commit.c

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