PostgreSQL Source Code git master
file_ops.c File Reference
#include "postgres_fe.h"
#include <sys/stat.h>
#include <dirent.h>
#include <fcntl.h>
#include <unistd.h>
#include "common/file_perm.h"
#include "common/file_utils.h"
#include "file_ops.h"
#include "filemap.h"
#include "pg_rewind.h"
Include dependency graph for file_ops.c:

Go to the source code of this file.

Functions

static void create_target_dir (const char *path)
 
static void remove_target_dir (const char *path)
 
static void create_target_symlink (const char *path, const char *link)
 
static void remove_target_symlink (const char *path)
 
static void recurse_dir (const char *datadir, const char *parentpath, process_file_callback_t callback)
 
void open_target_file (const char *path, bool trunc)
 
void close_target_file (void)
 
void write_target_range (char *buf, off_t begin, size_t size)
 
void remove_target (file_entry_t *entry)
 
void create_target (file_entry_t *entry)
 
void remove_target_file (const char *path, bool missing_ok)
 
void truncate_target_file (const char *path, off_t newsize)
 
void sync_target_dir (void)
 
char * slurpFile (const char *datadir, const char *path, size_t *filesize)
 
void traverse_datadir (const char *datadir, process_file_callback_t callback)
 

Variables

static int dstfd = -1
 
static char dstpath [MAXPGPATH] = ""
 

Function Documentation

◆ close_target_file()

void close_target_file ( void  )

Definition at line 75 of file file_ops.c.

76{
77 if (dstfd == -1)
78 return;
79
80 if (close(dstfd) != 0)
81 pg_fatal("could not close target file \"%s\": %m",
82 dstpath);
83
84 dstfd = -1;
85}
static char dstpath[MAXPGPATH]
Definition: file_ops.c:32
static int dstfd
Definition: file_ops.c:31
#define close(a)
Definition: win32.h:12
#define pg_fatal(...)

References close, dstfd, dstpath, and pg_fatal.

Referenced by createBackupLabel(), open_target_file(), and perform_rewind().

◆ create_target()

void create_target ( file_entry_t entry)

Definition at line 156 of file file_ops.c.

157{
159 Assert(!entry->target_exists);
160
161 switch (entry->source_type)
162 {
164 create_target_dir(entry->path);
165 break;
166
169 break;
170
172 /* can't happen. Regular files are created with open_target_file. */
173 pg_fatal("invalid action (CREATE) for regular file");
174 break;
175
177 pg_fatal("undefined file type for \"%s\"", entry->path);
178 break;
179 }
180}
#define Assert(condition)
Definition: c.h:815
static void create_target_symlink(const char *path, const char *link)
Definition: file_ops.c:257
static void create_target_dir(const char *path)
Definition: file_ops.c:229
@ FILE_ACTION_CREATE
Definition: filemap.h:20
@ FILE_TYPE_UNDEFINED
Definition: filemap.h:32
@ FILE_TYPE_REGULAR
Definition: filemap.h:34
@ FILE_TYPE_SYMLINK
Definition: filemap.h:36
@ FILE_TYPE_DIRECTORY
Definition: filemap.h:35
const char * path
Definition: filemap.h:53
bool target_exists
Definition: filemap.h:59
char * source_link_target
Definition: filemap.h:76
file_type_t source_type
Definition: filemap.h:74
file_action_t action
Definition: filemap.h:81

References file_entry_t::action, Assert, create_target_dir(), create_target_symlink(), FILE_ACTION_CREATE, FILE_TYPE_DIRECTORY, FILE_TYPE_REGULAR, FILE_TYPE_SYMLINK, FILE_TYPE_UNDEFINED, file_entry_t::path, pg_fatal, file_entry_t::source_link_target, file_entry_t::source_type, and file_entry_t::target_exists.

Referenced by perform_rewind().

◆ create_target_dir()

static void create_target_dir ( const char *  path)
static

Definition at line 229 of file file_ops.c.

