1 #define USE_THE_INDEX_COMPATIBILITY_MACROS
4 #include "xdiff-interface.h"
5 #include "object-store.h"
6 #include "repository.h"
9 #include "merge-blobs.h"
11 static const char merge_tree_usage
[] = "git merge-tree <base-tree> <branch1> <branch2>";
14 struct merge_list
*next
;
15 struct merge_list
*link
; /* other stages for this object */
17 unsigned int stage
: 2;
23 static struct merge_list
*merge_result
, **merge_result_end
= &merge_result
;
25 static void add_merge_entry(struct merge_list
*entry
)
27 *merge_result_end
= entry
;
28 merge_result_end
= &entry
->next
;
31 static void merge_trees(struct tree_desc t
[3], const char *base
);
33 static const char *explanation(struct merge_list
*entry
)
35 switch (entry
->stage
) {
39 return "added in remote";
42 return "added in both";
43 return "added in local";
49 return "removed in both";
52 return "changed in both";
54 if (entry
->stage
== 3)
55 return "removed in local";
56 return "removed in remote";
59 static void *result(struct merge_list
*entry
, unsigned long *size
)
61 enum object_type type
;
62 struct blob
*base
, *our
, *their
;
63 const char *path
= entry
->path
;
66 return read_object_file(&entry
->blob
->object
.oid
, &type
, size
);
68 if (entry
->stage
== 1) {
73 if (entry
&& entry
->stage
== 2) {
80 return merge_blobs(the_repository
->index
, path
,
81 base
, our
, their
, size
);
84 static void *origin(struct merge_list
*entry
, unsigned long *size
)
86 enum object_type type
;
88 if (entry
->stage
== 2)
89 return read_object_file(&entry
->blob
->object
.oid
,
96 static int show_outf(void *priv_
, mmbuffer_t
*mb
, int nbuf
)
99 for (i
= 0; i
< nbuf
; i
++)
100 printf("%.*s", (int) mb
[i
].size
, mb
[i
].ptr
);
104 static void show_diff(struct merge_list
*entry
)
113 memset(&xecfg
, 0, sizeof(xecfg
));
116 ecb
.out_line
= show_outf
;
119 src
.ptr
= origin(entry
, &size
);
123 dst
.ptr
= result(entry
, &size
);
127 if (xdi_diff(&src
, &dst
, &xpp
, &xecfg
, &ecb
))
128 die("unable to generate diff");
133 static void show_result_list(struct merge_list
*entry
)
135 printf("%s\n", explanation(entry
));
137 struct merge_list
*link
= entry
->link
;
138 static const char *desc
[4] = { "result", "base", "our", "their" };
139 printf(" %-6s %o %s %s\n", desc
[entry
->stage
], entry
->mode
, oid_to_hex(&entry
->blob
->object
.oid
), entry
->path
);
144 static void show_result(void)
146 struct merge_list
*walk
;
150 show_result_list(walk
);
156 /* An empty entry never compares same, not even to another empty entry */
157 static int same_entry(struct name_entry
*a
, struct name_entry
*b
)
161 oideq(a
->oid
, b
->oid
) &&
165 static int both_empty(struct name_entry
*a
, struct name_entry
*b
)
167 return !(a
->oid
|| b
->oid
);
170 static struct merge_list
*create_entry(unsigned stage
, unsigned mode
, const struct object_id
*oid
, const char *path
)
172 struct merge_list
*res
= xcalloc(1, sizeof(*res
));
177 res
->blob
= lookup_blob(the_repository
, oid
);
181 static char *traverse_path(const struct traverse_info
*info
, const struct name_entry
*n
)
183 char *path
= xmallocz(traverse_path_len(info
, n
));
184 return make_traverse_path(path
, info
, n
);
187 static void resolve(const struct traverse_info
*info
, struct name_entry
*ours
, struct name_entry
*result
)
189 struct merge_list
*orig
, *final
;
192 /* If it's already ours, don't bother showing it */
196 path
= traverse_path(info
, result
);
197 orig
= create_entry(2, ours
->mode
, ours
->oid
, path
);
198 final
= create_entry(0, result
->mode
, result
->oid
, path
);
202 add_merge_entry(final
);
205 static void unresolved_directory(const struct traverse_info
*info
,
206 struct name_entry n
[3])
209 struct name_entry
*p
;
210 struct tree_desc t
[3];
211 void *buf0
, *buf1
, *buf2
;
213 for (p
= n
; p
< n
+ 3; p
++) {
214 if (p
->mode
&& S_ISDIR(p
->mode
))
218 return; /* there is no tree here */
220 newbase
= traverse_path(info
, p
);
222 #define ENTRY_OID(e) (((e)->mode && S_ISDIR((e)->mode)) ? (e)->oid : NULL)
223 buf0
= fill_tree_descriptor(t
+ 0, ENTRY_OID(n
+ 0));
224 buf1
= fill_tree_descriptor(t
+ 1, ENTRY_OID(n
+ 1));
225 buf2
= fill_tree_descriptor(t
+ 2, ENTRY_OID(n
+ 2));
228 merge_trees(t
, newbase
);
237 static struct merge_list
*link_entry(unsigned stage
, const struct traverse_info
*info
, struct name_entry
*n
, struct merge_list
*entry
)
240 struct merge_list
*link
;
247 path
= traverse_path(info
, n
);
248 link
= create_entry(stage
, n
->mode
, n
->oid
, path
);
253 static void unresolved(const struct traverse_info
*info
, struct name_entry n
[3])
255 struct merge_list
*entry
= NULL
;
257 unsigned dirmask
= 0, mask
= 0;
259 for (i
= 0; i
< 3; i
++) {
262 * Treat missing entries as directories so that we return
263 * after unresolved_directory has handled this.
