archive.con commit stash: Don't overwrite files that have gone from the index (7aa5d43)
   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
   9static char const * const archive_usage[] = {
  10        "git archive [options] <tree-ish> [path...]",
  11        "git archive --list",
  12        "git archive --remote <repo> [--exec <cmd>] [options] <tree-ish> [path...]",
  13        "git archive --remote <repo> [--exec <cmd>] --list",
  14        NULL
  15};
  16
  17#define USES_ZLIB_COMPRESSION 1
  18
  19static const struct archiver {
  20        const char *name;
  21        write_archive_fn_t write_archive;
  22        unsigned int flags;
  23} archivers[] = {
  24        { "tar", write_tar_archive },
  25        { "zip", write_zip_archive, USES_ZLIB_COMPRESSION },
  26};
  27
  28static void format_subst(const struct commit *commit,
  29                         const char *src, size_t len,
  30                         struct strbuf *buf)
  31{
  32        char *to_free = NULL;
  33        struct strbuf fmt = STRBUF_INIT;
  34        struct pretty_print_context ctx = {0};
  35        ctx.date_mode = DATE_NORMAL;
  36
  37        if (src == buf->buf)
  38                to_free = strbuf_detach(buf, NULL);
  39        for (;;) {
  40                const char *b, *c;
  41
  42                b = memmem(src, len, "$Format:", 8);
  43                if (!b)
  44                        break;
  45                c = memchr(b + 8, '$', (src + len) - b - 8);
  46                if (!c)
  47                        break;
  48
  49                strbuf_reset(&fmt);
  50                strbuf_add(&fmt, b + 8, c - b - 8);
  51
  52                strbuf_add(buf, src, b - src);
  53                format_commit_message(commit, fmt.buf, buf, &ctx);
  54                len -= c + 1 - src;
  55                src  = c + 1;
  56        }
  57        strbuf_add(buf, src, len);
  58        strbuf_release(&fmt);
  59        free(to_free);
  60}
  61
  62static void *sha1_file_to_archive(const char *path, const unsigned char *sha1,
  63                unsigned int mode, enum object_type *type,
  64                unsigned long *sizep, const struct commit *commit)
  65{
  66        void *buffer;
  67
  68        buffer = read_sha1_file(sha1, type, sizep);
  69        if (buffer && S_ISREG(mode)) {
  70                struct strbuf buf = STRBUF_INIT;
  71                size_t size = 0;
  72
  73                strbuf_attach(&buf, buffer, *sizep, *sizep + 1);
  74                convert_to_working_tree(path, buf.buf, buf.len, &buf);
  75                if (commit)
  76                        format_subst(commit, buf.buf, buf.len, &buf);
  77                buffer = strbuf_detach(&buf, &size);
  78                *sizep = size;
  79        }
  80
  81        return buffer;
  82}
  83
  84static void setup_archive_check(struct git_attr_check *check)
  85{
  86        static struct git_attr *attr_export_ignore;
  87        static struct git_attr *attr_export_subst;
  88
  89        if (!attr_export_ignore) {
  90                attr_export_ignore = git_attr("export-ignore");
  91                attr_export_subst = git_attr("export-subst");
  92        }
  93        check[0].attr = attr_export_ignore;
  94        check[1].attr = attr_export_subst;
  95}
  96
  97struct archiver_context {
  98        struct archiver_args *args;
  99        write_archive_entry_fn_t write_entry;
 100};
 101
 102static int write_archive_entry(const unsigned char *sha1, const char *base,
 103                int baselen, const char *filename, unsigned mode, int stage,
 104                void *context)
 105{
 106        static struct strbuf path = STRBUF_INIT;
 107        struct archiver_context *c = context;
 108        struct archiver_args *args = c->args;
 109        write_archive_entry_fn_t write_entry = c->write_entry;
 110        struct git_attr_check check[2];
 111        const char *path_without_prefix;
 112        int convert = 0;
 113        int err;
 114        enum object_type type;
 115        unsigned long size;
 116        void *buffer;
 117
 118        strbuf_reset(&path);
 119        strbuf_grow(&path, PATH_MAX);
 120        strbuf_add(&path, args->base, args->baselen);
 121        strbuf_add(&path, base, baselen);
 122        strbuf_addstr(&path, filename);
 123        path_without_prefix = path.buf + args->baselen;
 124
 125        setup_archive_check(check);
 126        if (!git_checkattr(path_without_prefix, ARRAY_SIZE(check), check)) {
 127                if (ATTR_TRUE(check[0].value))
 128                        return 0;
 129                convert = ATTR_TRUE(check[1].value);
 130        }
 131
 132        if (S_ISDIR(mode) || S_ISGITLINK(mode)) {
 133                strbuf_addch(&path, '/');
 134                if (args->verbose)
 135                        fprintf(stderr, "%.*s\n", (int)path.len, path.buf);
 136                err = write_entry(args, sha1, path.buf, path.len, mode, NULL, 0);
 137                if (err)
 138                        return err;
