builtin / replace.con commit Merge branch 'jk/delta-islands-progress-fix' (a4c8352)
   1/*
   2 * Builtin "git replace"
   3 *
   4 * Copyright (c) 2008 Christian Couder <chriscool@tuxfamily.org>
   5 *
   6 * Based on builtin/tag.c by Kristian Høgsberg <krh@redhat.com>
   7 * and Carlos Rica <jasampler@gmail.com> that was itself based on
   8 * git-tag.sh and mktag.c by Linus Torvalds.
   9 */
  10
  11#include "cache.h"
  12#include "config.h"
  13#include "builtin.h"
  14#include "refs.h"
  15#include "parse-options.h"
  16#include "run-command.h"
  17#include "object-store.h"
  18#include "repository.h"
  19#include "tag.h"
  20
  21static const char * const git_replace_usage[] = {
  22        N_("git replace [-f] <object> <replacement>"),
  23        N_("git replace [-f] --edit <object>"),
  24        N_("git replace [-f] --graft <commit> [<parent>...]"),
  25        N_("git replace [-f] --convert-graft-file"),
  26        N_("git replace -d <object>..."),
  27        N_("git replace [--format=<format>] [-l [<pattern>]]"),
  28        NULL
  29};
  30
  31enum replace_format {
  32        REPLACE_FORMAT_SHORT,
  33        REPLACE_FORMAT_MEDIUM,
  34        REPLACE_FORMAT_LONG
  35};
  36
  37struct show_data {
  38        const char *pattern;
  39        enum replace_format format;
  40};
  41
  42static int show_reference(struct repository *r, const char *refname,
  43                          const struct object_id *oid,
  44                          int flag, void *cb_data)
  45{
  46        struct show_data *data = cb_data;
  47
  48        if (!wildmatch(data->pattern, refname, 0)) {
  49                if (data->format == REPLACE_FORMAT_SHORT)
  50                        printf("%s\n", refname);
  51                else if (data->format == REPLACE_FORMAT_MEDIUM)
  52                        printf("%s -> %s\n", refname, oid_to_hex(oid));
  53                else { /* data->format == REPLACE_FORMAT_LONG */
  54                        struct object_id object;
  55                        enum object_type obj_type, repl_type;
  56
  57                        if (get_oid(refname, &object))
  58                                return error(_("failed to resolve '%s' as a valid ref"), refname);
  59
  60                        obj_type = oid_object_info(r, &object, NULL);
  61                        repl_type = oid_object_info(r, oid, NULL);
  62
  63                        printf("%s (%s) -> %s (%s)\n", refname, type_name(obj_type),
  64                               oid_to_hex(oid), type_name(repl_type));
  65                }
  66        }
  67
  68        return 0;
  69}
  70
  71static int list_replace_refs(const char *pattern, const char *format)
  72{
  73        struct show_data data;
  74
  75        if (pattern == NULL)
  76                pattern = "*";
  77        data.pattern = pattern;
  78
  79        if (format == NULL || *format == '\0' || !strcmp(format, "short"))
  80                data.format = REPLACE_FORMAT_SHORT;
  81        else if (!strcmp(format, "medium"))
  82                data.format = REPLACE_FORMAT_MEDIUM;
  83        else if (!strcmp(format, "long"))
  84                data.format = REPLACE_FORMAT_LONG;
  85        /*
  86         * Please update _git_replace() in git-completion.bash when
  87         * you add new format
  88         */
  89        else
  90                return error(_("invalid replace format '%s'\n"
  91                               "valid formats are 'short', 'medium' and 'long'"),
  92                             format);
  93
  94        for_each_replace_ref(the_repository, show_reference, (void *)&data);
  95
  96        return 0;
  97}
  98
  99typedef int (*each_replace_name_fn)(const char *name, const char *ref,
 100                                    const struct object_id *oid);
 101
 102static int for_each_replace_name(const char **argv, each_replace_name_fn fn)
 103{
 104        const char **p, *full_hex;
 105        struct strbuf ref = STRBUF_INIT;
 106        size_t base_len;
 107        int had_error = 0;
 108        struct object_id oid;
 109
 110        strbuf_addstr(&ref, git_replace_ref_base);
 111        base_len = ref.len;
 112
 113        for (p = argv; *p; p++) {
