hex.c

   1 #include "git-compat-util.h"
   2 #include "hex.h"
   3
   4 const signed char hexval_table[256] = {
   5          -1, -1, -1, -1, -1, -1, -1, -1,                /* 00-07 */
   6          -1, -1, -1, -1, -1, -1, -1, -1,                /* 08-0f */
   7          -1, -1, -1, -1, -1, -1, -1, -1,                /* 10-17 */
   8          -1, -1, -1, -1, -1, -1, -1, -1,                /* 18-1f */
   9          -1, -1, -1, -1, -1, -1, -1, -1,                /* 20-27 */
  10          -1, -1, -1, -1, -1, -1, -1, -1,                /* 28-2f */
  11           0,  1,  2,  3,  4,  5,  6,  7,                /* 30-37 */
  12           8,  9, -1, -1, -1, -1, -1, -1,                /* 38-3f */
  13          -1, 10, 11, 12, 13, 14, 15, -1,                /* 40-47 */
  14          -1, -1, -1, -1, -1, -1, -1, -1,                /* 48-4f */
  15          -1, -1, -1, -1, -1, -1, -1, -1,                /* 50-57 */
  16          -1, -1, -1, -1, -1, -1, -1, -1,                /* 58-5f */
  17          -1, 10, 11, 12, 13, 14, 15, -1,                /* 60-67 */
  18          -1, -1, -1, -1, -1, -1, -1, -1,                /* 68-67 */
  19          -1, -1, -1, -1, -1, -1, -1, -1,                /* 70-77 */
  20          -1, -1, -1, -1, -1, -1, -1, -1,                /* 78-7f */
  21          -1, -1, -1, -1, -1, -1, -1, -1,                /* 80-87 */
  22          -1, -1, -1, -1, -1, -1, -1, -1,                /* 88-8f */
  23          -1, -1, -1, -1, -1, -1, -1, -1,                /* 90-97 */
  24          -1, -1, -1, -1, -1, -1, -1, -1,                /* 98-9f */
  25          -1, -1, -1, -1, -1, -1, -1, -1,                /* a0-a7 */
  26          -1, -1, -1, -1, -1, -1, -1, -1,                /* a8-af */
  27          -1, -1, -1, -1, -1, -1, -1, -1,                /* b0-b7 */
  28          -1, -1, -1, -1, -1, -1, -1, -1,                /* b8-bf */
  29          -1, -1, -1, -1, -1, -1, -1, -1,                /* c0-c7 */
  30          -1, -1, -1, -1, -1, -1, -1, -1,                /* c8-cf */
  31          -1, -1, -1, -1, -1, -1, -1, -1,                /* d0-d7 */
  32          -1, -1, -1, -1, -1, -1, -1, -1,                /* d8-df */
  33          -1, -1, -1, -1, -1, -1, -1, -1,                /* e0-e7 */
  34          -1, -1, -1, -1, -1, -1, -1, -1,                /* e8-ef */
  35          -1, -1, -1, -1, -1, -1, -1, -1,                /* f0-f7 */
  36          -1, -1, -1, -1, -1, -1, -1, -1,                /* f8-ff */
  37 };
  38
  39 int hex_to_bytes(unsigned char *binary, const char *hex, size_t len)
  40 {
  41         for (; len; len--, hex += 2) {
  42                 unsigned int val = (hexval(hex[0]) << 4) | hexval(hex[1]);
  43
  44                 if (val & ~0xff)
  45                         return -1;
  46                 *binary++ = val;
  47         }
  48         return 0;
  49 }
  50
  51 static int get_hash_hex_algop(const char *hex, unsigned char *hash,
  52                               const struct git_hash_algo *algop)
  53 {
  54         int i;
  55         for (i = 0; i < algop->rawsz; i++) {
  56                 int val = hex2chr(hex);
  57                 if (val < 0)
  58                         return -1;
  59                 *hash++ = val;
  60                 hex += 2;
  61         }
  62         return 0;
  63 }
  64
  65 int get_sha1_hex(const char *hex, unsigned char *sha1)
  66 {
  67         return get_hash_hex_algop(hex, sha1, the_hash_algo);
  68 }
  69
  70 int get_oid_hex_algop(const char *hex, struct object_id *oid,
  71                       const struct git_hash_algo *algop)
  72 {
  73         int ret = get_hash_hex_algop(hex, oid->hash, algop);
  74         if (!ret)
  75                 oid_set_algo(oid, algop);
  76         return ret;
  77 }
  78
  79 /*
  80  * NOTE: This function relies on hash algorithms being in order from shortest
  81  * length to longest length.
