/*
    getopt.c - Enhanced implementation of BSD getopt(1)
    Copyright (c) 1997, 1998, 1999, 2000  Frodo Looijaard <frodol@dds.nl>

    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; either version 2 of the License, or
    (at your option) any later version.

    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.

    You should have received a copy of the GNU General Public License
    along with this program; if not, write to the Free Software
    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/

/* 
 * 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
 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <ctype.h>

#if LIBCGETOPT
#include <getopt.h>
#else
#include "getopt.h"
#endif

#define _(x) x

/* NON_OPT is the code that is returned when a non-option is found in '+' 
   mode */
#define NON_OPT 1
/* LONG_OPT is the code that is returned when a long option is found. */
#define LONG_OPT 2

/* The shells recognized. */
typedef enum {BASH,TCSH} shell_t;


/* Some global variables that tells us how to parse. */
shell_t shell=BASH; /* The shell we generate output for. */
int quiet_errors=0; /* 0 is not quiet. */
int quiet_output=0; /* 0 is not quiet. */
int quote=1; /* 1 is do quote. */
#ifdef HAVE_GETOPT_LONG_ONLY
int alternative=0; /* 0 is getopt_long, 1 is getopt_long_only */
#endif

/* Function prototypes */
void *our_malloc(size_t size);
void *our_realloc(void *ptr, size_t size);
const char *normalize(const char *arg);
int generate_output(char * argv[],int argc,const char *optstr,
                    const struct option *longopts);
int main(int argc, char *argv[]);
void parse_error(const char *message);
void add_long_options(char *options);
void add_longopt(const char *name,int has_arg);
void print_help(void);
void set_shell(const char *new_shell);
void set_initial_shell(void);

void *our_malloc(size_t size)
{
	void *ret=malloc(size);
	if (! ret) {
		fprintf(stderr,_("%s: Out of memory!\n"),"getopt");
		exit(3);
	}
	return(ret);
}

void *our_realloc(void *ptr, size_t size)
{
	void *ret=realloc(ptr,size);
	if (! ret && size) {
		fprintf(stderr,_("%s: Out of memory!\n"),"getopt");
		exit(3);
	}
	return(ret);
}

/*
 * 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.
 */
const char *normalize(const char *arg)
{
	static char *BUFFER=NULL;
	const char *argptr=arg;
	char *bufptr;

	if (BUFFER != NULL)
		free(BUFFER);

	if (!quote) { /* Just copy arg */
		BUFFER=our_malloc(strlen(arg)+1);
			
		strcpy(BUFFER,arg);
		return BUFFER;
	}

	/* Each character in arg may take upto 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=our_malloc(strlen(arg)*4+3);

	bufptr=BUFFER;
	*bufptr++='\'';

	while (*argptr) {
		if (*argptr == '\'') {
			/* Quote: replace it with: '\'' */
			*bufptr++='\'';
			*bufptr++='\\';
			*bufptr++='\'';
			*bufptr++='\'';
		} else if (shell==TCSH && *argptr=='!') {
			/* Exclamation mark: replace it with: \! */
			*bufptr++='\'';
			*bufptr++='\\';
			*bufptr++='!';
			*bufptr++='\'';
		} else if (shell==TCSH && *argptr=='\n') {
			/* Newline: replace it with: \n */
			*bufptr++='\\';
			*bufptr++='n';
		} else if (shell==TCSH && isspace(*argptr)) {
			/* Non-newline whitespace: replace it with \<ws> */
			*bufptr++='\'';
			*bufptr++='\\';
			*bufptr++=*argptr;
			*bufptr++='\'';
		} else
			/* Just copy */
			*bufptr++=*argptr;
		argptr++;
	}
	*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.
 */
int generate_output(char * argv[],int argc,const char *optstr,
                    const struct option *longopts)
{
	int exit_code = 0; /* We assume everything will be OK */
	int opt;
	int longindex;
	const char *charptr;

	if (quiet_errors) /* No error reporting from getopt(3) */
		opterr=0;
	optind=0; /* Reset getopt(3) */

