hex.c

   1 #include "git-compat-util.h"
   2 #include "hash.h"
   3 #include "hex.h"
   4
   5 const signed char hexval_table[256] = {
   6          -1, -1, -1, -1, -1, -1, -1, -1,                /* 00-07 */
   7          -1, -1, -1, -1, -1, -1, -1, -1,                /* 08-0f */
   8          -1, -1, -1, -1, -1, -1, -1, -1,                /* 10-17 */
   9          -1, -1, -1, -1, -1, -1, -1, -1,                /* 18-1f */
  10          -1, -1, -1, -1, -1, -1, -1, -1,                /* 20-27 */
  11          -1, -1, -1, -1, -1, -1, -1, -1,                /* 28-2f */
  12           0,  1,  2,  3,  4,  5,  6,  7,                /* 30-37 */
  13           8,  9, -1, -1, -1, -1, -1, -1,                /* 38-3f */
  14          -1, 10, 11, 12, 13, 14, 15, -1,                /* 40-47 */
  15          -1, -1, -1, -1, -1, -1, -1, -1,                /* 48-4f */
  16          -1, -1, -1, -1, -1, -1, -1, -1,                /* 50-57 */
  17          -1, -1, -1, -1, -1, -1, -1, -1,                /* 58-5f */
  18          -1, 10, 11, 12, 13, 14, 15, -1,                /* 60-67 */
  19          -1, -1, -1, -1, -1, -1, -1, -1,                /* 68-67 */
  20          -1, -1, -1, -1, -1, -1, -1, -1,                /* 70-77 */
  21          -1, -1, -1, -1, -1, -1, -1, -1,                /* 78-7f */
  22          -1, -1, -1, -1, -1, -1, -1, -1,                /* 80-87 */
  23          -1, -1, -1, -1, -1, -1, -1, -1,                /* 88-8f */
  24          -1, -1, -1, -1, -1, -1, -1, -1,                /* 90-97 */
  25          -1, -1, -1, -1, -1, -1, -1, -1,                /* 98-9f */
  26          -1, -1, -1, -1, -1, -1, -1, -1,                /* a0-a7 */
  27          -1, -1, -1, -1, -1, -1, -1, -1,                /* a8-af */
  28          -1, -1, -1, -1, -1, -1, -1, -1,                /* b0-b7 */
  29          -1, -1, -1, -1, -1, -1, -1, -1,                /* b8-bf */
  30          -1, -1, -1, -1, -1, -1, -1, -1,                /* c0-c7 */
  31          -1, -1, -1, -1, -1, -1, -1, -1,                /* c8-cf */
  32          -1, -1, -1, -1, -1, -1, -1, -1,                /* d0-d7 */
  33          -1, -1, -1, -1, -1, -1, -1, -1,                /* d8-df */
  34          -1, -1, -1, -1, -1, -1, -1, -1,                /* e0-e7 */
  35          -1, -1, -1, -1, -1, -1, -1, -1,                /* e8-ef */
  36          -1, -1, -1, -1, -1, -1, -1, -1,                /* f0-f7 */
  37          -1, -1, -1, -1, -1, -1, -1, -1,                /* f8-ff */
  38 };
  39
  40 int hex_to_bytes(unsigned char *binary, const char *hex, size_t len)
  41 {
  42         for (; len; len--, hex += 2) {
  43                 unsigned int val = (hexval(hex[0]) << 4) | hexval(hex[1]);
  44
  45                 if (val & ~0xff)
  46                         return -1;
  47                 *binary++ = val;
  48         }
  49         return 0;
  50 }
  51
  52 static int get_hash_hex_algop(const char *hex, unsigned char *hash,
  53                               const struct git_hash_algo *algop)
  54 {
  55         int i;
  56         for (i = 0; i < algop->rawsz; i++) {
  57                 int val = hex2chr(hex);
  58                 if (val < 0)
  59                         return -1;
  60                 *hash++ = val;
  61                 hex += 2;
  62         }
  63         return 0;
  64 }
  65
  66 int get_hash_hex(const char *hex, unsigned char *sha1)
  67 {
  68         return get_hash_hex_algop(hex, sha1, the_hash_algo);
  69 }
  70
  71 int get_oid_hex_algop(const char *hex, struct object_id *oid,
  72                       const struct git_hash_algo *algop)
  73 {
  74         int ret = get_hash_hex_algop(hex, oid->hash, algop);
  75         if (!ret)
  76                 oid_set_algo(oid, algop);
  77         return ret;
  78 }
  79
  80 /*
  81  * NOTE: This function relies on hash algorithms being in order from shortest
  82  * length to longest length.
