Don't overwrite a file that is currently opened

First move it to a temporary location. Ideally this should only be done on
operating systems that don't allow this operation (ie: Windows).

diff --git a/ccache.c b/ccache.c
index 945cf1b0ed454ef74d80ccd57487997531bfebaa..fabd09a3eebfc77d7c2f5e7c7a5f8c433f9bdf06 100644 (file)
--- a/ccache.c
+++ b/ccache.c
@@ -651,18 +651,23 @@ static void to_cache(ARGS *args)
                int fd_cpp_stderr;
                int fd_real_stderr;
                int fd_result;
+               char *tmp_stderr2;
 
+               x_asprintf(&tmp_stderr2, "%s.tmp.stderr2.%s", cached_obj, tmp_string());
+               if (rename(tmp_stderr, tmp_stderr2)) {
+                       cc_log("Failed to rename %s to %s", tmp_stderr, tmp_stderr2);
+                       failed();
+               }
                fd_cpp_stderr = open(cpp_stderr, O_RDONLY | O_BINARY);
                if (fd_cpp_stderr == -1) {
                        cc_log("Failed opening %s", cpp_stderr);
                        failed();
                }
-               fd_real_stderr = open(tmp_stderr, O_RDONLY | O_BINARY);
+               fd_real_stderr = open(tmp_stderr2, O_RDONLY | O_BINARY);
                if (fd_real_stderr == -1) {
-                       cc_log("Failed opening %s", tmp_stderr);
+                       cc_log("Failed opening %s", tmp_stderr2);
                        failed();
                }
-               unlink(tmp_stderr);
                fd_result = open(tmp_stderr,
                                 O_WRONLY | O_CREAT | O_TRUNC | O_BINARY,
                                 0666);
@@ -675,7 +680,9 @@ static void to_cache(ARGS *args)
                close(fd_cpp_stderr);
                close(fd_real_stderr);
                close(fd_result);
+               unlink(tmp_stderr2);
                unlink(cpp_stderr);
+               free(tmp_stderr2);
                free(cpp_stderr);
                cpp_stderr = NULL;
        }