2 #include "string-list.h"
4 #include "xdiff/xdiff.h"
5 #include "xdiff-interface.h"
7 /* if rerere_enabled == -1, fall back to detection of .git/rr-cache */
8 static int rerere_enabled = -1;
10 /* automatically update cleanly resolved paths to the index */
11 static int rerere_autoupdate;
13 static char *merge_rr_path;
15 static const char *rr_path(const char *name, const char *file)
17 return git_path("rr-cache/%s/%s", name, file);
20 static int has_resolution(const char *name)
23 return !stat(rr_path(name, "postimage"), &st);
26 static void read_rr(struct string_list *rr)
28 unsigned char sha1[20];
30 FILE *in = fopen(merge_rr_path, "r");
33 while (fread(buf, 40, 1, in) == 1) {
36 if (get_sha1_hex(buf, sha1))
37 die("corrupt MERGE_RR");
40 if (fgetc(in) != '\t')
41 die("corrupt MERGE_RR");
42 for (i = 0; i < sizeof(buf) && (buf[i] = fgetc(in)); i++)
45 die("filename too long");
46 string_list_insert(buf, rr)->util = name;
51 static struct lock_file write_lock;
53 static int write_rr(struct string_list *rr, int out_fd)
56 for (i = 0; i < rr->nr; i++) {
59 if (!rr->items[i].util)
61 path = rr->items[i].string;
62 length = strlen(path) + 1;
63 if (write_in_full(out_fd, rr->items[i].util, 40) != 40 ||
64 write_in_full(out_fd, "\t", 1) != 1 ||
65 write_in_full(out_fd, path, length) != length)
66 die("unable to write rerere record");
68 if (commit_lock_file(&write_lock) != 0)
69 die("unable to write rerere record");
73 static int handle_file(const char *path,
74 unsigned char *sha1, const char *output)
80 RR_CONTEXT = 0, RR_SIDE_1, RR_SIDE_2, RR_ORIGINAL,
82 struct strbuf one, two;
83 FILE *f = fopen(path, "r");
87 return error("Could not open %s", path);
90 out = fopen(output, "w");
93 return error("Could not write %s", output);
100 strbuf_init(&one, 0);
101 strbuf_init(&two, 0);
102 while (fgets(buf, sizeof(buf), f)) {
103 if (!prefixcmp(buf, "<<<<<<< ")) {
104 if (hunk != RR_CONTEXT)
107 } else if (!prefixcmp(buf, "|||||||") && isspace(buf[7])) {
108 if (hunk != RR_SIDE_1)
111 } else if (!prefixcmp(buf, "=======") && isspace(buf[7])) {
112 if (hunk != RR_SIDE_1 && hunk != RR_ORIGINAL)
115 } else if (!prefixcmp(buf, ">>>>>>> ")) {
116 if (hunk != RR_SIDE_2)
118 if (strbuf_cmp(&one, &two) > 0)
119 strbuf_swap(&one, &two);
123 fputs("<<<<<<<\n", out);
124 fwrite(one.buf, one.len, 1, out);
125 fputs("=======\n", out);
126 fwrite(two.buf, two.len, 1, out);
127 fputs(">>>>>>>\n", out);
130 SHA1_Update(&ctx, one.buf ? one.buf : "",
132 SHA1_Update(&ctx, two.buf ? two.buf : "",
137 } else if (hunk == RR_SIDE_1)
138 strbuf_addstr(&one, buf);
139 else if (hunk == RR_ORIGINAL)
141 else if (hunk == RR_SIDE_2)
142 strbuf_addstr(&two, buf);
147 hunk = 99; /* force error exit */
150 strbuf_release(&one);
151 strbuf_release(&two);
157 SHA1_Final(sha1, &ctx);
158 if (hunk != RR_CONTEXT) {
161 return error("Could not parse conflict hunks in %s", path);
166 static int find_conflict(struct string_list *conflict)
169 if (read_cache() < 0)
170 return error("Could not read index");
171 for (i = 0; i+1 < active_nr; i++) {
172 struct cache_entry *e2 = active_cache[i];
173 struct cache_entry *e3 = active_cache[i+1];
174 if (ce_stage(e2) == 2 &&
176 ce_same_name(e2, e3) &&
177 S_ISREG(e2->ce_mode) &&
178 S_ISREG(e3->ce_mode)) {
179 string_list_insert((const char *)e2->name, conflict);
180 i++; /* skip over both #2 and #3 */
186 static int merge(const char *name, const char *path)
189 mmfile_t cur, base, other;
190 mmbuffer_t result = {NULL, 0};
191 xpparam_t xpp = {XDF_NEED_MINIMAL};
193 if (handle_file(path, NULL, rr_path(name, "thisimage")) < 0)
