text: /* vi: set sw=4 ts=4: */
  /*
   * getopt.c - Enhanced implementation of BSD getopt(1)
   *   Copyright (c) 1997, 1998, 1999, 2000  Frodo Looijaard <frodol@dds.nl>
   *
   * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
   */
  
  /*
   * Version 1.0-b4: Tue Sep 23 1997. First public release.
   * Version 1.0: Wed Nov 19 1997.
   *   Bumped up the version number to 1.0
   *   Fixed minor typo (CSH instead of TCSH)
   * Version 1.0.1: Tue Jun 3 1998
   *   Fixed sizeof instead of strlen bug
   *   Bumped up the version number to 1.0.1
   * Version 1.0.2: Thu Jun 11 1998 (not present)
   *   Fixed gcc-2.8.1 warnings
   *   Fixed --version/-V option (not present)
   * Version 1.0.5: Tue Jun 22 1999
   *   Make -u option work (not present)
   * Version 1.0.6: Tue Jun 27 2000
   *   No important changes
   * Version 1.1.0: Tue Jun 30 2000
   *   Added NLS support (partly written by Arkadiusz Mi<B6>kiewicz
   *     <misiek@misiek.eu.org>)
   * Ported to Busybox - Alfred M. Szmidt <ams@trillian.itslinux.org>
   *  Removed --version/-V and --help/-h in
   *  Removed parse_error(), using bb_error_msg() from Busybox instead
   *  Replaced our_malloc with xmalloc and our_realloc with xrealloc
   *
   */
  
  #include <getopt.h>
  #include "libbb.h"
  
  /* NON_OPT is the code that is returned when a non-option is found in '+'
     mode */
  enum {
  	NON_OPT = 1,
  #if ENABLE_GETOPT_LONG
  /* LONG_OPT is the code that is returned when a long option is found. */
  	LONG_OPT = 2
  #endif
  };
  
  /* For finding activated option flags. Must match getopt32 call! */
  enum {
  	OPT_o	= 0x1,	// -o
  	OPT_n	= 0x2,	// -n
  	OPT_q	= 0x4,	// -q
  	OPT_Q	= 0x8,	// -Q
  	OPT_s	= 0x10,	// -s
  	OPT_T	= 0x20,	// -T
  	OPT_u	= 0x40,	// -u
  #if ENABLE_GETOPT_LONG
  	OPT_a	= 0x80,	// -a
  	OPT_l	= 0x100, // -l
  #endif
  	SHELL_IS_TCSH = 0x8000, /* hijack this bit for other purposes */
  };
  
  /* 0 is getopt_long, 1 is getopt_long_only */
  #define alternative  (option_mask32 & OPT_a)
  
  #define quiet_errors (option_mask32 & OPT_q)
  #define quiet_output (option_mask32 & OPT_Q)
  #define quote        (!(option_mask32 & OPT_u))
  #define shell_TCSH   (option_mask32 & SHELL_IS_TCSH)
  
  /*
   * This function 'normalizes' a single argument: it puts single quotes around
   * it and escapes other special characters. If quote is false, it just
   * returns its argument.
   * Bash only needs special treatment for single quotes; tcsh also recognizes
   * exclamation marks within single quotes, and nukes whitespace.
   * This function returns a pointer to a buffer that is overwritten by
   * each call.
   */
  static const char *normalize(const char *arg)
  {
  	char *bufptr;
  #if ENABLE_FEATURE_CLEAN_UP
  	static char *BUFFER = NULL;
  	free(BUFFER);
  #else
  	char *BUFFER;
  #endif
  
  	if (!quote) { /* Just copy arg */
  		BUFFER = xstrdup(arg);
  		return BUFFER;
  	}
  
