NULL; + for (i = 2, j = 2; i < NAV * 2 + 2; i += 2, j++) { + av_[i] = bin_at(j - 2); + av_[i + 1] = bin_at(j - 2); + + /* Just print the first few bins so that + * we can see there are alright. + */ + if (i < 10) + debug("av_[%d]=%lx av_[%d]=%lx\n", + i, (ulong)av_[i], + i + 1, (ulong)av_[i + 1]); + } + + /* Init the static bookkeeping as well */ + sbrk_base = (char *)(-1); + max_sbrked_mem = 0; + max_total_mem = 0; +#ifdef DEBUG + memset((void *)¤t_mallinfo, 0, sizeof(struct mallinfo)); +#endif +} +#endif + +/* + Debugging support +*/ + +#ifdef DEBUG + + +/* + These routines make a number of assertions about the states + of data structures that should be true at all times. If any + are not true, it's very likely that a user program has somehow + trashed memory. (It's also possible that there is a coding error + in malloc. In which case, please report it!) +*/ + +#if __STD_C +static void do_check_chunk(mchunkptr p) +#else +static void do_check_chunk(p) mchunkptr p; +#endif +{ + INTERNAL_SIZE_T sz = p->size & ~PREV_INUSE; + + /* No checkable chunk is mmapped */ + assert(!chunk_is_mmapped(p)); + + /* Check for legal address ... */ + assert((char*)p >= sbrk_base); + if (p != top) + assert((char*)p + sz <= (char*)top); + else + assert((char*)p + sz <= sbrk_base + sbrked_mem); + +} + + +#if __STD_C +static void do_check_free_chunk(mchunkptr p) +#else +static void do_check_free_chunk(p) mchunkptr p; +#endif +{ + INTERNAL_SIZE_T sz = p->size & ~PREV_INUSE; + mchunkptr next = chunk_at_offset(p, sz); + + do_check_chunk(p); + + /* Check whether it claims to be free ... */ + assert(!inuse(p)); + + /* Unless a special marker, must have OK fields */ + if ((long)sz >= (long)MINSIZE) + { + assert((sz & MALLOC_ALIGN_MASK) == 0); + assert(aligned_OK(chunk2mem(p))); + /* ... matching footer field */ + assert(next->prev_size == sz); + /* ... and is fully consolidated */ + assert(prev_inuse(p)); + assert (next == top || inuse(next)); + + /* ... and has minimally sane links */ + assert(p->fd->bk == p); + assert(p->bk->fd == p); + } + else /* markers are always of size SIZE_SZ */ + assert(sz == SIZE_SZ); +} + +#if __STD_C +static void do_check_inuse_chunk(mchunkptr p) +#else +static void do_check_inuse_chunk(p) mchunkptr p; +#endif +{ + mchunkptr next = next_chunk(p); + do_check_chunk(p); + + /* Check whether it claims to be in use ... */ + assert(inuse(p)); + + /* ... and is surrounded by OK chunks. + Since more things can be checked with free chunks than inuse ones, + if an inuse chunk borders them and debug is on, it's worth doing them. + */ + if (!prev_inuse(p)) + { + mchunkptr prv = prev_chunk(p); + assert(next_chunk(prv) == p); + do_check_free_chunk(prv); + } + if (next == top) + { + assert(prev_inuse(next)); + assert(chunksize(next) >= MINSIZE); + } + else if (!inuse(next)) + do_check_free_chunk(next); + +} + +#if __STD_C +static void do_check_malloced_chunk(mchunkptr p, INTERNAL_SIZE_T s) +#else +static void do_check_malloced_chunk(p, s) mchunkptr p; INTERNAL_SIZE_T s; +#endif +{ + INTERNAL_SIZE_T sz = p->size & ~PREV_INUSE; + long room = sz - s; + + do_check_inuse_chunk(p); + + /* Legal size ... */ + assert((long)sz >= (long)MINSIZE); + assert((sz & MALLOC_ALIGN_MASK) == 0); + assert(room >= 0); + assert(room < (long)MINSIZE); + + /* ... and alignment */ + assert(aligned_OK(chunk2mem(p))); + + + /* ... and was allocated at front of an available chunk */ + assert(prev_inuse(p)); + +} + + +#define check_free_chunk(P) do_check_free_chunk(P) +#define check_inuse_chunk(P) do_check_inuse_chunk(P) +#define check_chunk(P) do_check_chunk(P) +#define check_malloced_chunk(P,N) do_check_malloced_chunk(P,N) +#else +#define check_free_chunk(P) +#define check_inuse_chunk(P) +#define check_chunk(P) +#define check_malloced_chunk(P,N) +#endif + + + +/* + Macro-based internal utilities +*/ + + +/* + Linking chunks in bin lists. + Call these only with variables, not arbitrary expressions, as arguments. +*/ + +/* + Place chunk p of size s in its bin, in size order, + putting it ahead of others of same size. +*/ + + +#define frontlink(P, S, IDX, BK, FD) \ +{ \ + if (S < MAX_SMALLBIN_SIZE) \ + { \ + IDX = smallbin_index(S); \ + mark_binblock(IDX); \ + BK = bin_at(IDX); \ + FD = BK->fd; \ + P->bk = BK; \ + P->fd = FD; \ + FD->bk = BK->fd = P; \ + } \ + else \ + { \ + IDX = bin_index(S); \ + BK = bin_at(IDX); \ + FD = BK->fd; \ + if (FD == BK) mark_binblock(IDX); \ + else \ + { \ + while (FD != BK && S < chunksize(FD)) FD = FD->fd; \ + BK = FD->bk; \ + } \ + P->bk = BK; \ + P->fd = FD; \ + FD->bk = BK->fd = P; \ + } \ +} + + +/* take a chunk off a list */ + +#define unlink(P, BK, FD) \ +{ \ + BK = P->bk; \ + FD = P->fd; \ + FD->bk = BK; \ + BK->fd = FD; \ +} \ + +/* Place p as the last remainder */ + +#define link_last_remainder(P) \ +{ \ + last_remainder->fd = last_remainder->bk = P; \ + P->fd = P->bk = last_remainder; \ +} + +/* Clear the last_remainder bin */ + +#define clear_last_remainder \ + (last_remainder->fd = last_remainder->bk = last_remainder) + + + + + +/* Routines dealing with mmap(). */ + +#if HAVE_MMAP + +#if __STD_C +static mchunkptr mmap_chunk(size_t size) +#else +static mchunkptr mmap_chunk(size) size_t size; +#endif +{ + size_t page_mask = malloc_getpagesize - 1; + mchunkptr p; + +#ifndef MAP_ANONYMOUS + static int fd = -1; +#endif + + if(n_mmaps >= n_mmaps_max) return 0; /* too many regions */ + + /* For mmapped chunks, the overhead is one SIZE_SZ unit larger, because + * there is no following chunk whose prev_size field could be used. + */ + size = (size + SIZE_SZ + page_mask) & ~page_mask; + +#ifdef