1 files changed, 122 insertions, 0 deletions
diff --git a/libc/misc/getopt.c b/libc/misc/getopt.c
new file mode 100644
index 0000000..d951214
--- /dev/null
+++ b/libc/misc/getopt.c
@@ -0,0 +1,122 @@
+
+/*
+ * From: gwyn@brl-tgr.ARPA (Doug Gwyn <gwyn>) Newsgroups: net.sources
+ * Subject: getopt library routine Date: 30 Mar 85 04:45:33 GMT
+ */
+/*
+ * getopt -- public domain version of standard System V routine
+ * 
+ * Strictly enforces the System V Command Syntax Standard; provided by D A
+ * Gwyn of BRL for generic ANSI C implementations
+ * 
+ * #define STRICT to prevent acceptance of clustered options with arguments
+ * and ommision of whitespace between option and arg.
+ */
+
+#include <stdio.h>
+#include <string.h>
+
+int   opterr = 1;		/* error => print message */
+int   optind = 1;		/* next argv[] index */
+char *optarg = NULL;		/* option parameter if any */
+
+static int
+Err(name, mess, c)		/* returns '?' */
+char *name;			/* program name argv[0] */
+char *mess;			/* specific message */
+int   c;			/* defective option letter */
+{
+   if (opterr)
+   {
+      (void) fprintf(stderr,
+		     "%s: %s -- %c\n",
+		     name, mess, c
+	  );
+   }
+
+   return '?';			/* erroneous-option marker */
+}
+
+int
+getopt(argc, argv, optstring)	/* returns letter, '?', EOF */
+int   argc;			/* argument count from main */
+char *argv[];			/* argument vector from main */
+char *optstring;		/* allowed args, e.g. "ab:c" */
+{
+   static int sp = 1;		/* position within argument */
+   register int osp;		/* saved `sp' for param test */
+#ifndef STRICT
+   register int oind;		/* saved `optind' for param test */
+#endif
+   register int c;		/* option letter */
+   register char *cp;		/* -> option in `optstring' */
+
+   optarg = NULL;
+
+   if (sp == 1)			/* fresh argument */
+      if (optind >= argc	/* no more arguments */
+	  || argv[optind][0] != '-'	/* no more options */
+	  || argv[optind][1] == '\0'	/* not option; stdin */
+	  )
+	 return EOF;
+      else if (strcmp(argv[optind], "--") == 0)
+      {
+	 ++optind;		/* skip over "--" */
+	 return EOF;		/* "--" marks end of options */
+      }
+
+   c = argv[optind][sp];	/* option letter */
+   osp = sp++;			/* get ready for next letter */
+
+#ifndef STRICT
+   oind = optind;		/* save optind for param test */
+#endif
+   if (argv[optind][sp] == '\0')/* end of argument */
+   {
+      ++optind;			/* get ready for next try */
+      sp = 1;			/* beginning of next argument */
+   }
+
+   if (c == ':' || c == '?'	/* optstring syntax conflict */
+       || (cp = strchr(optstring, c)) == NULL	/* not found */
+       )
+      return Err(argv[0], "illegal option", c);
+
+   if (cp[1] == ':')		/* option takes parameter */
+   {
+#ifdef STRICT
+      if (osp != 1)
+	 return Err(argv[0],
+		    "option must not be clustered",
+		    c
+	     );
+
+      if (sp != 1)		/* reset by end of argument */
+	 return Err(argv[0],
+		    "option must be followed by white space",
+		    c
+	     );
+
+#else
+      if (oind == optind)	/* argument w/o whitespace */
+      {
+	 optarg = &argv[optind][sp];
+	 sp = 1;		/* beginning of next argument */
+      }
+
+      else
+#endif
+      if (optind >= argc)
+	 return Err(argv[0],
+		    "option requires an argument",
+		    c
+	     );
+
+      else			/* argument w/ whitespace */
+	 optarg = argv[optind];
+
+      ++optind;			/* skip over parameter */
+   }
+
+   return c;
+}