#ifdef HAVE_GETOPT_LONG_ONLY
	while ((opt = (alternative?
	              getopt_long_only(argc,argv,optstr,longopts,&longindex):
#else
	while ((opt = (
#endif
                      getopt_long(argc,argv,optstr,longopts,&longindex))) 
               != EOF) 
		if (opt == '?' || opt == ':' )
			exit_code = 1;
		else if (!quiet_output) 
		{
			if (opt == LONG_OPT) {
				printf(" --%s",longopts[longindex].name);
				if (longopts[longindex].has_arg) 
					printf(" %s",
					       normalize(optarg?optarg:""));
			} else 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++]));
		printf("\n");
	}
	return exit_code;
}

/*
 * Report an error when parsing getopt's own arguments.
 * If message is NULL, we already sent a message, we just exit with a helpful
 * hint.
 */
void parse_error(const char *message)
{
	if (message)
		fprintf(stderr,"getopt: %s\n",message);
	fputs(_("Try `getopt --help' for more information.\n"),stderr);
	exit(2);
}

static struct option *long_options=NULL;
static int long_options_length=0; /* Length of array */
static int long_options_nr=0; /* Nr of used elements in array */
#define LONG_OPTIONS_INCR 10
#define init_longopt() add_longopt(NULL,0)

/* Register a long option. The contents of name is copied. */
void add_longopt(const char *name,int has_arg)
{
	char *tmp;
	if (!name) { /* init */
		free(long_options);
		long_options=NULL;
		long_options_length=0;
		long_options_nr=0;
	}

	if (long_options_nr == long_options_length) {
		long_options_length += LONG_OPTIONS_INCR;
		long_options=our_realloc(long_options,
		                         sizeof(struct option) * 
		                           long_options_length);
	}

	long_options[long_options_nr].name=NULL;
	long_options[long_options_nr].has_arg=0;
	long_options[long_options_nr].flag=NULL;
	long_options[long_options_nr].val=0;

	if (long_options_nr) { /* Not for init! */
		long_options[long_options_nr-1].has_arg=has_arg;
		long_options[long_options_nr-1].flag=NULL;
		long_options[long_options_nr-1].val=LONG_OPT;
		tmp = our_malloc(strlen(name)+1);
		strcpy(tmp,name);
		long_options[long_options_nr-1].name=tmp;
	}
	long_options_nr++;
}
	

/* 
 * Register several long options. options is a string of long options, 
 * separated by commas or whitespace. 
 * This nukes options! 
 */
void add_long_options(char *options)
{
	int arg_opt;
	char *tokptr=strtok(options,", \t\n");
	while (tokptr) {
		arg_opt=no_argument;
		if (strlen(tokptr) > 0) {
			if (tokptr[strlen(tokptr)-1] == ':') {
				if (tokptr[strlen(tokptr)-2] == ':') {
					tokptr[strlen(tokptr)-2]='\0';
					arg_opt=optional_argument;
				} else {
					tokptr[strlen(tokptr)-1]='\0';
					arg_opt=required_argument;
				}
				if (strlen(tokptr) == 0)
					parse_error(_("empty long option after "
					              "-l or --long argument"));
			}
			add_longopt(tokptr,arg_opt);
		}
		tokptr=strtok(NULL,", \t\n");
	}
}

void set_shell(const char *new_shell)
{
	if (!strcmp(new_shell,"bash"))
		shell=BASH;
	else if (!strcmp(new_shell,"tcsh"))
		shell=TCSH;
	else if (!strcmp(new_shell,"sh"))
		shell=BASH;
	else if (!strcmp(new_shell,"csh"))
		shell=TCSH;
	else
		parse_error(_("unknown shell after -s or --shell argument"));
}

