From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([208.118.235.92]:44165) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1T4xB0-0006kD-01 for qemu-devel@nongnu.org; Fri, 24 Aug 2012 12:56:11 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1T4xAx-00037e-VK for qemu-devel@nongnu.org; Fri, 24 Aug 2012 12:56:05 -0400 Received: from mnementh.archaic.org.uk ([81.2.115.146]:54367) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1T4xAx-0002wi-Nl for qemu-devel@nongnu.org; Fri, 24 Aug 2012 12:56:03 -0400 From: Peter Maydell Date: Fri, 24 Aug 2012 17:55:53 +0100 Message-Id: <1345827353-17112-1-git-send-email-peter.maydell@linaro.org> Subject: [Qemu-devel] [PATCH] linux-user: If loading fails, print error as string, not number List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: Christophe Lyon , Riku Voipio , patches@linaro.org If the attempt to load the guest executable fails, print the error message as a string, not a number. This requires us to fix a couple of places in loader_exec() where we were returning -1 instead of a valid negative errno. The change allows us to drop the "Unknown binary format" message because the strerror-enhanced message is now a more self-explanatory "Error while loading $guest-binary: Exec format error". Signed-off-by: Peter Maydell --- My motivation here was that "user downloads guest binary from somewhere and it ends up without exec permissions" is quite a common mistake, and "Error -13 while loading my-program" is not a very helpful way to report this... linux-user/linuxload.c | 8 ++++---- linux-user/main.c | 2 +- 2 files changed, 5 insertions(+), 5 deletions(-) diff --git a/linux-user/linuxload.c b/linux-user/linuxload.c index b47025f..381ab89 100644 --- a/linux-user/linuxload.c +++ b/linux-user/linuxload.c @@ -140,8 +140,9 @@ int loader_exec(const char * filename, char ** argv, char ** envp, bprm->p = TARGET_PAGE_SIZE*MAX_ARG_PAGES-sizeof(unsigned int); memset(bprm->page, 0, sizeof(bprm->page)); retval = open(filename, O_RDONLY); - if (retval < 0) - return retval; + if (retval < 0) { + return -errno; + } bprm->fd = retval; bprm->filename = (char *)filename; bprm->argc = count(argv); @@ -165,8 +166,7 @@ int loader_exec(const char * filename, char ** argv, char ** envp, retval = load_flt_binary(bprm,regs,infop); #endif } else { - fprintf(stderr, "Unknown binary format\n"); - return -1; + return -ENOEXEC; } } diff --git a/linux-user/main.c b/linux-user/main.c index 7dea084..ae0de9a 100644 --- a/linux-user/main.c +++ b/linux-user/main.c @@ -3581,7 +3581,7 @@ int main(int argc, char **argv, char **envp) ret = loader_exec(filename, target_argv, target_environ, regs, info, &bprm); if (ret != 0) { - printf("Error %d while loading %s\n", ret, filename); + printf("Error while loading %s: %s\n", filename, strerror(-ret)); _exit(1); } -- 1.7.9.5