Added silc_getopt.

[silc.git] / lib / silcutil / silcgetopt.c

diff --git a/lib/silcutil/silcgetopt.c b/lib/silcutil/silcgetopt.c
new file mode 100644 (file)
index 0000000..5697617
--- /dev/null
+++ b/lib/silcutil/silcgetopt.c
@@ -0,0 +1,85 @@
+/*
+
+  silcgetopt.c
+
+  Author: Pekka Riikonen <priikone@silcnet.org>
+
+  Copyright (C) 2007 Pekka Riikonen
+
+  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; version 2 of the License.
+
+  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.
+
+*/
+
+#include "silc.h"
+
+/* Getopt, like getopt(3). */
+
+int silc_getopt(int argc, char **argv, const char *optstring, SilcGetOpt op)
+{
+  register int c;
+  register char *cp;
+  SilcBool optional = FALSE, optional_found = FALSE;
+
+  SILC_VERIFY(op);
+
+  op->opt_arg = NULL;
+
+  if (op->opt_sp == 1) {
+    if (op->opt_index >= argc ||
+       argv[op->opt_index][0] != '-' || argv[op->opt_index][1] == '\0') {
+      return -1;
+    } else if (strcmp(argv[op->opt_index], "--") == 0) {
+      op->opt_index++;
+      return -1;
+    }
+  }
+  op->opt_option = c = argv[op->opt_index][op->opt_sp];
+
+  if (c == ':' || (cp = strchr(optstring, c)) == NULL) {
+    if (op->opt_error)
+      fprintf(stderr, "%s: illegal option -- %c\n", argv[0], c);
+    if (argv[op->opt_index][++op->opt_sp] == '\0') {
+      op->opt_index++;
+      op->opt_sp = 1;
+    }
+    return '?';
+  }
+
+  if (*++cp == ':') {
+    /* Check for optional argument (::), must be written -oarg, not -o arg. */
+    if (strlen(cp) && *(cp + 1) == ':') {
+      optional = TRUE;
+      if (argv[op->opt_index][op->opt_sp + 1] != '\0')
+       optional_found = TRUE;
+    }
+
+    if (argv[op->opt_index][op->opt_sp + 1] != '\0')
+      op->opt_arg = &argv[op->opt_index++][op->opt_sp + 1];
+    else if (++op->opt_index >= argc) {
+      if (!optional && !optional_found) {
+       if (op->opt_error)
+         fprintf(stderr, "%s: option requires an argument -- %c\n",
+                 argv[0], c);
+       op->opt_sp = 1;
+       return ':';
+      }
+    } else if (!optional || optional_found)
+      op->opt_arg = argv[op->opt_index++];
+    op->opt_sp = 1;
+  } else {
+    if (argv[op->opt_index][++op->opt_sp] == '\0') {
+      op->opt_sp = 1;
+      op->opt_index++;
+    }
+    op->opt_arg = NULL;
+  }
+
+  return c;
+}