]>
Commit | Line | Data |
---|---|---|
46bf0438 JH |
1 | /* |
2 | * Copyright (c) 2011, Google Inc. | |
3 | */ | |
4 | #include "cache.h" | |
5 | #include "streaming.h" | |
84f80ad5 | 6 | #include "packfile.h" |
46bf0438 JH |
7 | |
8 | enum input_source { | |
9 | stream_error = -1, | |
10 | incore = 0, | |
11 | loose = 1, | |
12 | pack_non_delta = 2 | |
13 | }; | |
14 | ||
15 | typedef int (*open_istream_fn)(struct git_istream *, | |
16 | struct object_info *, | |
17 | const unsigned char *, | |
18 | enum object_type *); | |
19 | typedef int (*close_istream_fn)(struct git_istream *); | |
20 | typedef ssize_t (*read_istream_fn)(struct git_istream *, char *, size_t); | |
21 | ||
22 | struct stream_vtbl { | |
23 | close_istream_fn close; | |
24 | read_istream_fn read; | |
25 | }; | |
26 | ||
27 | #define open_method_decl(name) \ | |
28 | int open_istream_ ##name \ | |
29 | (struct git_istream *st, struct object_info *oi, \ | |
30 | const unsigned char *sha1, \ | |
31 | enum object_type *type) | |
32 | ||
33 | #define close_method_decl(name) \ | |
34 | int close_istream_ ##name \ | |
35 | (struct git_istream *st) | |
36 | ||
37 | #define read_method_decl(name) \ | |
38 | ssize_t read_istream_ ##name \ | |
39 | (struct git_istream *st, char *buf, size_t sz) | |
40 | ||
41 | /* forward declaration */ | |
42 | static open_method_decl(incore); | |
43 | static open_method_decl(loose); | |
44 | static open_method_decl(pack_non_delta); | |
b6691092 JH |
45 | static struct git_istream *attach_stream_filter(struct git_istream *st, |
46 | struct stream_filter *filter); | |
47 | ||
46bf0438 JH |
48 | |
49 | static open_istream_fn open_istream_tbl[] = { | |
50 | open_istream_incore, | |
51 | open_istream_loose, | |
52 | open_istream_pack_non_delta, | |
53 | }; | |
54 | ||
b6691092 JH |
55 | #define FILTER_BUFFER (1024*16) |
56 | ||
57 | struct filtered_istream { | |
58 | struct git_istream *upstream; | |
59 | struct stream_filter *filter; | |
60 | char ibuf[FILTER_BUFFER]; | |
61 | char obuf[FILTER_BUFFER]; | |
62 | int i_end, i_ptr; | |
63 | int o_end, o_ptr; | |
4ae66704 | 64 | int input_finished; |
b6691092 JH |
65 | }; |
66 | ||
46bf0438 JH |
67 | struct git_istream { |
68 | const struct stream_vtbl *vtbl; | |
69 | unsigned long size; /* inflated size of full object */ | |
eb4f4076 | 70 | git_zstream z; |
7ef2d9a2 | 71 | enum { z_unused, z_used, z_done, z_error } z_state; |
46bf0438 JH |
72 | |
73 | union { | |
74 | struct { | |
75 | char *buf; /* from read_object() */ | |
76 | unsigned long read_ptr; | |
77 | } incore; | |
78 | ||
79 | struct { | |
93aa7bd5 JH |
80 | void *mapped; |
81 | unsigned long mapsize; | |
82 | char hdr[32]; | |
83 | int hdr_avail; | |
84 | int hdr_used; | |
46bf0438 JH |
85 | } loose; |
86 | ||
87 | struct { | |
7ef2d9a2 JH |
88 | struct packed_git *pack; |
89 | off_t pos; | |
46bf0438 | 90 | } in_pack; |
b6691092 JH |
91 | |
92 | struct filtered_istream filtered; | |
46bf0438 JH |
93 | } u; |
94 | }; | |
95 | ||
96 | int close_istream(struct git_istream *st) | |
97 | { | |
95dea6eb JK |
98 | int r = st->vtbl->close(st); |
99 | free(st); | |
100 | return r; | |
46bf0438 JH |
101 | } |
102 | ||
6163cd8a | 103 | ssize_t read_istream(struct git_istream *st, void *buf, size_t sz) |
46bf0438 JH |
104 | { |
105 | return st->vtbl->read(st, buf, sz); | |
106 | } | |
107 | ||
108 | static enum input_source istream_source(const unsigned char *sha1, | |
109 | enum object_type *type, | |
110 | struct object_info *oi) | |
111 | { | |