 114                if (get_oid(*p, &oid)) {
 115                        error("failed to resolve '%s' as a valid ref", *p);
 116                        had_error = 1;
 117                        continue;
 118                }
 119
 120                strbuf_setlen(&ref, base_len);
 121                strbuf_addstr(&ref, oid_to_hex(&oid));
 122                full_hex = ref.buf + base_len;
 123
 124                if (read_ref(ref.buf, &oid)) {
 125                        error(_("replace ref '%s' not found"), full_hex);
 126                        had_error = 1;
 127                        continue;
 128                }
 129                if (fn(full_hex, ref.buf, &oid))
 130                        had_error = 1;
 131        }
 132        strbuf_release(&ref);
 133        return had_error;
 134}
 135
 136static int delete_replace_ref(const char *name, const char *ref,
 137                              const struct object_id *oid)
 138{
 139        if (delete_ref(NULL, ref, oid, 0))
 140                return 1;
 141        printf_ln(_("Deleted replace ref '%s'"), name);
 142        return 0;
 143}
 144
 145static int check_ref_valid(struct object_id *object,
 146                            struct object_id *prev,
 147                            struct strbuf *ref,
 148                            int force)
 149{
 150        strbuf_reset(ref);
 151        strbuf_addf(ref, "%s%s", git_replace_ref_base, oid_to_hex(object));
 152        if (check_refname_format(ref->buf, 0))
 153                return error(_("'%s' is not a valid ref name"), ref->buf);
 154
 155        if (read_ref(ref->buf, prev))
 156                oidclr(prev);
 157        else if (!force)
 158                return error(_("replace ref '%s' already exists"), ref->buf);
 159        return 0;
 160}
 161
 162static int replace_object_oid(const char *object_ref,
 163                               struct object_id *object,
 164                               const char *replace_ref,
 165                               struct object_id *repl,
 166                               int force)
 167{
 168        struct object_id prev;
 169        enum object_type obj_type, repl_type;
 170        struct strbuf ref = STRBUF_INIT;
 171        struct ref_transaction *transaction;
 172        struct strbuf err = STRBUF_INIT;
 173        int res = 0;
 174
 175        obj_type = oid_object_info(the_repository, object, NULL);
 176        repl_type = oid_object_info(the_repository, repl, NULL);
 177        if (!force && obj_type != repl_type)
 178                return error(_("Objects must be of the same type.\n"
 179                               "'%s' points to a replaced object of type '%s'\n"
 180                               "while '%s' points to a replacement object of "
 181                               "type '%s'."),
 182                             object_ref, type_name(obj_type),
 183                             replace_ref, type_name(repl_type));
 184
 185        if (check_ref_valid(object, &prev, &ref, force)) {
 186                strbuf_release(&ref);
 187                return -1;
 188        }
 189
 190        transaction = ref_transaction_begin(&err);
 191        if (!transaction ||
 192            ref_transaction_update(transaction, ref.buf, repl, &prev,
 193                                   0, NULL, &err) ||
 194            ref_transaction_commit(transaction, &err))
 195                res = error("%s", err.buf);
 196
 197        ref_transaction_free(transaction);
 198        strbuf_release(&ref);
 199        return res;
 200}
 201
 202static int replace_object(const char *object_ref, const char *replace_ref, int force)
 203{
 204        struct object_id object, repl;
 205
 206        if (get_oid(object_ref, &object))
 207                return error(_("failed to resolve '%s' as a valid ref"),
 208                             object_ref);
 209        if (get_oid(replace_ref, &repl))
 210                return error(_("failed to resolve '%s' as a valid ref"),
 211                             replace_ref);
 212
 213        return replace_object_oid(object_ref, &object, replace_ref, &repl, force);
 214}
 215
 216/*
 217 * Write the contents of the object named by "sha1" to the file "filename".
