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Commit | Line | Data |
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46bf0438 JH |
1 | /* |
2 | * Copyright (c) 2011, Google Inc. | |
3 | */ | |
4 | #include "cache.h" | |
5 | #include "streaming.h" | |
e35454fa SB |
6 | #include "repository.h" |
7 | #include "object-store.h" | |
47f351e9 | 8 | #include "replace-object.h" |
84f80ad5 | 9 | #include "packfile.h" |
46bf0438 JH |
10 | |
11 | enum input_source { | |
12 | stream_error = -1, | |
13 | incore = 0, | |
14 | loose = 1, | |
15 | pack_non_delta = 2 | |
16 | }; | |
17 | ||
18 | typedef int (*open_istream_fn)(struct git_istream *, | |
c8123e72 | 19 | struct repository *, |
46bf0438 | 20 | struct object_info *, |
575042a0 | 21 | const struct object_id *, |
46bf0438 JH |
22 | enum object_type *); |
23 | typedef int (*close_istream_fn)(struct git_istream *); | |
24 | typedef ssize_t (*read_istream_fn)(struct git_istream *, char *, size_t); | |
25 | ||
26 | struct stream_vtbl { | |
27 | close_istream_fn close; | |
28 | read_istream_fn read; | |
29 | }; | |
30 | ||
31 | #define open_method_decl(name) \ | |
32 | int open_istream_ ##name \ | |
c8123e72 MT |
33 | (struct git_istream *st, struct repository *r, \ |
34 | struct object_info *oi, const struct object_id *oid, \ | |
46bf0438 JH |
35 | enum object_type *type) |
36 | ||
37 | #define close_method_decl(name) \ | |
38 | int close_istream_ ##name \ | |
39 | (struct git_istream *st) | |
40 | ||
41 | #define read_method_decl(name) \ | |
42 | ssize_t read_istream_ ##name \ | |
43 | (struct git_istream *st, char *buf, size_t sz) | |
44 | ||
45 | /* forward declaration */ | |
46 | static open_method_decl(incore); | |
47 | static open_method_decl(loose); | |
48 | static open_method_decl(pack_non_delta); | |
b6691092 JH |
49 | static struct git_istream *attach_stream_filter(struct git_istream *st, |
50 | struct stream_filter *filter); | |
51 | ||
46bf0438 JH |
52 | |
53 | static open_istream_fn open_istream_tbl[] = { | |
54 | open_istream_incore, | |
55 | open_istream_loose, | |
56 | open_istream_pack_non_delta, | |
57 | }; | |
58 | ||
b6691092 JH |
59 | #define FILTER_BUFFER (1024*16) |
60 | ||
61 | struct filtered_istream { | |
62 | struct git_istream *upstream; | |
63 | struct stream_filter *filter; | |
64 | char ibuf[FILTER_BUFFER]; | |
65 | char obuf[FILTER_BUFFER]; | |
66 | int i_end, i_ptr; | |
67 | int o_end, o_ptr; | |
4ae66704 | 68 | int input_finished; |
b6691092 JH |
69 | }; |
70 | ||
46bf0438 JH |
71 | struct git_istream { |
72 | const struct stream_vtbl *vtbl; | |
73 | unsigned long size; /* inflated size of full object */ | |
eb4f4076 | 74 | git_zstream z; |
7ef2d9a2 | 75 | enum { z_unused, z_used, z_done, z_error } z_state; |
46bf0438 JH |
76 | |
77 | union { | |
78 | struct { | |
79 | char *buf; /* from read_object() */ | |
80 | unsigned long read_ptr; | |
81 | } incore; | |
82 | ||
83 | struct { | |
93aa7bd5 JH |
84 | void *mapped; |
85 | unsigned long mapsize; | |
86 | char hdr[32]; | |
87 | int hdr_avail; | |
88 | int hdr_used; | |
46bf0438 JH |
89 | } loose; |
