1 files changed, 69 insertions, 6 deletions

diff --git a/str.c b/str.c
index 6521fa6..5b4522f 100644
--- a/str.c
+++ b/str.c
@@ -28,20 +28,43 @@
  * POSSIBILITY OF SUCH DAMAGE.
  */
 
+#include <stdarg.h>
 #include <stdlib.h>
 #include <string.h>
 
 char   *
-str_split(const char *str, char c)
+str_head(const char *str, char c)
+{
+	char   *occ, *result;
+	size_t 	head_len;
+
+	occ = strrchr(str, c);
+	if (!occ || (occ == str && *occ != c))
+		return NULL;
+
+	/* copy head to new buffer */
+	head_len = occ - str + 1;
+	result = malloc(sizeof(char) * head_len);
+	if (result == NULL)
+		return NULL;
+	if (strlcpy(result, str, head_len) < head_len) {
+		free(result);
+		return NULL;
+	}
+	return result;
+}
+
+char   *
+str_tail(const char *str, char c)
 {
 	char   *right, *result;
 	size_t 	right_len;
 
 	right = strrchr(str, c);
-	if (!right || right == str)
+	if (!right || (right == str && *right != c))
 		return NULL;
 
-	/* move right part to new buffer */
+	/* copy right part to new buffer */
 	right_len = strlen(right);
 	result = malloc(sizeof(char) * right_len);
 	if (result == NULL)
@@ -51,9 +74,6 @@ str_split(const char *str, char c)
 		free(result);
 		return NULL;
 	}
-	/* remove right part from src buffer */
-	*right = '\0';
-
 	return result;
 }
 
@@ -70,3 +90,46 @@ str_replace(char *str, char a, char b)
 		tmp++;
 	}
 }
+
+size_t
+str_concat(char **dst,...)
+{
+	va_list str_list;
+	const char *str;
+	char   *concat;
+	size_t 	cur_size, dst_size, w_size;
+
+	/* first compute required size */
+	dst_size = 0;
+	va_start(str_list, dst);
+	while ((str = va_arg(str_list, char *)) != NULL) {
+		dst_size += strlen(str);
+	}
+	va_end(str_list);
+	dst_size++;
+
+	/* alloc result string */
+	*dst = malloc(sizeof(char) * dst_size);
+	if (*dst == NULL)
+		return 0;
+
+	/* concatenate now */
+	concat = *dst;
+	concat[0] = '\0';
+	w_size = 0;
+	va_start(str_list, dst);
+	while ((str = va_arg(str_list, char *)) != NULL) {
+		cur_size = strlen(str);
+		if (strlcpy(concat, str, dst_size) >= dst_size) {
+			w_size = 0;
+			free(dst);
+			break;
+		}
+		w_size += cur_size;
+		concat += cur_size;
+		dst_size -= cur_size;
+	}
+	va_end(str_list);
+
+	return w_size;
+}