--- a/buffer.c	Wed Oct 05 19:46:31 2011 +0200
+++ b/buffer.c	Fri Oct 07 16:10:33 2011 +0200
@@ -26,11 +26,13 @@
 static int	buffer_grow(struct buffer *, size_t);
 
 /*
- * Initialize a new buffer with the optional `str' as begin of buffer.
+ * Create a new buffer with initial size `length'. If type is set to BUFFER_AUTO
+ * the buffer will grow automatically increasing the size by `length' bytes. On
+ * BUFFER_FIXED type the buffer won't grow.
  */
 
 struct buffer *
-buffer_new(const char *str, size_t bsize, int flags)
+buffer_new(enum buffer_type type, int length)
 {
 	struct buffer *buf;
 
@@ -38,20 +40,15 @@
 		return NULL;
 
 	memset(buf, 0, sizeof (struct buffer));
-	buf->bsize	= (bsize == 0) ? BUFFER_DEFAULT_BSIZE : bsize;
+	buf->bsize	= (length == 0) ? BUFFER_DEFAULT_BSIZE : length;
 	buf->size	= buf->bsize + 1;
-	buf->flags	= flags;
+	buf->type	= type;
 
 	if ((buf->data = calloc(buf->size, 1)) == NULL) {
 		free(buf);
 		return NULL;
 	}
 
-	if (str != NULL && buffer_strcat(buf, str) < 0) {
-		free(buf);
-		return NULL;
-	}
-
 	return buf;
 }
 
@@ -68,7 +65,7 @@
 	if (buffer_grow(buf, length) < 0)
 		return -1;
 
-	if (!(buf->flags & BUFFER_AUTO))
+	if (buf->type == BUFFER_AUTO)
 		length = buf->size - buf->length - 1;
 
 	strncpy(buf->data + buf->length, str, length);
@@ -78,7 +75,7 @@
 }
 
 /*
- * Append the character c to the end of buffer.
+ * Append the character `c' to the end of buffer.
  */
 
 int
@@ -87,7 +84,7 @@
 	if (buffer_grow(buf, 1) < 0)
 		return -1;
 
-	if (!(buf->flags & BUFFER_AUTO) && buf->size - buf->length - 1 <= 2)
+	if (buf->type != BUFFER_AUTO && buf->size - buf->length - 1 <= 2)
 		return -1;
 
 	buf->data[buf->length++]	= c;
@@ -107,7 +104,7 @@
 		return -1;
 
 	/* Do not truncate void pointer */
-	if (!(buf->flags & BUFFER_AUTO) && size > (buf->size - buf->length - 1))
+	if (buf->type == BUFFER_AUTO && size > (buf->size - buf->length - 1))
 		return -1;
 
 	memcpy(buf->data + buf->length, data, size);
@@ -130,7 +127,7 @@
 	 * vsnprintf on windows returns -1 instead of the number of bytes that
 	 * should be printed...
 	 */
-	if (buf->flags & BUFFER_AUTO) {
+	if (buf->type == BUFFER_AUTO) {
 		do {
 			va_copy(ap_save, ap);
 			nb = vsnprintf(buf->data + buf->length,
@@ -238,7 +235,7 @@
 	if ((buf->size - buf->length) > needed)
 		return 0;
 
-	if (buf->flags & BUFFER_AUTO) {
+	if (buf->type == BUFFER_AUTO) {
 		newlen = buf->size;
 		while (newlen - buf->length - 1 <= needed)
 			newlen += buf->bsize;

--- a/buffer.h	Wed Oct 05 19:46:31 2011 +0200
+++ b/buffer.h	Fri Oct 07 16:10:33 2011 +0200
@@ -21,34 +21,30 @@
 
 #define	BUFFER_DEFAULT_BSIZE	512
 
-#define BUFFER_FIXED	0x00
-#define BUFFER_AUTO	0x01
-
 #include <stdarg.h>
 
-struct buffer {
-	char	*data;		/* string buffer */
-	size_t	length;		/* string's length */
-
-	int	flags;		/* buffer's flags (default AUTO) */
-
-	/* Private should not be modified by user */
-	size_t	size;		/* current size */
-	size_t	bsize;		/* block size */
+enum buffer_type {
+	BUFFER_FIXED	= 0,
+	BUFFER_AUTO	= 1
 };
 
-struct buffer	*buffer_new(const char *, size_t, int);
-#define buffer_new_auto(size)	buffer_new(NULL, size, BUFFER_AUTO)
-#define buffer_new_fixed(max)	buffer_new(NULL, max, BUFFER_FIXED)
+struct buffer {
+	enum buffer_type type;		/* buffer type (default AUTO) */
+	char		*data;		/* string buffer */
+	size_t		length;		/* string's real length */
+	size_t		size;		/* current allocated size */
+	int		bsize;		/* initial length */
+};
 
-int	buffer_strcat(struct buffer *, const char *);
-int	buffer_putc(struct buffer *buf, char);
-int	buffer_bcat(struct buffer *, const void *, size_t);
-int	buffer_vprintf(struct buffer *, const char *, va_list);
-int	buffer_printf(struct buffer *, const char *, ...);
-int	buffer_shrink(struct buffer *);
-char	*buffer_end(struct buffer *);
-void	buffer_clear(struct buffer *);
-void	buffer_free(struct buffer *);
+struct buffer	*buffer_new(enum buffer_type, int);
+int		buffer_strcat(struct buffer *, const char *);
+int		buffer_putc(struct buffer *buf, char);
+int		buffer_bcat(struct buffer *, const void *, size_t);
+int		buffer_vprintf(struct buffer *, const char *, va_list);
+int		buffer_printf(struct buffer *, const char *, ...);
+int		buffer_shrink(struct buffer *);
+char		*buffer_end(struct buffer *);
+void		buffer_clear(struct buffer *);
+void		buffer_free(struct buffer *);
 
 #endif /* _BUFFER_H_ */