90 | ||
91 | struct { | |
7ef2d9a2 JH |
92 | struct packed_git *pack; |
93 | off_t pos; | |
46bf0438 | 94 | } in_pack; |
b6691092 JH |
95 | |
96 | struct filtered_istream filtered; | |
46bf0438 JH |
97 | } u; |
98 | }; | |
99 | ||
100 | int close_istream(struct git_istream *st) | |
101 | { | |
95dea6eb JK |
102 | int r = st->vtbl->close(st); |
103 | free(st); | |
104 | return r; | |
46bf0438 JH |
105 | } |
106 | ||
6163cd8a | 107 | ssize_t read_istream(struct git_istream *st, void *buf, size_t sz) |
46bf0438 JH |
108 | { |
109 | return st->vtbl->read(st, buf, sz); | |
110 | } | |
111 | ||
c8123e72 MT |
112 | static enum input_source istream_source(struct repository *r, |
113 | const struct object_id *oid, | |
46bf0438 JH |
114 | enum object_type *type, |
115 | struct object_info *oi) | |
116 | { | |
117 | unsigned long size; | |
118 | int status; | |
119 | ||
5b086407 | 120 | oi->typep = type; |
46bf0438 | 121 | oi->sizep = &size; |
c8123e72 | 122 | status = oid_object_info_extended(r, oid, oi, 0); |
46bf0438 JH |
123 | if (status < 0) |
124 | return stream_error; | |
46bf0438 JH |
125 | |
126 | switch (oi->whence) { | |
127 | case OI_LOOSE: | |
128 | return loose; | |
129 | case OI_PACKED: | |
754980d0 | 130 | if (!oi->u.packed.is_delta && big_file_threshold < size) |
46bf0438 JH |
131 | return pack_non_delta; |
132 | /* fallthru */ | |
133 | default: | |
134 | return incore; | |
135 | } | |
136 | } | |
137 | ||
c8123e72 MT |
138 | struct git_istream *open_istream(struct repository *r, |
139 | const struct object_id *oid, | |
46bf0438 | 140 | enum object_type *type, |
b6691092 JH |
141 | unsigned long *size, |
142 | struct stream_filter *filter) | |
46bf0438 JH |
143 | { |
144 | struct git_istream *st; | |
27b5c1a0 | 145 | struct object_info oi = OBJECT_INFO_INIT; |
c8123e72 MT |
146 | const struct object_id *real = lookup_replace_object(r, oid); |
147 | enum input_source src = istream_source(r, real, type, &oi); | |
46bf0438 JH |
148 | |
149 | if (src < 0) | |
150 | return NULL; | |
151 | ||
152 | st = xmalloc(sizeof(*st)); | |
c8123e72 MT |
153 | if (open_istream_tbl[src](st, r, &oi, real, type)) { |
154 | if (open_istream_incore(st, r, &oi, real, type)) { | |
46bf0438 JH |
155 | free(st); |
156 | return NULL; | |
157 | } | |
158 | } | |
6a907786 | 159 | if (filter) { |
b6691092 JH |
160 | /* Add "&& !is_null_stream_filter(filter)" for performance */ |
161 | struct git_istream *nst = attach_stream_filter(st, filter); | |
78368f2c | 162 | if (!nst) { |
b6691092 | 163 | close_istream(st); |
78368f2c JH |
164 | return NULL; |
165 | } | |
b6691092 JH |
166 | st = nst; |
167 | } | |
168 | ||
46bf0438 JH |
169 | *size = st->size; |
170 | return st; | |
171 | } | |
172 | ||
7ef2d9a2 JH |
173 | |
174 | /***************************************************************** | |
175 | * | |
176 | * Common helpers | |
177 | * | |
178 | *****************************************************************/ | |
179 | ||
180 | static void close_deflated_stream(struct git_istream *st) | |
181 | { | |
182 | if (st->z_state == z_used) | |
