arp, networking/interface.c: eliminate statics

and unneeded on-stack buffers, disable (comment out)
some apparently unused (and buggy) code paths. -700 bytes.

1 files changed, 65 insertions, 67 deletions

diff --git a/networking/arp.c b/networking/arp.c
index 2af6bc970..7a36f44bb 100644
--- a/networking/arp.c
+++ b/networking/arp.c
@@ -27,8 +27,6 @@
 #define DFLT_AF "inet"
 #define DFLT_HW "ether"
 
-#define _PATH_PROCNET_ARP "/proc/net/arp"
-
 #define ARP_OPT_A (0x1)
 #define ARP_OPT_p (0x2)
 #define ARP_OPT_H (0x4)
@@ -64,7 +62,7 @@ static const char *const options[] = {
 /* Called only from main, once */
 static int arp_del(char **args)
 {
-        char host[128];
+        char *host;
         struct arpreq req;
         struct sockaddr sa;
         int flags = 0;
@@ -73,8 +71,8 @@ static int arp_del(char **args)
         memset(&req, 0, sizeof(req));
 
         /* Resolve the host name. */
-        safe_strncpy(host, *args, 128);
-        if (ap->input(0, host, &sa) < 0) {
+        host = *args;
+        if (ap->input(host, &sa) < 0) {
                 bb_herror_msg_and_die("%s", host);
         }
 
@@ -130,8 +128,8 @@ static int arp_del(char **args)
                         if (*++args == NULL)
                                 bb_show_usage();
                         if (strcmp(*args, "255.255.255.255") != 0) {
-                                safe_strncpy(host, *args, 128);
-                                if (ap->input(0, host, &sa) < 0) {
+                                host = *args;
+                                if (ap->input(host, &sa) < 0) {
                                         bb_herror_msg_and_die("%s", host);
                                 }
                                 memcpy(&req.arp_netmask, &sa, sizeof(struct sockaddr));
@@ -213,15 +211,15 @@ static void arp_getdevhw(char *ifname, struct sockaddr *sa,
 /* Called only from main, once */
 static int arp_set(char **args)
 {
-        char host[128];
+        char *host;
         struct arpreq req;
         struct sockaddr sa;
         int flags;
 
         memset(&req, 0, sizeof(req));
 
-        safe_strncpy(host, *args++, 128);
-        if (ap->input(0, host, &sa) < 0) {
+        host = *args++;
+        if (ap->input(host, &sa) < 0) {
                 bb_herror_msg_and_die("%s", host);
         }
         /* If a host has more than one address, use the correct one! */
@@ -285,8 +283,8 @@ static int arp_set(char **args)
                         if (*++args == NULL)
                                 bb_show_usage();
                         if (strcmp(*args, "255.255.255.255") != 0) {
-                                safe_strncpy(host, *args++, 128);
-                                if (ap->input(0, host, &sa) < 0) {
+                                host = *args;
+                                if (ap->input(host, &sa) < 0) {
                                         bb_herror_msg_and_die("%s", host);
                                 }
                                 memcpy(&req.arp_netmask, &sa, sizeof(struct sockaddr));
@@ -362,82 +360,82 @@ arp_disp(const char *name, char *ip, int type, int arp_flags,
 /* Called only from main, once */
 static int arp_show(char *name)
 {
-        char host[100];
+        const char *host;
+        const char *hostname;
+        FILE *fp;
         struct sockaddr sa;
-        char ip[100];
-        char hwa[100];
-        char mask[100];
-        char line[200];
-        char dev[100];
         int type, flags;
-        FILE *fp;
-        const char *hostname;
         int num;
         unsigned entries = 0, shown = 0;
+        char ip[128];
+        char hwa[128];
+        char mask[128];
+        char line[128];
+        char dev[128];
 