void print_help(void)
{
	fputs(_("Usage: getopt optstring parameters\n"),stderr);
	fputs(_("       getopt [options] [--] optstring parameters\n"),stderr);
	fputs(_("       getopt [options] -o|--options optstring [options] [--]\n"),stderr);
	fputs(_("              parameters\n"),stderr);
#ifdef HAVE_GETOPT_LONG_ONLY
	fputs(_("  -a, --alternative            Allow long options starting with single -\n"),stderr);
#endif
	fputs(_("  -h, --help                   This small usage guide\n"),stderr);
	fputs(_("  -l, --longoptions=longopts   Long options to be recognized\n"),stderr);
	fputs(_("  -n, --name=progname          The name under which errors are reported\n"),stderr);
	fputs(_("  -o, --options=optstring      Short options to be recognized\n"),stderr);
	fputs(_("  -q, --quiet                  Disable error reporting by getopt(3)\n"),stderr);
	fputs(_("  -Q, --quiet-output           No normal output\n"),stderr);
	fputs(_("  -s, --shell=shell            Set shell quoting conventions\n"),stderr);	
	fputs(_("  -T, --test                   Test for getopt(1) version\n"),stderr);
	fputs(_("  -u, --unqote                 Do not quote the output\n"),stderr);
	fputs(_("  -V, --version                Output version information\n"),stderr);
	exit(2);
}
	
/* Exit codes:
 *   0) No errors, succesful 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
 */

static struct option longopts[]={ {"options",required_argument,NULL,'o'},
                                  {"longoptions",required_argument,NULL,'l'},
                                  {"quiet",no_argument,NULL,'q'},
                                  {"quiet-output",no_argument,NULL,'Q'},
                                  {"shell",required_argument,NULL,'s'},
                                  {"test",no_argument,NULL,'T'},
                                  {"unquoted",no_argument,NULL,'u'},
                                  {"help",no_argument,NULL,'h'},
#ifdef HAVE_GETOPT_LONG_ONLY
                                  {"alternative",no_argument,NULL,'a'},
#endif
                                  {"name",required_argument,NULL,'n'},
                                  {"version",no_argument,NULL,'V'},
                                  {NULL,0,NULL,0}
                                };

/* Stop scanning as soon as a non-option argument is found! */
static const char *shortopts="+ao:l:n:qQs:TuhV";

int main(int argc, char *argv[])
{
	char *optstr=NULL;
	char *name=NULL;
	int opt;
	int compatible=0;

	init_longopt();

	if (getenv("GETOPT_COMPATIBLE")) 
		compatible=1;

	if (argc == 1) 
	{
		if (compatible) {
			/* For some reason, the original getopt gave no error
                           when there were no arguments. */
			printf(" --\n");
			exit(0);
		}
		else
			parse_error(_("missing optstring argument"));
	}
	
	if (argv[1][0] != '-' || compatible) {
		quote=0;
		optstr=our_malloc(strlen(argv[1])+1);
		strcpy(optstr,argv[1]+strspn(argv[1],"-+"));
		argv[1]=argv[0];
		exit(generate_output(argv+1,argc-1,optstr,long_options));
	}
	
	while ((opt=getopt_long(argc,argv,shortopts,longopts,NULL)) != EOF) 
		switch (opt) {
#ifdef HAVE_GETOPT_LONG_ONLY
		case 'a':
			alternative=1;
			break;
#endif
		case 'h':
			print_help();
			exit(0);
		case 'o':
			if (optstr)
				free(optstr);
			optstr=our_malloc(strlen(optarg)+1);
			strcpy(optstr,optarg);
			break;
		case 'l':
			add_long_options(optarg);
			break;
		case 'n':
			if (name)
				free(name);
			name=our_malloc(strlen(optarg)+1);
			strcpy(name,optarg);
			break;
		case 'q':
			quiet_errors=1;
			break;
		case 'Q':
			quiet_output=1;
			break;
		case 's':
			set_shell(optarg);
			break;
		case 'T':
			exit(4);
		case 'u':
			quote=0;
			break;
		case 'V':
			printf(_("getopt (enhanced) 1.1.2\n"));
			exit(0);
		case '?':
		case ':':
			parse_error(NULL);
		default:
			parse_error(_("internal error, contact the author."));
		}
	
	if (!optstr) 
	{
		if (optind >= argc)
			parse_error(_("missing optstring argument"));
		else {
			optstr=our_malloc(strlen(argv[optind])+1);
			strcpy(optstr,argv[optind]);
			optind++;
		}
	}
	if (name)
		argv[optind-1]=name;
	else
		argv[optind-1]=argv[0];
	exit(generate_output(argv+optind-1,argc-optind+1,optstr,long_options));
}