Andrew's git / gitweb.git / rerere.c
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rerere.con commit Update draft release notes to 2.2 (fbecd99)
   1#include "cache.h"
   2#include "lockfile.h"
   3#include "string-list.h"
   4#include "rerere.h"
   5#include "xdiff-interface.h"
   6#include "dir.h"
   7#include "resolve-undo.h"
   8#include "ll-merge.h"
   9#include "attr.h"
  10#include "pathspec.h"
  11
  12#define RESOLVED 0
  13#define PUNTED 1
  14#define THREE_STAGED 2
  15void *RERERE_RESOLVED = &RERERE_RESOLVED;
  16
  17/* if rerere_enabled == -1, fall back to detection of .git/rr-cache */
  18static int rerere_enabled = -1;
  19
  20/* automatically update cleanly resolved paths to the index */
  21static int rerere_autoupdate;
  22
  23static char *merge_rr_path;
  24
  25const char *rerere_path(const char *hex, const char *file)
  26{
  27        return git_path("rr-cache/%s/%s", hex, file);
  28}
  29
  30static int has_rerere_resolution(const char *hex)
  31{
  32        struct stat st;
  33        return !stat(rerere_path(hex, "postimage"), &st);
  34}
  35
  36static void read_rr(struct string_list *rr)
  37{
  38        unsigned char sha1[20];
  39        char buf[PATH_MAX];
  40        FILE *in = fopen(merge_rr_path, "r");
  41        if (!in)
  42                return;
  43        while (fread(buf, 40, 1, in) == 1) {
  44                int i;
  45                char *name;
  46                if (get_sha1_hex(buf, sha1))
  47                        die("corrupt MERGE_RR");
  48                buf[40] = '\0';
  49                name = xstrdup(buf);
  50                if (fgetc(in) != '\t')
  51                        die("corrupt MERGE_RR");
  52                for (i = 0; i < sizeof(buf); i++) {
  53                        int c = fgetc(in);
  54                        if (c < 0)
  55                                die("corrupt MERGE_RR");
  56                        buf[i] = c;
  57                        if (c == 0)
  58                                 break;
  59                }
  60                if (i == sizeof(buf))
  61                        die("filename too long");
  62                string_list_insert(rr, buf)->util = name;
  63        }
  64        fclose(in);
  65}
  66
  67static struct lock_file write_lock;
  68
  69static int write_rr(struct string_list *rr, int out_fd)
  70{
  71        int i;
  72        for (i = 0; i < rr->nr; i++) {
  73                const char *path;
  74                int length;
  75                if (!rr->items[i].util)
  76                        continue;
  77                path = rr->items[i].string;
  78                length = strlen(path) + 1;
  79                if (write_in_full(out_fd, rr->items[i].util, 40) != 40 ||
  80                    write_str_in_full(out_fd, "\t") != 1 ||
  81                    write_in_full(out_fd, path, length) != length)
  82                        die("unable to write rerere record");
  83        }
  84        if (commit_lock_file(&write_lock) != 0)
  85                die("unable to write rerere record");
  86        return 0;
  87}
  88
  89static void ferr_write(const void *p, size_t count, FILE *fp, int *err)
  90{
  91        if (!count || *err)
  92                return;
  93        if (fwrite(p, count, 1, fp) != 1)
  94                *err = errno;
  95}
  96
  97static inline void ferr_puts(const char *s, FILE *fp, int *err)
  98{
  99        ferr_write(s, strlen(s), fp, err);
 100}
 101
 102struct rerere_io {
 103        int (*getline)(struct strbuf *, struct rerere_io *);
 104        FILE *output;
 105        int wrerror;
 106        /* some more stuff */
 107};
 108
 109static void rerere_io_putstr(const char *str, struct rerere_io *io)
 110{
 111        if (io->output)
 112                ferr_puts(str, io->output, &io->wrerror);
 113}
 114
 115static void rerere_io_putconflict(int ch, int size, struct rerere_io *io)
 116{
 117        char buf[64];
 118
 119        while (size) {
 120                if (size < sizeof(buf) - 2) {
