Code

archive: don't let remote clients get unreachable commits
[git.git] / archive.c
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"
8 static char const * const archive_usage[] = {
9         "git archive [options] <tree-ish> [path...]",
10         "git archive --list",
11         "git archive --remote <repo> [--exec <cmd>] [options] <tree-ish> [path...]",
12         "git archive --remote <repo> [--exec <cmd>] --list",
13         NULL
14 };
16 #define USES_ZLIB_COMPRESSION 1
18 static const struct archiver {
19         const char *name;
20         write_archive_fn_t write_archive;
21         unsigned int flags;
22 } archivers[] = {
23         { "tar", write_tar_archive },
24         { "zip", write_zip_archive, USES_ZLIB_COMPRESSION },
25 };
27 static void format_subst(const struct commit *commit,
28                          const char *src, size_t len,
29                          struct strbuf *buf)
30 {
31         char *to_free = NULL;
32         struct strbuf fmt = STRBUF_INIT;
34         if (src == buf->buf)
35                 to_free = strbuf_detach(buf, NULL);
36         for (;;) {
37                 const char *b, *c;
39                 b = memmem(src, len, "$Format:", 8);
40                 if (!b)
41                         break;
42                 c = memchr(b + 8, '$', (src + len) - b - 8);
43                 if (!c)
44                         break;
46                 strbuf_reset(&fmt);
47                 strbuf_add(&fmt, b + 8, c - b - 8);
49                 strbuf_add(buf, src, b - src);
50                 format_commit_message(commit, fmt.buf, buf, DATE_NORMAL);
51                 len -= c + 1 - src;
52                 src  = c + 1;
53         }
54         strbuf_add(buf, src, len);
55         strbuf_release(&fmt);
56         free(to_free);
57 }
59 static void *sha1_file_to_archive(const char *path, const unsigned char *sha1,
60                 unsigned int mode, enum object_type *type,
61                 unsigned long *sizep, const struct commit *commit)
62 {
63         void *buffer;
65         buffer = read_sha1_file(sha1, type, sizep);
66         if (buffer && S_ISREG(mode)) {
67                 struct strbuf buf = STRBUF_INIT;
68                 size_t size = 0;
70                 strbuf_attach(&buf, buffer, *sizep, *sizep + 1);
71                 convert_to_working_tree(path, buf.buf, buf.len, &buf);
72                 if (commit)
73                         format_subst(commit, buf.buf, buf.len, &buf);
74                 buffer = strbuf_detach(&buf, &size);
75                 *sizep = size;
76         }
78         return buffer;
79 }
81 static void setup_archive_check(struct git_attr_check *check)
82 {
83         static struct git_attr *attr_export_ignore;
84         static struct git_attr *attr_export_subst;
86         if (!attr_export_ignore) {
87                 attr_export_ignore = git_attr("export-ignore", 13);
88                 attr_export_subst = git_attr("export-subst", 12);
89         }
90         check[0].attr = attr_export_ignore;
91         check[1].attr = attr_export_subst;
92 }
94 struct archiver_context {
95         struct archiver_args *args;
96         write_archive_entry_fn_t write_entry;
97 };
99 static int write_archive_entry(const unsigned char *sha1, const char *base,
100                 int baselen, const char *filename, unsigned mode, int stage,
101                 void *context)
103         static struct strbuf path = STRBUF_INIT;
104         struct archiver_context *c = context;
105         struct archiver_args *args = c->args;
106         write_archive_entry_fn_t write_entry = c->write_entry;
107         struct git_attr_check check[2];
108         const char *path_without_prefix;
109         int convert = 0;
110         int err;
111         enum object_type type;
112         unsigned long size;
113         void *buffer;
115         strbuf_reset(&path);
116         strbuf_grow(&path, PATH_MAX);
117         strbuf_add(&path, base, baselen);
118         strbuf_addstr(&path, filename);
119         path_without_prefix = path.buf + args->baselen;
121         setup_archive_check(check);
122         if (!git_checkattr(path_without_prefix, ARRAY_SIZE(check), check)) {
123                 if (ATTR_TRUE(check[0].value))
124                         return 0;
125                 convert = ATTR_TRUE(check[1].value);
