1 | /*------------------------------------------------------------------------- |
2 | * |
3 | * pg_backup_directory.c |
4 | * |
5 | * A directory format dump is a directory, which contains a "toc.dat" file |
6 | * for the TOC, and a separate file for each data entry, named "<oid>.dat". |
7 | * Large objects (BLOBs) are stored in separate files named "blob_<uid>.dat", |
8 | * and there's a plain-text TOC file for them called "blobs.toc". If |
9 | * compression is used, each data file is individually compressed and the |
10 | * ".gz" suffix is added to the filenames. The TOC files are never |
11 | * compressed by pg_dump, however they are accepted with the .gz suffix too, |
12 | * in case the user has manually compressed them with 'gzip'. |
13 | * |
14 | * NOTE: This format is identical to the files written in the tar file in |
15 | * the 'tar' format, except that we don't write the restore.sql file (TODO), |
16 | * and the tar format doesn't support compression. Please keep the formats in |
17 | * sync. |
18 | * |
19 | * |
20 | * Portions Copyright (c) 1996-2019, PostgreSQL Global Development Group |
21 | * Portions Copyright (c) 1994, Regents of the University of California |
22 | * Portions Copyright (c) 2000, Philip Warner |
23 | * |
24 | * Rights are granted to use this software in any way so long |
25 | * as this notice is not removed. |
26 | * |
27 | * The author is not responsible for loss or damages that may |
28 | * result from its use. |
29 | * |
30 | * IDENTIFICATION |
31 | * src/bin/pg_dump/pg_backup_directory.c |
32 | * |
33 | *------------------------------------------------------------------------- |
34 | */ |
35 | #include "postgres_fe.h" |
36 | |
37 | #include "compress_io.h" |
38 | #include "parallel.h" |
39 | #include "pg_backup_utils.h" |
40 | #include "common/file_utils.h" |
41 | |
42 | #include <dirent.h> |
43 | #include <sys/stat.h> |
44 | |
45 | typedef struct |
46 | { |
47 | /* |
48 | * Our archive location. This is basically what the user specified as his |
49 | * backup file but of course here it is a directory. |
50 | */ |
51 | char *directory; |
52 | |
53 | cfp *dataFH; /* currently open data file */ |
54 | |
55 | cfp *blobsTocFH; /* file handle for blobs.toc */ |
56 | ParallelState *pstate; /* for parallel backup / restore */ |
57 | } lclContext; |
58 | |
59 | typedef struct |
60 | { |
61 | char *filename; /* filename excluding the directory (basename) */ |
62 | } lclTocEntry; |
63 | |
64 | /* prototypes for private functions */ |
65 | static void _ArchiveEntry(ArchiveHandle *AH, TocEntry *te); |
66 | static void _StartData(ArchiveHandle *AH, TocEntry *te); |
67 | static void _EndData(ArchiveHandle *AH, TocEntry *te); |
68 | static void _WriteData(ArchiveHandle *AH, const void *data, size_t dLen); |
69 | static int _WriteByte(ArchiveHandle *AH, const int i); |
70 | static int _ReadByte(ArchiveHandle *); |
71 | static void _WriteBuf(ArchiveHandle *AH, const void *buf, size_t len); |
72 | static void _ReadBuf(ArchiveHandle *AH, void *buf, size_t len); |
73 | static void _CloseArchive(ArchiveHandle *AH); |
74 | static void _ReopenArchive(ArchiveHandle *AH); |
75 | static void _PrintTocData(ArchiveHandle *AH, TocEntry *te); |
76 | |
77 | static void _WriteExtraToc(ArchiveHandle *AH, TocEntry *te); |
78 | static void _ReadExtraToc(ArchiveHandle *AH, TocEntry *te); |
79 | static void _PrintExtraToc(ArchiveHandle *AH, TocEntry *te); |
80 | |