183 | git_inflate_end(&st->z); | |
184 | } | |
185 | ||
186 | ||
b6691092 JH |
187 | /***************************************************************** |
188 | * | |
189 | * Filtered stream | |
190 | * | |
191 | *****************************************************************/ | |
192 | ||
193 | static close_method_decl(filtered) | |
194 | { | |
195 | free_stream_filter(st->u.filtered.filter); | |
196 | return close_istream(st->u.filtered.upstream); | |
197 | } | |
198 | ||
199 | static read_method_decl(filtered) | |
200 | { | |
201 | struct filtered_istream *fs = &(st->u.filtered); | |
202 | size_t filled = 0; | |
203 | ||
204 | while (sz) { | |
205 | /* do we already have filtered output? */ | |
206 | if (fs->o_ptr < fs->o_end) { | |
207 | size_t to_move = fs->o_end - fs->o_ptr; | |
208 | if (sz < to_move) | |
209 | to_move = sz; | |
210 | memcpy(buf + filled, fs->obuf + fs->o_ptr, to_move); | |
211 | fs->o_ptr += to_move; | |
212 | sz -= to_move; | |
213 | filled += to_move; | |
214 | continue; | |
215 | } | |
216 | fs->o_end = fs->o_ptr = 0; | |
217 | ||
218 | /* do we have anything to feed the filter with? */ | |
219 | if (fs->i_ptr < fs->i_end) { | |
220 | size_t to_feed = fs->i_end - fs->i_ptr; | |
221 | size_t to_receive = FILTER_BUFFER; | |
222 | if (stream_filter(fs->filter, | |
223 | fs->ibuf + fs->i_ptr, &to_feed, | |
224 | fs->obuf, &to_receive)) | |
225 | return -1; | |
226 | fs->i_ptr = fs->i_end - to_feed; | |
227 | fs->o_end = FILTER_BUFFER - to_receive; | |
228 | continue; | |
229 | } | |
4ae66704 JH |
230 | |
231 | /* tell the filter to drain upon no more input */ | |
232 | if (fs->input_finished) { | |
233 | size_t to_receive = FILTER_BUFFER; | |
234 | if (stream_filter(fs->filter, | |
235 | NULL, NULL, | |
236 | fs->obuf, &to_receive)) | |
237 | return -1; | |
238 | fs->o_end = FILTER_BUFFER - to_receive; | |
239 | if (!fs->o_end) | |
240 | break; | |
241 | continue; | |
242 | } | |
b6691092 JH |
243 | fs->i_end = fs->i_ptr = 0; |
244 | ||
245 | /* refill the input from the upstream */ | |
4ae66704 JH |
246 | if (!fs->input_finished) { |
247 | fs->i_end = read_istream(fs->upstream, fs->ibuf, FILTER_BUFFER); | |
248 | if (fs->i_end < 0) | |
42e7e2a5 | 249 | return -1; |
4ae66704 JH |
250 | if (fs->i_end) |
251 | continue; | |
252 | } | |
253 | fs->input_finished = 1; | |
b6691092 JH |
254 | } |
255 | return filled; | |
256 | } | |
257 | ||
258 | static struct stream_vtbl filtered_vtbl = { | |
259 | close_istream_filtered, | |
260 | read_istream_filtered, | |
261 | }; | |
262 | ||
263 | static struct git_istream *attach_stream_filter(struct git_istream *st, | |
264 | struct stream_filter *filter) | |
265 | { | |
266 | struct git_istream *ifs = xmalloc(sizeof(*ifs)); | |
267 | struct filtered_istream *fs = &(ifs->u.filtered); | |
268 | ||
269 | ifs->vtbl = &filtered_vtbl; | |
270 | fs->upstream = st; | |
271 | fs->filter = filter; | |
272 | fs->i_end = fs->i_ptr = 0; | |
273 | fs->o_end = fs->o_ptr = 0; | |
4ae66704 | 274 | fs->input_finished = 0; |
b6691092 JH |
275 | ifs->size = -1; /* unknown */ |
276 | return ifs; | |
277 | } | |