126         }
128         if (S_ISDIR(mode) || S_ISGITLINK(mode)) {
129                 strbuf_addch(&path, '/');
130                 if (args->verbose)
131                         fprintf(stderr, "%.*s\n", (int)path.len, path.buf);
132                 err = write_entry(args, sha1, path.buf, path.len, mode, NULL, 0);
133                 if (err)
134                         return err;
135                 return (S_ISDIR(mode) ? READ_TREE_RECURSIVE : 0);
136         }
138         buffer = sha1_file_to_archive(path_without_prefix, sha1, mode,
139                         &type, &size, convert ? args->commit : NULL);
140         if (!buffer)
141                 return error("cannot read %s", sha1_to_hex(sha1));
142         if (args->verbose)
143                 fprintf(stderr, "%.*s\n", (int)path.len, path.buf);
144         err = write_entry(args, sha1, path.buf, path.len, mode, buffer, size);
145         free(buffer);
146         return err;
149 int write_archive_entries(struct archiver_args *args,
150                 write_archive_entry_fn_t write_entry)
152         struct archiver_context context;
153         int err;
155         if (args->baselen > 0 && args->base[args->baselen - 1] == '/') {
156                 size_t len = args->baselen;
158                 while (len > 1 && args->base[len - 2] == '/')
159                         len--;
160                 if (args->verbose)
161                         fprintf(stderr, "%.*s\n", (int)len, args->base);
162                 err = write_entry(args, args->tree->object.sha1, args->base,
163                                 len, 040777, NULL, 0);
164                 if (err)
165                         return err;
166         }
168         context.args = args;
169         context.write_entry = write_entry;
171         err =  read_tree_recursive(args->tree, args->base, args->baselen, 0,
172                         args->pathspec, write_archive_entry, &context);
173         if (err == READ_TREE_RECURSIVE)
174                 err = 0;
175         return err;
178 static const struct archiver *lookup_archiver(const char *name)
180         int i;
182         if (!name)
183                 return NULL;
185         for (i = 0; i < ARRAY_SIZE(archivers); i++) {
186                 if (!strcmp(name, archivers[i].name))
187                         return &archivers[i];
188         }
189         return NULL;
192 static void parse_pathspec_arg(const char **pathspec,
193                 struct archiver_args *ar_args)
195         ar_args->pathspec = get_pathspec(ar_args->base, pathspec);
198 static void parse_treeish_arg(const char **argv,
199                 struct archiver_args *ar_args, const char *prefix,
200                 int remote)
202         const char *name = argv[0];
203         const unsigned char *commit_sha1;
204         time_t archive_time;
205         struct tree *tree;
206         const struct commit *commit;
207         unsigned char sha1[20];
209         /* Remotes are only allowed to fetch actual refs */
210         if (remote) {
211                 char *ref = NULL;
212                 if (!dwim_ref(name, strlen(name), sha1, &ref))
213                         die("no such ref: %s", name);
214                 free(ref);
215         }
216         else {
217                 if (get_sha1(name, sha1))
218                         die("Not a valid object name");
219         }
221         commit = lookup_commit_reference_gently(sha1, 1);
222         if (commit) {
223                 commit_sha1 = commit->object.sha1;
224                 archive_time = commit->date;
225         } else {
226                 commit_sha1 = NULL;
227                 archive_time = time(NULL);
228         }
230         tree = parse_tree_indirect(sha1);
231         if (tree == NULL)
232                 die("not a tree object");
234         if (prefix) {
235                 unsigned char tree_sha1[20];
236                 unsigned int mode;
237                 int err;
239                 err = get_tree_entry(tree->object.sha1, prefix,
240                                      tree_sha1, &mode);
241                 if (err || !S_ISDIR(mode))
242                         die("current working directory is untracked");
244                 tree = parse_tree_indirect(tree_sha1);
245         }
246         ar_args->tree = tree;