 121                        memset(buf, ch, size);
 122                        buf[size] = '\n';
 123                        buf[size + 1] = '\0';
 124                        size = 0;
 125                } else {
 126                        int sz = sizeof(buf) - 1;
 127                        if (size <= sz)
 128                                sz -= (sz - size) + 1;
 129                        memset(buf, ch, sz);
 130                        buf[sz] = '\0';
 131                        size -= sz;
 132                }
 133                rerere_io_putstr(buf, io);
 134        }
 135}
 136
 137static void rerere_io_putmem(const char *mem, size_t sz, struct rerere_io *io)
 138{
 139        if (io->output)
 140                ferr_write(mem, sz, io->output, &io->wrerror);
 141}
 142
 143struct rerere_io_file {
 144        struct rerere_io io;
 145        FILE *input;
 146};
 147
 148static int rerere_file_getline(struct strbuf *sb, struct rerere_io *io_)
 149{
 150        struct rerere_io_file *io = (struct rerere_io_file *)io_;
 151        return strbuf_getwholeline(sb, io->input, '\n');
 152}
 153
 154static int is_cmarker(char *buf, int marker_char, int marker_size, int want_sp)
 155{
 156        while (marker_size--)
 157                if (*buf++ != marker_char)
 158                        return 0;
 159        if (want_sp && *buf != ' ')
 160                return 0;
 161        return isspace(*buf);
 162}
 163
 164static int handle_path(unsigned char *sha1, struct rerere_io *io, int marker_size)
 165{
 166        git_SHA_CTX ctx;
 167        int hunk_no = 0;
 168        enum {
 169                RR_CONTEXT = 0, RR_SIDE_1, RR_SIDE_2, RR_ORIGINAL
 170        } hunk = RR_CONTEXT;
 171        struct strbuf one = STRBUF_INIT, two = STRBUF_INIT;
 172        struct strbuf buf = STRBUF_INIT;
 173
 174        if (sha1)
 175                git_SHA1_Init(&ctx);
 176
 177        while (!io->getline(&buf, io)) {
 178                if (is_cmarker(buf.buf, '<', marker_size, 1)) {
 179                        if (hunk != RR_CONTEXT)
 180                                goto bad;
 181                        hunk = RR_SIDE_1;
 182                } else if (is_cmarker(buf.buf, '|', marker_size, 0)) {
 183                        if (hunk != RR_SIDE_1)
 184                                goto bad;
 185                        hunk = RR_ORIGINAL;
 186                } else if (is_cmarker(buf.buf, '=', marker_size, 0)) {
 187                        if (hunk != RR_SIDE_1 && hunk != RR_ORIGINAL)
 188                                goto bad;
 189                        hunk = RR_SIDE_2;
 190                } else if (is_cmarker(buf.buf, '>', marker_size, 1)) {
 191                        if (hunk != RR_SIDE_2)
 192                                goto bad;
 193                        if (strbuf_cmp(&one, &two) > 0)
 194                                strbuf_swap(&one, &two);
 195                        hunk_no++;
 196                        hunk = RR_CONTEXT;
 197                        rerere_io_putconflict('<', marker_size, io);
 198                        rerere_io_putmem(one.buf, one.len, io);
 199                        rerere_io_putconflict('=', marker_size, io);
 200                        rerere_io_putmem(two.buf, two.len, io);
 201                        rerere_io_putconflict('>', marker_size, io);
 202                        if (sha1) {
 203                                git_SHA1_Update(&ctx, one.buf ? one.buf : "",
 204                                            one.len + 1);
 205                                git_SHA1_Update(&ctx, two.buf ? two.buf : "",
 206                                            two.len + 1);
 207                        }
 208                        strbuf_reset(&one);
 209                        strbuf_reset(&two);
 210                } else if (hunk == RR_SIDE_1)
 211                        strbuf_addbuf(&one, &buf);
 212                else if (hunk == RR_ORIGINAL)
 213                        ; /* discard */
 214                else if (hunk == RR_SIDE_2)