 218 * If "raw" is true, then the object's raw contents are printed according to
 219 * "type". Otherwise, we pretty-print the contents for human editing.
 220 */
 221static int export_object(const struct object_id *oid, enum object_type type,
 222                          int raw, const char *filename)
 223{
 224        struct child_process cmd = CHILD_PROCESS_INIT;
 225        int fd;
 226
 227        fd = open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0666);
 228        if (fd < 0)
 229                return error_errno(_("unable to open %s for writing"), filename);
 230
 231        argv_array_push(&cmd.args, "--no-replace-objects");
 232        argv_array_push(&cmd.args, "cat-file");
 233        if (raw)
 234                argv_array_push(&cmd.args, type_name(type));
 235        else
 236                argv_array_push(&cmd.args, "-p");
 237        argv_array_push(&cmd.args, oid_to_hex(oid));
 238        cmd.git_cmd = 1;
 239        cmd.out = fd;
 240
 241        if (run_command(&cmd))
 242                return error(_("cat-file reported failure"));
 243        return 0;
 244}
 245
 246/*
 247 * Read a previously-exported (and possibly edited) object back from "filename",
 248 * interpreting it as "type", and writing the result to the object database.
 249 * The sha1 of the written object is returned via sha1.
 250 */
 251static int import_object(struct object_id *oid, enum object_type type,
 252                          int raw, const char *filename)
 253{
 254        int fd;
 255
 256        fd = open(filename, O_RDONLY);
 257        if (fd < 0)
 258                return error_errno(_("unable to open %s for reading"), filename);
 259
 260        if (!raw && type == OBJ_TREE) {
 261                const char *argv[] = { "mktree", NULL };
 262                struct child_process cmd = CHILD_PROCESS_INIT;
 263                struct strbuf result = STRBUF_INIT;
 264
 265                cmd.argv = argv;
 266                cmd.git_cmd = 1;
 267                cmd.in = fd;
 268                cmd.out = -1;
 269
 270                if (start_command(&cmd)) {
 271                        close(fd);
 272                        return error(_("unable to spawn mktree"));
 273                }
 274
 275                if (strbuf_read(&result, cmd.out, 41) < 0) {
 276                        error_errno(_("unable to read from mktree"));
 277                        close(fd);
 278                        close(cmd.out);
 279                        return -1;
 280                }
 281                close(cmd.out);
 282
 283                if (finish_command(&cmd)) {
 284                        strbuf_release(&result);
 285                        return error(_("mktree reported failure"));
 286                }
 287                if (get_oid_hex(result.buf, oid) < 0) {
 288                        strbuf_release(&result);
 289                        return error(_("mktree did not return an object name"));
 290                }
 291
 292                strbuf_release(&result);
 293        } else {
 294                struct stat st;
 295                int flags = HASH_FORMAT_CHECK | HASH_WRITE_OBJECT;
 296
 297                if (fstat(fd, &st) < 0) {
 298                        error_errno(_("unable to fstat %s"), filename);
 299                        close(fd);
 300                        return -1;
 301                }
 302                if (index_fd(the_repository->index, oid, fd, &st, type, NULL, flags) < 0)
 303                        return error(_("unable to write object to database"));
 304                /* index_fd close()s fd for us */
 305        }
 306
 307        /*
 308         * No need to close(fd) here; both run-command and index-fd
 309         * will have done it for us.
