Andrew's git / gitweb.git / archive.c
?
archive.con commit tree-diff: avoid alloca for large allocations (b8ba412)
   1#include "cache.h"
   2#include "commit.h"
   3#include "tree-walk.h"
   4#include "attr.h"
   5#include "archive.h"
   6#include "parse-options.h"
   7#include "unpack-trees.h"
   8#include "dir.h"
   9
  10static char const * const archive_usage[] = {
  11        N_("git archive [<options>] <tree-ish> [<path>...]"),
  12        N_("git archive --list"),
  13        N_("git archive --remote <repo> [--exec <cmd>] [<options>] <tree-ish> [<path>...]"),
  14        N_("git archive --remote <repo> [--exec <cmd>] --list"),
  15        NULL
  16};
  17
  18static const struct archiver **archivers;
  19static int nr_archivers;
  20static int alloc_archivers;
  21static int remote_allow_unreachable;
  22
  23void register_archiver(struct archiver *ar)
  24{
  25        ALLOC_GROW(archivers, nr_archivers + 1, alloc_archivers);
  26        archivers[nr_archivers++] = ar;
  27}
  28
  29static void format_subst(const struct commit *commit,
  30                         const char *src, size_t len,
  31                         struct strbuf *buf)
  32{
  33        char *to_free = NULL;
  34        struct strbuf fmt = STRBUF_INIT;
  35        struct pretty_print_context ctx = {0};
  36        ctx.date_mode = DATE_NORMAL;
  37        ctx.abbrev = DEFAULT_ABBREV;
  38
  39        if (src == buf->buf)
  40                to_free = strbuf_detach(buf, NULL);
  41        for (;;) {
  42                const char *b, *c;
  43
  44                b = memmem(src, len, "$Format:", 8);
  45                if (!b)
  46                        break;
  47                c = memchr(b + 8, '$', (src + len) - b - 8);
  48                if (!c)
  49                        break;
  50
  51                strbuf_reset(&fmt);
  52                strbuf_add(&fmt, b + 8, c - b - 8);
  53
  54                strbuf_add(buf, src, b - src);
  55                format_commit_message(commit, fmt.buf, buf, &ctx);
  56                len -= c + 1 - src;
  57                src  = c + 1;
  58        }
  59        strbuf_add(buf, src, len);
  60        strbuf_release(&fmt);
  61        free(to_free);
  62}
  63
  64void *sha1_file_to_archive(const struct archiver_args *args,
  65                           const char *path, const unsigned char *sha1,
  66                           unsigned int mode, enum object_type *type,
  67                           unsigned long *sizep)
  68{
  69        void *buffer;
  70        const struct commit *commit = args->convert ? args->commit : NULL;
  71
  72        path += args->baselen;
  73        buffer = read_sha1_file(sha1, type, sizep);
  74        if (buffer && S_ISREG(mode)) {
  75                struct strbuf buf = STRBUF_INIT;
  76                size_t size = 0;
  77
  78                strbuf_attach(&buf, buffer, *sizep, *sizep + 1);
  79                convert_to_working_tree(path, buf.buf, buf.len, &buf);
  80                if (commit)
  81                        format_subst(commit, buf.buf, buf.len, &buf);
  82                buffer = strbuf_detach(&buf, &size);
  83                *sizep = size;
  84        }
  85
  86        return buffer;
  87}
  88
  89static void setup_archive_check(struct git_attr_check *check)
  90{
  91        static struct git_attr *attr_export_ignore;
  92        static struct git_attr *attr_export_subst;
  93
  94        if (!attr_export_ignore) {
  95                attr_export_ignore = git_attr("export-ignore");
  96                attr_export_subst = git_attr("export-subst");
  97        }
  98        check[0].attr = attr_export_ignore;
  99        check[1].attr = attr_export_subst;
 100}
 101
 102struct directory {
 103        struct directory *up;
 104        unsigned char sha1[20];
 105        int baselen, len;
 106        unsigned mode;
 107        int stage;
 108        char path[FLEX_ARRAY];
 109};
 110
 111struct archiver_context {
 112        struct archiver_args *args;
 113        write_archive_entry_fn_t write_entry;
 114        struct directory *bottom;
 115};
 116
 117static int write_archive_entry(const unsigned char *sha1, const char *base,
 118                int baselen, const char *filename, unsigned mode, int stage,
 119                void *context)
 120{
 121        static struct strbuf path = STRBUF_INIT;
