linux通常使用GNU C提供的函数getopt、getopt_long、getopt_long_only函数来解析命令行参数。
移植到Windows下
getopt.h
#ifndef _GETOPT_H #define _GETOPT_H #ifdef __cplusplus extern "C" { #endif /* For communication from `getopt' to the caller. When `getopt' finds an option that takes an argument, the argument value is returned here. Also, when `ordering' is RETURN_IN_ORDER, each non-option ARGV-element is returned here.*/ extern char* optarg; /* Index in ARGV of the next element to be scanned. This is used for communication to and from the caller and for communication between successive calls to `getopt'. On entry to `getopt', zero means this is the first call; initialize. When `getopt' returns -1, this is the index of the first of the non-option elements that the caller should itself scan. Otherwise, `optind' communicates from one call to the next how much of ARGV has been scanned so far.*/ extern int optind; /* Callers store zero here to inhibit the error message `getopt' prints for unrecognized options.*/ extern int opterr; /* Set to an option character which was unrecognized.*/ extern int optopt; /* Describe the long-named options requested by the application. The LONG_OPTIONS argument to getopt_long or getopt_long_only is a vector of `struct option' terminated by an element containing a name which is zero. The field `has_arg' is: no_argument(or 0) if the option does not take an argument, required_argument(or 1) if the option requires an argument, optional_argument(or 2) if the option takes an optional argument. If the field `flag' is not NULL, it points to a variable that is set to the value given in the field `val' when the option is found, but left unchanged if the option is not found. To have a long-named option do something other than set an `int' to a compiled-in constant, such as set a value from `optarg', set the option's `flag' field to zero and its `val' field to a nonzero value (the equivalent single-letter option character, if there is one).For long options that have a zero `flag' field, `getopt' returns the contents of the `val' field.*/ struct option { #if defined (__STDC__) && __STDC__ const char* name; #else char* name; #endif /* has_arg can't be an enum because some compilers complain about type mismatches in all the code that assumes it is an int.*/ int has_arg; int* flag; int val; }; /* Names for the values of the `has_arg' field of `struct option'.*/ #define no_argument 0 #define required_argument 1 #define optional_argument 2 extern int getopt_long(int argc, char* const* argv, const char* shortopts, const struct option* longopts, int* longind); extern int getopt_long_only(int argc, char* const* argv, const char* shortopts, const struct option* longopts, int* longind); /* Internal only.Users should not call this directly.*/ extern int _getopt_internal(int argc, char* const* argv, const char* shortopts, const struct option* longopts, int* longind, int long_only); extern int getopt(int argc, char* const* argv, const char* optstring); #ifdef __cplusplus } #endif #endif /* _GETOPT_H */
getopt.cpp
#include <stdio.h> #include <stdlib.h> #include <windows.h> #define getpid() GetCurrentProcessId() #ifndef _ /* This is for other GNU distributions with internationalized messages. When compiling libc, the _ macro is predefined. */ #ifdef NEVER_HAVE_LIBINTL_H # include <libintl.h> # define _(msgid) gettext (msgid) #else # define _(msgid) (msgid) #endif #endif /* This version of `getopt' appears to the caller like standard Unix `getopt' but it behaves differently for the user, since it allows the user to intersperse the options with the other arguments. As `getopt' works, it permutes the elements of ARGV so that, when it is done, all the options precede everything else. Thus all application programs are extended to handle flexible argument order. Setting the environment variable POSIXLY_CORRECT disables permutation. Then the behavior is completely standard. GNU application programs can use a third alternative mode in which they can distinguish the relative order of options and other arguments. */ #include "getopt.h" /* For communication from `getopt' to the caller. When `getopt' finds an option that takes an argument, the argument value is returned here. Also, when `ordering' is RETURN_IN_ORDER, each non-option ARGV-element is returned here. */ char* optarg = NULL; /* Index in ARGV of the next element to be scanned. This is used for communication to and from the caller and for communication between successive calls to `getopt'. On entry to `getopt', zero means this is the first call; initialize. When `getopt' returns -1, this is the index of the first of the