Add getopt. Not using yet.

bin/getopt.c

@@ -0,0 +1,231 @@
+/*
+Copyright (c) 2012, Kim Gräsman
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are met:
+    * Redistributions of source code must retain the above copyright
+      notice, this list of conditions and the following disclaimer.
+    * Redistributions in binary form must reproduce the above copyright
+      notice, this list of conditions and the following disclaimer in the
+      documentation and/or other materials provided with the distribution.
+    * Neither the name of Kim Gräsman nor the
+      names of contributors may be used to endorse or promote products
+      derived from this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL KIM GRÄSMAN BE LIABLE FOR ANY
+DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*/
+
+#include "lub/getopt.h"
+
+#include <stddef.h>
+#include <string.h>
+
+const int no_argument = 0;
+const int required_argument = 1;
+const int optional_argument = 2;
+
+char* optarg;
+int optopt;
+/* The variable optind [...] shall be initialized to 1 by the system. */
+int optind = 1;
+int opterr;
+
+static char* optcursor = NULL;
+
+/* Implemented based on [1] and [2] for optional arguments.
+   optopt is handled FreeBSD-style, per [3].
+   Other GNU and FreeBSD extensions are purely accidental. 
+   
+[1] http://pubs.opengroup.org/onlinepubs/000095399/functions/getopt.html
+[2] http://www.kernel.org/doc/man-pages/online/pages/man3/getopt.3.html
+[3] http://www.freebsd.org/cgi/man.cgi?query=getopt&sektion=3&manpath=FreeBSD+9.0-RELEASE
+*/
+int getopt(int argc, char* const argv[], const char* optstring) {
+  int optchar = -1;
+  const char* optdecl = NULL;
+
+  optarg = NULL;
+  opterr = 0;
+  optopt = 0;
+
+  /* Unspecified, but we need it to avoid overrunning the argv bounds. */
+  if (optind >= argc)
+    goto no_more_optchars;
+
+  /* If, when getopt() is called argv[optind] is a null pointer, getopt() 
+     shall return -1 without changing optind. */
+  if (argv[optind] == NULL)
+    goto no_more_optchars;
+
+  /* If, when getopt() is called *argv[optind]  is not the character '-', 
+     getopt() shall return -1 without changing optind. */
+  if (*argv[optind] != '-')
+    goto no_more_optchars;
+
+  /* If, when getopt() is called argv[optind] points to the string "-", 
+     getopt() shall return -1 without changing optind. */
+  if (strcmp(argv[optind], "-") == 0)
+    goto no_more_optchars;
+
+  /* If, when getopt() is called argv[optind] points to the string "--", 
+     getopt() shall return -1 after incrementing optind. */
+  if (strcmp(argv[optind], "--") == 0) {
+    ++optind;
+    goto no_more_optchars;
+  }
+
+  if (optcursor == NULL || *optcursor == '\0')
+    optcursor = argv[optind] + 1;
+
+  optchar = *optcursor;
+
+  /* FreeBSD: The variable optopt saves the last known option character 
+     returned by getopt(). */
+  optopt = optchar;
+
+  /* The getopt() function shall return the next option character (if one is 
+     found) from argv that matches a character in optstring, if there is 
+     one that matches. */
+  optdecl = strchr(optstring, optchar);
+  if (optdecl) {
+    /* [I]f a character is followed by a colon, the option takes an
+       argument. */
+    if (optdecl[1] == ':') {
+      optarg = ++optcursor;
+      if (*optarg == '\0') {
+        /* GNU extension: Two colons mean an option takes an
+           optional arg; if there is text in the current argv-element 
+           (i.e., in the same word as the option name itself, for example, 
+           "-oarg"), then it is returned in optarg, otherwise optarg is set
+           to zero. */
+        if (optdecl[2] != ':') {
+          /* If the option was the last character in the string pointed to by
+             an element of argv, then optarg shall contain the next element
+             of argv, and optind shall be incremented by 2. If the resulting
+             value of optind is greater than argc, this indicates a missing 
+             option-argument, and getopt() shall return an error indication.
+
+             Otherwise, optarg shall point to the string following the
