add printf-like primitive to the buffers.

Signed-off-by: Pierre Habouzit <madcoder@debian.org>

diff --git a/lib-lib/buffer.c b/lib-lib/buffer.c
index b442721..71f31b4 100644 (file)
--- a/lib-lib/buffer.c
+++ b/lib-lib/buffer.c
@@ -107,3 +107,33 @@ void mutt_buffer_add(BUFFER *buf, const char *s, ssize_t len)
     *buf->dptr = '\0';
 }
 
+ssize_t buffer_addvf(buffer_t *buf, const char *fmt, va_list args)
+{
+    ssize_t len;
+    va_list ap;
+
+    va_copy(ap, args);
+    buffer_ensure(buf, BUFSIZ);
+
+    len = vsnprintf(buf->data + buf->len, buf->size - buf->len, fmt, args);
+    if (len < 0) {
+        len = 0;
+    }
+    if (len >= buf->size - buf->len) {
+        buffer_ensure(buf, len);
+        vsnprintf(buf->data + buf->len, buf->size - buf->len, fmt, ap);
+    }
+    buf->len += len;
+    buf->data[buf->len] = '\0';
+
+    return len;
+}
+
+ssize_t buffer_addf(buffer_t *buf, const char *fmt, ...) {
+    ssize_t res;
+    va_list args;
+    va_start(args, fmt);
+    res = buffer_addvf(buf, fmt, args);
+    va_end(args);
+    return res;
+}

diff --git a/lib-lib/buffer.h b/lib-lib/buffer.h
index dd9d936..6d62f2a 100644 (file)
--- a/lib-lib/buffer.h
+++ b/lib-lib/buffer.h
@@ -93,6 +93,12 @@ static inline void buffer_reset(buffer_t *buf) {
     }
 }
 
+ssize_t buffer_addvf(buffer_t *buf, const char *fmt, va_list)
+    __attribute__((format(printf, 2, 0)));
+
+ssize_t buffer_addf(buffer_t *buf, const char *fmt, ...)
+    __attribute__((format(printf, 2, 3)));
+
 
 /****** LEGACY BUFFERS *******/