fd.c File Reference

#include "postgres.h"
#include <sys/file.h>
#include <sys/param.h>
#include <sys/stat.h>
#include <sys/mman.h>
#include <limits.h>
#include <unistd.h>
#include <fcntl.h>
#include "access/xact.h"
#include "access/xlog.h"
#include "catalog/pg_tablespace.h"
#include "common/file_perm.h"
#include "miscadmin.h"
#include "pgstat.h"
#include "portability/mem.h"
#include "storage/fd.h"
#include "storage/ipc.h"
#include "utils/guc.h"
#include "utils/resowner_private.h"

Include dependency graph for fd.c:

Go to the source code of this file.

Data Structures
struct	vfd
struct	AllocateDesc

Macros
#define	NUM_RESERVED_FDS   10
#define	FD_MINFREE   10
#define	DO_DB(A)   ((void) 0)
#define	VFD_CLOSED   (-1)
#define	FileIsValid(file)   ((file) > 0 && (file) < (int) SizeVfdCache && VfdCache[file].fileName != NULL)
#define	FileIsNotOpen(file)   (VfdCache[file].fd == VFD_CLOSED)
#define	FD_DELETE_AT_CLOSE   (1 << 0) /* T = delete when closed */
#define	FD_CLOSE_AT_EOXACT   (1 << 1) /* T = close at eoXact */
#define	FD_TEMP_FILE_LIMIT   (1 << 2) /* T = respect temp_file_limit */

Typedefs
typedef struct vfd	Vfd

Enumerations
enum	AllocateDescKind { AllocateDescFile, AllocateDescPipe, AllocateDescDir, AllocateDescRawFD }

Functions
static void	Delete (File file)
static void	LruDelete (File file)
static void	Insert (File file)
static int	LruInsert (File file)
static bool	ReleaseLruFile (void)
static void	ReleaseLruFiles (void)
static File	AllocateVfd (void)
static void	FreeVfd (File file)
static int	FileAccess (File file)
static File	OpenTemporaryFileInTablespace (Oid tblspcOid, bool rejectError)
static bool	reserveAllocatedDesc (void)
static int	FreeDesc (AllocateDesc *desc)
static void	AtProcExit_Files (int code, Datum arg)
static void	CleanupTempFiles (bool isCommit, bool isProcExit)
static void	RemovePgTempRelationFiles (const char *tsdirname)
static void	RemovePgTempRelationFilesInDbspace (const char *dbspacedirname)
static void	walkdir (const char *path, void(*action)(const char *fname, bool isdir, int elevel), bool process_symlinks, int elevel)
static void	datadir_fsync_fname (const char *fname, bool isdir, int elevel)
static void	unlink_if_exists_fname (const char *fname, bool isdir, int elevel)
static int	fsync_fname_ext (const char *fname, bool isdir, bool ignore_perm, int elevel)
static int	fsync_parent_path (const char *fname, int elevel)
int	pg_fsync (int fd)
int	pg_fsync_no_writethrough (int fd)
int	pg_fsync_writethrough (int fd)
int	pg_fdatasync (int fd)
void	pg_flush_data (int fd, off_t offset, off_t nbytes)
void	fsync_fname (const char *fname, bool isdir)
int	durable_rename (const char *oldfile, const char *newfile, int elevel)
int	durable_unlink (const char *fname, int elevel)
int	durable_link_or_rename (const char *oldfile, const char *newfile, int elevel)
void	InitFileAccess (void)
static void	count_usable_fds (int max_to_probe, int *usable_fds, int *already_open)
void	set_max_safe_fds (void)
int	BasicOpenFile (const char *fileName, int fileFlags)
int	BasicOpenFilePerm (const char *fileName, int fileFlags, mode_t fileMode)
static void	ReportTemporaryFileUsage (const char *path, off_t size)
static void	RegisterTemporaryFile (File file)
File	PathNameOpenFile (const char *fileName, int fileFlags)
File	PathNameOpenFilePerm (const char *fileName, int fileFlags, mode_t fileMode)
void	PathNameCreateTemporaryDir (const char *basedir, const char *directory)
void	PathNameDeleteTemporaryDir (const char *dirname)
File	OpenTemporaryFile (bool interXact)
void	TempTablespacePath (char *path, Oid tablespace)
File	PathNameCreateTemporaryFile (const char *path, bool error_on_failure)
File	PathNameOpenTemporaryFile (const char *path)
bool	PathNameDeleteTemporaryFile (const char *path, bool error_on_failure)
void	FileClose (File file)
int	FilePrefetch (File file, off_t offset, int amount, uint32 wait_event_info)
void	FileWriteback (File file, off_t offset, off_t nbytes, uint32 wait_event_info)
int	FileRead (File file, char *buffer, int amount, off_t offset, uint32 wait_event_info)
int	FileWrite (File file, char *buffer, int amount, off_t offset, uint32 wait_event_info)
int	FileSync (File file, uint32 wait_event_info)
off_t	FileSize (File file)
int	FileTruncate (File file, off_t offset, uint32 wait_event_info)
char *	FilePathName (File file)
int	FileGetRawDesc (File file)
int	FileGetRawFlags (File file)
mode_t	FileGetRawMode (File file)
FILE *	AllocateFile (const char *name, const char *mode)
int	OpenTransientFile (const char *fileName, int fileFlags)
int	OpenTransientFilePerm (const char *fileName, int fileFlags, mode_t fileMode)
FILE *	OpenPipeStream (const char *command, const char *mode)
int	FreeFile (FILE *file)
int	CloseTransientFile (int fd)
DIR *	AllocateDir (const char *dirname)
struct dirent *	ReadDir (DIR *dir, const char *dirname)
struct dirent *	ReadDirExtended (DIR *dir, const char *dirname, int elevel)
int	FreeDir (DIR *dir)
int	ClosePipeStream (FILE *file)
void	closeAllVfds (void)
void	SetTempTablespaces (Oid *tableSpaces, int numSpaces)
bool	TempTablespacesAreSet (void)
int	GetTempTablespaces (Oid *tableSpaces, int numSpaces)
Oid	GetNextTempTableSpace (void)
void	AtEOSubXact_Files (bool isCommit, SubTransactionId mySubid, SubTransactionId parentSubid)
void	AtEOXact_Files (bool isCommit)
void	RemovePgTempFiles (void)
void	RemovePgTempFilesInDir (const char *tmpdirname, bool missing_ok, bool unlink_all)
bool	looks_like_temp_rel_name (const char *name)
void	SyncDataDirectory (void)
int	MakePGDirectory (const char *directoryName)
int	data_sync_elevel (int elevel)

Variables
int	max_files_per_process = 1000
int	max_safe_fds = 32
bool	data_sync_retry = false
static Vfd *	VfdCache
static Size	SizeVfdCache = 0
static int	nfile = 0
static bool	have_xact_temporary_files = false
static uint64	temporary_files_size = 0
static int	numAllocatedDescs = 0
static int	maxAllocatedDescs = 0
static AllocateDesc *	allocatedDescs = NULL
static long	tempFileCounter = 0
static Oid *	tempTableSpaces = NULL
static int	numTempTableSpaces = -1
static int	nextTempTableSpace = 0

Macro Definition Documentation

DO_DB

#define DO_DB

(

A

)

((void) 0)

Definition at line 160 of file fd.c.

Referenced by AllocateDir(), AllocateFile(), AllocateVfd(), ClosePipeStream(), CloseTransientFile(), Delete(), FileAccess(), FileClose(), FilePrefetch(), FileRead(), FileSize(), FileSync(), FileTruncate(), FileWrite(), FileWriteback(), FreeDir(), FreeFile(), FreeVfd(), Insert(), LruDelete(), LruInsert(), OpenPipeStream(), OpenTransientFilePerm(), PathNameOpenFilePerm(), and ReleaseLruFile().

FD_CLOSE_AT_EOXACT

#define FD_CLOSE_AT_EOXACT   (1 << 1) /* T = close at eoXact */

Definition at line 173 of file fd.c.

Referenced by CleanupTempFiles(), and RegisterTemporaryFile().

FD_DELETE_AT_CLOSE

#define FD_DELETE_AT_CLOSE   (1 << 0) /* T = delete when closed */

Definition at line 172 of file fd.c.

Referenced by CleanupTempFiles(), FileClose(), and OpenTemporaryFile().

FD_MINFREE

#define FD_MINFREE   10

Definition at line 124 of file fd.c.

Referenced by reserveAllocatedDesc(), and set_max_safe_fds().

FD_TEMP_FILE_LIMIT

#define FD_TEMP_FILE_LIMIT   (1 << 2) /* T = respect temp_file_limit */

Definition at line 174 of file fd.c.

Referenced by FileClose(), FileTruncate(), FileWrite(), LruDelete(), OpenTemporaryFile(), and PathNameCreateTemporaryFile().

FileIsNotOpen

#define FileIsNotOpen

(

file

)

(VfdCache[file].fd == VFD_CLOSED)

Definition at line 169 of file fd.c.

Referenced by CleanupTempFiles(), closeAllVfds(), FileAccess(), FileClose(), FileSize(), LruInsert(), and RegisterTemporaryFile().

FileIsValid

#define FileIsValid

(

file

)

((file) > 0 && (file) < (int) SizeVfdCache && VfdCache[file].fileName != NULL)

Definition at line 166 of file fd.c.

Referenced by FileClose(), FileGetRawDesc(), FileGetRawFlags(), FileGetRawMode(), FilePathName(), FilePrefetch(), FileRead(), FileSize(), FileSync(), FileTruncate(), FileWrite(), FileWriteback(), and RegisterTemporaryFile().

NUM_RESERVED_FDS

#define NUM_RESERVED_FDS   10

Definition at line 118 of file fd.c.

Referenced by set_max_safe_fds().

VFD_CLOSED

#define VFD_CLOSED   (-1)

Definition at line 164 of file fd.c.

Referenced by AllocateVfd(), FileClose(), InitFileAccess(), and LruDelete().

Typedef Documentation

Vfd

typedef struct vfd Vfd

Enumeration Type Documentation

AllocateDescKind

enum AllocateDescKind

Enumerator
AllocateDescFile
AllocateDescPipe
AllocateDescDir
AllocateDescRawFD

Definition at line 222 of file fd.c.

{
    AllocateDescFile,
    AllocateDescPipe,
    AllocateDescDir,
    AllocateDescRawFD
} AllocateDescKind;

Function Documentation

AllocateDir()

DIR* AllocateDir

(

const char *

dirname

)

Definition at line 2503 of file fd.c.

References AllocateDescDir, AllocateDesc::create_subid, AllocateDesc::desc, AllocateDesc::dir, DO_DB, elog, ereport, errcode(), errmsg(), ERROR, GetCurrentSubTransactionId(), AllocateDesc::kind, LOG, maxAllocatedDescs, numAllocatedDescs, opendir(), ReleaseLruFile(), ReleaseLruFiles(), and reserveAllocatedDesc().

Referenced by calculate_database_size(), calculate_tablespace_size(), CheckPointLogicalRewriteHeap(), CheckPointSnapBuild(), CleanupBackupHistory(), copydir(), db_dir_size(), DeleteAllExportedSnapshotFiles(), destroy_tablespace_directories(), directory_is_empty(), do_pg_start_backup(), dsm_cleanup_for_mmap(), get_ext_ver_list(), getInstallationPaths(), movedb(), ParseTzFile(), perform_base_backup(), pg_available_extension_versions(), pg_available_extensions(), pg_logdir_ls_internal(), pg_ls_dir(), pg_ls_dir_files(), pg_tablespace_databases(), pg_tzenumerate_next(), pg_tzenumerate_start(), pgarch_readyXlog(), pgstat_reset_remove_files(), RelationCacheInitFileRemove(), RelationCacheInitFileRemoveInDir(), RemoveNonParentXlogFiles(), RemoveOldXlogFiles(), RemovePgTempFiles(), RemovePgTempFilesInDir(), RemovePgTempRelationFiles(), RemovePgTempRelationFilesInDbspace(), RemoveTempXlogFiles(), ReorderBufferCleanupSerializedTXNs(), ResetUnloggedRelations(), ResetUnloggedRelationsInDbspaceDir(), ResetUnloggedRelationsInTablespaceDir(), restoreTwoPhaseData(), scan_directory_ci(), sendDir(), SlruScanDirectory(), StartupReorderBuffer(), StartupReplicationSlots(), UpdateLogicalMappings(), and walkdir().

{
    DIR        *dir;

    DO_DB(elog(LOG, "AllocateDir: Allocated %d (%s)",
               numAllocatedDescs, dirname));

    /* Can we allocate another non-virtual FD? */
    if (!reserveAllocatedDesc())
        ereport(ERROR,
                (errcode(ERRCODE_INSUFFICIENT_RESOURCES),
                 errmsg("exceeded maxAllocatedDescs (%d) while trying to open directory \"%s\"",
                        maxAllocatedDescs, dirname)));

    /* Close excess kernel FDs. */
    ReleaseLruFiles();

TryAgain:
    if ((dir = opendir(dirname)) != NULL)
    {
        AllocateDesc *desc = &allocatedDescs[numAllocatedDescs];

        desc->kind = AllocateDescDir;
        desc->desc.dir = dir;
        desc->create_subid = GetCurrentSubTransactionId();
        numAllocatedDescs++;
        return desc->desc.dir;
    }

    if (errno == EMFILE || errno == ENFILE)
    {
        int         save_errno = errno;

        ereport(LOG,
                (errcode(ERRCODE_INSUFFICIENT_RESOURCES),
                 errmsg("out of file descriptors: %m; release and retry")));
        errno = 0;
        if (ReleaseLruFile())
            goto TryAgain;
        errno = save_errno;
    }

    return NULL;
}

AllocateFile()

FILE* AllocateFile	(	const char *	name,
		const char *	mode
	)

Definition at line 2242 of file fd.c.

References AllocateDescFile, AllocateDesc::create_subid, AllocateDesc::desc, DO_DB, elog, ereport, errcode(), errmsg(), ERROR, AllocateDesc::file, GetCurrentSubTransactionId(), AllocateDesc::kind, LOG, maxAllocatedDescs, numAllocatedDescs, ReleaseLruFile(), ReleaseLruFiles(), and reserveAllocatedDesc().

Referenced by _ShowOption(), AlterSystemSetConfigFile(), apw_dump_now(), apw_load_buffers(), BackendRun(), BeginCopyFrom(), BeginCopyTo(), checkControlFile(), do_pg_start_backup(), do_pg_stop_backup(), entry_reset(), existsTimeLineHistory(), ExportSnapshot(), fill_hba_view(), gc_qtexts(), ImportSnapshot(), load_dh_file(), load_hba(), load_ident(), load_relcache_init_file(), parse_extension_control_file(), ParseTzFile(), perform_base_backup(), pg_backup_start_time(), pg_current_logfile(), pg_file_write_internal(), pg_promote(), PGSharedMemoryAttach(), pgss_shmem_shutdown(), pgss_shmem_startup(), pgstat_read_db_statsfile(), pgstat_read_db_statsfile_timestamp(), pgstat_read_statsfiles(), pgstat_write_db_statsfile(), pgstat_write_statsfiles(), PostmasterMarkPIDForWorkerNotify(), read_backup_label(), read_binary_file(), read_tablespace_map(), read_whole_file(), readTimeLineHistory(), sendFile(), tokenize_inc_file(), tsearch_readline_begin(), ValidatePgVersion(), write_relcache_init_file(), XLogArchiveForceDone(), and XLogArchiveNotify().