non-option elements that the caller should itself scan. Otherwise, `optind' communicates from one call to the next how much of ARGV has been scanned so far. */ /* 1003.2 says this must be 1 before any call. */ int optind = 1; /* Formerly, initialization of getopt depended on optind==0, which causes problems with re-calling getopt as programs generally don't know that. */ int __getopt_initialized = 0; /* The next char to be scanned in the option-element in which the last option character we returned was found. This allows us to pick up the scan where we left off. If this is zero, or a null string, it means resume the scan by advancing to the next ARGV-element. */ static char* nextchar; /* Callers store zero here to inhibit the error message for unrecognized options. */ int opterr = 1; /* Set to an option character which was unrecognized. This must be initialized on some systems to avoid linking in the system's own getopt implementation. */ int optopt = '?'; /* Describe how to deal with options that follow non-option ARGV-elements. If the caller did not specify anything, the default is REQUIRE_ORDER if the environment variable POSIXLY_CORRECT is defined, PERMUTE otherwise. REQUIRE_ORDER means don't recognize them as options; stop option processing when the first non-option is seen. This is what Unix does. This mode of operation is selected by either setting the environment variable POSIXLY_CORRECT, or using `+' as the first character of the list of option characters. PERMUTE is the default. We permute the contents of ARGV as we scan, so that eventually all the non-options are at the end. This allows options to be given in any order, even with programs that were not written to expect this. RETURN_IN_ORDER is an option available to programs that were written to expect options and other ARGV-elements in any order and that care about the ordering of the two. We describe each non-option ARGV-element as if it were the argument of an option with character code 1. Using `-' as the first character of the list of option characters selects this mode of operation. The special argument `--' forces an end of option-scanning regardless of the value of `ordering'. In the case of RETURN_IN_ORDER, only `--' can cause `getopt' to return -1 with `optind' != ARGC. */ static enum { REQUIRE_ORDER, PERMUTE, RETURN_IN_ORDER } ordering; /* Value of POSIXLY_CORRECT environment variable. */ static char* posixly_correct; /* Avoid depending on library functions or files whose names are inconsistent. */ char* getenv(); static char* my_index(const char* str, int chr) { while (*str) { if (*str == chr) return (char*)str; str++; } return 0; } /* Handle permutation of arguments. */ /* Describe the part of ARGV that contains non-options that have been skipped. `first_nonopt' is the index in ARGV of the first of them; `last_nonopt' is the index after the last of them. */ static int first_nonopt; static int last_nonopt; # define SWAP_FLAGS(ch1, ch2) /* Exchange two adjacent subsequences of ARGV. One subsequence is elements [first_nonopt,last_nonopt) which contains all the non-options that have been skipped so far. The other is elements [last_nonopt,optind), which contains all the options processed since those non-options were skipped. `first_nonopt' and `last_nonopt' are relocated so that they describe the new indices of the non-options in ARGV after they are moved. */ static void exchange(char** argv) { int bottom = first_nonopt; int middle = last_nonopt; int top = optind; char* tem; /* Exchange the shorter segment with the far end of the longer segment. That puts the shorter segment into the right place. It leaves the longer segment in the right place overall, but it consists of two parts that need to be swapped next. */ while (top > middle && middle > bottom) { if (top - middle > middle - bottom) { /* Bottom segment is the short one. */ int len = middle - bottom; register int i; /* Swap it with the top part of the top segment. */ for (i = 0; i < len; i++) { tem = argv[bottom + i]; argv[bottom + i] = argv[top - (middle - bottom) + i]; argv[top - (middle - bottom) + i] = tem; SWAP_FLAGS(bottom + i, top - (middle - bottom) + i); } /* Exclude the moved bottom segment from further swapping. */ top -= len; } else { /* Top segment is the short one. */ int len = top - middle; register int i; /* Swap it with the bottom part of the bottom segment. */ for (i = 0; i < len; i++) { tem = argv[bottom + i]; argv[bottom + i] = argv[middle + i]; argv[middle + i] = tem; SWAP_FLAGS(bottom + i, middle + i); } /* Exclude the moved top segment from further swapping. */ bottom += len; } } /* Update records