 122        struct archiver_context *c = context;
 123        struct archiver_args *args = c->args;
 124        write_archive_entry_fn_t write_entry = c->write_entry;
 125        struct git_attr_check check[2];
 126        const char *path_without_prefix;
 127        int err;
 128
 129        args->convert = 0;
 130        strbuf_reset(&path);
 131        strbuf_grow(&path, PATH_MAX);
 132        strbuf_add(&path, args->base, args->baselen);
 133        strbuf_add(&path, base, baselen);
 134        strbuf_addstr(&path, filename);
 135        if (S_ISDIR(mode) || S_ISGITLINK(mode))
 136                strbuf_addch(&path, '/');
 137        path_without_prefix = path.buf + args->baselen;
 138
 139        setup_archive_check(check);
 140        if (!git_check_attr(path_without_prefix, ARRAY_SIZE(check), check)) {
 141                if (ATTR_TRUE(check[0].value))
 142                        return 0;
 143                args->convert = ATTR_TRUE(check[1].value);
 144        }
 145
 146        if (S_ISDIR(mode) || S_ISGITLINK(mode)) {
 147                if (args->verbose)
 148                        fprintf(stderr, "%.*s\n", (int)path.len, path.buf);
 149                err = write_entry(args, sha1, path.buf, path.len, mode);
 150                if (err)
 151                        return err;
 152                return (S_ISDIR(mode) ? READ_TREE_RECURSIVE : 0);
 153        }
 154
 155        if (args->verbose)
 156                fprintf(stderr, "%.*s\n", (int)path.len, path.buf);
 157        return write_entry(args, sha1, path.buf, path.len, mode);
 158}
 159
 160static int write_archive_entry_buf(const unsigned char *sha1, struct strbuf *base,
 161                const char *filename, unsigned mode, int stage,
 162                void *context)
 163{
 164        return write_archive_entry(sha1, base->buf, base->len,
 165                                     filename, mode, stage, context);
 166}
 167
 168static void queue_directory(const unsigned char *sha1,
 169                struct strbuf *base, const char *filename,
 170                unsigned mode, int stage, struct archiver_context *c)
 171{
 172        struct directory *d;
 173        d = xmallocz(sizeof(*d) + base->len + 1 + strlen(filename));
 174        d->up      = c->bottom;
 175        d->baselen = base->len;
 176        d->mode    = mode;
 177        d->stage   = stage;
 178        c->bottom  = d;
 179        d->len = sprintf(d->path, "%.*s%s/", (int)base->len, base->buf, filename);
 180        hashcpy(d->sha1, sha1);
 181}
 182
 183static int write_directory(struct archiver_context *c)
 184{
 185        struct directory *d = c->bottom;
 186        int ret;
 187
 188        if (!d)
 189                return 0;
 190        c->bottom = d->up;
 191        d->path[d->len - 1] = '\0'; /* no trailing slash */
 192        ret =
 193                write_directory(c) ||
 194                write_archive_entry(d->sha1, d->path, d->baselen,
 195                                    d->path + d->baselen, d->mode,
 196                                    d->stage, c) != READ_TREE_RECURSIVE;
 197        free(d);
 198        return ret ? -1 : 0;
 199}
 200
 201static int queue_or_write_archive_entry(const unsigned char *sha1,
 202                struct strbuf *base, const char *filename,
 203                unsigned mode, int stage, void *context)
 204{
 205        struct archiver_context *c = context;
 206
 207        while (c->bottom &&
 208               !(base->len >= c->bottom->len &&
 209                 !strncmp(base->buf, c->bottom->path, c->bottom->len))) {
 210                struct directory *next = c->bottom->up;
 211                free(c->bottom);
 212                c->bottom = next;
 213        }
 214
 215        if (S_ISDIR(mode)) {
 216                queue_directory(sha1, base, filename,
 217                                mode, stage, c);
 218                return READ_TREE_RECURSIVE;
 219        }
 220
 221        if (write_directory(c))
 222                return -1;
 223        return write_archive_entry(sha1, base->buf, base->len, filename, mode,
 224                                   stage, context);
 225}
 226
 227int write_archive_entries(struct archiver_args *args,
 228                write_archive_entry_fn_t write_entry)
 229{
 230        struct archiver_context context;
 231        struct unpack_trees_options opts;
 232        struct tree_desc t;