230{
231 char dstpath[MAXPGPATH];
232
233 if (dry_run)
234 return;
235
236 snprintf(dstpath, sizeof(dstpath), "%s/%s", datadir_target, path);
238 pg_fatal("could not create directory \"%s\": %m",
239 dstpath);
240}
int pg_dir_create_mode
Definition: file_perm.c:18
#define MAXPGPATH
static bool dry_run
char * datadir_target
Definition: pg_rewind.c:67
#define snprintf
Definition: port.h:239
#define mkdir(a, b)
Definition: win32_port.h:80

References datadir_target, dry_run, dstpath, MAXPGPATH, mkdir, pg_dir_create_mode, pg_fatal, and snprintf.

Referenced by create_target().

◆ create_target_symlink()

static void create_target_symlink ( const char *  path,
const char *  link 
)
static

Definition at line 257 of file file_ops.c.

258{
259 char dstpath[MAXPGPATH];
260
261 if (dry_run)
262 return;
263
264 snprintf(dstpath, sizeof(dstpath), "%s/%s", datadir_target, path);
265 if (symlink(link, dstpath) != 0)
266 pg_fatal("could not create symbolic link at \"%s\": %m",
267 dstpath);
268}
#define symlink(oldpath, newpath)
Definition: win32_port.h:225

References datadir_target, dry_run, dstpath, MAXPGPATH, pg_fatal, snprintf, and symlink.

Referenced by create_target().

◆ open_target_file()

void open_target_file ( const char *  path,
bool  trunc 
)

Definition at line 47 of file file_ops.c.

48{
49 int mode;
50
51 if (dry_run)
52 return;
53
54 if (dstfd != -1 && !trunc &&
55 strcmp(path, &dstpath[strlen(datadir_target) + 1]) == 0)
56 return; /* already open */
57
59
60 snprintf(dstpath, sizeof(dstpath), "%s/%s", datadir_target, path);
61
62 mode = O_WRONLY | O_CREAT | PG_BINARY;
63 if (trunc)
64 mode |= O_TRUNC;
66 if (dstfd < 0)
67 pg_fatal("could not open target file \"%s\": %m",
68 dstpath);
69}
#define PG_BINARY
Definition: c.h:1230
void close_target_file(void)
Definition: file_ops.c:75
int pg_file_create_mode
Definition: file_perm.c:19
static PgChecksumMode mode
Definition: pg_checksums.c:55

References close_target_file(), datadir_target, dry_run, dstfd, dstpath, mode, PG_BINARY, pg_fatal, pg_file_create_mode, and snprintf.

Referenced by createBackupLabel(), libpq_queue_fetch_file(), local_queue_fetch_file(), local_queue_fetch_range(), and process_queued_fetch_requests().

◆ recurse_dir()

static void recurse_dir ( const char *  datadir,
const char *  parentpath,
process_file_callback_t  callback 
)
static

Definition at line 374 of file file_ops.c.