278 | ||
46bf0438 JH |
279 | /***************************************************************** |
280 | * | |
281 | * Loose object stream | |
282 | * | |
283 | *****************************************************************/ | |
284 | ||
93aa7bd5 JH |
285 | static read_method_decl(loose) |
286 | { | |
287 | size_t total_read = 0; | |
288 | ||
289 | switch (st->z_state) { | |
290 | case z_done: | |
291 | return 0; | |
292 | case z_error: | |
293 | return -1; | |
294 | default: | |
295 | break; | |
296 | } | |
297 | ||
298 | if (st->u.loose.hdr_used < st->u.loose.hdr_avail) { | |
299 | size_t to_copy = st->u.loose.hdr_avail - st->u.loose.hdr_used; | |
300 | if (sz < to_copy) | |
301 | to_copy = sz; | |
302 | memcpy(buf, st->u.loose.hdr + st->u.loose.hdr_used, to_copy); | |
303 | st->u.loose.hdr_used += to_copy; | |
304 | total_read += to_copy; | |
305 | } | |
306 | ||
307 | while (total_read < sz) { | |
308 | int status; | |
309 | ||
310 | st->z.next_out = (unsigned char *)buf + total_read; | |
311 | st->z.avail_out = sz - total_read; | |
312 | status = git_inflate(&st->z, Z_FINISH); | |
313 | ||
314 | total_read = st->z.next_out - (unsigned char *)buf; | |
315 | ||
316 | if (status == Z_STREAM_END) { | |
317 | git_inflate_end(&st->z); | |
318 | st->z_state = z_done; | |
319 | break; | |
320 | } | |
692f0bc7 | 321 | if (status != Z_OK && (status != Z_BUF_ERROR || total_read < sz)) { |
93aa7bd5 JH |
322 | git_inflate_end(&st->z); |
323 | st->z_state = z_error; | |
324 | return -1; | |
325 | } | |
326 | } | |
327 | return total_read; | |
328 | } | |
329 | ||
330 | static close_method_decl(loose) | |
331 | { | |
332 | close_deflated_stream(st); | |
333 | munmap(st->u.loose.mapped, st->u.loose.mapsize); | |
334 | return 0; | |
335 | } | |
336 | ||
337 | static struct stream_vtbl loose_vtbl = { | |
338 | close_istream_loose, | |
339 | read_istream_loose, | |
340 | }; | |
341 | ||
46bf0438 JH |
342 | static open_method_decl(loose) |
343 | { | |
c8123e72 | 344 | st->u.loose.mapped = map_loose_object(r, oid, &st->u.loose.mapsize); |
93aa7bd5 JH |
345 | if (!st->u.loose.mapped) |
346 | return -1; | |
00a7760e JK |
347 | if ((unpack_loose_header(&st->z, |
348 | st->u.loose.mapped, | |
349 | st->u.loose.mapsize, | |
350 | st->u.loose.hdr, | |
351 | sizeof(st->u.loose.hdr)) < 0) || | |
352 | (parse_loose_header(st->u.loose.hdr, &st->size) < 0)) { | |
93aa7bd5 JH |
353 | git_inflate_end(&st->z); |
354 | munmap(st->u.loose.mapped, st->u.loose.mapsize); | |
355 | return -1; | |
356 | } | |
357 | ||
93aa7bd5 JH |
358 | st->u.loose.hdr_used = strlen(st->u.loose.hdr) + 1; |
359 | st->u.loose.hdr_avail = st->z.total_out; | |
360 | st->z_state = z_used; | |
361 | ||
362 | st->vtbl = &loose_vtbl; | |
363 | return 0; | |
46bf0438 JH |
364 | } |
365 | ||
366 | ||
367 | /***************************************************************** | |
368 | * | |
369 | * Non-delta packed object stream | |
370 | * | |
371 | *****************************************************************/ | |
372 | ||
7ef2d9a2 JH |
373 | static read_method_decl(pack_non_delta) |