{
    FILE       *file;

    DO_DB(elog(LOG, "AllocateFile: Allocated %d (%s)",
               numAllocatedDescs, name));

    /* Can we allocate another non-virtual FD? */
    if (!reserveAllocatedDesc())
        ereport(ERROR,
                (errcode(ERRCODE_INSUFFICIENT_RESOURCES),
                 errmsg("exceeded maxAllocatedDescs (%d) while trying to open file \"%s\"",
                        maxAllocatedDescs, name)));

    /* Close excess kernel FDs. */
    ReleaseLruFiles();

TryAgain:
    if ((file = fopen(name, mode)) != NULL)
    {
        AllocateDesc *desc = &allocatedDescs[numAllocatedDescs];

        desc->kind = AllocateDescFile;
        desc->desc.file = file;
        desc->create_subid = GetCurrentSubTransactionId();
        numAllocatedDescs++;
        return desc->desc.file;
    }

    if (errno == EMFILE || errno == ENFILE)
    {
        int         save_errno = errno;

        ereport(LOG,
                (errcode(ERRCODE_INSUFFICIENT_RESOURCES),
                 errmsg("out of file descriptors: %m; release and retry")));
        errno = 0;
        if (ReleaseLruFile())
            goto TryAgain;
        errno = save_errno;
    }

    return NULL;
}

AllocateVfd()

static File AllocateVfd ( void  )

static

Definition at line 1197 of file fd.c.

References Assert, DO_DB, elog, ereport, errcode(), errmsg(), ERROR, vfd::fd, i, LOG, MemSet, vfd::nextFree, realloc, SizeVfdCache, and VFD_CLOSED.

Referenced by PathNameOpenFilePerm().

{
    Index       i;
    File        file;

    DO_DB(elog(LOG, "AllocateVfd. Size %zu", SizeVfdCache));

    Assert(SizeVfdCache > 0);   /* InitFileAccess not called? */

    if (VfdCache[0].nextFree == 0)
    {
        /*
         * The free list is empty so it is time to increase the size of the
         * array.  We choose to double it each time this happens. However,
         * there's not much point in starting *real* small.
         */
        Size        newCacheSize = SizeVfdCache * 2;
        Vfd        *newVfdCache;

        if (newCacheSize < 32)
            newCacheSize = 32;

        /*
         * Be careful not to clobber VfdCache ptr if realloc fails.
         */
        newVfdCache = (Vfd *) realloc(VfdCache, sizeof(Vfd) * newCacheSize);
        if (newVfdCache == NULL)
            ereport(ERROR,
                    (errcode(ERRCODE_OUT_OF_MEMORY),
                     errmsg("out of memory")));
        VfdCache = newVfdCache;

        /*
         * Initialize the new entries and link them into the free list.
         */
        for (i = SizeVfdCache; i < newCacheSize; i++)
        {
            MemSet((char *) &(VfdCache[i]), 0, sizeof(Vfd));
            VfdCache[i].nextFree = i + 1;
            VfdCache[i].fd = VFD_CLOSED;
        }
        VfdCache[newCacheSize - 1].nextFree = 0;
        VfdCache[0].nextFree = SizeVfdCache;

        /*
         * Record the new size
         */
        SizeVfdCache = newCacheSize;
    }

    file = VfdCache[0].nextFree;

    VfdCache[0].nextFree = VfdCache[file].nextFree;

    return file;
}

AtEOSubXact_Files()

void AtEOSubXact_Files	(	bool	isCommit,
		SubTransactionId	mySubid,
		SubTransactionId	parentSubid
	)

Definition at line 2785 of file fd.c.

References AllocateDesc::create_subid, FreeDesc(), i, and numAllocatedDescs.

Referenced by AbortSubTransaction(), and CommitSubTransaction().

{
    Index       i;

    for (i = 0; i < numAllocatedDescs; i++)
    {
        if (allocatedDescs[i].create_subid == mySubid)
        {
            if (isCommit)
                allocatedDescs[i].create_subid = parentSubid;
            else
            {
                /* have to recheck the item after FreeDesc (ugly) */
                FreeDesc(&allocatedDescs[i--]);
            }
        }
    }
}

AtEOXact_Files()

void AtEOXact_Files

(

bool

isCommit

)

Definition at line 2818 of file fd.c.

References CleanupTempFiles(), numTempTableSpaces, and tempTableSpaces.

Referenced by AbortTransaction(), AutoVacLauncherMain(), BackgroundWriterMain(), CheckpointerMain(), CommitTransaction(), PrepareTransaction(), and WalWriterMain().

{
    CleanupTempFiles(isCommit, false);
    tempTableSpaces = NULL;
    numTempTableSpaces = -1;
}

AtProcExit_Files()

static void AtProcExit_Files ( int  code, Datum  arg  )

static

Definition at line 2832 of file fd.c.

References CleanupTempFiles().

Referenced by InitFileAccess().

{
    CleanupTempFiles(false, true);
}

BasicOpenFile()

int BasicOpenFile	(	const char *	fileName,
		int	fileFlags
	)

Definition at line 981 of file fd.c.

References BasicOpenFilePerm(), and pg_file_create_mode.

Referenced by AlterSystemSetConfigFile(), ReadControlFile(), update_controlfile(), wal_segment_open(), WalSndSegmentOpen(), WriteControlFile(), XLogFileInit(), XLogFileOpen(), and XLogFileRead().

{
    return BasicOpenFilePerm(fileName, fileFlags, pg_file_create_mode);
}

BasicOpenFilePerm()

int BasicOpenFilePerm	(	const char *	fileName,
		int	fileFlags,
		mode_t	fileMode
	)

Definition at line 1003 of file fd.c.

References buf, elog, ereport, errcode(), errmsg(), vfd::fd, LOG, vfd::lruLessRecently, ReleaseLruFile(), and snprintf.

Referenced by BasicOpenFile(), LruInsert(), OpenTransientFilePerm(), PathNameOpenFilePerm(), and readRecoverySignalFile().

{
    int         fd;

tryAgain:
    fd = open(fileName, fileFlags, fileMode);

    if (fd >= 0)
        return fd;              /* success! */

    if (errno == EMFILE || errno == ENFILE)
    {
        int         save_errno = errno;

        ereport(LOG,
                (errcode(ERRCODE_INSUFFICIENT_RESOURCES),
                 errmsg("out of file descriptors: %m; release and retry")));
        errno = 0;
        if (ReleaseLruFile())
            goto tryAgain;
        errno = save_errno;
    }

    return -1;                  /* failure */
}

CleanupTempFiles()

static void CleanupTempFiles ( bool  isCommit, bool  isProcExit  )

static

Definition at line 2850 of file fd.c.

References Assert, elog, FD_CLOSE_AT_EOXACT, FD_DELETE_AT_CLOSE, vfd::fdstate, FileClose(), FileIsNotOpen, vfd::fileName, FreeDesc(), have_xact_temporary_files, i, numAllocatedDescs, SizeVfdCache, and WARNING.

Referenced by AtEOXact_Files(), and AtProcExit_Files().

{
    Index       i;

    /*
     * Careful here: at proc_exit we need extra cleanup, not just
     * xact_temporary files.
     */
    if (isProcExit || have_xact_temporary_files)
    {
        Assert(FileIsNotOpen(0));   /* Make sure ring not corrupted */
        for (i = 1; i < SizeVfdCache; i++)
        {
            unsigned short fdstate = VfdCache[i].fdstate;

            if (((fdstate & FD_DELETE_AT_CLOSE) || (fdstate & FD_CLOSE_AT_EOXACT)) &&
                VfdCache[i].fileName != NULL)
            {
                /*
                 * If we're in the process of exiting a backend process, close
                 * all temporary files. Otherwise, only close temporary files
                 * local to the current transaction. They should be closed by
                 * the ResourceOwner mechanism already, so this is just a
                 * debugging cross-check.
                 */
                if (isProcExit)
                    FileClose(i);
                else if (fdstate & FD_CLOSE_AT_EOXACT)
                {
                    elog(WARNING,
                         "temporary file %s not closed at end-of-transaction",
                         VfdCache[i].fileName);
                    FileClose(i);
                }
            }
        }

        have_xact_temporary_files = false;
    }

    /* Complain if any allocated files remain open at commit. */
    if (isCommit && numAllocatedDescs > 0)
        elog(WARNING, "%d temporary files and directories not closed at end-of-transaction",
             numAllocatedDescs);

    /* Clean up "allocated" stdio files, dirs and fds. */
    while (numAllocatedDescs > 0)
        FreeDesc(&allocatedDescs[0]);
}

closeAllVfds()

void closeAllVfds

(

void

)

Definition at line 2680 of file fd.c.

References Assert, FileIsNotOpen, i, LruDelete(), and SizeVfdCache.

Referenced by standard_ProcessUtility().

{
    Index       i;

    if (SizeVfdCache > 0)
    {
        Assert(FileIsNotOpen(0));   /* Make sure ring not corrupted */
        for (i = 1; i < SizeVfdCache; i++)
        {
            if (!FileIsNotOpen(i))
                LruDelete(i);
        }
    }
}

ClosePipeStream()

int ClosePipeStream

(

FILE *

file

)

Definition at line 2651 of file fd.c.

References AllocateDescPipe, AllocateDesc::desc, DO_DB, elog, AllocateDesc::file, FreeDesc(), i, AllocateDesc::kind, LOG, numAllocatedDescs, and WARNING.

Referenced by ClosePipeToProgram(), pg_import_system_collations(), and run_ssl_passphrase_command().

{
    int         i;

    DO_DB(elog(LOG, "ClosePipeStream: Allocated %d", numAllocatedDescs));

    /* Remove file from list of allocated files, if it's present */
    for (i = numAllocatedDescs; --i >= 0;)
    {
        AllocateDesc *desc = &allocatedDescs[i];

        if (desc->kind == AllocateDescPipe && desc->desc.file == file)
            return FreeDesc(desc);
    }

    /* Only get here if someone passes us a file not in allocatedDescs */
    elog(WARNING, "file passed to ClosePipeStream was not obtained from OpenPipeStream");

    return pclose(file);
}

CloseTransientFile()

int CloseTransientFile

(

int

fd

)

Definition at line 2469 of file fd.c.

References AllocateDescRawFD, close, AllocateDesc::desc, DO_DB, elog, AllocateDesc::fd, FreeDesc(), i, AllocateDesc::kind, LOG, numAllocatedDescs, and WARNING.

Referenced by ApplyLogicalMappingFile(), be_lo_export(), CheckPointLogicalRewriteHeap(), CheckPointReplicationOrigin(), copy_file(), dsm_impl_mmap(), durable_rename(), fsync_fname_ext(), get_controlfile(), heap_xlog_logical_rewrite(), lo_import_internal(), load_relmap_file(), mdunlinkfork(), qtext_load_file(), qtext_store(), ReadTwoPhaseFile(), RecreateTwoPhaseFile(), ReorderBufferSerializeChange(), ReorderBufferSerializeTXN(), RestoreSlotFromDisk(), SaveSlotToPath(), SendTimeLineHistory(), SimpleLruDoesPhysicalPageExist(), SimpleLruFlush(), SlruInternalWritePage(), SlruPhysicalReadPage(), SlruPhysicalWritePage(), SnapBuildRestore(), SnapBuildSerialize(), StartupReplicationOrigin(), walkdir(), write_relmap_file(), writeTimeLineHistory(), writeTimeLineHistoryFile(), and XLogFileCopy().

{
    int         i;

    DO_DB(elog(LOG, "CloseTransientFile: Allocated %d", numAllocatedDescs));

    /* Remove fd from list of allocated files, if it's present */
    for (i = numAllocatedDescs; --i >= 0;)
    {
        AllocateDesc *desc = &allocatedDescs[i];

        if (desc->kind == AllocateDescRawFD && desc->desc.fd == fd)
            return FreeDesc(desc);
    }

    /* Only get here if someone passes us a file not in allocatedDescs */
    elog(WARNING, "fd passed to CloseTransientFile was not obtained from OpenTransientFile");

    return close(fd);
}

count_usable_fds()

static void count_usable_fds ( int  max_to_probe, int *  usable_fds, int *  already_open  )

static

Definition at line 854 of file fd.c.

References close, elog, ereport, errmsg(), vfd::fd, palloc(), pfree(), repalloc(), and WARNING.

Referenced by set_max_safe_fds().

{
    int        *fd;
    int         size;
    int         used = 0;
    int         highestfd = 0;
    int         j;

#ifdef HAVE_GETRLIMIT
    struct rlimit rlim;
    int         getrlimit_status;
#endif

    size = 1024;
    fd = (int *) palloc(size * sizeof(int));

#ifdef HAVE_GETRLIMIT
#ifdef RLIMIT_NOFILE            /* most platforms use RLIMIT_NOFILE */
    getrlimit_status = getrlimit(RLIMIT_NOFILE, &rlim);
#else                           /* but BSD doesn't ... */
    getrlimit_status = getrlimit(RLIMIT_OFILE, &rlim);
#endif                          /* RLIMIT_NOFILE */
    if (getrlimit_status != 0)
        ereport(WARNING, (errmsg("getrlimit failed: %m")));
#endif                          /* HAVE_GETRLIMIT */

    /* dup until failure or probe limit reached */
    for (;;)
    {
        int         thisfd;

#ifdef HAVE_GETRLIMIT

        /*
         * don't go beyond RLIMIT_NOFILE; causes irritating kernel logs on
         * some platforms
         */
        if (getrlimit_status == 0 && highestfd >= rlim.rlim_cur - 1)
            break;
#endif

        thisfd = dup(0);
        if (thisfd < 0)
        {
            /* Expect EMFILE or ENFILE, else it's fishy */
            if (errno != EMFILE && errno != ENFILE)
                elog(WARNING, "dup(0) failed after %d successes: %m", used);
            break;
        }

        if (used >= size)
        {
            size *= 2;
            fd = (int *) repalloc(fd, size * sizeof(int));
        }
        fd[used++] = thisfd;

        if (highestfd < thisfd)
            highestfd = thisfd;

        if (used >= max_to_probe)
            break;
    }

    /* release the files we opened */
    for (j = 0; j < used; j++)
        close(fd[j]);

    pfree(fd);

    /*
     * Return results.  usable_fds is just the number of successful dups. We
     * assume that the system limit is highestfd+1 (remember 0 is a legal FD
     * number) and so already_open is highestfd+1 - usable_fds.
     */
    *usable_fds = used;
    *already_open = highestfd + 1 - used;
}

data_sync_elevel()

int data_sync_elevel

(

int

elevel

)

Definition at line 3519 of file fd.c.

References data_sync_retry, elevel, and PANIC.

Referenced by CheckPointLogicalRewriteHeap(), FileClose(), fsync_fname(), heap_xlog_logical_rewrite(), logical_end_heap_rewrite(), LruDelete(), mdimmedsync(), pg_flush_data(), ProcessSyncRequests(), register_dirty_segment(), SlruReportIOError(), write_relmap_file(), writeTimeLineHistory(), writeTimeLineHistoryFile(), and XLogFileCopy().

{
    return data_sync_retry ? elevel : PANIC;
}

datadir_fsync_fname()

static void datadir_fsync_fname ( const char *  fname, bool  isdir, int  elevel  )

static

Definition at line 3345 of file fd.c.