376{
377 DIR *xldir;
378 struct dirent *xlde;
379 char fullparentpath[MAXPGPATH];
380
381 if (parentpath)
382 snprintf(fullparentpath, MAXPGPATH, "%s/%s", datadir, parentpath);
383 else
384 snprintf(fullparentpath, MAXPGPATH, "%s", datadir);
385
386 xldir = opendir(fullparentpath);
387 if (xldir == NULL)
388 pg_fatal("could not open directory \"%s\": %m",
389 fullparentpath);
390
391 while (errno = 0, (xlde = readdir(xldir)) != NULL)
392 {
393 struct stat fst;
394 char fullpath[MAXPGPATH * 2];
395 char path[MAXPGPATH * 2];
396
397 if (strcmp(xlde->d_name, ".") == 0 ||
398 strcmp(xlde->d_name, "..") == 0)
399 continue;
400
401 snprintf(fullpath, sizeof(fullpath), "%s/%s", fullparentpath, xlde->d_name);
402
403 if (lstat(fullpath, &fst) < 0)
404 {
405 if (errno == ENOENT)
406 {
407 /*
408 * File doesn't exist anymore. This is ok, if the new primary
409 * is running and the file was just removed. If it was a data
410 * file, there should be a WAL record of the removal. If it
411 * was something else, it couldn't have been anyway.
412 *
413 * TODO: But complain if we're processing the target dir!
414 */
415 }
416 else
417 pg_fatal("could not stat file \"%s\": %m",
418 fullpath);
419 }
420
421 if (parentpath)
422 snprintf(path, sizeof(path), "%s/%s", parentpath, xlde->d_name);
423 else
424 snprintf(path, sizeof(path), "%s", xlde->d_name);
425
426 if (S_ISREG(fst.st_mode))
427 callback(path, FILE_TYPE_REGULAR, fst.st_size, NULL);
428 else if (S_ISDIR(fst.st_mode))
429 {
430 callback(path, FILE_TYPE_DIRECTORY, 0, NULL);
431 /* recurse to handle subdirectories */
433 }
434 else if (S_ISLNK(fst.st_mode))
435 {
436 char link_target[MAXPGPATH];
437 int len;
438
439 len = readlink(fullpath, link_target, sizeof(link_target));
440 if (len < 0)
441 pg_fatal("could not read symbolic link \"%s\": %m",
442 fullpath);
443 if (len >= sizeof(link_target))
444 pg_fatal("symbolic link \"%s\" target is too long",
445 fullpath);
446 link_target[len] = '\0';
447
448 callback(path, FILE_TYPE_SYMLINK, 0, link_target);
449
450 /*
451 * If it's a symlink within pg_tblspc, we need to recurse into it,
452 * to process all the tablespaces. We also follow a symlink if
453 * it's for pg_wal. Symlinks elsewhere are ignored.
454 */
455 if ((parentpath && strcmp(parentpath, PG_TBLSPC_DIR) == 0) ||
456 strcmp(path, "pg_wal") == 0)
458 }
459 }
460
461 if (errno)
462 pg_fatal("could not read directory \"%s\": %m",
463 fullparentpath);
464
465 if (closedir(xldir))
466 pg_fatal("could not close directory \"%s\": %m",
467 fullparentpath);
468}
int closedir(DIR *)
Definition: dirent.c:127
struct dirent * readdir(DIR *)
Definition: dirent.c:78
DIR * opendir(const char *)
Definition: dirent.c:33
static void recurse_dir(const char *datadir, const char *parentpath, process_file_callback_t callback)
Definition: file_ops.c:374
const void size_t len
char * datadir
#define PG_TBLSPC_DIR
Definition: relpath.h:41
Definition: dirent.c:26
Definition: dirent.h:10
char d_name[MAX_PATH]
Definition: dirent.h:15
static void callback(struct sockaddr *addr, struct sockaddr *mask, void *unused)
Definition: test_ifaddrs.c:46
#define lstat(path, sb)
Definition: win32_port.h:275
#define S_ISDIR(m)
Definition: win32_port.h:315
#define S_ISLNK(m)
Definition: win32_port.h:334
#define readlink(path, buf, size)
Definition: win32_port.h:226
#define S_ISREG(m)
Definition: win32_port.h:318

References callback(), closedir(), dirent::d_name, datadir, FILE_TYPE_DIRECTORY, FILE_TYPE_REGULAR, FILE_TYPE_SYMLINK, len, lstat, MAXPGPATH, opendir(), pg_fatal, PG_TBLSPC_DIR, readdir(), readlink, recurse_dir(), S_ISDIR, S_ISLNK, S_ISREG, snprintf, stat::st_mode, and stat::st_size.

Referenced by recurse_dir(), and traverse_datadir().

◆ remove_target()

void remove_target ( file_entry_t entry)

Definition at line 130 of file file_ops.c.

