string: split and fix strdup and strndup (DONE)

CMakeLists.txt

@@ -146,6 +146,7 @@ set(SOURCES
   src/libc/string/strncat.c
   src/libc/string/strncmp.c
   src/libc/string/strncpy.c
+  src/libc/string/strndup.c
   src/libc/string/strnlen.c
   src/libc/string/strrchr.c)
 

STATUS

@@ -136,8 +136,8 @@ DONE:       Function/symbol/macro is defined, builds, links, and is tested
      - strchrnul: DONE
 !    - strcasecmp: TODO
 !    - strncasecmp: TODO
-!    - strdup: TODO
-!    - strndup: TODO
+     - strdup: DONE
+     - strndup: DONE
 
 7.22 <tgmath.h> => GCC
 

src/libc/string/strdup.c

@@ -1,64 +1,10 @@
 #include <string.h>
 #include <stdlib.h>
 
-/*
-** The  strdup()  function  returns a pointer to a new string which is a
-** duplicate of the string s. Memory for the new string is obtained with
-** malloc(), and can be freed with free().
-*/
-char *strdup(const char *s)
+char *strdup(char const *s)
 {
-	size_t len;
-	void *dump;
-
-	// Check error
-	if (s == NULL)
-		return (NULL);
-
-	// Check len
-	len = strlen(s);
-	if (len == 0)
-		return (NULL);
-
-	// try to allocate the new area
-	dump = malloc(len);
-	if (dump == NULL)
-		return (NULL);
-
-	// dump the area and return
-	memcpy(dump, s, len);
-	return (dump);
+	size_t len = strlen(s) + 1;
+	char *copy = malloc(len);
+	if(copy) memcpy(copy, s, len);
+	return copy;
 }
-
-/*
-** The strndup() function is similar, but copies at most n bytes. If s is longer
-** than n, only n bytes are copied, and a terminating null byte ('\0') is added.
-*/
-char *strndump(const char *s, size_t n)
-{
-	size_t len;
-	char *dump;
-
-	// Check error
-	if (s == NULL)
-		return (NULL);
-
-	// Check len
-	len = strnlen(s, n);
-	if (len == 0)
-		return (NULL);
-
-	// try to allocate the new area
-	dump = malloc(len);
-	if (dump == NULL)
-		return (NULL);
-
-	// dump the area, set the null byte and return
-	memcpy(dump, s, len);
-	dump[len - 1] = '\0';
-	return (dump);
-
-}
-
-//TODO: strdupa()
-//TODO: strndupa()

src/libc/string/strndup.c

@@ -0,0 +1,15 @@
+#include <string.h>
+#include <stdlib.h>
+
+char *strndup(const char *s, size_t n)
+{
+	size_t len = strnlen(s, n) + 1;
+	char *copy = malloc(len);
+
+	if(copy) {
+		memcpy(copy, s, len);
+		copy[len - 1] = 0;
+	}
+
+	return copy;
+}