References fsync_fname_ext().

Referenced by SyncDataDirectory().

{
    /*
     * We want to silently ignoring errors about unreadable files.  Pass that
     * desire on to fsync_fname_ext().
     */
    fsync_fname_ext(fname, isdir, true, elevel);
}

Delete()

static void Delete ( File  file )

static

Definition at line 1051 of file fd.c.

References Assert, DO_DB, elog, vfd::fileName, LOG, vfd::lruLessRecently, and vfd::lruMoreRecently.

Referenced by FileAccess(), FileClose(), and LruDelete().

{
    Vfd        *vfdP;

    Assert(file != 0);

    DO_DB(elog(LOG, "Delete %d (%s)",
               file, VfdCache[file].fileName));
    DO_DB(_dump_lru());

    vfdP = &VfdCache[file];

    VfdCache[vfdP->lruLessRecently].lruMoreRecently = vfdP->lruMoreRecently;
    VfdCache[vfdP->lruMoreRecently].lruLessRecently = vfdP->lruLessRecently;

    DO_DB(_dump_lru());
}

durable_link_or_rename()

int durable_link_or_rename	(	const char *	oldfile,
		const char *	newfile,
		int	elevel
	)

Definition at line 769 of file fd.c.

References ereport, errcode_for_file_access(), errmsg(), fsync_fname_ext(), fsync_parent_path(), and link().

Referenced by InstallXLogFileSegment(), writeTimeLineHistory(), and writeTimeLineHistoryFile().

{
    /*
     * Ensure that, if we crash directly after the rename/link, a file with
     * valid contents is moved into place.
     */
    if (fsync_fname_ext(oldfile, false, false, elevel) != 0)
        return -1;

#ifdef HAVE_WORKING_LINK
    if (link(oldfile, newfile) < 0)
    {
        ereport(elevel,
                (errcode_for_file_access(),
                 errmsg("could not link file \"%s\" to \"%s\": %m",
                        oldfile, newfile)));
        return -1;
    }
    unlink(oldfile);
#else
    /* XXX: Add racy file existence check? */
    if (rename(oldfile, newfile) < 0)
    {
        ereport(elevel,
                (errcode_for_file_access(),
                 errmsg("could not rename file \"%s\" to \"%s\": %m",
                        oldfile, newfile)));
        return -1;
    }
#endif

    /*
     * Make change persistent in case of an OS crash, both the new entry and
     * its parent directory need to be flushed.
     */
    if (fsync_fname_ext(newfile, false, false, elevel) != 0)
        return -1;

    /* Same for parent directory */
    if (fsync_parent_path(newfile, elevel) != 0)
        return -1;

    return 0;
}

durable_rename()

int durable_rename	(	const char *	oldfile,
		const char *	newfile,
		int	elevel
	)

Definition at line 643 of file fd.c.

References CloseTransientFile(), ereport, errcode_for_file_access(), errmsg(), vfd::fd, fsync_fname_ext(), fsync_parent_path(), OpenTransientFile(), PG_BINARY, and pg_fsync().

Referenced by AlterSystemSetConfigFile(), apw_dump_now(), CancelBackup(), CheckPointReplicationOrigin(), dir_close(), KeepFileRestoredFromArchive(), pgarch_archiveDone(), pgss_shmem_shutdown(), StartupXLOG(), and XLogArchiveForceDone().

{
    int         fd;

    /*
     * First fsync the old and target path (if it exists), to ensure that they
     * are properly persistent on disk. Syncing the target file is not
     * strictly necessary, but it makes it easier to reason about crashes;
     * because it's then guaranteed that either source or target file exists
     * after a crash.
     */
    if (fsync_fname_ext(oldfile, false, false, elevel) != 0)
        return -1;

    fd = OpenTransientFile(newfile, PG_BINARY | O_RDWR);
    if (fd < 0)
    {
        if (errno != ENOENT)
        {
            ereport(elevel,
                    (errcode_for_file_access(),
                     errmsg("could not open file \"%s\": %m", newfile)));
            return -1;
        }
    }
    else
    {
        if (pg_fsync(fd) != 0)
        {
            int         save_errno;

            /* close file upon error, might not be in transaction context */
            save_errno = errno;
            CloseTransientFile(fd);
            errno = save_errno;

            ereport(elevel,
                    (errcode_for_file_access(),
                     errmsg("could not fsync file \"%s\": %m", newfile)));
            return -1;
        }

        if (CloseTransientFile(fd) != 0)
        {
            ereport(elevel,
                    (errcode_for_file_access(),
                     errmsg("could not close file \"%s\": %m", newfile)));
            return -1;
        }
    }

    /* Time to do the real deal... */
    if (rename(oldfile, newfile) < 0)
    {
        ereport(elevel,
                (errcode_for_file_access(),
                 errmsg("could not rename file \"%s\" to \"%s\": %m",
                        oldfile, newfile)));
        return -1;
    }

    /*
     * To guarantee renaming the file is persistent, fsync the file with its
     * new name, and its containing directory.
     */
    if (fsync_fname_ext(newfile, false, false, elevel) != 0)
        return -1;

    if (fsync_parent_path(newfile, elevel) != 0)
        return -1;

    return 0;
}

durable_unlink()

int durable_unlink	(	const char *	fname,
		int	elevel
	)

Definition at line 733 of file fd.c.

References ereport, errcode_for_file_access(), errmsg(), and fsync_parent_path().

Referenced by do_pg_stop_backup(), exitArchiveRecovery(), InstallXLogFileSegment(), and RemoveXlogFile().

{
    if (unlink(fname) < 0)
    {
        ereport(elevel,
                (errcode_for_file_access(),
                 errmsg("could not remove file \"%s\": %m",
                        fname)));
        return -1;
    }

    /*
     * To guarantee that the removal of the file is persistent, fsync its
     * parent directory.
     */
    if (fsync_parent_path(fname, elevel) != 0)
        return -1;

    return 0;
}

FileAccess()

static int FileAccess ( File  file )

static

Definition at line 1275 of file fd.c.

References Delete(), DO_DB, elog, FileIsNotOpen, vfd::fileName, Insert(), LOG, LruInsert(), and vfd::lruLessRecently.

Referenced by FilePrefetch(), FileRead(), FileSize(), FileSync(), FileTruncate(), FileWrite(), and FileWriteback().

{
    int         returnValue;

    DO_DB(elog(LOG, "FileAccess %d (%s)",
               file, VfdCache[file].fileName));

    /*
     * Is the file open?  If not, open it and put it at the head of the LRU
     * ring (possibly closing the least recently used file to get an FD).
     */

    if (FileIsNotOpen(file))
    {
        returnValue = LruInsert(file);
        if (returnValue != 0)
            return returnValue;
    }
    else if (VfdCache[0].lruLessRecently != file)
    {
        /*
         * We now know that the file is open and that it is not the last one
         * accessed, so we need to move it to the head of the Lru ring.
         */

        Delete(file);
        Insert(file);
    }

    return 0;
}

FileClose()

void FileClose

(

File

file

)

Definition at line 1748 of file fd.c.

References Assert, close, data_sync_elevel(), Delete(), DO_DB, elog, vfd::fd, FD_DELETE_AT_CLOSE, FD_TEMP_FILE_LIMIT, vfd::fdstate, FileIsNotOpen, FileIsValid, vfd::fileName, vfd::fileSize, FreeVfd(), LOG, nfile, ReportTemporaryFileUsage(), ResourceOwnerForgetFile(), vfd::resowner, stat, temporary_files_size, and VFD_CLOSED.

Referenced by BufFileClose(), CleanupTempFiles(), logical_end_heap_rewrite(), mdclose(), mdsyncfiletag(), mdtruncate(), ReorderBufferIterTXNFinish(), ReorderBufferRestoreChanges(), and ResourceOwnerReleaseInternal().

{
    Vfd        *vfdP;

    Assert(FileIsValid(file));

    DO_DB(elog(LOG, "FileClose: %d (%s)",
               file, VfdCache[file].fileName));

    vfdP = &VfdCache[file];

    if (!FileIsNotOpen(file))
    {
        /* close the file */
        if (close(vfdP->fd) != 0)
        {
            /*
             * We may need to panic on failure to close non-temporary files;
             * see LruDelete.
             */
            elog(vfdP->fdstate & FD_TEMP_FILE_LIMIT ? LOG : data_sync_elevel(LOG),
                 "could not close file \"%s\": %m", vfdP->fileName);
        }

        --nfile;
        vfdP->fd = VFD_CLOSED;

        /* remove the file from the lru ring */
        Delete(file);
    }

    if (vfdP->fdstate & FD_TEMP_FILE_LIMIT)
    {
        /* Subtract its size from current usage (do first in case of error) */
        temporary_files_size -= vfdP->fileSize;
        vfdP->fileSize = 0;
    }

    /*
     * Delete the file if it was temporary, and make a log entry if wanted
     */
    if (vfdP->fdstate & FD_DELETE_AT_CLOSE)
    {
        struct stat filestats;
        int         stat_errno;

        /*
         * If we get an error, as could happen within the ereport/elog calls,
         * we'll come right back here during transaction abort.  Reset the
         * flag to ensure that we can't get into an infinite loop.  This code
         * is arranged to ensure that the worst-case consequence is failing to
         * emit log message(s), not failing to attempt the unlink.
         */
        vfdP->fdstate &= ~FD_DELETE_AT_CLOSE;


        /* first try the stat() */
        if (stat(vfdP->fileName, &filestats))
            stat_errno = errno;
        else
            stat_errno = 0;

        /* in any case do the unlink */
        if (unlink(vfdP->fileName))
            elog(LOG, "could not unlink file \"%s\": %m", vfdP->fileName);

        /* and last report the stat results */
        if (stat_errno == 0)
            ReportTemporaryFileUsage(vfdP->fileName, filestats.st_size);
        else
        {
            errno = stat_errno;
            elog(LOG, "could not stat file \"%s\": %m", vfdP->fileName);
        }
    }

    /* Unregister it from the resource owner */
    if (vfdP->resowner)
        ResourceOwnerForgetFile(vfdP->resowner, file);

    /*
     * Return the Vfd slot to the free list
     */
    FreeVfd(file);
}

FileGetRawDesc()

int FileGetRawDesc

(

File

file

)

Definition at line 2138 of file fd.c.

References Assert, vfd::fd, and FileIsValid.

{
    Assert(FileIsValid(file));
    return VfdCache[file].fd;
}

FileGetRawFlags()

int FileGetRawFlags

(

File

file

)

Definition at line 2148 of file fd.c.

References Assert, vfd::fileFlags, and FileIsValid.

{
    Assert(FileIsValid(file));
    return VfdCache[file].fileFlags;
}

FileGetRawMode()

mode_t FileGetRawMode

(

File

file

)

Definition at line 2158 of file fd.c.

References Assert, FileIsValid, and vfd::fileMode.

{
    Assert(FileIsValid(file));
    return VfdCache[file].fileMode;
}

FilePathName()

char* FilePathName

(

File

file

)

Definition at line 2122 of file fd.c.

References Assert, FileIsValid, and vfd::fileName.

Referenced by _mdnblocks(), BufFileSize(), mdextend(), mdimmedsync(), mdread(), mdsyncfiletag(), mdtruncate(), mdwrite(), and register_dirty_segment().

{
    Assert(FileIsValid(file));

    return VfdCache[file].fileName;
}

FilePrefetch()

int FilePrefetch	(	File	file,
		off_t	offset,
		int	amount,
		uint32	wait_event_info
	)

Definition at line 1844 of file fd.c.

References Assert, DO_DB, elog, vfd::fd, FileAccess(), FileIsValid, vfd::fileName, INT64_FORMAT, LOG, pgstat_report_wait_end(), and pgstat_report_wait_start().

Referenced by mdprefetch().

{
#if defined(USE_POSIX_FADVISE) && defined(POSIX_FADV_WILLNEED)
    int         returnCode;

    Assert(FileIsValid(file));

    DO_DB(elog(LOG, "FilePrefetch: %d (%s) " INT64_FORMAT " %d",
               file, VfdCache[file].fileName,
               (int64) offset, amount));

    returnCode = FileAccess(file);
    if (returnCode < 0)
        return returnCode;

    pgstat_report_wait_start(wait_event_info);
    returnCode = posix_fadvise(VfdCache[file].fd, offset, amount,
                               POSIX_FADV_WILLNEED);
    pgstat_report_wait_end();

    return returnCode;
#else
    Assert(FileIsValid(file));
    return 0;
#endif
}

FileRead()

int FileRead	(	File	file,
		char *	buffer,
		int	amount,
		off_t	offset,
		uint32	wait_event_info
	)

Definition at line 1895 of file fd.c.

References _dosmaperr(), Assert, DO_DB, EINTR, elog, error(), vfd::fd, FileAccess(), FileIsValid, vfd::fileName, INT64_FORMAT, LOG, pg_pread(), pg_usleep(), pgstat_report_wait_end(), and pgstat_report_wait_start().

Referenced by BufFileLoadBuffer(), mdread(), and ReorderBufferRestoreChanges().

{
    int         returnCode;
    Vfd        *vfdP;

    Assert(FileIsValid(file));

    DO_DB(elog(LOG, "FileRead: %d (%s) " INT64_FORMAT " %d %p",
               file, VfdCache[file].fileName,
               (int64) offset,
               amount, buffer));

    returnCode = FileAccess(file);
    if (returnCode < 0)
        return returnCode;

    vfdP = &VfdCache[file];

retry:
    pgstat_report_wait_start(wait_event_info);
    returnCode = pg_pread(vfdP->fd, buffer, amount, offset);
    pgstat_report_wait_end();

    if (returnCode < 0)
    {
        /*
         * Windows may run out of kernel buffers and return "Insufficient
         * system resources" error.  Wait a bit and retry to solve it.
         *
         * It is rumored that EINTR is also possible on some Unix filesystems,
         * in which case immediate retry is indicated.
         */
#ifdef WIN32
        DWORD       error = GetLastError();

        switch (error)
        {
            case ERROR_NO_SYSTEM_RESOURCES:
                pg_usleep(1000L);
                errno = EINTR;
                break;
            default:
                _dosmaperr(error);
                break;
        }
#endif
        /* OK to retry if interrupted */
        if (errno == EINTR)
            goto retry;
    }

    return returnCode;
}

FileSize()

off_t FileSize

(

File

file

)

Definition at line 2070 of file fd.c.

References Assert, DO_DB, elog, vfd::fd, FileAccess(), FileIsNotOpen, FileIsValid, vfd::fileName, and LOG.

Referenced by _mdnblocks(), and BufFileSize().

{
    Assert(FileIsValid(file));

    DO_DB(elog(LOG, "FileSize %d (%s)",
               file, VfdCache[file].fileName));

    if (FileIsNotOpen(file))
    {
        if (FileAccess(file) < 0)
            return (off_t) -1;
    }

    return lseek(VfdCache[file].fd, 0, SEEK_END);
}

FileSync()

int FileSync	(	File	file,
		uint32	wait_event_info
	)

Definition at line 2049 of file fd.c.

References Assert, DO_DB, elog, vfd::fd, FileAccess(), FileIsValid, vfd::fileName, LOG, pg_fsync(), pgstat_report_wait_end(), and pgstat_report_wait_start().