131{
133 Assert(entry->target_exists);
134
135 switch (entry->target_type)
136 {
138 remove_target_dir(entry->path);
139 break;
140
142 remove_target_file(entry->path, false);
143 break;
144
147 break;
148
150 pg_fatal("undefined file type for \"%s\"", entry->path);
151 break;
152 }
153}
void remove_target_file(const char *path, bool missing_ok)
Definition: file_ops.c:187
static void remove_target_dir(const char *path)
Definition: file_ops.c:243
static void remove_target_symlink(const char *path)
Definition: file_ops.c:271
@ FILE_ACTION_REMOVE
Definition: filemap.h:27
file_type_t target_type
Definition: filemap.h:60

References file_entry_t::action, Assert, FILE_ACTION_REMOVE, FILE_TYPE_DIRECTORY, FILE_TYPE_REGULAR, FILE_TYPE_SYMLINK, FILE_TYPE_UNDEFINED, file_entry_t::path, pg_fatal, remove_target_dir(), remove_target_file(), remove_target_symlink(), file_entry_t::target_exists, and file_entry_t::target_type.

Referenced by perform_rewind().

◆ remove_target_dir()

static void remove_target_dir ( const char *  path)
static

Definition at line 243 of file file_ops.c.

244{
245 char dstpath[MAXPGPATH];
246
247 if (dry_run)
248 return;
249
250 snprintf(dstpath, sizeof(dstpath), "%s/%s", datadir_target, path);
251 if (rmdir(dstpath) != 0)
252 pg_fatal("could not remove directory \"%s\": %m",
253 dstpath);
254}

References datadir_target, dry_run, dstpath, MAXPGPATH, pg_fatal, and snprintf.

Referenced by remove_target().

◆ remove_target_file()

void remove_target_file ( const char *  path,
bool  missing_ok 
)

Definition at line 187 of file file_ops.c.

188{
189 char dstpath[MAXPGPATH];
190
191 if (dry_run)
192 return;
193
194 snprintf(dstpath, sizeof(dstpath), "%s/%s", datadir_target, path);
195 if (unlink(dstpath) != 0)
196 {
197 if (errno == ENOENT && missing_ok)
198 return;
199
200 pg_fatal("could not remove file \"%s\": %m",
201 dstpath);
202 }
203}

References datadir_target, dry_run, dstpath, MAXPGPATH, pg_fatal, and snprintf.

Referenced by process_queued_fetch_requests(), and remove_target().

◆ remove_target_symlink()

static void remove_target_symlink ( const char *  path)
static

Definition at line 271 of file file_ops.c.

272{
273 char dstpath[MAXPGPATH];
274
275 if (dry_run)
276 return;
277
278 snprintf(dstpath, sizeof(dstpath), "%s/%s", datadir_target, path);
279 if (unlink(dstpath) != 0)
280 pg_fatal("could not remove symbolic link \"%s\": %m",
281 dstpath);
282}

References datadir_target, dry_run, dstpath, MAXPGPATH, pg_fatal, and snprintf.

Referenced by remove_target().

◆ slurpFile()

char * slurpFile ( const char *  datadir,
const char *  path,
size_t *  filesize 
)

Definition at line 314 of file file_ops.c.

315{
316 int fd;
317 char *buffer;
318 struct stat statbuf;
319 char fullpath[MAXPGPATH];
320 int len;
321 int r;
322
323 snprintf(fullpath, sizeof(fullpath), "%s/%s", datadir, path);
324
325 if ((fd = open(fullpath, O_RDONLY | PG_BINARY, 0)) == -1)
326 pg_fatal("could not open file \"%s\" for reading: %m",
327 fullpath);
328
329 if (fstat(fd, &statbuf) < 0)
330 pg_fatal("could not open file \"%s\" for reading: %m",
331 fullpath);
332
333 len = statbuf.st_size;
334
335 buffer = pg_malloc(len + 1);
336
337 r = read(fd, buffer, len);
338 if (r != len)
339 {
340 if (r < 0)
341 pg_fatal("could not read file \"%s\": %m",
342 fullpath);
343 else
344 pg_fatal("could not read file \"%s\": read %d of %zu",
345 fullpath, r, (Size) len);
346 }
347 close(fd);
348
349 /* Zero-terminate the buffer. */
350 buffer[len] = '\0';
351
352 if (filesize)
353 *filesize = len;
354 return buffer;
355}
size_t Size
Definition: c.h:562
void * pg_malloc(size_t size)
Definition: fe_memutils.c:47
#define read(a, b, c)
Definition: win32.h:13
static int fd(const char *x, int i)
Definition: preproc-init.c:105
#define fstat
Definition: win32_port.h:273

References close, datadir, fd(), fstat, len, MAXPGPATH, PG_BINARY, pg_fatal, pg_malloc(), read, snprintf, and stat::st_size.

