Tweak the size computations and reallocations.

diff --git a/ChangeLog b/ChangeLog
index c2d1a2d..9276016 100644 (file)
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+2007-06-10  Bruno Haible  <bruno@clisp.org>
+
+       * lib/vasnprintf.c (VASNPRINTF) [!USE_SNPRINTF]: Remove variable
+       'maxlen'. Ensure only length + width bytes are allocated, not
+       length + 1 + width.
+
 2007-06-09  Bruno Haible  <bruno@clisp.org>
 
        * lib/vasnprintf.c (FCHAR_T, DCHAR_T, TCHAR_T): New macros.

diff --git a/lib/vasnprintf.c b/lib/vasnprintf.c
index d9a1c58..6b7e9c3 100644 (file)
--- a/lib/vasnprintf.c
+++ b/lib/vasnprintf.c
@@ -2812,15 +2812,11 @@ VASNPRINTF (DCHAR_T *resultbuf, size_t *lengthp, const FCHAR_T *format, va_list
 
                for (;;)
                  {
-                   size_t maxlen;
-                   int count;
-                   int retcount;
-
-                   maxlen = allocated - length;
-                   count = -1;
-                   retcount = 0;
+                   int count = -1;
+                   int retcount = 0;
 
 #if USE_SNPRINTF
+                   size_t maxlen = allocated - length;
                    /* SNPRINTF can fail if maxlen > INT_MAX.  */
                    if (maxlen > INT_MAX)
                      goto overflow;
@@ -3035,6 +3031,7 @@ VASNPRINTF (DCHAR_T *resultbuf, size_t *lengthp, const FCHAR_T *format, va_list
                        return NULL;
                      }
 
+#if USE_SNPRINTF
                    /* Make room for the result.  */
                    if (count >= maxlen)
                      {
@@ -3045,12 +3042,24 @@ VASNPRINTF (DCHAR_T *resultbuf, size_t *lengthp, const FCHAR_T *format, va_list
                          xmax (xsum (length, count), xtimes (allocated, 2));
 
                        ENSURE_ALLOCATION (n);
-#if USE_SNPRINTF
                        continue;
-#else
-                       maxlen = allocated - length;
+                     }
 #endif
+
+#if !USE_SNPRINTF
+                   /* Make room for the result.  */
+                   if (count > allocated - length)
+                     {
+                       /* Need at least count bytes.  But allocate
+                          proportionally.  */
+                       size_t n =
+                         xmax (xsum (length, count), xtimes (allocated, 2));
+
+                       ENSURE_ALLOCATION (n);
                      }
+#endif
+
+                   /* Here count <= allocated - length.  */
 
                    /* Perform padding.  */
 #if NEED_PRINTF_FLAG_ZERO
@@ -3058,21 +3067,20 @@ VASNPRINTF (DCHAR_T *resultbuf, size_t *lengthp, const FCHAR_T *format, va_list
                      {
 # if USE_SNPRINTF
                        /* Make room for the result.  */
-                       if (width >= maxlen)
+                       if (width > maxlen)
                          {
                            /* Need at least width bytes.  But allocate
                               proportionally, to avoid looping eternally if
                               snprintf() reports a too small count.  */
                            size_t n =
-                             xmax (xsum (length + 1, width),
+                             xmax (xsum (length, width),
                                    xtimes (allocated, 2));
 
                            length += count;
                            ENSURE_ALLOCATION (n);
                            length -= count;
-                           maxlen = allocated - length; /* > width */
                          }
-                       /* Here width < maxlen.  */
+                       /* Here width <= allocated - length.  */
 # endif
                        {
 # if USE_SNPRINTF
@@ -3131,7 +3139,7 @@ VASNPRINTF (DCHAR_T *resultbuf, size_t *lengthp, const FCHAR_T *format, va_list
                      abort ();
 #endif
 
-                   /* Here still count < maxlen.  */
+                   /* Here still count <= allocated - length.  */
 
 #if USE_SNPRINTF
                    /* The snprintf() result did fit.  */