 215                        strbuf_addbuf(&two, &buf);
 216                else
 217                        rerere_io_putstr(buf.buf, io);
 218                continue;
 219        bad:
 220                hunk = 99; /* force error exit */
 221                break;
 222        }
 223        strbuf_release(&one);
 224        strbuf_release(&two);
 225        strbuf_release(&buf);
 226
 227        if (sha1)
 228                git_SHA1_Final(sha1, &ctx);
 229        if (hunk != RR_CONTEXT)
 230                return -1;
 231        return hunk_no;
 232}
 233
 234static int handle_file(const char *path, unsigned char *sha1, const char *output)
 235{
 236        int hunk_no = 0;
 237        struct rerere_io_file io;
 238        int marker_size = ll_merge_marker_size(path);
 239
 240        memset(&io, 0, sizeof(io));
 241        io.io.getline = rerere_file_getline;
 242        io.input = fopen(path, "r");
 243        io.io.wrerror = 0;
 244        if (!io.input)
 245                return error("Could not open %s", path);
 246
 247        if (output) {
 248                io.io.output = fopen(output, "w");
 249                if (!io.io.output) {
 250                        fclose(io.input);
 251                        return error("Could not write %s", output);
 252                }
 253        }
 254
 255        hunk_no = handle_path(sha1, (struct rerere_io *)&io, marker_size);
 256
 257        fclose(io.input);
 258        if (io.io.wrerror)
 259                error("There were errors while writing %s (%s)",
 260                      path, strerror(io.io.wrerror));
 261        if (io.io.output && fclose(io.io.output))
 262                io.io.wrerror = error("Failed to flush %s: %s",
 263                                      path, strerror(errno));
 264
 265        if (hunk_no < 0) {
 266                if (output)
 267                        unlink_or_warn(output);
 268                return error("Could not parse conflict hunks in %s", path);
 269        }
 270        if (io.io.wrerror)
 271                return -1;
 272        return hunk_no;
 273}
 274
 275struct rerere_io_mem {
 276        struct rerere_io io;
 277        struct strbuf input;
 278};
 279
 280static int rerere_mem_getline(struct strbuf *sb, struct rerere_io *io_)
 281{
 282        struct rerere_io_mem *io = (struct rerere_io_mem *)io_;
 283        char *ep;
 284        size_t len;
 285
 286        strbuf_release(sb);
 287        if (!io->input.len)
 288                return -1;
 289        ep = memchr(io->input.buf, '\n', io->input.len);
 290        if (!ep)
 291                ep = io->input.buf + io->input.len;
 292        else if (*ep == '\n')
 293                ep++;
 294        len = ep - io->input.buf;
 295        strbuf_add(sb, io->input.buf, len);
 296        strbuf_remove(&io->input, 0, len);
 297        return 0;
 298}
 299
 300static int handle_cache(const char *path, unsigned char *sha1, const char *output)
 301{
 302        mmfile_t mmfile[3] = {{NULL}};
 303        mmbuffer_t result = {NULL, 0};
 304        const struct cache_entry *ce;
 305        int pos, len, i, hunk_no;
 306        struct rerere_io_mem io;
 307        int marker_size = ll_merge_marker_size(path);
 308
 309        /*
 310         * Reproduce the conflicted merge in-core
 311         */
 312        len = strlen(path);
 313        pos = cache_name_pos(path, len);
 314        if (0 <= pos)
 315                return -1;
 316        pos = -pos - 1;
 317
 318        for (i = 0; i < 3; i++) {
 319                enum object_type type;
 320                unsigned long size;
 321                int j;
 322
 323                if (active_nr <= pos)
 324                        break;
 325                ce = active_cache[pos++];
 326                if (ce_namelen(ce) != len || memcmp(ce->name, path, len))
 327                        continue;
 328                j = ce_stage(ce) - 1;
 329                mmfile[j].ptr = read_sha1_file(ce->sha1, &type, &size);
 330                mmfile[j].size = size;
 331        }
 332        for (i = 0; i < 3; i++) {
