iptables: remove duplicated argument parsing code

1. Factor out repeated code to a new xs_has_arg function.
2. Add a new parse_wait_time option to parse the value of -w.
3. Make parse_wait_interval take argc and argv so its callers
   can be simpler.

Signed-off-by: Lorenzo Colitti <lorenzo@google.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

diff --git a/iptables/ip6tables.c b/iptables/ip6tables.c
index 0bd415dec56f1f8cb3a4950ed12d788315f5df65..4d77721b0473b0d3c8815a0df7fceb52faee7697 100644 (file)
--- a/iptables/ip6tables.c
+++ b/iptables/ip6tables.c
@@ -1400,8 +1400,7 @@ int do_command6(int argc, char *argv[], char **table,
                        add_command(&command, CMD_DELETE, CMD_NONE,
                                    cs.invert);
                        chain = optarg;
-                       if (optind < argc && argv[optind][0] != '-'
-                           && argv[optind][0] != '!') {
+                       if (xs_has_arg(argc, argv)) {
                                rulenum = parse_rulenumber(argv[optind++]);
                                command = CMD_DELETE_NUM;
                        }
@@ -1411,8 +1410,7 @@ int do_command6(int argc, char *argv[], char **table,
                        add_command(&command, CMD_REPLACE, CMD_NONE,
                                    cs.invert);
                        chain = optarg;
-                       if (optind < argc && argv[optind][0] != '-'
-                           && argv[optind][0] != '!')
+                       if (xs_has_arg(argc, argv))
                                rulenum = parse_rulenumber(argv[optind++]);
                        else
                                xtables_error(PARAMETER_PROBLEM,
@@ -1424,8 +1422,7 @@ int do_command6(int argc, char *argv[], char **table,
                        add_command(&command, CMD_INSERT, CMD_NONE,
                                    cs.invert);
                        chain = optarg;
-                       if (optind < argc && argv[optind][0] != '-'
-                           && argv[optind][0] != '!')
+                       if (xs_has_arg(argc, argv))
                                rulenum = parse_rulenumber(argv[optind++]);
                        else rulenum = 1;
                        break;
@@ -1434,11 +1431,9 @@ int do_command6(int argc, char *argv[], char **table,
                        add_command(&command, CMD_LIST,
                                    CMD_ZERO | CMD_ZERO_NUM, cs.invert);
                        if (optarg) chain = optarg;
-                       else if (optind < argc && argv[optind][0] != '-'
-                                && argv[optind][0] != '!')
+                       else if (xs_has_arg(argc, argv))
                                chain = argv[optind++];
-                       if (optind < argc && argv[optind][0] != '-'
-                           && argv[optind][0] != '!')
+                       if (xs_has_arg(argc, argv))
                                rulenum = parse_rulenumber(argv[optind++]);
                        break;
 
@@ -1446,11 +1441,9 @@ int do_command6(int argc, char *argv[], char **table,
                        add_command(&command, CMD_LIST_RULES,
                                    CMD_ZERO | CMD_ZERO_NUM, cs.invert);
                        if (optarg) chain = optarg;
-                       else if (optind < argc && argv[optind][0] != '-'
-                                && argv[optind][0] != '!')
+                       else if (xs_has_arg(argc, argv))
                                chain = argv[optind++];
-                       if (optind < argc && argv[optind][0] != '-'
-                           && argv[optind][0] != '!')
+                       if (xs_has_arg(argc, argv))
                                rulenum = parse_rulenumber(argv[optind++]);
                        break;
 
@@ -1458,8 +1451,7 @@ int do_command6(int argc, char *argv[], char **table,
                        add_command(&command, CMD_FLUSH, CMD_NONE,
                                    cs.invert);
                        if (optarg) chain = optarg;
-                       else if (optind < argc && argv[optind][0] != '-'
-                                && argv[optind][0] != '!')
+                       else if (xs_has_arg(argc, argv))
                                chain = argv[optind++];
                        break;
 
