compat/mingw.c: Teach mingw_rename() to replace read-only files
On POSIX, rename() can replace files that are not writable. On Windows, however, read-only files cannot be replaced without additional efforts: We have to make the destination writable first. Since the situations where the destination is read-only are rare, we do not make the destination writable on every invocation, but only if the first try to rename a file failed with an "access denied" error. Signed-off-by: Johannes Sixt <j6t@kdbg.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Johannes Sixt committed
Nov 19, 2008 at 17:25 UTC
632f70178784291bd2974e07fdcd2b8e8608f252
1 file changed
+12
-3
compat/mingw.c
+12
-3
@@ -865,6 +865,8 @@ int mingw_connect(int sockfd, struct sockaddr *sa, size_t sz)
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#undef rename
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int mingw_rename(const char *pold, const char *pnew)
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{
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+ DWORD attrs;
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+
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/*
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* Try native rename() first to get errno right.
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* It is based on MoveFile(), which cannot overwrite existing files.
@@ -876,12 +878,19 @@ int mingw_rename(const char *pold, const char *pnew)
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if (MoveFileEx(pold, pnew, MOVEFILE_REPLACE_EXISTING))
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return 0;
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/* TODO: translate more errors */
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- if (GetLastError() == ERROR_ACCESS_DENIED) {
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- DWORD attrs = GetFileAttributes(pnew);
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- if (attrs != INVALID_FILE_ATTRIBUTES && (attrs & FILE_ATTRIBUTE_DIRECTORY)) {
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+ if (GetLastError() == ERROR_ACCESS_DENIED &&
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+ (attrs = GetFileAttributes(pnew)) != INVALID_FILE_ATTRIBUTES) {
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+ if (attrs & FILE_ATTRIBUTE_DIRECTORY) {
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errno = EISDIR;
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return -1;
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}
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+ if ((attrs & FILE_ATTRIBUTE_READONLY) &&
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+ SetFileAttributes(pnew, attrs & ~FILE_ATTRIBUTE_READONLY)) {
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+ if (MoveFileEx(pold, pnew, MOVEFILE_REPLACE_EXISTING))
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+ return 0;
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+ /* revert file attributes on failure */
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+ SetFileAttributes(pnew, attrs);
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+ }
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}
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errno = EACCES;
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return -1;