(argp_parse): Correctly deal with errors from getopt, and allow the user to

  use '?' as a short option.
(KEY_ERR): New macro.
(argp_default_options, argp_default_parser):
  Use -? as the short option for --help.

1 files changed, 40 insertions, 29 deletions

diff --git a/libshouldbeinlibc/argp-parse.c b/libshouldbeinlibc/argp-parse.c
index b9c04b8f..315d6dbc 100644
--- a/libshouldbeinlibc/argp-parse.c
+++ b/libshouldbeinlibc/argp-parse.c
@@ -28,10 +28,10 @@
 
 #include "argp.h"
 
-/* What getopt returns after the end of the options.  */
-#define KEY_END (-1)
-/* What getopt returns for a non-option argument.  */
-#define KEY_ARG 1
+/* Getopt return values.  */
+#define KEY_END (-1)		/* The end of the options.  */
+#define KEY_ARG 1		/* A non-option argument.  */
+#define KEY_ERR '?'		/* An error parsing the options.  */
 
 /* The meta-argument used to prevent any further arguments being interpreted
    as options.  */
@@ -46,12 +46,11 @@
 
 /* ---------------------------------------------------------------- */
 
-#define OPT_HELP	-1
 #define OPT_PROGNAME	-2
 
 static const struct argp_option argp_default_options[] =
 {
-  {"help",	  OPT_HELP,    0, 0,  "Give this help list", -1},
+  {"help",	  '?',    0, 0,  "Give this help list", -1},
   {"program-name",OPT_PROGNAME,"NAME", OPTION_HIDDEN, "Set the program name"},
   {0, 0}
 };
@@ -62,7 +61,7 @@ argp_default_parser (int key, char *arg, struct argp_state *state)
   unsigned usage_flags = ARGP_HELP_STD_HELP;
   switch (key)
     {
-    case OPT_HELP:
+    case '?':
       if (state->flags & ARGP_NO_EXIT)
 	usage_flags &= ~ARGP_HELP_EXIT;
       argp_help (state->argp, stdout, usage_flags);
@@ -419,10 +418,13 @@ argp_parse (const struct argp *argp, int argc, char **argv, unsigned flags,
 	/* Give getopt a chance to parse this.  */
 	{
 	  optind = state.next;	/* Put it back in OPTIND for getopt.  */
+	  optopt = KEY_END;	/* Distinguish KEY_ERR from a real option.  */
 	  opt = getopt_long (state.argc, state.argv, short_opts, long_opts, 0);
 	  state.next = optind;	/* And see what getopt did.  */
+
 	  if (opt == KEY_END)
-	    /* Getopt says there are no more options, so stop using getopt.  */
+	    /* Getopt says there are no more options, so stop using
+	       getopt; we'll continue if necessary on our own.  */
 	    {
 	      try_getopt = 0;
 	      if (state.next > 1
@@ -433,6 +435,14 @@ argp_parse (const struct argp *argp, int argc, char **argv, unsigned flags,
 		   here, whatever happens.  */
 		state.quoted = state.next;
 	    }
+	  else if (opt == KEY_ERR && optopt != KEY_END)
+	    /* KEY_ERR can have the same value as a valid user short
+	       option, but in the case of a real error, getopt sets OPTOPT
+	       to the offending character, which can never be KEY_END.  */
+	    {
+	      err = EINVAL;
+	      break;
+	    }
 	}
       else
 	opt = KEY_END;
@@ -453,29 +463,30 @@ argp_parse (const struct argp *argp, int argc, char **argv, unsigned flags,
 
   mutex_unlock (&getopt_lock);
 
-  if (state.next == state.argc)
-    /* We successfully parsed all arguments!  Call all the parsers again,
-       just a few more times... */
-    {
-      for (group = groups; group < egroup && (!err || err == EINVAL); group++)
-	if (group->args_processed == 0 && group->parser)
-	  err = (*group->parser)(ARGP_KEY_NO_ARGS, 0, &state);
-      for (group = groups; group < egroup && (!err || err == EINVAL); group++)
-	if (group->parser)
-	  err = (*group->parser)(ARGP_KEY_END, 0, &state);
-      if (err == EINVAL)
-	/* EINVAL here just means that ARGP_KEY_END wasn't understood. */
-	err = 0;
-    }
+  if (err == EINVAL && arg_einval)
+    /* Suppress errors generated by unparsed arguments.  */
+    err = 0;
 
-  if (end_index)
-    {
-      if (err == EINVAL && arg_einval)
-	/* As long as there's some way for the user to deal with the
-	   remaining arguments, don't complain.  */
-	err = 0;
+  if (!err)
+    if (state.next == state.argc)
+      /* We successfully parsed all arguments!  Call all the parsers again,
+	 just a few more times... */
+      {
+	for (group = groups; group < egroup && (!err || err ==EINVAL); group++)
+	  if (group->args_processed == 0 && group->parser)
+	    err = (*group->parser)(ARGP_KEY_NO_ARGS, 0, &state);
+	for (group = groups; group < egroup && (!err || err ==EINVAL); group++)
+	  if (group->parser)
+	    err = (*group->parser)(ARGP_KEY_END, 0, &state);
+	if (err == EINVAL)
+	  err = 0;		/* Some parser didn't understand.  */
+      }
+    else if (end_index)
+      /* Return any remaining arguments to the user.  */
       *end_index = state.next;
-    }
+    else
+      /* No way to return the remaining arguments, they must be bogus. */
+      err = EINVAL;
 
   if (err && !(state.flags & ARGP_NO_HELP))
     {