@@ -1467,11 +1459,9 @@ int do_command6(int argc, char *argv[], char **table,
                        add_command(&command, CMD_ZERO, CMD_LIST|CMD_LIST_RULES,
                                    cs.invert);
                        if (optarg) chain = optarg;
-                       else if (optind < argc && argv[optind][0] != '-'
-                               && argv[optind][0] != '!')
+                       else if (xs_has_arg(argc, argv))
                                chain = argv[optind++];
-                       if (optind < argc && argv[optind][0] != '-'
-                               && argv[optind][0] != '!') {
+                       if (xs_has_arg(argc, argv)) {
                                rulenum = parse_rulenumber(argv[optind++]);
                                command = CMD_ZERO_NUM;
                        }
@@ -1488,8 +1478,7 @@ int do_command6(int argc, char *argv[], char **table,
                        add_command(&command, CMD_DELETE_CHAIN, CMD_NONE,
                                    cs.invert);
                        if (optarg) chain = optarg;
-                       else if (optind < argc && argv[optind][0] != '-'
-                                && argv[optind][0] != '!')
+                       else if (xs_has_arg(argc, argv))
                                chain = argv[optind++];
                        break;
 
@@ -1497,8 +1486,7 @@ int do_command6(int argc, char *argv[], char **table,
                        add_command(&command, CMD_RENAME_CHAIN, CMD_NONE,
                                    cs.invert);
                        chain = optarg;
-                       if (optind < argc && argv[optind][0] != '-'
-                           && argv[optind][0] != '!')
+                       if (xs_has_arg(argc, argv))
                                newname = argv[optind++];
                        else
                                xtables_error(PARAMETER_PROBLEM,
@@ -1511,8 +1499,7 @@ int do_command6(int argc, char *argv[], char **table,
                        add_command(&command, CMD_SET_POLICY, CMD_NONE,
                                    cs.invert);
                        chain = optarg;
-                       if (optind < argc && argv[optind][0] != '-'
-                           && argv[optind][0] != '!')
+                       if (xs_has_arg(argc, argv))
                                policy = argv[optind++];
                        else
                                xtables_error(PARAMETER_PROBLEM,
@@ -1622,16 +1609,7 @@ int do_command6(int argc, char *argv[], char **table,
                                              "You cannot use `-w' from "
                                              "ip6tables-restore");
                        }
-                       wait = -1;
-                       if (optarg) {
-                               if (sscanf(optarg, "%i", &wait) != 1)
-                                       xtables_error(PARAMETER_PROBLEM,
-                                               "wait seconds not numeric");
-                       } else if (optind < argc && argv[optind][0] != '-'
-                                                && argv[optind][0] != '!')
-                               if (sscanf(argv[optind++], "%i", &wait) != 1)
-                                       xtables_error(PARAMETER_PROBLEM,
-                                               "wait seconds not numeric");
+                       wait = parse_wait_time(argc, argv);
                        break;
 
                case 'W':
@@ -1640,14 +1618,7 @@ int do_command6(int argc, char *argv[], char **table,
                                              "You cannot use `-W' from "
                                              "ip6tables-restore");
                        }
-                       if (optarg)
-                               parse_wait_interval(optarg, &wait_interval);
-                       else if (optind < argc &&
-                               argv[optind][0] != '-' &&
-                               argv[optind][0] != '!')
-                               parse_wait_interval(argv[optind++],
-                                                   &wait_interval);
-
+                       parse_wait_interval(argc, argv, &wait_interval);
                        wait_interval_set = true;
                        break;
 