112 | unsigned long size; | |
113 | int status; | |
114 | ||
5b086407 | 115 | oi->typep = type; |
46bf0438 | 116 | oi->sizep = &size; |
de7b5d62 | 117 | status = sha1_object_info_extended(sha1, oi, 0); |
46bf0438 JH |
118 | if (status < 0) |
119 | return stream_error; | |
46bf0438 JH |
120 | |
121 | switch (oi->whence) { | |
122 | case OI_LOOSE: | |
123 | return loose; | |
124 | case OI_PACKED: | |
754980d0 | 125 | if (!oi->u.packed.is_delta && big_file_threshold < size) |
46bf0438 JH |
126 | return pack_non_delta; |
127 | /* fallthru */ | |
128 | default: | |
129 | return incore; | |
130 | } | |
131 | } | |
132 | ||
133 | struct git_istream *open_istream(const unsigned char *sha1, | |
134 | enum object_type *type, | |
b6691092 JH |
135 | unsigned long *size, |
136 | struct stream_filter *filter) | |
46bf0438 JH |
137 | { |
138 | struct git_istream *st; | |
27b5c1a0 | 139 | struct object_info oi = OBJECT_INFO_INIT; |
46bf0438 JH |
140 | const unsigned char *real = lookup_replace_object(sha1); |
141 | enum input_source src = istream_source(real, type, &oi); | |
142 | ||
143 | if (src < 0) | |
144 | return NULL; | |
145 | ||
146 | st = xmalloc(sizeof(*st)); | |
147 | if (open_istream_tbl[src](st, &oi, real, type)) { | |
148 | if (open_istream_incore(st, &oi, real, type)) { | |
149 | free(st); | |
150 | return NULL; | |
151 | } | |
152 | } | |
6a907786 | 153 | if (filter) { |
b6691092 JH |
154 | /* Add "&& !is_null_stream_filter(filter)" for performance */ |
155 | struct git_istream *nst = attach_stream_filter(st, filter); | |
78368f2c | 156 | if (!nst) { |
b6691092 | 157 | close_istream(st); |
78368f2c JH |
158 | return NULL; |
159 | } | |
b6691092 JH |
160 | st = nst; |
161 | } | |
162 | ||
46bf0438 JH |
163 | *size = st->size; |
164 | return st; | |
165 | } | |
166 | ||
7ef2d9a2 JH |
167 | |
168 | /***************************************************************** | |
169 | * | |
170 | * Common helpers | |
171 | * | |
172 | *****************************************************************/ | |
173 | ||
174 | static void close_deflated_stream(struct git_istream *st) | |
175 | { | |
176 | if (st->z_state == z_used) | |
177 | git_inflate_end(&st->z); | |
178 | } | |
179 | ||
180 | ||
b6691092 JH |
181 | /***************************************************************** |
182 | * | |
183 | * Filtered stream | |
184 | * | |
185 | *****************************************************************/ | |
186 | ||
187 | static close_method_decl(filtered) | |
188 | { | |
189 | free_stream_filter(st->u.filtered.filter); | |
190 | return close_istream(st->u.filtered.upstream); | |
191 | } | |
192 | ||
193 | static read_method_decl(filtered) | |
194 | { | |
195 | struct filtered_istream *fs = &(st->u.filtered); | |
196 | size_t filled = 0; | |
197 | ||
198 | while (sz) { | |
199 | /* do we already have filtered output? */ | |
200 | if (fs->o_ptr < fs->o_end) { | |
201 | size_t to_move = fs->o_end - fs->o_ptr; | |
202 | if (sz < to_move) | |
203 | to_move = sz; | |
204 | memcpy(buf + filled, fs->obuf + fs->o_ptr, to_move); | |
205 | fs->o_ptr += to_move; | |
206 | sz -= to_move; | |
207 | filled += to_move; | |
208 | continue; | |
209 | } | |
210 | fs->o_end = fs->o_ptr = 0; | |
211 | ||
212 | /* do we have anything to feed the filter with? */ | |
213 | if (fs->i_ptr < fs->i_end) { | |
214 | size_t to_feed = fs->i_end - fs->i_ptr; | |
215 | size_t to_receive = FILTER_BUFFER; | |
216 | if (stream_filter(fs->filter, | |
217 | fs->ibuf + fs->i_ptr, &to_feed, | |
