Add "rev-list" program that uses the new time-based commit listing.
[git/git.git] / commit.c
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1#include "commit.h"
2#include "cache.h"
3#include <string.h>
b2c00718 4#include <limits.h>
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5
6const char *commit_type = "commit";
7
8struct 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 return ret;
16 }
17 if (obj->parsed && obj->type != commit_type) {
18 error("Object %s is a %s, not a commit",
19 sha1_to_hex(sha1), obj->type);
20 return NULL;
21 }
22 return (struct commit *) obj;
23}
24
25static unsigned long parse_commit_date(const char *buf)
26{
27 unsigned long date;
28
29 if (memcmp(buf, "author", 6))
30 return 0;
31 while (*buf++ != '\n')
32 /* nada */;
33 if (memcmp(buf, "committer", 9))
34 return 0;
35 while (*buf++ != '>')
36 /* nada */;
37 date = strtoul(buf, NULL, 10);
38 if (date == ULONG_MAX)
39 date = 0;
40 return date;
41}
42
43int parse_commit(struct commit *item)
44{
45 char type[20];
46 void * buffer, *bufptr;
47 unsigned long size;
48 unsigned char parent[20];
49 if (item->object.parsed)
50 return 0;
51 item->object.parsed = 1;
52 buffer = bufptr = read_sha1_file(item->object.sha1, type, &size);
53 if (!buffer)
54 return error("Could not read %s",
55 sha1_to_hex(item->object.sha1));
56 if (strcmp(type, commit_type))
57 return error("Object %s not a commit",
58 sha1_to_hex(item->object.sha1));
59 item->object.type = commit_type;
60 get_sha1_hex(bufptr + 5, parent);
61 item->tree = lookup_tree(parent);
62 add_ref(&item->object, &item->tree->object);
63 bufptr += 46; /* "tree " + "hex sha1" + "\n" */
64 while (!memcmp(bufptr, "parent ", 7) &&
65 !get_sha1_hex(bufptr + 7, parent)) {
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66 struct commit *new_parent = lookup_commit(parent);
67 commit_list_insert(new_parent, &item->parents);
68 add_ref(&item->object, &new_parent->object);
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69 bufptr += 48;
70 }
71 item->date = parse_commit_date(bufptr);
72 free(buffer);
73 return 0;
74}
75
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76void commit_list_insert(struct commit *item, struct commit_list **list_p)
77{
78 struct commit_list *new_list = malloc(sizeof(struct commit_list));
79 new_list->item = item;
80 new_list->next = *list_p;
81 *list_p = new_list;
82}
83
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84void free_commit_list(struct commit_list *list)
85{
86 while (list) {
87 struct commit_list *temp = list;
88 list = temp->next;
89 free(temp);
90 }
91}
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92
93static void insert_by_date(struct commit_list **list, struct commit *item)
94{
95 struct commit_list **pp = list;
96 struct commit_list *p;
97 while ((p = *pp) != NULL) {
98 if (p->item->date < item->date) {
99 break;
100 }
101 pp = &p->next;
102 }
103 commit_list_insert(item, pp);
104}
105
106
107void sort_by_date(struct commit_list **list)
108{
109 struct commit_list *ret = NULL;
110 while (*list) {
111 insert_by_date(&ret, (*list)->item);
112 *list = (*list)->next;
113 }
114 *list = ret;
115}
116
117struct commit *pop_most_recent_commit(struct commit_list **list)
118{
119 struct commit *ret = (*list)->item;
120 struct commit_list *parents = ret->parents;
121 struct commit_list *old = *list;
122
123 *list = (*list)->next;
124 free(old);
125
126 while (parents) {
127 parse_commit(parents->item);
128 insert_by_date(list, parents->item);
129 parents = parents->next;
130 }
131 return ret;
132}