 333                if (!mmfile[i].ptr && !mmfile[i].size)
 334                        mmfile[i].ptr = xstrdup("");
 335        }
 336        /*
 337         * NEEDSWORK: handle conflicts from merges with
 338         * merge.renormalize set, too
 339         */
 340        ll_merge(&result, path, &mmfile[0], NULL,
 341                 &mmfile[1], "ours",
 342                 &mmfile[2], "theirs", NULL);
 343        for (i = 0; i < 3; i++)
 344                free(mmfile[i].ptr);
 345
 346        memset(&io, 0, sizeof(io));
 347        io.io.getline = rerere_mem_getline;
 348        if (output)
 349                io.io.output = fopen(output, "w");
 350        else
 351                io.io.output = NULL;
 352        strbuf_init(&io.input, 0);
 353        strbuf_attach(&io.input, result.ptr, result.size, result.size);
 354
 355        hunk_no = handle_path(sha1, (struct rerere_io *)&io, marker_size);
 356        strbuf_release(&io.input);
 357        if (io.io.output)
 358                fclose(io.io.output);
 359        return hunk_no;
 360}
 361
 362static int check_one_conflict(int i, int *type)
 363{
 364        const struct cache_entry *e = active_cache[i];
 365
 366        if (!ce_stage(e)) {
 367                *type = RESOLVED;
 368                return i + 1;
 369        }
 370
 371        *type = PUNTED;
 372        if (ce_stage(e) == 1) {
 373                if (active_nr <= ++i)
 374                        return i + 1;
 375        }
 376
 377        /* Only handle regular files with both stages #2 and #3 */
 378        if (i + 1 < active_nr) {
 379                const struct cache_entry *e2 = active_cache[i];
 380                const struct cache_entry *e3 = active_cache[i + 1];
 381                if (ce_stage(e2) == 2 &&
 382                    ce_stage(e3) == 3 &&
 383                    ce_same_name(e, e3) &&
 384                    S_ISREG(e2->ce_mode) &&
 385                    S_ISREG(e3->ce_mode))
 386                        *type = THREE_STAGED;
 387        }
 388
 389        /* Skip the entries with the same name */
 390        while (i < active_nr && ce_same_name(e, active_cache[i]))
 391                i++;
 392        return i;
 393}
 394
 395static int find_conflict(struct string_list *conflict)
 396{
 397        int i;
 398        if (read_cache() < 0)
 399                return error("Could not read index");
 400
 401        for (i = 0; i < active_nr;) {
 402                int conflict_type;
 403                const struct cache_entry *e = active_cache[i];
 404                i = check_one_conflict(i, &conflict_type);
 405                if (conflict_type == THREE_STAGED)
 406                        string_list_insert(conflict, (const char *)e->name);
 407        }
 408        return 0;
 409}
 410
 411int rerere_remaining(struct string_list *merge_rr)
 412{
 413        int i;
 414        if (read_cache() < 0)
 415                return error("Could not read index");
 416
 417        for (i = 0; i < active_nr;) {
 418                int conflict_type;
 419                const struct cache_entry *e = active_cache[i];
 420                i = check_one_conflict(i, &conflict_type);
 421                if (conflict_type == PUNTED)
 422                        string_list_insert(merge_rr, (const char *)e->name);
 423                else if (conflict_type == RESOLVED) {
 424                        struct string_list_item *it;
 425                        it = string_list_lookup(merge_rr, (const char *)e->name);
 426                        if (it != NULL) {
 427                                free(it->util);
 428                                it->util = RERERE_RESOLVED;
 429                        }
 430                }
 431        }
 432        return 0;
 433}
 434
 435static int merge(const char *name, const char *path)
 436{
 437        int ret;
 438        mmfile_t cur = {NULL, 0}, base = {NULL, 0}, other = {NULL, 0};
 439        mmbuffer_t result = {NULL, 0};
 440
 441        if (handle_file(path, NULL, rerere_path(name, "thisimage")) < 0)
