src/oid.c

   1 /*
   2  * This file is free software; you can redistribute it and/or modify
   3  * it under the terms of the GNU General Public License, version 2,
   4  * as published by the Free Software Foundation.
   5  *
   6  * In addition to the permissions in the GNU General Public License,
   7  * the authors give you unlimited permission to link the compiled
   8  * version of this file into combinations with other programs,
   9  * and to distribute those combinations without any restriction
  10  * coming from the use of this file.  (The General Public License
  11  * restrictions do apply in other respects; for example, they cover
  12  * modification of the file, and distribution when not linked into
  13  * a combined executable.)
  14  *
  15  * This file is distributed in the hope that it will be useful, but
  16  * WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  18  * General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU General Public License
  21  * along with this program; see the file COPYING.  If not, write to
  22  * the Free Software Foundation, 51 Franklin Street, Fifth Floor,
  23  * Boston, MA 02110-1301, USA.
  24  */
  25
  26 #include "common.h"
  27 #include "git/oid.h"
  28 #include <string.h>
  29
  30 static signed char from_hex[] = {
  31 -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, /* 00 */
  32 -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, /* 10 */
  33 -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, /* 20 */
  34  0,  1,  2,  3,  4,  5,  6,  7,  8,  9, -1, -1, -1, -1, -1, -1, /* 30 */
  35 -1, 10, 11, 12, 13, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1, -1, /* 40 */
  36 -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, /* 50 */
  37 -1, 10, 11, 12, 13, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1, -1, /* 60 */
  38 -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, /* 70 */
  39 -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, /* 80 */
  40 -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, /* 90 */
  41 -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, /* a0 */
  42 -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, /* b0 */
  43 -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, /* c0 */
  44 -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, /* d0 */
  45 -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, /* e0 */
  46 -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, /* f0 */
  47 };
  48 static char to_hex[] = "0123456789abcdef";
  49
  50 int git_oid_mkstr(git_oid *out, const char *str)
  51 {
  52         size_t p;
  53         for (p = 0; p < sizeof(out->id); p++, str += 2) {
  54                 int v = (from_hex[(unsigned char)str[0]] << 4)
  55                        | from_hex[(unsigned char)str[1]];
  56                 if (v < 0)
  57                         return GIT_ENOTOID;
  58                 out->id[p] = (unsigned char)v;
  59         }
  60         return GIT_SUCCESS;
  61 }
  62
  63 GIT_INLINE(char) *fmt_one(char *str, unsigned int val)
  64 {
  65         *str++ = to_hex[val >> 4];
  66         *str++ = to_hex[val & 0xf];
  67         return str;
  68 }
  69
  70 void git_oid_fmt(char *str, const git_oid *oid)
  71 {
  72         size_t i;
  73
  74         for (i = 0; i < sizeof(oid->id); i++)
  75                 str = fmt_one(str, oid->id[i]);
  76 }
  77
  78 void git_oid_pathfmt(char *str, const git_oid *oid)
  79 {
  80         size_t i;
  81
  82         str = fmt_one(str, oid->id[0]);
  83         *str++ = '/';
  84         for (i = 1; i < sizeof(oid->id); i++)
  85                 str = fmt_one(str, oid->id[i]);
  86 }
  87
  88 char *git_oid_allocfmt(const git_oid *oid)
  89 {
  90         char *str = git__malloc(GIT_OID_HEXSZ + 1);
  91         if (!str)
  92                 return NULL;
  93         git_oid_fmt(str, oid);
  94         str[GIT_OID_HEXSZ] = '\0';
  95         return str;
  96 }
  97
  98 char *git_oid_to_string(char *out, size_t n, const git_oid *oid)
  99 {
 100         char str[GIT_OID_HEXSZ];
 101
 102         if (!out || n == 0 || !oid)
 103                 return "";
 104
 105         n--;  /* allow room for terminating NUL */
 106
 107         if (n > 0) {
 108                 git_oid_fmt(str, oid);
 109                 if (n > GIT_OID_HEXSZ)
 110                         n = GIT_OID_HEXSZ;
 111                 memcpy(out, str, n);
 112         }
 113
 114         out[n] = '\0';
 115
 116         return out;
 117 }
 118