2 * Copyright (c) 2005, 2006 Rene Scharfe
9 #include "run-command.h"
11 #define RECORDSIZE (512)
12 #define BLOCKSIZE (RECORDSIZE * 20)
14 static char block
[BLOCKSIZE
];
15 static unsigned long offset
;
17 static int tar_umask
= 002;
19 static int write_tar_filter_archive(const struct archiver
*ar
,
20 struct archiver_args
*args
);
23 * This is the max value that a ustar size header can specify, as it is fixed
24 * at 11 octal digits. POSIX specifies that we switch to extended headers at
27 * Likewise for the mtime (which happens to use a buffer of the same size).
29 #if ULONG_MAX == 0xFFFFFFFF
30 #define USTAR_MAX_SIZE ULONG_MAX
32 #define USTAR_MAX_SIZE 077777777777UL
34 #if TIME_MAX == 0xFFFFFFFF
35 #define USTAR_MAX_MTIME TIME_MAX
37 #define USTAR_MAX_MTIME 077777777777ULL
40 /* writes out the whole block, but only if it is full */
41 static void write_if_needed(void)
43 if (offset
== BLOCKSIZE
) {
44 write_or_die(1, block
, BLOCKSIZE
);
50 * queues up writes, so that all our write(2) calls write exactly one
51 * full block; pads writes to RECORDSIZE
53 static void do_write_blocked(const void *data
, unsigned long size
)
55 const char *buf
= data
;
58 unsigned long chunk
= BLOCKSIZE
- offset
;
61 memcpy(block
+ offset
, buf
, chunk
);
67 while (size
>= BLOCKSIZE
) {
68 write_or_die(1, buf
, BLOCKSIZE
);
73 memcpy(block
+ offset
, buf
, size
);
78 static void finish_record(void)
81 tail
= offset
% RECORDSIZE
;
83 memset(block
+ offset
, 0, RECORDSIZE
- tail
);
84 offset
+= RECORDSIZE
- tail
;
89 static void write_blocked(const void *data
, unsigned long size
)
91 do_write_blocked(data
, size
);
96 * The end of tar archives is marked by 2*512 nul bytes and after that
97 * follows the rest of the block (if any).
99 static void write_trailer(void)
101 int tail
= BLOCKSIZE
- offset
;
102 memset(block
+ offset
, 0, tail
);
103 write_or_die(1, block
, BLOCKSIZE
);
104 if (tail
< 2 * RECORDSIZE
) {
105 memset(block
, 0, offset
);
106 write_or_die(1, block
, BLOCKSIZE
);
111 * queues up writes, so that all our write(2) calls write exactly one
112 * full block; pads writes to RECORDSIZE
114 static int stream_blocked(const struct object_id
*oid
)
116 struct git_istream
*st
;
117 enum object_type type
;
122 st
= open_istream(oid
, &type
, &sz
, NULL
);
124 return error("cannot stream blob %s", oid_to_hex(oid
));
126 readlen
= read_istream(st
, buf
, sizeof(buf
));
129 do_write_blocked(buf
, readlen
);
138 * pax extended header records have the format "%u %s=%s\n". %u contains
139 * the size of the whole string (including the %u), the first %s is the
140 * keyword, the second one is the value. This function constructs such a
141 * string and appends it to a struct strbuf.
143 static void strbuf_append_ext_header(struct strbuf
*sb
, const char *keyword
,
144 const char *value
, unsigned int valuelen
)
149 len
= 1 + 1 + strlen(keyword
) + 1 + valuelen
+ 1;
150 for (tmp
= len
; tmp
> 9; tmp
/= 10)
153 strbuf_grow(sb
, len
);
154 strbuf_addf(sb
, "%u %s=", len
, keyword
);
155 strbuf_add(sb
, value
, valuelen
);
156 strbuf_addch(sb
, '\n');
160 * Like strbuf_append_ext_header, but for numeric values.
