contrib/flex/scanopt.h

   1 /* flex - tool to generate fast lexical analyzers */
   2
   3 /*  Copyright (c) 1990 The Regents of the University of California. */
   4 /*  All rights reserved. */
   5
   6 /*  This code is derived from software contributed to Berkeley by */
   7 /*  Vern Paxson. */
   8
   9 /*  The United States Government has rights in this work pursuant */
  10 /*  to contract no. DE-AC03-76SF00098 between the United States */
  11 /*  Department of Energy and the University of California. */
  12
  13 /*  This file is part of flex. */
  14
  15 /*  Redistribution and use in source and binary forms, with or without */
  16 /*  modification, are permitted provided that the following conditions */
  17 /*  are met: */
  18
  19 /*  1. Redistributions of source code must retain the above copyright */
  20 /*     notice, this list of conditions and the following disclaimer. */
  21 /*  2. Redistributions in binary form must reproduce the above copyright */
  22 /*     notice, this list of conditions and the following disclaimer in the */
  23 /*     documentation and/or other materials provided with the distribution. */
  24
  25 /*  Neither the name of the University nor the names of its contributors */
  26 /*  may be used to endorse or promote products derived from this software */
  27 /*  without specific prior written permission. */
  28
  29 /*  THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR */
  30 /*  IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED */
  31 /*  WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR */
  32 /*  PURPOSE. */
  33 \f
  34 #ifndef SCANOPT_H
  35 #define SCANOPT_H
  36
  37 #include "flexdef.h"
  38
  39
  40 #ifndef NO_SCANOPT_USAGE
  41 /* Used by scanopt_usage for pretty-printing. */
  42 #ifdef HAVE_NCURSES_H
  43 #include <ncurses.h>
  44 #endif
  45 #endif
  46
  47 #ifdef __cplusplus
  48 extern  "C" {
  49 #endif
  50 #ifndef PROTO
  51 #define PROTO(args) args
  52 #endif
  53 /* Error codes. */ enum scanopt_err_t {
  54                 SCANOPT_ERR_OPT_UNRECOGNIZED = -1,      /* Unrecognized option. */
  55                 SCANOPT_ERR_OPT_AMBIGUOUS = -2, /* It matched more than one option name. */
  56                 SCANOPT_ERR_ARG_NOT_FOUND = -3, /* The required arg was not found. */
  57                 SCANOPT_ERR_ARG_NOT_ALLOWED = -4        /* Option does not take an argument. */
  58         };
  59
  60
  61 /* flags passed to scanopt_init */
  62         enum scanopt_flag_t {
  63                 SCANOPT_NO_ERR_MSG = 0x01       /* Suppress printing to stderr. */
  64         };
  65
  66 /* Specification for a single option. */
  67         struct optspec_t {
  68                 const char *opt_fmt;    /* e.g., "--foo=FILE", "-f FILE", "-n [NUM]" */
  69                 int     r_val;  /* Value to be returned by scanopt_ex(). */
  70                 const char *desc;       /* Brief description of this option, or NULL. */
  71         };
  72         typedef struct optspec_t optspec_t;
  73
  74
  75 /* Used internally by scanopt() to maintain state. */
  76 /* Never modify these value directly. */
  77         typedef void *scanopt_t;
  78 \f
  79
  80 /* Initializes scanner and checks option list for errors.
  81  * Parameters:
  82  *   options - Array of options.
  83  *   argc    - Same as passed to main().
  84  *   argv    - Same as passed to main(). First element is skipped.
  85  *   flags   - Control behavior.
  86  * Return:  A malloc'd pointer .
  87  */
  88         scanopt_t *scanopt_init PROTO ((const optspec_t * options,
  89                                         int argc, char **argv, int flags));
  90
  91 /* Frees memory used by scanner.
  92  * Always returns 0. */
  93         int scanopt_destroy PROTO ((scanopt_t * scanner));
  94
  95 #ifndef NO_SCANOPT_USAGE
  96 /* Prints a usage message based on contents of optlist.
  97  * Parameters:
  98  *   scanner  - The scanner, already initialized with scanopt_init().
  99  *   fp       - The file stream to write to.
 100  *   usage    - Text to be prepended to option list. May be NULL.
 101  * Return:  Always returns 0 (zero).
 102  */
 103         int scanopt_usage
 104                 PROTO (
 105                        (scanopt_t * scanner, FILE * fp,
 106                         const char *usage));
 107 #endif
 108
 109 /* Scans command-line options in argv[].
 110  * Parameters:
 111  *   scanner  - The scanner, already initialized with scanopt_init().
 112  *   optarg   - Return argument, may be NULL.
 113  *              On success, it points to start of an argument.
 114  *   optindex - Return argument, may be NULL.
 115  *              On success or failure, it is the index of this option.
 116  *              If return is zero, then optindex is the NEXT valid option index.
 117  *
 118  * Return:  > 0 on success. Return value is from optspec_t->rval.
 119  *         == 0 if at end of options.
 120  *          < 0 on error (return value is an error code).
 121  *
 122  */
 123         int scanopt
 124                 PROTO (
 125                        (scanopt_t * scanner, char **optarg,
 126                         int *optindex));
 127
 128 #ifdef __cplusplus
 129 }
 130 #endif
 131 #endif
 132 /* vim:set tabstop=8 softtabstop=4 shiftwidth=4: */