MAP_ANONYMOUS + p = (mchunkptr)mmap(0, size, PROT_READ|PROT_WRITE, + MAP_PRIVATE|MAP_ANONYMOUS, -1, 0); +#else /* !MAP_ANONYMOUS */ + if (fd < 0) + { + fd = open("/dev/zero", O_RDWR); + if(fd < 0) return 0; + } + p = (mchunkptr)mmap(0, size, PROT_READ|PROT_WRITE, MAP_PRIVATE, fd, 0); +#endif + + if(p == (mchunkptr)-1) return 0; + + n_mmaps++; + if (n_mmaps > max_n_mmaps) max_n_mmaps = n_mmaps; + + /* We demand that eight bytes into a page must be 8-byte aligned. */ + assert(aligned_OK(chunk2mem(p))); + + /* The offset to the start of the mmapped region is stored + * in the prev_size field of the chunk; normally it is zero, + * but that can be changed in memalign(). + */ + p->prev_size = 0; + set_head(p, size|IS_MMAPPED); + + mmapped_mem += size; + if ((unsigned long)mmapped_mem > (unsigned long)max_mmapped_mem) + max_mmapped_mem = mmapped_mem; + if ((unsigned long)(mmapped_mem + sbrked_mem) > (unsigned long)max_total_mem) + max_total_mem = mmapped_mem + sbrked_mem; + return p; +} + +#if __STD_C +static void munmap_chunk(mchunkptr p) +#else +static void munmap_chunk(p) mchunkptr p; +#endif +{ + INTERNAL_SIZE_T size = chunksize(p); + int ret; + + assert (chunk_is_mmapped(p)); + assert(! ((char*)p >= sbrk_base && (char*)p < sbrk_base + sbrked_mem)); + assert((n_mmaps > 0)); + assert(((p->prev_size + size) & (malloc_getpagesize-1)) == 0); + + n_mmaps--; + mmapped_mem -= (size + p->prev_size); + + ret = munmap((char *)p - p->prev_size, size + p->prev_size); + + /* munmap returns non-zero on failure */ + assert(ret == 0); +} + +#if HAVE_MREMAP + +#if __STD_C +static mchunkptr mremap_chunk(mchunkptr p, size_t new_size) +#else +static mchunkptr mremap_chunk(p, new_size) mchunkptr p; size_t new_size; +#endif +{ + size_t page_mask = malloc_getpagesize - 1; + INTERNAL_SIZE_T offset = p->prev_size; + INTERNAL_SIZE_T size = chunksize(p); + char *cp; + + assert (chunk_is_mmapped(p)); + assert(! ((char*)p >= sbrk_base && (char*)p < sbrk_base + sbrked_mem)); + assert((n_mmaps > 0)); + assert(((size + offset) & (malloc_getpagesize-1)) == 0); + + /* Note the extra SIZE_SZ overhead as in mmap_chunk(). */ + new_size = (new_size + offset + SIZE_SZ + page_mask) & ~page_mask; + + cp = (char *)mremap((char *)p - offset, size + offset, new_size, 1); + + if (cp == (char *)-1) return 0; + + p = (mchunkptr)(cp + offset); + + assert(aligned_OK(chunk2mem(p))); + + assert((p->prev_size == offset)); + set_head(p, (new_size - offset)|IS_MMAPPED); + + mmapped_mem -= size + offset; + mmapped_mem += new_size; + if ((unsigned long)mmapped_mem > (unsigned long)max_mmapped_mem) + max_mmapped_mem = mmapped_mem; + if ((unsigned long)(mmapped_mem + sbrked_mem) > (unsigned long)max_total_mem) + max_total_mem = mmapped_mem + sbrked_mem; + return p; +} + +#endif /* HAVE_MREMAP */ + +#endif /* HAVE_MMAP */ + +/* + Extend the top-most chunk by obtaining memory from system. + Main interface to sbrk (but see also malloc_trim). +*/ + +#if __STD_C +static void malloc_extend_top(INTERNAL_SIZE_T nb) +#else +static void malloc_extend_top(nb) INTERNAL_SIZE_T nb; +#endif +{ + char* brk; /* return value from sbrk */ + INTERNAL_SIZE_T front_misalign; /* unusable bytes at front of sbrked space */ + INTERNAL_SIZE_T correction; /* bytes for 2nd sbrk call */ + char* new_brk; /* return of 2nd sbrk call */ + INTERNAL_SIZE_T top_size; /* new size of top chunk */ + + mchunkptr old_top = top; /* Record state of old top */ + INTERNAL_SIZE_T old_top_size = chunksize(old_top); + char* old_end = (char*)(chunk_at_offset(old_top, old_top_size)); + + /* Pad request with top_pad plus minimal overhead */ + + INTERNAL_SIZE_T sbrk_size = nb + top_pad + MINSIZE; + unsigned long pagesz = malloc_getpagesize; + + /* If not the first time through, round to preserve page boundary */ + /* Otherwise, we need to correct to a page size below anyway. */ + /* (We also correct below if an intervening foreign sbrk call.) */ + + if (sbrk_base != (char*)(-1)) + sbrk_size = (sbrk_size + (pagesz - 1)) & ~(pagesz - 1); + + brk = (char*)(MORECORE (sbrk_size)); + + /* Fail if sbrk failed or if a foreign sbrk call killed our space */ + if (brk == (char*)(MORECORE_FAILURE) || + (brk < old_end && old_top != initial_top)) + return; + + sbrked_mem += sbrk_size; + + if (brk == old_end) /* can just add bytes to current top */ + { + top_size = sbrk_size + old_top_size; + set_head(top, top_size | PREV_INUSE); + } + else + { + if (sbrk_base == (char*)(-1)) /* First time through. Record base */ + sbrk_base = brk; + else /* Someone else called sbrk(). Count those bytes as sbrked_mem. */ + sbrked_mem += brk - (char*)old_end; + + /* Guarantee alignment of first new chunk made from this space */ + front_misalign = (unsigned long)chunk2mem(brk) & MALLOC_ALIGN_MASK; + if (front_misalign > 0) + { + correction = (MALLOC_ALIGNMENT) - front_misalign; + brk += correction; + } + else + correction = 0; + + /* Guarantee the next brk will be at a page boundary */ + + correction += ((((unsigned long)(brk + sbrk_size))+(pagesz-1)) & + ~(pagesz - 1)) - ((unsigned long)(brk + sbrk_size)); + + /* Allocate correction */ + new_brk = (char*)(MORECORE (correction)); + if (new_brk == (char*)(MORECORE_FAILURE)) return; + + sbrked_mem += correction; + + top = (mchunkptr)brk; + top_size = new_brk - brk + correction; + set_head(top, top_size | PREV_INUSE); + + if (old_top != initial_top) + { + + /* There must have been an intervening foreign sbrk call. */ + /* A double fencepost is necessary to prevent consolidation */ + + /* If not enough space to do this, then user did something very wrong */ + if (old_top_size < MINSIZE) + { + set_head(top, PREV_INUSE); /* will force null return from malloc */ + return; + } + + /* Also keep size a multiple of MALLOC_ALIGNMENT */ + old_top_size = (old_top_size - 3*SIZE_SZ) & ~MALLOC_ALIGN_MASK; + set_head_size(old_top, old_top_size); + chunk_at_offset(old_top, old_top_size )->size = + SIZE_SZ|PREV_INUSE; + chunk_at_offset(old_top, old_top_size + SIZE_SZ)->size = + SIZE_SZ|PREV_INUSE; + /* If possible, release the rest. */ + if (old_top_size >= MINSIZE) + fREe(chunk2mem(old_top)); + } + } + + if ((unsigned long)sbrked_mem > (unsigned long)max_sbrked_mem) + max_sbrked_mem = sbrked_mem; + if ((unsigned long)(mmapped_mem + sbrked_mem) > (unsigned long)max_total_mem) + max_total_mem = mmapped_mem + sbrked_mem; + + /* We always land on a page boundary */ + assert(((unsigned long)((char*)top + top_size) & (pagesz - 1)) == 0); +} + + + + +/* Main public routines */ + + +/* + Malloc Algorthim: + + The requested size is first converted into a usable form, `nb'. + This currently means to add 4 bytes overhead plus possibly more to + obtain 8-byte alignment and/or to obtain a size of at least + MINSIZE (currently 16 bytes), the smallest allocatable size. + (All fits are considered `exact' if they are within MINSIZE bytes.) + + From there, the first successful of the following steps is taken: + + 1. The bin corresponding to the request size is scanned, and if + a chunk of exactly the right size is found, it is taken. + + 2. The most recently remaindered chunk is used if it is big + enough. This is a form of (roving) first fit, used only in + the absence of exact fits. Runs of consecutive requests use + the remainder of the chunk used for the previous such request + whenever possible. This limited use of a first-fit style + allocation strategy tends to give contiguous chunks + coextensive lifetimes, which improves locality and can reduce + fragmentation in the long run. + + 3. Other bins are scanned in increasing size order, using a + chunk big enough to fulfill the request, and splitting off + any remainder. 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. + + 4. If large enough, the chunk bordering the end of memory + (`top') is split off. (This use of `top' is in accord with + the best-fit search rule. In effect, `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). + + 5. If the request size meets the mmap threshold and the + system supports mmap, and there are few enough currently + allocated mmapped regions, and a call to mmap succeeds, + the request is allocated via direct memory mapping. + + 6. Otherwise, the top of memory is extended by + obtaining more space from the system (normally using sbrk, + but definable to anything else via the MORECORE macro). + Memory is gathered from the system (in system page-sized + units) in a way that allows chunks obtained across different + sbrk calls to be consolidated, but does not require + contiguous memory. Thus, it should be safe to intersperse + mallocs with other sbrk calls. + + + All allocations are made from the the `lowest' part of any found + chunk. (The implementation invariant is that prev_inuse is + always true of any allocated chunk; i.e., that each allocated + chunk borders either a previously allocated and still in-use chunk, + or the base of its memory arena.) + +*/ + +#if __STD_C +Void_t* mALLOc(size_t bytes) +#else +Void_t* mALLOc(bytes) size_t bytes; +#endif +{ + mchunkptr victim; /* inspected/selected chunk */ + INTERNAL_SIZE_T victim_size; /* its size */ + int idx; /* index for bin traversal */ + mbinptr bin; /* associated bin */ + mchunkptr remainder; /* remainder from a split */ + long remainder_size; /* its size */ + int remainder_index; /* its bin index */ + unsigned long block; /* block traverser bit */ + int startidx; /* first bin of a traversed block */ + mchunkptr fwd; /* misc temp for linking */ + mchunkptr bck; /* misc temp for linking */ + mbinptr q; /* misc temp */ + + INTERNAL_SIZE_T nb; + +#if CONFIG_VAL(SYS_MALLOC_F_LEN) + if (!(gd->flags & GD_FLG_FULL_MALLOC_INIT)) + return malloc_simple(bytes); +#endif + + /* check if mem_malloc_init() was run */ + if ((mem_malloc_start == 0) && (mem_malloc_end == 0)) { + /* not initialized yet */ + return NULL; + } + + if ((long)bytes < 0) return NULL; + + nb = request2size(bytes); /* padded request size; */ + + /* Check for exact match in a bin */ + + if (is_small_request(nb)) /* Faster version for small requests */ + { + idx = smallbin_index(nb); + + /* No traversal or size check necessary for small bins. */ + + q = bin_at(idx); + victim = last(q); + + /* Also scan the next one, since it would have a remainder < MINSIZE */ + if (victim == q) + { + q = next_bin(q); + victim = last(q); + } + if (victim != q) + { + victim_size = chunksize(victim); + unlink(victim, bck, fwd); + set_inuse_bit_at_offset(victim, victim_size); + check_malloced_chunk(victim, nb); + return chunk2mem(victim); + } + + idx += 2; /* Set for bin scan below. We've already scanned 2 bins. */ + + } + else + { + idx = bin_index(nb); + bin = bin_at(idx); + + for (victim = last(bin); victim != bin; victim = victim->bk) + { + victim_size = chunksize(victim); + remainder_size = victim_size - nb; + + if (remainder_size >= (long)MINSIZE) /* too big */ + { + --idx; /* adjust to rescan below after checking last remainder */ + break; + } + + else if (remainder_size >= 0) /* exact fit */ + { + unlink(victim, bck, fwd); + set_inuse_bit_at_offset(victim, victim_size); + check_malloced_chunk(victim, nb); + return chunk2mem(victim); + } + } + + ++idx; + + } + + /* Try to use the last split-off