  	/* Each character in arg may take up to four characters in the result:
  	   For a quote we need a closing quote, a backslash, a quote and an
  	   opening quote! We need also the global opening and closing quote,
  	   and one extra character for '\0'. */
  	BUFFER = xmalloc(strlen(arg)*4 + 3);
  
  	bufptr = BUFFER;
  	*bufptr ++= '\'';
  
  	while (*arg) {
  		if (*arg == '\'') {
  			/* Quote: replace it with: '\'' */
  			*bufptr ++= '\'';
  			*bufptr ++= '\\';
  			*bufptr ++= '\'';
  			*bufptr ++= '\'';
  		} else if (shell_TCSH && *arg == '!') {
  			/* Exclamation mark: replace it with: \! */
  			*bufptr ++= '\'';
  			*bufptr ++= '\\';
  			*bufptr ++= '!';
  			*bufptr ++= '\'';
  		} else if (shell_TCSH && *arg == '\n') {
  			/* Newline: replace it with: \n */
  			*bufptr ++= '\\';
  			*bufptr ++= 'n';
  		} else if (shell_TCSH && isspace(*arg)) {
  			/* Non-newline whitespace: replace it with \<ws> */
  			*bufptr ++= '\'';
  			*bufptr ++= '\\';
  			*bufptr ++= *arg;
  			*bufptr ++= '\'';
  		} else
  			/* Just copy */
  			*bufptr ++= *arg;
  		arg++;
  	}
  	*bufptr ++= '\'';
  	*bufptr ++= '\0';
  	return BUFFER;
  }
  
  /*
   * Generate the output. argv[0] is the program name (used for reporting errors).
   * argv[1..] contains the options to be parsed. argc must be the number of
   * elements in argv (ie. 1 if there are no options, only the program name),
   * optstr must contain the short options, and longopts the long options.
   * Other settings are found in global variables.
   */
  #if !ENABLE_GETOPT_LONG
  #define generate_output(argv,argc,optstr,longopts) generate_output(argv,argc,optstr)
  #endif
  static int generate_output(char **argv, int argc, const char *optstr, const struct option *longopts)
  {
  	int exit_code = 0; /* We assume everything will be OK */
  	unsigned opt;
  #if ENABLE_GETOPT_LONG
  	int longindex;
  #endif
  	const char *charptr;
  
  	if (quiet_errors) /* No error reporting from getopt(3) */
  		opterr = 0;
  	optind = 0; /* Reset getopt(3) */
  
  	while (1) {
  		opt =
  #if ENABLE_GETOPT_LONG
  			alternative ?
  			getopt_long_only(argc, argv, optstr, longopts, &longindex) :
  			getopt_long(argc, argv, optstr, longopts, &longindex);
  #else
  			getopt(argc, argv, optstr);
  #endif
  		if (opt == EOF)
  			break;
  		if (opt == '?' || opt == ':' )
  			exit_code = 1;
  		else if (!quiet_output) {
  #if ENABLE_GETOPT_LONG
  			if (opt == LONG_OPT) {
  				printf(" --%s", longopts[longindex].name);
  				if (longopts[longindex].has_arg)
  					printf(" %s",
  						normalize(optarg ? optarg : ""));
  			} else
  #endif
  			if (opt == NON_OPT)
  				printf(" %s", normalize(optarg));
  			else {
  				printf(" -%c", opt);
  				charptr = strchr(optstr,opt);
  				if (charptr != NULL && *++charptr == ':')
  					printf(" %s",
  						normalize(optarg ? optarg : ""));
  			}
  		}
  	}
  
  	if (!quiet_output) {
  		printf(" --");
  		while (optind < argc)
  			printf(" %s", normalize(argv[optind++]));
  		bb_putchar('\n');
  	}
  	return exit_code;
  }
  
  #if ENABLE_GETOPT_LONG
  /*
   * Register several long options. options is a string of long options,
   * separated by commas or whitespace.
   * This nukes options!
   */
  static struct option *add_long_options(struct option *long_options, char *options)
  {
  	int long_nr = 0;
  	int arg_opt, tlen;
  	char *tokptr = strtok(options, ", \t\n");
  
  	if (long_options)
  		while (long_options[long_nr].name)
  			long_nr++;
  