81 | static void _StartBlobs(ArchiveHandle *AH, TocEntry *te); |
82 | static void _StartBlob(ArchiveHandle *AH, TocEntry *te, Oid oid); |
83 | static void _EndBlob(ArchiveHandle *AH, TocEntry *te, Oid oid); |
84 | static void _EndBlobs(ArchiveHandle *AH, TocEntry *te); |
85 | static void _LoadBlobs(ArchiveHandle *AH); |
86 | |
87 | static void _PrepParallelRestore(ArchiveHandle *AH); |
88 | static void _Clone(ArchiveHandle *AH); |
89 | static void _DeClone(ArchiveHandle *AH); |
90 | |
91 | static int _WorkerJobRestoreDirectory(ArchiveHandle *AH, TocEntry *te); |
92 | static int _WorkerJobDumpDirectory(ArchiveHandle *AH, TocEntry *te); |
93 | |
94 | static void setFilePath(ArchiveHandle *AH, char *buf, |
95 | const char *relativeFilename); |
96 | |
97 | /* |
98 | * Init routine required by ALL formats. This is a global routine |
99 | * and should be declared in pg_backup_archiver.h |
100 | * |
101 | * Its task is to create any extra archive context (using AH->formatData), |
102 | * and to initialize the supported function pointers. |
103 | * |
104 | * It should also prepare whatever its input source is for reading/writing, |
105 | * and in the case of a read mode connection, it should load the Header & TOC. |
106 | */ |
107 | void |
108 | InitArchiveFmt_Directory(ArchiveHandle *AH) |
109 | { |
110 | lclContext *ctx; |
111 | |
112 | /* Assuming static functions, this can be copied for each format. */ |
113 | AH->ArchiveEntryPtr = _ArchiveEntry; |
114 | AH->StartDataPtr = _StartData; |
115 | AH->WriteDataPtr = _WriteData; |
116 | AH->EndDataPtr = _EndData; |
117 | AH->WriteBytePtr = _WriteByte; |
118 | AH->ReadBytePtr = _ReadByte; |
119 | AH->WriteBufPtr = _WriteBuf; |
120 | AH->ReadBufPtr = _ReadBuf; |
121 | AH->ClosePtr = _CloseArchive; |
122 | AH->ReopenPtr = _ReopenArchive; |
123 | AH->PrintTocDataPtr = _PrintTocData; |
124 | AH->ReadExtraTocPtr = _ReadExtraToc; |
125 | AH->WriteExtraTocPtr = _WriteExtraToc; |
126 | AH->PrintExtraTocPtr = _PrintExtraToc; |
127 | |
128 | AH->StartBlobsPtr = _StartBlobs; |
129 | AH->StartBlobPtr = _StartBlob; |
130 | AH->EndBlobPtr = _EndBlob; |
131 | AH->EndBlobsPtr = _EndBlobs; |
132 | |
133 | AH->PrepParallelRestorePtr = _PrepParallelRestore; |
134 | AH->ClonePtr = _Clone; |
135 | AH->DeClonePtr = _DeClone; |
136 | |
137 | AH->WorkerJobRestorePtr = _WorkerJobRestoreDirectory; |
138 | AH->WorkerJobDumpPtr = _WorkerJobDumpDirectory; |
139 | |
140 | /* Set up our private context */ |
141 | ctx = (lclContext *) pg_malloc0(sizeof(lclContext)); |
142 | AH->formatData = (void *) ctx; |
143 | |
144 | ctx->dataFH = NULL; |
145 | ctx->blobsTocFH = NULL; |
146 | |
147 | /* Initialize LO buffering */ |
148 | AH->lo_buf_size = LOBBUFSIZE; |
149 | AH->lo_buf = (void *) pg_malloc(LOBBUFSIZE); |
150 | |
151 | /* |
152 | * Now open the TOC file |
153 | */ |
154 | |
155 | if (!AH->fSpec || strcmp(AH->fSpec, "" ) == 0) |
156 | fatal("no output directory specified" ); |
157 | |
158 | ctx->directory = AH->fSpec; |
159 | |
160 | if (AH->mode == archModeWrite) |
161 | { |
162 | struct stat st; |
163 | bool is_empty = false; |
164 | |
165 | /* we accept an empty existing directory */ |
166 | if (stat(ctx->directory, &st) == 0 && S_ISDIR(st.st_mode)) |
167 | { |
168 | DIR *dir = opendir(ctx->directory); |
169 | |
170 | if (dir) |
171 | { |
172 | struct dirent *d; |
173 | |
174 | is_empty = true; |
175 | while (errno = 0, (d = readdir(dir))) |
