X-Git-Url: https://review.openocd.org/gitweb?p=openocd.git;a=blobdiff_plain;f=src%2Fhelper%2Flog.c;h=694e8a8b2126aa98b181f8bcd8e3c5d1051ebf47;hp=b38987232eb290b06533bf03d367c0eb07a7e6ed;hb=d74d72c73a692fbdf222c4cb595a5d015f4611c9;hpb=f955b90d28874dc238a03178503a804b3c38582a

diff --git a/src/helper/log.c b/src/helper/log.c
index b38987232e..694e8a8b21 100644
--- a/src/helper/log.c
+++ b/src/helper/log.c
@@ -269,29 +269,34 @@ char *alloc_printf(const char *fmt, va_list ap)
 	/* no buffer at the beginning, force realloc to do the job */
 	char *string = NULL;
 	
-	/* start with minimal length to exercise all the code paths */
-	int size = 1;
+	/* start with buffer size suitable for typical messages */
+	int size = 128;
 
 	for (;;)
 	{
-		size *= 2; /* double the buffer size */
+		char *t = string;
+		string = realloc(string, size);
+		if (string == NULL)
+		{
+			if (t != NULL)
+				free(t);
+			return NULL;
+		}
+
+		va_list ap_copy;
+		va_copy(ap_copy, ap);
 
-			char *t = string;
-			string = realloc(string, size);
-			if (string == NULL)
-			{
-				if (t != NULL)
-					free(t);
-				return NULL;
-			}
-	
 		int ret;
-		ret = vsnprintf(string, size, fmt, ap);
+		ret = vsnprintf(string, size, fmt, ap_copy);
+		
+		va_end(ap_copy);
+		
 		/* NB! The result of the vsnprintf() might be an *EMPTY* string! */
 		if ((ret >= 0) && ((ret + 1) < size))
 			break;
 
 		/* there was just enough or not enough space, allocate more in the next round */
+		size *= 2; /* double the buffer size */
 	}
 	
 	/* the returned buffer is by principle guaranteed to be at least one character longer */