1 files changed, 132 insertions, 0 deletions
diff --git a/vasprintf.c b/vasprintf.c
new file mode 100644
index 0000000..f87e732
--- /dev/null
+++ b/vasprintf.c
@@ -0,0 +1,132 @@
+#if WANT_VASPRINTF
+/* Derived from libiberty.  */
+/* Like vsprintf but provides a pointer to malloc'd storage, which must
+   be freed by the caller.
+   Copyright (C) 1994, 2003 Free Software Foundation, Inc.
+
+This file is part of the libiberty library.
+Libiberty 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 of the License, or (at your option) any later version.
+
+Libiberty 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 libiberty; see the file COPYING.LIB.  If
+not, write to the Free Software Foundation, Inc., 51 Franklin Street - Fifth Floor,
+Boston, MA 02110-1301, USA.  */
+
+#include <stdarg.h>
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+
+#if !defined (va_copy) && defined (__va_copy)
+#define va_copy(D, S) __va_copy((D), (S))
+#endif
+
+/*
+
+@deftypefn Extension int vasprintf (char **@var{resptr}, const char *@var{format}, va_list @var{args})
+
+Like @code{vsprintf}, but instead of passing a pointer to a buffer,
+you pass a pointer to a pointer.  This function will compute the size
+of the buffer needed, allocate memory with @code{malloc}, and store a
+pointer to the allocated memory in @code{*@var{resptr}}.  The value
+returned is the same as @code{vsprintf} would return.  If memory could
+not be allocated, minus one is returned and @code{NULL} is stored in
+@code{*@var{resptr}}.
+
+@end deftypefn
+
+*/
+
+static int
+int_vasprintf (char **result, const char *format, va_list args)
+{
+  const char *p = format;
+  /* Add one to make sure that it is never zero, which might cause malloc
+     to return NULL.  */
+  int total_width = strlen (format) + 1;
+  va_list ap;
+
+  va_copy (ap, args);
+
+  while (*p != '\0')
+    {
+      if (*p++ == '%')
+	{
+	  while (strchr ("-+ #0", *p))
+	    ++p;
+	  if (*p == '*')
+	    {
+	      ++p;
+	      total_width += abs (va_arg (ap, int));
+	    }
+	  else
+	    total_width += strtoul (p, (char **) &p, 10);
+	  if (*p == '.')
+	    {
+	      ++p;
+	      if (*p == '*')
+		{
+		  ++p;
+		  total_width += abs (va_arg (ap, int));
+		}
+	      else
+	      total_width += strtoul (p, (char **) &p, 10);
+	    }
+	  while (strchr ("hlL", *p))
+	    ++p;
+	  /* Should be big enough for any format specifier except %s and floats.  */
+	  total_width += 30;
+	  switch (*p)
+	    {
+	    case 'd':
+	    case 'i':
+	    case 'o':
+	    case 'u':
+	    case 'x':
+	    case 'X':
+	    case 'c':
+	      (void) va_arg (ap, int);
+	      break;
+	    case 'f':
+	    case 'e':
+	    case 'E':
+	    case 'g':
+	    case 'G':
+	      (void) va_arg (ap, double);
+	      /* Since an ieee double can have an exponent of 307, we'll
+		 make the buffer wide enough to cover the gross case. */
+	      total_width += 307;
+	      break;
+	    case 's':
+	      total_width += strlen (va_arg (ap, char *));
+	      break;
+	    case 'p':
+	    case 'n':
+	      (void) va_arg (ap, char *);
+	      break;
+	    }
+	  p++;
+	}
+    }
+  va_end (ap);
+  *result = (char *) malloc (total_width);
+  if (*result != NULL)
+    return vsprintf (*result, format, args);
+  else
+    return -1;
+}
+
+int
+vasprintf (char **result, const char *format, va_list args)
+{
+  return int_vasprintf (result, format, args);
+}
+#endif