 442                return 1;
 443
 444        if (read_mmfile(&cur, rerere_path(name, "thisimage")) ||
 445                        read_mmfile(&base, rerere_path(name, "preimage")) ||
 446                        read_mmfile(&other, rerere_path(name, "postimage"))) {
 447                ret = 1;
 448                goto out;
 449        }
 450        ret = ll_merge(&result, path, &base, NULL, &cur, "", &other, "", NULL);
 451        if (!ret) {
 452                FILE *f;
 453
 454                if (utime(rerere_path(name, "postimage"), NULL) < 0)
 455                        warning("failed utime() on %s: %s",
 456                                        rerere_path(name, "postimage"),
 457                                        strerror(errno));
 458                f = fopen(path, "w");
 459                if (!f)
 460                        return error("Could not open %s: %s", path,
 461                                     strerror(errno));
 462                if (fwrite(result.ptr, result.size, 1, f) != 1)
 463                        error("Could not write %s: %s", path, strerror(errno));
 464                if (fclose(f))
 465                        return error("Writing %s failed: %s", path,
 466                                     strerror(errno));
 467        }
 468
 469out:
 470        free(cur.ptr);
 471        free(base.ptr);
 472        free(other.ptr);
 473        free(result.ptr);
 474
 475        return ret;
 476}
 477
 478static struct lock_file index_lock;
 479
 480static int update_paths(struct string_list *update)
 481{
 482        int i;
 483        int fd = hold_locked_index(&index_lock, 0);
 484        int status = 0;
 485
 486        if (fd < 0)
 487                return -1;
 488
 489        for (i = 0; i < update->nr; i++) {
 490                struct string_list_item *item = &update->items[i];
 491                if (add_file_to_cache(item->string, ADD_CACHE_IGNORE_ERRORS))
 492                        status = -1;
 493        }
 494
 495        if (!status && active_cache_changed) {
 496                if (write_locked_index(&the_index, &index_lock, COMMIT_LOCK))
 497                        die("Unable to write new index file");
 498        } else if (fd >= 0)
 499                rollback_lock_file(&index_lock);
 500        return status;
 501}
 502
 503static int do_plain_rerere(struct string_list *rr, int fd)
 504{
 505        struct string_list conflict = STRING_LIST_INIT_DUP;
 506        struct string_list update = STRING_LIST_INIT_DUP;
 507        int i;
 508
 509        find_conflict(&conflict);
 510
 511        /*
 512         * MERGE_RR records paths with conflicts immediately after merge
 513         * failed.  Some of the conflicted paths might have been hand resolved
 514         * in the working tree since then, but the initial run would catch all
 515         * and register their preimages.
 516         */
 517
 518        for (i = 0; i < conflict.nr; i++) {
 519                const char *path = conflict.items[i].string;
 520                if (!string_list_has_string(rr, path)) {
 521                        unsigned char sha1[20];
 522                        char *hex;
 523                        int ret;
 524                        ret = handle_file(path, sha1, NULL);
 525                        if (ret < 1)
 526                                continue;
 527                        hex = xstrdup(sha1_to_hex(sha1));
 528                        string_list_insert(rr, path)->util = hex;
 529                        if (mkdir_in_gitdir(git_path("rr-cache/%s", hex)))
 530                                continue;
 531                        handle_file(path, NULL, rerere_path(hex, "preimage"));
 532                        fprintf(stderr, "Recorded preimage for '%s'\n", path);
 533                }
 534        }
 535
 536        /*
 537         * Now some of the paths that had conflicts earlier might have been
 538         * hand resolved.  Others may be similar to a conflict already that
 539         * was resolved before.
