main: use one data-structure to initialize getopt_long(3) arguments and help.

By generating the getopt_long(3) optstring and options, and the help
from one source, we reduce the chance that they may get out of sync.

Signed-off-by: Jeremy Sowden <jeremy@azazel.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

diff --git a/src/main.c b/src/main.c
index 4e9a2ed3bcec6df71a9904e7dee10254f5b8c671..1ee4d957a152c834a6f83777fa3ed6cdbe8edc90 100644 (file)
--- a/src/main.c
+++ b/src/main.c
@@ -24,6 +24,19 @@
 
 static struct nft_ctx *nft;
 
+/*
+ * These options are grouped separately in the help, so we give them named
+ * indices for use there.
+ */
+enum opt_indices {
+       IDX_HELP,
+       IDX_VERSION,
+       IDX_VERSION_LONG,
+       IDX_CHECK,
+       IDX_FILE,
+       IDX_INTERACTIVE,
+};
+
 enum opt_vals {
        OPT_HELP                = 'h',
        OPT_VERSION             = 'v',
@@ -47,123 +60,133 @@ enum opt_vals {
        OPT_TERSE               = 't',
        OPT_INVALID             = '?',
 };
-#define OPTSTRING      "+hvVcf:iI:jnsNSd:aeuypTt"
 
-static const struct option options[] = {
-       {
-               .name           = "help",
-               .val            = OPT_HELP,
-       },
-       {
-               .name           = "version",
-               .val            = OPT_VERSION,
-       },
-       {
-               .name           = "check",
-               .val            = OPT_CHECK,
-       },
-       {
-               .name           = "file",
-               .val            = OPT_FILE,
-               .has_arg        = 1,
-       },
-       {
-               .name           = "interactive",
-               .val            = OPT_INTERACTIVE,
-       },
-       {
-               .name           = "numeric",
-               .val            = OPT_NUMERIC,
-       },
-       {
-               .name           = "stateless",
-               .val            = OPT_STATELESS,
-       },
-       {
-               .name           = "reversedns",
-               .val            = OPT_IP2NAME,
-       },
-       {
-               .name           = "service",
-               .val            = OPT_SERVICE,
-       },
-       {
-               .name           = "includepath",
-               .val            = OPT_INCLUDEPATH,
-               .has_arg        = 1,
-       },
-       {
-               .name           = "debug",
-               .val            = OPT_DEBUG,
-               .has_arg        = 1,
-       },
-       {
-               .name           = "handle",
-               .val            = OPT_HANDLE_OUTPUT,
-       },
-       {
-               .name           = "echo",
-               .val            = OPT_ECHO,
-       },
-       {
-               .name           = "json",
-               .val            = OPT_JSON,
-       },
-       {
-               .name           = "guid",
-               .val            = OPT_GUID,
-       },
-       {
-               .name           = "numeric-priority",
-               .val            = OPT_NUMERIC_PRIO,
-       },
-       {
-               .name           = "numeric-protocol",
-               .val            = OPT_NUMERIC_PROTO,
-       },
-       {
-               .name           = "numeric-time",
-               .val            = OPT_NUMERIC_TIME,
-       },
-       {
-               .name           = "terse",
-               .val            = OPT_TERSE,
-       },
-       {
-               .name           = NULL
-       }
+struct nft_opt {
+       const char    *name;
+       enum opt_vals  val;
+       const char    *arg;
+       const char    *help;
+};
+
+#define NFT_OPT(n, v, a, h) \
+       (struct nft_opt) { .name = n, .val = v, .arg = a, .help = h }
+
+static const struct nft_opt nft_options[] = {
+       NFT_OPT("help",                 OPT_HELP,               NULL,
+               "Show this help"),
+       NFT_OPT("version",              OPT_VERSION,            NULL,
+               "Show version information"),
+       NFT_OPT(NULL,                   OPT_VERSION_LONG,       NULL,
+               "Show extended version information"),
+       NFT_OPT("check",                OPT_CHECK,              NULL,
+               "Check commands validity without actually applying the changes."),
+       NFT_OPT("file",                 OPT_FILE,               "<filename>",
+               "Read input from <filename>"),
+       NFT_OPT("interactive",          OPT_INTERACTIVE,        NULL,
+               "Read input from interactive CLI"),
+       NFT_OPT("numeric",              OPT_NUMERIC,            NULL,
+               "Print fully numerical output."),
+       NFT_OPT("stateless",            OPT_STATELESS,          NULL,
+               "Omit stateful information of ruleset."),
+       NFT_OPT("reversedns",           OPT_IP2NAME,            NULL,
+               "Translate IP addresses to names."),
+       NFT_OPT("service",              OPT_SERVICE,            NULL,
+               "Translate ports to service names as described in /etc/services."),
+       NFT_OPT("includepath",          OPT_INCLUDEPATH,        "<directory>",
+               "Add <directory> to the paths searched for include files. Default is: " DEFAULT_INCLUDE_PATH),
+       NFT_OPT("debug",                OPT_DEBUG,              "<level [,level...]>",
+               "Specify debugging level (scanner, parser, eval, netlink, mnl, proto-ctx, segtree, all)"),
+       NFT_OPT("handle",               OPT_HANDLE_OUTPUT,      NULL,
+               "Output rule handle."),
+       NFT_OPT("echo",                 OPT_ECHO,               NULL,
+               "Echo what has been added, inserted or replaced."),
+       NFT_OPT("json",                 OPT_JSON,               NULL,
+               "Format output in JSON"),
+       NFT_OPT("guid",                 OPT_GUID,               NULL,
+               "Print UID/GID as defined in /etc/passwd and /etc/group."),
+       NFT_OPT("numeric-priority",     OPT_NUMERIC_PRIO,       NULL,
+               "Print chain priority numerically."),
+       NFT_OPT("numeric-protocol",     OPT_NUMERIC_PROTO,      NULL,
+               "Print layer 4 protocols numerically."),
+       NFT_OPT("numeric-time",         OPT_NUMERIC_TIME,       NULL,
+               "Print time values numerically."),
+       NFT_OPT("terse",                OPT_TERSE,              NULL,
+               "Omit contents of sets."),
 };
 