remainder */ + + if ( (victim = last_remainder->fd) != last_remainder) + { + victim_size = chunksize(victim); + remainder_size = victim_size - nb; + + if (remainder_size >= (long)MINSIZE) /* re-split */ + { + remainder = chunk_at_offset(victim, nb); + set_head(victim, nb | PREV_INUSE); + link_last_remainder(remainder); + set_head(remainder, remainder_size | PREV_INUSE); + set_foot(remainder, remainder_size); + check_malloced_chunk(victim, nb); + return chunk2mem(victim); + } + + clear_last_remainder; + + if (remainder_size >= 0) /* exhaust */ + { + set_inuse_bit_at_offset(victim, victim_size); + check_malloced_chunk(victim, nb); + return chunk2mem(victim); + } + + /* Else place in bin */ + + frontlink(victim, victim_size, remainder_index, bck, fwd); + } + + /* + If there are any possibly nonempty big-enough blocks, + search for best fitting chunk by scanning bins in blockwidth units. + */ + + if ( (block = idx2binblock(idx)) <= binblocks_r) + { + + /* Get to the first marked block */ + + if ( (block & binblocks_r) == 0) + { + /* force to an even block boundary */ + idx = (idx & ~(BINBLOCKWIDTH - 1)) + BINBLOCKWIDTH; + block <<= 1; + while ((block & binblocks_r) == 0) + { + idx += BINBLOCKWIDTH; + block <<= 1; + } + } + + /* For each possibly nonempty block ... */ + for (;;) + { + startidx = idx; /* (track incomplete blocks) */ + q = bin = bin_at(idx); + + /* For each bin in this block ... */ + do + { + /* Find and use first big enough chunk ... */ + + for (victim = last(bin); victim != bin; victim = victim->bk) + { + victim_size = chunksize(victim); + remainder_size = victim_size - nb; + + if (remainder_size >= (long)MINSIZE) /* split */ + { + remainder = chunk_at_offset(victim, nb); + set_head(victim, nb | PREV_INUSE); + unlink(victim, bck, fwd); + link_last_remainder(remainder); + set_head(remainder, remainder_size | PREV_INUSE); + set_foot(remainder, remainder_size); + check_malloced_chunk(victim, nb); + return chunk2mem(victim); + } + + else if (remainder_size >= 0) /* take */ + { + set_inuse_bit_at_offset(victim, victim_size); + unlink(victim, bck, fwd); + check_malloced_chunk(victim, nb); + return chunk2mem(victim); + } + + } + + bin = next_bin(bin); + + } while ((++idx & (BINBLOCKWIDTH - 1)) != 0); + + /* Clear out the block bit. */ + + do /* Possibly backtrack to try to clear a partial block */ + { + if ((startidx & (BINBLOCKWIDTH - 1)) == 0) + { + av_[1] = (mbinptr)(binblocks_r & ~block); + break; + } + --startidx; + q = prev_bin(q); + } while (first(q) == q); + + /* Get to the next possibly nonempty block */ + + if ( (block <<= 1) <= binblocks_r && (block != 0) ) + { + while ((block & binblocks_r) == 0) + { + idx += BINBLOCKWIDTH; + block <<= 1; + } + } + else + break; + } + } + + + /* Try to use top chunk */ + + /* Require that there be a remainder, ensuring top always exists */ + if ( (remainder_size = chunksize(top) - nb) < (long)MINSIZE) + { + +#if HAVE_MMAP + /* If big and would otherwise need to extend, try to use mmap instead */ + if ((unsigned long)nb >= (unsigned long)mmap_threshold && + (victim = mmap_chunk(nb))) + return chunk2mem(victim); +#endif + + /* Try to extend */ + malloc_extend_top(nb); + if ( (remainder_size = chunksize(top) - nb) < (long)MINSIZE) + return NULL; /* propagate failure */ + } + + victim = top; + set_head(victim, nb | PREV_INUSE); + top = chunk_at_offset(victim, nb); + set_head(top, remainder_size | PREV_INUSE); + check_malloced_chunk(victim, nb); + return chunk2mem(victim); + +} + + + + +/* + + free() algorithm : + + cases: + + 1. free(0) has no effect. + + 2. If the chunk was allocated via mmap, it is release via munmap(). + + 3. If a returned chunk borders the current high end of memory, + it is consolidated into the top, and if the total unused + topmost memory exceeds the trim threshold, malloc_trim is + called. + + 4. Other chunks are consolidated as they arrive, and + placed in corresponding bins. (This includes the case of + consolidating with the current `last_remainder'). + +*/ + + +#if __STD_C +void fREe(Void_t* mem) +#else +void fREe(mem) Void_t* mem; +#endif +{ + mchunkptr p; /* chunk corresponding to mem */ + INTERNAL_SIZE_T hd; /* its head field */ + INTERNAL_SIZE_T sz; /* its size */ + int idx; /* its bin index */ + mchunkptr next; /* next contiguous chunk */ + INTERNAL_SIZE_T nextsz; /* its size */ + INTERNAL_SIZE_T prevsz; /* size of previous contiguous chunk */ + mchunkptr bck; /* misc temp for linking */ + mchunkptr fwd; /* misc temp for linking */ + int islr; /* track whether merging with last_remainder */ + +#if CONFIG_VAL(SYS_MALLOC_F_LEN) + /* free() is a no-op - all the memory will be freed on relocation */ + if (!(gd->flags & GD_FLG_FULL_MALLOC_INIT)) + return; +#endif + + if (mem == NULL) /* free(0) has no effect */ + return; + + p = mem2chunk(mem); + hd = p->size; + +#if HAVE_MMAP + if (hd & IS_MMAPPED) /* release mmapped memory. */ + { + munmap_chunk(p); + return; + } +#endif + + check_inuse_chunk(p); + + sz = hd & ~PREV_INUSE; + next = chunk_at_offset(p, sz); + nextsz = chunksize(next); + + if (next == top) /* merge with top */ + { + sz += nextsz; + + if (!(hd & PREV_INUSE)) /* consolidate backward */ + { + prevsz = p->prev_size; + p = chunk_at_offset(p, -((long) prevsz)); + sz += prevsz; + unlink(p, bck, fwd); + } + + set_head(p, sz | PREV_INUSE); + top = p; + if ((unsigned long)(sz) >= (unsigned long)trim_threshold) + malloc_trim(top_pad); + return; + } + + set_head(next, nextsz); /* clear inuse bit */ + + islr = 0; + + if (!