 540         */
 541
 542        for (i = 0; i < rr->nr; i++) {
 543                int ret;
 544                const char *path = rr->items[i].string;
 545                const char *name = (const char *)rr->items[i].util;
 546
 547                if (has_rerere_resolution(name)) {
 548                        if (!merge(name, path)) {
 549                                const char *msg;
 550                                if (rerere_autoupdate) {
 551                                        string_list_insert(&update, path);
 552                                        msg = "Staged '%s' using previous resolution.\n";
 553                                } else
 554                                        msg = "Resolved '%s' using previous resolution.\n";
 555                                fprintf(stderr, msg, path);
 556                                goto mark_resolved;
 557                        }
 558                }
 559
 560                /* Let's see if we have resolved it. */
 561                ret = handle_file(path, NULL, NULL);
 562                if (ret)
 563                        continue;
 564
 565                fprintf(stderr, "Recorded resolution for '%s'.\n", path);
 566                copy_file(rerere_path(name, "postimage"), path, 0666);
 567        mark_resolved:
 568                rr->items[i].util = NULL;
 569        }
 570
 571        if (update.nr)
 572                update_paths(&update);
 573
 574        return write_rr(rr, fd);
 575}
 576
 577static void git_rerere_config(void)
 578{
 579        git_config_get_bool("rerere.enabled", &rerere_enabled);
 580        git_config_get_bool("rerere.autoupdate", &rerere_autoupdate);
 581        git_config(git_default_config, NULL);
 582}
 583
 584static int is_rerere_enabled(void)
 585{
 586        const char *rr_cache;
 587        int rr_cache_exists;
 588
 589        if (!rerere_enabled)
 590                return 0;
 591
 592        rr_cache = git_path("rr-cache");
 593        rr_cache_exists = is_directory(rr_cache);
 594        if (rerere_enabled < 0)
 595                return rr_cache_exists;
 596
 597        if (!rr_cache_exists && mkdir_in_gitdir(rr_cache))
 598                die("Could not create directory %s", rr_cache);
 599        return 1;
 600}
 601
 602int setup_rerere(struct string_list *merge_rr, int flags)
 603{
 604        int fd;
 605
 606        git_rerere_config();
 607        if (!is_rerere_enabled())
 608                return -1;
 609
 610        if (flags & (RERERE_AUTOUPDATE|RERERE_NOAUTOUPDATE))
 611                rerere_autoupdate = !!(flags & RERERE_AUTOUPDATE);
 612        merge_rr_path = git_pathdup("MERGE_RR");
 613        fd = hold_lock_file_for_update(&write_lock, merge_rr_path,
 614                                       LOCK_DIE_ON_ERROR);
 615        read_rr(merge_rr);
 616        return fd;
 617}
 618
 619int rerere(int flags)
 620{
 621        struct string_list merge_rr = STRING_LIST_INIT_DUP;
 622        int fd;
 623
 624        fd = setup_rerere(&merge_rr, flags);
 625        if (fd < 0)
 626                return 0;
 627        return do_plain_rerere(&merge_rr, fd);
 628}
 629
 630static int rerere_forget_one_path(const char *path, struct string_list *rr)
 631{
 632        const char *filename;
 633        char *hex;
 634        unsigned char sha1[20];
 635        int ret;
 636
 637        ret = handle_cache(path, sha1, NULL);
 638        if (ret < 1)
 639                return error("Could not parse conflict hunks in '%s'", path);
 640        hex = xstrdup(sha1_to_hex(sha1));
 641        filename = rerere_path(hex, "postimage");
 642        if (unlink(filename))
 643                return (errno == ENOENT
 644                        ? error("no remembered resolution for %s", path)