 233        int err;
 234
 235        if (args->baselen > 0 && args->base[args->baselen - 1] == '/') {
 236                size_t len = args->baselen;
 237
 238                while (len > 1 && args->base[len - 2] == '/')
 239                        len--;
 240                if (args->verbose)
 241                        fprintf(stderr, "%.*s\n", (int)len, args->base);
 242                err = write_entry(args, args->tree->object.sha1, args->base,
 243                                  len, 040777);
 244                if (err)
 245                        return err;
 246        }
 247
 248        memset(&context, 0, sizeof(context));
 249        context.args = args;
 250        context.write_entry = write_entry;
 251
 252        /*
 253         * Setup index and instruct attr to read index only
 254         */
 255        if (!args->worktree_attributes) {
 256                memset(&opts, 0, sizeof(opts));
 257                opts.index_only = 1;
 258                opts.head_idx = -1;
 259                opts.src_index = &the_index;
 260                opts.dst_index = &the_index;
 261                opts.fn = oneway_merge;
 262                init_tree_desc(&t, args->tree->buffer, args->tree->size);
 263                if (unpack_trees(1, &t, &opts))
 264                        return -1;
 265                git_attr_set_direction(GIT_ATTR_INDEX, &the_index);
 266        }
 267
 268        err = read_tree_recursive(args->tree, "", 0, 0, &args->pathspec,
 269                                  args->pathspec.has_wildcard ?
 270                                  queue_or_write_archive_entry :
 271                                  write_archive_entry_buf,
 272                                  &context);
 273        if (err == READ_TREE_RECURSIVE)
 274                err = 0;
 275        while (context.bottom) {
 276                struct directory *next = context.bottom->up;
 277                free(context.bottom);
 278                context.bottom = next;
 279        }
 280        return err;
 281}
 282
 283static const struct archiver *lookup_archiver(const char *name)
 284{
 285        int i;
 286
 287        if (!name)
 288                return NULL;
 289
 290        for (i = 0; i < nr_archivers; i++) {
 291                if (!strcmp(name, archivers[i]->name))
 292                        return archivers[i];
 293        }
 294        return NULL;
 295}
 296
 297static int reject_entry(const unsigned char *sha1, struct strbuf *base,
 298                        const char *filename, unsigned mode,
 299                        int stage, void *context)
 300{
 301        int ret = -1;
 302        if (S_ISDIR(mode)) {
 303                struct strbuf sb = STRBUF_INIT;
 304                strbuf_addbuf(&sb, base);
 305                strbuf_addstr(&sb, filename);
 306                if (!match_pathspec(context, sb.buf, sb.len, 0, NULL, 1))
 307                        ret = READ_TREE_RECURSIVE;
 308                strbuf_release(&sb);
 309        }
 310        return ret;
 311}
 312
 313static int path_exists(struct tree *tree, const char *path)
 314{
 315        const char *paths[] = { path, NULL };
 316        struct pathspec pathspec;
 317        int ret;
 318
 319        parse_pathspec(&pathspec, 0, 0, "", paths);
 320        pathspec.recursive = 1;
 321        ret = read_tree_recursive(tree, "", 0, 0, &pathspec,
 322                                  reject_entry, &pathspec);
 323        free_pathspec(&pathspec);
 324        return ret != 0;
 325}
 326
 327static void parse_pathspec_arg(const char **pathspec,
 328                struct archiver_args *ar_args)
 329{
 330        /*
 331         * must be consistent with parse_pathspec in path_exists()
 332         * Also if pathspec patterns are dependent, we're in big
 333         * trouble as we test each one separately
 334         */
 335        parse_pathspec(&ar_args->pathspec, 0,
 336                       PATHSPEC_PREFER_FULL,
 337                       "", pathspec);
 338        ar_args->pathspec.recursive = 1;
 339        if (pathspec) {
 340                while (*pathspec) {
 341                        if (**pathspec && !path_exists(ar_args->tree, *pathspec))
 342                                die(_("pathspec '%s' did not match any files"), *pathspec);
 343                        pathspec++;
 344                }
 345        }
 346}
 347
