dietlibc-memalign.patch

   1 diff -ur dietlibc-0.31/include/stdlib.h dietlibc-0.31-memalign/include/stdlib.h
   2 --- dietlibc-0.31/include/stdlib.h      2009-03-19 15:39:48.000000000 +0100
   3 +++ dietlibc-0.31-memalign/include/stdlib.h     2009-03-19 15:39:37.000000000 +0100
   4 @@ -13,6 +13,8 @@
   5  void *malloc(size_t size)  __THROW __attribute_malloc__;
   6  void free(void *ptr) __THROW;
   7  void *realloc(void *ptr, size_t size) __THROW __attribute_malloc__;
   8 +void *memalign(size_t alignment, size_t size) __THROW __attribute_malloc__;
   9 +void *valloc(size_t size) __THROW __attribute_malloc__;
  10
  11  char *getenv(const char *name) __THROW __pure;
  12  int putenv(const char *string) __THROW;
  13 diff -ur dietlibc-0.31/lib/alloc.c dietlibc-0.31-memalign/lib/alloc.c
  14 --- dietlibc-0.31/lib/alloc.c   2009-03-19 15:39:48.000000000 +0100
  15 +++ dietlibc-0.31-memalign/lib/alloc.c  2009-03-19 15:38:33.000000000 +0100
  16 @@ -128,10 +128,14 @@
  17  }
  18
  19  /* -- PUBLIC FUNCTIONS ---------------------------------------------------- */
  20 -
  21 +int __libc_free_aligned(void *ptr);
  22  static void _alloc_libc_free(void *ptr) {
  23    register size_t size;
  24 -  if (ptr) {
  25 +  if (ptr == NULL)
  26 +         return;
  27 +  if (__libc_free_aligned(ptr))
  28 +         return;
  29 +
  30      size=((__alloc_t*)BLOCK_START(ptr))->size;
  31      if (size) {
  32        if (size<=__MAX_SMALL_SIZE)
  33 @@ -139,7 +143,6 @@
  34        else
  35         munmap(BLOCK_START(ptr),size);
  36      }
  37 -  }
  38  }
  39  void __libc_free(void *ptr) __attribute__((alias("_alloc_libc_free")));
  40  void free(void *ptr) __attribute__((weak,alias("_alloc_libc_free")));
  41 @@ -268,3 +249,75 @@
  42  }
  43  void* realloc(void* ptr, size_t size) __attribute__((weak,alias("__libc_realloc")));
  44
  45 +/* List of blocks allocated with memalign or valloc */
  46 +struct alignlist {
  47 +       struct alignlist *next;
  48 +       void *aligned;  /* The address that memaligned returned.  */
  49 +       void *exact;    /* The address that malloc returned.  */
  50 +};
  51 +struct alignlist *_aligned_blocks;
  52 +
  53 +/* Return memory to the heap. */
  54 +int __libc_free_aligned(void *ptr);
  55 +int __libc_free_aligned(void *ptr) {
  56 +       struct alignlist *l;
  57 +       register size_t size;
  58 +
  59 +       if (ptr == NULL)
  60 +               return 0;
  61 +
  62 +       for (l = _aligned_blocks; l != NULL; l = l->next) {
  63 +               if (l->aligned == ptr) {
  64 +                       size=((__alloc_t*)BLOCK_START(l->exact))->size;
  65 +                       if (size) {
  66 +                         if (size<=__MAX_SMALL_SIZE)
  67 +                           __small_free(l->exact,size);
  68 +                         else
  69 +                           munmap(BLOCK_START(l->exact),size);
  70 +                       }
  71 +                       /* Mark the block as free */
  72 +                       l->aligned = NULL;
  73 +                       return 1;
  74 +               }
  75 +       }
  76 +       return 0;
  77 +}
  78 +
  79 +void * memalign (size_t alignment, size_t size);
  80 +void * memalign (size_t alignment, size_t size) {
  81 +       void * result;
  82 +       unsigned long int adj;
  83 +
  84 +       result = malloc (size + alignment - 1);
  85 +       if (result == NULL)
  86 +               return NULL;
  87 +
  88 +       adj = (unsigned long int) ((unsigned long int) ((char *) result - (char *) NULL)) % alignment;
  89 +       if (adj != 0) {
  90 +               struct alignlist *l;
  91 +               for (l = _aligned_blocks; l != NULL; l = l->next)
  92 +                       if (l->aligned == NULL)
  93 +                               /* This slot is free.  Use it.  */
  94 +                               break;
  95 +               if (l == NULL) {
  96 +                       l = (struct alignlist *) malloc (sizeof (struct alignlist));
  97 +                       if (l == NULL) {
  98 +                               _alloc_libc_free(result);
  99 +                               result = NULL;
 100 +                               goto DONE;
 101 +                       }
 102 +                       l->next = _aligned_blocks;
 103 +                       _aligned_blocks = l;
 104 +               }
 105 +               l->exact = result;
 106 +               result = l->aligned = (char *) result + alignment - adj;
 107 +       }
 108 +DONE:
 109 +
 110 +       return result;
 111 +}
 112 +
 113 +void * valloc (size_t size);
 114 +void * valloc (size_t size) {
 115 +       return memalign(PAGE_SIZE, size);
 116 +}