247         ar_args->commit_sha1 = commit_sha1;
248         ar_args->commit = commit;
249         ar_args->time = archive_time;
252 #define OPT__COMPR(s, v, h, p) \
253         { OPTION_SET_INT, (s), NULL, (v), NULL, (h), \
254           PARSE_OPT_NOARG | PARSE_OPT_NONEG, NULL, (p) }
255 #define OPT__COMPR_HIDDEN(s, v, p) \
256         { OPTION_SET_INT, (s), NULL, (v), NULL, "", \
257           PARSE_OPT_NOARG | PARSE_OPT_NONEG | PARSE_OPT_HIDDEN, NULL, (p) }
259 static int parse_archive_args(int argc, const char **argv,
260                 const struct archiver **ar, struct archiver_args *args)
262         const char *format = "tar";
263         const char *base = NULL;
264         const char *remote = NULL;
265         const char *exec = NULL;
266         int compression_level = -1;
267         int verbose = 0;
268         int i;
269         int list = 0;
270         struct option opts[] = {
271                 OPT_GROUP(""),
272                 OPT_STRING(0, "format", &format, "fmt", "archive format"),
273                 OPT_STRING(0, "prefix", &base, "prefix",
274                         "prepend prefix to each pathname in the archive"),
275                 OPT__VERBOSE(&verbose),
276                 OPT__COMPR('0', &compression_level, "store only", 0),
277                 OPT__COMPR('1', &compression_level, "compress faster", 1),
278                 OPT__COMPR_HIDDEN('2', &compression_level, 2),
279                 OPT__COMPR_HIDDEN('3', &compression_level, 3),
280                 OPT__COMPR_HIDDEN('4', &compression_level, 4),
281                 OPT__COMPR_HIDDEN('5', &compression_level, 5),
282                 OPT__COMPR_HIDDEN('6', &compression_level, 6),
283                 OPT__COMPR_HIDDEN('7', &compression_level, 7),
284                 OPT__COMPR_HIDDEN('8', &compression_level, 8),
285                 OPT__COMPR('9', &compression_level, "compress better", 9),
286                 OPT_GROUP(""),
287                 OPT_BOOLEAN('l', "list", &list,
288                         "list supported archive formats"),
289                 OPT_GROUP(""),
290                 OPT_STRING(0, "remote", &remote, "repo",
291                         "retrieve the archive from remote repository <repo>"),
292                 OPT_STRING(0, "exec", &exec, "cmd",
293                         "path to the remote git-upload-archive command"),
294                 OPT_END()
295         };
297         argc = parse_options(argc, argv, opts, archive_usage, 0);
299         if (remote)
300                 die("Unexpected option --remote");
301         if (exec)
302                 die("Option --exec can only be used together with --remote");
304         if (!base)
305                 base = "";
307         if (list) {
308                 for (i = 0; i < ARRAY_SIZE(archivers); i++)
309                         printf("%s\n", archivers[i].name);
310                 exit(0);
311         }
313         /* We need at least one parameter -- tree-ish */
314         if (argc < 1)
315                 usage_with_options(archive_usage, opts);
316         *ar = lookup_archiver(format);
317         if (!*ar)
318                 die("Unknown archive format '%s'", format);
320         args->compression_level = Z_DEFAULT_COMPRESSION;
321         if (compression_level != -1) {
322                 if ((*ar)->flags & USES_ZLIB_COMPRESSION)
323                         args->compression_level = compression_level;
324                 else {
325                         die("Argument not supported for format '%s': -%d",
326                                         format, compression_level);
327                 }
328         }
329         args->verbose = verbose;
330         args->base = base;
331         args->baselen = strlen(base);
333         return argc;
336 int write_archive(int argc, const char **argv, const char *prefix,
337                   int setup_prefix, int remote)
339         const struct archiver *ar = NULL;
340         struct archiver_args args;
342         argc = parse_archive_args(argc, argv, &ar, &args);
343         if (setup_prefix && prefix == NULL)
344                 prefix = setup_git_directory();
346         parse_treeish_arg(argv, &args, prefix, remote);
347         parse_pathspec_arg(argv + 1, &args);
349         git_config(git_default_config, NULL);
351         return ar->write_archive(&args);