Referenced by getTimelineHistory(), local_fetch_file(), and main().

◆ sync_target_dir()

void sync_target_dir ( void  )

Definition at line 294 of file file_ops.c.

295{
296 if (!do_sync || dry_run)
297 return;
298
299 sync_pgdata(datadir_target, PG_VERSION_NUM, sync_method);
300}
static bool do_sync
Definition: initdb.c:164
static DataDirSyncMethod sync_method
Definition: initdb.c:170

References datadir_target, do_sync, dry_run, and sync_method.

Referenced by main().

◆ traverse_datadir()

void traverse_datadir ( const char *  datadir,
process_file_callback_t  callback 
)

Definition at line 362 of file file_ops.c.

363{
365}

References callback(), datadir, and recurse_dir().

Referenced by local_traverse_files(), and main().

◆ truncate_target_file()

void truncate_target_file ( const char *  path,
off_t  newsize 
)

Definition at line 206 of file file_ops.c.

207{
208 char dstpath[MAXPGPATH];
209 int fd;
210
211 if (dry_run)
212 return;
213
214 snprintf(dstpath, sizeof(dstpath), "%s/%s", datadir_target, path);
215
216 fd = open(dstpath, O_WRONLY, pg_file_create_mode);
217 if (fd < 0)
218 pg_fatal("could not open file \"%s\" for truncation: %m",
219 dstpath);
220
221 if (ftruncate(fd, newsize) != 0)
222 pg_fatal("could not truncate file \"%s\" to %u: %m",
223 dstpath, (unsigned int) newsize);
224
225 close(fd);
226}

References close, datadir_target, dry_run, dstpath, fd(), MAXPGPATH, pg_fatal, pg_file_create_mode, and snprintf.

Referenced by perform_rewind().

◆ write_target_range()

void write_target_range ( char *  buf,
off_t  begin,
size_t  size 
)

Definition at line 88 of file file_ops.c.

89{
90 size_t writeleft;
91 char *p;
92
93 /* update progress report */
95 progress_report(false);
96
97 if (dry_run)
98 return;
99
100 if (lseek(dstfd, begin, SEEK_SET) == -1)
101 pg_fatal("could not seek in target file \"%s\": %m",
102 dstpath);
103
104 writeleft = size;
105 p = buf;
106 while (writeleft > 0)
107 {
108 ssize_t writelen;
109
110 errno = 0;
111 writelen = write(dstfd, p, writeleft);
112 if (writelen < 0)
113 {
114 /* if write didn't set errno, assume problem is no disk space */
115 if (errno == 0)
116 errno = ENOSPC;
117 pg_fatal("could not write file \"%s\": %m",
118 dstpath);
119 }
120
121 p += writelen;
122 writeleft -= writelen;
123 }
124
125 /* keep the file open, in case we need to copy more blocks in it */
126}
#define write(a, b, c)
Definition: win32.h:14
static void progress_report(uint64 relations_total, uint64 relations_checked, uint64 relpages_total, uint64 relpages_checked, const char *datname, bool force, bool finished)
Definition: pg_amcheck.c:1243
uint64 fetch_done
Definition: pg_rewind.c:86
static char * buf
Definition: pg_test_fsync.c:72
static pg_noinline void Size size
Definition: slab.c:607

References buf, dry_run, dstfd, dstpath, fetch_done, pg_fatal, progress_report(), size, and write.

Referenced by createBackupLabel(), local_queue_fetch_file(), local_queue_fetch_range(), and process_queued_fetch_requests().

Variable Documentation

◆ dstfd

int dstfd = -1
static

Definition at line 31 of file file_ops.c.

Referenced by close_target_file(), copy_file(), open_target_file(), and write_target_range().

◆ dstpath