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Move copydir.c from src/port to src/backend/storage/file

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The previous commit to make copydir() interruptible prevented
postgres.exe from linking on MinGW and Cygwin, because on those
platforms libpgport_srv.a can't freely reference symbols defined
by the backend.  Since that code is already backend-specific anyway,
just move the whole file into the backend rather than adding further
kludges to deal with the symbols needed by CHECK_FOR_INTERRUPTS().

This probably needs some further cleanup, but this commit just moves
the file as-is, which should hopefully be enough to turn the
buildfarm green again.
This commit is contained in:
Robert Haas
2010-07-02 17:03:30 +00:00
parent 621cf14620
commit bb0fe9feb9
3 changed files with 5 additions and 5 deletions
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272
src/backend/storage/file/copydir.c Normal file
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@ -0,0 +1,272 @@
/*-------------------------------------------------------------------------
*
* copydir.c
* copies a directory
*
* Portions Copyright (c) 1996-2010, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* While "xcopy /e /i /q" works fine for copying directories, on Windows XP
* it requires a Window handle which prevents it from working when invoked
* as a service.
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/storage/file/copydir.c,v 1.1 2010/07/02 17:03:30 rhaas Exp $
*
*-------------------------------------------------------------------------
*/
#include "postgres.h"
#include <fcntl.h>
#include <unistd.h>
#include <sys/stat.h>
#include "storage/fd.h"
#include "miscadmin.h"
/*
* On Windows, call non-macro versions of palloc; we can't reference
* CurrentMemoryContext in this file because of PGDLLIMPORT conflict.
*/
#if defined(WIN32) || defined(__CYGWIN__)
#undef palloc
#undef pstrdup
#define palloc(sz) pgport_palloc(sz)
#define pstrdup(str) pgport_pstrdup(str)
#endif
static void copy_file(char *fromfile, char *tofile);
static void fsync_fname(char *fname, bool isdir);
/*
* copydir: copy a directory
*
* If recurse is false, subdirectories are ignored. Anything that's not
* a directory or a regular file is ignored.
*/
void
copydir(char *fromdir, char *todir, bool recurse)
{
DIR *xldir;
struct dirent *xlde;
char fromfile[MAXPGPATH];
char tofile[MAXPGPATH];
if (mkdir(todir, S_IRUSR | S_IWUSR | S_IXUSR) != 0)
ereport(ERROR,
(errcode_for_file_access(),
errmsg("could not create directory \"%s\": %m", todir)));
xldir = AllocateDir(fromdir);
if (xldir == NULL)
ereport(ERROR,
(errcode_for_file_access(),
errmsg("could not open directory \"%s\": %m", fromdir)));
while ((xlde = ReadDir(xldir, fromdir)) != NULL)
{
struct stat fst;
/* If we got a cancel signal during the copy of the directory, quit */
CHECK_FOR_INTERRUPTS();
if (strcmp(xlde->d_name, ".") == 0 ||
strcmp(xlde->d_name, "..") == 0)
continue;
snprintf(fromfile, MAXPGPATH, "%s/%s", fromdir, xlde->d_name);
snprintf(tofile, MAXPGPATH, "%s/%s", todir, xlde->d_name);
if (lstat(fromfile, &fst) < 0)
ereport(ERROR,
(errcode_for_file_access(),
errmsg("could not stat file \"%s\": %m", fromfile)));
if (S_ISDIR(fst.st_mode))
{
/* recurse to handle subdirectories */
if (recurse)
copydir(fromfile, tofile, true);
}
else if (S_ISREG(fst.st_mode))
copy_file(fromfile, tofile);
}
FreeDir(xldir);
/*
* Be paranoid here and fsync all files to ensure the copy is really done.
