Formatted output functions for Unicode strings.

[gnulib.git] / lib / unistdio / u-vsnprintf.h

diff --git a/lib/unistdio/u-vsnprintf.h b/lib/unistdio/u-vsnprintf.h
new file mode 100644 (file)
index 0000000..d7c6215
--- /dev/null
+++ b/lib/unistdio/u-vsnprintf.h
@@ -0,0 +1,59 @@
+/* Formatted output to strings.
+   Copyright (C) 1999, 2002, 2006-2007 Free Software Foundation, Inc.
+
+   This program is free software; you can redistribute it and/or modify it
+   under the terms of the GNU Library General Public License as published
+   by the Free Software Foundation; either version 2, or (at your option)
+   any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Library General Public License for more details.
+
+   You should have received a copy of the GNU Library General Public
+   License along with this program; if not, write to the Free Software
+   Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
+   USA.  */
+
+/* Some systems, like OSF/1 4.0 and Woe32, don't have EOVERFLOW.  */
+#ifndef EOVERFLOW
+# define EOVERFLOW E2BIG
+#endif
+
+int
+VSNPRINTF (DCHAR_T *buf, size_t size, const FCHAR_T *format, va_list args)
+{
+  size_t length;
+  DCHAR_T *result;
+
+  if (size == 0)
+    buf = NULL;
+  else
+    length = size;
+  result = VASNPRINTF (buf, &length, format, args);
+  if (result == NULL)
+    return -1;
+
+  if (result != buf)
+    {
+      if (size != 0)
+       {
+         /* The result did not fit into the buffer.  Copy the initial segment
+            into the buffer, truncating it if necessary.  */
+         size_t n = (length < size ? length : size - 1);
+         DCHAR_CPY (buf, result, n);
+         buf[n] = '\0';
+       }
+      free (result);
+    }
+
+  if (length > INT_MAX)
+    {
+      errno = EOVERFLOW;
+      return -1;
+    }
+
+  /* Return the number of resulting units, excluding the trailing NUL.  */
+  return length;
+}