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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-04 12:15:05 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-04 12:15:05 +0000 |
commit | 46651ce6fe013220ed397add242004d764fc0153 (patch) | |
tree | 6e5299f990f88e60174a1d3ae6e48eedd2688b2b /src/include/storage/fd.h | |
parent | Initial commit. (diff) | |
download | postgresql-14-46651ce6fe013220ed397add242004d764fc0153.tar.xz postgresql-14-46651ce6fe013220ed397add242004d764fc0153.zip |
Adding upstream version 14.5.upstream/14.5upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'src/include/storage/fd.h')
-rw-r--r-- | src/include/storage/fd.h | 181 |
1 files changed, 181 insertions, 0 deletions
diff --git a/src/include/storage/fd.h b/src/include/storage/fd.h new file mode 100644 index 0000000..5b3c280 --- /dev/null +++ b/src/include/storage/fd.h @@ -0,0 +1,181 @@ +/*------------------------------------------------------------------------- + * + * fd.h + * Virtual file descriptor definitions. + * + * + * Portions Copyright (c) 1996-2021, PostgreSQL Global Development Group + * Portions Copyright (c) 1994, Regents of the University of California + * + * src/include/storage/fd.h + * + *------------------------------------------------------------------------- + */ + +/* + * calls: + * + * File {Close, Read, Write, Size, Sync} + * {Path Name Open, Allocate, Free} File + * + * These are NOT JUST RENAMINGS OF THE UNIX ROUTINES. + * Use them for all file activity... + * + * File fd; + * fd = PathNameOpenFile("foo", O_RDONLY); + * + * AllocateFile(); + * FreeFile(); + * + * Use AllocateFile, not fopen, if you need a stdio file (FILE*); then + * use FreeFile, not fclose, to close it. AVOID using stdio for files + * that you intend to hold open for any length of time, since there is + * no way for them to share kernel file descriptors with other files. + * + * Likewise, use AllocateDir/FreeDir, not opendir/closedir, to allocate + * open directories (DIR*), and OpenTransientFile/CloseTransientFile for an + * unbuffered file descriptor. + * + * If you really can't use any of the above, at least call AcquireExternalFD + * or ReserveExternalFD to report any file descriptors that are held for any + * length of time. Failure to do so risks unnecessary EMFILE errors. + */ +#ifndef FD_H +#define FD_H + +#include <dirent.h> + +typedef enum RecoveryInitSyncMethod +{ + RECOVERY_INIT_SYNC_METHOD_FSYNC, + RECOVERY_INIT_SYNC_METHOD_SYNCFS +} RecoveryInitSyncMethod; + +struct iovec; /* avoid including port/pg_iovec.h here */ + +typedef int File; + + +/* GUC parameter */ +extern PGDLLIMPORT int max_files_per_process; +extern PGDLLIMPORT bool data_sync_retry; +extern int recovery_init_sync_method; + +/* + * This is private to fd.c, but exported for save/restore_backend_variables() + */ +extern int max_safe_fds; + +/* + * On Windows, we have to interpret EACCES as possibly meaning the same as + * ENOENT, because if a file is unlinked-but-not-yet-gone on that platform, + * that's what you get. Ugh. This code is designed so that we don't + * actually believe these cases are okay without further evidence (namely, + * a pending fsync request getting canceled ... see ProcessSyncRequests). + */ +#ifndef WIN32 +#define FILE_POSSIBLY_DELETED(err) ((err) == ENOENT) +#else +#define FILE_POSSIBLY_DELETED(err) ((err) == ENOENT || (err) == EACCES) +#endif + +/* + * prototypes for functions in fd.c + */ + +/* Operations on virtual Files --- equivalent to Unix kernel file ops */ +extern File PathNameOpenFile(const char *fileName, int fileFlags); +extern File PathNameOpenFilePerm(const char *fileName, int fileFlags, mode_t fileMode); +extern File OpenTemporaryFile(bool interXact); +extern void FileClose(File file); +extern int FilePrefetch(File file, off_t offset, int amount, uint32 wait_event_info); +extern int FileRead(File file, char *buffer, int amount, off_t offset, uint32 wait_event_info); +extern int FileWrite(File file, char *buffer, int amount, off_t offset, uint32 