Referenced by logical_end_heap_rewrite(), mdimmedsync(), mdsyncfiletag(), and register_dirty_segment().

{
    int         returnCode;

    Assert(FileIsValid(file));

    DO_DB(elog(LOG, "FileSync: %d (%s)",
               file, VfdCache[file].fileName));

    returnCode = FileAccess(file);
    if (returnCode < 0)
        return returnCode;

    pgstat_report_wait_start(wait_event_info);
    returnCode = pg_fsync(VfdCache[file].fd);
    pgstat_report_wait_end();

    return returnCode;
}

FileTruncate()

int FileTruncate	(	File	file,
		off_t	offset,
		uint32	wait_event_info
	)

Definition at line 2087 of file fd.c.

References Assert, DO_DB, elog, vfd::fd, FD_TEMP_FILE_LIMIT, vfd::fdstate, FileAccess(), FileIsValid, vfd::fileName, vfd::fileSize, ftruncate, LOG, pgstat_report_wait_end(), pgstat_report_wait_start(), and temporary_files_size.

Referenced by mdtruncate().

{
    int         returnCode;

    Assert(FileIsValid(file));

    DO_DB(elog(LOG, "FileTruncate %d (%s)",
               file, VfdCache[file].fileName));

    returnCode = FileAccess(file);
    if (returnCode < 0)
        return returnCode;

    pgstat_report_wait_start(wait_event_info);
    returnCode = ftruncate(VfdCache[file].fd, offset);
    pgstat_report_wait_end();

    if (returnCode == 0 && VfdCache[file].fileSize > offset)
    {
        /* adjust our state for truncation of a temp file */
        Assert(VfdCache[file].fdstate & FD_TEMP_FILE_LIMIT);
        temporary_files_size -= VfdCache[file].fileSize - offset;
        VfdCache[file].fileSize = offset;
    }

    return returnCode;
}

FileWrite()

int FileWrite	(	File	file,
		char *	buffer,
		int	amount,
		off_t	offset,
		uint32	wait_event_info
	)

Definition at line 1951 of file fd.c.

References _dosmaperr(), Assert, DO_DB, EINTR, elog, ereport, errcode(), errmsg(), ERROR, error(), vfd::fd, FD_TEMP_FILE_LIMIT, vfd::fdstate, FileAccess(), FileIsValid, vfd::fileName, vfd::fileSize, INT64_FORMAT, LOG, pg_pwrite(), pg_usleep(), pgstat_report_wait_end(), pgstat_report_wait_start(), temp_file_limit, and temporary_files_size.

Referenced by BufFileDumpBuffer(), logical_heap_rewrite_flush_mappings(), mdextend(), and mdwrite().

{
    int         returnCode;
    Vfd        *vfdP;

    Assert(FileIsValid(file));

    DO_DB(elog(LOG, "FileWrite: %d (%s) " INT64_FORMAT " %d %p",
               file, VfdCache[file].fileName,
               (int64) offset,
               amount, buffer));

    returnCode = FileAccess(file);
    if (returnCode < 0)
        return returnCode;

    vfdP = &VfdCache[file];

    /*
     * If enforcing temp_file_limit and it's a temp file, check to see if the
     * write would overrun temp_file_limit, and throw error if so.  Note: it's
     * really a modularity violation to throw error here; we should set errno
     * and return -1.  However, there's no way to report a suitable error
     * message if we do that.  All current callers would just throw error
     * immediately anyway, so this is safe at present.
     */
    if (temp_file_limit >= 0 && (vfdP->fdstate & FD_TEMP_FILE_LIMIT))
    {
        off_t       past_write = offset + amount;

        if (past_write > vfdP->fileSize)
        {
            uint64      newTotal = temporary_files_size;

            newTotal += past_write - vfdP->fileSize;
            if (newTotal > (uint64) temp_file_limit * (uint64) 1024)
                ereport(ERROR,
                        (errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
                         errmsg("temporary file size exceeds temp_file_limit (%dkB)",
                                temp_file_limit)));
        }
    }

retry:
    errno = 0;
    pgstat_report_wait_start(wait_event_info);
    returnCode = pg_pwrite(VfdCache[file].fd, buffer, amount, offset);
    pgstat_report_wait_end();

    /* if write didn't set errno, assume problem is no disk space */
    if (returnCode != amount && errno == 0)
        errno = ENOSPC;

    if (returnCode >= 0)
    {
        /*
         * Maintain fileSize and temporary_files_size if it's a temp file.
         */
        if (vfdP->fdstate & FD_TEMP_FILE_LIMIT)
        {
            off_t       past_write = offset + amount;

            if (past_write > vfdP->fileSize)
            {
                temporary_files_size += past_write - vfdP->fileSize;
                vfdP->fileSize = past_write;
            }
        }
    }
    else
    {
        /*
         * See comments in FileRead()
         */
#ifdef WIN32
        DWORD       error = GetLastError();

        switch (error)
        {
            case ERROR_NO_SYSTEM_RESOURCES:
                pg_usleep(1000L);
                errno = EINTR;
                break;
            default:
                _dosmaperr(error);
                break;
        }
#endif
        /* OK to retry if interrupted */
        if (errno == EINTR)
            goto retry;
    }

    return returnCode;
}

FileWriteback()

void FileWriteback	(	File	file,
		off_t	offset,
		off_t	nbytes,
		uint32	wait_event_info
	)

Definition at line 1872 of file fd.c.

References Assert, DO_DB, elog, vfd::fd, FileAccess(), FileIsValid, vfd::fileName, INT64_FORMAT, LOG, pg_flush_data(), pgstat_report_wait_end(), and pgstat_report_wait_start().

Referenced by mdwriteback().

{
    int         returnCode;

    Assert(FileIsValid(file));

    DO_DB(elog(LOG, "FileWriteback: %d (%s) " INT64_FORMAT " " INT64_FORMAT,
               file, VfdCache[file].fileName,
               (int64) offset, (int64) nbytes));

    if (nbytes <= 0)
        return;

    returnCode = FileAccess(file);
    if (returnCode < 0)
        return;

    pgstat_report_wait_start(wait_event_info);
    pg_flush_data(VfdCache[file].fd, offset, nbytes);
    pgstat_report_wait_end();
}

FreeDesc()

static int FreeDesc ( AllocateDesc *  desc )

static

Definition at line 2402 of file fd.c.

References AllocateDescDir, AllocateDescFile, AllocateDescPipe, AllocateDescRawFD, close, closedir(), AllocateDesc::desc, AllocateDesc::dir, elog, ERROR, AllocateDesc::fd, AllocateDesc::file, AllocateDesc::kind, and numAllocatedDescs.

Referenced by AtEOSubXact_Files(), CleanupTempFiles(), ClosePipeStream(), CloseTransientFile(), FreeDir(), and FreeFile().

{
    int         result;

    /* Close the underlying object */
    switch (desc->kind)
    {
        case AllocateDescFile:
            result = fclose(desc->desc.file);
            break;
        case AllocateDescPipe:
            result = pclose(desc->desc.file);
            break;
        case AllocateDescDir:
            result = closedir(desc->desc.dir);
            break;
        case AllocateDescRawFD:
            result = close(desc->desc.fd);
            break;
        default:
            elog(ERROR, "AllocateDesc kind not recognized");
            result = 0;         /* keep compiler quiet */
            break;
    }

    /* Compact storage in the allocatedDescs array */
    numAllocatedDescs--;
    *desc = allocatedDescs[numAllocatedDescs];

    return result;
}

FreeDir()

int FreeDir

(

DIR *

dir

)

Definition at line 2621 of file fd.c.

References AllocateDescDir, closedir(), AllocateDesc::desc, AllocateDesc::dir, DO_DB, elog, FreeDesc(), i, AllocateDesc::kind, LOG, numAllocatedDescs, and WARNING.

Referenced by calculate_database_size(), calculate_tablespace_size(), CheckPointLogicalRewriteHeap(), CheckPointSnapBuild(), CleanupBackupHistory(), copydir(), db_dir_size(), DeleteAllExportedSnapshotFiles(), destroy_tablespace_directories(), directory_is_empty(), do_pg_start_backup(), dsm_cleanup_for_mmap(), get_ext_ver_list(), getInstallationPaths(), movedb(), ParseTzFile(), perform_base_backup(), pg_available_extension_versions(), pg_available_extensions(), pg_logdir_ls_internal(), pg_ls_dir(), pg_ls_dir_files(), pg_tablespace_databases(), pg_tzenumerate_end(), pg_tzenumerate_next(), pgarch_readyXlog(), pgstat_reset_remove_files(), RelationCacheInitFileRemove(), RelationCacheInitFileRemoveInDir(), RemoveNonParentXlogFiles(), RemoveOldXlogFiles(), RemovePgTempFiles(), RemovePgTempFilesInDir(), RemovePgTempRelationFiles(), RemovePgTempRelationFilesInDbspace(), RemoveTempXlogFiles(), ReorderBufferCleanupSerializedTXNs(), ResetUnloggedRelations(), ResetUnloggedRelationsInDbspaceDir(), ResetUnloggedRelationsInTablespaceDir(), restoreTwoPhaseData(), scan_directory_ci(), sendDir(), SlruScanDirectory(), StartupReorderBuffer(), StartupReplicationSlots(), UpdateLogicalMappings(), and walkdir().

{
    int         i;

    /* Nothing to do if AllocateDir failed */
    if (dir == NULL)
        return 0;

    DO_DB(elog(LOG, "FreeDir: Allocated %d", numAllocatedDescs));

    /* Remove dir from list of allocated dirs, if it's present */
    for (i = numAllocatedDescs; --i >= 0;)
    {
        AllocateDesc *desc = &allocatedDescs[i];

        if (desc->kind == AllocateDescDir && desc->desc.dir == dir)
            return FreeDesc(desc);
    }

    /* Only get here if someone passes us a dir not in allocatedDescs */
    elog(WARNING, "dir passed to FreeDir was not obtained from AllocateDir");

    return closedir(dir);
}

FreeFile()

int FreeFile

(

FILE *

file

)

Definition at line 2441 of file fd.c.

References AllocateDescFile, AllocateDesc::desc, DO_DB, elog, AllocateDesc::file, FreeDesc(), i, AllocateDesc::kind, LOG, numAllocatedDescs, and WARNING.

Referenced by _ShowOption(), AlterSystemSetConfigFile(), apw_dump_now(), apw_load_buffers(), BackendRun(), checkControlFile(), do_pg_start_backup(), do_pg_stop_backup(), EndCopy(), entry_reset(), existsTimeLineHistory(), ExportSnapshot(), fill_hba_view(), gc_qtexts(), ImportSnapshot(), load_dh_file(), load_hba(), load_ident(), load_relcache_init_file(), parse_extension_control_file(), ParseTzFile(), perform_base_backup(), pg_backup_start_time(), pg_current_logfile(), pg_file_write_internal(), pg_promote(), PGSharedMemoryAttach(), pgss_shmem_shutdown(), pgss_shmem_startup(), pgstat_read_db_statsfile(), pgstat_read_db_statsfile_timestamp(), pgstat_read_statsfiles(), pgstat_write_db_statsfile(), pgstat_write_statsfiles(), PostmasterMarkPIDForWorkerNotify(), read_backup_label(), read_binary_file(), read_tablespace_map(), read_whole_file(), readTimeLineHistory(), sendFile(), tokenize_inc_file(), tsearch_readline_end(), ValidatePgVersion(), write_relcache_init_file(), XLogArchiveForceDone(), and XLogArchiveNotify().

{
    int         i;

    DO_DB(elog(LOG, "FreeFile: Allocated %d", numAllocatedDescs));

    /* Remove file from list of allocated files, if it's present */
    for (i = numAllocatedDescs; --i >= 0;)
    {
        AllocateDesc *desc = &allocatedDescs[i];

        if (desc->kind == AllocateDescFile && desc->desc.file == file)
            return FreeDesc(desc);
    }

    /* Only get here if someone passes us a file not in allocatedDescs */
    elog(WARNING, "file passed to FreeFile was not obtained from AllocateFile");

    return fclose(file);
}

FreeVfd()

static void FreeVfd ( File  file )

static

Definition at line 1255 of file fd.c.

References DO_DB, elog, vfd::fdstate, vfd::fileName, free, LOG, and vfd::nextFree.

Referenced by FileClose(), and PathNameOpenFilePerm().

{
    Vfd        *vfdP = &VfdCache[file];

    DO_DB(elog(LOG, "FreeVfd: %d (%s)",
               file, vfdP->fileName ? vfdP->fileName : ""));

    if (vfdP->fileName != NULL)
    {
        free(vfdP->fileName);
        vfdP->fileName = NULL;
    }
    vfdP->fdstate = 0x0;

    vfdP->nextFree = VfdCache[0].nextFree;
    VfdCache[0].nextFree = file;
}

fsync_fname()

void fsync_fname	(	const char *	fname,
		bool	isdir
	)

Definition at line 617 of file fd.c.

Referenced by _CloseArchive(), CheckPointCLOG(), CheckPointCommitTs(), CheckPointTwoPhase(), copydir(), CreateSlotOnDisk(), dir_close(), dir_finish(), dir_open_for_write(), main(), ReplicationSlotDropPtr(), ResetUnloggedRelationsInDbspaceDir(), RestoreSlotFromDisk(), SaveSlotToPath(), ShutdownCLOG(), ShutdownCommitTs(), SnapBuildRestore(), SnapBuildSerialize(), StartupReplicationSlots(), and tar_finish().

{
    fsync_fname_ext(fname, isdir, false, data_sync_elevel(ERROR));
}

fsync_fname_ext()

static int fsync_fname_ext ( const char *  fname, bool  isdir, bool  ignore_perm, int  elevel  )

static

Definition at line 3380 of file fd.c.

References CloseTransientFile(), ereport, errcode_for_file_access(), errmsg(), vfd::fd, OpenTransientFile(), PG_BINARY, and pg_fsync().

Referenced by datadir_fsync_fname(), durable_link_or_rename(), durable_rename(), fsync_fname(), and fsync_parent_path().

{
    int         fd;
    int         flags;
    int         returncode;

    /*
     * Some OSs require directories to be opened read-only whereas other
     * systems don't allow us to fsync files opened read-only; so we need both
     * cases here.  Using O_RDWR will cause us to fail to fsync files that are
     * not writable by our userid, but we assume that's OK.
     */
    flags = PG_BINARY;
    if (!isdir)
        flags |= O_RDWR;
    else
        flags |= O_RDONLY;

    fd = OpenTransientFile(fname, flags);

    /*
     * Some OSs don't allow us to open directories at all (Windows returns
     * EACCES), just ignore the error in that case.  If desired also silently
     * ignoring errors about unreadable files. Log others.
     */
    if (fd < 0 && isdir && (errno == EISDIR || errno == EACCES))
        return 0;
    else if (fd < 0 && ignore_perm && errno == EACCES)
        return 0;
    else if (fd < 0)
    {
        ereport(elevel,
                (errcode_for_file_access(),
                 errmsg("could not open file \"%s\": %m", fname)));
        return -1;
    }

    returncode = pg_fsync(fd);

    /*
     * Some OSes don't allow us to fsync directories at all, so we can ignore
     * those errors. Anything else needs to be logged.
     */
    if (returncode != 0 && !(isdir && (errno == EBADF || errno == EINVAL)))
    {
        int         save_errno;

        /* close file upon error, might not be in transaction context */
        save_errno = errno;
        (void) CloseTransientFile(fd);
        errno = save_errno;

        ereport(elevel,
                (errcode_for_file_access(),
                 errmsg("could not fsync file \"%s\": %m", fname)));
        return -1;
    }

    if (CloseTransientFile(fd) != 0)
    {
        ereport(elevel,
                (errcode_for_file_access(),
                 errmsg("could not close file \"%s\": %m", fname)));
        return -1;
    }

    return 0;
}

fsync_parent_path()

static int fsync_parent_path ( const char *  fname, int  elevel  )

static

Definition at line 3456 of file fd.c.

