1 files changed, 74 insertions, 0 deletions
diff --git a/klibc/klibc/getopt.c b/klibc/klibc/getopt.c
new file mode 100644
index 0000000000..5a992dcdd7
--- /dev/null
+++ b/klibc/klibc/getopt.c
@@ -0,0 +1,74 @@
+/*
+ * getopt.c
+ *
+ * Simple POSIX getopt(), no GNU extensions...
+ */
+
+#include <stdint.h>
+#include <unistd.h>
+#include <string.h>
+
+char *optarg;
+int optind = 1;
+int opterr, optopt;
+static const char *__optptr;
+
+int getopt(int argc, char * const *argv, const char *optstring)
+{
+  const char *carg = argv[optind];
+  const char *osptr;
+  int opt;
+
+  /* We don't actually need argc */
+  (void)argc;
+
+  /* First, eliminate all non-option cases */
+  
+  if ( !carg || carg[0] != '-' || !carg[1] ) {
+    return -1;
+  }
+
+  if ( carg[1] == '-' && !carg[2] ) {
+    optind++;
+    return -1;
+  }
+
+  if ( (uintptr_t)(__optptr-carg) > (uintptr_t)strlen(carg) )
+    __optptr = carg+1;	/* Someone frobbed optind, change to new opt. */
+
+  opt = *__optptr++;
+
+  if ( opt != ':' && (osptr = strchr(optstring, opt)) ) {
+    if ( osptr[1] == ':' ) {
+      if ( *__optptr ) {
+	/* Argument-taking option with attached argument */
+	optarg = (char *)__optptr;
+	optind++;
+      } else {
+	/* Argument-taking option with non-attached argument */
+	if ( argv[optind+1] ) {
+	  optarg = (char *)argv[optind+1];
+	  optind += 2;
+	} else {
+	  /* Missing argument */
+	  return (optstring[0] == ':') ? ':' : '?';
+	}
+      }
+      return opt;
+    } else {
+      /* Non-argument-taking option */
+      /* __optptr will remember the exact position to resume at */
+      if ( ! *__optptr )
+	optind++;
+      return opt;
+    }
+  } else {
+    /* Unknown option */
+    optopt = opt;
+    if ( ! *__optptr )
+      optind++;
+    return '?';
+  }
+}
+
+