@@ -1697,8 +1668,7 @@ int do_command6(int argc, char *argv[], char **table,
                        bcnt = strchr(pcnt + 1, ',');
                        if (bcnt)
                            bcnt++;
-                       if (!bcnt && optind < argc && argv[optind][0] != '-'
-                           && argv[optind][0] != '!')
+                       if (!bcnt && xs_has_arg(argc, argv))
                                bcnt = argv[optind++];
                        if (!bcnt)
                                xtables_error(PARAMETER_PROBLEM,

diff --git a/iptables/iptables.c b/iptables/iptables.c
index e0d092f0b69bfa1349f88bb91dead8d3c51fbabd..04be5abb10c500d9944d85d34e27616be1e7b434 100644 (file)
--- a/iptables/iptables.c
+++ b/iptables/iptables.c
@@ -1393,8 +1393,7 @@ int do_command4(int argc, char *argv[], char **table,
                        add_command(&command, CMD_DELETE, CMD_NONE,
                                    cs.invert);
                        chain = optarg;
-                       if (optind < argc && argv[optind][0] != '-'
-                           && argv[optind][0] != '!') {
+                       if (xs_has_arg(argc, argv)) {
                                rulenum = parse_rulenumber(argv[optind++]);
                                command = CMD_DELETE_NUM;
                        }
@@ -1404,8 +1403,7 @@ int do_command4(int argc, char *argv[], char **table,
                        add_command(&command, CMD_REPLACE, CMD_NONE,
                                    cs.invert);
                        chain = optarg;
-                       if (optind < argc && argv[optind][0] != '-'
-                           && argv[optind][0] != '!')
+                       if (xs_has_arg(argc, argv))
                                rulenum = parse_rulenumber(argv[optind++]);
                        else
                                xtables_error(PARAMETER_PROBLEM,
@@ -1417,8 +1415,7 @@ int do_command4(int argc, char *argv[], char **table,
                        add_command(&command, CMD_INSERT, CMD_NONE,
                                    cs.invert);
                        chain = optarg;
-                       if (optind < argc && argv[optind][0] != '-'
-                           && argv[optind][0] != '!')
+                       if (xs_has_arg(argc, argv))
                                rulenum = parse_rulenumber(argv[optind++]);
                        else rulenum = 1;
                        break;
@@ -1427,11 +1424,9 @@ int do_command4(int argc, char *argv[], char **table,
                        add_command(&command, CMD_LIST,
                                    CMD_ZERO | CMD_ZERO_NUM, cs.invert);
                        if (optarg) chain = optarg;
-                       else if (optind < argc && argv[optind][0] != '-'
-                                && argv[optind][0] != '!')
+                       else if (xs_has_arg(argc, argv))
                                chain = argv[optind++];
-                       if (optind < argc && argv[optind][0] != '-'
-                           && argv[optind][0] != '!')
+                       if (xs_has_arg(argc, argv))
                                rulenum = parse_rulenumber(argv[optind++]);
                        break;
 
@@ -1439,11 +1434,9 @@ int do_command4(int argc, char *argv[], char **table,
                        add_command(&command, CMD_LIST_RULES,
                                    CMD_ZERO|CMD_ZERO_NUM, cs.invert);
                        if (optarg) chain = optarg;
-                       else if (optind < argc && argv[optind][0] != '-'
-                                && argv[optind][0] != '!')
+                       else if (xs_has_arg(argc, argv))
                                chain = argv[optind++];
-                       if (optind < argc && argv[optind][0] != '-'
-                           && argv[optind][0] != '!')
+                       if (xs_has_arg(argc, argv))
                                rulenum = parse_rulenumber(argv[optind++]);
                        break;
 
@@ -1451,8 +1444,7 @@ int do_command4(int argc, char *argv[], char **table,
                        add_command(&command, CMD_FLUSH, CMD_NONE,
                                    cs.invert);
                        if (optarg) chain = optarg;
-                       else if (optind < argc && argv[optind][0] != '-'
-                                && argv[optind][0] != '!')
+                       else if (xs_has_arg(argc, argv))
                                chain = argv[optind++];
                        break;
 