176 | { |
177 | if (strcmp(d->d_name, "." ) != 0 && strcmp(d->d_name, ".." ) != 0) |
178 | { |
179 | is_empty = false; |
180 | break; |
181 | } |
182 | } |
183 | |
184 | if (errno) |
185 | fatal("could not read directory \"%s\": %m" , |
186 | ctx->directory); |
187 | |
188 | if (closedir(dir)) |
189 | fatal("could not close directory \"%s\": %m" , |
190 | ctx->directory); |
191 | } |
192 | } |
193 | |
194 | if (!is_empty && mkdir(ctx->directory, 0700) < 0) |
195 | fatal("could not create directory \"%s\": %m" , |
196 | ctx->directory); |
197 | } |
198 | else |
199 | { /* Read Mode */ |
200 | char fname[MAXPGPATH]; |
201 | cfp *tocFH; |
202 | |
203 | setFilePath(AH, fname, "toc.dat" ); |
204 | |
205 | tocFH = cfopen_read(fname, PG_BINARY_R); |
206 | if (tocFH == NULL) |
207 | fatal("could not open input file \"%s\": %m" , fname); |
208 | |
209 | ctx->dataFH = tocFH; |
210 | |
211 | /* |
212 | * The TOC of a directory format dump shares the format code of the |
213 | * tar format. |
214 | */ |
215 | AH->format = archTar; |
216 | ReadHead(AH); |
217 | AH->format = archDirectory; |
218 | ReadToc(AH); |
219 | |
220 | /* Nothing else in the file, so close it again... */ |
221 | if (cfclose(tocFH) != 0) |
222 | fatal("could not close TOC file: %m" ); |
223 | ctx->dataFH = NULL; |
224 | } |
225 | } |
226 | |
227 | /* |
228 | * Called by the Archiver when the dumper creates a new TOC entry. |
229 | * |
230 | * We determine the filename for this entry. |
231 | */ |
232 | static void |
233 | _ArchiveEntry(ArchiveHandle *AH, TocEntry *te) |
234 | { |
235 | lclTocEntry *tctx; |
236 | char fn[MAXPGPATH]; |
237 | |
238 | tctx = (lclTocEntry *) pg_malloc0(sizeof(lclTocEntry)); |
239 | if (strcmp(te->desc, "BLOBS" ) == 0) |
240 | tctx->filename = pg_strdup("blobs.toc" ); |
241 | else if (te->dataDumper) |
242 | { |
243 | snprintf(fn, MAXPGPATH, "%d.dat" , te->dumpId); |
244 | tctx->filename = pg_strdup(fn); |
245 | } |
246 | else |
247 | tctx->filename = NULL; |
248 | |
249 | te->formatData = (void *) tctx; |
250 | } |
251 | |
252 | /* |
253 | * Called by the Archiver to save any extra format-related TOC entry |
254 | * data. |
255 | * |
256 | * Use the Archiver routines to write data - they are non-endian, and |
257 | * maintain other important file information. |
258 | */ |
259 | static void |
260 | (ArchiveHandle *AH, TocEntry *te) |
261 | { |
262 | lclTocEntry *tctx = (lclTocEntry *) te->formatData; |
263 | |
264 | /* |
265 | * A dumpable object has set tctx->filename, any other object has not. |
266 | * (see _ArchiveEntry). |
267 | */ |
268 | if (tctx->filename) |
269 | WriteStr(AH, tctx->filename); |
270 | else |
271 | WriteStr(AH, "" ); |
272 | } |
273 | |
274 | /* |
275 | * Called by the Archiver to read any extra format-related TOC data. |
276 | * |
277 | * Needs to match the order defined in _WriteExtraToc, and should also |
278 | * use the Archiver input routines. |
279 | */ |
280 | static void |
281 | (ArchiveHandle *AH, TocEntry *te) |
282 | { |
283 | lclTocEntry *tctx = (lclTocEntry *) te->formatData; |
284 | |
285 | if (tctx == NULL) |
286 | { |
287 | tctx = (lclTocEntry *) pg_malloc0(sizeof(lclTocEntry)); |
288 | te->formatData = (void *) tctx; |
289 | } |
290 | |
291 | tctx->filename = ReadStr(AH); |
292 | if (strlen(tctx->filename) == 0) |
293 | { |
294 | free(tctx->filename); |
295 | tctx->filename = NULL; |
296 | } |
297 | } |
298 | |
299 | /* |