(hd & PREV_INUSE)) /* consolidate backward */ + { + prevsz = p->prev_size; + p = chunk_at_offset(p, -((long) prevsz)); + sz += prevsz; + + if (p->fd == last_remainder) /* keep as last_remainder */ + islr = 1; + else + unlink(p, bck, fwd); + } + + if (!(inuse_bit_at_offset(next, nextsz))) /* consolidate forward */ + { + sz += nextsz; + + if (!islr && next->fd == last_remainder) /* re-insert last_remainder */ + { + islr = 1; + link_last_remainder(p); + } + else + unlink(next, bck, fwd); + } + + + set_head(p, sz | PREV_INUSE); + set_foot(p, sz); + if (!islr) + frontlink(p, sz, idx, bck, fwd); +} + + + + + +/* + + Realloc algorithm: + + Chunks that were obtained via mmap cannot be extended or shrunk + unless HAVE_MREMAP is defined, in which case mremap is used. + Otherwise, if their reallocation is for additional space, they are + copied. If for less, they are just left alone. + + Otherwise, if the reallocation is for additional space, and the + chunk can be extended, it is, else a malloc-copy-free sequence is + taken. There are several different ways that a chunk could be + extended. All are tried: + + * Extending forward into following adjacent free chunk. + * Shifting backwards, joining preceding adjacent space + * Both shifting backwards and extending forward. + * Extending into newly sbrked space + + Unless the #define REALLOC_ZERO_BYTES_FREES is set, realloc with a + size argument of zero (re)allocates a minimum-sized chunk. + + If the reallocation is for less space, and the new request is for + a `small' (<512 bytes) size, then the newly unused space is lopped + off and freed. + + The old unix realloc convention of allowing the last-free'd chunk + to be used as an argument to realloc is no longer supported. + I don't know of any programs still relying on this feature, + and allowing it would also allow too many other incorrect + usages of realloc to be sensible. + + +*/ + + +#if __STD_C +Void_t* rEALLOc(Void_t* oldmem, size_t bytes) +#else +Void_t* rEALLOc(oldmem, bytes) Void_t* oldmem; size_t bytes; +#endif +{ + INTERNAL_SIZE_T nb; /* padded request size */ + + mchunkptr oldp; /* chunk corresponding to oldmem */ + INTERNAL_SIZE_T oldsize; /* its size */ + + mchunkptr newp; /* chunk to return */ + INTERNAL_SIZE_T newsize; /* its size */ + Void_t* newmem; /* corresponding user mem */ + + mchunkptr next; /* next contiguous chunk after oldp */ + INTERNAL_SIZE_T nextsize; /* its size */ + + mchunkptr prev; /* previous contiguous chunk before oldp */ + INTERNAL_SIZE_T prevsize; /* its size */ + + mchunkptr remainder; /* holds split off extra space from newp */ + INTERNAL_SIZE_T remainder_size; /* its size */ + + mchunkptr bck; /* misc temp for linking */ + mchunkptr fwd; /* misc temp for linking */ + +#ifdef REALLOC_ZERO_BYTES_FREES + if (!bytes) { + fREe(oldmem); + return NULL; + } +#endif + + if ((long)bytes < 0) return NULL; + + /* realloc of null is supposed to be same as malloc */ + if (oldmem == NULL) return mALLOc(bytes); + +#if CONFIG_VAL(SYS_MALLOC_F_LEN) + if (!(gd->flags & GD_FLG_FULL_MALLOC_INIT)) { + /* This is harder to support and should not be needed */ + panic("pre-reloc realloc() is not supported"); + } +#endif + + newp = oldp = mem2chunk(oldmem); + newsize = oldsize = chunksize(oldp); + + + nb = request2size(bytes); + +#if HAVE_MMAP + if (chunk_is_mmapped(oldp)) + { +#if HAVE_MREMAP + newp = mremap_chunk(oldp, nb); + if(newp) return chunk2mem(newp); +#endif + /* Note the extra SIZE_SZ overhead. */ + if(oldsize - SIZE_SZ >= nb) return oldmem; /* do nothing */ + /* Must alloc, copy, free. */ + newmem = mALLOc(bytes); + if (!newmem) + return NULL; /* propagate failure */ + MALLOC_COPY(newmem, oldmem, oldsize - 2*SIZE_SZ); + munmap_chunk(oldp); + return newmem; + } +#endif + + check_inuse_chunk(oldp); + + if ((long)(oldsize) < (long)(nb)) + { + + /* Try expanding forward */ + + next = chunk_at_offset(oldp, oldsize); + if (next == top || !inuse(next)) + { + nextsize = chunksize(next); + + /* Forward into top only if a remainder */ + if (next == top) + { + if ((long)(nextsize + newsize) >= (long)(nb + MINSIZE)) + { + newsize += nextsize; + top = chunk_at_offset(oldp, nb); + set_head(top, (newsize - nb) | PREV_INUSE); + set_head_size(oldp, nb); + return chunk2mem(oldp); + } + } + + /* Forward into next chunk */ + else if (((long)(nextsize + newsize) >= (long)(nb))) + { + unlink(next, bck, fwd); + newsize += nextsize; + goto split; + } + } + else + { + next = NULL; + nextsize = 0; + } + + /* Try shifting backwards. */ + + if (!prev_inuse(oldp)) + { + prev = prev_chunk(oldp); + prevsize = chunksize(prev); + + /* try forward + backward first to save a later consolidation */ + + if (next != NULL) + { + /* into top */ + if (next == top) + { + if ((long)(nextsize + prevsize + newsize) >= (long)(nb + MINSIZE)) + { + unlink(prev, bck, fwd); + newp = prev; + newsize += prevsize + nextsize; + newmem = chunk2mem(newp); + MALLOC_COPY(newmem, oldmem, oldsize - SIZE_SZ); + top = chunk_at_offset(newp, nb); + set_head(top, (newsize - nb) | PREV_INUSE); + set_head_size(newp, nb); + return newmem; + } + } + + /* into next chunk */ + else if (((long)(nextsize + prevsize + newsize) >= (long)(nb))) + { + unlink(next, bck, fwd); + unlink(prev, bck, fwd); + newp = prev; + newsize += nextsize + prevsize; + newmem = chunk2mem(newp); + MALLOC_COPY(newmem, oldmem, oldsize - SIZE_SZ); + goto split; + } + } + + /* backward only */ + if (prev != NULL && (long)(prevsize + newsize) >= (long)nb) + { + unlink(prev, bck, fwd); + newp = prev; + newsize += prevsize; + newmem = chunk2mem(newp); + MALLOC_COPY(newmem, oldmem, oldsize - SIZE_SZ); + goto split; + } + } + + /* Must allocate */ + + newmem = mALLOc (bytes); + + if (newmem == NULL) /* propagate failure */ + return NULL; + + /* Avoid copy if newp is next chunk after oldp. */ + /* (This can only happen when new chunk is sbrk'ed.) */ + + if ( (newp = mem2chunk(newmem)) == next_chunk(oldp)) + { + newsize += chunksize(newp); + newp = oldp; + goto split; + } + + /* Otherwise copy, free, and exit */ + MALLOC_COPY(newmem, oldmem, oldsize - SIZE_SZ); + fREe(oldmem); + return newmem; + } + + + split: /* split off extra room in old or expanded chunk */ + + if (newsize - nb >= MINSIZE) /* split off remainder */ + { + remainder = chunk_at_offset(newp, nb); + remainder_size = newsize - nb; + set_head_size(newp, nb); + set_head(remainder, remainder_size | PREV_INUSE); + set_inuse_bit_at_offset(remainder, remainder_size); + fREe(chunk2mem(remainder)); /* let free() deal with it */ + } + else + { + set_head_size(newp, newsize); + set_inuse_bit_at_offset(newp, newsize); + } + + check_inuse_chunk(newp); + return chunk2mem(newp); +} + + + + +/* + + memalign algorithm: + + memalign requests more than enough space from malloc, finds a spot + within that chunk that meets the alignment request, and then + possibly frees the leading and trailing space. + + The alignment argument must be a power of two. This property is not + checked by memalign, so misuse may result in random runtime errors. + + 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* mEMALIGn(size_t alignment, size_t bytes) +#else +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 */ + mchunkptr p; /* corresponding chunk */ + char* brk; /* alignment point within p */ + mchunkptr newp; /* chunk to return */ + INTERNAL_SIZE_T newsize; /* its size */ + INTERNAL_SIZE_T leadsize; /* leading space befor alignment point */ + mchunkptr remainder; /* spare room at end to split off */ + long remainder_size; /* its size */ + + if ((long)bytes < 0) return NULL; + +#if CONFIG_VAL(SYS_MALLOC_F_LEN) + if (!(gd->flags & GD_FLG_FULL_MALLOC_INIT)) { + return memalign_simple(alignment, bytes); + } +#endif + + /* If need less alignment than we give anyway, just relay to malloc */ + + if (alignment <= MALLOC_ALIGNMENT) return mALLOc(bytes); + + /* Otherwise, ensure that it is at least a minimum chunk size */ + + if (alignment < MINSIZE) alignment = MINSIZE; + + /* Call malloc with worst case padding to hit alignment. */ + + nb = request2size(bytes); + m = (char*)(mALLOc(nb + alignment + MINSIZE)); + + /* + * The attempt to over-allocate (with a size large enough to guarantee the + * ability to find an aligned region within allocated memory) failed. + * + * Try again, this time only allocating exactly the size the user wants. If + * the allocation now succeeds and just happens to be aligned, we can still + * fulfill the user's request. + */ + if (m == NULL) { + size_t extra, extra2; + /* + * Use bytes not nb, since mALLOc internally calls request2size too, and + * each call increases the size to allocate, to account for the header. + */ + m = (char*)(mALLOc(bytes)); + /* Aligned -> return it */ + if ((((unsigned long)(m)) % alignment) == 0) + return m; + /* + * Otherwise, try again, requesting enough extra space to be able to + * acquire alignment. + */ + fREe(m); + /* Add in extra bytes to match misalignment of unexpanded allocation */ + extra = alignment - (((unsigned long)(m)) % alignment); + m = (char*)(mALLOc(bytes + extra)); + /* + * m might not be the same as before. Validate that the previous value of + * extra still works for the current value of m. + * If (!m), extra2=alignment so + */ + if (m) { + extra2 = alignment - (((unsigned long)(m)) % alignment); + if (extra2 > extra) { + fREe(m); + m = NULL; + } + } + /* Fall through to original NULL check and chunk splitting logic */ + } + + if (m == NULL) return NULL; /* propagate failure */ + + p = mem2chunk(m); + + if ((((unsigned long)(m)) % alignment) == 0) /* aligned */ + { +#if HAVE_MMAP + if(chunk_is_mmapped(p)) + return chunk2mem(p); /* nothing more to do */ +#endif + } + else /* 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*)mem2chunk(((unsigned long)(m + alignment - 1)) & -((signed) alignment)); + if ((long)(brk - (char*)(p)) < MINSIZE) brk = brk + alignment; + + newp = (mchunkptr)brk; + leadsize = brk - (char*)(p); + newsize = chunksize(p) - leadsize; + +#if HAVE_MMAP + if(chunk_is_mmapped(p)) + { + newp->prev_size = p->prev_size + leadsize; + set_head(newp, newsize|IS_MMAPPED); + return chunk2mem(newp); + } +#endif + + /* give back leader, use the rest */ + + set_head(newp, newsize | PREV_INUSE); + set_inuse_bit_at_offset(newp, newsize); + set_head_size(p, leadsize); + fREe(chunk2mem(p)); + p = newp; + + assert (newsize >= nb && (((unsigned long)(chunk2mem(p))) % alignment) == 0); + } + + /* Also give back spare room at the end */ + + remainder_size = chunksize(p) - nb; + + if (remainder_size >= (long)MINSIZE) + { + remainder = chunk_at_offset(p, nb); + set_head(remainder, remainder_size | PREV_INUSE); + set_head_size(p, nb); + fREe(chunk2mem(remainder)); + } + + check_inuse_chunk(p); + return chunk2mem(p); + +} + + + + +/* + valloc just invokes memalign with alignment argument equal + to the page size of the system (or as near to this as can + be figured out from all the includes/defines above.) +*/ + +#if __STD_C +Void_t* vALLOc(size_t bytes) +#else +Void_t* vALLOc(bytes) size_t bytes; +#endif +{ + return mEMALIGn (malloc_getpagesize, bytes); +} + +/* + pvalloc just invokes valloc for the nearest pagesize + that will accommodate request +*/ + + +#if __STD_C +Void_t* pvALLOc(size_t bytes) +#else +Void_t* pvALLOc(bytes) size_t bytes; +#endif +{ + size_t pagesize = malloc_getpagesize; + return mEMALIGn (pagesize, (bytes + pagesize - 1) & ~(pagesize - 1)); +} + +/* + + calloc calls malloc, then zeroes out the allocated chunk. + +*/ + +#if __STD_C +Void_t* cALLOc(size_t n, size_t elem_size) +#else +Void_t* cALLOc(n, elem_size) size_t n; size_t elem_size; +#endif +{ + mchunkptr p; + INTERNAL_SIZE_T csz; + + INTERNAL_SIZE_T sz = n * elem_size; + + + /* check if expand_top called, in which case don't need to clear */ +#ifdef CONFIG_SYS_MALLOC_CLEAR_ON_INIT +#if MORECORE_CLEARS + mchunkptr oldtop = top; + INTERNAL_SIZE_T oldtopsize = chunksize(top); +#endif +#endif + Void_t* mem = mALLOc (sz); + + if ((long)n < 0) return NULL; + + if (mem == NULL) + return NULL; + else + { +#if CONFIG_VAL(SYS_MALLOC_F_LEN) + if (!