@@ -1460,11 +1452,9 @@ int do_command4(int argc, char *argv[], char **table,
                        add_command(&command, CMD_ZERO, CMD_LIST|CMD_LIST_RULES,
                                    cs.invert);
                        if (optarg) chain = optarg;
-                       else if (optind < argc && argv[optind][0] != '-'
-                               && argv[optind][0] != '!')
+                       else if (xs_has_arg(argc, argv))
                                chain = argv[optind++];
-                       if (optind < argc && argv[optind][0] != '-'
-                               && argv[optind][0] != '!') {
+                       if (xs_has_arg(argc, argv)) {
                                rulenum = parse_rulenumber(argv[optind++]);
                                command = CMD_ZERO_NUM;
                        }
@@ -1481,8 +1471,7 @@ int do_command4(int argc, char *argv[], char **table,
                        add_command(&command, CMD_DELETE_CHAIN, CMD_NONE,
                                    cs.invert);
                        if (optarg) chain = optarg;
-                       else if (optind < argc && argv[optind][0] != '-'
-                                && argv[optind][0] != '!')
+                       else if (xs_has_arg(argc, argv))
                                chain = argv[optind++];
                        break;
 
@@ -1490,8 +1479,7 @@ int do_command4(int argc, char *argv[], char **table,
                        add_command(&command, CMD_RENAME_CHAIN, CMD_NONE,
                                    cs.invert);
                        chain = optarg;
-                       if (optind < argc && argv[optind][0] != '-'
-                           && argv[optind][0] != '!')
+                       if (xs_has_arg(argc, argv))
                                newname = argv[optind++];
                        else
                                xtables_error(PARAMETER_PROBLEM,
@@ -1504,8 +1492,7 @@ int do_command4(int argc, char *argv[], char **table,
                        add_command(&command, CMD_SET_POLICY, CMD_NONE,
                                    cs.invert);
                        chain = optarg;
-                       if (optind < argc && argv[optind][0] != '-'
-                           && argv[optind][0] != '!')
+                       if (xs_has_arg(argc, argv))
                                policy = argv[optind++];
                        else
                                xtables_error(PARAMETER_PROBLEM,
@@ -1613,16 +1600,7 @@ int do_command4(int argc, char *argv[], char **table,
                                              "You cannot use `-w' from "
                                              "iptables-restore");
                        }
-                       wait = -1;
-                       if (optarg) {
-                               if (sscanf(optarg, "%i", &wait) != 1)
-                                       xtables_error(PARAMETER_PROBLEM,
-                                               "wait seconds not numeric");
-                       } else if (optind < argc && argv[optind][0] != '-'
-                                                && argv[optind][0] != '!')
-                               if (sscanf(argv[optind++], "%i", &wait) != 1)
-                                       xtables_error(PARAMETER_PROBLEM,
-                                               "wait seconds not numeric");
+                       wait = parse_wait_time(argc, argv);
                        break;
 
                case 'W':
@@ -1631,14 +1609,7 @@ int do_command4(int argc, char *argv[], char **table,
                                              "You cannot use `-W' from "
                                              "iptables-restore");
                        }
-                       if (optarg)
-                               parse_wait_interval(optarg, &wait_interval);
-                       else if (optind < argc &&
-                                argv[optind][0] != '-' &&
-                                argv[optind][0] != '!')
-                               parse_wait_interval(argv[optind++],
-                                                   &wait_interval);
-
+                       parse_wait_interval(argc, argv, &wait_interval);
                        wait_interval_set = true;
                        break;
 
@@ -1688,8 +1659,7 @@ int do_command4(int argc, char *argv[], char **table,
                        bcnt = strchr(pcnt + 1, ',');
                        if (bcnt)
                            bcnt++;
-                       if (!bcnt && optind < argc && argv[optind][0] != '-'
-                           && argv[optind][0] != '!')
+                       if (!bcnt && xs_has_arg(argc, argv))
                                bcnt = argv[optind++];
                        if (!bcnt)
                                xtables_error(PARAMETER_PROBLEM,

diff --git a/iptables/xshared.c b/iptables/xshared.c
index 9b8e856e25d828811033e5fa2d0227d8bd36f7c1..06147d180a6487818bd21ec3d7064ee7f5a0e7c5 100644 (file)
--- a/iptables/xshared.c
+++ b/iptables/xshared.c
@@ -285,12 +285,36 @@ bool xtables_lock(int wait, struct timeval *wait_interval)
        }
 }
 
