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/*
* These are replacement versions of unlink and rename that work on
* Win32 (NT, Win2k, XP). replace() doesn't work on Win95/98/Me.
*
*/
#ifndef TEST_VERSION
#include "postgres.h"
#undef rename
#undef unlink
int pgrename(const char *from, const char *to)
{
int loops = 0;
while (!MoveFileEx(from, to, MOVEFILE_REPLACE_EXISTING))
{
if (GetLastError() != ERROR_ACCESS_DENIED)
/* set errno? */
return -1;
Sleep(100); /* ms */
if (loops == 10)
#ifndef FRONTEND
elog(LOG, "Unable to rename %s to %s, continuing to try", from, to);
#else
fprintf(stderr, "Unable to rename %s to %s, continuing to try\n", from, to);
#endif
loops++;
}
if (loops > 10)
#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 == 10)
#ifndef FRONTEND
elog(LOG, "Unable to unlink %s, continuing to try", path);
#else
fprintf(stderr, "Unable to unlink %s, continuing to try\n", path);
#endif
loops++;
}
if (loops > 10)
#ifndef FRONTEND
elog(LOG, "Completed unlink of %s", path);
#else
fprintf(stderr, "Completed unlink of %s\n", path);
#endif
return 0;
}
#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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