vg_opt.c

   1 /*
   2  * Copyright (C) 2021-2024 Mt.ZERO Software, Harry Godden - All Rights Reserved
   3  */
   4
   5 #include "vg_opt.h"
   6 #include "vg_platform.h"
   7 #include "vg_log.h"
   8 #include <stdlib.h>
   9
  10 /*
  11  * Supported:
  12  *   short flags       |  -abc
  13  *   short options     |  -a value
  14  *   multi-set options |  -ab value
  15  *
  16  *   long gnu options  |  --long-value=test
  17  *   standard agument  |  regular_thing
  18  */
  19
  20 static int vg_argi = 1;
  21 static int vg_argj = 1;
  22 static int vg_argc = 0;
  23 static int vg_consume_next = 0;
  24 static char **vg_argv;
  25
  26 /* Will return 0 if exhausted */
  27 int vg_argp( int argc, char *argv[] )
  28 {
  29    vg_argv = argv;
  30    vg_argc = argc;
  31
  32    static int delta_i = 0;
  33    static int delta_j = 0;
  34
  35    if( vg_argj != 1 && !vg_argv[ vg_argi ][ vg_argj ] )
  36    {
  37       vg_argj = 1;
  38       vg_argi ++;
  39    }
  40
  41    if( vg_consume_next )
  42    {
  43       vg_consume_next = 0;
  44       vg_argi ++;
  45    }
  46
  47    if( vg_argi >= argc )
  48       return 0;
  49
  50    if( (delta_i == vg_argi) && (delta_j == vg_argj) )
  51    {
  52       char *cur = &vg_argv[ vg_argi ][ vg_argj ];
  53
  54       if( *cur != '-' )
  55       {
  56          vg_error( "Unknown opt '-%c'\n", *cur );
  57       }
  58       else
  59       {
  60          vg_error( "Unknown opt '--%s'\n", cur + 1 );
  61       }
  62
  63       exit(0);
  64    }
  65
  66    delta_i = vg_argi;
  67    delta_j = vg_argj;
  68
  69    return 1;
  70 }
  71
  72 /* Example: see if -c is set */
  73 int vg_opt( char c )
  74 {
  75    char *carg = vg_argv[ vg_argi ];
  76
  77    if( carg[0] == '-' )
  78    {
  79       if( carg[1] == '-' )
  80          return 0;
  81
  82       if( carg[ vg_argj ] == c )
  83       {
  84          vg_argj ++;
  85
  86          return 1;
  87       }
  88    }
  89
  90    return 0;
  91 }
  92
  93 /* Example: get -c *value* */
  94 char *vg_opt_arg( char c )
  95 {
  96    if( vg_opt( c ) )
  97    {
  98       if( vg_argi < vg_argc-1 )
  99       {
 100          if( vg_argv[ vg_argi + 1 ][0] != '-' )
 101          {
 102             vg_consume_next = 1;
 103             return vg_argv[ vg_argi + 1 ];
 104          }
 105       }
 106
 107       vg_error( "Option '%c' requires argument!\n", c );
 108       exit(0);
 109    }
 110
 111    return NULL;
 112 }
 113
 114 /* Example see if --big is set */
 115 int vg_long_opt( char *name )
 116 {
 117    char *carg = vg_argv[ vg_argi ];
 118
 119    if( carg[0] == '-' )
 120    {
 121       if( carg[1] == '-' )
 122       {
 123          if( !strcmp( name, carg+2 ) )
 124          {
 125             vg_consume_next = 1;
 126             return 1;
 127          }
 128       }
 129    }
 130
 131    return 0;
 132 }
 133
 134 /* Example: get --big=value */
 135 char *vg_long_opt_arg( char *name )
 136 {
 137    char *carg = vg_argv[ vg_argi ];
 138
 139    if( carg[0] == '-' )
 140    {
 141       if( carg[1] == '-' )
 142       {
 143          int k = 2; int set = 0;
 144          while( carg[ k ] )
 145          {
 146             if( carg[ k ] == '=' )
 147             {
 148                set = 1;
 149                break;
 150             }
 151
 152             k ++;
 153          }
 154
 155          if( !strncmp( name, carg+2, k-2 ) )
 156          {
 157             vg_consume_next = 1;
 158
 159             // the rest
 160             if( set )
 161             {
 162                return carg + k + 1;
 163             }
 164             else
 165             {
 166                vg_error( "Long option '%s' requires argument\n", name );
 167             }
 168          }
 169       }
 170    }
 171
 172    return NULL;
 173 }
 174
 175 /* Example: get regular_thing */
 176 char *vg_arg(void)
 177 {
 178    char *carg = vg_argv[ vg_argi ];
 179
 180    if( carg[0] != '-' )
 181    {
 182       vg_consume_next = 1;
 183       return carg;
 184    }
 185
 186    return NULL;
 187 }