src/commit_list.c

   1 /*
   2  * Copyright (C) the libgit2 contributors. All rights reserved.
   3  *
   4  * This file is part of libgit2, distributed under the GNU GPL v2 with
   5  * a Linking Exception. For full terms see the included COPYING file.
   6  */
   7
   8 #include "commit_list.h"
   9 #include "common.h"
  10 #include "revwalk.h"
  11 #include "pool.h"
  12 #include "odb.h"
  13
  14 int git_commit_list_time_cmp(const void *a, const void *b)
  15 {
  16         int64_t time_a = ((git_commit_list_node *) a)->time;
  17         int64_t time_b = ((git_commit_list_node *) b)->time;
  18
  19         if (time_a < time_b)
  20                 return 1;
  21         if (time_a > time_b)
  22                 return -1;
  23
  24         return 0;
  25 }
  26
  27 git_commit_list *git_commit_list_insert(git_commit_list_node *item, git_commit_list **list_p)
  28 {
  29         git_commit_list *new_list = git__malloc(sizeof(git_commit_list));
  30         if (new_list != NULL) {
  31                 new_list->item = item;
  32                 new_list->next = *list_p;
  33         }
  34         *list_p = new_list;
  35         return new_list;
  36 }
  37
  38 git_commit_list *git_commit_list_insert_by_date(git_commit_list_node *item, git_commit_list **list_p)
  39 {
  40         git_commit_list **pp = list_p;
  41         git_commit_list *p;
  42
  43         while ((p = *pp) != NULL) {
  44                 if (git_commit_list_time_cmp(p->item, item) > 0)
  45                         break;
  46
  47                 pp = &p->next;
  48         }
  49
  50         return git_commit_list_insert(item, pp);
  51 }
  52
  53 git_commit_list_node *git_commit_list_alloc_node(git_revwalk *walk)
  54 {
  55         return (git_commit_list_node *)git_pool_mallocz(&walk->commit_pool, 1);
  56 }
  57
  58 static int commit_error(git_commit_list_node *commit, const char *msg)
  59 {
  60         char commit_oid[GIT_OID_HEXSZ + 1];
  61         git_oid_fmt(commit_oid, &commit->oid);
  62         commit_oid[GIT_OID_HEXSZ] = '\0';
  63
  64         giterr_set(GITERR_ODB, "failed to parse commit %s - %s", commit_oid, msg);
  65
  66         return -1;
  67 }
  68
  69 static git_commit_list_node **alloc_parents(
  70         git_revwalk *walk, git_commit_list_node *commit, size_t n_parents)
  71 {
  72         if (n_parents <= PARENTS_PER_COMMIT)
  73                 return (git_commit_list_node **)((char *)commit + sizeof(git_commit_list_node));
  74
  75         return (git_commit_list_node **)git_pool_malloc(
  76                 &walk->commit_pool, (uint32_t)(n_parents * sizeof(git_commit_list_node *)));
  77 }
  78
  79
  80 void git_commit_list_free(git_commit_list **list_p)
  81 {
  82         git_commit_list *list = *list_p;
  83
  84         if (list == NULL)
  85                 return;
  86
  87         while (list) {
  88                 git_commit_list *temp = list;
  89                 list = temp->next;
  90                 git__free(temp);
  91         }
  92
  93         *list_p = NULL;
  94 }
  95
  96 git_commit_list_node *git_commit_list_pop(git_commit_list **stack)
  97 {
  98         git_commit_list *top = *stack;
  99         git_commit_list_node *item = top ? top->item : NULL;
 100
 101         if (top) {
 102                 *stack = top->next;
 103                 git__free(top);
 104         }
 105         return item;
 106 }
 107
 108 static int commit_quick_parse(
 109         git_revwalk *walk,
 110         git_commit_list_node *commit,
 111         const uint8_t *buffer,
 112         size_t buffer_len)
 113 {
 114         const size_t parent_len = strlen("parent ") + GIT_OID_HEXSZ + 1;
 115         const uint8_t *buffer_end = buffer + buffer_len;
 116         const uint8_t *parents_start, *committer_start;
 117         int i, parents = 0;
 118         int64_t commit_time;
 119
 120         buffer += strlen("tree ") + GIT_OID_HEXSZ + 1;
 121
 122         parents_start = buffer;
 123         while (buffer + parent_len < buffer_end && memcmp(buffer, "parent ", strlen("parent ")) == 0) {
 124                 parents++;
 125                 buffer += parent_len;
 126         }
 127
 128         commit->parents = alloc_parents(walk, commit, parents);
 129         GITERR_CHECK_ALLOC(commit->parents);
 130
 131         buffer = parents_start;
 132         for (i = 0; i < parents; ++i) {
 133                 git_oid oid;
 134
 135                 if (git_oid_fromstr(&oid, (const char *)buffer + strlen("parent ")) < 0)
 136                         return -1;
 137
 138                 commit->parents[i] = git_revwalk__commit_lookup(walk, &oid);
 139                 if (commit->parents[i] == NULL)
 140                         return -1;
 141
 142                 buffer += parent_len;
 143         }
 144
 145         commit->out_degree = (unsigned short)parents;
 146
 147         if ((committer_start = buffer = memchr(buffer, '\n', buffer_end - buffer)) == NULL)
 148                 return commit_error(commit, "object is corrupted");
 149
 150         buffer++;
 151
 152         if ((buffer = memchr(buffer, '\n', buffer_end - buffer)) == NULL)
 153                 return commit_error(commit, "object is corrupted");
 154
 155         /* Skip trailing spaces */
 156         while (buffer > committer_start && git__isspace(*buffer))
 157                 buffer--;
 158
 159         /* Seek for the beginning of the pack of digits */
 160         while (buffer > committer_start && git__isdigit(*buffer))
 161                 buffer--;
 162
 163         /* Skip potential timezone offset */
 164         if ((buffer > committer_start) && (*buffer == '+' || *buffer == '-')) {
 165                 buffer--;
 166
 167                 while (buffer > committer_start && git__isspace(*buffer))
 168                         buffer--;
 169
 170                 while (buffer > committer_start && git__isdigit(*buffer))
 171                         buffer--;
 172         }
 173
 174         if ((buffer == committer_start) || (git__strtol64(&commit_time, (char *)(buffer + 1), NULL, 10) < 0))
 175                 return commit_error(commit, "cannot parse commit time");
 176
 177         commit->time = commit_time;
 178         commit->parsed = 1;
 179         return 0;
 180 }
 181
 182 int git_commit_list_parse(git_revwalk *walk, git_commit_list_node *commit)
 183 {
 184         git_odb_object *obj;
 185         int error;
 186
 187         if (commit->parsed)
 188                 return 0;
 189
 190         if ((error = git_odb_read(&obj, walk->odb, &commit->oid)) < 0)
 191                 return error;
 192
 193         if (obj->cached.type != GIT_OBJ_COMMIT) {
 194                 giterr_set(GITERR_INVALID, "object is no commit object");
 195                 error = -1;
 196         } else
 197                 error = commit_quick_parse(
 198                         walk, commit,
 199                         (const uint8_t *)git_odb_object_data(obj),
 200                         git_odb_object_size(obj));
 201
 202         git_odb_object_free(obj);
 203         return error;
 204 }
 205