300 | * Called by the Archiver when restoring an archive to output a comment |
301 | * that includes useful information about the TOC entry. |
302 | */ |
303 | static void |
304 | (ArchiveHandle *AH, TocEntry *te) |
305 | { |
306 | lclTocEntry *tctx = (lclTocEntry *) te->formatData; |
307 | |
308 | if (AH->public.verbose && tctx->filename) |
309 | ahprintf(AH, "-- File: %s\n" , tctx->filename); |
310 | } |
311 | |
312 | /* |
313 | * Called by the archiver when saving TABLE DATA (not schema). This routine |
314 | * should save whatever format-specific information is needed to read |
315 | * the archive back. |
316 | * |
317 | * It is called just prior to the dumper's 'DataDumper' routine being called. |
318 | * |
319 | * We create the data file for writing. |
320 | */ |
321 | static void |
322 | _StartData(ArchiveHandle *AH, TocEntry *te) |
323 | { |
324 | lclTocEntry *tctx = (lclTocEntry *) te->formatData; |
325 | lclContext *ctx = (lclContext *) AH->formatData; |
326 | char fname[MAXPGPATH]; |
327 | |
328 | setFilePath(AH, fname, tctx->filename); |
329 | |
330 | ctx->dataFH = cfopen_write(fname, PG_BINARY_W, AH->compression); |
331 | if (ctx->dataFH == NULL) |
332 | fatal("could not open output file \"%s\": %m" , fname); |
333 | } |
334 | |
335 | /* |
336 | * Called by archiver when dumper calls WriteData. This routine is |
337 | * called for both BLOB and TABLE data; it is the responsibility of |
338 | * the format to manage each kind of data using StartBlob/StartData. |
339 | * |
340 | * It should only be called from within a DataDumper routine. |
341 | * |
342 | * We write the data to the open data file. |
343 | */ |
344 | static void |
345 | _WriteData(ArchiveHandle *AH, const void *data, size_t dLen) |
346 | { |
347 | lclContext *ctx = (lclContext *) AH->formatData; |
348 | |
349 | if (dLen > 0 && cfwrite(data, dLen, ctx->dataFH) != dLen) |
350 | fatal("could not write to output file: %s" , |
351 | get_cfp_error(ctx->dataFH)); |
352 | |
353 | |
354 | return; |
355 | } |
356 | |
357 | /* |
358 | * Called by the archiver when a dumper's 'DataDumper' routine has |
359 | * finished. |
360 | * |
361 | * We close the data file. |
362 | */ |
363 | static void |
364 | _EndData(ArchiveHandle *AH, TocEntry *te) |
365 | { |
366 | lclContext *ctx = (lclContext *) AH->formatData; |
367 | |
368 | /* Close the file */ |
369 | cfclose(ctx->dataFH); |
370 | |
371 | ctx->dataFH = NULL; |
372 | } |
373 | |
374 | /* |
375 | * Print data for a given file (can be a BLOB as well) |
376 | */ |
377 | static void |
378 | _PrintFileData(ArchiveHandle *AH, char *filename) |
379 | { |
380 | size_t cnt; |
381 | char *buf; |
382 | size_t buflen; |
383 | cfp *cfp; |
384 | |
385 | if (!filename) |
386 | return; |
387 | |
388 | cfp = cfopen_read(filename, PG_BINARY_R); |
389 | |
390 | if (!cfp) |
391 | fatal("could not open input file \"%s\": %m" , filename); |
392 | |
393 | buf = pg_malloc(ZLIB_OUT_SIZE); |
394 | buflen = ZLIB_OUT_SIZE; |
395 | |
396 | while ((cnt = cfread(buf, buflen, cfp))) |
397 | { |
398 | ahwrite(buf, 1, cnt, AH); |
399 | } |
400 | |
401 | free(buf); |
402 | if (cfclose(cfp) !=0) |
403 | fatal("could not close data file: %m" ); |
404 | } |
405 | |
406 | /* |
407 | * Print data for a given TOC entry |
408 | */ |
409 | static void |
410 | _PrintTocData(ArchiveHandle *AH, TocEntry *te) |
411 | { |
412 | lclTocEntry *tctx = (lclTocEntry *) te->formatData; |
413 | |
414 | if (!tctx->filename) |