 348static void parse_treeish_arg(const char **argv,
 349                struct archiver_args *ar_args, const char *prefix,
 350                int remote)
 351{
 352        const char *name = argv[0];
 353        const unsigned char *commit_sha1;
 354        time_t archive_time;
 355        struct tree *tree;
 356        const struct commit *commit;
 357        unsigned char sha1[20];
 358
 359        /* Remotes are only allowed to fetch actual refs */
 360        if (remote && !remote_allow_unreachable) {
 361                char *ref = NULL;
 362                const char *colon = strchrnul(name, ':');
 363                int refnamelen = colon - name;
 364
 365                if (!dwim_ref(name, refnamelen, sha1, &ref))
 366                        die("no such ref: %.*s", refnamelen, name);
 367                free(ref);
 368        }
 369
 370        if (get_sha1(name, sha1))
 371                die("Not a valid object name");
 372
 373        commit = lookup_commit_reference_gently(sha1, 1);
 374        if (commit) {
 375                commit_sha1 = commit->object.sha1;
 376                archive_time = commit->date;
 377        } else {
 378                commit_sha1 = NULL;
 379                archive_time = time(NULL);
 380        }
 381
 382        tree = parse_tree_indirect(sha1);
 383        if (tree == NULL)
 384                die("not a tree object");
 385
 386        if (prefix) {
 387                unsigned char tree_sha1[20];
 388                unsigned int mode;
 389                int err;
 390
 391                err = get_tree_entry(tree->object.sha1, prefix,
 392                                     tree_sha1, &mode);
 393                if (err || !S_ISDIR(mode))
 394                        die("current working directory is untracked");
 395
 396                tree = parse_tree_indirect(tree_sha1);
 397        }
 398        ar_args->tree = tree;
 399        ar_args->commit_sha1 = commit_sha1;
 400        ar_args->commit = commit;
 401        ar_args->time = archive_time;
 402}
 403
 404#define OPT__COMPR(s, v, h, p) \
 405        { OPTION_SET_INT, (s), NULL, (v), NULL, (h), \
 406          PARSE_OPT_NOARG | PARSE_OPT_NONEG, NULL, (p) }
 407#define OPT__COMPR_HIDDEN(s, v, p) \
 408        { OPTION_SET_INT, (s), NULL, (v), NULL, "", \
 409          PARSE_OPT_NOARG | PARSE_OPT_NONEG | PARSE_OPT_HIDDEN, NULL, (p) }
 410
 411static int parse_archive_args(int argc, const char **argv,
 412                const struct archiver **ar, struct archiver_args *args,
 413                const char *name_hint, int is_remote)
 414{
 415        const char *format = NULL;
 416        const char *base = NULL;
 417        const char *remote = NULL;
 418        const char *exec = NULL;
 419        const char *output = NULL;
 420        int compression_level = -1;
 421        int verbose = 0;
 422        int i;
 423        int list = 0;
 424        int worktree_attributes = 0;
 425        struct option opts[] = {
 426                OPT_GROUP(""),
 427                OPT_STRING(0, "format", &format, N_("fmt"), N_("archive format")),
 428                OPT_STRING(0, "prefix", &base, N_("prefix"),
 429                        N_("prepend prefix to each pathname in the archive")),
 430                OPT_STRING('o', "output", &output, N_("file"),
 431                        N_("write the archive to this file")),
 432                OPT_BOOL(0, "worktree-attributes", &worktree_attributes,
 433                        N_("read .gitattributes in working directory")),
 434                OPT__VERBOSE(&verbose, N_("report archived files on stderr")),
 435                OPT__COMPR('0', &compression_level, N_("store only"), 0),
 436                OPT__COMPR('1', &compression_level, N_("compress faster"), 1),
 437                OPT__COMPR_HIDDEN('2', &compression_level, 2),
 438                OPT__COMPR_HIDDEN('3', &compression_level, 3),
 439                OPT__COMPR_HIDDEN('4', &compression_level, 4),
 440                OPT__COMPR_HIDDEN('5', &compression_level, 5),
 441                OPT__COMPR_HIDDEN('6', &compression_level, 6),
 442                OPT__COMPR_HIDDEN('7', &compression_level, 7),
 443                OPT__COMPR_HIDDEN('8', &compression_level, 8),
 444                OPT__COMPR('9', &compression_level, N_("compress better"), 9),
 445                OPT_GROUP(""),
 446                OPT_BOOL('l', "list", &list,