References fsync_fname_ext(), get_parent_directory(), MAXPGPATH, and strlcpy().

Referenced by dir_close(), dir_open_for_write(), durable_link_or_rename(), durable_rename(), durable_unlink(), and tar_finish().

{
    char        parentpath[MAXPGPATH];

    strlcpy(parentpath, fname, MAXPGPATH);
    get_parent_directory(parentpath);

    /*
     * get_parent_directory() returns an empty string if the input argument is
     * just a file name (see comments in path.c), so handle that as being the
     * current directory.
     */
    if (strlen(parentpath) == 0)
        strlcpy(parentpath, ".", MAXPGPATH);

    if (fsync_fname_ext(parentpath, true, false, elevel) != 0)
        return -1;

    return 0;
}

GetNextTempTableSpace()

Oid GetNextTempTableSpace

(

void

)

Definition at line 2764 of file fd.c.

References InvalidOid, nextTempTableSpace, numTempTableSpaces, and tempTableSpaces.

Referenced by GetDefaultTablespace(), and OpenTemporaryFile().

{
    if (numTempTableSpaces > 0)
    {
        /* Advance nextTempTableSpace counter with wraparound */
        if (++nextTempTableSpace >= numTempTableSpaces)
            nextTempTableSpace = 0;
        return tempTableSpaces[nextTempTableSpace];
    }
    return InvalidOid;
}

GetTempTablespaces()

int GetTempTablespaces	(	Oid *	tableSpaces,
		int	numSpaces
	)

Definition at line 2746 of file fd.c.

References Assert, i, numTempTableSpaces, tempTableSpaces, and TempTablespacesAreSet().

Referenced by SharedFileSetInit().

{
    int         i;

    Assert(TempTablespacesAreSet());
    for (i = 0; i < numTempTableSpaces && i < numSpaces; ++i)
        tableSpaces[i] = tempTableSpaces[i];

    return i;
}

InitFileAccess()

void InitFileAccess

(

void

)

Definition at line 821 of file fd.c.

References Assert, AtProcExit_Files(), ereport, errcode(), errmsg(), FATAL, vfd::fd, malloc, MemSet, on_proc_exit(), SizeVfdCache, and VFD_CLOSED.

Referenced by BaseInit().

{
    Assert(SizeVfdCache == 0);  /* call me only once */

    /* initialize cache header entry */
    VfdCache = (Vfd *) malloc(sizeof(Vfd));
    if (VfdCache == NULL)
        ereport(FATAL,
                (errcode(ERRCODE_OUT_OF_MEMORY),
                 errmsg("out of memory")));

    MemSet((char *) &(VfdCache[0]), 0, sizeof(Vfd));
    VfdCache->fd = VFD_CLOSED;

    SizeVfdCache = 1;

    /* register proc-exit hook to ensure temp files are dropped at exit */
    on_proc_exit(AtProcExit_Files, 0);
}

Insert()

static void Insert ( File  file )

static

Definition at line 1096 of file fd.c.

References Assert, DO_DB, elog, vfd::fileName, LOG, vfd::lruLessRecently, and vfd::lruMoreRecently.

Referenced by AdvanceXLInsertBuffer(), CreateCheckPoint(), FileAccess(), GetXLogInsertRecPtr(), InitXLOGAccess(), LruInsert(), PathNameOpenFilePerm(), ReserveXLogInsertLocation(), ReserveXLogSwitch(), StartupXLOG(), UpdateFullPageWrites(), WaitXLogInsertionsToFinish(), and XLogInsertRecord().

{
    Vfd        *vfdP;

    Assert(file != 0);

    DO_DB(elog(LOG, "Insert %d (%s)",
               file, VfdCache[file].fileName));
    DO_DB(_dump_lru());

    vfdP = &VfdCache[file];

    vfdP->lruMoreRecently = 0;
    vfdP->lruLessRecently = VfdCache[0].lruLessRecently;
    VfdCache[0].lruLessRecently = file;
    VfdCache[vfdP->lruLessRecently].lruMoreRecently = file;

    DO_DB(_dump_lru());
}

looks_like_temp_rel_name()

bool looks_like_temp_rel_name

(

const char *

name

)

Definition at line 3101 of file fd.c.

References forkname_chars().

Referenced by RemovePgTempRelationFilesInDbspace(), and sendDir().

{
    int         pos;
    int         savepos;

    /* Must start with "t". */
    if (name[0] != 't')
        return false;

    /* Followed by a non-empty string of digits and then an underscore. */
    for (pos = 1; isdigit((unsigned char) name[pos]); ++pos)
        ;
    if (pos == 1 || name[pos] != '_')
        return false;

    /* Followed by another nonempty string of digits. */
    for (savepos = ++pos; isdigit((unsigned char) name[pos]); ++pos)
        ;
    if (savepos == pos)
        return false;

    /* We might have _forkname or .segment or both. */
    if (name[pos] == '_')
    {
        int         forkchar = forkname_chars(&name[pos + 1], NULL);

        if (forkchar <= 0)
            return false;
        pos += forkchar + 1;
    }
    if (name[pos] == '.')
    {
        int         segchar;

        for (segchar = 1; isdigit((unsigned char) name[pos + segchar]); ++segchar)
            ;
        if (segchar <= 1)
            return false;
        pos += segchar;
    }

    /* Now we should be at the end. */
    if (name[pos] != '\0')
        return false;
    return true;
}

LruDelete()

static void LruDelete ( File  file )

static

Definition at line 1070 of file fd.c.

References Assert, close, data_sync_elevel(), Delete(), DO_DB, elog, vfd::fd, FD_TEMP_FILE_LIMIT, vfd::fdstate, vfd::fileName, LOG, nfile, and VFD_CLOSED.

Referenced by closeAllVfds(), RegisterTemporaryFile(), and ReleaseLruFile().

{
    Vfd        *vfdP;

    Assert(file != 0);

    DO_DB(elog(LOG, "LruDelete %d (%s)",
               file, VfdCache[file].fileName));

    vfdP = &VfdCache[file];

    /*
     * Close the file.  We aren't expecting this to fail; if it does, better
     * to leak the FD than to mess up our internal state.
     */
    if (close(vfdP->fd) != 0)
        elog(vfdP->fdstate & FD_TEMP_FILE_LIMIT ? LOG : data_sync_elevel(LOG),
             "could not close file \"%s\": %m", vfdP->fileName);
    vfdP->fd = VFD_CLOSED;
    --nfile;

    /* delete the vfd record from the LRU ring */
    Delete(file);
}

LruInsert()

static int LruInsert ( File  file )

static

Definition at line 1118 of file fd.c.

References Assert, BasicOpenFilePerm(), DO_DB, elog, vfd::fd, vfd::fileFlags, FileIsNotOpen, vfd::fileMode, vfd::fileName, Insert(), LOG, nfile, and ReleaseLruFiles().

Referenced by FileAccess().

{
    Vfd        *vfdP;

    Assert(file != 0);

    DO_DB(elog(LOG, "LruInsert %d (%s)",
               file, VfdCache[file].fileName));

    vfdP = &VfdCache[file];

    if (FileIsNotOpen(file))
    {
        /* Close excess kernel FDs. */
        ReleaseLruFiles();

        /*
         * The open could still fail for lack of file descriptors, eg due to
         * overall system file table being full.  So, be prepared to release
         * another FD if necessary...
         */
        vfdP->fd = BasicOpenFilePerm(vfdP->fileName, vfdP->fileFlags,
                                     vfdP->fileMode);
        if (vfdP->fd < 0)
        {
            DO_DB(elog(LOG, "re-open failed: %m"));
            return -1;
        }
        else
        {
            ++nfile;
        }
    }

    /*
     * put it at the head of the Lru ring
     */

    Insert(file);

    return 0;
}

MakePGDirectory()

int MakePGDirectory

(

const char *

directoryName

)

Definition at line 3496 of file fd.c.

References mkdir, and pg_dir_create_mode.

Referenced by BackendRun(), copydir(), create_tablespace_directories(), CreateSlotOnDisk(), OpenTemporaryFileInTablespace(), PathNameCreateTemporaryDir(), SysLogger_Start(), SysLoggerMain(), TablespaceCreateDbspace(), and ValidateXLOGDirectoryStructure().

{
    return mkdir(directoryName, pg_dir_create_mode);
}

OpenPipeStream()

FILE* OpenPipeStream	(	const char *	command,
		const char *	mode
	)

Definition at line 2345 of file fd.c.

References AllocateDescPipe, AllocateDesc::create_subid, AllocateDesc::desc, DO_DB, elog, ereport, errcode(), errmsg(), ERROR, AllocateDesc::file, GetCurrentSubTransactionId(), AllocateDesc::kind, LOG, maxAllocatedDescs, numAllocatedDescs, pqsignal(), ReleaseLruFile(), ReleaseLruFiles(), reserveAllocatedDesc(), SIG_DFL, SIG_IGN, SIGPIPE, and generate_unaccent_rules::stdout.

Referenced by BeginCopyFrom(), BeginCopyTo(), pg_import_system_collations(), and run_ssl_passphrase_command().

{
    FILE       *file;
    int         save_errno;

    DO_DB(elog(LOG, "OpenPipeStream: Allocated %d (%s)",
               numAllocatedDescs, command));

    /* Can we allocate another non-virtual FD? */
    if (!reserveAllocatedDesc())
        ereport(ERROR,
                (errcode(ERRCODE_INSUFFICIENT_RESOURCES),
                 errmsg("exceeded maxAllocatedDescs (%d) while trying to execute command \"%s\"",
                        maxAllocatedDescs, command)));

    /* Close excess kernel FDs. */
    ReleaseLruFiles();

TryAgain:
    fflush(stdout);
    fflush(stderr);
    pqsignal(SIGPIPE, SIG_DFL);
    errno = 0;
    file = popen(command, mode);
    save_errno = errno;
    pqsignal(SIGPIPE, SIG_IGN);
    errno = save_errno;
    if (file != NULL)
    {
        AllocateDesc *desc = &allocatedDescs[numAllocatedDescs];

        desc->kind = AllocateDescPipe;
        desc->desc.file = file;
        desc->create_subid = GetCurrentSubTransactionId();
        numAllocatedDescs++;
        return desc->desc.file;
    }

    if (errno == EMFILE || errno == ENFILE)
    {
        ereport(LOG,
                (errcode(ERRCODE_INSUFFICIENT_RESOURCES),
                 errmsg("out of file descriptors: %m; release and retry")));
        if (ReleaseLruFile())
            goto TryAgain;
        errno = save_errno;
    }

    return NULL;
}

OpenTemporaryFile()

File OpenTemporaryFile

(

bool

interXact

)

Definition at line 1499 of file fd.c.

References CurrentResourceOwner, FD_DELETE_AT_CLOSE, FD_TEMP_FILE_LIMIT, vfd::fdstate, GetNextTempTableSpace(), MyDatabaseTableSpace, numTempTableSpaces, OidIsValid, OpenTemporaryFileInTablespace(), RegisterTemporaryFile(), and ResourceOwnerEnlargeFiles().

Referenced by BufFileCreateTemp(), and extendBufFile().

{
    File        file = 0;

    /*
     * Make sure the current resource owner has space for this File before we
     * open it, if we'll be registering it below.
     */
    if (!interXact)
        ResourceOwnerEnlargeFiles(CurrentResourceOwner);

    /*
     * If some temp tablespace(s) have been given to us, try to use the next
     * one.  If a given tablespace can't be found, we silently fall back to
     * the database's default tablespace.
     *
     * BUT: if the temp file is slated to outlive the current transaction,
     * force it into the database's default tablespace, so that it will not
     * pose a threat to possible tablespace drop attempts.
     */
    if (numTempTableSpaces > 0 && !interXact)
    {
        Oid         tblspcOid = GetNextTempTableSpace();

        if (OidIsValid(tblspcOid))
            file = OpenTemporaryFileInTablespace(tblspcOid, false);
    }

    /*
     * If not, or if tablespace is bad, create in database's default
     * tablespace.  MyDatabaseTableSpace should normally be set before we get
     * here, but just in case it isn't, fall back to pg_default tablespace.
     */
    if (file <= 0)
        file = OpenTemporaryFileInTablespace(MyDatabaseTableSpace ?
                                             MyDatabaseTableSpace :
                                             DEFAULTTABLESPACE_OID,
                                             true);

    /* Mark it for deletion at close and temporary file size limit */
    VfdCache[file].fdstate |= FD_DELETE_AT_CLOSE | FD_TEMP_FILE_LIMIT;

    /* Register it with the current resource owner */
    if (!interXact)
        RegisterTemporaryFile(file);

    return file;
}

OpenTemporaryFileInTablespace()

static File OpenTemporaryFileInTablespace ( Oid  tblspcOid, bool  rejectError  )

static

Definition at line 1577 of file fd.c.

References elog, ERROR, MakePGDirectory(), MAXPGPATH, MyProcPid, PathNameOpenFile(), PG_BINARY, PG_TEMP_FILE_PREFIX, snprintf, tempFileCounter, and TempTablespacePath().

Referenced by OpenTemporaryFile().

{
    char        tempdirpath[MAXPGPATH];
    char        tempfilepath[MAXPGPATH];
    File        file;

    TempTablespacePath(tempdirpath, tblspcOid);

    /*
     * Generate a tempfile name that should be unique within the current
     * database instance.
     */
    snprintf(tempfilepath, sizeof(tempfilepath), "%s/%s%d.%ld",
             tempdirpath, PG_TEMP_FILE_PREFIX, MyProcPid, tempFileCounter++);

    /*
     * Open the file.  Note: we don't use O_EXCL, in case there is an orphaned
     * temp file that can be reused.
     */
    file = PathNameOpenFile(tempfilepath,
                            O_RDWR | O_CREAT | O_TRUNC | PG_BINARY);
    if (file <= 0)
    {
        /*
         * We might need to create the tablespace's tempfile directory, if no
         * one has yet done so.
         *
         * Don't check for an error from MakePGDirectory; it could fail if
         * someone else just did the same thing.  If it doesn't work then
         * we'll bomb out on the second create attempt, instead.
         */
        (void) MakePGDirectory(tempdirpath);

        file = PathNameOpenFile(tempfilepath,
                                O_RDWR | O_CREAT | O_TRUNC | PG_BINARY);
        if (file <= 0 && rejectError)
            elog(ERROR, "could not create temporary file \"%s\": %m",
                 tempfilepath);
    }

    return file;
}

OpenTransientFile()

int OpenTransientFile	(	const char *	fileName,
		int	fileFlags
	)

Definition at line 2292 of file fd.c.

References OpenTransientFilePerm(), and pg_file_create_mode.