-void parse_wait_interval(const char *str, struct timeval *wait_interval)
+int parse_wait_time(int argc, char *argv[])
 {
+       int wait = -1;
+
+       if (optarg) {
+               if (sscanf(optarg, "%i", &wait) != 1)
+                       xtables_error(PARAMETER_PROBLEM,
+                               "wait seconds not numeric");
+       } else if (xs_has_arg(argc, argv))
+               if (sscanf(argv[optind++], "%i", &wait) != 1)
+                       xtables_error(PARAMETER_PROBLEM,
+                               "wait seconds not numeric");
+
+       return wait;
+}
+
+void parse_wait_interval(int argc, char *argv[], struct timeval *wait_interval)
+{
+       const char *arg;
        unsigned int usec;
        int ret;
 
-       ret = sscanf(str, "%u", &usec);
+       if (optarg)
+               arg = optarg;
+       else if (xs_has_arg(argc, argv))
+               arg = argv[optind++];
+       else
+               return;
+
+       ret = sscanf(arg, "%u", &usec);
        if (ret == 1) {
                if (usec > 999999)
                        xtables_error(PARAMETER_PROBLEM,
@@ -303,3 +327,10 @@ void parse_wait_interval(const char *str, struct timeval *wait_interval)
        }
        xtables_error(PARAMETER_PROBLEM, "wait interval not numeric");
 }
+
+inline bool xs_has_arg(int argc, char *argv[])
+{
+       return optind < argc &&
+              argv[optind][0] != '-' &&
+              argv[optind][0] != '!';
+}

diff --git a/iptables/xshared.h b/iptables/xshared.h
index 18b1cf37644b0e20dd5ae60c4092576aa6b9a46c..d8a697ae665dd91e1a7bf14dcacfa5a5e097a222 100644 (file)
--- a/iptables/xshared.h
+++ b/iptables/xshared.h
@@ -88,7 +88,9 @@ extern void xs_init_target(struct xtables_target *);
 extern void xs_init_match(struct xtables_match *);
 bool xtables_lock(int wait, struct timeval *wait_interval);
 
-void parse_wait_interval(const char *str, struct timeval *wait_interval);
+int parse_wait_time(int argc, char *argv[]);
+void parse_wait_interval(int argc, char *argv[], struct timeval *wait_interval);
+bool xs_has_arg(int argc, char *argv[]);
 
 extern const struct xtables_afinfo *afinfo;
 

diff --git a/iptables/xtables-arp.c b/iptables/xtables-arp.c
index bd6d57c2d892f76c6268f799783fcfade43f15e6..6aa000a14d266c64a5017ff53e1e1b49a3fdfc47 100644 (file)
--- a/iptables/xtables-arp.c
+++ b/iptables/xtables-arp.c
@@ -984,8 +984,7 @@ int do_commandarp(struct nft_handle *h, int argc, char *argv[], char **table)
                        add_command(&command, CMD_DELETE, CMD_NONE,
                                    invert);
                        chain = optarg;
-                       if (optind < argc && argv[optind][0] != '-'
-                           && argv[optind][0] != '!') {
+                       if (xs_has_arg(argc, argv)) {
                                rulenum = parse_rulenumber(argv[optind++]);
                                command = CMD_DELETE_NUM;
                        }
@@ -995,8 +994,7 @@ int do_commandarp(struct nft_handle *h, int argc, char *argv[], char **table)
                        add_command(&command, CMD_REPLACE, CMD_NONE,
                                    invert);
                        chain = optarg;
-                       if (optind < argc && argv[optind][0] != '-'
-                           && argv[optind][0] != '!')
+                       if (xs_has_arg(argc, argv))
                                rulenum = parse_rulenumber(argv[optind++]);
                        else
                                xtables_error(PARAMETER_PROBLEM,
@@ -1008,8 +1006,7 @@ int do_commandarp(struct nft_handle *h, int argc, char *argv[], char **table)
                        add_command(&command, CMD_INSERT, CMD_NONE,
                                    invert);
                        chain = optarg;
-                       if (optind < argc && argv[optind][0] != '-'
-                           && argv[optind][0] != '!')
+                       if (xs_has_arg(argc, argv))
                                rulenum = parse_rulenumber(argv[optind++]);
                        else rulenum = 1;
                        break;
@@ -1018,8 +1015,7 @@ int do_commandarp(struct nft_handle *h, int argc, char *argv[], char **table)
                        add_command(&command, CMD_LIST, CMD_ZERO,
                                    invert);
                        if (optarg) chain = optarg;
-                       else if (optind < argc && argv[optind][0] != '-'
-                                && argv[optind][0] != '!')
+                       else if (xs_has_arg(argc, argv))
                                chain = argv[optind++];
                        break;
 