265 if (!n
[i
].mode
|| S_ISDIR(n
[i
].mode
))
269 unresolved_directory(info
, n
);
274 if (n
[2].mode
&& !S_ISDIR(n
[2].mode
))
275 entry
= link_entry(3, info
, n
+ 2, entry
);
276 if (n
[1].mode
&& !S_ISDIR(n
[1].mode
))
277 entry
= link_entry(2, info
, n
+ 1, entry
);
278 if (n
[0].mode
&& !S_ISDIR(n
[0].mode
))
279 entry
= link_entry(1, info
, n
+ 0, entry
);
281 add_merge_entry(entry
);
285 * Merge two trees together (t[1] and t[2]), using a common base (t[0])
288 * This walks the (sorted) trees in lock-step, checking every possible
289 * name. Note that directories automatically sort differently from other
290 * files (see "base_name_compare"), so you'll never see file/directory
291 * conflicts, because they won't ever compare the same.
293 * IOW, if a directory changes to a filename, it will automatically be
294 * seen as the directory going away, and the filename being created.
296 * Think of this as a three-way diff.
298 * The output will be either:
300 * "0 mode sha1 filename"
301 * NOTE NOTE NOTE! FIXME! We really really need to walk the index
302 * in parallel with this too!
305 * "1 mode sha1 filename"
306 * "2 mode sha1 filename"
307 * "3 mode sha1 filename"
308 * where not all of the 1/2/3 lines may exist, of course.
310 * The successful merge rules are the same as for the three-way merge
313 static int threeway_callback(int n
, unsigned long mask
, unsigned long dirmask
, struct name_entry
*entry
, struct traverse_info
*info
)
316 if (same_entry(entry
+1, entry
+2) || both_empty(entry
+1, entry
+2)) {
317 /* Modified, added or removed identically */
318 resolve(info
, NULL
, entry
+1);
322 if (same_entry(entry
+0, entry
+1)) {
323 if (entry
[2].oid
&& !S_ISDIR(entry
[2].mode
)) {
324 /* We did not touch, they modified -- take theirs */
325 resolve(info
, entry
+1, entry
+2);
329 * If we did not touch a directory but they made it
330 * into a file, we fall through and unresolved()
331 * recurses down. Likewise for the opposite case.
335 if (same_entry(entry
+0, entry
+2) || both_empty(entry
+0, entry
+2)) {
336 /* We added, modified or removed, they did not touch -- take ours */
337 resolve(info
, NULL
, entry
+1);
341 unresolved(info
, entry
);
345 static void merge_trees(struct tree_desc t
[3], const char *base
)
347 struct traverse_info info
;
349 setup_traverse_info(&info
, base
);
350 info
.fn
= threeway_callback
;
351 traverse_trees(3, t
, &info
);
354 static void *get_tree_descriptor(struct tree_desc
*desc
, const char *rev
)
356 struct object_id oid
;
359 if (get_oid(rev
, &oid
))
360 die("unknown rev %s", rev
);
361 buf
= fill_tree_descriptor(desc
, &oid
);
363 die("%s is not a tree", rev
);
367 int cmd_merge_tree(int argc
, const char **argv
, const char *prefix
)
369 struct tree_desc t
[3];
370 void *buf1
, *buf2
, *buf3
;
373 usage(merge_tree_usage
);
375 buf1
= get_tree_descriptor(t
+0, argv
[1]);
376 buf2
= get_tree_descriptor(t
+1, argv
[2]);
377 buf3
= get_tree_descriptor(t
+2, argv
[3]);