415 | return; |
416 | |
417 | if (strcmp(te->desc, "BLOBS" ) == 0) |
418 | _LoadBlobs(AH); |
419 | else |
420 | { |
421 | char fname[MAXPGPATH]; |
422 | |
423 | setFilePath(AH, fname, tctx->filename); |
424 | _PrintFileData(AH, fname); |
425 | } |
426 | } |
427 | |
428 | static void |
429 | _LoadBlobs(ArchiveHandle *AH) |
430 | { |
431 | Oid oid; |
432 | lclContext *ctx = (lclContext *) AH->formatData; |
433 | char fname[MAXPGPATH]; |
434 | char line[MAXPGPATH]; |
435 | |
436 | StartRestoreBlobs(AH); |
437 | |
438 | setFilePath(AH, fname, "blobs.toc" ); |
439 | |
440 | ctx->blobsTocFH = cfopen_read(fname, PG_BINARY_R); |
441 | |
442 | if (ctx->blobsTocFH == NULL) |
443 | fatal("could not open large object TOC file \"%s\" for input: %m" , |
444 | fname); |
445 | |
446 | /* Read the blobs TOC file line-by-line, and process each blob */ |
447 | while ((cfgets(ctx->blobsTocFH, line, MAXPGPATH)) != NULL) |
448 | { |
449 | char fname[MAXPGPATH]; |
450 | char path[MAXPGPATH]; |
451 | |
452 | /* Can't overflow because line and fname are the same length. */ |
453 | if (sscanf(line, "%u %s\n" , &oid, fname) != 2) |
454 | fatal("invalid line in large object TOC file \"%s\": \"%s\"" , |
455 | fname, line); |
456 | |
457 | StartRestoreBlob(AH, oid, AH->public.ropt->dropSchema); |
458 | snprintf(path, MAXPGPATH, "%s/%s" , ctx->directory, fname); |
459 | _PrintFileData(AH, path); |
460 | EndRestoreBlob(AH, oid); |
461 | } |
462 | if (!cfeof(ctx->blobsTocFH)) |
463 | fatal("error reading large object TOC file \"%s\"" , |
464 | fname); |
465 | |
466 | if (cfclose(ctx->blobsTocFH) != 0) |
467 | fatal("could not close large object TOC file \"%s\": %m" , |
468 | fname); |
469 | |
470 | ctx->blobsTocFH = NULL; |
471 | |
472 | EndRestoreBlobs(AH); |
473 | } |
474 | |
475 | |
476 | /* |
477 | * Write a byte of data to the archive. |
478 | * Called by the archiver to do integer & byte output to the archive. |
479 | * These routines are only used to read & write the headers & TOC. |
480 | */ |
481 | static int |
482 | _WriteByte(ArchiveHandle *AH, const int i) |
483 | { |
484 | unsigned char c = (unsigned char) i; |
485 | lclContext *ctx = (lclContext *) AH->formatData; |
486 | |
487 | if (cfwrite(&c, 1, ctx->dataFH) != 1) |
488 | fatal("could not write to output file: %s" , |
489 | get_cfp_error(ctx->dataFH)); |
490 | |
491 | return 1; |
492 | } |
493 | |
494 | /* |
495 | * Read a byte of data from the archive. |
496 | * Called by the archiver to read bytes & integers from the archive. |
497 | * These routines are only used to read & write headers & TOC. |
498 | * EOF should be treated as a fatal error. |
499 | */ |
500 | static int |
501 | _ReadByte(ArchiveHandle *AH) |
502 | { |
503 | lclContext *ctx = (lclContext *) AH->formatData; |
504 | |
505 | return cfgetc(ctx->dataFH); |
506 | } |
507 | |
508 | /* |
509 | * Write a buffer of data to the archive. |
510 | * Called by the archiver to write a block of bytes to the TOC or a data file. |
511 | */ |
512 | static void |
513 | _WriteBuf(ArchiveHandle *AH, const void *buf, size_t len) |
514 | { |
515 | lclContext *ctx = (lclContext *) AH->formatData; |
516 | |
517 | if (cfwrite(buf, len, ctx->dataFH) != len) |
518 | fatal("could not write to output file: %s" , |
519 | get_cfp_error(ctx->dataFH)); |
520 | |
521 | return; |
522 | } |
523 | |
524 | /* |
525 | * Read a block of bytes from the archive. |
526 | * |