 447                        N_("list supported archive formats")),
 448                OPT_GROUP(""),
 449                OPT_STRING(0, "remote", &remote, N_("repo"),
 450                        N_("retrieve the archive from remote repository <repo>")),
 451                OPT_STRING(0, "exec", &exec, N_("command"),
 452                        N_("path to the remote git-upload-archive command")),
 453                OPT_END()
 454        };
 455
 456        argc = parse_options(argc, argv, NULL, opts, archive_usage, 0);
 457
 458        if (remote)
 459                die("Unexpected option --remote");
 460        if (exec)
 461                die("Option --exec can only be used together with --remote");
 462        if (output)
 463                die("Unexpected option --output");
 464
 465        if (!base)
 466                base = "";
 467
 468        if (list) {
 469                for (i = 0; i < nr_archivers; i++)
 470                        if (!is_remote || archivers[i]->flags & ARCHIVER_REMOTE)
 471                                printf("%s\n", archivers[i]->name);
 472                exit(0);
 473        }
 474
 475        if (!format && name_hint)
 476                format = archive_format_from_filename(name_hint);
 477        if (!format)
 478                format = "tar";
 479
 480        /* We need at least one parameter -- tree-ish */
 481        if (argc < 1)
 482                usage_with_options(archive_usage, opts);
 483        *ar = lookup_archiver(format);
 484        if (!*ar || (is_remote && !((*ar)->flags & ARCHIVER_REMOTE)))
 485                die("Unknown archive format '%s'", format);
 486
 487        args->compression_level = Z_DEFAULT_COMPRESSION;
 488        if (compression_level != -1) {
 489                if ((*ar)->flags & ARCHIVER_WANT_COMPRESSION_LEVELS)
 490                        args->compression_level = compression_level;
 491                else {
 492                        die("Argument not supported for format '%s': -%d",
 493                                        format, compression_level);
 494                }
 495        }
 496        args->verbose = verbose;
 497        args->base = base;
 498        args->baselen = strlen(base);
 499        args->worktree_attributes = worktree_attributes;
 500
 501        return argc;
 502}
 503
 504int write_archive(int argc, const char **argv, const char *prefix,
 505                  int setup_prefix, const char *name_hint, int remote)
 506{
 507        int nongit = 0;
 508        const struct archiver *ar = NULL;
 509        struct archiver_args args;
 510
 511        if (setup_prefix && prefix == NULL)
 512                prefix = setup_git_directory_gently(&nongit);
 513
 514        git_config_get_bool("uploadarchive.allowunreachable", &remote_allow_unreachable);
 515        git_config(git_default_config, NULL);
 516
 517        init_tar_archiver();
 518        init_zip_archiver();
 519
 520        argc = parse_archive_args(argc, argv, &ar, &args, name_hint, remote);
 521        if (nongit) {
 522                /*
 523                 * We know this will die() with an error, so we could just
 524                 * die ourselves; but its error message will be more specific
 525                 * than what we could write here.
 526                 */
 527                setup_git_directory();
 528        }
 529
 530        parse_treeish_arg(argv, &args, prefix, remote);
 531        parse_pathspec_arg(argv + 1, &args);
 532
 533        return ar->write_archive(ar, &args);
 534}
 535
 536static int match_extension(const char *filename, const char *ext)
 537{
 538        int prefixlen = strlen(filename) - strlen(ext);
 539
 540        /*
 541         * We need 1 character for the '.', and 1 character to ensure that the
 542         * prefix is non-empty (k.e., we don't match .tar.gz with no actual
 543         * filename).
 544         */
 545        if (prefixlen < 2 || filename[prefixlen - 1] != '.')
 546                return 0;
 547        return !strcmp(filename + prefixlen, ext);
 548}
 549
 550const char *archive_format_from_filename(const char *filename)
 551{
 552        int i;
 553
 554        for (i = 0; i < nr_archivers; i++)
 555                if (match_extension(filename, archivers[i]->name))
 556                        return archivers[i]->name;
 557        return NULL;
 558}