X-Git-Url: http://git.tuebingen.mpg.de/?p=paraslash.git;a=blobdiff_plain;f=string.c;h=752fb8f945d1a381b7b7af4e65ed56b646df8d47;hp=eb8b12ece58ecd03e1507932751d1961de0084be;hb=31bc1f853b69884dd8659efe7455386211648476;hpb=4f0d81d30685a98ec5b1058c09be8833e7fd147f

diff --git a/string.c b/string.c
index eb8b12ec..752fb8f9 100644
--- a/string.c
+++ b/string.c
@@ -91,7 +91,7 @@ __must_check __malloc void *para_calloc(size_t size)
 }
 
 /**
- * Pparaslash's version of strdup().
+ * Paraslash's version of strdup().
  *
  * \param s The string to be duplicated.
  *
@@ -484,7 +484,15 @@ int for_each_line_ro(char *buf, size_t size, line_handler_t *line_handler,
  *
  * This function prints into the buffer given by \a b at the offset which is
  * also given by \a b. If there is not enough space to hold the result, the
- * buffer size is doubled until the underlying call to vsnprintf() succeeds.
+ * buffer size is doubled until the underlying call to vsnprintf() succeeds
+ * or the size of the buffer exceeds the maximal size specified in \a pb.
+ *
+ * In the latter case the unmodified \a buf and \a offset values as well as the
+ * private_data pointer of \a b are passed to the \a max_size_handler of \a b.
+ * If this function succeeds, i.e. returns a non-negative value, the offset of
+ * \a b is reset to zero and the given data is written to the beginning of the
+ * buffer.
+ *
  * Upon return, the offset of \a b is adjusted accordingly so that subsequent
  * calls to this function append data to what is already contained in the
  * buffer.
@@ -505,26 +513,35 @@ __printf_2_3 int para_printf(struct para_buffer *b, const char *fmt, ...)
 		b->buf = para_malloc(128);
 		b->size = 128;
 		b->offset = 0;
-	} else if (b->size <= b->offset + 1) {
-		b->size *= 2;
-		b->buf = para_realloc(b->buf, b->size);
 	}
 	while (1) {
 		char *p = b->buf + b->offset;
 		size_t size = b->size - b->offset;
 		va_list ap;
-		va_start(ap, fmt);
-		ret = vsnprintf(p, size, fmt, ap);
-		va_end(ap);
-		if (ret > -1 && ret < size) { /* success */
-			b->offset += ret;
-			break;
+		if (size) {
+			va_start(ap, fmt);
+			ret = vsnprintf(p, size, fmt, ap);
+			va_end(ap);
+			if (ret > -1 && ret < size) { /* success */
+				b->offset += ret;
+				return ret;
+			}
+		}
+		/* check if we may grow the buffer */
+		if (!b->max_size || 2 * b->size < b->max_size) { /* yes */
+			/* try again with more space */
+			b->size *= 2;
+			b->buf = para_realloc(b->buf, b->size);
+			continue;
 		}
-		/* try again with more space */
-		b->size *= 2;
-		b->buf = para_realloc(b->buf, b->size);
+		/* can't grow buffer */
+		if (!b->offset || !b->max_size_handler) /* message too large */
+			return -ERRNO_TO_PARA_ERROR(ENOSPC);
+		ret = b->max_size_handler(b->buf, b->offset, b->private_data);
+		if (ret < 0)
+			return ret;
+		b->offset = 0;
 	}
-	return ret;
 }
 
 /** \cond LLONG_MAX and LLONG_LIN might not be defined. */