 139                return (S_ISDIR(mode) ? READ_TREE_RECURSIVE : 0);
 140        }
 141
 142        buffer = sha1_file_to_archive(path_without_prefix, sha1, mode,
 143                        &type, &size, convert ? args->commit : NULL);
 144        if (!buffer)
 145                return error("cannot read %s", sha1_to_hex(sha1));
 146        if (args->verbose)
 147                fprintf(stderr, "%.*s\n", (int)path.len, path.buf);
 148        err = write_entry(args, sha1, path.buf, path.len, mode, buffer, size);
 149        free(buffer);
 150        return err;
 151}
 152
 153int write_archive_entries(struct archiver_args *args,
 154                write_archive_entry_fn_t write_entry)
 155{
 156        struct archiver_context context;
 157        struct unpack_trees_options opts;
 158        struct tree_desc t;
 159        int err;
 160
 161        if (args->baselen > 0 && args->base[args->baselen - 1] == '/') {
 162                size_t len = args->baselen;
 163
 164                while (len > 1 && args->base[len - 2] == '/')
 165                        len--;
 166                if (args->verbose)
 167                        fprintf(stderr, "%.*s\n", (int)len, args->base);
 168                err = write_entry(args, args->tree->object.sha1, args->base,
 169                                len, 040777, NULL, 0);
 170                if (err)
 171                        return err;
 172        }
 173
 174        context.args = args;
 175        context.write_entry = write_entry;
 176
 177        /*
 178         * Setup index and instruct attr to read index only
 179         */
 180        if (!args->worktree_attributes) {
 181                memset(&opts, 0, sizeof(opts));
 182                opts.index_only = 1;
 183                opts.head_idx = -1;
 184                opts.src_index = &the_index;
 185                opts.dst_index = &the_index;
 186                opts.fn = oneway_merge;
 187                init_tree_desc(&t, args->tree->buffer, args->tree->size);
 188                if (unpack_trees(1, &t, &opts))
 189                        return -1;
 190                git_attr_set_direction(GIT_ATTR_INDEX, &the_index);
 191        }
 192
 193        err = read_tree_recursive(args->tree, "", 0, 0, args->pathspec,
 194                                  write_archive_entry, &context);
 195        if (err == READ_TREE_RECURSIVE)
 196                err = 0;
 197        return err;
 198}
 199
 200static const struct archiver *lookup_archiver(const char *name)
 201{
 202        int i;
 203
 204        if (!name)
 205                return NULL;
 206
 207        for (i = 0; i < ARRAY_SIZE(archivers); i++) {
 208                if (!strcmp(name, archivers[i].name))
 209                        return &archivers[i];
 210        }
 211        return NULL;
 212}
 213
 214static int reject_entry(const unsigned char *sha1, const char *base,
 215                        int baselen, const char *filename, unsigned mode,
 216                        int stage, void *context)
 217{
 218        return -1;
 219}
 220
 221static int path_exists(struct tree *tree, const char *path)
 222{
 223        const char *pathspec[] = { path, NULL };
 224
 225        if (read_tree_recursive(tree, "", 0, 0, pathspec, reject_entry, NULL))
 226                return 1;
 227        return 0;
 228}
 229
 230static void parse_pathspec_arg(const char **pathspec,
 231                struct archiver_args *ar_args)
 232{
 233        ar_args->pathspec = pathspec = get_pathspec("", pathspec);
 234        if (pathspec) {
 235                while (*pathspec) {
 236                        if (!path_exists(ar_args->tree, *pathspec))
 237                                die("path not found: %s", *pathspec);
 238                        pathspec++;
 239                }
 240        }
 241}
 242
 243static void parse_treeish_arg(const char **argv,
 244                struct archiver_args *ar_args, const char *prefix)
 245{
 246        const char *name = argv[0];
 247        const unsigned char *commit_sha1;
 248        time_t archive_time;
 249        struct tree *tree;
 250        const struct commit *commit;
 251        unsigned char sha1[20];
 252
 253        if (get_sha1(name, sha1))
 254                die("Not a valid object name");
 255
 256        commit = lookup_commit_reference_gently(sha1, 1);
 257        if (commit) {
 258                commit_sha1 = commit->object.sha1;
 259                archive_time = commit->date;
 260        } else {
 261                commit_sha1 = NULL;
 262                archive_time = time(NULL);
 263        }
 264
 265        tree = parse_tree_indirect(sha1);
 266        if (tree == NULL)
 267                die("not a tree object");
 268
 269        if (prefix) {
 270                unsigned char tree_sha1[20];
 271                unsigned int mode;
 272                int err;
 273
 274                err = get_tree_entry(tree->object.sha1, prefix,
 275                                     tree_sha1, &mode);
 276                if (err || !S_ISDIR(mode))
 277                        die("current working directory is untracked");