*/
xldir = AllocateDir(todir);
if (xldir == NULL)
ereport(ERROR,
(errcode_for_file_access(),
errmsg("could not open directory \"%s\": %m", todir)));
while ((xlde = ReadDir(xldir, todir)) != NULL)
{
struct stat fst;
if (strcmp(xlde->d_name, ".") == 0 ||
strcmp(xlde->d_name, "..") == 0)
continue;
snprintf(tofile, MAXPGPATH, "%s/%s", todir, xlde->d_name);
/*
* We don't need to sync subdirectories here since the recursive
* copydir will do it before it returns
*/
if (lstat(tofile, &fst) < 0)
ereport(ERROR,
(errcode_for_file_access(),
errmsg("could not stat file \"%s\": %m", tofile)));
if (S_ISREG(fst.st_mode))
fsync_fname(tofile, false);
}
FreeDir(xldir);
/*
* 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. Recent versions of ext4 have made the window much wider but
* it's been true for ext3 and other filesystems in the past.
*/
fsync_fname(todir, true);
}
/*
* copy one file
*/
static void
copy_file(char *fromfile, char *tofile)
{
char *buffer;
int srcfd;
int dstfd;
int nbytes;
off_t offset;
/* Use palloc to ensure we get a maxaligned buffer */
#define COPY_BUF_SIZE (8 * BLCKSZ)
buffer = palloc(COPY_BUF_SIZE);
/*
* Open the files
*/
srcfd = BasicOpenFile(fromfile, O_RDONLY | PG_BINARY, 0);
if (srcfd < 0)
ereport(ERROR,
(errcode_for_file_access(),
errmsg("could not open file \"%s\": %m", fromfile)));
dstfd = BasicOpenFile(tofile, O_RDWR | O_CREAT | O_EXCL | PG_BINARY,
S_IRUSR | S_IWUSR);
if (dstfd < 0)
ereport(ERROR,
(errcode_for_file_access(),
errmsg("could not create file \"%s\": %m", tofile)));
/*
* Do the data copying.
*/
for (offset = 0;; offset += nbytes)
{
/* If we got a cancel signal during the copy of the file, quit */
CHECK_FOR_INTERRUPTS();
nbytes = read(srcfd, buffer, COPY_BUF_SIZE);
if (nbytes < 0)
ereport(ERROR,
(errcode_for_file_access(),
errmsg("could not read file \"%s\": %m", fromfile)));
if (nbytes == 0)
break;
errno = 0;
if ((int) write(dstfd, buffer, nbytes) != nbytes)
{
/* if write didn't set errno, assume problem is no disk space */
if (errno == 0)
errno = ENOSPC;
ereport(ERROR,
(errcode_for_file_access(),
errmsg("could not write to file \"%s\": %m", tofile)));
}
/*
* We fsync the files later but first flush them to avoid spamming the
* cache and hopefully get the kernel to start writing them out before
* the fsync comes.
*/
pg_flush_data(dstfd, offset, nbytes);
}
if (close(dstfd))
ereport(ERROR,
(errcode_for_file_access(),
errmsg("could not close file \"%s\": %m", tofile)));
close(srcfd);
pfree(buffer);
}
/*
* fsync a file
*
* Try to fsync directories but ignore errors that indicate the OS
* just doesn't allow/require fsyncing directories.
*/
static void
fsync_fname(char *fname, bool isdir)
{
int fd;
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
*/
if (!isdir)
fd = BasicOpenFile(fname,
O_RDWR | PG_BINARY,
S_IRUSR | S_IWUSR);
else
fd = BasicOpenFile(fname,
O_RDONLY | PG_BINARY,
S_IRUSR | S_IWUSR);
/*
* Some OSs don't allow us to open directories at all
* (Windows returns EACCES)
*/
if (fd < 0 && isdir && (errno == EISDIR || errno == EACCES))
return;
else if (fd < 0)
ereport(ERROR,
(errcode_for_file_access(),
errmsg("could not open file \"%s\": %m", fname)));
returncode = pg_fsync(fd);
/* Some OSs don't allow us to fsync directories at all */
if (returncode != 0 && isdir && errno == EBADF)
{
close(fd);
return;
}
if (returncode != 0)
ereport(ERROR,
(errcode_for_file_access(),
errmsg("could not fsync file \"%s\": %m", fname)));
close(fd);
}