[PATCH] Fix git rpush.
[git] / 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 }