218 | fs->obuf, &to_receive)) | |
219 | return -1; | |
220 | fs->i_ptr = fs->i_end - to_feed; | |
221 | fs->o_end = FILTER_BUFFER - to_receive; | |
222 | continue; | |
223 | } | |
4ae66704 JH |
224 | |
225 | /* tell the filter to drain upon no more input */ | |
226 | if (fs->input_finished) { | |
227 | size_t to_receive = FILTER_BUFFER; | |
228 | if (stream_filter(fs->filter, | |
229 | NULL, NULL, | |
230 | fs->obuf, &to_receive)) | |
231 | return -1; | |
232 | fs->o_end = FILTER_BUFFER - to_receive; | |
233 | if (!fs->o_end) | |
234 | break; | |
235 | continue; | |
236 | } | |
b6691092 JH |
237 | fs->i_end = fs->i_ptr = 0; |
238 | ||
239 | /* refill the input from the upstream */ | |
4ae66704 JH |
240 | if (!fs->input_finished) { |
241 | fs->i_end = read_istream(fs->upstream, fs->ibuf, FILTER_BUFFER); | |
242 | if (fs->i_end < 0) | |
42e7e2a5 | 243 | return -1; |
4ae66704 JH |
244 | if (fs->i_end) |
245 | continue; | |
246 | } | |
247 | fs->input_finished = 1; | |
b6691092 JH |
248 | } |
249 | return filled; | |
250 | } | |
251 | ||
252 | static struct stream_vtbl filtered_vtbl = { | |
253 | close_istream_filtered, | |
254 | read_istream_filtered, | |
255 | }; | |
256 | ||
257 | static struct git_istream *attach_stream_filter(struct git_istream *st, | |
258 | struct stream_filter *filter) | |
259 | { | |
260 | struct git_istream *ifs = xmalloc(sizeof(*ifs)); | |
261 | struct filtered_istream *fs = &(ifs->u.filtered); | |
262 | ||
263 | ifs->vtbl = &filtered_vtbl; | |
264 | fs->upstream = st; | |
265 | fs->filter = filter; | |
266 | fs->i_end = fs->i_ptr = 0; | |
267 | fs->o_end = fs->o_ptr = 0; | |
4ae66704 | 268 | fs->input_finished = 0; |
b6691092 JH |
269 | ifs->size = -1; /* unknown */ |
270 | return ifs; | |
271 | } | |
272 | ||
46bf0438 JH |
273 | /***************************************************************** |
274 | * | |
275 | * Loose object stream | |
276 | * | |
277 | *****************************************************************/ | |
278 | ||
93aa7bd5 JH |
279 | static read_method_decl(loose) |
280 | { | |
281 | size_t total_read = 0; | |
282 | ||
283 | switch (st->z_state) { | |
284 | case z_done: | |
285 | return 0; | |
286 | case z_error: | |
287 | return -1; | |
288 | default: | |
289 | break; | |
290 | } | |
291 | ||
292 | if (st->u.loose.hdr_used < st->u.loose.hdr_avail) { | |
293 | size_t to_copy = st->u.loose.hdr_avail - st->u.loose.hdr_used; | |
294 | if (sz < to_copy) | |
295 | to_copy = sz; | |
296 | memcpy(buf, st->u.loose.hdr + st->u.loose.hdr_used, to_copy); | |
297 | st->u.loose.hdr_used += to_copy; | |
298 | total_read += to_copy; | |
299 | } | |
300 | ||
301 | while (total_read < sz) { | |
302 | int status; | |
303 | ||
304 | st->z.next_out = (unsigned char *)buf + total_read; | |
305 | st->z.avail_out = sz - total_read; | |
306 | status = git_inflate(&st->z, Z_FINISH); | |
307 | ||
308 | total_read = st->z.next_out - (unsigned char *)buf; | |
309 | ||
310 | if (status == Z_STREAM_END) { | |
311 | git_inflate_end(&st->z); | |
312 | st->z_state = z_done; | |
313 | break; | |
314 | } | |
692f0bc7 | 315 | if (status != Z_OK && (status != Z_BUF_ERROR || total_read < sz)) { |
93aa7bd5 JH |
316 | git_inflate_end(&st->z); |
317 | st->z_state = z_error; | |
318 | return -1; | |
319 | } | |
320 | } | |
321 | return total_read; | |
322 | } | |
323 | ||
324 | static close_method_decl(loose) | |
325 | { | |
326 | close_deflated_stream(st); | |
327 | munmap(st->u.loose.mapped, st->u.loose.mapsize); | |