527 | * Called by the archiver to read a block of bytes from the archive |
528 | */ |
529 | static void |
530 | _ReadBuf(ArchiveHandle *AH, void *buf, size_t len) |
531 | { |
532 | lclContext *ctx = (lclContext *) AH->formatData; |
533 | |
534 | /* |
535 | * If there was an I/O error, we already exited in cfread(), so here we |
536 | * exit on short reads. |
537 | */ |
538 | if (cfread(buf, len, ctx->dataFH) != len) |
539 | fatal("could not read from input file: end of file" ); |
540 | |
541 | return; |
542 | } |
543 | |
544 | /* |
545 | * Close the archive. |
546 | * |
547 | * When writing the archive, this is the routine that actually starts |
548 | * the process of saving it to files. No data should be written prior |
549 | * to this point, since the user could sort the TOC after creating it. |
550 | * |
551 | * If an archive is to be written, this routine must call: |
552 | * WriteHead to save the archive header |
553 | * WriteToc to save the TOC entries |
554 | * WriteDataChunks to save all DATA & BLOBs. |
555 | */ |
556 | static void |
557 | _CloseArchive(ArchiveHandle *AH) |
558 | { |
559 | lclContext *ctx = (lclContext *) AH->formatData; |
560 | |
561 | if (AH->mode == archModeWrite) |
562 | { |
563 | cfp *tocFH; |
564 | char fname[MAXPGPATH]; |
565 | |
566 | setFilePath(AH, fname, "toc.dat" ); |
567 | |
568 | /* this will actually fork the processes for a parallel backup */ |
569 | ctx->pstate = ParallelBackupStart(AH); |
570 | |
571 | /* The TOC is always created uncompressed */ |
572 | tocFH = cfopen_write(fname, PG_BINARY_W, 0); |
573 | if (tocFH == NULL) |
574 | fatal("could not open output file \"%s\": %m" , fname); |
575 | ctx->dataFH = tocFH; |
576 | |
577 | /* |
578 | * Write 'tar' in the format field of the toc.dat file. The directory |
579 | * is compatible with 'tar', so there's no point having a different |
580 | * format code for it. |
581 | */ |
582 | AH->format = archTar; |
583 | WriteHead(AH); |
584 | AH->format = archDirectory; |
585 | WriteToc(AH); |
586 | if (cfclose(tocFH) != 0) |
587 | fatal("could not close TOC file: %m" ); |
588 | WriteDataChunks(AH, ctx->pstate); |
589 | |
590 | ParallelBackupEnd(AH, ctx->pstate); |
591 | |
592 | /* |
593 | * In directory mode, there is no need to sync all the entries |
594 | * individually. Just recurse once through all the files generated. |
595 | */ |
596 | if (AH->dosync) |
597 | fsync_dir_recurse(ctx->directory); |
598 | } |
599 | AH->FH = NULL; |
600 | } |
601 | |
602 | /* |
603 | * Reopen the archive's file handle. |
604 | */ |
605 | static void |
606 | _ReopenArchive(ArchiveHandle *AH) |
607 | { |
608 | /* |
609 | * Our TOC is in memory, our data files are opened by each child anyway as |
610 | * they are separate. We support reopening the archive by just doing |
611 | * nothing. |
612 | */ |
613 | } |
614 | |
615 | /* |
616 | * BLOB support |
617 | */ |
618 | |
619 | /* |
620 | * Called by the archiver when starting to save all BLOB DATA (not schema). |
621 | * It is called just prior to the dumper's DataDumper routine. |
622 | * |
623 | * We open the large object TOC file here, so that we can append a line to |
624 | * it for each blob. |
625 | */ |
626 | static void |
627 | _StartBlobs(ArchiveHandle *AH, TocEntry *te) |
628 | { |
629 | lclContext *ctx = (lclContext *) AH->formatData; |
630 | char fname[MAXPGPATH]; |
631 | |
632 | setFilePath(AH, fname, "blobs.toc" ); |
633 | |
