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/*-------------------------------------------------------------------------
*
* dirmod.c
* rename/unlink()
*
* Portions Copyright (c) 1996-2003, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* These are replacement versions of unlink and rename that work on
* Win32 (NT, Win2k, XP). replace() doesn't work on Win95/98/Me.
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/port/dirmod.c,v 1.10 2004/02/02 22:20:33 momjian Exp $
*
*-------------------------------------------------------------------------
*/
#ifndef TEST_VERSION
#if defined(WIN32) || defined(CYGWIN)
#ifndef FRONTEND
#include "postgres.h"
#else
#include "postgres_fe.h"
#endif
#undef rename
#undef unlink
int
pgrename(const char *from, const char *to)
{
int loops = 0;
#ifdef WIN32
while (!MoveFileEx(from, to, MOVEFILE_REPLACE_EXISTING))
#endif
#ifdef CYGWIN
while (rename(from, to) < 0)
#endif
{
#ifdef WIN32
if (GetLastError() != ERROR_ACCESS_DENIED)
#endif
#ifdef CYGWIN
if (errno != EACCES)
#endif
/* set errno? */
return -1;
Sleep(100); /* ms */
if (loops == 30)
#ifndef FRONTEND
elog(LOG, "could not rename \"%s\" to \"%s\", continuing to try",
from, to);
#else
fprintf(stderr, "could not rename \"%s\" to \"%s\", continuing to try\n",
from, to);
#endif
loops++;
}
if (loops > 30)
#ifndef FRONTEND
elog(LOG, "completed rename of \"%s\" to \"%s\"", from, to);
#else
fprintf(stderr, "completed rename of \"%s\" to \"%s\"\n", from, to);
#endif
return 0;
}
int
pgunlink(const char *path)
{
int loops = 0;
while (unlink(path))
{
if (errno != EACCES)
/* set errno? */
return -1;
Sleep(100); /* ms */
if (loops == 30)
#ifndef FRONTEND
elog(LOG, "could not unlink \"%s\", continuing to try",
path);
#else
fprintf(stderr, "could not unlink \"%s\", continuing to try\n",
path);
#endif
loops++;
}
if (loops > 30)
#ifndef FRONTEND
elog(LOG, "completed unlink of \"%s\"", path);
#else
fprintf(stderr, "completed unlink of \"%s\"\n", path);
#endif
return 0;
}
#endif
#else
/*
* Illustrates problem with Win32 rename() and unlink()
* under concurrent access.
*
* Run with arg '1', then less than 5 seconds later, run with
* arg '2' (rename) or '3'(unlink) to see the problem.
*/
#include <stdio.h>
#include <stdlib.h>
#include <errno.h>
#include <windows.h>
#define halt(str) \
do { \
fputs(str, stderr); \
exit(1); \
} while (0)
int
main(int argc, char *argv[])
{
FILE *fd;
if (argc != 2)
halt("Arg must be '1' (test), '2' (rename), or '3' (unlink)\n"
"Run '1' first, then less than 5 seconds later, run\n"
"'2' to test rename, or '3' to test unlink.\n");
if (atoi(argv[1]) == 1)
{
if ((fd = fopen("/rtest.txt", "w")) == NULL)
halt("Can not create file\n");
fclose(fd);
if ((fd = fopen("/rtest.txt", "r")) == NULL)
halt("Can not open file\n");
Sleep(5000);
}
else if (atoi(argv[1]) == 2)
{
unlink("/rtest.new");
if ((fd = fopen("/rtest.new", "w")) == NULL)
halt("Can not create file\n");
fclose(fd);
while (!MoveFileEx("/rtest.new", "/rtest.txt", MOVEFILE_REPLACE_EXISTING))
{
if (GetLastError() != ERROR_ACCESS_DENIED)
halt("Unknown failure\n");
else
fprintf(stderr, "move failed\n");
Sleep(500);
}
halt("move successful\n");
}
else if (atoi(argv[1]) == 3)
{
while (unlink("/rtest.txt"))
{
if (errno != EACCES)
halt("Unknown failure\n");
else
fprintf(stderr, "unlink failed\n");
Sleep(500);
}
halt("unlink successful\n");
}
else
halt("invalid arg\n");
return 0;
}
#endif
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