-        host[0] = '\0';
-
+        host = NULL;
         if (name != NULL) {
                 /* Resolve the host name. */
-                safe_strncpy(host, name, (sizeof host));
-                if (ap->input(0, host, &sa) < 0) {
-                        bb_herror_msg_and_die("%s", host);
+                if (ap->input(name, &sa) < 0) {
+                        bb_herror_msg_and_die("%s", name);
                 }
-                safe_strncpy(host, ap->sprint(&sa, 1), sizeof(host));
+                host = xstrdup(ap->sprint(&sa, 1));
         }
-        /* Open the PROCps kernel table. */
-        fp = xfopen(_PATH_PROCNET_ARP, "r");
-        /* Bypass header -- read until newline */
-        if (fgets(line, sizeof(line), fp) != (char *) NULL) {
+        fp = xfopen("/proc/net/arp", "r");
+        /* Bypass header -- read one line */
+        fgets(line, sizeof(line), fp);
+
+        /* Read the ARP cache entries. */
+        while (fgets(line, sizeof(line), fp)) {
+
                 mask[0] = '-'; mask[1] = '\0';
                 dev[0] = '-'; dev[1] = '\0';
-                /* Read the ARP cache entries. */
-                for (; fgets(line, sizeof(line), fp);) {
-                        num = sscanf(line, "%s 0x%x 0x%x %100s %100s %100s\n",
-                                                 ip, &type, &flags, hwa, mask, dev);
-                        if (num < 4)
-                                break;
-
-                        entries++;
-                        /* if the user specified hw-type differs, skip it */
-                        if (hw_set && (type != hw->type))
-                                continue;
-
-                        /* if the user specified address differs, skip it */
-                        if (host[0] && strcmp(ip, host) != 0)
-                                continue;
-
-                        /* if the user specified device differs, skip it */
-                        if (device[0] && strcmp(dev, device) != 0)
-                                continue;
-
-                        shown++;
-                        /* This IS ugly but it works -be */
-                        if (option_mask32 & ARP_OPT_n)
-                                hostname = "?";
-                        else {
-                                if (ap->input(0, ip, &sa) < 0)
-                                        hostname = ip;
-                                else
-                                        hostname = ap->sprint(&sa, (option_mask32 & ARP_OPT_n) | 0x8000);
-                                if (strcmp(hostname, ip) == 0)
-                                        hostname = "?";
-                        }
+                /* All these strings can't overflow
+                 * because fgets above reads limited amount of data */
+                num = sscanf(line, "%s 0x%x 0x%x %s %s %s\n",
+                                         ip, &type, &flags, hwa, mask, dev);
+                if (num < 4)
+                        break;
 
-                        arp_disp(hostname, ip, type, flags, hwa, mask, dev);
+                entries++;
+                /* if the user specified hw-type differs, skip it */
+                if (hw_set && (type != hw->type))
+                        continue;
+
+                /* if the user specified address differs, skip it */
+                if (host && strcmp(ip, host) != 0)
+                        continue;
+
+                /* if the user specified device differs, skip it */
+                if (device[0] && strcmp(dev, device) != 0)
+                        continue;
+
+                shown++;
+                /* This IS ugly but it works -be */
+                hostname = "?";
+                if (!(option_mask32 & ARP_OPT_n)) {
+                        if (ap->input(ip, &sa) < 0)
+                                hostname = ip;
+                        else
+                                hostname = ap->sprint(&sa, (option_mask32 & ARP_OPT_n) | 0x8000);
+                        if (strcmp(hostname, ip) == 0)
+                                hostname = "?";
                 }
+
+                arp_disp(hostname, ip, type, flags, hwa, mask, dev);
         }
         if (option_mask32 & ARP_OPT_v)
                 printf("Entries: %d\tSkipped: %d\tFound: %d\n",
                            entries, entries - shown, shown);
 
         if (!shown) {
-                if (hw_set || host[0] || device[0])
+                if (hw_set || host || device[0])
                         printf("No match found in %d entries\n", entries);
         }
-
-        fclose(fp);
-
+        if (ENABLE_FEATURE_CLEAN_UP) {
+                free((char*)host);
+                fclose(fp);
+        }
         return 0;
 }