--- /dev/null
+/* Parse arguments from a string and prepend them to an argv.
+ Copyright 1999, 2000 Free Software Foundation, Inc.
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU 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 General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software
+ Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
+ 02111-1307, USA. */
+
+/* Written by Paul Eggert <eggert@twinsun.com>. */
+
+#ifdef HAVE_CONFIG_H
+# include <config.h>
+#endif
+#include "prepargs.h"
+#include <sys/types.h>
+#include <xalloc.h>
+
+#include <ctype.h>
+
+/* IN_CTYPE_DOMAIN (C) is nonzero if the unsigned char C can safely be given
+ as an argument to <ctype.h> macros like "isspace". */
+#ifdef STDC_HEADERS
+# define IN_CTYPE_DOMAIN(c) 1
+#else
+# define IN_CTYPE_DOMAIN(c) ((c) <= 0177)
+#endif
+
+#define ISSPACE(c) (IN_CTYPE_DOMAIN (c) && isspace (c))
+
+/* Find the white-space-separated options specified by OPTIONS, and
+ using BUF to store copies of these options, set ARGV[0], ARGV[1],
+ etc. to the option copies. Return the number N of options found.
+ Do not set ARGV[N] to NULL. If ARGV is NULL, do not store ARGV[0]
+ etc. Backslash can be used to escape whitespace (and backslashes). */
+static int
+prepend_args (char const *options, char *buf, char **argv)
+{
+ char const *o = options;
+ char *b = buf;
+ int n = 0;
+
+ for (;;)
+ {
+ while (ISSPACE ((unsigned char) *o))
+ o++;
+ if (!*o)
+ return n;
+ if (argv)
+ argv[n] = b;
+ n++;
+
+ do
+ if ((*b++ = *o++) == '\\' && *o)
+ b[-1] = *o++;
+ while (*o && ! ISSPACE ((unsigned char) *o));
+
+ *b++ = '\0';
+ }
+}
+
+/* Prepend the whitespace-separated options in OPTIONS to the argument
+ vector of a main program with argument count *PARGC and argument
+ vector *PARGV. */
+void
+prepend_default_options (char const *options, int *pargc, char ***pargv)
+{
+ if (options)
+ {
+ char *buf = xmalloc (strlen (options) + 1);
+ int prepended = prepend_args (options, buf, (char **) NULL);
+ int argc = *pargc;
+ char * const *argv = *pargv;
+ char **pp = (char **) xmalloc ((prepended + argc + 1) * sizeof *pp);
+ *pargc = prepended + argc;
+ *pargv = pp;
+ *pp++ = *argv++;
+ pp += prepend_args (options, buf, pp);
+ while ((*pp++ = *argv++))
+ continue;
+ }
+}