commit.c

   1 #include "tag.h"
   2 #include "commit.h"
   3 #include "cache.h"
   4 #include <string.h>
   5 #include <limits.h>
   6
   7 const char *commit_type = "commit";
   8
   9 static struct commit *check_commit(struct object *obj, unsigned char *sha1)
  10 {
  11         if (obj->type != commit_type) {
  12                 error("Object %s is a %s, not a commit",
  13                       sha1_to_hex(sha1), obj->type);
  14                 return NULL;
  15         }
  16         return (struct commit *) obj;
  17 }
  18
  19 struct commit *lookup_commit_reference(unsigned char *sha1)
  20 {
  21         struct object *obj = parse_object(sha1);
  22
  23         if (!obj)
  24                 return NULL;
  25         if (obj->type == tag_type)
  26                 obj = ((struct tag *)obj)->tagged;
  27         return check_commit(obj, sha1);
  28 }
  29
  30 struct commit *lookup_commit(unsigned char *sha1)
  31 {
  32         struct object *obj = lookup_object(sha1);
  33         if (!obj) {
  34                 struct commit *ret = xmalloc(sizeof(struct commit));
  35                 memset(ret, 0, sizeof(struct commit));
  36                 created_object(sha1, &ret->object);
  37                 ret->object.type = commit_type;
  38                 return ret;
  39         }
  40         if (!obj->type)
  41                 obj->type = commit_type;
  42         return check_commit(obj, sha1);
  43 }
  44
  45 static unsigned long parse_commit_date(const char *buf)
  46 {
  47         unsigned long date;
  48
  49         if (memcmp(buf, "author", 6))
  50                 return 0;
  51         while (*buf++ != '\n')
  52                 /* nada */;
  53         if (memcmp(buf, "committer", 9))
  54                 return 0;
  55         while (*buf++ != '>')
  56                 /* nada */;
  57         date = strtoul(buf, NULL, 10);
  58         if (date == ULONG_MAX)
  59                 date = 0;
  60         return date;
  61 }
  62
  63 int parse_commit_buffer(struct commit *item, void *buffer, unsigned long size)
  64 {
  65         void *bufptr = buffer;
  66         unsigned char parent[20];
  67
  68         if (item->object.parsed)
  69                 return 0;
  70         item->object.parsed = 1;
  71         get_sha1_hex(bufptr + 5, parent);
  72         item->tree = lookup_tree(parent);
  73         if (item->tree)
  74                 add_ref(&item->object, &item->tree->object);
  75         bufptr += 46; /* "tree " + "hex sha1" + "\n" */
  76         while (!memcmp(bufptr, "parent ", 7) &&
  77                !get_sha1_hex(bufptr + 7, parent)) {
  78                 struct commit *new_parent = lookup_commit(parent);
  79                 if (new_parent) {
  80                         commit_list_insert(new_parent, &item->parents);
  81                         add_ref(&item->object, &new_parent->object);
  82                 }
  83                 bufptr += 48;
  84         }
  85         item->date = parse_commit_date(bufptr);
  86         return 0;
  87 }
  88
  89 int parse_commit(struct commit *item)
  90 {
  91         char type[20];
  92         void *buffer;
  93         unsigned long size;
  94         int ret;
  95
  96         if (item->object.parsed)
  97                 return 0;
  98         buffer = read_sha1_file(item->object.sha1, type, &size);
  99         if (!buffer)
 100                 return error("Could not read %s",
 101                              sha1_to_hex(item->object.sha1));
 102         if (strcmp(type, commit_type)) {
 103                 free(buffer);
 104                 return error("Object %s not a commit",
 105                              sha1_to_hex(item->object.sha1));
 106         }
 107         ret = parse_commit_buffer(item, buffer, size);
 108         free(buffer);
 109         return ret;
 110 }
 111
 112 void commit_list_insert(struct commit *item, struct commit_list **list_p)
 113 {
 114         struct commit_list *new_list = xmalloc(sizeof(struct commit_list));
 115         new_list->item = item;
 116         new_list->next = *list_p;
 117         *list_p = new_list;
 118 }
 119
 120 void free_commit_list(struct commit_list *list)
 121 {
 122         while (list) {
 123                 struct commit_list *temp = list;
 124                 list = temp->next;
 125                 free(temp);
 126         }
 127 }
 128
 129 static void insert_by_date(struct commit_list **list, struct commit *item)
 130 {
 131         struct commit_list **pp = list;
 132         struct commit_list *p;
 133         while ((p = *pp) != NULL) {
 134                 if (p->item->date < item->date) {
 135                         break;
 136                 }
 137                 pp = &p->next;
 138         }
 139         commit_list_insert(item, pp);
 140 }
 141
 142
 143 void sort_by_date(struct commit_list **list)
 144 {
 145         struct commit_list *ret = NULL;
 146         while (*list) {
 147                 insert_by_date(&ret, (*list)->item);
 148                 *list = (*list)->next;
 149         }
 150         *list = ret;
 151 }
 152
 153 struct commit *pop_most_recent_commit(struct commit_list **list,
 154                                       unsigned int mark)
 155 {
 156         struct commit *ret = (*list)->item;
 157         struct commit_list *parents = ret->parents;
 158         struct commit_list *old = *list;
 159
 160         *list = (*list)->next;
 161         free(old);
 162
 163         while (parents) {
 164                 struct commit *commit = parents->item;
 165                 parse_commit(commit);
 166                 if (!(commit->object.flags & mark)) {
 167                         commit->object.flags |= mark;
 168                         insert_by_date(list, commit);
 169                 }
 170                 parents = parents->next;
 171         }
 172         return ret;
 173 }