  	while (tokptr) {
  		arg_opt = no_argument;
  		tlen = strlen(tokptr);
  		if (tlen) {
  			tlen--;
  			if (tokptr[tlen] == ':') {
  				arg_opt = required_argument;
  				if (tlen && tokptr[tlen-1] == ':') {
  					tlen--;
  					arg_opt = optional_argument;
  				}
  				tokptr[tlen] = '\0';
  				if (tlen == 0)
  					bb_error_msg_and_die("empty long option specified");
  			}
  			long_options = xrealloc(long_options,
  					sizeof(long_options[0]) * (long_nr+2));
  			long_options[long_nr].has_arg = arg_opt;
  			long_options[long_nr].flag = NULL;
  			long_options[long_nr].val = LONG_OPT;
  			long_options[long_nr].name = xstrdup(tokptr);
  			long_nr++;
  			memset(&long_options[long_nr], 0, sizeof(long_options[0]));
  		}
  		tokptr = strtok(NULL, ", \t\n");
  	}
  	return long_options;
  }
  #endif
  
  static void set_shell(const char *new_shell)
  {
  	if (!strcmp(new_shell,"bash") || !strcmp(new_shell,"sh"))
  		return;
  	if (!strcmp(new_shell,"tcsh") || !strcmp(new_shell,"csh"))
  		option_mask32 |= SHELL_IS_TCSH;
  	else
  		bb_error_msg("unknown shell '%s', assuming bash", new_shell);
  }
  
  
  /* Exit codes:
   *   0) No errors, successful operation.
   *   1) getopt(3) returned an error.
   *   2) A problem with parameter parsing for getopt(1).
   *   3) Internal error, out of memory
   *   4) Returned for -T
   */
  
  #if ENABLE_GETOPT_LONG
  static const char getopt_longopts[] ALIGN1 =
  	"options\0"      Required_argument "o"
  	"longoptions\0"  Required_argument "l"
  	"quiet\0"        No_argument       "q"
  	"quiet-output\0" No_argument       "Q"
  	"shell\0"        Required_argument "s"
  	"test\0"         No_argument       "T"
  	"unquoted\0"     No_argument       "u"
  	"alternative\0"  No_argument       "a"
  	"name\0"         Required_argument "n"
  	;
  #endif
  
  int getopt_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
  int getopt_main(int argc, char **argv)
  {
  	char *optstr = NULL;
  	char *name = NULL;
  	unsigned opt;
  	const char *compatible;
  	char *s_arg;
  #if ENABLE_GETOPT_LONG
  	struct option *long_options = NULL;
  	llist_t *l_arg = NULL;
  #endif
  
  	compatible = getenv("GETOPT_COMPATIBLE"); /* used as yes/no flag */
  
  	if (argc == 1) {
  		if (compatible) {
  			/* For some reason, the original getopt gave no error
  			   when there were no arguments. */
  			printf(" --\n");
  			return 0;
  		}
  		bb_error_msg_and_die("missing optstring argument");
  	}
  
  	if (argv[1][0] != '-' || compatible) {
  		char *s;
  
  		option_mask32 |= OPT_u; /* quoting off */
  		s = xstrdup(argv[1] + strspn(argv[1], "-+"));
  		argv[1] = argv[0];
  		return generate_output(argv+1, argc-1, s, long_options);
  	}
  
  #if !ENABLE_GETOPT_LONG
  	opt = getopt32(argv, "+o:n:qQs:Tu", &optstr, &name, &s_arg);
  #else
  	applet_long_options = getopt_longopts;
  	opt_complementary = "l::";
  	opt = getopt32(argv, "+o:n:qQs:Tual:",
  					&optstr, &name, &s_arg, &l_arg);
  	/* Effectuate the read options for the applet itself */
  	while (l_arg) {
  		long_options = add_long_options(long_options, l_arg->data);
  		l_arg = l_arg->link;
  	}
  #endif
  
  	if (opt & OPT_s) {
  		set_shell(s_arg);
  	}
  
  	if (opt & OPT_T) {
  		return 4;
  	}
  
  	/* All options controlling the applet have now been parsed */
  	if (!optstr) {
  		if (optind >= argc)
  			bb_error_msg_and_die("missing optstring argument");
  		optstr = argv[optind++];
  	}
  
  	argv[optind-1] = name ? name : argv[0];
  	return generate_output(argv+optind-1, argc-optind+1, optstr, long_options);
  }
  