+             option character in that element of argv, and optind shall be
+             incremented by 1.
+          */
+          if (++optind < argc) {
+            optarg = argv[optind];
+          } else {
+            /* If it detects a missing option-argument, it shall return the 
+               colon character ( ':' ) if the first character of optstring
+               was a colon, or a question-mark character ( '?' ) otherwise.
+            */
+            optarg = NULL;
+            optchar = (optstring[0] == ':') ? ':' : '?';
+          }
+        } else {
+          optarg = NULL;
+        }
+      }
+
+      optcursor = NULL;
+    }
+  } else {
+    /* If getopt() encounters an option character that is not contained in 
+       optstring, it shall return the question-mark ( '?' ) character. */
+    optchar = '?';
+  }
+
+  if (optcursor == NULL || *++optcursor == '\0')
+    ++optind;
+
+  return optchar;
+
+no_more_optchars:
+  optcursor = NULL;
+  return -1;
+}
+
+/* Implementation based on [1].
+
+[1] http://www.kernel.org/doc/man-pages/online/pages/man3/getopt.3.html
+*/
+int getopt_long(int argc, char* const argv[], const char* optstring, 
+  const struct option* longopts, int* longindex) {
+  const struct option* o = longopts;
+  const struct option* match = NULL;
+  int num_matches = 0;
+  size_t argument_name_length = 0;
+  const char* current_argument = NULL;
+  int retval = -1;
+
+  optarg = NULL;
+  optopt = 0;
+
+  if (optind >= argc)
+    return -1;
+
+  if (strlen(argv[optind]) < 3 || strncmp(argv[optind], "--", 2) != 0)
+    return getopt(argc, argv, optstring);
+
+  /* It's an option; starts with -- and is longer than two chars. */
+  current_argument = argv[optind] + 2;
+  argument_name_length = strcspn(current_argument, "=");
+  for (; o->name; ++o) {
+    if (strncmp(o->name, current_argument, argument_name_length) == 0) {
+      match = o;
+      ++num_matches;
+    }
+  }
+
+  if (num_matches == 1) {
+    /* If longindex is not NULL, it points to a variable which is set to the
+       index of the long option relative to longopts. */
+    if (longindex)
+      *longindex = (match - longopts);
+
+    /* If flag is NULL, then getopt_long() shall return val. 
+       Otherwise, getopt_long() returns 0, and flag shall point to a variable
+       which shall be set to val if the option is found, but left unchanged if
+       the option is not found. */
+    if (match->flag)
+      *(match->flag) = match->val;
+
+    retval = match->flag ? 0 : match->val;
+
+    if (match->has_arg != no_argument) {
+      optarg = strchr(argv[optind], '=');
+      if (optarg != NULL)
+        ++optarg;
+
+      if (match->has_arg == required_argument) {
+        /* Only scan the next argv for required arguments. Behavior is not
+           specified, but has been observed with Ubuntu and Mac OSX. */
+        if (optarg == NULL && ++optind < argc) {
+          optarg = argv[optind];
+        }
+
+        if (optarg == NULL)
+          retval = ':';
+      }
+    } else if (strchr(argv[optind], '=')) {
+      /* An argument was provided to a non-argument option. 
+         I haven't seen this specified explicitly, but both GNU and BSD-based
+         implementations show this behavior.
+      */
+      retval = '?';
+    }
+  } else {
+    /* Unknown option or ambiguous match. */
+    retval = '?';
+  }
+
+  ++optind;
+  return retval;
+}

bin/getopt.h

@@ -0,0 +1,31 @@
+#ifndef INCLUDED_GETOPT_PORT_H
+#define INCLUDED_GETOPT_PORT_H
+
+#if defined(__cplusplus)
+extern "C" {
+#endif
+
+extern const int no_argument;
+extern const int required_argument;
+extern const int optional_argument;
+
+extern char* optarg;
+extern int optind, opterr, optopt;
+
+struct option {
+  const char* name;
+  int has_arg;
+  int* flag;
+  int val;
+};
+
+int getopt(int argc, char* const argv[], const char* optstring);
+
+int getopt_long(int argc, char* const argv[],
+  const char* optstring, const struct option* longopts, int* longindex);
+
+#if defined(__cplusplus)
+}
+#endif
+
+#endif /* INCLUDED_GETOPT_PORT_H */