634 | /* The blob TOC file is never compressed */ |
635 | ctx->blobsTocFH = cfopen_write(fname, "ab" , 0); |
636 | if (ctx->blobsTocFH == NULL) |
637 | fatal("could not open output file \"%s\": %m" , fname); |
638 | } |
639 | |
640 | /* |
641 | * Called by the archiver when we're about to start dumping a blob. |
642 | * |
643 | * We create a file to write the blob to. |
644 | */ |
645 | static void |
646 | _StartBlob(ArchiveHandle *AH, TocEntry *te, Oid oid) |
647 | { |
648 | lclContext *ctx = (lclContext *) AH->formatData; |
649 | char fname[MAXPGPATH]; |
650 | |
651 | snprintf(fname, MAXPGPATH, "%s/blob_%u.dat" , ctx->directory, oid); |
652 | |
653 | ctx->dataFH = cfopen_write(fname, PG_BINARY_W, AH->compression); |
654 | |
655 | if (ctx->dataFH == NULL) |
656 | fatal("could not open output file \"%s\": %m" , fname); |
657 | } |
658 | |
659 | /* |
660 | * Called by the archiver when the dumper is finished writing a blob. |
661 | * |
662 | * We close the blob file and write an entry to the blob TOC file for it. |
663 | */ |
664 | static void |
665 | _EndBlob(ArchiveHandle *AH, TocEntry *te, Oid oid) |
666 | { |
667 | lclContext *ctx = (lclContext *) AH->formatData; |
668 | char buf[50]; |
669 | int len; |
670 | |
671 | /* Close the BLOB data file itself */ |
672 | cfclose(ctx->dataFH); |
673 | ctx->dataFH = NULL; |
674 | |
675 | /* register the blob in blobs.toc */ |
676 | len = snprintf(buf, sizeof(buf), "%u blob_%u.dat\n" , oid, oid); |
677 | if (cfwrite(buf, len, ctx->blobsTocFH) != len) |
678 | fatal("could not write to blobs TOC file" ); |
679 | } |
680 | |
681 | /* |
682 | * Called by the archiver when finishing saving all BLOB DATA. |
683 | * |
684 | * We close the blobs TOC file. |
685 | */ |
686 | static void |
687 | _EndBlobs(ArchiveHandle *AH, TocEntry *te) |
688 | { |
689 | lclContext *ctx = (lclContext *) AH->formatData; |
690 | |
691 | cfclose(ctx->blobsTocFH); |
692 | ctx->blobsTocFH = NULL; |
693 | } |
694 | |
695 | /* |
696 | * Gets a relative file name and prepends the output directory, writing the |
697 | * result to buf. The caller needs to make sure that buf is MAXPGPATH bytes |
698 | * big. Can't use a static char[MAXPGPATH] inside the function because we run |
699 | * multithreaded on Windows. |
700 | */ |
701 | static void |
702 | setFilePath(ArchiveHandle *AH, char *buf, const char *relativeFilename) |
703 | { |
704 | lclContext *ctx = (lclContext *) AH->formatData; |
705 | char *dname; |
706 | |
707 | dname = ctx->directory; |
708 | |
709 | if (strlen(dname) + 1 + strlen(relativeFilename) + 1 > MAXPGPATH) |
710 | fatal("file name too long: \"%s\"" , dname); |
711 | |
712 | strcpy(buf, dname); |
713 | strcat(buf, "/" ); |
714 | strcat(buf, relativeFilename); |
715 | } |
716 | |
717 | /* |
718 | * Prepare for parallel restore. |
719 | * |
720 | * The main thing that needs to happen here is to fill in TABLE DATA and BLOBS |
721 | * TOC entries' dataLength fields with appropriate values to guide the |
722 | * ordering of restore jobs. The source of said data is format-dependent, |
723 | * as is the exact meaning of the values. |
724 | * |
725 | * A format module might also choose to do other setup here. |
726 | */ |
727 | static void |
728 | _PrepParallelRestore(ArchiveHandle *AH) |
729 | { |
730 | TocEntry *te; |
731 | |
732 | for (te = AH->toc->next; te != AH->toc; te = te->next) |
733 | { |
734 | lclTocEntry *tctx = (lclTocEntry *) te->formatData; |