Referenced by ApplyLogicalMappingFile(), CheckPointLogicalRewriteHeap(), CheckPointReplicationOrigin(), copy_file(), dsm_impl_mmap(), durable_rename(), fsync_fname_ext(), get_controlfile(), heap_xlog_logical_rewrite(), lo_import_internal(), load_relmap_file(), mdunlinkfork(), qtext_load_file(), qtext_store(), ReadTwoPhaseFile(), RecreateTwoPhaseFile(), ReorderBufferSerializeTXN(), RestoreSlotFromDisk(), SaveSlotToPath(), SendTimeLineHistory(), SimpleLruDoesPhysicalPageExist(), SlruPhysicalReadPage(), SlruPhysicalWritePage(), SnapBuildRestore(), SnapBuildSerialize(), StartupReplicationOrigin(), walkdir(), write_relmap_file(), writeTimeLineHistory(), writeTimeLineHistoryFile(), and XLogFileCopy().

{
    return OpenTransientFilePerm(fileName, fileFlags, pg_file_create_mode);
}

OpenTransientFilePerm()

int OpenTransientFilePerm	(	const char *	fileName,
		int	fileFlags,
		mode_t	fileMode
	)

Definition at line 2301 of file fd.c.

References AllocateDescRawFD, BasicOpenFilePerm(), AllocateDesc::create_subid, AllocateDesc::desc, DO_DB, elog, ereport, errcode(), errmsg(), ERROR, vfd::fd, AllocateDesc::fd, GetCurrentSubTransactionId(), AllocateDesc::kind, LOG, maxAllocatedDescs, numAllocatedDescs, ReleaseLruFiles(), and reserveAllocatedDesc().

Referenced by be_lo_export(), and OpenTransientFile().

{
    int         fd;

    DO_DB(elog(LOG, "OpenTransientFile: Allocated %d (%s)",
               numAllocatedDescs, fileName));

    /* Can we allocate another non-virtual FD? */
    if (!reserveAllocatedDesc())
        ereport(ERROR,
                (errcode(ERRCODE_INSUFFICIENT_RESOURCES),
                 errmsg("exceeded maxAllocatedDescs (%d) while trying to open file \"%s\"",
                        maxAllocatedDescs, fileName)));

    /* Close excess kernel FDs. */
    ReleaseLruFiles();

    fd = BasicOpenFilePerm(fileName, fileFlags, fileMode);

    if (fd >= 0)
    {
        AllocateDesc *desc = &allocatedDescs[numAllocatedDescs];

        desc->kind = AllocateDescRawFD;
        desc->desc.fd = fd;
        desc->create_subid = GetCurrentSubTransactionId();
        numAllocatedDescs++;

        return fd;
    }

    return -1;                  /* failure */
}

PathNameCreateTemporaryDir()

void PathNameCreateTemporaryDir	(	const char *	basedir,
		const char *	directory
	)

Definition at line 1435 of file fd.c.

References ereport, errcode_for_file_access(), errmsg(), ERROR, and MakePGDirectory().

Referenced by SharedFileSetCreate().

{
    if (MakePGDirectory(directory) < 0)
    {
        if (errno == EEXIST)
            return;

        /*
         * Failed.  Try to create basedir first in case it's missing. Tolerate
         * EEXIST to close a race against another process following the same
         * algorithm.
         */
        if (MakePGDirectory(basedir) < 0 && errno != EEXIST)
            ereport(ERROR,
                    (errcode_for_file_access(),
                     errmsg("cannot create temporary directory \"%s\": %m",
                            basedir)));

        /* Try again. */
        if (MakePGDirectory(directory) < 0 && errno != EEXIST)
            ereport(ERROR,
                    (errcode_for_file_access(),
                     errmsg("cannot create temporary subdirectory \"%s\": %m",
                            directory)));
    }
}

PathNameCreateTemporaryFile()

File PathNameCreateTemporaryFile	(	const char *	path,
		bool	error_on_failure
	)

Definition at line 1634 of file fd.c.

References CurrentResourceOwner, ereport, errcode_for_file_access(), errmsg(), ERROR, FD_TEMP_FILE_LIMIT, vfd::fdstate, PathNameOpenFile(), PG_BINARY, RegisterTemporaryFile(), and ResourceOwnerEnlargeFiles().

Referenced by SharedFileSetCreate().

{
    File        file;

    ResourceOwnerEnlargeFiles(CurrentResourceOwner);

    /*
     * Open the file.  Note: we don't use O_EXCL, in case there is an orphaned
     * temp file that can be reused.
     */
    file = PathNameOpenFile(path, O_RDWR | O_CREAT | O_TRUNC | PG_BINARY);
    if (file <= 0)
    {
        if (error_on_failure)
            ereport(ERROR,
                    (errcode_for_file_access(),
                     errmsg("could not create temporary file \"%s\": %m",
                            path)));
        else
            return file;
    }

    /* Mark it for temp_file_limit accounting. */
    VfdCache[file].fdstate |= FD_TEMP_FILE_LIMIT;

    /* Register it for automatic close. */
    RegisterTemporaryFile(file);

    return file;
}

PathNameDeleteTemporaryDir()

void PathNameDeleteTemporaryDir

(

const char *

dirname

)

Definition at line 1466 of file fd.c.

References LOG, stat, unlink_if_exists_fname(), and walkdir().

Referenced by SharedFileSetDeleteAll().

{
    struct stat statbuf;

    /* Silently ignore missing directory. */
    if (stat(dirname, &statbuf) != 0 && errno == ENOENT)
        return;

    /*
     * Currently, walkdir doesn't offer a way for our passed in function to
     * maintain state.  Perhaps it should, so that we could tell the caller
     * whether this operation succeeded or failed.  Since this operation is
     * used in a cleanup path, we wouldn't actually behave differently: we'll
     * just log failures.
     */
    walkdir(dirname, unlink_if_exists_fname, false, LOG);
}

PathNameDeleteTemporaryFile()

bool PathNameDeleteTemporaryFile	(	const char *	path,
		bool	error_on_failure
	)

Definition at line 1702 of file fd.c.

References ereport, errcode_for_file_access(), errmsg(), ERROR, LOG, ReportTemporaryFileUsage(), and stat.

Referenced by SharedFileSetDelete(), and unlink_if_exists_fname().

{
    struct stat filestats;
    int         stat_errno;

    /* Get the final size for pgstat reporting. */
    if (stat(path, &filestats) != 0)
        stat_errno = errno;
    else
        stat_errno = 0;

    /*
     * Unlike FileClose's automatic file deletion code, we tolerate
     * non-existence to support BufFileDeleteShared which doesn't know how
     * many segments it has to delete until it runs out.
     */
    if (stat_errno == ENOENT)
        return false;

    if (unlink(path) < 0)
    {
        if (errno != ENOENT)
            ereport(error_on_failure ? ERROR : LOG,
                    (errcode_for_file_access(),
                     errmsg("could not unlink temporary file \"%s\": %m",
                            path)));
        return false;
    }

    if (stat_errno == 0)
        ReportTemporaryFileUsage(path, filestats.st_size);
    else
    {
        errno = stat_errno;
        ereport(LOG,
                (errcode_for_file_access(),
                 errmsg("could not stat file \"%s\": %m", path)));
    }

    return true;
}

PathNameOpenFile()

File PathNameOpenFile	(	const char *	fileName,
		int	fileFlags
	)

Definition at line 1358 of file fd.c.

References PathNameOpenFilePerm(), and pg_file_create_mode.

Referenced by _mdfd_openseg(), logical_rewrite_log_mapping(), mdcreate(), mdopenfork(), mdsyncfiletag(), OpenTemporaryFileInTablespace(), PathNameCreateTemporaryFile(), PathNameOpenTemporaryFile(), and ReorderBufferRestoreChanges().

{
    return PathNameOpenFilePerm(fileName, fileFlags, pg_file_create_mode);
}

PathNameOpenFilePerm()

File PathNameOpenFilePerm	(	const char *	fileName,
		int	fileFlags,
		mode_t	fileMode
	)

Definition at line 1371 of file fd.c.

References AllocateVfd(), BasicOpenFilePerm(), DO_DB, elog, ereport, errcode(), errmsg(), ERROR, vfd::fd, vfd::fdstate, vfd::fileFlags, vfd::fileMode, vfd::fileName, vfd::fileSize, free, FreeVfd(), Insert(), LOG, nfile, ReleaseLruFiles(), and vfd::resowner.

Referenced by PathNameOpenFile().

{
    char       *fnamecopy;
    File        file;
    Vfd        *vfdP;

    DO_DB(elog(LOG, "PathNameOpenFilePerm: %s %x %o",
               fileName, fileFlags, fileMode));

    /*
     * We need a malloc'd copy of the file name; fail cleanly if no room.
     */
    fnamecopy = strdup(fileName);
    if (fnamecopy == NULL)
        ereport(ERROR,
                (errcode(ERRCODE_OUT_OF_MEMORY),
                 errmsg("out of memory")));

    file = AllocateVfd();
    vfdP = &VfdCache[file];

    /* Close excess kernel FDs. */
    ReleaseLruFiles();

    vfdP->fd = BasicOpenFilePerm(fileName, fileFlags, fileMode);

    if (vfdP->fd < 0)
    {
        int         save_errno = errno;

        FreeVfd(file);
        free(fnamecopy);
        errno = save_errno;
        return -1;
    }
    ++nfile;
    DO_DB(elog(LOG, "PathNameOpenFile: success %d",
               vfdP->fd));

    Insert(file);

    vfdP->fileName = fnamecopy;
    /* Saved flags are adjusted to be OK for re-opening file */
    vfdP->fileFlags = fileFlags & ~(O_CREAT | O_TRUNC | O_EXCL);
    vfdP->fileMode = fileMode;
    vfdP->fileSize = 0;
    vfdP->fdstate = 0x0;
    vfdP->resowner = NULL;

    return file;
}

PathNameOpenTemporaryFile()

File PathNameOpenTemporaryFile

(

const char *

path

)

Definition at line 1672 of file fd.c.

References CurrentResourceOwner, ereport, errcode_for_file_access(), errmsg(), ERROR, PathNameOpenFile(), PG_BINARY, RegisterTemporaryFile(), and ResourceOwnerEnlargeFiles().

Referenced by SharedFileSetOpen().

{
    File        file;

    ResourceOwnerEnlargeFiles(CurrentResourceOwner);

    /* We open the file read-only. */
    file = PathNameOpenFile(path, O_RDONLY | PG_BINARY);

    /* If no such file, then we don't raise an error. */
    if (file <= 0 && errno != ENOENT)
        ereport(ERROR,
                (errcode_for_file_access(),
                 errmsg("could not open temporary file \"%s\": %m",
                        path)));

    if (file > 0)
    {
        /* Register it for automatic close. */
        RegisterTemporaryFile(file);
    }

    return file;
}

pg_fdatasync()

int pg_fdatasync

(

int

fd

)

Definition at line 420 of file fd.c.

References enableFsync, and fsync.

Referenced by issue_xlog_fsync().

{
    if (enableFsync)
    {
#ifdef HAVE_FDATASYNC
        return fdatasync(fd);
#else
        return fsync(fd);
#endif
    }
    else
        return 0;
}

pg_flush_data()

void pg_flush_data	(	int	fd,
		off_t	offset,
		off_t	nbytes
	)

Definition at line 440 of file fd.c.

References data_sync_elevel(), elevel, enableFsync, ereport, errcode_for_file_access(), errmsg(), FATAL, MAP_FAILED, and WARNING.

Referenced by copy_file(), FileWriteback(), and walkdir().

{
    /*
     * Right now file flushing is primarily used to avoid making later
     * fsync()/fdatasync() calls have less impact. Thus don't trigger flushes
     * if fsyncs are disabled - that's a decision we might want to make
     * configurable at some point.
     */
    if (!enableFsync)
        return;

    /*
     * We compile all alternatives that are supported on the current platform,
     * to find portability problems more easily.
     */
#if defined(HAVE_SYNC_FILE_RANGE)
    {
        int         rc;
        static bool not_implemented_by_kernel = false;

        if (not_implemented_by_kernel)
            return;

        /*
         * sync_file_range(SYNC_FILE_RANGE_WRITE), currently linux specific,
         * tells the OS that writeback for the specified blocks should be
         * started, but that we don't want to wait for completion.  Note that
         * this call might block if too much dirty data exists in the range.
         * This is the preferable method on OSs supporting it, as it works
         * reliably when available (contrast to msync()) and doesn't flush out
         * clean data (like FADV_DONTNEED).
         */
        rc = sync_file_range(fd, offset, nbytes,
                             SYNC_FILE_RANGE_WRITE);
        if (rc != 0)
        {
            int         elevel;

            /*
             * For systems that don't have an implementation of
             * sync_file_range() such as Windows WSL, generate only one
             * warning and then suppress all further attempts by this process.
             */
            if (errno == ENOSYS)
            {
                elevel = WARNING;
                not_implemented_by_kernel = true;
            }
            else
                elevel = data_sync_elevel(WARNING);

            ereport(elevel,
                    (errcode_for_file_access(),
                     errmsg("could not flush dirty data: %m")));
        }

        return;
    }
#endif
#if !defined(WIN32) && defined(MS_ASYNC)
    {
        void       *p;
        static int  pagesize = 0;

        /*
         * On several OSs msync(MS_ASYNC) on a mmap'ed file triggers
         * writeback. On linux it only does so if MS_SYNC is specified, but
         * then it does the writeback synchronously. Luckily all common linux
         * systems have sync_file_range().  This is preferable over
         * FADV_DONTNEED because it doesn't flush out clean data.
         *
         * We map the file (mmap()), tell the kernel to sync back the contents
         * (msync()), and then remove the mapping again (munmap()).
         */

        /* mmap() needs actual length if we want to map whole file */
        if (offset == 0 && nbytes == 0)
        {
            nbytes = lseek(fd, 0, SEEK_END);
            if (nbytes < 0)
            {
                ereport(WARNING,
                        (errcode_for_file_access(),
                         errmsg("could not determine dirty data size: %m")));
                return;
            }
        }

        /*
         * Some platforms reject partial-page mmap() attempts.  To deal with
         * that, just truncate the request to a page boundary.  If any extra
         * bytes don't get flushed, well, it's only a hint anyway.
         */

        /* fetch pagesize only once */
        if (pagesize == 0)
            pagesize = sysconf(_SC_PAGESIZE);

        /* align length to pagesize, dropping any fractional page */
        if (pagesize > 0)
            nbytes = (nbytes / pagesize) * pagesize;

        /* fractional-page request is a no-op */
        if (nbytes <= 0)
            return;

        /*
         * mmap could well fail, particularly on 32-bit platforms where there
         * may simply not be enough address space.  If so, silently fall
         * through to the next implementation.
         */
        if (nbytes <= (off_t) SSIZE_MAX)
            p = mmap(NULL, nbytes, PROT_READ, MAP_SHARED, fd, offset);
        else
            p = MAP_FAILED;

        if (p != MAP_FAILED)
        {
            int         rc;

            rc = msync(p, (size_t) nbytes, MS_ASYNC);
            if (rc != 0)
            {
                ereport(data_sync_elevel(WARNING),
                        (errcode_for_file_access(),
                         errmsg("could not flush dirty data: %m")));
                /* NB: need to fall through to munmap()! */
            }

            rc = munmap(p, (size_t) nbytes);
            if (rc != 0)
            {
                /* FATAL error because mapping would remain */
                ereport(FATAL,
                        (errcode_for_file_access(),
                         errmsg("could not munmap() while flushing data: %m")));
            }

            return;
        }
    }
#endif
#if defined(USE_POSIX_FADVISE) && defined(POSIX_FADV_DONTNEED)
    {
        int         rc;

        /*
         * Signal the kernel that the passed in range should not be cached
         * anymore. This has the, desired, side effect of writing out dirty
         * data, and the, undesired, side effect of likely discarding useful
         * clean cached blocks.  For the latter reason this is the least
         * preferable method.
         */

        rc = posix_fadvise(fd, offset, nbytes, POSIX_FADV_DONTNEED);

        if (rc != 0)
        {
            /* don't error out, this is just a performance optimization */
            ereport(WARNING,
                    (errcode_for_file_access(),
                     errmsg("could not flush dirty data: %m")));
        }

        return;
    }
#endif
}

pg_fsync()

int pg_fsync

(

int

fd

)

Definition at line 330 of file fd.c.

