vg_opt.h

   1 /*
   2  * Copyright (C) 2021-2022 Mt.ZERO Software, Harry Godden - All Rights Reserved
   3  */
   4
   5 #ifndef VG_OPT_H
   6 #define VG_OPT_H
   7
   8 #include <stdlib.h>
   9 #include "vg_platform.h"
  10 #include "vg_log.h"
  11
  12 /*
  13  * Supported:
  14  *   short flags       |  -abc
  15  *   short options     |  -a value
  16  *   multi-set options |  -ab value
  17  *
  18  *   long gnu options  |  --long-value=test
  19  *   standard agument  |  regular_thing
  20  */
  21
  22 static int vg_argi = 1;
  23 static int vg_argj = 1;
  24 static int vg_argc = 0;
  25 static int vg_consume_next = 0;
  26 static char **vg_argv;
  27
  28 /* Will return 0 if exhausted */
  29 int vg_argp( int argc, char *argv[] )
  30 {
  31    vg_argv = argv;
  32    vg_argc = argc;
  33
  34    static int delta_i = 0;
  35    static int delta_j = 0;
  36
  37    if( vg_argj != 1 && !vg_argv[ vg_argi ][ vg_argj ] )
  38    {
  39       vg_argj = 1;
  40       vg_argi ++;
  41    }
  42
  43    if( vg_consume_next )
  44    {
  45       vg_consume_next = 0;
  46       vg_argi ++;
  47    }
  48
  49    if( vg_argi >= argc )
  50       return 0;
  51
  52    if( (delta_i == vg_argi) && (delta_j == vg_argj) )
  53    {
  54       char *cur = &vg_argv[ vg_argi ][ vg_argj ];
  55
  56       if( *cur != '-' )
  57       {
  58          vg_error( "Unknown opt '-%c'\n", *cur );
  59       }
  60       else
  61       {
  62          vg_error( "Unknown opt '--%s'\n", cur + 1 );
  63       }
  64
  65       exit(0);
  66    }
  67
  68    delta_i = vg_argi;
  69    delta_j = vg_argj;
  70
  71    return 1;
  72 }
  73
  74 /* Example: see if -c is set */
  75 int vg_opt( char c )
  76 {
  77    char *carg = vg_argv[ vg_argi ];
  78
  79    if( carg[0] == '-' )
  80    {
  81       if( carg[1] == '-' )
  82          return 0;
  83
  84       if( carg[ vg_argj ] == c )
  85       {
  86          vg_argj ++;
  87
  88          return 1;
  89       }
  90    }
  91
  92    return 0;
  93 }
  94
  95 /* Example: get -c *value* */
  96 char *vg_opt_arg( char c )
  97 {
  98    if( vg_opt( c ) )
  99    {
 100       if( vg_argi < vg_argc-1 )
 101       {
 102          if( vg_argv[ vg_argi + 1 ][0] != '-' )
 103          {
 104             vg_consume_next = 1;
 105             return vg_argv[ vg_argi + 1 ];
 106          }
 107       }
 108
 109       vg_error( "Option '%c' requires argument!\n", c );
 110       exit(0);
 111    }
 112
 113    return NULL;
 114 }
 115
 116 /* Example see if --big is set */
 117 int vg_long_opt( char *name )
 118 {
 119    char *carg = vg_argv[ vg_argi ];
 120
 121    if( carg[0] == '-' )
 122    {
 123       if( carg[1] == '-' )
 124       {
 125          if( !strcmp( name, carg+2 ) )
 126          {
 127             vg_consume_next = 1;
 128             return 1;
 129          }
 130       }
 131    }
 132
 133    return 0;
 134 }
 135
 136 /* Example: get --big=value */
 137 char *vg_long_opt_arg( char *name )
 138 {
 139    char *carg = vg_argv[ vg_argi ];
 140
 141    if( carg[0] == '-' )
 142    {
 143       if( carg[1] == '-' )
 144       {
 145          int k = 2; int set = 0;
 146          while( carg[ k ] )
 147          {
 148             if( carg[ k ] == '=' )
 149             {
 150                set = 1;
 151                break;
 152             }
 153
 154             k ++;
 155          }
 156
 157          if( !strncmp( name, carg+2, k-2 ) )
 158          {
 159             vg_consume_next = 1;
 160
 161             // the rest
 162             if( set )
 163             {
 164                return carg + k + 1;
 165             }
 166             else
 167             {
 168                vg_error( "Long option '%s' requires argument\n", name );
 169             }
 170          }
 171       }
 172    }
 173
 174    return NULL;
 175 }
 176
 177 /* Example: get regular_thing */
 178 char *vg_arg(void)
 179 {
 180    char *carg = vg_argv[ vg_argi ];
 181
 182    if( carg[0] != '-' )
 183    {
 184       vg_consume_next = 1;
 185       return carg;
 186    }
 187
 188    return NULL;
 189 }
 190
 191 #endif