 310         */
 311        return 0;
 312}
 313
 314static int edit_and_replace(const char *object_ref, int force, int raw)
 315{
 316        char *tmpfile;
 317        enum object_type type;
 318        struct object_id old_oid, new_oid, prev;
 319        struct strbuf ref = STRBUF_INIT;
 320
 321        if (get_oid(object_ref, &old_oid) < 0)
 322                return error(_("not a valid object name: '%s'"), object_ref);
 323
 324        type = oid_object_info(the_repository, &old_oid, NULL);
 325        if (type < 0)
 326                return error(_("unable to get object type for %s"),
 327                             oid_to_hex(&old_oid));
 328
 329        if (check_ref_valid(&old_oid, &prev, &ref, force)) {
 330                strbuf_release(&ref);
 331                return -1;
 332        }
 333        strbuf_release(&ref);
 334
 335        tmpfile = git_pathdup("REPLACE_EDITOBJ");
 336        if (export_object(&old_oid, type, raw, tmpfile)) {
 337                free(tmpfile);
 338                return -1;
 339        }
 340        if (launch_editor(tmpfile, NULL, NULL) < 0) {
 341                free(tmpfile);
 342                return error(_("editing object file failed"));
 343        }
 344        if (import_object(&new_oid, type, raw, tmpfile)) {
 345                free(tmpfile);
 346                return -1;
 347        }
 348        free(tmpfile);
 349
 350        if (oideq(&old_oid, &new_oid))
 351                return error(_("new object is the same as the old one: '%s'"), oid_to_hex(&old_oid));
 352
 353        return replace_object_oid(object_ref, &old_oid, "replacement", &new_oid, force);
 354}
 355
 356static int replace_parents(struct strbuf *buf, int argc, const char **argv)
 357{
 358        struct strbuf new_parents = STRBUF_INIT;
 359        const char *parent_start, *parent_end;
 360        int i;
 361
 362        /* find existing parents */
 363        parent_start = buf->buf;
 364        parent_start += GIT_SHA1_HEXSZ + 6; /* "tree " + "hex sha1" + "\n" */
 365        parent_end = parent_start;
 366
 367        while (starts_with(parent_end, "parent "))
 368                parent_end += 48; /* "parent " + "hex sha1" + "\n" */
 369
 370        /* prepare new parents */
 371        for (i = 0; i < argc; i++) {
 372                struct object_id oid;
 373                struct commit *commit;
 374
 375                if (get_oid(argv[i], &oid) < 0) {
 376                        strbuf_release(&new_parents);
 377                        return error(_("not a valid object name: '%s'"),
 378                                     argv[i]);
 379                }
 380                commit = lookup_commit_reference(the_repository, &oid);
 381                if (!commit) {
 382                        strbuf_release(&new_parents);
 383                        return error(_("could not parse %s as a commit"), argv[i]);
 384                }
 385                strbuf_addf(&new_parents, "parent %s\n", oid_to_hex(&commit->object.oid));
 386        }
 387
 388        /* replace existing parents with new ones */
 389        strbuf_splice(buf, parent_start - buf->buf, parent_end - parent_start,
 390                      new_parents.buf, new_parents.len);
 391
 392        strbuf_release(&new_parents);
 393        return 0;
 394}
 395
 396struct check_mergetag_data {
 397        int argc;
 398        const char **argv;
 399};
 400
 401static int check_one_mergetag(struct commit *commit,
 402                               struct commit_extra_header *extra,
 403                               void *data)
 404{
 405        struct check_mergetag_data *mergetag_data = (struct check_mergetag_data *)data;
 406        const char *ref = mergetag_data->argv[0];
 407        struct object_id tag_oid;
 408        struct tag *tag;
 409        int i;
 410
 411        hash_object_file(extra->value, extra->len, type_name(OBJ_TAG), &tag_oid);
 412        tag = lookup_tag(the_repository, &tag_oid);
 413        if (!tag)
 414                return error(_("bad mergetag in commit '%s'"), ref);
 415        if (parse_tag_buffer(the_repository, tag, extra->value, extra->len))
 416                return error(_("malformed mergetag in commit '%s'"), ref);
 417
 418        /* iterate over new parents */