wait_event_info); +extern int FileSync(File file, uint32 wait_event_info); +extern off_t FileSize(File file); +extern int FileTruncate(File file, off_t offset, uint32 wait_event_info); +extern void FileWriteback(File file, off_t offset, off_t nbytes, uint32 wait_event_info); +extern char *FilePathName(File file); +extern int FileGetRawDesc(File file); +extern int FileGetRawFlags(File file); +extern mode_t FileGetRawMode(File file); + +/* Operations used for sharing named temporary files */ +extern File PathNameCreateTemporaryFile(const char *name, bool error_on_failure); +extern File PathNameOpenTemporaryFile(const char *path, int mode); +extern bool PathNameDeleteTemporaryFile(const char *name, bool error_on_failure); +extern void PathNameCreateTemporaryDir(const char *base, const char *name); +extern void PathNameDeleteTemporaryDir(const char *name); +extern void TempTablespacePath(char *path, Oid tablespace); + +/* Operations that allow use of regular stdio --- USE WITH CAUTION */ +extern FILE *AllocateFile(const char *name, const char *mode); +extern int FreeFile(FILE *file); + +/* Operations that allow use of pipe streams (popen/pclose) */ +extern FILE *OpenPipeStream(const char *command, const char *mode); +extern int ClosePipeStream(FILE *file); + +/* Operations to allow use of the <dirent.h> library routines */ +extern DIR *AllocateDir(const char *dirname); +extern struct dirent *ReadDir(DIR *dir, const char *dirname); +extern struct dirent *ReadDirExtended(DIR *dir, const char *dirname, + int elevel); +extern int FreeDir(DIR *dir); + +/* Operations to allow use of a plain kernel FD, with automatic cleanup */ +extern int OpenTransientFile(const char *fileName, int fileFlags); +extern int OpenTransientFilePerm(const char *fileName, int fileFlags, mode_t fileMode); +extern int CloseTransientFile(int fd); + +/* If you've really really gotta have a plain kernel FD, use this */ +extern int BasicOpenFile(const char *fileName, int fileFlags); +extern int BasicOpenFilePerm(const char *fileName, int fileFlags, mode_t fileMode); + +/* Use these for other cases, and also for long-lived BasicOpenFile FDs */ +extern bool AcquireExternalFD(void); +extern void ReserveExternalFD(void); +extern void ReleaseExternalFD(void); + +/* Make a directory with default permissions */ +extern int MakePGDirectory(const char *directoryName); + +/* Miscellaneous support routines */ +extern void InitFileAccess(void); +extern void set_max_safe_fds(void); +extern void closeAllVfds(void); +extern void SetTempTablespaces(Oid *tableSpaces, int numSpaces); +extern bool TempTablespacesAreSet(void); +extern int GetTempTablespaces(Oid *tableSpaces, int numSpaces); +extern Oid GetNextTempTableSpace(void); +extern void AtEOXact_Files(bool isCommit); +extern void AtEOSubXact_Files(bool isCommit, SubTransactionId mySubid, + SubTransactionId parentSubid); +extern void RemovePgTempFiles(void); +extern void RemovePgTempFilesInDir(const char *tmpdirname, bool missing_ok, + bool unlink_all); +extern bool looks_like_temp_rel_name(const char *name); + +extern int pg_fsync(int fd); +extern int pg_fsync_no_writethrough(int fd); +extern int pg_fsync_writethrough(int fd); +extern int pg_fdatasync(int fd); +extern void pg_flush_data(int fd, off_t offset, off_t amount); +extern ssize_t pg_pwritev_with_retry(int fd, + const struct iovec *iov, + int iovcnt, + off_t offset); +extern int pg_truncate(const char *path, off_t length); +extern void fsync_fname(const char *fname, bool isdir); +extern int fsync_fname_ext(const char *fname, bool isdir, bool ignore_perm, int elevel); +extern int durable_rename(const char *oldfile, const char *newfile, int loglevel); +extern int durable_unlink(const char *fname, int loglevel); +extern int durable_rename_excl(const char *oldfile, const char *newfile, int loglevel); +extern void SyncDataDirectory(void); +extern int data_sync_elevel(int elevel); + +/* Filename components */ +#define PG_TEMP_FILES_DIR "pgsql_tmp" +#define PG_TEMP_FILE_PREFIX "pgsql_tmp" + +#endif /* FD_H */ |