@@ -1027,8 +1023,7 @@ int do_commandarp(struct nft_handle *h, int argc, char *argv[], char **table)
                        add_command(&command, CMD_FLUSH, CMD_NONE,
                                    invert);
                        if (optarg) chain = optarg;
-                       else if (optind < argc && argv[optind][0] != '-'
-                                && argv[optind][0] != '!')
+                       else if (xs_has_arg(argc, argv))
                                chain = argv[optind++];
                        break;
 
@@ -1036,8 +1031,7 @@ int do_commandarp(struct nft_handle *h, int argc, char *argv[], char **table)
                        add_command(&command, CMD_ZERO, CMD_LIST,
                                    invert);
                        if (optarg) chain = optarg;
-                       else if (optind < argc && argv[optind][0] != '-'
-                               && argv[optind][0] != '!')
+                       else if (xs_has_arg(argc, argv))
                                chain = argv[optind++];
                        break;
 
@@ -1059,8 +1053,7 @@ int do_commandarp(struct nft_handle *h, int argc, char *argv[], char **table)
                        add_command(&command, CMD_DELETE_CHAIN, CMD_NONE,
                                    invert);
                        if (optarg) chain = optarg;
-                       else if (optind < argc && argv[optind][0] != '-'
-                                && argv[optind][0] != '!')
+                       else if (xs_has_arg(argc, argv))
                                chain = argv[optind++];
                        break;
 
@@ -1068,8 +1061,7 @@ int do_commandarp(struct nft_handle *h, int argc, char *argv[], char **table)
                        add_command(&command, CMD_RENAME_CHAIN, CMD_NONE,
                                    invert);
                        chain = optarg;
-                       if (optind < argc && argv[optind][0] != '-'
-                           && argv[optind][0] != '!')
+                       if (xs_has_arg(argc, argv))
                                newname = argv[optind++];
                        else
                                xtables_error(PARAMETER_PROBLEM,
@@ -1082,8 +1074,7 @@ int do_commandarp(struct nft_handle *h, int argc, char *argv[], char **table)
                        add_command(&command, CMD_SET_POLICY, CMD_NONE,
                                    invert);
                        chain = optarg;
-                       if (optind < argc && argv[optind][0] != '-'
-                           && argv[optind][0] != '!')
+                       if (xs_has_arg(argc, argv))
                                policy = argv[optind++];
                        else
                                xtables_error(PARAMETER_PROBLEM,
@@ -1286,8 +1277,7 @@ int do_commandarp(struct nft_handle *h, int argc, char *argv[], char **table)
                        set_option(&options, OPT_COUNTERS, &cs.fw.arp.invflags,
                                   invert);
                        pcnt = optarg;
-                       if (optind < argc && argv[optind][0] != '-'
-                           && argv[optind][0] != '!')
+                       if (xs_has_arg(argc, argv))
                                bcnt = argv[optind++];
                        else
                                xtables_error(PARAMETER_PROBLEM,