162 static void strbuf_append_ext_header_uint(struct strbuf
*sb
,
166 char buf
[40]; /* big enough for 2^128 in decimal, plus NUL */
169 len
= xsnprintf(buf
, sizeof(buf
), "%"PRIuMAX
, value
);
170 strbuf_append_ext_header(sb
, keyword
, buf
, len
);
173 static unsigned int ustar_header_chksum(const struct ustar_header
*header
)
175 const unsigned char *p
= (const unsigned char *)header
;
176 unsigned int chksum
= 0;
177 while (p
< (const unsigned char *)header
->chksum
)
179 chksum
+= sizeof(header
->chksum
) * ' ';
180 p
+= sizeof(header
->chksum
);
181 while (p
< (const unsigned char *)header
+ sizeof(struct ustar_header
))
186 static size_t get_path_prefix(const char *path
, size_t pathlen
, size_t maxlen
)
189 if (i
> 1 && path
[i
- 1] == '/')
195 } while (i
> 0 && path
[i
] != '/');
199 static void prepare_header(struct archiver_args
*args
,
200 struct ustar_header
*header
,
201 unsigned int mode
, unsigned long size
)
203 xsnprintf(header
->mode
, sizeof(header
->mode
), "%07o", mode
& 07777);
204 xsnprintf(header
->size
, sizeof(header
->size
), "%011lo", S_ISREG(mode
) ? size
: 0);
205 xsnprintf(header
->mtime
, sizeof(header
->mtime
), "%011lo", (unsigned long) args
->time
);
207 xsnprintf(header
->uid
, sizeof(header
->uid
), "%07o", 0);
208 xsnprintf(header
->gid
, sizeof(header
->gid
), "%07o", 0);
209 strlcpy(header
->uname
, "root", sizeof(header
->uname
));
210 strlcpy(header
->gname
, "root", sizeof(header
->gname
));
211 xsnprintf(header
->devmajor
, sizeof(header
->devmajor
), "%07o", 0);
212 xsnprintf(header
->devminor
, sizeof(header
->devminor
), "%07o", 0);
214 memcpy(header
->magic
, "ustar", 6);
215 memcpy(header
->version
, "00", 2);
217 xsnprintf(header
->chksum
, sizeof(header
->chksum
), "%07o", ustar_header_chksum(header
));
220 static void write_extended_header(struct archiver_args
*args
,
221 const struct object_id
*oid
,
222 const void *buffer
, unsigned long size
)
224 struct ustar_header header
;
226 memset(&header
, 0, sizeof(header
));
227 *header
.typeflag
= TYPEFLAG_EXT_HEADER
;
229 xsnprintf(header
.name
, sizeof(header
.name
), "%s.paxheader", oid_to_hex(oid
));
230 prepare_header(args
, &header
, mode
, size
);
231 write_blocked(&header
, sizeof(header
));
232 write_blocked(buffer
, size
);
235 static int write_tar_entry(struct archiver_args
*args
,
236 const struct object_id
*oid
,
237 const char *path
, size_t pathlen
,
240 struct ustar_header header
;
241 struct strbuf ext_header
= STRBUF_INIT
;
242 unsigned int old_mode
= mode
;
243 unsigned long size
, size_in_header
;
247 memset(&header
, 0, sizeof(header
));
249 if (S_ISDIR(mode
) || S_ISGITLINK(mode
)) {
250 *header
.typeflag
= TYPEFLAG_DIR
;
251 mode
= (mode
| 0777) & ~tar_umask
;
252 } else if (S_ISLNK(mode
)) {
253 *header
.typeflag
= TYPEFLAG_LNK
;
255 } else if (S_ISREG(mode
)) {
256 *header
.typeflag
= TYPEFLAG_REG
;
257 mode
= (mode
| ((mode
& 0100) ? 0777 : 0666)) & ~tar_umask
;
259 return error("unsupported file mode: 0%o (SHA1: %s)",
260 mode
, oid_to_hex(oid
));
262 if (pathlen
> sizeof(header
.name
)) {
263 size_t plen
= get_path_prefix(path
, pathlen
,
264 sizeof(header
.prefix
));
265 size_t rest
= pathlen
- plen
- 1;
266 if (plen
> 0 && rest
<= sizeof(header
.name
)) {
267 memcpy(header
.prefix
, path
, plen
);
268 memcpy(header
.name
, path
+ plen
+ 1, rest
);
270 xsnprintf(header
.name
, sizeof(header
.name
), "%s.data",
272 strbuf_append_ext_header(&ext_header
, "path",
276 memcpy(header
.name
, path
, pathlen
);
278 if (S_ISREG(mode
) && !args
->convert
&&
279 oid_object_info(the_repository
, oid
, &size
) == OBJ_BLOB
&&
280 size
> big_file_threshold
)
282 else if (S_ISLNK(mode
) || S_ISREG(mode
)) {
283 enum object_type type
;
284 buffer
= object_file_to_archive(args
, path
, oid
, old_mode
, &type
, &size
);
286 return error("cannot read %s", oid_to_hex(oid
));
293 if (size
> sizeof(header
.linkname
)) {
294 xsnprintf(header
.linkname
, sizeof(header
.linkname
),
295 "see %s.paxheader", oid_to_hex(oid
));
296 strbuf_append_ext_header(&ext_header
, "linkpath",
299 memcpy(header
.linkname
, buffer
, size
);
302 size_in_header
= size
;
