range-diff doc: add a section about output stability
[git] / archive.c
1 #include "cache.h"
2 #include "config.h"
3 #include "refs.h"
4 #include "object-store.h"
5 #include "commit.h"
6 #include "tree-walk.h"
7 #include "attr.h"
8 #include "archive.h"
9 #include "parse-options.h"
10 #include "unpack-trees.h"
11 #include "dir.h"
12
13 static char const * const archive_usage[] = {
14         N_("git archive [<options>] <tree-ish> [<path>...]"),
15         N_("git archive --list"),
16         N_("git archive --remote <repo> [--exec <cmd>] [<options>] <tree-ish> [<path>...]"),
17         N_("git archive --remote <repo> [--exec <cmd>] --list"),
18         NULL
19 };
20
21 static const struct archiver **archivers;
22 static int nr_archivers;
23 static int alloc_archivers;
24 static int remote_allow_unreachable;
25
26 void register_archiver(struct archiver *ar)
27 {
28         ALLOC_GROW(archivers, nr_archivers + 1, alloc_archivers);
29         archivers[nr_archivers++] = ar;
30 }
31
32 static void format_subst(const struct commit *commit,
33                          const char *src, size_t len,
34                          struct strbuf *buf)
35 {
36         char *to_free = NULL;
37         struct strbuf fmt = STRBUF_INIT;
38         struct pretty_print_context ctx = {0};
39         ctx.date_mode.type = DATE_NORMAL;
40         ctx.abbrev = DEFAULT_ABBREV;
41
42         if (src == buf->buf)
43                 to_free = strbuf_detach(buf, NULL);
44         for (;;) {
45                 const char *b, *c;
46
47                 b = memmem(src, len, "$Format:", 8);
48                 if (!b)
49                         break;
50                 c = memchr(b + 8, '$', (src + len) - b - 8);
51                 if (!c)
52                         break;
53
54                 strbuf_reset(&fmt);
55                 strbuf_add(&fmt, b + 8, c - b - 8);
56
57                 strbuf_add(buf, src, b - src);
58                 format_commit_message(commit, fmt.buf, buf, &ctx);
59                 len -= c + 1 - src;
60                 src  = c + 1;
61         }
62         strbuf_add(buf, src, len);
63         strbuf_release(&fmt);
64         free(to_free);
65 }
66
67 void *object_file_to_archive(const struct archiver_args *args,
68                              const char *path, const struct object_id *oid,
69                              unsigned int mode, enum object_type *type,
70                              unsigned long *sizep)
71 {
72         void *buffer;
73         const struct commit *commit = args->convert ? args->commit : NULL;
74
75         path += args->baselen;
76         buffer = read_object_file(oid, type, sizep);
77         if (buffer && S_ISREG(mode)) {
78                 struct strbuf buf = STRBUF_INIT;
79                 size_t size = 0;
80
81                 strbuf_attach(&buf, buffer, *sizep, *sizep + 1);
82                 convert_to_working_tree(path, buf.buf, buf.len, &buf);
83                 if (commit)
84                         format_subst(commit, buf.buf, buf.len, &buf);
85                 buffer = strbuf_detach(&buf, &size);
86                 *sizep = size;
87         }
88
89         return buffer;
90 }
91
92 struct directory {
93         struct directory *up;
94         struct object_id oid;
95         int baselen, len;
96         unsigned mode;
97         int stage;
98         char path[FLEX_ARRAY];
99 };
100
101 struct archiver_context {
102         struct archiver_args *args;
103         write_archive_entry_fn_t write_entry;
104         struct directory *bottom;
105 };
106
107 static const struct attr_check *get_archive_attrs(const char *path)
108 {
109         static struct attr_check *check;
110         if (!check)
111                 check = attr_check_initl("export-ignore", "export-subst", NULL);
112         return git_check_attr(path, check) ? NULL : check;
113 }
114
115 static int check_attr_export_ignore(const struct attr_check *check)
116 {
117         return check && ATTR_TRUE(check->items[0].value);
118 }
119
120 static int check_attr_export_subst(const struct attr_check *check)
121 {
122         return check && ATTR_TRUE(check->items[1].value);
123 }
124
125 static int write_archive_entry(const struct object_id *oid, const char *base,
126                 int baselen, const char *filename, unsigned mode, int stage,
