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 = malloc(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                 return error("Object %s not a commit",
  59                              sha1_to_hex(item->object.sha1));
  60         get_sha1_hex(bufptr + 5, parent);
  61         item->tree = lookup_tree(parent);
  62         if (item->tree)
  63                 add_ref(&item->object, &item->tree->object);
  64         bufptr += 46; /* "tree " + "hex sha1" + "\n" */
  65         while (!memcmp(bufptr, "parent ", 7) &&
  66                !get_sha1_hex(bufptr + 7, parent)) {
  67                 struct commit *new_parent = lookup_commit(parent);
  68                 if (new_parent) {
  69                         commit_list_insert(new_parent, &item->parents);
  70                         add_ref(&item->object, &new_parent->object);
  71                 }
  72                 bufptr += 48;
  73         }
  74         item->date = parse_commit_date(bufptr);
  75         free(buffer);
  76         return 0;
  77 }
  78
  79 void commit_list_insert(struct commit *item, struct commit_list **list_p)
  80 {
  81         struct commit_list *new_list = malloc(sizeof(struct commit_list));
  82         new_list->item = item;
  83         new_list->next = *list_p;
  84         *list_p = new_list;
  85 }
  86
  87 void free_commit_list(struct commit_list *list)
  88 {
  89         while (list) {
  90                 struct commit_list *temp = list;
  91                 list = temp->next;
  92                 free(temp);
  93         }
  94 }
  95
  96 static void insert_by_date(struct commit_list **list, struct commit *item)
  97 {
  98         struct commit_list **pp = list;
  99         struct commit_list *p;
 100         while ((p = *pp) != NULL) {
 101                 if (p->item->date < item->date) {
 102                         break;
 103                 }
 104                 pp = &p->next;
 105         }
 106         commit_list_insert(item, pp);
 107 }
 108
 109
 110 void sort_by_date(struct commit_list **list)
 111 {
 112         struct commit_list *ret = NULL;
 113         while (*list) {
 114                 insert_by_date(&ret, (*list)->item);
 115                 *list = (*list)->next;
 116         }
 117         *list = ret;
 118 }
 119
 120 struct commit *pop_most_recent_commit(struct commit_list **list,
 121                                       unsigned int mark)
 122 {
 123         struct commit *ret = (*list)->item;
 124         struct commit_list *parents = ret->parents;
 125         struct commit_list *old = *list;
 126
 127         *list = (*list)->next;
 128         free(old);
 129
 130         while (parents) {
 131                 struct commit *commit = parents->item;
 132                 parse_commit(commit);
 133                 if (!(commit->object.flags & mark)) {
 134                         commit->object.flags |= mark;
 135                         insert_by_date(list, commit);
 136                 }
 137                 parents = parents->next;
 138         }
 139         return ret;
 140 }