(gd->flags & GD_FLG_FULL_MALLOC_INIT)) { + memset(mem, 0, sz); + return mem; + } +#endif + p = mem2chunk(mem); + + /* Two optional cases in which clearing not necessary */ + + +#if HAVE_MMAP + if (chunk_is_mmapped(p)) return mem; +#endif + + csz = chunksize(p); + +#ifdef CONFIG_SYS_MALLOC_CLEAR_ON_INIT +#if MORECORE_CLEARS + if (p == oldtop && csz > oldtopsize) + { + /* clear only the bytes from non-freshly-sbrked memory */ + csz = oldtopsize; + } +#endif +#endif + + MALLOC_ZERO(mem, csz - SIZE_SZ); + return mem; + } +} + +/* + + cfree just calls free. It is needed/defined on some systems + that pair it with calloc, presumably for odd historical reasons. + +*/ + +#if !defined(INTERNAL_LINUX_C_LIB) || !defined(__ELF__) +#if __STD_C +void cfree(Void_t *mem) +#else +void cfree(mem) Void_t *mem; +#endif +{ + fREe(mem); +} +#endif + + + +/* + + Malloc_trim 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. + +*/ + +#if __STD_C +int malloc_trim(size_t pad) +#else +int malloc_trim(pad) size_t pad; +#endif +{ + long top_size; /* Amount of top-most memory */ + long extra; /* Amount to release */ + char* current_brk; /* address returned by pre-check sbrk call */ + char* new_brk; /* address returned by negative sbrk call */ + + unsigned long pagesz = malloc_getpagesize; + + top_size = chunksize(top); + extra = ((top_size - pad - MINSIZE + (pagesz-1)) / pagesz - 1) * pagesz; + + if (extra < (long)pagesz) /* Not enough memory to release */ + return 0; + + else + { + /* Test to make sure no one else called sbrk */ + current_brk = (char*)(MORECORE (0)); + if (current_brk != (char*)(top) + top_size) + return 0; /* Apparently we don't own memory; must fail */ + + else + { + new_brk = (char*)(MORECORE (-extra)); + + if (new_brk == (char*)(MORECORE_FAILURE)) /* sbrk failed? */ + { + /* Try to figure out what we have */ + current_brk = (char*)(MORECORE (0)); + top_size = current_brk - (char*)top; + if (top_size >= (long)MINSIZE) /* if not, we are very very dead! */ + { + sbrked_mem = current_brk - sbrk_base; + set_head(top, top_size | PREV_INUSE); + } + check_chunk(top); + return 0; + } + + else + { + /* Success. Adjust top accordingly. */ + set_head(top, (top_size - extra) | PREV_INUSE); + sbrked_mem -= extra; + check_chunk(top); + return 1; + } + } + } +} + + + +/* + malloc_usable_size: + + This routine tells you how many bytes you can actually use in an + allocated chunk, which may be more than you requested (although + often not). You can use this many bytes without worrying about + overwriting other allocated objects. Not a particularly great + programming practice, but still sometimes useful. + +*/ + +#if __STD_C +size_t malloc_usable_size(Void_t* mem) +#else +size_t malloc_usable_size(mem) Void_t* mem; +#endif +{ + mchunkptr p; + if (mem == NULL) + return 0; + else + { + p = mem2chunk(mem); + if(!chunk_is_mmapped(p)) + { + if (!inuse(p)) return 0; + check_inuse_chunk(p); + return chunksize(p) - SIZE_SZ; + } + return chunksize(p) - 2*SIZE_SZ; + } +} + + + + +/* Utility to update current_mallinfo for malloc_stats and mallinfo() */ + +#ifdef DEBUG +static void malloc_update_mallinfo() +{ + int i; + mbinptr b; + mchunkptr p; +#ifdef DEBUG + mchunkptr q; +#endif + + INTERNAL_SIZE_T avail = chunksize(top); + int navail = ((long)(avail) >= (long)MINSIZE)? 1 : 0; + + for (i = 1; i < NAV; ++i) + { + b = bin_at(i); + for (p = last(b); p != b; p = p->bk) + { +#ifdef DEBUG + check_free_chunk(p); + for (q = next_chunk(p); + q < top && inuse(q) && (long)(chunksize(q)) >= (long)MINSIZE; + q = next_chunk(q)) + check_inuse_chunk(q); +#endif + avail += chunksize(p); + navail++; + } + } + + current_mallinfo.ordblks = navail; + current_mallinfo.uordblks = sbrked_mem - avail; + current_mallinfo.fordblks = avail; + current_mallinfo.hblks = n_mmaps; + current_mallinfo.hblkhd = mmapped_mem; + current_mallinfo.keepcost = chunksize(top); + +} +#endif /* DEBUG */ + + + +/* + + malloc_stats: + + Prints on the amount of space obtain 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), the maximum + number of simultaneous mmap regions used, 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.) + +*/ + +#ifdef DEBUG +void malloc_stats() +{ + malloc_update_mallinfo(); + printf("max system bytes = %10u\n", + (unsigned int)(max_total_mem)); + printf("system bytes = %10u\n", + (unsigned int)(sbrked_mem + mmapped_mem)); + printf("in use bytes = %10u\n", + (unsigned int)(current_mallinfo.uordblks + mmapped_mem)); +#if HAVE_MMAP + printf("max mmap regions = %10u\n", + (unsigned int)max_n_mmaps); +#endif +} +#endif /* DEBUG */ + +/* + mallinfo returns a copy of updated current mallinfo. +*/ + +#ifdef DEBUG +struct mallinfo mALLINFo() +{ + malloc_update_mallinfo(); + return current_mallinfo; +} +#endif /* DEBUG */ + + + + +/* + mallopt: + + mallopt is the general SVID/XPG interface to 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. + + See descriptions of tunable parameters above. + +*/ + +#if __STD_C +int mALLOPt(int param_number, int value) +#else +int mALLOPt(param_number, value) int param_number; int value; +#endif +{ + switch(param_number) + { + case M_TRIM_THRESHOLD: + trim_threshold = value; return 1; + case M_TOP_PAD: + top_pad = value; return 1; + case M_MMAP_THRESHOLD: + mmap_threshold = value; return 1; + case M_MMAP_MAX: +#if HAVE_MMAP + n_mmaps_max = value; return 1; +#else + if (value != 0) return 0; else n_mmaps_max = value; return 1; +#endif + + default: + return 0; + } +} + +int initf_malloc(void) +{ +#if CONFIG_VAL(SYS_MALLOC_F_LEN) + assert(gd->malloc_base); /* Set up by crt0.S */ + gd->malloc_limit = CONFIG_VAL(SYS_MALLOC_F_LEN); + gd->malloc_ptr = 0; +#endif + + return 0; +} + +/* + +History: + + V2.6.6 Sun Dec 5 07:42:19 1999 Doug Lea (dl at gee) + * return null for negative arguments + * Added Several WIN32 cleanups from Martin C. Fong <mcfong@yahoo.com> + * Add 'LACKS_SYS_PARAM_H' for those systems without 'sys/param.h' + (e.g. WIN32 platforms) + * Cleanup up header file inclusion for WIN32 platforms + * Cleanup code to avoid Microsoft Visual C++ compiler complaints + * Add 'USE_DL_PREFIX' to quickly allow co-existence with existing + memory allocation routines + * Set 'malloc_getpagesize' for WIN32 platforms (needs more work) + * Use 'assert' rather than 'ASSERT' in WIN32 code to conform to + usage of 'assert' in non-WIN32 code + * Improve WIN32 'sbrk()' emulation's 'findRegion()' routine to + avoid infinite loop + * Always call 'fREe()' rather than 'free()' + + V2.6.5 Wed Jun 17 15:57:31 1998 Doug Lea (dl at gee) + * Fixed ordering problem with boundary-stamping + + V2.6.3 Sun May 19 08:17:58 1996 Doug Lea (dl at gee) + * Added pvalloc, as recommended by H.J. Liu + * Added 64bit pointer support mainly from Wolfram Gloger + * Added anonymously donated WIN32 sbrk emulation + * Malloc, calloc, getpagesize: add optimizations from Raymond Nijssen + * malloc_extend_top: fix mask error that caused wastage after + foreign sbrks + * Add linux mremap support code from HJ Liu + + V2.6.2 Tue Dec 5 06:52:55 1995 Doug Lea (dl at gee) + * Integrated most documentation with the code. + * Add support for mmap, with help from + Wolfram Gloger (Gloger@lrz.uni-muenchen.de). + * Use last_remainder in more cases. + * Pack bins using idea from colin@nyx10.cs.du.edu + * Use ordered bins instead of best-fit threshhold + * Eliminate block-local decls to simplify tracing and debugging. + * Support another case of realloc via move into top + * Fix error occuring when initial sbrk_base not word-aligned. + * Rely on page size for units instead of SBRK_UNIT to + avoid surprises about sbrk alignment conventions. + * Add mallinfo, mallopt. Thanks to Raymond Nijssen + (raymond@es.ele.tue.nl) for the suggestion. + * Add `pad' argument to malloc_trim and top_pad mallopt parameter. + * More precautions for cases where other routines call sbrk, + courtesy of Wolfram Gloger (Gloger@lrz.uni-muenchen.de). + * Added macros etc., allowing use in linux libc from + H.J. Lu (hjl@gnu.ai.mit.edu) + * Inverted this history list + + V2.6.1 Sat Dec 2 14:10:57 1995 Doug Lea (dl at gee) + * Re-tuned and fixed to behave more nicely with V2.6.0 changes. + * Removed all preallocation code since under current scheme + the work required to undo bad preallocations exceeds + the work saved in good cases for most test programs. + * No longer use return list or unconsolidated bins since + no scheme using them consistently outperforms those that don't + given above changes. + * Use best fit for very large chunks to prevent some worst-cases. + * Added some support for debugging + + V2.6.0 Sat Nov 4 07:05:23 1995 Doug Lea (dl at gee) + * Removed footers when chunks are in use. Thanks to + Paul Wilson (wilson@cs.texas.edu) for the suggestion. + + V2.5.4 Wed Nov 1 07:54:51 1995 Doug Lea (dl at gee) + * Added malloc_trim, with help from Wolfram Gloger + (wmglo@Dent.MED.Uni-Muenchen.DE). + + V2.5.3 Tue Apr 26 10:16:01 1994 Doug Lea (dl at g) + + V2.5.2 Tue Apr 5 16:20:40 1994 Doug Lea (dl at g) + * realloc: try to expand in both directions + * malloc: swap order of clean-bin strategy; + * realloc: only conditionally expand backwards + * Try not to scavenge used bins + * Use bin counts as a guide to preallocation + * Occasionally bin return list chunks in first scan + * Add a few optimizations from colin@nyx10.cs.du.edu + + V2.5.1 Sat Aug 14 15:40:43 1993 Doug Lea (dl at g) + * faster bin computation & slightly different binning + * merged all consolidations to one part of malloc proper + (eliminating old malloc_find_space & malloc_clean_bin) + * Scan 2 returns chunks (not just 1) + * Propagate failure in realloc if malloc returns 0 + * Add stuff to allow compilation on non-ANSI compilers + from kpv@research.att.com + + V2.5 Sat Aug 7 07:41:59 1993 Doug Lea (dl at g.oswego.edu) + * removed potential for odd address access in prev_chunk + * removed dependency on getpagesize.h + * misc cosmetics and a bit more internal documentation + * anticosmetics: mangled names in macros to evade debugger strangeness + * tested on sparc, hp-700, dec-mips, rs6000 + with gcc & native cc (hp, dec only) allowing + Detlefs & Zorn comparison study (in SIGPLAN Notices.) + + Trial version Fri Aug 28 13:14:29 1992 Doug Lea (dl at g.oswego.edu) + * Based loosely on libg++-1.2X malloc. (It retains some of the overall + structure of old version, but most details differ.) + +*/ |