127                 void *context)
128 {
129         static struct strbuf path = STRBUF_INIT;
130         struct archiver_context *c = context;
131         struct archiver_args *args = c->args;
132         write_archive_entry_fn_t write_entry = c->write_entry;
133         int err;
134         const char *path_without_prefix;
135
136         args->convert = 0;
137         strbuf_reset(&path);
138         strbuf_grow(&path, PATH_MAX);
139         strbuf_add(&path, args->base, args->baselen);
140         strbuf_add(&path, base, baselen);
141         strbuf_addstr(&path, filename);
142         if (S_ISDIR(mode) || S_ISGITLINK(mode))
143                 strbuf_addch(&path, '/');
144         path_without_prefix = path.buf + args->baselen;
145
146         if (!S_ISDIR(mode)) {
147                 const struct attr_check *check;
148                 check = get_archive_attrs(path_without_prefix);
149                 if (check_attr_export_ignore(check))
150                         return 0;
151                 args->convert = check_attr_export_subst(check);
152         }
153
154         if (S_ISDIR(mode) || S_ISGITLINK(mode)) {
155                 if (args->verbose)
156                         fprintf(stderr, "%.*s\n", (int)path.len, path.buf);
157                 err = write_entry(args, oid, path.buf, path.len, mode);
158                 if (err)
159                         return err;
160                 return (S_ISDIR(mode) ? READ_TREE_RECURSIVE : 0);
161         }
162
163         if (args->verbose)
164                 fprintf(stderr, "%.*s\n", (int)path.len, path.buf);
165         return write_entry(args, oid, path.buf, path.len, mode);
166 }
167
168 static 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         size_t len = st_add4(base->len, 1, strlen(filename), 1);
174         d = xmalloc(st_add(sizeof(*d), len));
175         d->up      = c->bottom;
176         d->baselen = base->len;
177         d->mode    = mode;
178         d->stage   = stage;
179         c->bottom  = d;
180         d->len = xsnprintf(d->path, len, "%.*s%s/", (int)base->len, base->buf, filename);
181         hashcpy(d->oid.hash, sha1);
182 }
183
184 static int write_directory(struct archiver_context *c)
185 {
186         struct directory *d = c->bottom;
187         int ret;
188
189         if (!d)
190                 return 0;
191         c->bottom = d->up;
192         d->path[d->len - 1] = '\0'; /* no trailing slash */
193         ret =
194                 write_directory(c) ||
195                 write_archive_entry(&d->oid, d->path, d->baselen,
196                                     d->path + d->baselen, d->mode,
197                                     d->stage, c) != READ_TREE_RECURSIVE;
198         free(d);
199         return ret ? -1 : 0;
200 }
201
202 static int queue_or_write_archive_entry(const struct object_id *oid,
203                 struct strbuf *base, const char *filename,
204                 unsigned mode, int stage, void *context)
205 {
206         struct archiver_context *c = context;
207
208         while (c->bottom &&
209                !(base->len >= c->bottom->len &&
210                  !strncmp(base->buf, c->bottom->path, c->bottom->len))) {
211                 struct directory *next = c->bottom->up;
212                 free(c->bottom);
213                 c->bottom = next;
214         }
215
216         if (S_ISDIR(mode)) {
217                 size_t baselen = base->len;
218                 const struct attr_check *check;
219
220                 /* Borrow base, but restore its original value when done. */
221                 strbuf_addstr(base, filename);
222                 strbuf_addch(base, '/');
223                 check = get_archive_attrs(base->buf);
224                 strbuf_setlen(base, baselen);
225
226                 if (check_attr_export_ignore(check))
227                         return 0;
228                 queue_directory(oid->hash, base, filename,
229                                 mode, stage, c);
230                 return READ_TREE_RECURSIVE;
231         }
232
233         if (write_directory(c))
234                 return -1;
235         return write_archive_entry(oid, base->buf, base->len, filename, mode,
236                                    stage, context);
237 }
238
239 int write_archive_entries(struct archiver_args *args,
