[PATCH] show-diff.c: simplify show_diff_empty.
[alt-git.git] / commit.c
blobeda45d7e15358ed6f2cd0502de2a08987307fc98
1 #include "commit.h"
2 #include "cache.h"
3 #include <string.h>
5 const char *commit_type = "commit";
7 struct commit *lookup_commit(unsigned char *sha1)
9 struct object *obj = lookup_object(sha1);
10 if (!obj) {
11 struct commit *ret = malloc(sizeof(struct commit));
12 memset(ret, 0, sizeof(struct commit));
13 created_object(sha1, &ret->object);
14 return ret;
16 if (obj->parsed && obj->type != commit_type) {
17 error("Object %s is a %s, not a commit",
18 sha1_to_hex(sha1), obj->type);
19 return NULL;
21 return (struct commit *) obj;
24 static unsigned long parse_commit_date(const char *buf)
26 unsigned long date;
28 if (memcmp(buf, "author", 6))
29 return 0;
30 while (*buf++ != '\n')
31 /* nada */;
32 if (memcmp(buf, "committer", 9))
33 return 0;
34 while (*buf++ != '>')
35 /* nada */;
36 date = strtoul(buf, NULL, 10);
37 if (date == ULONG_MAX)
38 date = 0;
39 return date;
42 int parse_commit(struct commit *item)
44 char type[20];
45 void * buffer, *bufptr;
46 unsigned long size;
47 unsigned char parent[20];
48 if (item->object.parsed)
49 return 0;
50 item->object.parsed = 1;
51 buffer = bufptr = read_sha1_file(item->object.sha1, type, &size);
52 if (!buffer)
53 return error("Could not read %s",
54 sha1_to_hex(item->object.sha1));
55 if (strcmp(type, commit_type))
56 return error("Object %s not a commit",
57 sha1_to_hex(item->object.sha1));
58 item->object.type = commit_type;
59 get_sha1_hex(bufptr + 5, parent);
60 item->tree = lookup_tree(parent);
61 add_ref(&item->object, &item->tree->object);
62 bufptr += 46; /* "tree " + "hex sha1" + "\n" */
63 while (!memcmp(bufptr, "parent ", 7) &&
64 !get_sha1_hex(bufptr + 7, parent)) {
65 struct commit_list *new_parent =
66 malloc(sizeof(struct commit_list));
67 new_parent->next = item->parents;
68 new_parent->item = lookup_commit(parent);
69 add_ref(&item->object, &new_parent->item->object);
70 item->parents = new_parent;
71 bufptr += 48;
73 item->date = parse_commit_date(bufptr);
74 free(buffer);
75 return 0;
78 void free_commit_list(struct commit_list *list)
80 while (list) {
81 struct commit_list *temp = list;
82 list = temp->next;
83 free(temp);