src/commit.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 <time.h>
  27
  28 #include "common.h"
  29 #include "commit.h"
  30 #include "revwalk.h"
  31 #include "git/odb.h"
  32
  33 const git_oid *git_commit_id(git_commit *c)
  34 {
  35         return &c->id;
  36 }
  37
  38 git_commit *git_commit_lookup(git_revpool *pool, const git_oid *id)
  39 {
  40     git_obj commit_obj;
  41     git_commit *commit = NULL;
  42
  43     if (pool == NULL || pool->db == NULL)
  44         return NULL;
  45
  46     /*
  47      * TODO: check if the commit is already cached in the
  48      * revpool instead of loading it from the odb
  49      */
  50
  51     if (git_odb_read(&commit_obj, pool->db, id) < 0)
  52         return NULL;
  53
  54     if (commit_obj.type != GIT_OBJ_COMMIT)
  55         goto error_cleanup;
  56
  57     commit = git__malloc(sizeof(git_commit));
  58     memset(commit, 0x0, sizeof(git_commit));
  59
  60     git_oid_cpy(&commit->id, id);
  61     commit->pool = pool;
  62
  63     if (git_commit__parse_buffer(commit, commit_obj.data, commit_obj.len) < 0)
  64         goto error_cleanup;
  65
  66     return commit;
  67
  68 error_cleanup:
  69     git_obj_close(&commit_obj);
  70     free(commit);
  71
  72     return NULL;
  73 }
  74
  75 int git_commit__parse_time(time_t *commit_time, char *buffer, const char *buffer_end)
  76 {
  77     if (memcmp(buffer, "author ", 7) != 0)
  78         return -1;
  79
  80     buffer = memchr(buffer, '\n', buffer_end - buffer);
  81     if (buffer == 0 || buffer >= buffer_end)
  82         return -1;
  83
  84     if (memcmp(buffer, "committer ", 10) != 0)
  85         return -1;
  86
  87     buffer = memchr(buffer, '\n', buffer_end - buffer);
  88     if (buffer == 0 || buffer >= buffer_end)
  89         return -1;
  90
  91     *commit_time = strtol(buffer, &buffer, 10);
  92
  93     return (buffer < buffer_end) ? 0 : -1;
  94 }
  95
  96 int git_commit__parse_oid(git_oid *oid, char **buffer_out, const char *buffer_end, const char *header)
  97 {
  98     size_t sha_len = GIT_OID_HEXSZ;
  99     size_t header_len = strlen(header);
 100
 101     char *buffer = *buffer_out;
 102
 103     if (buffer + (header_len + sha_len + 1) > buffer_end)
 104         return -1;
 105
 106     if (memcmp(buffer, header, header_len) != 0)
 107         return -1;
 108
 109     if (buffer[header_len + sha_len] != '\n')
 110         return -1;
 111
 112     if (git_oid_mkstr(oid, buffer + header_len) < 0)
 113         return -1;
 114
 115     *buffer_out = buffer + (header_len + sha_len + 1);
 116
 117     return 0;
 118 }
 119
 120 int git_commit__parse_buffer(git_commit *commit, void *data, size_t len)
 121 {
 122     char *buffer = (char *)data;
 123     const char *buffer_end = (char *)data + len;
 124
 125     git_oid oid;
 126
 127     if (commit->parsed)
 128                 return 0;
 129
 130     if (git_commit__parse_oid(&oid, &buffer, buffer_end, "tree ") < 0)
 131         return -1;
 132
 133     /*
 134      * TODO: load tree into commit object
 135      * TODO: commit grafts!
 136      */
 137
 138     while (git_commit__parse_oid(&oid, &buffer, buffer_end, "parent ") == 0) {
 139         git_commit *parent;
 140
 141         if ((parent = git_commit_lookup(commit->pool, &oid)) == NULL)
 142             return -1;
 143
 144         // TODO: push the new commit into the revpool
 145     }
 146
 147     if (git_commit__parse_time(&commit->commit_time, buffer, buffer_end) < 0)
 148         return -1;
 149
 150     commit->parsed = 1;
 151
 152     return 0;
 153 }
 154