commit_list_insert: return the new commit list entry
[git/git.git] / commit.c
1 #include "tag.h"
2 #include "commit.h"
3 #include "cache.h"
4
5 const char *commit_type = "commit";
6
7 static struct commit *check_commit(struct object *obj, unsigned char *sha1)
8 {
9 if (obj->type != commit_type) {
10 error("Object %s is a %s, not a commit",
11 sha1_to_hex(sha1), obj->type);
12 return NULL;
13 }
14 return (struct commit *) obj;
15 }
16
17 struct commit *lookup_commit_reference(unsigned char *sha1)
18 {
19 struct object *obj = parse_object(sha1);
20
21 if (!obj)
22 return NULL;
23 if (obj->type == tag_type)
24 obj = ((struct tag *)obj)->tagged;
25 return check_commit(obj, sha1);
26 }
27
28 struct commit *lookup_commit(unsigned char *sha1)
29 {
30 struct object *obj = lookup_object(sha1);
31 if (!obj) {
32 struct commit *ret = xmalloc(sizeof(struct commit));
33 memset(ret, 0, sizeof(struct commit));
34 created_object(sha1, &ret->object);
35 ret->object.type = commit_type;
36 return ret;
37 }
38 if (!obj->type)
39 obj->type = commit_type;
40 return check_commit(obj, sha1);
41 }
42
43 static unsigned long parse_commit_date(const char *buf)
44 {
45 unsigned long date;
46
47 if (memcmp(buf, "author", 6))
48 return 0;
49 while (*buf++ != '\n')
50 /* nada */;
51 if (memcmp(buf, "committer", 9))
52 return 0;
53 while (*buf++ != '>')
54 /* nada */;
55 date = strtoul(buf, NULL, 10);
56 if (date == ULONG_MAX)
57 date = 0;
58 return date;
59 }
60
61 int parse_commit_buffer(struct commit *item, void *buffer, unsigned long size)
62 {
63 void *bufptr = buffer;
64 unsigned char parent[20];
65
66 if (item->object.parsed)
67 return 0;
68 item->object.parsed = 1;
69 get_sha1_hex(bufptr + 5, parent);
70 item->tree = lookup_tree(parent);
71 if (item->tree)
72 add_ref(&item->object, &item->tree->object);
73 bufptr += 46; /* "tree " + "hex sha1" + "\n" */
74 while (!memcmp(bufptr, "parent ", 7) &&
75 !get_sha1_hex(bufptr + 7, parent)) {
76 struct commit *new_parent = lookup_commit(parent);
77 if (new_parent) {
78 commit_list_insert(new_parent, &item->parents);
79 add_ref(&item->object, &new_parent->object);
80 }
81 bufptr += 48;
82 }
83 item->date = parse_commit_date(bufptr);
84 return 0;
85 }
86
87 int parse_commit(struct commit *item)
88 {
89 char type[20];
90 void *buffer;
91 unsigned long size;
92 int ret;
93
94 if (item->object.parsed)
95 return 0;
96 buffer = read_sha1_file(item->object.sha1, type, &size);
97 if (!buffer)
98 return error("Could not read %s",
99 sha1_to_hex(item->object.sha1));
100 if (strcmp(type, commit_type)) {
101 free(buffer);
102 return error("Object %s not a commit",
103 sha1_to_hex(item->object.sha1));
104 }
105 ret = parse_commit_buffer(item, buffer, size);
106 if (!ret) {
107 item->buffer = buffer;
108 return 0;
109 }
110 free(buffer);
111 return ret;
112 }
113
114 struct commit_list *commit_list_insert(struct commit *item, struct commit_list **list_p)
115 {
116 struct commit_list *new_list = xmalloc(sizeof(struct commit_list));
117 new_list->item = item;
118 new_list->next = *list_p;
119 *list_p = new_list;
120 return new_list;
121 }
122
123 void free_commit_list(struct commit_list *list)
124 {
125 while (list) {
126 struct commit_list *temp = list;
127 list = temp->next;
128 free(temp);
129 }
130 }
131
132 static void insert_by_date(struct commit_list **list, struct commit *item)
133 {
134 struct commit_list **pp = list;
135 struct commit_list *p;
136 while ((p = *pp) != NULL) {
137 if (p->item->date < item->date) {
138 break;
139 }
140 pp = &p->next;
141 }
142 commit_list_insert(item, pp);
143 }
144
145
146 void sort_by_date(struct commit_list **list)
147 {
148 struct commit_list *ret = NULL;
149 while (*list) {
150 insert_by_date(&ret, (*list)->item);
151 *list = (*list)->next;
152 }
153 *list = ret;
154 }
155
156 struct commit *pop_most_recent_commit(struct commit_list **list,
157 unsigned int mark)
158 {
159 struct commit *ret = (*list)->item;
160 struct commit_list *parents = ret->parents;
161 struct commit_list *old = *list;
162
163 *list = (*list)->next;
164 free(old);
165
166 while (parents) {
167 struct commit *commit = parents->item;
168 parse_commit(commit);
169 if (!(commit->object.flags & mark)) {
170 commit->object.flags |= mark;
171 insert_by_date(list, commit);
172 }
173 parents = parents->next;
174 }
175 return ret;
176 }