com32/lib/sys/module/elfutils.c

   1 #include <stdlib.h>
   2 #include <errno.h>
   3
   4 #include "elfutils.h"
   5
   6 unsigned long elf_hash(const unsigned char *name) {
   7         unsigned long h = 0;
   8         unsigned long g;
   9
  10         while (*name) {
  11                 h = (h << 4) + *name++;
  12                 if ((g = h & 0xF0000000))
  13                         h ^= g >> 24;
  14
  15                 h &= ~g;
  16         }
  17
  18         return h;
  19 }
  20
  21 unsigned long elf_gnu_hash(const unsigned char *name) {
  22         unsigned long h = 5381;
  23         unsigned char c;
  24
  25         for (c = *name; c != '\0'; c = *++name) {
  26                 h = h * 33 + c;
  27         }
  28
  29         return h & 0xFFFFFFFF;
  30 }
  31
  32 #ifndef HAVE_ELF_POSIX_MEMALIGN
  33
  34 struct memalign_info {
  35         void    *start_addr;
  36         char    data[0];
  37 };
  38
  39 int elf_malloc(void **memptr, size_t alignment, size_t size) {
  40         char *start_addr = NULL;
  41         struct memalign_info *info;
  42
  43         if ((alignment & (alignment - 1)) != 0)
  44                 return EINVAL;
  45         if (alignment % sizeof(void*) != 0)
  46                 alignment = sizeof(void*);
  47
  48         start_addr = malloc(size + (alignment > sizeof(struct memalign_info) ?
  49                                         alignment : sizeof(struct memalign_info)));
  50
  51         if (start_addr == NULL)
  52                 return ENOMEM;
  53
  54
  55         info = (struct memalign_info*)(start_addr -
  56                         ((unsigned long)start_addr % alignment) +
  57                         alignment - sizeof(struct memalign_info));
  58
  59         info->start_addr = start_addr;
  60
  61         *memptr = info->data;
  62
  63         return 0;
  64 }
  65
  66 void elf_free(char *memptr) {
  67         struct memalign_info *info = (struct memalign_info*)(memptr -
  68                         sizeof(struct memalign_info));
  69
  70         free(info->start_addr);
  71 }
  72
  73 #else
  74
  75 int elf_malloc(void **memptr, size_t alignment, size_t size) {
  76         if ((alignment & (alignment - 1)) != 0)
  77                 return EINVAL;
  78
  79         if (alignment % sizeof(void*) != 0)
  80                 alignment = sizeof(void*);
  81
  82         return posix_memalign(memptr, alignment, size);
  83 }
  84
  85 void elf_free(void *memptr) {
  86         free(memptr);
  87 }
  88
  89 #endif //HAVE_ELF_POSIX_MEMALIGN