240                 write_archive_entry_fn_t write_entry)
241 {
242         struct archiver_context context;
243         struct unpack_trees_options opts;
244         struct tree_desc t;
245         int err;
246
247         if (args->baselen > 0 && args->base[args->baselen - 1] == '/') {
248                 size_t len = args->baselen;
249
250                 while (len > 1 && args->base[len - 2] == '/')
251                         len--;
252                 if (args->verbose)
253                         fprintf(stderr, "%.*s\n", (int)len, args->base);
254                 err = write_entry(args, &args->tree->object.oid, args->base,
255                                   len, 040777);
256                 if (err)
257                         return err;
258         }
259
260         memset(&context, 0, sizeof(context));
261         context.args = args;
262         context.write_entry = write_entry;
263
264         /*
265          * Setup index and instruct attr to read index only
266          */
267         if (!args->worktree_attributes) {
268                 memset(&opts, 0, sizeof(opts));
269                 opts.index_only = 1;
270                 opts.head_idx = -1;
271                 opts.src_index = &the_index;
272                 opts.dst_index = &the_index;
273                 opts.fn = oneway_merge;
274                 init_tree_desc(&t, args->tree->buffer, args->tree->size);
275                 if (unpack_trees(1, &t, &opts))
276                         return -1;
277                 git_attr_set_direction(GIT_ATTR_INDEX, &the_index);
278         }
279
280         err = read_tree_recursive(args->tree, "", 0, 0, &args->pathspec,
281                                   queue_or_write_archive_entry,
282                                   &context);
283         if (err == READ_TREE_RECURSIVE)
284                 err = 0;
285         while (context.bottom) {
286                 struct directory *next = context.bottom->up;
287                 free(context.bottom);
288                 context.bottom = next;
289         }
290         return err;
291 }
292
293 static const struct archiver *lookup_archiver(const char *name)
294 {
295         int i;
296
297         if (!name)
298                 return NULL;
299
300         for (i = 0; i < nr_archivers; i++) {
301                 if (!strcmp(name, archivers[i]->name))
302                         return archivers[i];
303         }
304         return NULL;
305 }
306
307 static int reject_entry(const struct object_id *oid, struct strbuf *base,
308                         const char *filename, unsigned mode,
309                         int stage, void *context)
310 {
311         int ret = -1;
312         if (S_ISDIR(mode)) {
313                 struct strbuf sb = STRBUF_INIT;
314                 strbuf_addbuf(&sb, base);
315                 strbuf_addstr(&sb, filename);
316                 if (!match_pathspec(context, sb.buf, sb.len, 0, NULL, 1))
317                         ret = READ_TREE_RECURSIVE;
318                 strbuf_release(&sb);
319         }
320         return ret;
321 }
322
323 static int path_exists(struct tree *tree, const char *path)
324 {
325         const char *paths[] = { path, NULL };
326         struct pathspec pathspec;
327         int ret;
328
329         parse_pathspec(&pathspec, 0, 0, "", paths);
330         pathspec.recursive = 1;
331         ret = read_tree_recursive(tree, "", 0, 0, &pathspec,
332                                   reject_entry, &pathspec);
333         clear_pathspec(&pathspec);
334         return ret != 0;
335 }
336
337 static void parse_pathspec_arg(const char **pathspec,
338                 struct archiver_args *ar_args)
339 {
340         /*
341          * must be consistent with parse_pathspec in path_exists()
342          * Also if pathspec patterns are dependent, we're in big
343          * trouble as we test each one separately
344          */
345         parse_pathspec(&ar_args->pathspec, 0,
346                        PATHSPEC_PREFER_FULL,
347                        "", pathspec);
348         ar_args->pathspec.recursive = 1;
349         if (pathspec) {
350                 while (*pathspec) {
351                         if (**pathspec && !path_exists(ar_args->tree, *pathspec))
352                                 die(_("pathspec '%s' did not match any files"), *pathspec);