328 | return 0; | |
329 | } | |
330 | ||
331 | static struct stream_vtbl loose_vtbl = { | |
332 | close_istream_loose, | |
333 | read_istream_loose, | |
334 | }; | |
335 | ||
46bf0438 JH |
336 | static open_method_decl(loose) |
337 | { | |
93aa7bd5 JH |
338 | st->u.loose.mapped = map_sha1_file(sha1, &st->u.loose.mapsize); |
339 | if (!st->u.loose.mapped) | |
340 | return -1; | |
97026fe9 JH |
341 | if ((unpack_sha1_header(&st->z, |
342 | st->u.loose.mapped, | |
343 | st->u.loose.mapsize, | |
344 | st->u.loose.hdr, | |
345 | sizeof(st->u.loose.hdr)) < 0) || | |
346 | (parse_sha1_header(st->u.loose.hdr, &st->size) < 0)) { | |
93aa7bd5 JH |
347 | git_inflate_end(&st->z); |
348 | munmap(st->u.loose.mapped, st->u.loose.mapsize); | |
349 | return -1; | |
350 | } | |
351 | ||
93aa7bd5 JH |
352 | st->u.loose.hdr_used = strlen(st->u.loose.hdr) + 1; |
353 | st->u.loose.hdr_avail = st->z.total_out; | |
354 | st->z_state = z_used; | |
355 | ||
356 | st->vtbl = &loose_vtbl; | |
357 | return 0; | |
46bf0438 JH |
358 | } |
359 | ||
360 | ||
361 | /***************************************************************** | |
362 | * | |
363 | * Non-delta packed object stream | |
364 | * | |
365 | *****************************************************************/ | |
366 | ||
7ef2d9a2 JH |
367 | static read_method_decl(pack_non_delta) |
368 | { | |
369 | size_t total_read = 0; | |
370 | ||
371 | switch (st->z_state) { | |
372 | case z_unused: | |
373 | memset(&st->z, 0, sizeof(st->z)); | |
374 | git_inflate_init(&st->z); | |
375 | st->z_state = z_used; | |
376 | break; | |
377 | case z_done: | |
378 | return 0; | |
379 | case z_error: | |
380 | return -1; | |
381 | case z_used: | |
382 | break; | |
383 | } | |
384 | ||
385 | while (total_read < sz) { | |
386 | int status; | |
387 | struct pack_window *window = NULL; | |
388 | unsigned char *mapped; | |
389 | ||
390 | mapped = use_pack(st->u.in_pack.pack, &window, | |
391 | st->u.in_pack.pos, &st->z.avail_in); | |
392 | ||
393 | st->z.next_out = (unsigned char *)buf + total_read; | |
394 | st->z.avail_out = sz - total_read; | |
395 | st->z.next_in = mapped; | |
396 | status = git_inflate(&st->z, Z_FINISH); | |
397 | ||
398 | st->u.in_pack.pos += st->z.next_in - mapped; | |
399 | total_read = st->z.next_out - (unsigned char *)buf; | |
400 | unuse_pack(&window); | |
401 | ||
402 | if (status == Z_STREAM_END) { | |
403 | git_inflate_end(&st->z); | |
404 | st->z_state = z_done; | |
405 | break; | |
406 | } | |
407 | if (status != Z_OK && status != Z_BUF_ERROR) { | |
408 | git_inflate_end(&st->z); | |
409 | st->z_state = z_error; | |
410 | return -1; | |
411 | } | |
412 | } | |
413 | return total_read; | |
414 | } | |
415 | ||
416 | static close_method_decl(pack_non_delta) | |
417 | { | |
418 | close_deflated_stream(st); | |
419 | return 0; | |
420 | } | |
421 | ||
422 | static struct stream_vtbl pack_non_delta_vtbl = { | |
423 | close_istream_pack_non_delta, | |
424 | read_istream_pack_non_delta, | |
425 | }; | |
426 | ||
46bf0438 JH |
427 | static open_method_decl(pack_non_delta) |
428 | { | |
7ef2d9a2 JH |
429 | struct pack_window *window; |
430 | enum object_type in_pack_type; | |
431 | ||
432 | st->u.in_pack.pack = oi->u.packed.pack; | |
433 | st->u.in_pack.pos = oi->u.packed.offset; | |
434 | window = NULL; | |
435 | ||
436 | in_pack_type = unpack_object_header(st->u.in_pack.pack, | |
437 | &window, | |
438 | &st->u.in_pack.pos, | |
439 | &st->size); | |
440 | unuse_pack(&window); | |
