ifupdown: code shrink

function                                             old     new   delta
next_word                                             78      63     -15
ifupdown_main                                       2381    2170    -211
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 0/2 up/down: 0/-226)           Total: -226 bytes

1 files changed, 51 insertions, 95 deletions

diff --git a/networking/ifupdown.c b/networking/ifupdown.c
index 68ea01a67..a794bf76a 100644
--- a/networking/ifupdown.c
+++ b/networking/ifupdown.c
@@ -584,32 +584,24 @@ static const struct address_family_t addr_inet = {
 
 static char *next_word(char **buf)
 {
-        unsigned short length;
+        unsigned length;
         char *word;
 
-        if (!buf || !*buf || !**buf) {
-                return NULL;
-        }
-
         /* Skip over leading whitespace */
         word = skip_whitespace(*buf);
 
-        /* Skip over comments */
-        if (*word == '#') {
+        /* Stop on EOL/comments */
+        if (*word == '#' || *word == '\0')
                 return NULL;
-        }
 
-        /* Find the length of this word */
+        /* Find the length of this word (can't be 0) */
         length = strcspn(word, " \t\n");
-        if (length == 0) {
-                return NULL;
-        }
+
+        /* Unless we are already at NUL, store NUL and advance */
+        if (word[length] != '\0')
+                word[length++] = '\0';
+
         *buf = word + length;
-        /*DBU:[dave@cray.com] if we are already at EOL dont't increment beyond it */
-        if (**buf) {
-                **buf = '\0';
-                (*buf)++;
-        }
 
         return word;
 }
@@ -686,27 +678,26 @@ static struct interfaces_file_t *read_interfaces(const char *filename)
 
                 if (strcmp(firstword, "mapping") == 0) {
 #if ENABLE_FEATURE_IFUPDOWN_MAPPING
-                        currmap = xzalloc(sizeof(struct mapping_defn_t));
+                        currmap = xzalloc(sizeof(*currmap));
 
                         while ((firstword = next_word(&buf_ptr)) != NULL) {
-                                if (currmap->max_matches == currmap->n_matches) {
+                                if (currmap->n_matches >= currmap->max_matches) {
                                         currmap->max_matches = currmap->max_matches * 2 + 1;
-                                        currmap->match = xrealloc(currmap->match, sizeof(currmap->match) * currmap->max_matches);
+                                        currmap->match = xrealloc(currmap->match, sizeof(*currmap->match) * currmap->max_matches);
                                 }
-
                                 currmap->match[currmap->n_matches++] = xstrdup(firstword);
                         }
-                        currmap->max_mappings = 0;
-                        currmap->n_mappings = 0;
-                        currmap->mapping = NULL;
-                        currmap->script = NULL;
+                        /*currmap->max_mappings = 0; - done by xzalloc */
+                        /*currmap->n_mappings = 0;*/
+                        /*currmap->mapping = NULL;*/
+                        /*currmap->script = NULL;*/
                         {
                                 struct mapping_defn_t **where = &defn->mappings;
                                 while (*where != NULL) {
                                         where = &(*where)->next;
                                 }
                                 *where = currmap;
-                                currmap->next = NULL;
+                                /*currmap->next = NULL;*/
                         }
                         debug_noise("Added mapping\n");
 #endif
@@ -727,44 +718,36 @@ static struct interfaces_file_t *read_interfaces(const char *filename)
                         char *method_name;
                         llist_t *iface_list;
 
-                        currif = xzalloc(sizeof(struct interface_defn_t));
+                        currif = xzalloc(sizeof(*currif));
                         iface_name = next_word(&buf_ptr);
                         address_family_name = next_word(&buf_ptr);
                         method_name = next_word(&buf_ptr);
 
-                        if (buf_ptr == NULL) {
-                                bb_error_msg("too few parameters for line \"%s\"", buf);
-                                return NULL;
-                        }
+                        if (method_name == NULL)
+                                bb_error_msg_and_die("too few parameters for line \"%s\"", buf);
 
                         /* ship any trailing whitespace */
                         buf_ptr = skip_whitespace(buf_ptr);
 
-                        if (buf_ptr[0] != '\0') {
-                                bb_error_msg("too many parameters \"%s\"", buf);
-                                return NULL;
-                        }
+                        if (buf_ptr[0] != '\0' /* && buf_ptr[0] != '#' */)
+                                bb_error_msg_and_die("too many parameters \"%s\"", buf);
 
                         currif->iface = xstrdup(iface_name);
 
                         currif->address_family = get_address_family(addr_fams, address_family_name);
-                        if (!currif->address_family) {
-                                bb_error_msg("unknown address type \"%s\"", address_family_name);
-                                return NULL;
-                        }
+                        if (!currif->address_family)
+                                bb_error_msg_and_die("unknown address type \"%s\"", address_family_name);
 
                         currif->method = get_method(currif->address_family, method_name);
-                        if (!currif->method) {
-                                bb_error_msg("unknown method \"%s\"", method_name);
-                                return NULL;
-                        }
+                        if (!currif->method)
+                                bb_error_msg_and_die("unknown method \"%s\"", method_name);
 
