From 2c692092dfcca0f4c0270b15eb6091dc59d67bc4 Mon Sep 17 00:00:00 2001
From: Ben Kibbey <bjk@luxsci.net>
Date: Fri, 23 Feb 2018 13:19:43 -0800
Subject: [PATCH] Rework str_vasprintf().

---
 src/util-string.c | 42 ++++++++++++++++--------------------------
 1 file changed, 16 insertions(+), 26 deletions(-)

diff --git a/src/util-string.c b/src/util-string.c
index 2cbbdf35..48035691 100644
--- a/src/util-string.c
+++ b/src/util-string.c
@@ -554,39 +554,29 @@ str_asprintf (const char *fmt, ...)
   return len == -1 ? NULL : result;
 }
 
-#define BUFSIZE 128
 int
 str_vasprintf (char **result, const char *fmt, va_list ap)
 {
-  size_t alloc = BUFSIZE;
   char *buf = NULL;
-  int len;
+  int len, len2;
+  va_list cp;
 
-  for (;;)
-    {
-      char *p = pwmd_realloc (buf, alloc * sizeof (char));
-      va_list cp;
+  va_copy (cp, ap);
+  len = vsnprintf (NULL, 0, fmt, cp);
+  va_end (cp);
 
-      if (!p)
-	{
-	  pwmd_free (buf);
-	  return -1;
-	}
-
-      buf = p;
-      va_copy (cp, ap);
-      len = vsnprintf (buf, alloc, fmt, cp);
-      va_end (cp);
+  buf = pwmd_malloc (++len);
+  if (!buf)
+    return -1;
 
-      if (len >= alloc)
-	{
-	  alloc = len + 1;
-	  continue;
-	}
-
-      break;
+  va_copy (cp, ap);
+  len2 = vsnprintf (buf, len, fmt, cp);
+  va_end (cp);
+  if (len-1 != len2)
+    {
+      pwmd_free (buf);
+      return -1;
     }
-
   *result = buf;
-  return len;
+  return len2;
 }
-- 
2.11.4.GIT