References Assert, pg_fsync_no_writethrough(), pg_fsync_writethrough(), S_ISDIR, stat, sync_method, and SYNC_METHOD_FSYNC_WRITETHROUGH.

Referenced by AddToDataDirLockFile(), assign_xlog_sync_method(), BootStrapXLOG(), CheckPointLogicalRewriteHeap(), CreateLockFile(), do_pg_start_backup(), durable_rename(), FileSync(), fsync_fname_ext(), heap_xlog_logical_rewrite(), readRecoverySignalFile(), RecreateTwoPhaseFile(), RestoreSlotFromDisk(), SaveSlotToPath(), SimpleLruFlush(), SlruPhysicalWritePage(), SnapBuildSerialize(), update_controlfile(), write_auto_conf_file(), write_relmap_file(), WriteControlFile(), writeTimeLineHistory(), writeTimeLineHistoryFile(), XLogFileCopy(), and XLogFileInit().

{
#if !defined(WIN32) && defined(USE_ASSERT_CHECKING)
    struct stat st;

    /*
     * Some operating system implementations of fsync() have requirements
     * about the file access modes that were used when their file descriptor
     * argument was opened, and these requirements differ depending on whether
     * the file descriptor is for a directory.
     *
     * For any file descriptor that may eventually be handed to fsync(), we
     * should have opened it with access modes that are compatible with
     * fsync() on all supported systems, otherwise the code may not be
     * portable, even if it runs ok on the current system.
     *
     * We assert here that a descriptor for a file was opened with write
     * permissions (either O_RDWR or O_WRONLY) and for a directory without
     * write permissions (O_RDONLY).
     *
     * Ignore any fstat errors and let the follow-up fsync() do its work.
     * Doing this sanity check here counts for the case where fsync() is
     * disabled.
     */
    if (fstat(fd, &st) == 0)
    {
        int         desc_flags = fcntl(fd, F_GETFL);

        /*
         * O_RDONLY is historically 0, so just make sure that for directories
         * no write flags are used.
         */
        if (S_ISDIR(st.st_mode))
            Assert((desc_flags & (O_RDWR | O_WRONLY)) == 0);
        else
            Assert((desc_flags & (O_RDWR | O_WRONLY)) != 0);
    }
    errno = 0;
#endif

    /* #if is to skip the sync_method test if there's no need for it */
#if defined(HAVE_FSYNC_WRITETHROUGH) && !defined(FSYNC_WRITETHROUGH_IS_FSYNC)
    if (sync_method == SYNC_METHOD_FSYNC_WRITETHROUGH)
        return pg_fsync_writethrough(fd);
    else
#endif
        return pg_fsync_no_writethrough(fd);
}

pg_fsync_no_writethrough()

int pg_fsync_no_writethrough

(

int

fd

)

Definition at line 385 of file fd.c.

References enableFsync, and fsync.

Referenced by issue_xlog_fsync(), and pg_fsync().

{
    if (enableFsync)
        return fsync(fd);
    else
        return 0;
}

pg_fsync_writethrough()

int pg_fsync_writethrough

(

int

fd

)

Definition at line 397 of file fd.c.

References enableFsync.

Referenced by issue_xlog_fsync(), pg_fsync(), signal_cleanup(), and test_sync().

{
    if (enableFsync)
    {
#ifdef WIN32
        return _commit(fd);
#elif defined(F_FULLFSYNC)
        return (fcntl(fd, F_FULLFSYNC, 0) == -1) ? -1 : 0;
#else
        errno = ENOSYS;
        return -1;
#endif
    }
    else
        return 0;
}

ReadDir()

struct dirent* ReadDir	(	DIR *	dir,
		const char *	dirname
	)

Definition at line 2569 of file fd.c.

References ERROR, and ReadDirExtended().

Referenced by calculate_database_size(), calculate_tablespace_size(), CheckPointLogicalRewriteHeap(), CheckPointSnapBuild(), CleanupBackupHistory(), copydir(), db_dir_size(), destroy_tablespace_directories(), directory_is_empty(), do_pg_start_backup(), dsm_cleanup_for_mmap(), get_ext_ver_list(), movedb(), perform_base_backup(), pg_available_extension_versions(), pg_available_extensions(), pg_logdir_ls_internal(), pg_ls_dir(), pg_ls_dir_files(), pg_tablespace_databases(), pg_tzenumerate_next(), pgarch_readyXlog(), pgstat_reset_remove_files(), RemoveNonParentXlogFiles(), RemoveOldXlogFiles(), RemoveTempXlogFiles(), ResetUnloggedRelations(), ResetUnloggedRelationsInDbspaceDir(), ResetUnloggedRelationsInTablespaceDir(), restoreTwoPhaseData(), sendDir(), SlruScanDirectory(), StartupReorderBuffer(), StartupReplicationSlots(), and UpdateLogicalMappings().

{
    return ReadDirExtended(dir, dirname, ERROR);
}

ReadDirExtended()

struct dirent* ReadDirExtended	(	DIR *	dir,
		const char *	dirname,
		int	elevel
	)

Definition at line 2584 of file fd.c.

References ereport, errcode_for_file_access(), errmsg(), and readdir().

Referenced by DeleteAllExportedSnapshotFiles(), ReadDir(), RelationCacheInitFileRemove(), RelationCacheInitFileRemoveInDir(), RemovePgTempFiles(), RemovePgTempFilesInDir(), RemovePgTempRelationFiles(), RemovePgTempRelationFilesInDbspace(), ReorderBufferCleanupSerializedTXNs(), scan_directory_ci(), and walkdir().

{
    struct dirent *dent;

    /* Give a generic message for AllocateDir failure, if caller didn't */
    if (dir == NULL)
    {
        ereport(elevel,
                (errcode_for_file_access(),
                 errmsg("could not open directory \"%s\": %m",
                        dirname)));
        return NULL;
    }

    errno = 0;
    if ((dent = readdir(dir)) != NULL)
        return dent;

    if (errno)
        ereport(elevel,
                (errcode_for_file_access(),
                 errmsg("could not read directory \"%s\": %m",
                        dirname)));
    return NULL;
}

RegisterTemporaryFile()

static void RegisterTemporaryFile ( File  file )

static

Definition at line 1330 of file fd.c.

References Assert, CurrentResourceOwner, FD_CLOSE_AT_EOXACT, vfd::fdstate, FileIsNotOpen, FileIsValid, have_xact_temporary_files, LruDelete(), ResourceOwnerRememberFile(), and vfd::resowner.

Referenced by OpenTemporaryFile(), PathNameCreateTemporaryFile(), and PathNameOpenTemporaryFile().

{
    ResourceOwnerRememberFile(CurrentResourceOwner, file);
    VfdCache[file].resowner = CurrentResourceOwner;

    /* Backup mechanism for closing at end of xact. */
    VfdCache[file].fdstate |= FD_CLOSE_AT_EOXACT;
    have_xact_temporary_files = true;
}

ReleaseLruFile()

static bool ReleaseLruFile ( void  )

static

Definition at line 1165 of file fd.c.

References Assert, DO_DB, elog, LOG, LruDelete(), vfd::lruMoreRecently, and nfile.

Referenced by AllocateDir(), AllocateFile(), BasicOpenFilePerm(), OpenPipeStream(), and ReleaseLruFiles().

{
    DO_DB(elog(LOG, "ReleaseLruFile. Opened %d", nfile));

    if (nfile > 0)
    {
        /*
         * There are opened files and so there should be at least one used vfd
         * in the ring.
         */
        Assert(VfdCache[0].lruMoreRecently != 0);
        LruDelete(VfdCache[0].lruMoreRecently);
        return true;            /* freed a file */
    }
    return false;               /* no files available to free */
}

ReleaseLruFiles()

static void ReleaseLruFiles ( void  )

static

Definition at line 1187 of file fd.c.

References max_safe_fds, nfile, numAllocatedDescs, and ReleaseLruFile().

Referenced by AllocateDir(), AllocateFile(), LruInsert(), OpenPipeStream(), OpenTransientFilePerm(), and PathNameOpenFilePerm().

{
    while (nfile + numAllocatedDescs >= max_safe_fds)
    {
        if (!ReleaseLruFile())
            break;
    }
}

RemovePgTempFiles()

void RemovePgTempFiles

(

void

)

Definition at line 2920 of file fd.c.

References AllocateDir(), dirent::d_name, FreeDir(), LOG, MAXPGPATH, PG_TEMP_FILES_DIR, ReadDirExtended(), RemovePgTempFilesInDir(), RemovePgTempRelationFiles(), snprintf, and TABLESPACE_VERSION_DIRECTORY.

Referenced by PostmasterMain().

{
    char        temp_path[MAXPGPATH + 10 + sizeof(TABLESPACE_VERSION_DIRECTORY) + sizeof(PG_TEMP_FILES_DIR)];
    DIR        *spc_dir;
    struct dirent *spc_de;

    /*
     * First process temp files in pg_default ($PGDATA/base)
     */
    snprintf(temp_path, sizeof(temp_path), "base/%s", PG_TEMP_FILES_DIR);
    RemovePgTempFilesInDir(temp_path, true, false);
    RemovePgTempRelationFiles("base");

    /*
     * Cycle through temp directories for all non-default tablespaces.
     */
    spc_dir = AllocateDir("pg_tblspc");

    while ((spc_de = ReadDirExtended(spc_dir, "pg_tblspc", LOG)) != NULL)
    {
        if (strcmp(spc_de->d_name, ".") == 0 ||
            strcmp(spc_de->d_name, "..") == 0)
            continue;

        snprintf(temp_path, sizeof(temp_path), "pg_tblspc/%s/%s/%s",
                 spc_de->d_name, TABLESPACE_VERSION_DIRECTORY, PG_TEMP_FILES_DIR);
        RemovePgTempFilesInDir(temp_path, true, false);

        snprintf(temp_path, sizeof(temp_path), "pg_tblspc/%s/%s",
                 spc_de->d_name, TABLESPACE_VERSION_DIRECTORY);
        RemovePgTempRelationFiles(temp_path);
    }

    FreeDir(spc_dir);

    /*
     * In EXEC_BACKEND case there is a pgsql_tmp directory at the top level of
     * DataDir as well.  However, that is *not* cleaned here because doing so
     * would create a race condition.  It's done separately, earlier in
     * postmaster startup.
     */
}

RemovePgTempFilesInDir()

void RemovePgTempFilesInDir	(	const char *	tmpdirname,
		bool	missing_ok,
		bool	unlink_all
	)

Definition at line 2979 of file fd.c.

References AllocateDir(), dirent::d_name, ereport, errcode_for_file_access(), errmsg(), FreeDir(), LOG, lstat, MAXPGPATH, PG_TEMP_FILE_PREFIX, ReadDirExtended(), RemovePgTempFilesInDir(), S_ISDIR, snprintf, and stat.

Referenced by PostmasterMain(), RemovePgTempFiles(), and RemovePgTempFilesInDir().

{
    DIR        *temp_dir;
    struct dirent *temp_de;
    char        rm_path[MAXPGPATH * 2];

    temp_dir = AllocateDir(tmpdirname);

    if (temp_dir == NULL && errno == ENOENT && missing_ok)
        return;

    while ((temp_de = ReadDirExtended(temp_dir, tmpdirname, LOG)) != NULL)
    {
        if (strcmp(temp_de->d_name, ".") == 0 ||
            strcmp(temp_de->d_name, "..") == 0)
            continue;

        snprintf(rm_path, sizeof(rm_path), "%s/%s",
                 tmpdirname, temp_de->d_name);

        if (unlink_all ||
            strncmp(temp_de->d_name,
                    PG_TEMP_FILE_PREFIX,
                    strlen(PG_TEMP_FILE_PREFIX)) == 0)
        {
            struct stat statbuf;

            if (lstat(rm_path, &statbuf) < 0)
            {
                ereport(LOG,
                        (errcode_for_file_access(),
                         errmsg("could not stat file \"%s\": %m", rm_path)));
                continue;
            }

            if (S_ISDIR(statbuf.st_mode))
            {
                /* recursively remove contents, then directory itself */
                RemovePgTempFilesInDir(rm_path, false, true);

                if (rmdir(rm_path) < 0)
                    ereport(LOG,
                            (errcode_for_file_access(),
                             errmsg("could not remove directory \"%s\": %m",
                                    rm_path)));
            }
            else
            {
                if (unlink(rm_path) < 0)
                    ereport(LOG,
                            (errcode_for_file_access(),
                             errmsg("could not remove file \"%s\": %m",
                                    rm_path)));
            }
        }
        else
            ereport(LOG,
                    (errmsg("unexpected file found in temporary-files directory: \"%s\"",
                            rm_path)));
    }

    FreeDir(temp_dir);
}

RemovePgTempRelationFiles()

static void RemovePgTempRelationFiles ( const char *  tsdirname )

static

Definition at line 3045 of file fd.c.

References AllocateDir(), dirent::d_name, FreeDir(), LOG, MAXPGPATH, ReadDirExtended(), RemovePgTempRelationFilesInDbspace(), and snprintf.

Referenced by RemovePgTempFiles().

{
    DIR        *ts_dir;
    struct dirent *de;
    char        dbspace_path[MAXPGPATH * 2];

    ts_dir = AllocateDir(tsdirname);

    while ((de = ReadDirExtended(ts_dir, tsdirname, LOG)) != NULL)
    {
        /*
         * We're only interested in the per-database directories, which have
         * numeric names.  Note that this code will also (properly) ignore "."
         * and "..".
         */
        if (strspn(de->d_name, "0123456789") != strlen(de->d_name))
            continue;

        snprintf(dbspace_path, sizeof(dbspace_path), "%s/%s",
                 tsdirname, de->d_name);
        RemovePgTempRelationFilesInDbspace(dbspace_path);
    }

    FreeDir(ts_dir);
}

RemovePgTempRelationFilesInDbspace()

static void RemovePgTempRelationFilesInDbspace ( const char *  dbspacedirname )

static

Definition at line 3073 of file fd.c.

References AllocateDir(), dirent::d_name, ereport, errcode_for_file_access(), errmsg(), FreeDir(), LOG, looks_like_temp_rel_name(), MAXPGPATH, ReadDirExtended(), and snprintf.

Referenced by RemovePgTempRelationFiles().