303 if (S_ISREG(mode
) && size
> USTAR_MAX_SIZE
) {
305 strbuf_append_ext_header_uint(&ext_header
, "size", size
);
308 prepare_header(args
, &header
, mode
, size_in_header
);
310 if (ext_header
.len
> 0) {
311 write_extended_header(args
, oid
, ext_header
.buf
,
314 strbuf_release(&ext_header
);
315 write_blocked(&header
, sizeof(header
));
316 if (S_ISREG(mode
) && size
> 0) {
318 write_blocked(buffer
, size
);
320 err
= stream_blocked(oid
);
326 static void write_global_extended_header(struct archiver_args
*args
)
328 const unsigned char *sha1
= args
->commit_sha1
;
329 struct strbuf ext_header
= STRBUF_INIT
;
330 struct ustar_header header
;
334 strbuf_append_ext_header(&ext_header
, "comment",
335 sha1_to_hex(sha1
), 40);
336 if (args
->time
> USTAR_MAX_MTIME
) {
337 strbuf_append_ext_header_uint(&ext_header
, "mtime",
339 args
->time
= USTAR_MAX_MTIME
;
345 memset(&header
, 0, sizeof(header
));
346 *header
.typeflag
= TYPEFLAG_GLOBAL_HEADER
;
348 xsnprintf(header
.name
, sizeof(header
.name
), "pax_global_header");
349 prepare_header(args
, &header
, mode
, ext_header
.len
);
350 write_blocked(&header
, sizeof(header
));
351 write_blocked(ext_header
.buf
, ext_header
.len
);
352 strbuf_release(&ext_header
);
355 static struct archiver
**tar_filters
;
356 static int nr_tar_filters
;
357 static int alloc_tar_filters
;
359 static struct archiver
*find_tar_filter(const char *name
, int len
)
362 for (i
= 0; i
< nr_tar_filters
; i
++) {
363 struct archiver
*ar
= tar_filters
[i
];
364 if (!strncmp(ar
->name
, name
, len
) && !ar
->name
[len
])
370 static int tar_filter_config(const char *var
, const char *value
, void *data
)
377 if (parse_config_key(var
, "tar", &name
, &namelen
, &type
) < 0 || !name
)
380 ar
= find_tar_filter(name
, namelen
);
382 ar
= xcalloc(1, sizeof(*ar
));
383 ar
->name
= xmemdupz(name
, namelen
);
384 ar
->write_archive
= write_tar_filter_archive
;
385 ar
->flags
= ARCHIVER_WANT_COMPRESSION_LEVELS
;
386 ALLOC_GROW(tar_filters
, nr_tar_filters
+ 1, alloc_tar_filters
);
387 tar_filters
[nr_tar_filters
++] = ar
;
390 if (!strcmp(type
, "command")) {
392 return config_error_nonbool(var
);
394 ar
->data
= xstrdup(value
);
397 if (!strcmp(type
, "remote")) {
398 if (git_config_bool(var
, value
))
399 ar
->flags
|= ARCHIVER_REMOTE
;
401 ar
->flags
&= ~ARCHIVER_REMOTE
;
408 static int git_tar_config(const char *var
, const char *value
, void *cb
)
410 if (!strcmp(var
, "tar.umask")) {
411 if (value
&& !strcmp(value
, "user")) {
412 tar_umask
= umask(0);
415 tar_umask
= git_config_int(var
, value
);
420 return tar_filter_config(var
, value
, cb
);
423 static int write_tar_archive(const struct archiver
*ar
,
424 struct archiver_args
*args
)
428 write_global_extended_header(args
);
429 err
= write_archive_entries(args
, write_tar_entry
);
435 static int write_tar_filter_archive(const struct archiver
*ar
,
436 struct archiver_args
*args
)
438 struct strbuf cmd
= STRBUF_INIT
;
439 struct child_process filter
= CHILD_PROCESS_INIT
;
444 BUG("tar-filter archiver called with no filter defined");
446 strbuf_addstr(&cmd
, ar
->data
);
447 if (args
->compression_level
>= 0)
448 strbuf_addf(&cmd
, " -%d", args
->compression_level
);
453 filter
.use_shell
= 1;
456 if (start_command(&filter
) < 0)
457 die_errno("unable to start '%s' filter", argv
[0]);
459 if (dup2(filter
.in
, 1) < 0)
460 die_errno("unable to redirect descriptor");
463 r
= write_tar_archive(ar
, args
);
466 if (finish_command(&filter
) != 0)
467 die("'%s' filter reported error", argv
[0]);
469 strbuf_release(&cmd
);
473 static struct archiver tar_archiver
= {
479 void init_tar_archiver(void)
482 register_archiver(&tar_archiver
);
484 tar_filter_config("tar.tgz.command", "gzip -cn", NULL
);
485 tar_filter_config("tar.tgz.remote", "true", NULL
);
486 tar_filter_config("tar.tar.gz.command", "gzip -cn", NULL
);
487 tar_filter_config("tar.tar.gz.remote", "true", NULL
);
488 git_config(git_tar_config
, NULL
);
489 for (i
= 0; i
< nr_tar_filters
; i
++) {
490 /* omit any filters that never had a command configured */
491 if (tar_filters
[i
]->data
)
492 register_archiver(tar_filters
[i
]);