]>
Commit | Line | Data |
---|---|---|
492e0759 | 1 | #include "cache.h" |
1b0c7174 | 2 | #include "tree-walk.h" |
492e0759 LT |
3 | |
4 | static const char merge_tree_usage[] = "git-merge-tree <base-tree> <branch1> <branch2>"; | |
5 | static int resolve_directories = 1; | |
6 | ||
7 | static void merge_trees(struct tree_desc t[3], const char *base); | |
8 | ||
492e0759 LT |
9 | /* An empty entry never compares same, not even to another empty entry */ |
10 | static int same_entry(struct name_entry *a, struct name_entry *b) | |
11 | { | |
12 | return a->sha1 && | |
13 | b->sha1 && | |
14 | !memcmp(a->sha1, b->sha1, 20) && | |
15 | a->mode == b->mode; | |
16 | } | |
17 | ||
01df5297 | 18 | static const char *sha1_to_hex_zero(const unsigned char *sha1) |
492e0759 | 19 | { |
01df5297 LT |
20 | if (sha1) |
21 | return sha1_to_hex(sha1); | |
22 | return "0000000000000000000000000000000000000000"; | |
23 | } | |
24 | ||
25 | static void resolve(const char *base, struct name_entry *branch1, struct name_entry *result) | |
26 | { | |
01df5297 LT |
27 | /* If it's already branch1, don't bother showing it */ |
28 | if (!branch1) | |
29 | return; | |
01df5297 LT |
30 | |
31 | printf("0 %06o->%06o %s->%s %s%s\n", | |
32 | branch1->mode, result->mode, | |
dcb3450f LT |
33 | sha1_to_hex_zero(branch1->sha1), |
34 | sha1_to_hex_zero(result->sha1), | |
01df5297 | 35 | base, result->path); |
492e0759 LT |
36 | } |
37 | ||
38 | static int unresolved_directory(const char *base, struct name_entry n[3]) | |
39 | { | |
40 | int baselen; | |
41 | char *newbase; | |
42 | struct name_entry *p; | |
43 | struct tree_desc t[3]; | |
44 | void *buf0, *buf1, *buf2; | |
45 | ||
46 | if (!resolve_directories) | |
47 | return 0; | |
48 | p = n; | |
49 | if (!p->mode) { | |
50 | p++; | |
51 | if (!p->mode) | |
52 | p++; | |
53 | } | |
54 | if (!S_ISDIR(p->mode)) | |
55 | return 0; | |
56 | baselen = strlen(base); | |
57 | newbase = xmalloc(baselen + p->pathlen + 2); | |
58 | memcpy(newbase, base, baselen); | |
59 | memcpy(newbase + baselen, p->path, p->pathlen); | |
60 | memcpy(newbase + baselen + p->pathlen, "/", 2); | |
61 | ||
62 | buf0 = fill_tree_descriptor(t+0, n[0].sha1); | |
63 | buf1 = fill_tree_descriptor(t+1, n[1].sha1); | |
64 | buf2 = fill_tree_descriptor(t+2, n[2].sha1); | |
65 | merge_trees(t, newbase); | |
66 | ||
67 | free(buf0); | |
68 | free(buf1); | |
69 | free(buf2); | |
70 | free(newbase); | |
71 | return 1; | |
72 | } | |
73 | ||
74 | static void unresolved(const char *base, struct name_entry n[3]) | |
75 | { | |
76 | if (unresolved_directory(base, n)) | |
77 | return; | |
01df5297 LT |
78 | if (n[0].sha1) |
79 | printf("1 %06o %s %s%s\n", n[0].mode, sha1_to_hex(n[0].sha1), base, n[0].path); | |
80 | if (n[1].sha1) | |
81 | printf("2 %06o %s %s%s\n", n[1].mode, sha1_to_hex(n[1].sha1), base, n[1].path); | |
82 | if (n[2].sha1) | |
83 | printf("3 %06o %s %s%s\n", n[2].mode, sha1_to_hex(n[2].sha1), base, n[2].path); | |
492e0759 LT |
84 | } |
85 | ||
164dcb97 LT |
86 | /* |
87 | * Merge two trees together (t[1] and t[2]), using a common base (t[0]) | |