 419        for (i = 1; i < mergetag_data->argc; i++) {
 420                struct object_id oid;
 421                if (get_oid(mergetag_data->argv[i], &oid) < 0)
 422                        return error(_("not a valid object name: '%s'"),
 423                                     mergetag_data->argv[i]);
 424                if (oideq(&tag->tagged->oid, &oid))
 425                        return 0; /* found */
 426        }
 427
 428        return error(_("original commit '%s' contains mergetag '%s' that is "
 429                       "discarded; use --edit instead of --graft"), ref,
 430                     oid_to_hex(&tag_oid));
 431}
 432
 433static int check_mergetags(struct commit *commit, int argc, const char **argv)
 434{
 435        struct check_mergetag_data mergetag_data;
 436
 437        mergetag_data.argc = argc;
 438        mergetag_data.argv = argv;
 439        return for_each_mergetag(check_one_mergetag, commit, &mergetag_data);
 440}
 441
 442static int create_graft(int argc, const char **argv, int force, int gentle)
 443{
 444        struct object_id old_oid, new_oid;
 445        const char *old_ref = argv[0];
 446        struct commit *commit;
 447        struct strbuf buf = STRBUF_INIT;
 448        const char *buffer;
 449        unsigned long size;
 450
 451        if (get_oid(old_ref, &old_oid) < 0)
 452                return error(_("not a valid object name: '%s'"), old_ref);
 453        commit = lookup_commit_reference(the_repository, &old_oid);
 454        if (!commit)
 455                return error(_("could not parse %s"), old_ref);
 456
 457        buffer = get_commit_buffer(commit, &size);
 458        strbuf_add(&buf, buffer, size);
 459        unuse_commit_buffer(commit, buffer);
 460
 461        if (replace_parents(&buf, argc - 1, &argv[1]) < 0) {
 462                strbuf_release(&buf);
 463                return -1;
 464        }
 465
 466        if (remove_signature(&buf)) {
 467                warning(_("the original commit '%s' has a gpg signature"), old_ref);
 468                warning(_("the signature will be removed in the replacement commit!"));
 469        }
 470
 471        if (check_mergetags(commit, argc, argv)) {
 472                strbuf_release(&buf);
 473                return -1;
 474        }
 475
 476        if (write_object_file(buf.buf, buf.len, commit_type, &new_oid)) {
 477                strbuf_release(&buf);
 478                return error(_("could not write replacement commit for: '%s'"),
 479                             old_ref);
 480        }
 481
 482        strbuf_release(&buf);
 483
 484        if (oideq(&commit->object.oid, &new_oid)) {
 485                if (gentle) {
 486                        warning(_("graft for '%s' unnecessary"),
 487                                oid_to_hex(&commit->object.oid));
 488                        return 0;
 489                }
 490                return error(_("new commit is the same as the old one: '%s'"),
 491                             oid_to_hex(&commit->object.oid));
 492        }
 493
 494        return replace_object_oid(old_ref, &commit->object.oid,
 495                                  "replacement", &new_oid, force);
 496}
 497
 498static int convert_graft_file(int force)
 499{
 500        const char *graft_file = get_graft_file(the_repository);
 501        FILE *fp = fopen_or_warn(graft_file, "r");
 502        struct strbuf buf = STRBUF_INIT, err = STRBUF_INIT;
 503        struct argv_array args = ARGV_ARRAY_INIT;
 504
 505        if (!fp)
 506                return -1;
 507
 508        advice_graft_file_deprecated = 0;
 509        while (strbuf_getline(&buf, fp) != EOF) {
 510                if (*buf.buf == '#')
 511                        continue;
 512
 513                argv_array_split(&args, buf.buf);
 514                if (args.argc && create_graft(args.argc, args.argv, force, 1))
 515                        strbuf_addf(&err, "\n\t%s", buf.buf);
 516                argv_array_clear(&args);
 517        }
 518        fclose(fp);
 519
 520        strbuf_release(&buf);
 521
 522        if (!err.len)
 523                return unlink_or_warn(graft_file);
 524
 525        warning(_("could not convert the following graft(s):\n%s"), err.buf);
 526        strbuf_release(&err);
 527
 528        return -1;
