headers/libs/libunwind/remote.h

   1 #ifndef REMOTE_H
   2 #define REMOTE_H
   3
   4 /* Helper functions for accessing (remote) memory.  These functions
   5    assume that all addresses are naturally aligned (e.g., 32-bit
   6    quantity is stored at a 32-bit-aligned address.  */
   7
   8 #ifdef UNW_LOCAL_ONLY
   9
  10 static inline int
  11 fetch8 (unw_addr_space_t as, unw_accessors_t *a,
  12         unw_word_t *addr, int8_t *valp, void *arg)
  13 {
  14   *valp = *(int8_t *) (uintptr_t) *addr;
  15   *addr += 1;
  16   return 0;
  17 }
  18
  19 static inline int
  20 fetch16 (unw_addr_space_t as, unw_accessors_t *a,
  21          unw_word_t *addr, int16_t *valp, void *arg)
  22 {
  23   *valp = *(int16_t *) (uintptr_t) *addr;
  24   *addr += 2;
  25   return 0;
  26 }
  27
  28 static inline int
  29 fetch32 (unw_addr_space_t as, unw_accessors_t *a,
  30          unw_word_t *addr, int32_t *valp, void *arg)
  31 {
  32   *valp = *(int32_t *) (uintptr_t) *addr;
  33   *addr += 4;
  34   return 0;
  35 }
  36
  37 static inline int
  38 fetchw (unw_addr_space_t as, unw_accessors_t *a,
  39         unw_word_t *addr, unw_word_t *valp, void *arg)
  40 {
  41   *valp = *(unw_word_t *) (uintptr_t) *addr;
  42   *addr += sizeof (unw_word_t);
  43   return 0;
  44 }
  45
  46 #else /* !UNW_LOCAL_ONLY */
  47
  48 #define WSIZE   (sizeof (unw_word_t))
  49
  50 static inline int
  51 fetch8 (unw_addr_space_t as, unw_accessors_t *a,
  52         unw_word_t *addr, int8_t *valp, void *arg)
  53 {
  54   unw_word_t val, aligned_addr = *addr & -WSIZE, off = *addr - aligned_addr;
  55   int ret;
  56
  57   *addr += 1;
  58
  59   ret = (*a->access_mem) (as, aligned_addr, &val, 0, arg);
  60
  61 #if __BYTE_ORDER == __LITTLE_ENDIAN
  62   val >>= 8*off;
  63 #else
  64   val >>= 8*(WSIZE - 1 - off);
  65 #endif
  66   *valp = val & 0xff;
  67   return ret;
  68 }
  69
  70 static inline int
  71 fetch16 (unw_addr_space_t as, unw_accessors_t *a,
  72          unw_word_t *addr, int16_t *valp, void *arg)
  73 {
  74   unw_word_t val, aligned_addr = *addr & -WSIZE, off = *addr - aligned_addr;
  75   int ret;
  76
  77   assert ((off & 0x1) == 0);
  78
  79   *addr += 2;
  80
  81   ret = (*a->access_mem) (as, aligned_addr, &val, 0, arg);
  82
  83 #if __BYTE_ORDER == __LITTLE_ENDIAN
  84   val >>= 8*off;
  85 #else
  86   val >>= 8*(WSIZE - 2 - off);
  87 #endif
  88   *valp = val & 0xffff;
  89   return ret;
  90 }
  91
  92 static inline int
  93 fetch32 (unw_addr_space_t as, unw_accessors_t *a,
  94          unw_word_t *addr, int32_t *valp, void *arg)
  95 {
  96   unw_word_t val, aligned_addr = *addr & -WSIZE, off = *addr - aligned_addr;
  97   int ret;
  98
  99   assert ((off & 0x3) == 0);
 100
 101   *addr += 4;
 102
 103   ret = (*a->access_mem) (as, aligned_addr, &val, 0, arg);
 104
 105 #if __BYTE_ORDER == __LITTLE_ENDIAN
 106   val >>= 8*off;
 107 #else
 108   val >>= 8*(WSIZE - 4 - off);
 109 #endif
 110   *valp = val & 0xffffffff;
 111   return ret;
 112 }
 113
 114 static inline int
 115 fetchw (unw_addr_space_t as, unw_accessors_t *a,
 116         unw_word_t *addr, unw_word_t *valp, void *arg)
 117 {
 118   int ret;
 119
 120   ret = (*a->access_mem) (as, *addr, valp, 0, arg);
 121   *addr += WSIZE;
 122   return ret;
 123 }
 124
 125 #endif /* !UNW_LOCAL_ONLY */
 126
 127 #endif /* REMOTE_H */