 278
 279                tree = parse_tree_indirect(tree_sha1);
 280        }
 281        ar_args->tree = tree;
 282        ar_args->commit_sha1 = commit_sha1;
 283        ar_args->commit = commit;
 284        ar_args->time = archive_time;
 285}
 286
 287#define OPT__COMPR(s, v, h, p) \
 288        { OPTION_SET_INT, (s), NULL, (v), NULL, (h), \
 289          PARSE_OPT_NOARG | PARSE_OPT_NONEG, NULL, (p) }
 290#define OPT__COMPR_HIDDEN(s, v, p) \
 291        { OPTION_SET_INT, (s), NULL, (v), NULL, "", \
 292          PARSE_OPT_NOARG | PARSE_OPT_NONEG | PARSE_OPT_HIDDEN, NULL, (p) }
 293
 294static int parse_archive_args(int argc, const char **argv,
 295                const struct archiver **ar, struct archiver_args *args)
 296{
 297        const char *format = "tar";
 298        const char *base = NULL;
 299        const char *remote = NULL;
 300        const char *exec = NULL;
 301        const char *output = NULL;
 302        int compression_level = -1;
 303        int verbose = 0;
 304        int i;
 305        int list = 0;
 306        int worktree_attributes = 0;
 307        struct option opts[] = {
 308                OPT_GROUP(""),
 309                OPT_STRING(0, "format", &format, "fmt", "archive format"),
 310                OPT_STRING(0, "prefix", &base, "prefix",
 311                        "prepend prefix to each pathname in the archive"),
 312                OPT_STRING('o', "output", &output, "file",
 313                        "write the archive to this file"),
 314                OPT_BOOLEAN(0, "worktree-attributes", &worktree_attributes,
 315                        "read .gitattributes in working directory"),
 316                OPT__VERBOSE(&verbose),
 317                OPT__COMPR('0', &compression_level, "store only", 0),
 318                OPT__COMPR('1', &compression_level, "compress faster", 1),
 319                OPT__COMPR_HIDDEN('2', &compression_level, 2),
 320                OPT__COMPR_HIDDEN('3', &compression_level, 3),
 321                OPT__COMPR_HIDDEN('4', &compression_level, 4),
 322                OPT__COMPR_HIDDEN('5', &compression_level, 5),
 323                OPT__COMPR_HIDDEN('6', &compression_level, 6),
 324                OPT__COMPR_HIDDEN('7', &compression_level, 7),
 325                OPT__COMPR_HIDDEN('8', &compression_level, 8),
 326                OPT__COMPR('9', &compression_level, "compress better", 9),
 327                OPT_GROUP(""),
 328                OPT_BOOLEAN('l', "list", &list,
 329                        "list supported archive formats"),
 330                OPT_GROUP(""),
 331                OPT_STRING(0, "remote", &remote, "repo",
 332                        "retrieve the archive from remote repository <repo>"),
 333                OPT_STRING(0, "exec", &exec, "cmd",
 334                        "path to the remote git-upload-archive command"),
 335                OPT_END()
 336        };
 337
 338        argc = parse_options(argc, argv, NULL, opts, archive_usage, 0);
 339
 340        if (remote)
 341                die("Unexpected option --remote");
 342        if (exec)
 343                die("Option --exec can only be used together with --remote");
 344        if (output)
 345                die("Unexpected option --output");
 346
 347        if (!base)
 348                base = "";
 349
 350        if (list) {
 351                for (i = 0; i < ARRAY_SIZE(archivers); i++)
 352                        printf("%s\n", archivers[i].name);
 353                exit(0);
 354        }
 355
 356        /* We need at least one parameter -- tree-ish */
 357        if (argc < 1)
 358                usage_with_options(archive_usage, opts);
 359        *ar = lookup_archiver(format);
 360        if (!*ar)
 361                die("Unknown archive format '%s'", format);
 362
 363        args->compression_level = Z_DEFAULT_COMPRESSION;
 364        if (compression_level != -1) {
 365                if ((*ar)->flags & USES_ZLIB_COMPRESSION)
 366                        args->compression_level = compression_level;
 367                else {
 368                        die("Argument not supported for format '%s': -%d",
 369                                        format, compression_level);
 370                }
 371        }
 372        args->verbose = verbose;
 373        args->base = base;
 374        args->baselen = strlen(base);
 375        args->worktree_attributes = worktree_attributes;
 376
 377        return argc;
 378}
 379
 380int write_archive(int argc, const char **argv, const char *prefix,
 381                int setup_prefix)
 382{
 383        const struct archiver *ar = NULL;
 384        struct archiver_args args;
 385
 386        argc = parse_archive_args(argc, argv, &ar, &args);
 387        if (setup_prefix && prefix == NULL)
 388                prefix = setup_git_directory();
 389
 390        parse_treeish_arg(argv, &args, prefix);
 391        parse_pathspec_arg(argv + 1, &args);
 392
 393        git_config(git_default_config, NULL);
 394
 395        return ar->write_archive(&args);
 396}