353                         pathspec++;
354                 }
355         }
356 }
357
358 static void parse_treeish_arg(const char **argv,
359                 struct archiver_args *ar_args, const char *prefix,
360                 int remote)
361 {
362         const char *name = argv[0];
363         const unsigned char *commit_sha1;
364         time_t archive_time;
365         struct tree *tree;
366         const struct commit *commit;
367         struct object_id oid;
368
369         /* Remotes are only allowed to fetch actual refs */
370         if (remote && !remote_allow_unreachable) {
371                 char *ref = NULL;
372                 const char *colon = strchrnul(name, ':');
373                 int refnamelen = colon - name;
374
375                 if (!dwim_ref(name, refnamelen, &oid, &ref))
376                         die("no such ref: %.*s", refnamelen, name);
377                 free(ref);
378         }
379
380         if (get_oid(name, &oid))
381                 die("Not a valid object name");
382
383         commit = lookup_commit_reference_gently(the_repository, &oid, 1);
384         if (commit) {
385                 commit_sha1 = commit->object.oid.hash;
386                 archive_time = commit->date;
387         } else {
388                 commit_sha1 = NULL;
389                 archive_time = time(NULL);
390         }
391
392         tree = parse_tree_indirect(&oid);
393         if (tree == NULL)
394                 die("not a tree object");
395
396         if (prefix) {
397                 struct object_id tree_oid;
398                 unsigned int mode;
399                 int err;
400
401                 err = get_tree_entry(&tree->object.oid, prefix, &tree_oid,
402                                      &mode);
403                 if (err || !S_ISDIR(mode))
404                         die("current working directory is untracked");
405
406                 tree = parse_tree_indirect(&tree_oid);
407         }
408         ar_args->tree = tree;
409         ar_args->commit_sha1 = commit_sha1;
410         ar_args->commit = commit;
411         ar_args->time = archive_time;
412 }
413
414 #define OPT__COMPR(s, v, h, p) \
415         OPT_SET_INT_F(s, NULL, v, h, p, PARSE_OPT_NONEG)
416 #define OPT__COMPR_HIDDEN(s, v, p) \
417         OPT_SET_INT_F(s, NULL, v, "", p, PARSE_OPT_NONEG | PARSE_OPT_HIDDEN)
418
419 static int parse_archive_args(int argc, const char **argv,
420                 const struct archiver **ar, struct archiver_args *args,
421                 const char *name_hint, int is_remote)
422 {
423         const char *format = NULL;
424         const char *base = NULL;
425         const char *remote = NULL;
426         const char *exec = NULL;
427         const char *output = NULL;
428         int compression_level = -1;
429         int verbose = 0;
430         int i;
431         int list = 0;
432         int worktree_attributes = 0;
433         struct option opts[] = {
434                 OPT_GROUP(""),
435                 OPT_STRING(0, "format", &format, N_("fmt"), N_("archive format")),
436                 OPT_STRING(0, "prefix", &base, N_("prefix"),
437                         N_("prepend prefix to each pathname in the archive")),
438                 OPT_STRING('o', "output", &output, N_("file"),
439                         N_("write the archive to this file")),
440                 OPT_BOOL(0, "worktree-attributes", &worktree_attributes,
441                         N_("read .gitattributes in working directory")),
442                 OPT__VERBOSE(&verbose, N_("report archived files on stderr")),
443                 OPT__COMPR('0', &compression_level, N_("store only"), 0),
444                 OPT__COMPR('1', &compression_level, N_("compress faster"), 1),
445                 OPT__COMPR_HIDDEN('2', &compression_level, 2),
446                 OPT__COMPR_HIDDEN('3', &compression_level, 3),
447                 OPT__COMPR_HIDDEN('4', &compression_level, 4),
448                 OPT__COMPR_HIDDEN('5', &compression_level, 5),
449                 OPT__COMPR_HIDDEN('6', &compression_level, 6),
450                 OPT__COMPR_HIDDEN('7', &compression_level, 7),
451                 OPT__COMPR_HIDDEN('8', &compression_level, 8),
452                 OPT__COMPR('9', &compression_level, N_("compress better"), 9),
