Use an easier looping method, and use more const.

diff --git a/dhcp.c b/dhcp.c
index f7ef3a6f585d3b77b0f7483888fc0c89a2971957..b52041c69152119d5903647da26b20027dad68ae 100644 (file)
--- a/dhcp.c
+++ b/dhcp.c
@@ -57,13 +57,13 @@
  * practically never. See RFC3396 for details. */
 static uint8_t *dhcp_opt_buffer = NULL;
 
-struct dhcp_option {
+struct dhcp_opt {
        uint8_t option;
        int type;
        const char *var;
 };
 
-const struct dhcp_option dhcp_opts[] = {
+static const struct dhcp_opt const dhcp_opts[] = {
        { 1,    IPV4 | REQUEST, "subnet_mask" },
        { 2,    UINT32,         "time_offset" },
        { 3,    IPV4 | ARRAY | REQUEST, "routers" },
@@ -158,40 +158,36 @@ const struct dhcp_option dhcp_opts[] = {
 void
 print_options(void)
 {
-       unsigned int i;
+       const struct dhcp_opt *opt;
 
-       for (i = 0; i < sizeof(dhcp_opts) / sizeof(dhcp_opts[0]); i++)
-               if (dhcp_opts[i].var)
-                       printf("%03d %s\n",
-                              dhcp_opts[i].option,
-                              dhcp_opts[i].var);
+       for (opt = dhcp_opts; opt->option; opt++)
+               if (opt->var)
+                       printf("%03d %s\n", opt->option, opt->var);
 }
 
 int make_reqmask(struct options *options, char **opts, int add)
 {
        char *token;
        char *p = *opts;
-       uint8_t i;
-       const char *v;
-       int max = sizeof(dhcp_opts) / sizeof(dhcp_opts[0]);
+       const struct dhcp_opt *opt;
 
        while ((token = strsep(&p, ", "))) {
                if (*token == '\0')
                        continue;
-               for (i = 0; i < max; i++) {
-                       if (!(v = dhcp_opts[i].var))
+               for (opt = dhcp_opts; opt->option; opt++) {
+                       if (!opt->var)
                                continue;
-                       if (strcmp(v, token) == 0) {
+                       if (strcmp(opt->var, token) == 0) {
                                if (add == 1)
                                        add_reqmask(options->reqmask,
-                                                   dhcp_opts[i].option);
+                                                   opt->option);
                                else
                                        del_reqmask(options->reqmask,
-                                                   dhcp_opts[i].option);
+                                                   opt->option);
                                break;
                        }
                }
-               if (i >= max) {
+               if (!opt->option) {
                        *opts = token;
                        errno = ENOENT;
                        return -1;
@@ -203,33 +199,30 @@ int make_reqmask(struct options *options, char **opts, int add)
 static int
 valid_length(uint8_t option, int dl, int *type)
 {
-       uint8_t i;
+       const struct dhcp_opt *opt;
        ssize_t sz;
-       int t;
 
        if (dl == 0)
                return -1;
 
-       for (i = 0; i < sizeof(dhcp_opts) / sizeof(dhcp_opts[0]); i++) {
-               if (dhcp_opts[i].option != option)
+       for (opt = dhcp_opts; opt->option; opt++) {
+               if (opt->option != option)
                        continue;
 
-               t = dhcp_opts[i].type;
                if (type)
-                       *type = t;
+                       *type = opt->type;
 
-               if (t == 0 || t & STRING || t & RFC3442)
+               if (opt->type == 0 || opt->type & STRING || opt->type & RFC3442)
                        return 0;
 
                sz = 0;
-               if (t & UINT32 || t & IPV4)
+               if (opt->type & UINT32 || opt->type & IPV4)
                        sz = sizeof(uint32_t);
-               if (t & UINT16)
+               if (opt->type & UINT16)
                        sz = sizeof(uint16_t);
-               if (t & UINT8)
+               if (opt->type & UINT8)
                        sz = sizeof(uint8_t);
-
-               if (t & IPV4 || t & ARRAY)
+               if (opt->type & IPV4 || opt->type & ARRAY)
                        return dl % sz;
                return (dl == sz ? 0 : -1);
        }
@@ -721,7 +714,7 @@ make_message(struct dhcp_message **message,
        time_t up = uptime() - iface->start_uptime;
        uint32_t ul;
        uint16_t sz;
-       uint8_t o;
+       const struct dhcp_opt *opt;
 
        dhcp = xzalloc(sizeof (*dhcp));
        m = (uint8_t *)dhcp;
@@ -876,19 +869,18 @@ make_message(struct dhcp_message **message,
                *p++ = DHCP_PARAMETERREQUESTLIST;
                n_params = p;
                *p++ = 0;
-               for (l = 0; l < sizeof(dhcp_opts) / sizeof(dhcp_opts[0]); l++) {
-                       o = dhcp_opts[l].option;
-                       if (!(dhcp_opts[l].type & REQUEST || 
-                             has_reqmask(options->reqmask, o)))
+               for (opt = dhcp_opts; opt->option; opt++) {
+                       if (!(opt->type & REQUEST || 
+                             has_reqmask(options->reqmask, opt->option)))
                                continue;
-                       switch (o) {
+                       switch (opt->option) {
                        case DHCP_RENEWALTIME:  /* FALLTHROUGH */
                        case DHCP_REBINDTIME:
                                if (type == DHCP_INFORM)
                                        continue;
                                break;
                        }
-                       *p++ = o;
+                       *p++ = opt->option;
                }
                *n_params = p - n_params - 1;
        }
@@ -1130,7 +1122,7 @@ configure_env(char **env, const char *prefix, const struct dhcp_message *dhcp)
        struct in_addr net;
        struct in_addr brd;
        char *val, *v;
-       const struct dhcp_option *opt;
+       const struct dhcp_opt *opt;
        ssize_t len, e = 0;
        char **ep;
        char cidr[4];
@@ -1139,8 +1131,7 @@ configure_env(char **env, const char *prefix, const struct dhcp_message *dhcp)
        get_option_uint8(&overl, dhcp, DHCP_OPTIONSOVERLOADED);
 
        if (!env) {
-               for (i = 0; i < sizeof(dhcp_opts) / sizeof(dhcp_opts[0]); i++) {
-                       opt = &dhcp_opts[i];
+               for (opt = dhcp_opts; opt->option; opt++) {
                        if (!opt->var)
                                continue;
                        if (get_option(dhcp, opt->option))
@@ -1181,8 +1172,7 @@ configure_env(char **env, const char *prefix, const struct dhcp_message *dhcp)
        if (*dhcp->servername && !(overl & 2))
                _setenv(&ep, prefix, "server_name", (char *)dhcp->servername);
 
-       for (i = 0; i < sizeof(dhcp_opts) / sizeof(dhcp_opts[0]); i++) {
-               opt = &dhcp_opts[i];
+       for (opt = dhcp_opts; opt->option; opt++) {
                if (!opt->var)
                        continue;
                val = NULL;