374 | { | |
375 | size_t total_read = 0; | |
376 | ||
377 | switch (st->z_state) { | |
378 | case z_unused: | |
379 | memset(&st->z, 0, sizeof(st->z)); | |
380 | git_inflate_init(&st->z); | |
381 | st->z_state = z_used; | |
382 | break; | |
383 | case z_done: | |
384 | return 0; | |
385 | case z_error: | |
386 | return -1; | |
387 | case z_used: | |
388 | break; | |
389 | } | |
390 | ||
391 | while (total_read < sz) { | |
392 | int status; | |
393 | struct pack_window *window = NULL; | |
394 | unsigned char *mapped; | |
395 | ||
396 | mapped = use_pack(st->u.in_pack.pack, &window, | |
397 | st->u.in_pack.pos, &st->z.avail_in); | |
398 | ||
399 | st->z.next_out = (unsigned char *)buf + total_read; | |
400 | st->z.avail_out = sz - total_read; | |
401 | st->z.next_in = mapped; | |
402 | status = git_inflate(&st->z, Z_FINISH); | |
403 | ||
404 | st->u.in_pack.pos += st->z.next_in - mapped; | |
405 | total_read = st->z.next_out - (unsigned char *)buf; | |
406 | unuse_pack(&window); | |
407 | ||
408 | if (status == Z_STREAM_END) { | |
409 | git_inflate_end(&st->z); | |
410 | st->z_state = z_done; | |
411 | break; | |
412 | } | |
0afbe3e8 JK |
413 | |
414 | /* | |
415 | * Unlike the loose object case, we do not have to worry here | |
416 | * about running out of input bytes and spinning infinitely. If | |
417 | * we get Z_BUF_ERROR due to too few input bytes, then we'll | |
418 | * replenish them in the next use_pack() call when we loop. If | |
419 | * we truly hit the end of the pack (i.e., because it's corrupt | |
420 | * or truncated), then use_pack() catches that and will die(). | |
421 | */ | |
7ef2d9a2 JH |
422 | if (status != Z_OK && status != Z_BUF_ERROR) { |
423 | git_inflate_end(&st->z); | |
424 | st->z_state = z_error; | |
425 | return -1; | |
426 | } | |
427 | } | |
428 | return total_read; | |
429 | } | |
430 | ||
431 | static close_method_decl(pack_non_delta) | |
432 | { | |
433 | close_deflated_stream(st); | |
434 | return 0; | |
435 | } | |
436 | ||
437 | static struct stream_vtbl pack_non_delta_vtbl = { | |
438 | close_istream_pack_non_delta, | |
439 | read_istream_pack_non_delta, | |
440 | }; | |
441 | ||
46bf0438 JH |
442 | static open_method_decl(pack_non_delta) |
443 | { | |
7ef2d9a2 JH |
444 | struct pack_window *window; |
445 | enum object_type in_pack_type; | |
446 | ||
447 | st->u.in_pack.pack = oi->u.packed.pack; | |
448 | st->u.in_pack.pos = oi->u.packed.offset; | |
449 | window = NULL; | |
450 | ||
451 | in_pack_type = unpack_object_header(st->u.in_pack.pack, | |
452 | &window, | |
453 | &st->u.in_pack.pos, | |
454 | &st->size); | |
455 | unuse_pack(&window); | |
456 | switch (in_pack_type) { | |
457 | default: | |
458 | return -1; /* we do not do deltas for now */ | |
459 | case OBJ_COMMIT: | |
460 | case OBJ_TREE: | |
461 | case OBJ_BLOB: | |
462 | case OBJ_TAG: | |
463 | break; | |
464 | } | |
465 | st->z_state = z_unused; | |
466 | st->vtbl = &pack_non_delta_vtbl; | |
467 | return 0; | |
46bf0438 JH |
468 | } |
469 | ||
470 | ||
471 | /***************************************************************** | |
