Utilize stdbool.h

README.md

@@ -10,8 +10,8 @@ extend [testcases](test/) that help verify safety and correctness.
 ### IPv4
 
 The following example demonstrates the `isinetaddr4` function with
-both valid and invalid inputs. The `isinetaddr4` function returns 1
-when the input given is a valid IPv4 address, and otherwise returns 0.
+both valid and invalid inputs. The `isinetaddr4` function returns `true`
+when the input given is a valid IPv4 address, and otherwise returns `false`.
 
 ```C
 #include <isinetaddr.h>
@@ -121,8 +121,8 @@ foobar is an invalid IPv4 address.
 ### IPv6
 
 The following example demonstrates the `isinetaddr6` function with
-both valid and invalid inputs. The `isinetaddr6` function returns 1
-when the input given is a valid IPv6 address, and otherwise returns 0.
+both valid and invalid inputs. The `isinetaddr6` function returns `true`
+when the input given is a valid IPv6 address, and otherwise returns `false`.
 
 ```C
 #include <isinetaddr.h>

include/isinetaddr.h

@@ -1,4 +1,5 @@
 #pragma once
-int isinetaddr4(const char *str);
-int iscidraddr4(const char *str);
-int isinetaddr6(const char *str);
+#include <stdbool.h>
+bool isinetaddr4(const char *str);
+bool iscidraddr4(const char *str);
+bool isinetaddr6(const char *str);

src/iscidraddr4.c

@@ -2,10 +2,11 @@
 #include <string.h>
 #include <errno.h>
 #include <stdlib.h>
+#include <stdbool.h>
 
-static int in_range(char buf[4], int min, int max);
+static bool in_range(char buf[4], int min, int max);
 
-int
+bool
 iscidraddr4(const char *str)
 {
   size_t offset = 0;
@@ -29,14 +30,14 @@ iscidraddr4(const char *str)
   }
 }
 
-static int
+static bool
 in_range(char buf[4], int min, int max)
 {
   char *err;
   long r;
   errno = 0;
   if (strnlen(buf, 1) == 0) {
-    return 0;
+    return false;
   } else {
     r = strtol(buf, &err, 10);
     return *err == '\0' && errno == 0 && (r >= min && r <= max);

src/isinetaddr4.c

@@ -1,6 +1,7 @@
 #include <ctype.h>
 #include <string.h>
 #include <stdlib.h>
+#include <stdbool.h>
 #include <isinetaddr.h>
 
 static const int  MAX_BUFLEN   = 3;
@@ -8,9 +9,9 @@ static const int  MAX_OCTETS   = 4;
 static const int  MAX_DIGITLEN = 12;
 static const int  MAX_STRLEN   = 16;
 static const char SEP = '.';
-static int within_range(char buf[MAX_BUFLEN]);
+static bool within_range(char buf[MAX_BUFLEN]);
 
-int
+bool
 isinetaddr4(const char *str)
 {
   char buf[MAX_BUFLEN + 1];
@@ -21,31 +22,31 @@ isinetaddr4(const char *str)
   for (size_t i = 0; i < len; i++) {
     if (str[i] == SEP) {
       if (octets == MAX_OCTETS || buflen == 0) {
-        return 0;
+        return false;
       } else {
         buflen = 0;
         bzero(buf, MAX_BUFLEN);
       }
     } else if (isdigit(str[i])) {
       if (buflen == MAX_BUFLEN) {
-        return 0;
+        return false;
       } else {
         buf[buflen++] = str[i];
         digits++;
         if (!within_range(buf)) {
-          return 0;
+          return false;
         } else if (str[i-1] == SEP) {
           octets++;
         }
       }
     } else {
-      return 0;
+      return false;
     }
   }
   return octets == MAX_OCTETS && digits <= MAX_DIGITLEN;
 }
 
-static int
+static bool
 within_range(char buf[MAX_BUFLEN])
 {
   int n = atoi(buf);

src/isinetaddr6.c

@@ -1,6 +1,7 @@
 #include <ctype.h>
 #include <string.h>
 #include <stdlib.h>
+#include <stdbool.h>
 #include <isinetaddr.h>
 
 static const int  MAX_DIGITLEN  = 4;
@@ -9,24 +10,27 @@ static const int  MAX_HEXDIGITS = 32;
 static const int  MAX_STRLEN    = 40;
 static const char SEP = ':';
 
-static int has_consecutive_chars(const char *str, char c, int n);
+static bool has_consecutive_chars(const char *str, char c, int n);
 static char* expand(const char *str, size_t strlen, char *new_str, size_t headlen);
 static size_t get_offset(char *tail);
 
-int
+bool
 isinetaddr6(const char *str)
 {
   int hextets = 1, digitlen = 0, hexdigits = 0;
   size_t len = (str == NULL ? 0 : strnlen(str, MAX_STRLEN));
 
+  if (len == 0) {
+    return false;
+  } else if (strncasecmp(str, "::ffff", 6) == 0) {
+    return isinetaddr4(&str[7]);
+  }
   for (size_t i = 0; i < len; i++) {
     if (has_consecutive_chars(&str[i], SEP, 3)) {
-      return 0;
-    } else if (i == 0 && strncasecmp(str, "::ffff", 6) == 0) {
-      return isinetaddr4(&str[7]);
+      return false;
     } else if (has_consecutive_chars(&str[i], SEP, 2)) {
       if (i == 0 && isinetaddr4(&str[3])) {
-        return 1;
+        return true;
       } else {
         char new_str[MAX_STRLEN];
         return isinetaddr6(expand(str, len, new_str, i));
@@ -37,18 +41,18 @@ isinetaddr6(const char *str)
       digitlen++;
       hexdigits++;
       if (digitlen > MAX_DIGITLEN) {
-        return 0;
+        return false;
       } else if (str[i-1] == SEP) {
         hextets++;
       }
     } else {
-      return 0;
+      return false;
     }
   }
   return hextets == MAX_HEXTETS && hexdigits <= MAX_HEXDIGITS;
 }
 
-static int
+static bool
 has_consecutive_chars(const char *str, char c, int n)
 {
   for (int i = 0; i < n; i++) {