[MINOR] standard: str2mask: string to netmask converter

This function converts a dotted or CIDR value to a netmask.

diff --git a/include/common/standard.h b/include/common/standard.h
index b19f0ccd9f0ae497585bda4311007da48cb98171..fcac72fd598a500346164e70f042f0acd1fc5ba2 100644 (file)
--- a/include/common/standard.h
+++ b/include/common/standard.h
@@ -162,6 +162,12 @@ struct sockaddr_in *str2sa(char *str);
  */
 struct sockaddr_in *str2sa_range(char *str, int *low, int *high);
 
+/* converts <str> to a struct in_addr containing a network mask. It can be
+ * passed in dotted form (255.255.255.0) or in CIDR form (24). It returns 1
+ * if the conversion succeeds otherwise non-zero.
+ */
+int str2mask(const char *str, struct in_addr *mask);
+
 /*
  * converts <str> to two struct in_addr* which must be pre-allocated.
  * The format is "addr[/mask]", where "addr" cannot be empty, and mask

diff --git a/src/standard.c b/src/standard.c
index f841c6dcda09d59725a65d0ebc043928716a2620..e9be0f97f5b4c847af56a8bb40bd9a91cf2a8c4f 100644 (file)
--- a/src/standard.c
+++ b/src/standard.c
@@ -315,6 +315,30 @@ struct sockaddr_in *str2sa_range(char *str, int *low, int *high)
        return &sa;
 }
 
+/* converts <str> to a struct in_addr containing a network mask. It can be
+ * passed in dotted form (255.255.255.0) or in CIDR form (24). It returns 1
+ * if the conversion succeeds otherwise non-zero.
+ */
+int str2mask(const char *str, struct in_addr *mask)
+{
+       if (strchr(str, '.') != NULL) {     /* dotted notation */
+               if (!inet_pton(AF_INET, str, mask))
+                       return 0;
+       }
+       else { /* mask length */
+               char *err;
+               unsigned long len = strtol(str, &err, 10);
+
+               if (!*str || (err && *err) || (unsigned)len > 32)
+                       return 0;
+               if (len)
+                       mask->s_addr = htonl(~0UL << (32 - len));
+               else
+                       mask->s_addr = 0;
+       }
+       return 1;
+}
+
 /*
  * converts <str> to two struct in_addr* which must be pre-allocated.
  * The format is "addr[/mask]", where "addr" cannot be empty, and mask
@@ -326,7 +350,6 @@ int str2net(const char *str, struct in_addr *addr, struct in_addr *mask)
        __label__ out_free, out_err;
        char *c, *s;
        int ret_val;
-       unsigned long len;
 
        s = strdup(str);
        if (!s)
@@ -338,20 +361,8 @@ int str2net(const char *str, struct in_addr *addr, struct in_addr *mask)
        if ((c = strrchr(s, '/')) != NULL) {
                *c++ = '\0';
                /* c points to the mask */
-               if (strchr(c, '.') != NULL) {       /* dotted notation */
-                       if (!inet_pton(AF_INET, c, mask))
-                               goto out_err;
-               }
-               else { /* mask length */
-                       char *err;
-                       len = strtol(c, &err, 10);
-                       if (!*c || (err && *err) || (unsigned)len > 32)
-                               goto out_err;
-                       if (len)
-                               mask->s_addr = htonl(~0UL << (32 - len));
-                       else
-                               mask->s_addr = 0;
-               }
+               if (!str2mask(c, mask))
+                       goto out_err;
        }
        else {
                mask->s_addr = ~0U;