88 | * as the origin. | |
89 | * | |
90 | * This walks the (sorted) trees in lock-step, checking every possible | |
91 | * name. Note that directories automatically sort differently from other | |
92 | * files (see "base_name_compare"), so you'll never see file/directory | |
93 | * conflicts, because they won't ever compare the same. | |
94 | * | |
95 | * IOW, if a directory changes to a filename, it will automatically be | |
96 | * seen as the directory going away, and the filename being created. | |
97 | * | |
98 | * Think of this as a three-way diff. | |
99 | * | |
100 | * The output will be either: | |
101 | * - successful merge | |
102 | * "0 mode sha1 filename" | |
103 | * NOTE NOTE NOTE! FIXME! We really really need to walk the index | |
104 | * in parallel with this too! | |
105 | * | |
106 | * - conflict: | |
107 | * "1 mode sha1 filename" | |
108 | * "2 mode sha1 filename" | |
109 | * "3 mode sha1 filename" | |
110 | * where not all of the 1/2/3 lines may exist, of course. | |
111 | * | |
112 | * The successful merge rules are the same as for the three-way merge | |
113 | * in git-read-tree. | |
114 | */ | |
115 | static void threeway_callback(int n, unsigned long mask, struct name_entry *entry, const char *base) | |
116 | { | |
117 | /* Same in both? */ | |
118 | if (same_entry(entry+1, entry+2)) { | |
119 | if (entry[0].sha1) { | |
120 | resolve(base, NULL, entry+1); | |
121 | return; | |
492e0759 | 122 | } |
164dcb97 | 123 | } |
492e0759 | 124 | |
164dcb97 LT |
125 | if (same_entry(entry+0, entry+1)) { |
126 | if (entry[2].sha1 && !S_ISDIR(entry[2].mode)) { | |
127 | resolve(base, entry+1, entry+2); | |
128 | return; | |
492e0759 | 129 | } |
164dcb97 | 130 | } |
492e0759 | 131 | |
164dcb97 LT |
132 | if (same_entry(entry+0, entry+2)) { |
133 | if (entry[1].sha1 && !S_ISDIR(entry[1].mode)) { | |
134 | resolve(base, NULL, entry+1); | |
135 | return; | |
492e0759 | 136 | } |
492e0759 | 137 | } |
164dcb97 LT |
138 | |
139 | unresolved(base, entry); | |
140 | } | |
141 | ||
142 | static void merge_trees(struct tree_desc t[3], const char *base) | |
143 | { | |
144 | traverse_trees(3, t, base, threeway_callback); | |
492e0759 LT |
145 | } |
146 | ||
147 | static void *get_tree_descriptor(struct tree_desc *desc, const char *rev) | |
148 | { | |
149 | unsigned char sha1[20]; | |
150 | void *buf; | |
151 | ||
31fff305 | 152 | if (get_sha1(rev, sha1)) |
492e0759 LT |
153 | die("unknown rev %s", rev); |
154 | buf = fill_tree_descriptor(desc, sha1); | |
155 | if (!buf) | |
156 | die("%s is not a tree", rev); | |
157 | return buf; | |
158 | } | |
159 | ||
160 | int main(int argc, char **argv) | |
161 | { | |
162 | struct tree_desc t[3]; | |
163 | void *buf1, *buf2, *buf3; | |
164 | ||
165 | if (argc < 4) | |
166 | usage(merge_tree_usage); | |
167 | ||
168 | buf1 = get_tree_descriptor(t+0, argv[1]); | |
169 | buf2 = get_tree_descriptor(t+1, argv[2]); | |
170 | buf3 = get_tree_descriptor(t+2, argv[3]); | |
171 | merge_trees(t, ""); | |
172 | free(buf1); | |
173 | free(buf2); | |
174 | free(buf3); | |
175 | return 0; | |
176 | } |