453                 OPT_GROUP(""),
454                 OPT_BOOL('l', "list", &list,
455                         N_("list supported archive formats")),
456                 OPT_GROUP(""),
457                 OPT_STRING(0, "remote", &remote, N_("repo"),
458                         N_("retrieve the archive from remote repository <repo>")),
459                 OPT_STRING(0, "exec", &exec, N_("command"),
460                         N_("path to the remote git-upload-archive command")),
461                 OPT_END()
462         };
463
464         argc = parse_options(argc, argv, NULL, opts, archive_usage, 0);
465
466         if (remote)
467                 die(_("Unexpected option --remote"));
468         if (exec)
469                 die(_("Option --exec can only be used together with --remote"));
470         if (output)
471                 die(_("Unexpected option --output"));
472
473         if (!base)
474                 base = "";
475
476         if (list) {
477                 for (i = 0; i < nr_archivers; i++)
478                         if (!is_remote || archivers[i]->flags & ARCHIVER_REMOTE)
479                                 printf("%s\n", archivers[i]->name);
480                 exit(0);
481         }
482
483         if (!format && name_hint)
484                 format = archive_format_from_filename(name_hint);
485         if (!format)
486                 format = "tar";
487
488         /* We need at least one parameter -- tree-ish */
489         if (argc < 1)
490                 usage_with_options(archive_usage, opts);
491         *ar = lookup_archiver(format);
492         if (!*ar || (is_remote && !((*ar)->flags & ARCHIVER_REMOTE)))
493                 die(_("Unknown archive format '%s'"), format);
494
495         args->compression_level = Z_DEFAULT_COMPRESSION;
496         if (compression_level != -1) {
497                 if ((*ar)->flags & ARCHIVER_WANT_COMPRESSION_LEVELS)
498                         args->compression_level = compression_level;
499                 else {
500                         die(_("Argument not supported for format '%s': -%d"),
501                                         format, compression_level);
502                 }
503         }
504         args->verbose = verbose;
505         args->base = base;
506         args->baselen = strlen(base);
507         args->worktree_attributes = worktree_attributes;
508
509         return argc;
510 }
511
512 int write_archive(int argc, const char **argv, const char *prefix,
513                   const char *name_hint, int remote)
514 {
515         const struct archiver *ar = NULL;
516         struct archiver_args args;
517
518         git_config_get_bool("uploadarchive.allowunreachable", &remote_allow_unreachable);
519         git_config(git_default_config, NULL);
520
521         init_tar_archiver();
522         init_zip_archiver();
523
524         argc = parse_archive_args(argc, argv, &ar, &args, name_hint, remote);
525         if (!startup_info->have_repository) {
526                 /*
527                  * We know this will die() with an error, so we could just
528                  * die ourselves; but its error message will be more specific
529                  * than what we could write here.
530                  */
531                 setup_git_directory();
532         }
533
534         parse_treeish_arg(argv, &args, prefix, remote);
535         parse_pathspec_arg(argv + 1, &args);
536
537         return ar->write_archive(ar, &args);
538 }
539
540 static int match_extension(const char *filename, const char *ext)
541 {
542         int prefixlen = strlen(filename) - strlen(ext);
543
544         /*
545          * We need 1 character for the '.', and 1 character to ensure that the
546          * prefix is non-empty (k.e., we don't match .tar.gz with no actual
547          * filename).
548          */
549         if (prefixlen < 2 || filename[prefixlen - 1] != '.')
550                 return 0;
551         return !strcmp(filename + prefixlen, ext);
552 }
553
554 const char *archive_format_from_filename(const char *filename)
555 {
556         int i;
557
558         for (i = 0; i < nr_archivers; i++)
559                 if (match_extension(filename, archivers[i]->name))
560                         return archivers[i]->name;
561         return NULL;
562 }