pg_upgrade: Don't overwrite existing files.

For historical reasons, copyFile and rewriteVisibilityMap took a force
argument which was always passed as true, meaning that any existing
file should be overwritten.  However, it seems much safer to instead
fail if a file we need to write already exists.

While we're at it, remove the "force" argument altogether, since it was
never passed as anything other than true (and now we would never pass
it as anything other than false, if we kept it).

Noted by Andres Freund during post-commit review of the patch that added
rewriteVisibilityMap, commit 7087166a88fe0c04fc6636d0d6d6bea1737fc1fb,
but this also changes the behavior when copying files without rewriting
them.

Patch by Masahiko Sawada.
This commit is contained in:
Robert Haas 2016-06-06 09:51:56 -04:00
parent 932b97a011
commit e191a69005
3 changed files with 13 additions and 14 deletions

View File

@ -22,7 +22,7 @@
#ifndef WIN32
static int copy_file(const char *fromfile, const char *tofile, bool force);
static int copy_file(const char *fromfile, const char *tofile);
#else
static int win32_pghardlink(const char *src, const char *dst);
#endif
@ -34,12 +34,12 @@ static int win32_pghardlink(const char *src, const char *dst);
* Copies a relation file from src to dst.
*/
const char *
copyFile(const char *src, const char *dst, bool force)
copyFile(const char *src, const char *dst)
{
#ifndef WIN32
if (copy_file(src, dst, force) == -1)
if (copy_file(src, dst) == -1)
#else
if (CopyFile(src, dst, !force) == 0)
if (CopyFile(src, dst, true) == 0)
#endif
return getErrorText();
else
@ -68,7 +68,7 @@ linkFile(const char *src, const char *dst)
#ifndef WIN32
static int
copy_file(const char *srcfile, const char *dstfile, bool force)
copy_file(const char *srcfile, const char *dstfile)
{
#define COPY_BUF_SIZE (50 * BLCKSZ)
@ -87,7 +87,7 @@ copy_file(const char *srcfile, const char *dstfile, bool force)
if ((src_fd = open(srcfile, O_RDONLY, 0)) < 0)
return -1;
if ((dest_fd = open(dstfile, O_RDWR | O_CREAT | (force ? 0 : O_EXCL), S_IRUSR | S_IWUSR)) < 0)
if ((dest_fd = open(dstfile, O_RDWR | O_CREAT | O_EXCL, S_IRUSR | S_IWUSR)) < 0)
{
save_errno = errno;
@ -159,7 +159,7 @@ copy_file(const char *srcfile, const char *dstfile, bool force)
* VACUUM.
*/
const char *
rewriteVisibilityMap(const char *fromfile, const char *tofile, bool force)
rewriteVisibilityMap(const char *fromfile, const char *tofile)
{
int src_fd = 0;
int dst_fd = 0;
@ -186,7 +186,7 @@ rewriteVisibilityMap(const char *fromfile, const char *tofile, bool force)
return getErrorText();
}
if ((dst_fd = open(tofile, O_RDWR | O_CREAT | (force ? 0 : O_EXCL), S_IRUSR | S_IWUSR)) < 0)
if ((dst_fd = open(tofile, O_RDWR | O_CREAT | O_EXCL, S_IRUSR | S_IWUSR)) < 0)
{
close(src_fd);
return getErrorText();

View File

@ -367,10 +367,9 @@ bool pid_lock_file_exists(const char *datadir);
/* file.c */
const char *copyFile(const char *src, const char *dst, bool force);
const char *copyFile(const char *src, const char *dst);
const char *linkFile(const char *src, const char *dst);
const char *rewriteVisibilityMap(const char *fromfile, const char *tofile,
bool force);
const char *rewriteVisibilityMap(const char *fromfile, const char *tofile);
void check_hard_link(void);
FILE *fopen_priv(const char *path, const char *mode);

View File

@ -248,9 +248,9 @@ transfer_relfile(FileNameMap *map, const char *type_suffix, bool vm_must_add_fro
/* Rewrite visibility map if needed */
if (vm_must_add_frozenbit && (strcmp(type_suffix, "_vm") == 0))
msg = rewriteVisibilityMap(old_file, new_file, true);
msg = rewriteVisibilityMap(old_file, new_file);
else
msg = copyFile(old_file, new_file, true);
msg = copyFile(old_file, new_file);
if (msg)
pg_fatal("error while copying relation \"%s.%s\" (\"%s\" to \"%s\"): %s\n",
@ -262,7 +262,7 @@ transfer_relfile(FileNameMap *map, const char *type_suffix, bool vm_must_add_fro
/* Rewrite visibility map if needed */
if (vm_must_add_frozenbit && (strcmp(type_suffix, "_vm") == 0))
msg = rewriteVisibilityMap(old_file, new_file, true);
msg = rewriteVisibilityMap(old_file, new_file);
else
msg = linkFile(old_file, new_file);