                         for (iface_list = defn->ifaces; iface_list; iface_list = iface_list->link) {
                                 struct interface_defn_t *tmp = (struct interface_defn_t *) iface_list->data;
-                                if ((strcmp(tmp->iface, currif->iface) == 0) &&
-                                        (tmp->address_family == currif->address_family)) {
-                                        bb_error_msg("duplicate interface \"%s\"", tmp->iface);
-                                        return NULL;
+                                if ((strcmp(tmp->iface, currif->iface) == 0)
+                                 && (tmp->address_family == currif->address_family)
+                                ) {
+                                        bb_error_msg_and_die("duplicate interface \"%s\"", tmp->iface);
                                 }
                         }
                         llist_add_to_end(&(defn->ifaces), (char*)currif);
@@ -787,73 +770,50 @@ static struct interfaces_file_t *read_interfaces(const char *filename)
                 } else {
                         switch (currently_processing) {
                         case IFACE:
-                                {
+                                if (buf_ptr[0] == '\0')
+                                        bb_error_msg_and_die("option with empty value \"%s\"", buf);
+
+                                if (strcmp(firstword, "up") != 0
+                                 && strcmp(firstword, "down") != 0
+                                 && strcmp(firstword, "pre-up") != 0
+                                 && strcmp(firstword, "post-down") != 0
+                                ) {
                                         int i;
-
-                                        if (strlen(buf_ptr) == 0) {
-                                                bb_error_msg("option with empty value \"%s\"", buf);
-                                                return NULL;
-                                        }
-
-                                        if (strcmp(firstword, "up") != 0
-                                                        && strcmp(firstword, "down") != 0
-                                                        && strcmp(firstword, "pre-up") != 0
-                                                        && strcmp(firstword, "post-down") != 0) {
-                                                for (i = 0; i < currif->n_options; i++) {
-                                                        if (strcmp(currif->option[i].name, firstword) == 0) {
-                                                                bb_error_msg("duplicate option \"%s\"", buf);
-                                                                return NULL;
-                                                        }
-                                                }
+                                        for (i = 0; i < currif->n_options; i++) {
+                                                if (strcmp(currif->option[i].name, firstword) == 0)
+                                                        bb_error_msg_and_die("duplicate option \"%s\"", buf);
                                         }
                                 }
                                 if (currif->n_options >= currif->max_options) {
-                                        struct variable_t *opt;
-
-                                        currif->max_options = currif->max_options + 10;
-                                        opt = xrealloc(currif->option, sizeof(*opt) * currif->max_options);
-                                        currif->option = opt;
+                                        currif->max_options += 10;
+                                        currif->option = xrealloc(currif->option, sizeof(*currif->option) * currif->max_options);
                                 }
+                                debug_noise("\t%s=%s\n", firstword, buf_ptr);
                                 currif->option[currif->n_options].name = xstrdup(firstword);
                                 currif->option[currif->n_options].value = xstrdup(buf_ptr);
-                                if (!currif->option[currif->n_options].name) {
-                                        perror(filename);
-                                        return NULL;
-                                }
-                                if (!currif->option[currif->n_options].value) {
-                                        perror(filename);
-                                        return NULL;
-                                }
-                                debug_noise("\t%s=%s\n", currif->option[currif->n_options].name,
-                                                currif->option[currif->n_options].value);
                                 currif->n_options++;
                                 break;
                         case MAPPING:
 #if ENABLE_FEATURE_IFUPDOWN_MAPPING
                                 if (strcmp(firstword, "script") == 0) {
-                                        if (currmap->script != NULL) {
-                                                bb_error_msg("duplicate script in mapping \"%s\"", buf);
-                                                return NULL;
-                                        } else {
-                                                currmap->script = xstrdup(next_word(&buf_ptr));
-                                        }
+                                        if (currmap->script != NULL)
+                                                bb_error_msg_and_die("duplicate script in mapping \"%s\"", buf);
+                                        currmap->script = xstrdup(next_word(&buf_ptr));
                                 } else if (strcmp(firstword, "map") == 0) {
-                                        if (currmap->max_mappings == currmap->n_mappings) {
+                                        if (currmap->n_mappings >= currmap->max_mappings) {
                                                 currmap->max_mappings = currmap->max_mappings * 2 + 1;
                                                 currmap->mapping = xrealloc(currmap->mapping, sizeof(char *) * currmap->max_mappings);
                                         }
                                         currmap->mapping[currmap->n_mappings] = xstrdup(next_word(&buf_ptr));
                                         currmap->n_mappings++;
                                 } else {
-                                        bb_error_msg("misplaced option \"%s\"", buf);
-                                        return NULL;
+                                        bb_error_msg_and_die("misplaced option \"%s\"", buf);
                                 }
 #endif
                                 break;
                         case NONE:
                         default:
-                                bb_error_msg("misplaced option \"%s\"", buf);
-                                return NULL;
+                                bb_error_msg_and_die("misplaced option \"%s\"", buf);
                         }
                 }
                 free(buf);
@@ -1138,7 +1098,7 @@ static llist_t *read_iface_state(void)
 int ifupdown_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
 int ifupdown_main(int argc, char **argv)
 {
-        int (*cmds)(struct interface_defn_t *) = NULL;
+        int (*cmds)(struct interface_defn_t *);
         struct interfaces_file_t *defn;
         llist_t *target_list = NULL;
         const char *interfaces = "/etc/network/interfaces";
@@ -1161,10 +1121,6 @@ int ifupdown_main(int argc, char **argv)
         defn = read_interfaces(interfaces);
         debug_noise("\ndone reading %s\n\n", interfaces);
 
-        if (!defn) {
-                return EXIT_FAILURE;
-        }
-
         startup_PATH = getenv("PATH");
         if (!startup_PATH) startup_PATH = "";