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_buffer(struct commit *item, void *buffer, unsigned long size)
  45 {
  46         void *bufptr = buffer;
  47         unsigned char parent[20];
  48
  49         if (item->object.parsed)
  50                 return 0;
  51         item->object.parsed = 1;
  52         get_sha1_hex(bufptr + 5, parent);
  53         item->tree = lookup_tree(parent);
  54         if (item->tree)
  55                 add_ref(&item->object, &item->tree->object);
  56         bufptr += 46; /* "tree " + "hex sha1" + "\n" */
  57         while (!memcmp(bufptr, "parent ", 7) &&
  58                !get_sha1_hex(bufptr + 7, parent)) {
  59                 struct commit *new_parent = lookup_commit(parent);
  60                 if (new_parent) {
  61                         commit_list_insert(new_parent, &item->parents);
  62                         add_ref(&item->object, &new_parent->object);
  63                 }
  64                 bufptr += 48;
  65         }
  66         item->date = parse_commit_date(bufptr);
  67         return 0;
  68 }
  69
  70 int parse_commit(struct commit *item)
  71 {
  72         char type[20];
  73         void *buffer;
  74         unsigned long size;
  75         int ret;
  76
  77         if (item->object.parsed)
  78                 return 0;
  79         buffer = read_sha1_file(item->object.sha1, type, &size);
  80         if (!buffer)
  81                 return error("Could not read %s",
  82                              sha1_to_hex(item->object.sha1));
  83         if (strcmp(type, commit_type)) {
  84                 free(buffer);
  85                 return error("Object %s not a commit",
  86                              sha1_to_hex(item->object.sha1));
  87         }
  88         ret = parse_commit_buffer(item, buffer, size);
  89         free(buffer);
  90         return ret;
  91 }
  92
  93 void commit_list_insert(struct commit *item, struct commit_list **list_p)
  94 {
  95         struct commit_list *new_list = xmalloc(sizeof(struct commit_list));
  96         new_list->item = item;
  97         new_list->next = *list_p;
  98         *list_p = new_list;
  99 }
 100
 101 void free_commit_list(struct commit_list *list)
 102 {
 103         while (list) {
 104                 struct commit_list *temp = list;
 105                 list = temp->next;
 106                 free(temp);
 107         }
 108 }
 109
 110 static void insert_by_date(struct commit_list **list, struct commit *item)
 111 {
 112         struct commit_list **pp = list;
 113         struct commit_list *p;
 114         while ((p = *pp) != NULL) {
 115                 if (p->item->date < item->date) {
 116                         break;
 117                 }
 118                 pp = &p->next;
 119         }
 120         commit_list_insert(item, pp);
 121 }
 122
 123
 124 void sort_by_date(struct commit_list **list)
 125 {
 126         struct commit_list *ret = NULL;
 127         while (*list) {
 128                 insert_by_date(&ret, (*list)->item);
 129                 *list = (*list)->next;
 130         }
 131         *list = ret;
 132 }
 133
 134 struct commit *pop_most_recent_commit(struct commit_list **list,
 135                                       unsigned int mark)
 136 {
 137         struct commit *ret = (*list)->item;
 138         struct commit_list *parents = ret->parents;
 139         struct commit_list *old = *list;
 140
 141         *list = (*list)->next;
 142         free(old);
 143
 144         while (parents) {
 145                 struct commit *commit = parents->item;
 146                 parse_commit(commit);
 147                 if (!(commit->object.flags & mark)) {
 148                         commit->object.flags |= mark;
 149                         insert_by_date(list, commit);
 150                 }
 151                 parents = parents->next;
 152         }
 153         return ret;
 154 }