  82  */
  83 int get_oid_hex_any(const char *hex, struct object_id *oid)
  84 {
  85         int i;
  86         for (i = GIT_HASH_NALGOS - 1; i > 0; i--) {
  87                 if (!get_oid_hex_algop(hex, oid, &hash_algos[i]))
  88                         return i;
  89         }
  90         return GIT_HASH_UNKNOWN;
  91 }
  92
  93 int get_oid_hex(const char *hex, struct object_id *oid)
  94 {
  95         return get_oid_hex_algop(hex, oid, the_hash_algo);
  96 }
  97
  98 int parse_oid_hex_algop(const char *hex, struct object_id *oid,
  99                         const char **end,
 100                         const struct git_hash_algo *algop)
 101 {
 102         int ret = get_oid_hex_algop(hex, oid, algop);
 103         if (!ret)
 104                 *end = hex + algop->hexsz;
 105         return ret;
 106 }
 107
 108 int parse_oid_hex_any(const char *hex, struct object_id *oid, const char **end)
 109 {
 110         int ret = get_oid_hex_any(hex, oid);
 111         if (ret)
 112                 *end = hex + hash_algos[ret].hexsz;
 113         return ret;
 114 }
 115
 116 int parse_oid_hex(const char *hex, struct object_id *oid, const char **end)
 117 {
 118         return parse_oid_hex_algop(hex, oid, end, the_hash_algo);
 119 }
 120
 121 char *hash_to_hex_algop_r(char *buffer, const unsigned char *hash,
 122                           const struct git_hash_algo *algop)
 123 {
 124         static const char hex[] = "0123456789abcdef";
 125         char *buf = buffer;
 126         int i;
 127
 128         /*
 129          * Our struct object_id has been memset to 0, so default to printing
 130          * using the default hash.
 131          */
 132         if (algop == &hash_algos[0])
 133                 algop = the_hash_algo;
 134
 135         for (i = 0; i < algop->rawsz; i++) {
 136                 unsigned int val = *hash++;
 137                 *buf++ = hex[val >> 4];
 138                 *buf++ = hex[val & 0xf];
 139         }
 140         *buf = '\0';
 141
 142         return buffer;
 143 }
 144
 145 char *oid_to_hex_r(char *buffer, const struct object_id *oid)
 146 {
 147         return hash_to_hex_algop_r(buffer, oid->hash, &hash_algos[oid->algo]);
 148 }
 149
 150 char *hash_to_hex_algop(const unsigned char *hash, const struct git_hash_algo *algop)
 151 {
 152         static int bufno;
 153         static char hexbuffer[4][GIT_MAX_HEXSZ + 1];
 154         bufno = (bufno + 1) % ARRAY_SIZE(hexbuffer);
 155         return hash_to_hex_algop_r(hexbuffer[bufno], hash, algop);
 156 }
 157
 158 char *hash_to_hex(const unsigned char *hash)
 159 {
 160         return hash_to_hex_algop(hash, the_hash_algo);
 161 }
 162
 163 char *oid_to_hex(const struct object_id *oid)
 164 {
 165         return hash_to_hex_algop(oid->hash, &hash_algos[oid->algo]);
 166 }