getopt_long.c raw

   1  #define _GNU_SOURCE
   2  #include <stddef.h>
   3  #include <stdlib.h>
   4  #include <limits.h>
   5  #include <getopt.h>
   6  #include <stdio.h>
   7  #include <string.h>
   8  #include "stdio_impl.h"
   9  
  10  extern int __optpos, __optreset;
  11  
  12  static void permute(char *const *argv, int dest, int src)
  13  {
  14  	char **av = (char **)argv;
  15  	char *tmp = av[src];
  16  	int i;
  17  	for (i=src; i>dest; i--)
  18  		av[i] = av[i-1];
  19  	av[dest] = tmp;
  20  }
  21  
  22  static int __getopt_long_core(int argc, char *const *argv, const char *optstring, const struct option *longopts, int *idx, int longonly);
  23  
  24  static int __getopt_long(int argc, char *const *argv, const char *optstring, const struct option *longopts, int *idx, int longonly)
  25  {
  26  	int ret, skipped, resumed;
  27  	if (!optind || __optreset) {
  28  		__optreset = 0;
  29  		__optpos = 0;
  30  		optind = 1;
  31  	}
  32  	if (optind >= argc || !argv[optind]) return -1;
  33  	skipped = optind;
  34  	if (optstring[0] != '+' && optstring[0] != '-') {
  35  		int i;
  36  		for (i=optind; ; i++) {
  37  			if (i >= argc || !argv[i]) return -1;
  38  			if (argv[i][0] == '-' && argv[i][1]) break;
  39  		}
  40  		optind = i;
  41  	}
  42  	resumed = optind;
  43  	ret = __getopt_long_core(argc, argv, optstring, longopts, idx, longonly);
  44  	if (resumed > skipped) {
  45  		int i, cnt = optind-resumed;
  46  		for (i=0; i<cnt; i++)
  47  			permute(argv, skipped, optind-1);
  48  		optind = skipped + cnt;
  49  	}
  50  	return ret;
  51  }
  52  
  53  static int __getopt_long_core(int argc, char *const *argv, const char *optstring, const struct option *longopts, int *idx, int longonly)
  54  {
  55  	optarg = 0;
  56  	if (longopts && argv[optind][0] == '-' &&
  57  		((longonly && argv[optind][1] && argv[optind][1] != '-') ||
  58  		 (argv[optind][1] == '-' && argv[optind][2])))
  59  	{
  60  		int colon = optstring[optstring[0]=='+'||optstring[0]=='-']==':';
  61  		int i, cnt, match;
  62  		char *arg, *opt, *start = argv[optind]+1;
  63  		for (cnt=i=0; longopts[i].name; i++) {
  64  			const char *name = longopts[i].name;
  65  			opt = start;
  66  			if (*opt == '-') opt++;
  67  			while (*opt && *opt != '=' && *opt == *name)
  68  				name++, opt++;
  69  			if (*opt && *opt != '=') continue;
  70  			arg = opt;
  71  			match = i;
  72  			if (!*name) {
  73  				cnt = 1;
  74  				break;
  75  			}
  76  			cnt++;
  77  		}
  78  		if (cnt==1 && longonly && arg-start == mblen(start, MB_LEN_MAX)) {
  79  			int l = arg-start;
  80  			for (i=0; optstring[i]; i++) {
  81  				int j;
  82  				for (j=0; j<l && start[j]==optstring[i+j]; j++);
  83  				if (j==l) {
  84  					cnt++;
  85  					break;
  86  				}
  87  			}
  88  		}
  89  		if (cnt==1) {
  90  			i = match;
  91  			opt = arg;
  92  			optind++;
  93  			if (*opt == '=') {
  94  				if (!longopts[i].has_arg) {
  95  					optopt = longopts[i].val;
  96  					if (colon || !opterr)
  97  						return '?';
  98  					__getopt_msg(argv[0],
  99  						": option does not take an argument: ",
 100  						longopts[i].name,
 101  						strlen(longopts[i].name));
 102  					return '?';
 103  				}
 104  				optarg = opt+1;
 105  			} else if (longopts[i].has_arg == required_argument) {
 106  				if (!(optarg = argv[optind])) {
 107  					optopt = longopts[i].val;
 108  					if (colon) return ':';
 109  					if (!opterr) return '?';
 110  					__getopt_msg(argv[0],
 111  						": option requires an argument: ",
 112  						longopts[i].name,
 113  						strlen(longopts[i].name));
 114  					return '?';
 115  				}
 116  				optind++;
 117  			}
 118  			if (idx) *idx = i;
 119  			if (longopts[i].flag) {
 120  				*longopts[i].flag = longopts[i].val;
 121  				return 0;
 122  			}
 123  			return longopts[i].val;
 124  		}
 125  		if (argv[optind][1] == '-') {
 126  			optopt = 0;
 127  			if (!colon && opterr)
 128  				__getopt_msg(argv[0], cnt ?
 129  					": option is ambiguous: " :
 130  					": unrecognized option: ",
 131  					argv[optind]+2,
 132  					strlen(argv[optind]+2));
 133  			optind++;
 134  			return '?';
 135  		}
 136  	}
 137  	return getopt(argc, argv, optstring);
 138  }
 139  
 140  int getopt_long(int argc, char *const *argv, const char *optstring, const struct option *longopts, int *idx)
 141  {
 142  	return __getopt_long(argc, argv, optstring, longopts, idx, 0);
 143  }
 144  
 145  int getopt_long_only(int argc, char *const *argv, const char *optstring, const struct option *longopts, int *idx)
 146  {
 147  	return __getopt_long(argc, argv, optstring, longopts, idx, 1);
 148  }
 149