+#define NR_NFT_OPTIONS (sizeof(nft_options) / sizeof(nft_options[0]))
+
+static const char *get_optstring(void)
+{
+       static char optstring[NR_NFT_OPTIONS + 2];
+
+       if (!optstring[0]) {
+               size_t i, j;
+
+               optstring[0] = '+';
+               for (i = 0, j = 1; i < NR_NFT_OPTIONS; i++)
+                       j += sprintf(optstring + j, "%c%s",
+                                    nft_options[i].val,
+                                    nft_options[i].arg ? ":" : "");
+       }
+       return optstring;
+}
+
+static const struct option *get_options(void)
+{
+       static struct option options[NR_NFT_OPTIONS + 1];
+
+       if (!options[0].name) {
+               size_t i, j;
+
+               for (i = 0, j = 0; i < NR_NFT_OPTIONS; ++i) {
+                       if (nft_options[i].name) {
+                               options[j].name    = nft_options[i].name;
+                               options[j].val     = nft_options[i].val;
+                               options[j].has_arg = nft_options[i].arg != NULL;
+                               j++;
+                       }
+               }
+       }
+       return options;
+}
+
+static void print_option(const struct nft_opt *opt)
+{
+       char optbuf[33] = "";
+       int i;
+
+       i = snprintf(optbuf, sizeof(optbuf), "  -%c", opt->val);
+       if (opt->name)
+               i += snprintf(optbuf + i, sizeof(optbuf) - i, ", %s", opt->name);
+       if (opt->arg)
+               i += snprintf(optbuf + i, sizeof(optbuf) - i, " %s", opt->arg);
+
+       printf("%-32s%s\n", optbuf, opt->help);
+}
+
 static void show_help(const char *name)
 {
-       printf(
-"Usage: %s [ options ] [ cmds... ]\n"
-"\n"
-"Options:\n"
-"  -h, --help                          Show this help\n"
-"  -v, --version                               Show version information\n"
-"  -V                                  Show extended version information\n"
-"\n"
-"  -c, --check                         Check commands validity without actually applying the changes.\n"
-"  -f, --file <filename>                       Read input from <filename>\n"
-"  -i, --interactive                   Read input from interactive CLI\n"
-"\n"
-"  -j, --json                          Format output in JSON\n"
-"  -n, --numeric                               Print fully numerical output.\n"
-"  -s, --stateless                     Omit stateful information of ruleset.\n"
-"  -t, --terse                         Omit contents of sets.\n"
-"  -u, --guid                          Print UID/GID as defined in /etc/passwd and /etc/group.\n"
-"  -N, --reversedns                    Translate IP addresses to names.\n"
-"  -S, --service                               Translate ports to service names as described in /etc/services.\n"
-"  -p, --numeric-protocol              Print layer 4 protocols numerically.\n"
-"  -y, --numeric-priority              Print chain priority numerically.\n"
-"  -T, --numeric-time                  Print time values numerically.\n"
-"  -a, --handle                                Output rule handle.\n"
-"  -e, --echo                          Echo what has been added, inserted or replaced.\n"
-"  -I, --includepath <directory>               Add <directory> to the paths searched for include files. Default is: " DEFAULT_INCLUDE_PATH "\n"
-"  -d, --debug <level [,level...]>     Specify debugging level (scanner, parser, eval, netlink, mnl, proto-ctx, segtree, all)\n"
-"\n",
-       name);
+       printf("Usage: %s [ options ] [ cmds... ]\n"
+              "\n"
+              "Options:\n", name);
+
+       print_option(&nft_options[IDX_HELP]);
+       print_option(&nft_options[IDX_VERSION]);
+       print_option(&nft_options[IDX_VERSION_LONG]);
+
+       fputs("\n", stdout);
+
+       print_option(&nft_options[IDX_CHECK]);
+       print_option(&nft_options[IDX_FILE]);
+       print_option(&nft_options[IDX_INTERACTIVE]);
+
+       fputs("\n", stdout);
+
+       for (size_t i = IDX_INTERACTIVE + 1; i < NR_NFT_OPTIONS; ++i)
+               print_option(&nft_options[i]);
+
+       fputs("\n", stdout);
 }
 
 static void show_version(void)
@@ -288,6 +311,8 @@ static bool nft_options_check(int argc, char * const argv[])
 
 int main(int argc, char * const *argv)
 {
+       const struct option *options = get_options();
+       const char *optstring = get_optstring();
        char *buf = NULL, *filename = NULL;
        unsigned int output_flags = 0;
        bool interactive = false;
@@ -301,7 +326,7 @@ int main(int argc, char * const *argv)
        nft = nft_ctx_new(NFT_CTX_DEFAULT);
 
        while (1) {
-               val = getopt_long(argc, argv, OPTSTRING, options, NULL);
+               val = getopt_long(argc, argv, optstring, options, NULL);
                if (val == -1)
                        break;