From b276d2499428795629eee8ee93ba1ea100bb1bc9 Mon Sep 17 00:00:00 2001 From: Max Reitz Date: Thu, 7 Nov 2013 20:10:29 +0100 Subject: [PATCH] util/error: Save errno from clobbering There may be calls to error_setg() and especially error_setg_errno() which blindly (and until now wrongly) assume these functions not to clobber errno (e.g., they pass errno to error_setg_errno() and return -errno afterwards). Instead of trying to find and fix all of these constructs, just make sure error_setg() and error_setg_errno() indeed do not clobber errno. Suggested-by: Eric Blake Signed-off-by: Max Reitz Reviewed-by: Benoit Canet Signed-off-by: Stefan Hajnoczi --- util/error.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/util/error.c b/util/error.c index ec0faa6176..3ee362a7f5 100644 --- a/util/error.c +++ b/util/error.c @@ -27,6 +27,7 @@ void error_set(Error **errp, ErrorClass err_class, const char *fmt, ...) { Error *err; va_list ap; + int saved_errno = errno; if (errp == NULL) { return; @@ -41,6 +42,8 @@ void error_set(Error **errp, ErrorClass err_class, const char *fmt, ...) err->err_class = err_class; *errp = err; + + errno = saved_errno; } void error_set_errno(Error **errp, int os_errno, ErrorClass err_class, @@ -49,6 +52,7 @@ void error_set_errno(Error **errp, int os_errno, ErrorClass err_class, Error *err; char *msg1; va_list ap; + int saved_errno = errno; if (errp == NULL) { return; @@ -69,6 +73,8 @@ void error_set_errno(Error **errp, int os_errno, ErrorClass err_class, err->err_class = err_class; *errp = err; + + errno = saved_errno; } void error_setg_file_open(Error **errp, int os_errno, const char *filename)