Unify parse_argv style

getopt is usually good at printing out a nice error message when
commandline options are invalid. It distinguishes between an unknown
option and a known option with a missing arg. It is better to let it
do its job and not use opterr=0 unless we actually want to suppress
messages. So remove opterr=0 in the few places where it wasn't really
useful.

When an error in options is encountered, we should not print a lengthy
help() and overwhelm the user, when we know precisely what is wrong
with the commandline. In addition, since help() prints to stdout, it
should not be used except when requested with -h or --help.

Also, simplify things here and there.

1 files changed, 8 insertions, 10 deletions

diff --git a/src/detect-virt/detect-virt.c b/src/detect-virt/detect-virt.c
index 8cf8dcfabc..ff5bee56f9 100644
--- a/src/detect-virt/detect-virt.c
+++ b/src/detect-virt/detect-virt.c
@@ -36,18 +36,15 @@ static enum {
         ONLY_CONTAINER
 } arg_mode = ANY_VIRTUALIZATION;
 
-static int help(void) {
-
+static void help(void) {
         printf("%s [OPTIONS...]\n\n"
                "Detect execution in a virtualized environment.\n\n"
                "  -h --help             Show this help\n"
                "     --version          Show package version\n"
                "  -c --container        Only detect whether we are run in a container\n"
                "  -v --vm               Only detect whether we are run in a VM\n"
-               "  -q --quiet            Don't output anything, just set return value\n",
-               program_invocation_short_name);
-
-        return 0;
+               "  -q --quiet            Don't output anything, just set return value\n"
+               , program_invocation_short_name);
 }
 
 static int parse_argv(int argc, char *argv[]) {
@@ -70,12 +67,13 @@ static int parse_argv(int argc, char *argv[]) {
         assert(argc >= 0);
         assert(argv);
 
-        while ((c = getopt_long(argc, argv, "hqcv", options, NULL)) >= 0) {
+        while ((c = getopt_long(argc, argv, "hqcv", options, NULL)) >= 0)
 
                 switch (c) {
 
                 case 'h':
-                        return help();
+                        help();
+                        return 0;
 
                 case ARG_VERSION:
                         puts(PACKAGE_STRING);
@@ -100,10 +98,10 @@ static int parse_argv(int argc, char *argv[]) {
                 default:
                         assert_not_reached("Unhandled option");
                 }
-        }
 
         if (optind < argc) {
-                help();
+                log_error("%s takes no arguments.",
+                          program_invocation_short_name);
                 return -EINVAL;
         }