735 | char fname[MAXPGPATH]; |
736 | struct stat st; |
737 | |
738 | /* |
739 | * A dumpable object has set tctx->filename, any other object has not. |
740 | * (see _ArchiveEntry). |
741 | */ |
742 | if (tctx->filename == NULL) |
743 | continue; |
744 | |
745 | /* We may ignore items not due to be restored */ |
746 | if ((te->reqs & REQ_DATA) == 0) |
747 | continue; |
748 | |
749 | /* |
750 | * Stat the file and, if successful, put its size in dataLength. When |
751 | * using compression, the physical file size might not be a very good |
752 | * guide to the amount of work involved in restoring the file, but we |
753 | * only need an approximate indicator of that. |
754 | */ |
755 | setFilePath(AH, fname, tctx->filename); |
756 | |
757 | if (stat(fname, &st) == 0) |
758 | te->dataLength = st.st_size; |
759 | else |
760 | { |
761 | /* It might be compressed */ |
762 | strlcat(fname, ".gz" , sizeof(fname)); |
763 | if (stat(fname, &st) == 0) |
764 | te->dataLength = st.st_size; |
765 | } |
766 | |
767 | /* |
768 | * If this is the BLOBS entry, what we stat'd was blobs.toc, which |
769 | * most likely is a lot smaller than the actual blob data. We don't |
770 | * have a cheap way to estimate how much smaller, but fortunately it |
771 | * doesn't matter too much as long as we get the blobs processed |
772 | * reasonably early. Arbitrarily scale up by a factor of 1K. |
773 | */ |
774 | if (strcmp(te->desc, "BLOBS" ) == 0) |
775 | te->dataLength *= 1024; |
776 | } |
777 | } |
778 | |
779 | /* |
780 | * Clone format-specific fields during parallel restoration. |
781 | */ |
782 | static void |
783 | _Clone(ArchiveHandle *AH) |
784 | { |
785 | lclContext *ctx = (lclContext *) AH->formatData; |
786 | |
787 | AH->formatData = (lclContext *) pg_malloc(sizeof(lclContext)); |
788 | memcpy(AH->formatData, ctx, sizeof(lclContext)); |
789 | ctx = (lclContext *) AH->formatData; |
790 | |
791 | /* |
792 | * Note: we do not make a local lo_buf because we expect at most one BLOBS |
793 | * entry per archive, so no parallelism is possible. Likewise, |
794 | * TOC-entry-local state isn't an issue because any one TOC entry is |
795 | * touched by just one worker child. |
796 | */ |
797 | |
798 | /* |
799 | * We also don't copy the ParallelState pointer (pstate), only the master |
800 | * process ever writes to it. |
801 | */ |
802 | } |
803 | |
804 | static void |
805 | _DeClone(ArchiveHandle *AH) |
806 | { |
807 | lclContext *ctx = (lclContext *) AH->formatData; |
808 | |
809 | free(ctx); |
810 | } |
811 | |
812 | /* |
813 | * This function is executed in the child of a parallel backup for a |
814 | * directory-format archive and dumps the actual data for one TOC entry. |
815 | */ |
816 | static int |
817 | _WorkerJobDumpDirectory(ArchiveHandle *AH, TocEntry *te) |
818 | { |
819 | /* |
820 | * This function returns void. We either fail and die horribly or |
821 | * succeed... A failure will be detected by the parent when the child dies |
822 | * unexpectedly. |
823 | */ |
824 | WriteDataChunksForTocEntry(AH, te); |
825 | |
826 | return 0; |
827 | } |
828 | |
829 | /* |
830 | * This function is executed in the child of a parallel restore from a |
831 | * directory-format archive and restores the actual data for one TOC entry. |
832 | */ |
833 | static int |
834 | _WorkerJobRestoreDirectory(ArchiveHandle *AH, TocEntry *te) |
835 | { |
836 | return parallel_restore(AH, te); |
837 | } |
838 | |