From: Joel Rosdahl <joel@rosdahl.net>
Date: Wed, 21 Jul 2010 13:15:42 +0000 (+0200)
Subject: Introduce x_rename(), which unlink()s destination if necessary before rename()
X-Git-Tag: v3.1~135
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=0ea9d9e0a379db26417f4d55e807d2a933208f2b;p=thirdparty%2Fccache.git

Introduce x_rename(), which unlink()s destination if necessary before rename()
---

diff --git a/ccache.c b/ccache.c
index a1ca78cd0..c0200462a 100644
--- a/ccache.c
+++ b/ccache.c
@@ -634,8 +634,7 @@ static void to_cache(struct args *args)
 		char *tmp_stderr2;
 
 		tmp_stderr2 = format("%s.tmp.stderr2.%s", cached_obj, tmp_string());
-		unlink(tmp_stderr2);
-		if (rename(tmp_stderr, tmp_stderr2)) {
+		if (x_rename(tmp_stderr, tmp_stderr2)) {
 			cc_log("Failed to rename %s to %s", tmp_stderr, tmp_stderr2);
 			failed();
 		}
diff --git a/ccache.h b/ccache.h
index f07f3a3b1..5b8d287d9 100644
--- a/ccache.h
+++ b/ccache.h
@@ -119,6 +119,7 @@ int is_full_path(const char *path);
 void update_mtime(const char *path);
 void *x_fmmap(const char *fname, off_t *size, const char *errstr);
 int x_munmap(void *addr, size_t length);
+int x_rename(const char *oldpath, const char *newpath);
 
 /* ------------------------------------------------------------------------- */
 /* stats.c */
diff --git a/manifest.c b/manifest.c
index 4e8b949ae..4518fab8c 100644
--- a/manifest.c
+++ b/manifest.c
@@ -682,8 +682,7 @@ int manifest_put(const char *manifest_path, struct file_hash *object_hash,
 	if (write_manifest(f2, mf)) {
 		gzclose(f2);
 		f2 = NULL;
-		unlink(manifest_path);
-		if (rename(tmp_file, manifest_path) == 0) {
+		if (x_rename(tmp_file, manifest_path) == 0) {
 			ret = 1;
 		} else {
 			cc_log("Failed to rename %s to %s",
diff --git a/util.c b/util.c
index e9946eaa5..2455748b5 100644
--- a/util.c
+++ b/util.c
@@ -299,9 +299,7 @@ int copy_file(const char *src, const char *dest, int compress_dest)
 		goto error;
 	}
 
-	unlink(dest);
-
-	if (rename(tmp_name, dest) == -1) {
+	if (x_rename(tmp_name, dest) == -1) {
 		cc_log("rename error: %s", strerror(errno));
 		goto error;
 	}
@@ -347,8 +345,7 @@ move_uncompressed_file(const char *src, const char *dest, int compress_dest)
 	if (compress_dest) {
 		return move_file(src, dest, compress_dest);
 	} else {
-		unlink(dest);
-		return rename(src, dest);
+		return x_rename(src, dest);
 	}
 }
 
@@ -1105,3 +1102,15 @@ int x_munmap(void *addr, size_t length)
 	return munmap(addr, length);
 #endif
 }
+
+/*
+ * Rename oldpath to newpath (deleting newpath).
+ */
+int x_rename(const char *oldpath, const char *newpath)
+{
+#ifdef _WIN32
+	/* Windows' rename() refuses to overwrite an existing file. */
+	unlink(newpath);
+#endif
+	return rename(oldpath, newpath);
+}