diff --git a/iptables/xtables.c b/iptables/xtables.c
index d222ae991dc8536f57d81fc6df4bb41ead84a787..286866f75d933ab92d579aad8f917061f67aba20 100644 (file)
--- a/iptables/xtables.c
+++ b/iptables/xtables.c
@@ -744,8 +744,7 @@ void do_parse(struct nft_handle *h, int argc, char *argv[],
                        add_command(&p->command, CMD_DELETE, CMD_NONE,
                                    cs->invert);
                        p->chain = optarg;
-                       if (optind < argc && argv[optind][0] != '-'
-                           && argv[optind][0] != '!') {
+                       if (xs_has_arg(argc, argv)) {
                                p->rulenum = parse_rulenumber(argv[optind++]);
                                p->command = CMD_DELETE_NUM;
                        }
@@ -755,8 +754,7 @@ void do_parse(struct nft_handle *h, int argc, char *argv[],
                        add_command(&p->command, CMD_REPLACE, CMD_NONE,
                                    cs->invert);
                        p->chain = optarg;
-                       if (optind < argc && argv[optind][0] != '-'
-                           && argv[optind][0] != '!')
+                       if (xs_has_arg(argc, argv))
                                p->rulenum = parse_rulenumber(argv[optind++]);
                        else
                                xtables_error(PARAMETER_PROBLEM,
@@ -768,8 +766,7 @@ void do_parse(struct nft_handle *h, int argc, char *argv[],
                        add_command(&p->command, CMD_INSERT, CMD_NONE,
                                    cs->invert);
                        p->chain = optarg;
-                       if (optind < argc && argv[optind][0] != '-'
-                           && argv[optind][0] != '!')
+                       if (xs_has_arg(argc, argv))
                                p->rulenum = parse_rulenumber(argv[optind++]);
                        else
                                p->rulenum = 1;
@@ -780,11 +777,9 @@ void do_parse(struct nft_handle *h, int argc, char *argv[],
                                    CMD_ZERO | CMD_ZERO_NUM, cs->invert);
                        if (optarg)
                                p->chain = optarg;
-                       else if (optind < argc && argv[optind][0] != '-'
-                                && argv[optind][0] != '!')
+                       else if (xs_has_arg(argc, argv))
                                p->chain = argv[optind++];
-                       if (optind < argc && argv[optind][0] != '-'
-                           && argv[optind][0] != '!')
+                       if (xs_has_arg(argc, argv))
                                p->rulenum = parse_rulenumber(argv[optind++]);
                        break;
 
@@ -793,11 +788,9 @@ void do_parse(struct nft_handle *h, int argc, char *argv[],
                                    CMD_ZERO|CMD_ZERO_NUM, cs->invert);
                        if (optarg)
                                p->chain = optarg;
-                       else if (optind < argc && argv[optind][0] != '-'
-                                && argv[optind][0] != '!')
+                       else if (xs_has_arg(argc, argv))
                                p->chain = argv[optind++];
-                       if (optind < argc && argv[optind][0] != '-'
-                           && argv[optind][0] != '!')
+                       if (xs_has_arg(argc, argv))
                                p->rulenum = parse_rulenumber(argv[optind++]);
                        break;
 
@@ -806,8 +799,7 @@ void do_parse(struct nft_handle *h, int argc, char *argv[],
                                    cs->invert);
                        if (optarg)
                                p->chain = optarg;
-                       else if (optind < argc && argv[optind][0] != '-'
-                                && argv[optind][0] != '!')
+                       else if (xs_has_arg(argc, argv))
                                p->chain = argv[optind++];
                        break;
 
