From cd8854e622793b3f3e7104d29f06e614d4dfac42 Mon Sep 17 00:00:00 2001 From: Lorenz Meier Date: Fri, 20 Sep 2013 19:59:48 +0200 Subject: Hotfix: Make param saving relatively robust --- src/modules/systemlib/param/param.c | 38 +++++++++++++++++++++++++++++++------ 1 file changed, 32 insertions(+), 6 deletions(-) (limited to 'src/modules/systemlib') diff --git a/src/modules/systemlib/param/param.c b/src/modules/systemlib/param/param.c index 59cbcf5fb..ccdb2ea38 100644 --- a/src/modules/systemlib/param/param.c +++ b/src/modules/systemlib/param/param.c @@ -509,31 +509,57 @@ int param_save_default(void) { int result; + unsigned retries = 0; /* delete the file in case it exists */ struct stat buffer; if (stat(param_get_default_file(), &buffer) == 0) { - result = unlink(param_get_default_file()); + + do { + result = unlink(param_get_default_file()); + if (result != 0) { + retries++; + usleep(1000 * retries); + } + } while (result != OK && retries < 10); + if (result != OK) warnx("unlinking file %s failed.", param_get_default_file()); } /* create the file */ - int fd = open(param_get_default_file(), O_WRONLY | O_CREAT | O_EXCL); + int fd; - if (fd < 0) { + do { /* do another attempt in case the unlink call is not synced yet */ - usleep(5000); fd = open(param_get_default_file(), O_WRONLY | O_CREAT | O_EXCL); + if (fd < 0) { + retries++; + usleep(1000 * retries); + } + } while (fd < 0 && retries < 10); + + if (fd < 0) { + warn("opening '%s' for writing failed", param_get_default_file()); return fd; } - result = param_export(fd, false); + do { + result = param_export(fd, false); + + if (result != OK) { + retries++; + usleep(1000 * retries); + } + + } while (result != 0 && retries < 10); + + close(fd); - if (result != 0) { + if (result != OK) { warn("error exporting parameters to '%s'", param_get_default_file()); (void)unlink(param_get_default_file()); return result; -- cgit v1.2.3