196 if (read_mmfile(&cur, rr_path(name, "thisimage")) ||
197 read_mmfile(&base, rr_path(name, "preimage")) ||
198 read_mmfile(&other, rr_path(name, "postimage")))
200 ret = xdl_merge(&base, &cur, "", &other, "",
201 &xpp, XDL_MERGE_ZEALOUS, &result);
203 FILE *f = fopen(path, "w");
205 return error("Could not write to %s", path);
206 fwrite(result.ptr, result.size, 1, f);
218 static struct lock_file index_lock;
220 static int update_paths(struct string_list *update)
223 int fd = hold_locked_index(&index_lock, 0);
229 for (i = 0; i < update->nr; i++) {
230 struct string_list_item *item = &update->items[i];
231 if (add_file_to_cache(item->string, ADD_CACHE_IGNORE_ERRORS))
235 if (!status && active_cache_changed) {
236 if (write_cache(fd, active_cache, active_nr) ||
237 commit_locked_index(&index_lock))
238 die("Unable to write new index file");
240 rollback_lock_file(&index_lock);
244 static int do_plain_rerere(struct string_list *rr, int fd)
246 struct string_list conflict = { NULL, 0, 0, 1 };
247 struct string_list update = { NULL, 0, 0, 1 };
250 find_conflict(&conflict);
253 * MERGE_RR records paths with conflicts immediately after merge
254 * failed. Some of the conflicted paths might have been hand resolved
255 * in the working tree since then, but the initial run would catch all
256 * and register their preimages.
259 for (i = 0; i < conflict.nr; i++) {
260 const char *path = conflict.items[i].string;
261 if (!string_list_has_string(rr, path)) {
262 unsigned char sha1[20];
265 ret = handle_file(path, sha1, NULL);
268 hex = xstrdup(sha1_to_hex(sha1));
269 string_list_insert(path, rr)->util = hex;
270 if (mkdir(git_path("rr-cache/%s", hex), 0755))
272 handle_file(path, NULL, rr_path(hex, "preimage"));
273 fprintf(stderr, "Recorded preimage for '%s'\n", path);
278 * Now some of the paths that had conflicts earlier might have been
279 * hand resolved. Others may be similar to a conflict already that
280 * was resolved before.
283 for (i = 0; i < rr->nr; i++) {
285 const char *path = rr->items[i].string;
286 const char *name = (const char *)rr->items[i].util;
288 if (has_resolution(name)) {
289 if (!merge(name, path)) {
290 if (rerere_autoupdate)
291 string_list_insert(path, &update);
293 "%s '%s' using previous resolution.\n",
295 ? "Staged" : "Resolved",
301 /* Let's see if we have resolved it. */
302 ret = handle_file(path, NULL, NULL);
306 fprintf(stderr, "Recorded resolution for '%s'.\n", path);
307 copy_file(rr_path(name, "postimage"), path, 0666);
309 rr->items[i].util = NULL;
313 update_paths(&update);
315 return write_rr(rr, fd);
318 static int git_rerere_config(const char *var, const char *value, void *cb)
320 if (!strcmp(var, "rerere.enabled"))
321 rerere_enabled = git_config_bool(var, value);
322 else if (!strcmp(var, "rerere.autoupdate"))
323 rerere_autoupdate = git_config_bool(var, value);
325 return git_default_config(var, value, cb);
329 static int is_rerere_enabled(void)
331 const char *rr_cache;
337 rr_cache = git_path("rr-cache");
338 rr_cache_exists = is_directory(rr_cache);
339 if (rerere_enabled < 0)
340 return rr_cache_exists;
342 if (!rr_cache_exists &&
343 (mkdir(rr_cache, 0777) || adjust_shared_perm(rr_cache)))
344 die("Could not create directory %s", rr_cache);
348 int setup_rerere(struct string_list *merge_rr)
352 git_config(git_rerere_config, NULL);
353 if (!is_rerere_enabled())
356 merge_rr_path = xstrdup(git_path("MERGE_RR"));
357 fd = hold_lock_file_for_update(&write_lock, merge_rr_path, 1);
364 struct string_list merge_rr = { NULL, 0, 0, 1 };
367 fd = setup_rerere(&merge_rr);
370 return do_plain_rerere(&merge_rr, fd);