 529}
 530
 531int cmd_replace(int argc, const char **argv, const char *prefix)
 532{
 533        int force = 0;
 534        int raw = 0;
 535        const char *format = NULL;
 536        enum {
 537                MODE_UNSPECIFIED = 0,
 538                MODE_LIST,
 539                MODE_DELETE,
 540                MODE_EDIT,
 541                MODE_GRAFT,
 542                MODE_CONVERT_GRAFT_FILE,
 543                MODE_REPLACE
 544        } cmdmode = MODE_UNSPECIFIED;
 545        struct option options[] = {
 546                OPT_CMDMODE('l', "list", &cmdmode, N_("list replace refs"), MODE_LIST),
 547                OPT_CMDMODE('d', "delete", &cmdmode, N_("delete replace refs"), MODE_DELETE),
 548                OPT_CMDMODE('e', "edit", &cmdmode, N_("edit existing object"), MODE_EDIT),
 549                OPT_CMDMODE('g', "graft", &cmdmode, N_("change a commit's parents"), MODE_GRAFT),
 550                OPT_CMDMODE(0, "convert-graft-file", &cmdmode, N_("convert existing graft file"), MODE_CONVERT_GRAFT_FILE),
 551                OPT_BOOL_F('f', "force", &force, N_("replace the ref if it exists"),
 552                           PARSE_OPT_NOCOMPLETE),
 553                OPT_BOOL(0, "raw", &raw, N_("do not pretty-print contents for --edit")),
 554                OPT_STRING(0, "format", &format, N_("format"), N_("use this format")),
 555                OPT_END()
 556        };
 557
 558        read_replace_refs = 0;
 559        git_config(git_default_config, NULL);
 560
 561        argc = parse_options(argc, argv, prefix, options, git_replace_usage, 0);
 562
 563        if (!cmdmode)
 564                cmdmode = argc ? MODE_REPLACE : MODE_LIST;
 565
 566        if (format && cmdmode != MODE_LIST)
 567                usage_msg_opt(_("--format cannot be used when not listing"),
 568                              git_replace_usage, options);
 569
 570        if (force &&
 571            cmdmode != MODE_REPLACE &&
 572            cmdmode != MODE_EDIT &&
 573            cmdmode != MODE_GRAFT &&
 574            cmdmode != MODE_CONVERT_GRAFT_FILE)
 575                usage_msg_opt(_("-f only makes sense when writing a replacement"),
 576                              git_replace_usage, options);
 577
 578        if (raw && cmdmode != MODE_EDIT)
 579                usage_msg_opt(_("--raw only makes sense with --edit"),
 580                              git_replace_usage, options);
 581
 582        switch (cmdmode) {
 583        case MODE_DELETE:
 584                if (argc < 1)
 585                        usage_msg_opt(_("-d needs at least one argument"),
 586                                      git_replace_usage, options);
 587                return for_each_replace_name(argv, delete_replace_ref);
 588
 589        case MODE_REPLACE:
 590                if (argc != 2)
 591                        usage_msg_opt(_("bad number of arguments"),
 592                                      git_replace_usage, options);
 593                return replace_object(argv[0], argv[1], force);
 594
 595        case MODE_EDIT:
 596                if (argc != 1)
 597                        usage_msg_opt(_("-e needs exactly one argument"),
 598                                      git_replace_usage, options);
 599                return edit_and_replace(argv[0], force, raw);
 600
 601        case MODE_GRAFT:
 602                if (argc < 1)
 603                        usage_msg_opt(_("-g needs at least one argument"),
 604                                      git_replace_usage, options);
 605                return create_graft(argc, argv, force, 0);
 606
 607        case MODE_CONVERT_GRAFT_FILE:
 608                if (argc != 0)
 609                        usage_msg_opt(_("--convert-graft-file takes no argument"),
 610                                      git_replace_usage, options);
 611                return !!convert_graft_file(force);
 612
 613        case MODE_LIST:
 614                if (argc > 1)
 615                        usage_msg_opt(_("only one pattern can be given with -l"),
 616                                      git_replace_usage, options);
 617                return list_replace_refs(argv[0], format);
 618
 619        default:
 620                BUG("invalid cmdmode %d", (int)cmdmode);
 621        }
 622}