441 | switch (in_pack_type) { | |
442 | default: | |
443 | return -1; /* we do not do deltas for now */ | |
444 | case OBJ_COMMIT: | |
445 | case OBJ_TREE: | |
446 | case OBJ_BLOB: | |
447 | case OBJ_TAG: | |
448 | break; | |
449 | } | |
450 | st->z_state = z_unused; | |
451 | st->vtbl = &pack_non_delta_vtbl; | |
452 | return 0; | |
46bf0438 JH |
453 | } |
454 | ||
455 | ||
456 | /***************************************************************** | |
457 | * | |
458 | * In-core stream | |
459 | * | |
460 | *****************************************************************/ | |
461 | ||
462 | static close_method_decl(incore) | |
463 | { | |
464 | free(st->u.incore.buf); | |
465 | return 0; | |
466 | } | |
467 | ||
468 | static read_method_decl(incore) | |
469 | { | |
470 | size_t read_size = sz; | |
471 | size_t remainder = st->size - st->u.incore.read_ptr; | |
472 | ||
473 | if (remainder <= read_size) | |
474 | read_size = remainder; | |
475 | if (read_size) { | |
476 | memcpy(buf, st->u.incore.buf + st->u.incore.read_ptr, read_size); | |
477 | st->u.incore.read_ptr += read_size; | |
478 | } | |
479 | return read_size; | |
480 | } | |
481 | ||
482 | static struct stream_vtbl incore_vtbl = { | |
483 | close_istream_incore, | |
484 | read_istream_incore, | |
485 | }; | |
486 | ||
487 | static open_method_decl(incore) | |
488 | { | |
489 | st->u.incore.buf = read_sha1_file_extended(sha1, type, &st->size, 0); | |
490 | st->u.incore.read_ptr = 0; | |
491 | st->vtbl = &incore_vtbl; | |
492 | ||
493 | return st->u.incore.buf ? 0 : -1; | |
494 | } | |
47a02ff2 JH |
495 | |
496 | ||
497 | /**************************************************************** | |
498 | * Users of streaming interface | |
499 | ****************************************************************/ | |
500 | ||
7eda0e4f | 501 | int stream_blob_to_fd(int fd, const struct object_id *oid, struct stream_filter *filter, |
47a02ff2 JH |
502 | int can_seek) |
503 | { | |
504 | struct git_istream *st; | |
505 | enum object_type type; | |
506 | unsigned long sz; | |
507 | ssize_t kept = 0; | |
508 | int result = -1; | |
509 | ||
7eda0e4f | 510 | st = open_istream(oid->hash, &type, &sz, filter); |
9ce4ad3e JK |
511 | if (!st) { |
512 | if (filter) | |
513 | free_stream_filter(filter); | |
47a02ff2 | 514 | return result; |
9ce4ad3e | 515 | } |
47a02ff2 JH |
516 | if (type != OBJ_BLOB) |
517 | goto close_and_exit; | |
518 | for (;;) { | |
519 | char buf[1024 * 16]; | |
520 | ssize_t wrote, holeto; | |
521 | ssize_t readlen = read_istream(st, buf, sizeof(buf)); | |
522 | ||
45d4bdae JK |
523 | if (readlen < 0) |
524 | goto close_and_exit; | |
47a02ff2 JH |
525 | if (!readlen) |
526 | break; | |
527 | if (can_seek && sizeof(buf) == readlen) { | |
528 | for (holeto = 0; holeto < readlen; holeto++) | |
529 | if (buf[holeto]) | |
530 | break; | |
531 | if (readlen == holeto) { | |
532 | kept += holeto; | |
533 | continue; | |
534 | } | |
535 | } | |
536 | ||
537 | if (kept && lseek(fd, kept, SEEK_CUR) == (off_t) -1) | |
538 | goto close_and_exit; | |
539 | else | |
540 | kept = 0; | |
541 | wrote = write_in_full(fd, buf, readlen); | |
542 | ||
564bde9a | 543 | if (wrote < 0) |
47a02ff2 JH |
544 | goto close_and_exit; |
545 | } | |
546 | if (kept && (lseek(fd, kept - 1, SEEK_CUR) == (off_t) -1 || | |
7edc02f4 | 547 | xwrite(fd, "", 1) != 1)) |
47a02ff2 JH |
548 | goto close_and_exit; |
549 | result = 0; | |
550 | ||
551 | close_and_exit: | |
552 | close_istream(st); | |
553 | return result; | |
554 | } |