472 | * | |
473 | * In-core stream | |
474 | * | |
475 | *****************************************************************/ | |
476 | ||
477 | static close_method_decl(incore) | |
478 | { | |
479 | free(st->u.incore.buf); | |
480 | return 0; | |
481 | } | |
482 | ||
483 | static read_method_decl(incore) | |
484 | { | |
485 | size_t read_size = sz; | |
486 | size_t remainder = st->size - st->u.incore.read_ptr; | |
487 | ||
488 | if (remainder <= read_size) | |
489 | read_size = remainder; | |
490 | if (read_size) { | |
491 | memcpy(buf, st->u.incore.buf + st->u.incore.read_ptr, read_size); | |
492 | st->u.incore.read_ptr += read_size; | |
493 | } | |
494 | return read_size; | |
495 | } | |
496 | ||
497 | static struct stream_vtbl incore_vtbl = { | |
498 | close_istream_incore, | |
499 | read_istream_incore, | |
500 | }; | |
501 | ||
502 | static open_method_decl(incore) | |
503 | { | |
c8123e72 | 504 | st->u.incore.buf = read_object_file_extended(r, oid, type, &st->size, 0); |
46bf0438 JH |
505 | st->u.incore.read_ptr = 0; |
506 | st->vtbl = &incore_vtbl; | |
507 | ||
508 | return st->u.incore.buf ? 0 : -1; | |
509 | } | |
47a02ff2 JH |
510 | |
511 | ||
512 | /**************************************************************** | |
513 | * Users of streaming interface | |
514 | ****************************************************************/ | |
515 | ||
7eda0e4f | 516 | int stream_blob_to_fd(int fd, const struct object_id *oid, struct stream_filter *filter, |
47a02ff2 JH |
517 | int can_seek) |
518 | { | |
519 | struct git_istream *st; | |
520 | enum object_type type; | |
521 | unsigned long sz; | |
522 | ssize_t kept = 0; | |
523 | int result = -1; | |
524 | ||
c8123e72 | 525 | st = open_istream(the_repository, oid, &type, &sz, filter); |
9ce4ad3e JK |
526 | if (!st) { |
527 | if (filter) | |
528 | free_stream_filter(filter); | |
47a02ff2 | 529 | return result; |
9ce4ad3e | 530 | } |
47a02ff2 JH |
531 | if (type != OBJ_BLOB) |
532 | goto close_and_exit; | |
533 | for (;;) { | |
534 | char buf[1024 * 16]; | |
535 | ssize_t wrote, holeto; | |
536 | ssize_t readlen = read_istream(st, buf, sizeof(buf)); | |
537 | ||
45d4bdae JK |
538 | if (readlen < 0) |
539 | goto close_and_exit; | |
47a02ff2 JH |
540 | if (!readlen) |
541 | break; | |
542 | if (can_seek && sizeof(buf) == readlen) { | |
543 | for (holeto = 0; holeto < readlen; holeto++) | |
544 | if (buf[holeto]) | |
545 | break; | |
546 | if (readlen == holeto) { | |
547 | kept += holeto; | |
548 | continue; | |
549 | } | |
550 | } | |
551 | ||
552 | if (kept && lseek(fd, kept, SEEK_CUR) == (off_t) -1) | |
553 | goto close_and_exit; | |
554 | else | |
555 | kept = 0; | |
556 | wrote = write_in_full(fd, buf, readlen); | |
557 | ||
564bde9a | 558 | if (wrote < 0) |
47a02ff2 JH |
559 | goto close_and_exit; |
560 | } | |
561 | if (kept && (lseek(fd, kept - 1, SEEK_CUR) == (off_t) -1 || | |
7edc02f4 | 562 | xwrite(fd, "", 1) != 1)) |
47a02ff2 JH |
563 | goto close_and_exit; |
564 | result = 0; | |
565 | ||
566 | close_and_exit: | |
567 | close_istream(st); | |
568 | return result; | |
569 | } |