 645                        : error("cannot unlink %s: %s", filename, strerror(errno)));
 646
 647        handle_cache(path, sha1, rerere_path(hex, "preimage"));
 648        fprintf(stderr, "Updated preimage for '%s'\n", path);
 649
 650
 651        string_list_insert(rr, path)->util = hex;
 652        fprintf(stderr, "Forgot resolution for %s\n", path);
 653        return 0;
 654}
 655
 656int rerere_forget(struct pathspec *pathspec)
 657{
 658        int i, fd;
 659        struct string_list conflict = STRING_LIST_INIT_DUP;
 660        struct string_list merge_rr = STRING_LIST_INIT_DUP;
 661
 662        if (read_cache() < 0)
 663                return error("Could not read index");
 664
 665        fd = setup_rerere(&merge_rr, RERERE_NOAUTOUPDATE);
 666
 667        unmerge_cache(pathspec);
 668        find_conflict(&conflict);
 669        for (i = 0; i < conflict.nr; i++) {
 670                struct string_list_item *it = &conflict.items[i];
 671                if (!match_pathspec(pathspec, it->string,
 672                                    strlen(it->string), 0, NULL, 0))
 673                        continue;
 674                rerere_forget_one_path(it->string, &merge_rr);
 675        }
 676        return write_rr(&merge_rr, fd);
 677}
 678
 679static time_t rerere_created_at(const char *name)
 680{
 681        struct stat st;
 682        return stat(rerere_path(name, "preimage"), &st) ? (time_t) 0 : st.st_mtime;
 683}
 684
 685static time_t rerere_last_used_at(const char *name)
 686{
 687        struct stat st;
 688        return stat(rerere_path(name, "postimage"), &st) ? (time_t) 0 : st.st_mtime;
 689}
 690
 691static void unlink_rr_item(const char *name)
 692{
 693        unlink(rerere_path(name, "thisimage"));
 694        unlink(rerere_path(name, "preimage"));
 695        unlink(rerere_path(name, "postimage"));
 696        rmdir(git_path("rr-cache/%s", name));
 697}
 698
 699void rerere_gc(struct string_list *rr)
 700{
 701        struct string_list to_remove = STRING_LIST_INIT_DUP;
 702        DIR *dir;
 703        struct dirent *e;
 704        int i, cutoff;
 705        time_t now = time(NULL), then;
 706        int cutoff_noresolve = 15;
 707        int cutoff_resolve = 60;
 708
 709        git_config_get_int("gc.rerereresolved", &cutoff_resolve);
 710        git_config_get_int("gc.rerereunresolved", &cutoff_noresolve);
 711        git_config(git_default_config, NULL);
 712        dir = opendir(git_path("rr-cache"));
 713        if (!dir)
 714                die_errno("unable to open rr-cache directory");
 715        while ((e = readdir(dir))) {
 716                if (is_dot_or_dotdot(e->d_name))
 717                        continue;
 718
 719                then = rerere_last_used_at(e->d_name);
 720                if (then) {
 721                        cutoff = cutoff_resolve;
 722                } else {
 723                        then = rerere_created_at(e->d_name);
 724                        if (!then)
 725                                continue;
 726                        cutoff = cutoff_noresolve;
 727                }
 728                if (then < now - cutoff * 86400)
 729                        string_list_append(&to_remove, e->d_name);
 730        }
 731        closedir(dir);
 732        for (i = 0; i < to_remove.nr; i++)
 733                unlink_rr_item(to_remove.items[i].string);
 734        string_list_clear(&to_remove, 0);
 735}
 736
 737void rerere_clear(struct string_list *merge_rr)
 738{
 739        int i;
 740
 741        for (i = 0; i < merge_rr->nr; i++) {
 742                const char *name = (const char *)merge_rr->items[i].util;
 743                if (!has_rerere_resolution(name))
 744                        unlink_rr_item(name);
 745        }
 746        unlink_or_warn(git_path("MERGE_RR"));
 747}