libiberty/asprintf.c

   1 /* Like sprintf but provides a pointer to malloc'd storage, which must
   2    be freed by the caller.
   3    Copyright (C) 1997, 2003 Free Software Foundation, Inc.
   4    Contributed by Cygnus Solutions.
   5
   6 This file is part of the libiberty library.
   7 Libiberty is free software; you can redistribute it and/or
   8 modify it under the terms of the GNU Library General Public
   9 License as published by the Free Software Foundation; either
  10 version 2 of the License, or (at your option) any later version.
  11
  12 Libiberty is distributed in the hope that it will be useful,
  13 but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15 Library General Public License for more details.
  16
  17 You should have received a copy of the GNU Library General Public
  18 License along with libiberty; see the file COPYING.LIB.  If
  19 not, write to the Free Software Foundation, Inc., 51 Franklin Street - Fifth Floor,
  20 Boston, MA 02110-1301, USA.  */
  21
  22 #ifdef HAVE_CONFIG_H
  23 #include "config.h"
  24 #endif
  25 #include "ansidecl.h"
  26 #include "libiberty.h"
  27
  28 #include <stdarg.h>
  29
  30 /*
  31
  32 @deftypefn Extension int asprintf (char **@var{resptr}, const char *@var{format}, ...)
  33
  34 Like @code{sprintf}, but instead of passing a pointer to a buffer, you
  35 pass a pointer to a pointer.  This function will compute the size of
  36 the buffer needed, allocate memory with @code{malloc}, and store a
  37 pointer to the allocated memory in @code{*@var{resptr}}.  The value
  38 returned is the same as @code{sprintf} would return.  If memory could
  39 not be allocated, minus one is returned and @code{NULL} is stored in
  40 @code{*@var{resptr}}.
  41
  42 @end deftypefn
  43
  44 */
  45
  46 int
  47 asprintf (char **buf, const char *fmt, ...)
  48 {
  49   int status;
  50   VA_OPEN (ap, fmt);
  51   VA_FIXEDARG (ap, char **, buf);
  52   VA_FIXEDARG (ap, const char *, fmt);
  53   status = vasprintf (buf, fmt, ap);
  54   VA_CLOSE (ap);
  55   return status;
  56 }