  83  */
  84 int get_oid_hex_any(const char *hex, struct object_id *oid)
  85 {
  86         int i;
  87         for (i = GIT_HASH_NALGOS - 1; i > 0; i--) {
  88                 if (!get_oid_hex_algop(hex, oid, &hash_algos[i]))
  89                         return i;
  90         }
  91         return GIT_HASH_UNKNOWN;
  92 }
  93
  94 int get_oid_hex(const char *hex, struct object_id *oid)
  95 {
  96         return get_oid_hex_algop(hex, oid, the_hash_algo);
  97 }
  98
  99 int parse_oid_hex_algop(const char *hex, struct object_id *oid,
 100                         const char **end,
 101                         const struct git_hash_algo *algop)
 102 {
 103         int ret = get_oid_hex_algop(hex, oid, algop);
 104         if (!ret)
 105                 *end = hex + algop->hexsz;
 106         return ret;
 107 }
 108
 109 int parse_oid_hex_any(const char *hex, struct object_id *oid, const char **end)
 110 {
 111         int ret = get_oid_hex_any(hex, oid);
 112         if (ret)
 113                 *end = hex + hash_algos[ret].hexsz;
 114         return ret;
 115 }
 116
 117 int parse_oid_hex(const char *hex, struct object_id *oid, const char **end)
 118 {
 119         return parse_oid_hex_algop(hex, oid, end, the_hash_algo);
 120 }
 121
 122 char *hash_to_hex_algop_r(char *buffer, const unsigned char *hash,
 123                           const struct git_hash_algo *algop)
 124 {
 125         static const char hex[] = "0123456789abcdef";
 126         char *buf = buffer;
 127         int i;
 128
 129         /*
 130          * Our struct object_id has been memset to 0, so default to printing
 131          * using the default hash.
 132          */
 133         if (algop == &hash_algos[0])
 134                 algop = the_hash_algo;
 135
 136         for (i = 0; i < algop->rawsz; i++) {
 137                 unsigned int val = *hash++;
 138                 *buf++ = hex[val >> 4];
 139                 *buf++ = hex[val & 0xf];
 140         }
 141         *buf = '\0';
 142
 143         return buffer;
 144 }
 145
 146 char *oid_to_hex_r(char *buffer, const struct object_id *oid)
 147 {
 148         return hash_to_hex_algop_r(buffer, oid->hash, &hash_algos[oid->algo]);
 149 }
 150
 151 char *hash_to_hex_algop(const unsigned char *hash, const struct git_hash_algo *algop)
 152 {
 153         static int bufno;
 154         static char hexbuffer[4][GIT_MAX_HEXSZ + 1];
 155         bufno = (bufno + 1) % ARRAY_SIZE(hexbuffer);
 156         return hash_to_hex_algop_r(hexbuffer[bufno], hash, algop);
 157 }
 158
 159 char *hash_to_hex(const unsigned char *hash)
 160 {
 161         return hash_to_hex_algop(hash, the_hash_algo);
 162 }
 163
 164 char *oid_to_hex(const struct object_id *oid)
 165 {
 166         return hash_to_hex_algop(oid->hash, &hash_algos[oid->algo]);
 167 }