{
    DIR        *dbspace_dir;
    struct dirent *de;
    char        rm_path[MAXPGPATH * 2];

    dbspace_dir = AllocateDir(dbspacedirname);

    while ((de = ReadDirExtended(dbspace_dir, dbspacedirname, LOG)) != NULL)
    {
        if (!looks_like_temp_rel_name(de->d_name))
            continue;

        snprintf(rm_path, sizeof(rm_path), "%s/%s",
                 dbspacedirname, de->d_name);

        if (unlink(rm_path) < 0)
            ereport(LOG,
                    (errcode_for_file_access(),
                     errmsg("could not remove file \"%s\": %m",
                            rm_path)));
    }

    FreeDir(dbspace_dir);
}

ReportTemporaryFileUsage()

static void ReportTemporaryFileUsage ( const char *  path, off_t  size  )

static

Definition at line 1311 of file fd.c.

References ereport, errmsg(), LOG, log_temp_files, and pgstat_report_tempfile().

Referenced by FileClose(), and PathNameDeleteTemporaryFile().

{
    pgstat_report_tempfile(size);

    if (log_temp_files >= 0)
    {
        if ((size / 1024) >= log_temp_files)
            ereport(LOG,
                    (errmsg("temporary file: path \"%s\", size %lu",
                            path, (unsigned long) size)));
    }
}

reserveAllocatedDesc()

static bool reserveAllocatedDesc ( void  )

static

Definition at line 2169 of file fd.c.

References ereport, errcode(), errmsg(), ERROR, FD_MINFREE, malloc, max_safe_fds, maxAllocatedDescs, numAllocatedDescs, and realloc.

Referenced by AllocateDir(), AllocateFile(), OpenPipeStream(), and OpenTransientFilePerm().

{
    AllocateDesc *newDescs;
    int         newMax;

    /* Quick out if array already has a free slot. */
    if (numAllocatedDescs < maxAllocatedDescs)
        return true;

    /*
     * If the array hasn't yet been created in the current process, initialize
     * it with FD_MINFREE / 2 elements.  In many scenarios this is as many as
     * we will ever need, anyway.  We don't want to look at max_safe_fds
     * immediately because set_max_safe_fds() may not have run yet.
     */
    if (allocatedDescs == NULL)
    {
        newMax = FD_MINFREE / 2;
        newDescs = (AllocateDesc *) malloc(newMax * sizeof(AllocateDesc));
        /* Out of memory already?  Treat as fatal error. */
        if (newDescs == NULL)
            ereport(ERROR,
                    (errcode(ERRCODE_OUT_OF_MEMORY),
                     errmsg("out of memory")));
        allocatedDescs = newDescs;
        maxAllocatedDescs = newMax;
        return true;
    }

    /*
     * Consider enlarging the array beyond the initial allocation used above.
     * By the time this happens, max_safe_fds should be known accurately.
     *
     * We mustn't let allocated descriptors hog all the available FDs, and in
     * practice we'd better leave a reasonable number of FDs for VFD use.  So
     * set the maximum to max_safe_fds / 2.  (This should certainly be at
     * least as large as the initial size, FD_MINFREE / 2.)
     */
    newMax = max_safe_fds / 2;
    if (newMax > maxAllocatedDescs)
    {
        newDescs = (AllocateDesc *) realloc(allocatedDescs,
                                            newMax * sizeof(AllocateDesc));
        /* Treat out-of-memory as a non-fatal error. */
        if (newDescs == NULL)
            return false;
        allocatedDescs = newDescs;
        maxAllocatedDescs = newMax;
        return true;
    }

    /* Can't enlarge allocatedDescs[] any more. */
    return false;
}

set_max_safe_fds()

void set_max_safe_fds

(

void

)

Definition at line 938 of file fd.c.

References count_usable_fds(), DEBUG2, elog, ereport, errcode(), errdetail(), errmsg(), FATAL, FD_MINFREE, max_files_per_process, max_safe_fds, Min, and NUM_RESERVED_FDS.

Referenced by PostmasterMain().

{
    int         usable_fds;
    int         already_open;

    /*----------
     * We want to set max_safe_fds to
     *          MIN(usable_fds, max_files_per_process - already_open)
     * less the slop factor for files that are opened without consulting
     * fd.c.  This ensures that we won't exceed either max_files_per_process
     * or the experimentally-determined EMFILE limit.
     *----------
     */
    count_usable_fds(max_files_per_process,
                     &usable_fds, &already_open);

    max_safe_fds = Min(usable_fds, max_files_per_process - already_open);

    /*
     * Take off the FDs reserved for system() etc.
     */
    max_safe_fds -= NUM_RESERVED_FDS;

    /*
     * Make sure we still have enough to get by.
     */
    if (max_safe_fds < FD_MINFREE)
        ereport(FATAL,
                (errcode(ERRCODE_INSUFFICIENT_RESOURCES),
                 errmsg("insufficient file descriptors available to start server process"),
                 errdetail("System allows %d, we need at least %d.",
                           max_safe_fds + NUM_RESERVED_FDS,
                           FD_MINFREE + NUM_RESERVED_FDS)));

    elog(DEBUG2, "max_safe_fds = %d, usable_fds = %d, already_open = %d",
         max_safe_fds, usable_fds, already_open);
}

SetTempTablespaces()

void SetTempTablespaces	(	Oid *	tableSpaces,
		int	numSpaces
	)

Definition at line 2706 of file fd.c.

References Assert, nextTempTableSpace, numTempTableSpaces, random(), and tempTableSpaces.

Referenced by assign_temp_tablespaces(), and PrepareTempTablespaces().

{
    Assert(numSpaces >= 0);
    tempTableSpaces = tableSpaces;
    numTempTableSpaces = numSpaces;

    /*
     * Select a random starting point in the list.  This is to minimize
     * conflicts between backends that are most likely sharing the same list
     * of temp tablespaces.  Note that if we create multiple temp files in the
     * same transaction, we'll advance circularly through the list --- this
     * ensures that large temporary sort files are nicely spread across all
     * available tablespaces.
     */
    if (numSpaces > 1)
        nextTempTableSpace = random() % numSpaces;
    else
        nextTempTableSpace = 0;
}

SyncDataDirectory()

void SyncDataDirectory

(

void

)

Definition at line 3171 of file fd.c.

References datadir_fsync_fname(), DEBUG1, enableFsync, ereport, errcode_for_file_access(), errmsg(), LOG, lstat, pgwin32_is_junction(), stat, and walkdir().

Referenced by StartupXLOG().

{
    bool        xlog_is_symlink;

    /* We can skip this whole thing if fsync is disabled. */
    if (!enableFsync)
        return;

    /*
     * If pg_wal is a symlink, we'll need to recurse into it separately,
     * because the first walkdir below will ignore it.
     */
    xlog_is_symlink = false;

#ifndef WIN32
    {
        struct stat st;

        if (lstat("pg_wal", &st) < 0)
            ereport(LOG,
                    (errcode_for_file_access(),
                     errmsg("could not stat file \"%s\": %m",
                            "pg_wal")));
        else if (S_ISLNK(st.st_mode))
            xlog_is_symlink = true;
    }
#else
    if (pgwin32_is_junction("pg_wal"))
        xlog_is_symlink = true;
#endif

    /*
     * If possible, hint to the kernel that we're soon going to fsync the data
     * directory and its contents.  Errors in this step are even less
     * interesting than normal, so log them only at DEBUG1.
     */
#ifdef PG_FLUSH_DATA_WORKS
    walkdir(".", pre_sync_fname, false, DEBUG1);
    if (xlog_is_symlink)
        walkdir("pg_wal", pre_sync_fname, false, DEBUG1);
    walkdir("pg_tblspc", pre_sync_fname, true, DEBUG1);
#endif

    /*
     * Now we do the fsync()s in the same order.
     *
     * The main call ignores symlinks, so in addition to specially processing
     * pg_wal if it's a symlink, pg_tblspc has to be visited separately with
     * process_symlinks = true.  Note that if there are any plain directories
     * in pg_tblspc, they'll get fsync'd twice.  That's not an expected case
     * so we don't worry about optimizing it.
     */
    walkdir(".", datadir_fsync_fname, false, LOG);
    if (xlog_is_symlink)
        walkdir("pg_wal", datadir_fsync_fname, false, LOG);
    walkdir("pg_tblspc", datadir_fsync_fname, true, LOG);
}

TempTablespacePath()

void TempTablespacePath	(	char *	path,
		Oid	tablespace
	)

Definition at line 1552 of file fd.c.

References InvalidOid, MAXPGPATH, PG_TEMP_FILES_DIR, snprintf, and TABLESPACE_VERSION_DIRECTORY.

Referenced by OpenTemporaryFileInTablespace(), pg_ls_tmpdir(), SharedFileSetCreate(), and SharedFileSetPath().

{
    /*
     * Identify the tempfile directory for this tablespace.
     *
     * If someone tries to specify pg_global, use pg_default instead.
     */
    if (tablespace == InvalidOid ||
        tablespace == DEFAULTTABLESPACE_OID ||
        tablespace == GLOBALTABLESPACE_OID)
        snprintf(path, MAXPGPATH, "base/%s", PG_TEMP_FILES_DIR);
    else
    {
        /* All other tablespaces are accessed via symlinks */
        snprintf(path, MAXPGPATH, "pg_tblspc/%u/%s/%s",
                 tablespace, TABLESPACE_VERSION_DIRECTORY,
                 PG_TEMP_FILES_DIR);
    }
}

TempTablespacesAreSet()

bool TempTablespacesAreSet

(

void

)

Definition at line 2734 of file fd.c.

References numTempTableSpaces.

Referenced by GetTempTablespaces(), and PrepareTempTablespaces().

{
    return (numTempTableSpaces >= 0);
}

unlink_if_exists_fname()

static void unlink_if_exists_fname ( const char *  fname, bool  isdir, int  elevel  )

static

Definition at line 3355 of file fd.c.

References ereport, errcode_for_file_access(), errmsg(), and PathNameDeleteTemporaryFile().

Referenced by PathNameDeleteTemporaryDir().

{
    if (isdir)
    {
        if (rmdir(fname) != 0 && errno != ENOENT)
            ereport(elevel,
                    (errcode_for_file_access(),
                     errmsg("could not remove directory \"%s\": %m", fname)));
    }
    else
    {
        /* Use PathNameDeleteTemporaryFile to report filesize */
        PathNameDeleteTemporaryFile(fname, false);
    }
}

walkdir()

static void walkdir ( const char *  path, void(*)(const char *fname, bool isdir, int elevel)  action, bool  process_symlinks, int  elevel  )

static

Definition at line 3245 of file fd.c.

References generate_unaccent_rules::action, AllocateDir(), CHECK_FOR_INTERRUPTS, CloseTransientFile(), dirent::d_name, elevel, ereport, errcode_for_file_access(), errmsg(), vfd::fd, FreeDir(), lstat, MAXPGPATH, OpenTransientFile(), PG_BINARY, pg_flush_data(), ReadDirExtended(), S_ISDIR, S_ISREG, snprintf, stat, and subpath().

Referenced by PathNameDeleteTemporaryDir(), and SyncDataDirectory().

{
    DIR        *dir;
    struct dirent *de;

    dir = AllocateDir(path);

    while ((de = ReadDirExtended(dir, path, elevel)) != NULL)
    {
        char        subpath[MAXPGPATH * 2];
        struct stat fst;
        int         sret;

        CHECK_FOR_INTERRUPTS();

        if (strcmp(de->d_name, ".") == 0 ||
            strcmp(de->d_name, "..") == 0)
            continue;

        snprintf(subpath, sizeof(subpath), "%s/%s", path, de->d_name);

        if (process_symlinks)
            sret = stat(subpath, &fst);
        else
            sret = lstat(subpath, &fst);

        if (sret < 0)
        {
            ereport(elevel,
                    (errcode_for_file_access(),
                     errmsg("could not stat file \"%s\": %m", subpath)));
            continue;
        }

        if (S_ISREG(fst.st_mode))
            (*action) (subpath, false, elevel);
        else if (S_ISDIR(fst.st_mode))
            walkdir(subpath, action, false, elevel);
    }

    FreeDir(dir);               /* we ignore any error here */

    /*
     * It's important to fsync the destination directory itself as individual
     * file fsyncs don't guarantee that the directory entry for the file is
     * synced.  However, skip this if AllocateDir failed; the action function
     * might not be robust against that.
     */
    if (dir)
        (*action) (path, true, elevel);
}

Variable Documentation

allocatedDescs

AllocateDesc* allocatedDescs = NULL

static

Definition at line 244 of file fd.c.

data_sync_retry

bool data_sync_retry = false

Definition at line 148 of file fd.c.

Referenced by data_sync_elevel().

have_xact_temporary_files

bool have_xact_temporary_files = false

static

Definition at line 208 of file fd.c.

Referenced by CleanupTempFiles(), and RegisterTemporaryFile().

max_files_per_process

int max_files_per_process = 1000

Definition at line 132 of file fd.c.

Referenced by set_max_safe_fds().

max_safe_fds

int max_safe_fds = 32

Definition at line 145 of file fd.c.

Referenced by PostmasterMarkPIDForWorkerNotify(), ReleaseLruFiles(), reserveAllocatedDesc(), and set_max_safe_fds().

maxAllocatedDescs

int maxAllocatedDescs = 0

static

Definition at line 243 of file fd.c.

Referenced by AllocateDir(), AllocateFile(), OpenPipeStream(), OpenTransientFilePerm(), and reserveAllocatedDesc().

nextTempTableSpace

int nextTempTableSpace = 0

static

Definition at line 258 of file fd.c.

Referenced by GetNextTempTableSpace(), and SetTempTablespaces().

nfile

int nfile = 0

static

Definition at line 202 of file fd.c.

Referenced by FileClose(), LruDelete(), LruInsert(), PathNameOpenFilePerm(), ReleaseLruFile(), and ReleaseLruFiles().

numAllocatedDescs

int numAllocatedDescs = 0

static

Definition at line 242 of file fd.c.

Referenced by AllocateDir(), AllocateFile(), AtEOSubXact_Files(), CleanupTempFiles(), ClosePipeStream(), CloseTransientFile(), FreeDesc(), FreeDir(), FreeFile(), OpenPipeStream(), OpenTransientFilePerm(), ReleaseLruFiles(), and reserveAllocatedDesc().

numTempTableSpaces

int numTempTableSpaces = -1

static

Definition at line 257 of file fd.c.

Referenced by AtEOXact_Files(), GetNextTempTableSpace(), GetTempTablespaces(), OpenTemporaryFile(), SetTempTablespaces(), and TempTablespacesAreSet().

SizeVfdCache

Size SizeVfdCache = 0

static

Definition at line 197 of file fd.c.

Referenced by AllocateVfd(), CleanupTempFiles(), closeAllVfds(), and InitFileAccess().

tempFileCounter

long tempFileCounter = 0

static

Definition at line 250 of file fd.c.

Referenced by OpenTemporaryFileInTablespace().

temporary_files_size

uint64 temporary_files_size = 0

static

Definition at line 216 of file fd.c.

Referenced by FileClose(), FileTruncate(), and FileWrite().

tempTableSpaces

Oid* tempTableSpaces = NULL

static

Definition at line 256 of file fd.c.

Referenced by AtEOXact_Files(), GetNextTempTableSpace(), GetTempTablespaces(), and SetTempTablespaces().

VfdCache

Vfd* VfdCache

static

Definition at line 196 of file fd.c.