@@ -816,11 +808,9 @@ void do_parse(struct nft_handle *h, int argc, char *argv[],
                                    CMD_LIST|CMD_LIST_RULES, cs->invert);
                        if (optarg)
                                p->chain = optarg;
-                       else if (optind < argc && argv[optind][0] != '-'
-                               && argv[optind][0] != '!')
+                       else if (xs_has_arg(argc, argv))
                                p->chain = argv[optind++];
-                       if (optind < argc && argv[optind][0] != '-'
-                               && argv[optind][0] != '!') {
+                       if (xs_has_arg(argc, argv)) {
                                p->rulenum = parse_rulenumber(argv[optind++]);
                                p->command = CMD_ZERO_NUM;
                        }
@@ -845,8 +835,7 @@ void do_parse(struct nft_handle *h, int argc, char *argv[],
                                    cs->invert);
                        if (optarg)
                                p->chain = optarg;
-                       else if (optind < argc && argv[optind][0] != '-'
-                                && argv[optind][0] != '!')
+                       else if (xs_has_arg(argc, argv))
                                p->chain = argv[optind++];
                        break;
 
@@ -854,8 +843,7 @@ void do_parse(struct nft_handle *h, int argc, char *argv[],
                        add_command(&p->command, CMD_RENAME_CHAIN, CMD_NONE,
                                    cs->invert);
                        p->chain = optarg;
-                       if (optind < argc && argv[optind][0] != '-'
-                           && argv[optind][0] != '!')
+                       if (xs_has_arg(argc, argv))
                                p->newname = argv[optind++];
                        else
                                xtables_error(PARAMETER_PROBLEM,
@@ -868,8 +856,7 @@ void do_parse(struct nft_handle *h, int argc, char *argv[],
                        add_command(&p->command, CMD_SET_POLICY, CMD_NONE,
                                    cs->invert);
                        p->chain = optarg;
-                       if (optind < argc && argv[optind][0] != '-'
-                           && argv[optind][0] != '!')
+                       if (xs_has_arg(argc, argv))
                                p->policy = argv[optind++];
                        else
                                xtables_error(PARAMETER_PROBLEM,
@@ -1014,15 +1001,8 @@ void do_parse(struct nft_handle *h, int argc, char *argv[],
                                              "You cannot use `-w' from "
                                              "iptables-restore");
                        }
-                       if (optarg) {
-                               if (sscanf(optarg, "%i", &wait) != 1)
-                                       xtables_error(PARAMETER_PROBLEM,
-                                                     "wait seconds not numeric");
-                       } else if (optind < argc && argv[optind][0] != '-'
-                                  && argv[optind][0] != '!')
-                               if (sscanf(argv[optind++], "%i", &wait) != 1)
-                                       xtables_error(PARAMETER_PROBLEM,
-                                                     "wait seconds not numeric");
+
+                       wait = parse_wait_time(argc, argv);
                        break;
 
                case 'W':
@@ -1031,14 +1011,8 @@ void do_parse(struct nft_handle *h, int argc, char *argv[],
                                              "You cannot use `-W' from "
                                              "iptables-restore");
                        }
-                       if (optarg)
-                               parse_wait_interval(optarg, &wait_interval);
-                       else if (optind < argc &&
-                                  argv[optind][0] != '-' &&
-                                  argv[optind][0] != '!')
-                               parse_wait_interval(argv[optind++],
-                                                   &wait_interval);
 
+                       parse_wait_interval(argc, argv, &wait_interval);
                        wait_interval_set = true;
                        break;
 
@@ -1058,9 +1032,7 @@ void do_parse(struct nft_handle *h, int argc, char *argv[],
                        args->bcnt = strchr(args->pcnt + 1, ',');
                        if (args->bcnt)
                            args->bcnt++;
-                       if (!args->bcnt && optind < argc &&
-                           argv[optind][0] != '-' &&
-                           argv[optind][0] != '!')
+                       if (!args->bcnt && xs_has_arg(argc, argv))
                                args->bcnt = argv[optind++];
                        if (!args->bcnt)
                                xtables_error(PARAMETER_PROBLEM,