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, 13 insertions, 17 deletions

diff --git a/src/readahead/readahead.c b/src/readahead/readahead.c
index 73cf53805..35176e937 100644
--- a/src/readahead/readahead.c
+++ b/src/readahead/readahead.c
@@ -36,31 +36,26 @@ unsigned arg_files_max = 16*1024;
 off_t arg_file_size_max = READAHEAD_FILE_SIZE_MAX;
 usec_t arg_timeout = 2*USEC_PER_MINUTE;
 
-static int help(void) {
-
-        printf("%s [OPTIONS...] collect [DIRECTORY]\n\n"
+static void help(void) {
+        printf("%1$s [OPTIONS...] collect [DIRECTORY]\n\n"
                "Collect read-ahead data on early boot.\n\n"
                "  -h --help                 Show this help\n"
                "     --version              Show package version\n"
                "     --files-max=INT        Maximum number of files to read ahead\n"
                "     --file-size-max=BYTES  Maximum size of files to read ahead\n"
-               "     --timeout=USEC         Maximum time to spend collecting data\n\n\n",
-               program_invocation_short_name);
-
-        printf("%s [OPTIONS...] replay [DIRECTORY]\n\n"
+               "     --timeout=USEC         Maximum time to spend collecting data\n"
+               "\n\n"
+               "%1$s [OPTIONS...] replay [DIRECTORY]\n\n"
                "Replay collected read-ahead data on early boot.\n\n"
                "  -h --help                 Show this help\n"
                "     --version              Show package version\n"
-               "     --file-size-max=BYTES  Maximum size of files to read ahead\n\n\n",
-               program_invocation_short_name);
-
-        printf("%s [OPTIONS...] analyze [PACK FILE]\n\n"
+               "     --file-size-max=BYTES  Maximum size of files to read ahead\n"
+               "\n\n"
+               "%1$s [OPTIONS...] analyze [PACK-FILE]\n\n"
                "Analyze collected read-ahead data.\n\n"
                "  -h --help                 Show this help\n"
                "     --version              Show package version\n",
                program_invocation_short_name);
-
-        return 0;
 }
 
 static int parse_argv(int argc, char *argv[]) {
@@ -86,12 +81,13 @@ static int parse_argv(int argc, char *argv[]) {
         assert(argc >= 0);
         assert(argv);
 
-        while ((c = getopt_long(argc, argv, "h", options, NULL)) >= 0) {
+        while ((c = getopt_long(argc, argv, "h", options, NULL)) >= 0)
 
                 switch (c) {
 
                 case 'h':
-                        return help();
+                        help();
+                        return 0;
 
                 case ARG_VERSION:
                         puts(PACKAGE_STRING);
@@ -131,11 +127,11 @@ static int parse_argv(int argc, char *argv[]) {
                 default:
                         assert_not_reached("Unhandled option");
                 }
-        }
 
         if (optind != argc-1 &&
             optind != argc-2) {
-                help();
+                log_error("%s: wrong number of arguments.",
+                          program_invocation_short_name);
                 return -EINVAL;
         }