for the slots the non-options now occupy. */ first_nonopt += (optind - last_nonopt); last_nonopt = optind; } /* Initialize the internal data when the first call is made. */ static const char* _getopt_initialize(int argc, char* const* argv, const char* optstring) { /* Start processing options with ARGV-element 1 (since ARGV-element 0 is the program name); the sequence of previously skipped non-option ARGV-elements is empty. */ first_nonopt = last_nonopt = optind; nextchar = NULL; // posixly_correct = getenv ("POSIXLY_CORRECT"); /* Determine how to handle the ordering of options and nonoptions. */ if (optstring[0] == '-') { ordering = RETURN_IN_ORDER; ++optstring; } else if (optstring[0] == '+') { ordering = REQUIRE_ORDER; ++optstring; } //else if (posixly_correct != NULL) // ordering = REQUIRE_ORDER; else ordering = PERMUTE; return optstring; } /* Scan elements of ARGV (whose length is ARGC) for option characters given in OPTSTRING. If an element of ARGV starts with '-', and is not exactly "-" or "--", then it is an option element. The characters of this element (aside from the initial '-') are option characters. If `getopt' is called repeatedly, it returns successively each of the option characters from each of the option elements. If `getopt' finds another option character, it returns that character, updating `optind' and `nextchar' so that the next call to `getopt' can resume the scan with the following option character or ARGV-element. If there are no more option characters, `getopt' returns -1. Then `optind' is the index in ARGV of the first ARGV-element that is not an option. (The ARGV-elements have been permuted so that those that are not options now come last.) OPTSTRING is a string containing the legitimate option characters. If an option character is seen that is not listed in OPTSTRING, return '?' after printing an error message. If you set `opterr' to zero, the error message is suppressed but we still return '?'. If a char in OPTSTRING is followed by a colon, that means it wants an arg, so the following text in the same ARGV-element, or the text of the following ARGV-element, is returned in `optarg'. Two colons mean an option that wants an optional arg; if there is text in the current ARGV-element, it is returned in `optarg', otherwise `optarg' is set to zero. If OPTSTRING starts with `-' or `+', it requests different methods of handling the non-option ARGV-elements. See the comments about RETURN_IN_ORDER and REQUIRE_ORDER, above. Long-named options begin with `--' instead of `-'. Their names may be abbreviated as long as the abbreviation is unique or is an exact match for some defined option. If they have an argument, it follows the option name in the same ARGV-element, separated from the option name by a `=', or else the in next ARGV-element. When `getopt' finds a long-named option, it returns 0 if that option's `flag' field is nonzero, the value of the option's `val' field if the `flag' field is zero. The elements of ARGV aren't really const, because we permute them. But we pretend they're const in the prototype to be compatible with other systems. LONGOPTS is a vector of `struct option' terminated by an element containing a name which is zero. LONGIND returns the index in LONGOPT of the long-named option found. It is only valid when a long-named option has been found by the most recent call. If LONG_ONLY is nonzero, '-' as well as '--' can introduce long-named options. */ int _getopt_internal(int argc, char* const* argv, const char* optstring, const struct option* longopts, int* longind, int long_only) { optarg = NULL; if (optind == 0 || !__getopt_initialized) { if (optind == 0) optind = 1; /* Don't scan ARGV[0], the program name. */ optstring = _getopt_initialize(argc, argv, optstring); __getopt_initialized = 1; } /* Test whether ARGV[optind] points to a non-option argument. Either it does not have option syntax, or there is an environment flag from the shell indicating it is not an option. The later information is only used when the used in the GNU libc. */ #define NONOPTION_P (argv[optind][0] != '-' || argv[optind][1] == ' ') if (nextchar == NULL || *nextchar == ' ') { /* Advance to the next ARGV-element. */ /* Give FIRST_NONOPT & LAST_NONOPT rational values if OPTIND has been moved back by the user (who may also have changed the arguments). */ if (last_nonopt > optind) last_nonopt = optind; if (first_nonopt > optind) first_nonopt = optind; if (ordering == PERMUTE) { /* If we have just processed some options following some non-options, exchange them so that the options come first. */ if (first_nonopt != last_nonopt && last_nonopt != optind) exchange((char**)argv); else if (last_nonopt != optind) first_nonopt = optind; /* Skip any additional non-options and extend the range of non-options previously skipped. */ while (optind < argc && NONOPTION_P) optind++; last_nonopt = optind; } /* The special ARGV-element `--' means premature end of options. Skip it like a null option, then exchange with previous non-options as if it were an option, then skip everything else like a non-option. */ if (optind != argc && !strcmp(argv[optind], "--")) { optind++; if (first_nonopt != last_nonopt && last_nonopt != optind) exchange((char**)argv); else if (first_nonopt == last_nonopt) first_nonopt = optind; last_nonopt = argc; optind = argc; } /* If we have done all the ARGV-elements, stop the scan and back over any non-options that we skipped and permuted. */ if (optind == argc) { /* Set the next-arg-index to point at the non-options that we previously skipped, so the caller will digest them. */ if (first_nonopt != last_nonopt) optind = first_nonopt; return -1; } /* If we have come to a non-option and did not permute it, either stop the scan or describe it to the caller and pass it by. */ if (NONOPTION_P) { if (ordering == REQUIRE_ORDER) return -1; optarg = argv[optind++]; return 1; } /* We have found another option-ARGV-element. Skip the initial punctuation. */ nextchar = (argv[optind] + 1 + (longopts != NULL && argv[optind][1] == '-')); } /* Decode the current option-ARGV-element. */ /* Check whether the ARGV-element is a long option. If long_only and the ARGV-element has the form "-f", where f is a valid short option, don't consider it an abbreviated form of a long option that starts with f. Otherwise there would be no way to give the -f short option. On the other hand, if there's a long option "fubar" and the ARGV-element is "-fu", do consider that an abbreviation of the long option, just like "--fu", and not "-f" with arg "u". This distinction seems to be the most useful approach. */ if (longopts != NULL && (argv[optind][1] == '-' || (long_only && (argv[optind][2] || !my_index(optstring, argv[optind][1]))))) { char* nameend; const struct option* p; const struct option* pfound = NULL; int exact = 0; int ambig = 0; int indfound = -1; int option_index; for (nameend = nextchar; *nameend && *nameend != '='; nameend++) /* Do nothing. */; /* Test all long options for either exact match or abbreviated matches. */ for (p = longopts, option_index = 0; p->name; p++, option_index++) if (!strncmp(p->name, nextchar, nameend - nextchar)) { if ((unsigned int)(nameend - nextchar) == (unsigned int)strlen(p->name)) { /* Exact match found. */ pfound = p; indfound = option_index; exact = 1; break; } else if (pfound == NULL) { /* First nonexact match found. */ pfound = p; indfound = option_index; } else /* Second or later nonexact match found. */ ambig = 1; } if (ambig && !exact) { if (opterr) fprintf(stderr, _("%s: option `%s' is ambiguous "), argv[0], argv[optind]); nextchar += strlen(nextchar); optind++; optopt = 0; return '?'; } if (pfound != NULL) { option_index = indfound; optind++; if (*nameend) { /* Don't test has_arg with >, because some C compilers don't allow it to be used on enums. */ if (pfound->has_arg) optarg = nameend + 1; else { if (opterr) if (argv[optind - 1][1] == '-') /* --option */ fprintf(stderr, _ ("%s: option `--%s' doesn't allow an argument "), argv[0], pfound->name); else /* +option or -option */ fprintf(stderr, _ ("%s: option `%c%s' doesn't allow an argument "), argv[0], argv[optind - 1][0], pfound->name); nextchar += strlen(nextchar); optopt = pfound->val; return '?'; } } else if (pfound->has_arg == 1) { if (optind < argc) optarg = argv[optind++]; else { if (opterr) fprintf(stderr, _("%s: option `%s' requires an argument "), argv[0], argv[optind - 1]); nextchar += strlen(nextchar); optopt = pfound->val; return optstring[0] == ':' ? ':' : '?'; } } nextchar += strlen(nextchar); if (longind != NULL) *longind = option_index; if (pfound->flag) { *(pfound->flag) = pfound->val; return 0; } return pfound->val; } /* Can't find it as a long option. If this is not getopt_long_only, or the option starts with '--' or is not a valid short option, then it's an error. Otherwise interpret it as a short option. */ if (!long_only || argv[optind][1] == '-' || my_index(optstring, *nextchar) == NULL) { if (opterr) { if (argv[optind][1] == '-') /* --option */ fprintf(stderr, _("%s: unrecognized option `--%s' "), argv[0], nextchar); else /* +option or -option */ fprintf(stderr, _("%s: unrecognized option `%c%s' "), argv[0], argv[optind][0], nextchar); } nextchar = (char*)""; optind++; optopt = 0; return '?'; } } /* Look at and handle the next short option-character. */ { char c = *nextchar++; char* temp = my_index(optstring, c); /* Increment `optind' when we start to process its last character. */ if (*nextchar == ' ') ++optind; if (temp == NULL || c == ':') { if (opterr) { if (posixly_correct) /* 1003.2 specifies the format of this message. */ fprintf(stderr, _("%s: illegal option -- %c "), argv[0], c); else fprintf(stderr, _("%s: invalid option -- %c "), argv[0], c); } optopt = c; return '?'; } /* Convenience. Treat POSIX -W foo same as long option --foo */ if (temp[0] == 'W' && temp[1] == ';') { char* nameend; const struct option* p; const struct option* pfound = NULL; int exact = 0; int ambig = 0; int indfound = 0; int option_index; /* This is an option that requires an argument. */ if (*nextchar != ' ') { optarg = nextchar; /* If we end this ARGV-element by taking the rest as an arg, we must advance to the next element now. */ optind++; } else if (optind == argc) { if (opterr) { /* 1003.2 specifies the format of this message. */ fprintf(stderr, _("%s: option requires an argument -- %c "), argv[0], c); } optopt = c; if (optstring[0] == ':') c = ':'; else c = '?'; return c; } else /* We already incremented `optind' once; increment it again when taking next ARGV-elt as argument. */ optarg = argv[optind++]; /* optarg is now the argument, see if it's in the table of longopts. */ for (nextchar = nameend = optarg; *nameend && *nameend != '='; nameend++) /* Do nothing. */; /* Test all long options for either exact match or abbreviated matches. */ for (p = longopts, option_index = 0; p->name; p++, option_index++) if (!strncmp(p->name, nextchar, nameend - nextchar)) { if ((unsigned int)(nameend - nextchar) == strlen(p->name)) { /* Exact match found. */ pfound = p; indfound = option_index; exact = 1; break; } else if (pfound == NULL) { /* First nonexact match found. */ pfound = p; indfound = option_index; } else /* Second or later nonexact match found. */ ambig = 1; } if (ambig && !exact) { if (opterr) fprintf(stderr, _("%s: option `-W %s' is ambiguous "), argv[0], argv[optind]); nextchar += strlen(nextchar); optind++; return '?'; } if (pfound != NULL) { option_index = indfound; if (*nameend) { /* Don't test has_arg with >, because some C compilers don't allow it to be used on enums. */ if (pfound->has_arg) optarg = nameend + 1; else { if (opterr) fprintf(stderr, _("\%s: option `-W %s' doesn't allow an argument "), argv[0], pfound->name); nextchar += strlen(nextchar); return '?'; } } else if (pfound->has_arg == 1) { if (optind < argc) optarg = argv[optind++]; else { if (opterr) fprintf(stderr, _("%s: option `%s' requires an argument "), argv[0], argv[optind - 1]); nextchar += strlen(nextchar); return optstring[0] == ':' ? ':' : '?'; } } nextchar += strlen(nextchar); if (longind != NULL) *longind = option_index; if (pfound->flag) { *(pfound->flag) = pfound->val; return 0; } return pfound->val; } nextchar = NULL; return 'W'; /* Let the application handle it. */ } if (temp[1] == ':') { if (temp[2] == ':') { /* This is an option that accepts an argument optionally. */ if (*nextchar != ' ') { optarg = nextchar; optind++; } else optarg = NULL; nextchar = NULL; } else { /* This is an option that requires an argument. */ if (*nextchar != ' ') { optarg = nextchar; /* If we end this ARGV-element by taking the rest as an arg, we must advance to the next element now. */ optind++; } else if (optind == argc) { if (opterr) { /* 1003.2 specifies the format of this message. */ fprintf(stderr, _("%s: option requires an argument -- %c "), argv[0], c); } optopt = c; if (optstring[0] == ':') c = ':'; else c = '?'; } else /* We already incremented `optind' once; increment it again when taking next ARGV-elt as argument. */ optarg = argv[optind++]; nextchar = NULL; } } return c; } } int getopt(int argc, char* const* argv, const char* optstring) { return _getopt_internal(argc, argv, optstring, (const struct option*)0, (int*)0, 0); } int getopt_long( int argc, char* const* argv, const char* options, const struct option* long_options, int* opt_index) { return _getopt_internal(argc, argv, options, long_options, opt_index, 0); } /* Like getopt_long, but '-' as well as '--' can indicate a long option. If an option that starts with '-' (not '--') doesn't match a long option, but does match a short option, it is parsed as a short option instead. */ int getopt_long_only( int argc, char* const* argv, const char* options, const struct option* long_options, int* opt_index) { return _getopt_internal(argc, argv, options, long_options, opt_index, 1); }
getopt_long函数的使用：