mdw@git.distorted.org.uk Git - ssr/blob - StraySrc/Libraries/Steel/c/prefs

   1 /*
   2  * prefs
   3  *
   4  * Preferences loading and saving
   5  *
   6  * © 1993-1998 Straylight
   7  */
   8
   9 /*----- Licensing note ----------------------------------------------------*
  10  *
  11  * This file is part of Straylight's Steel library.
  12  *
  13  * Steel is free software; you can redistribute it and/or modify
  14  * it under the terms of the GNU General Public License as published by
  15  * the Free Software Foundation; either version 2, or (at your option)
  16  * any later version.
  17  *
  18  * Steel is distributed in the hope that it will be useful,
  19  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  20  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  21  * GNU General Public License for more details.
  22  *
  23  * You should have received a copy of the GNU General Public License
  24  * along with Steel.  If not, write to the Free Software Foundation,
  25  * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  26  */
  27
  28 #include "prefs.h"
  29 #include "os.h"
  30 #include "utils.h"
  31 #include "msgs.h"
  32 #include "choices.h"
  33 #include "res.h"
  34 #include "kernel.h"
  35 #include "werr.h"
  36
  37 #include <stdio.h>
  38 #include <string.h>
  39 #include <ctype.h>
  40
  41 #define unused(x) ((x)=(x))
  42
  43 static prefs_prefstr *prefs__prefs;
  44
  45 /*
  46  * char *prefs__match(char *a,char *b)
  47  *
  48  * Use
  49  *  Checks to see if the first part of a matches b.  If it does, it returns
  50  *  the rest of a.
  51  *
  52  * Parameters
  53  *  char *a == an input string
  54  *  char *b == a keyword
  55  *
  56  * Returns
  57  *  The part of a following b, or NULL if no match
  58  */
  59
  60 static char *prefs__match(char *a,char *b)
  61 {
  62   if (!*a)
  63     return (0);
  64   while (*b)
  65   {
  66     if (tolower(*(a++))!=tolower(*(b++)))
  67       return (0);
  68   }
  69   while (*a==' ')
  70     a++;
  71   if (*a=='=')
  72     a++;
  73   while (*a==' ')
  74     a++;
  75   return (a);
  76 }
  77
  78 /*
  79  * char *prefs_readBoolean(char *tag,char *args,void *handle)
  80  *
  81  * Use
  82  *  Reads a Boolean variable (i.e. one that can be either TRUE or FALSE).
  83  */
  84
  85 char *prefs_readBoolean(char *tag,char *args,void *handle)
  86 {
  87   unused(tag);
  88   if (utils_caselessCmp(args,"true")==0)
  89     *(BOOL *)handle=TRUE;
  90   else if (utils_caselessCmp(args,"false")==0)
  91     *(BOOL *)handle=FALSE;
  92   else
  93     return (msgs_lookup("prefsRBB:Bad boolean variable '%s' at line %i (must be 'true' or 'false')"));
  94   return (0);
  95 }
  96
  97 /*
  98  * char *prefs_writeBoolean(char *tag,FILE *fp,void *handle)
  99  *
 100  * Use
 101  *  Writes a Boolean variable to the preferences file.
 102  */
 103
 104 char *prefs_writeBoolean(char *tag,FILE *fp,void *handle)
 105 {
 106   fprintf(fp,"%s=%s\n",tag,*(BOOL *)handle ? "true" : "false");
 107   return (0);
 108 }
 109
 110 /*
 111  * char *prefs_readNumeric(char *tag,char *args,void *handle)
 112  *
 113  * Use
 114  *  Reads a signed integer from the preferences file.
 115  */
 116
 117 char *prefs_readNumeric(char *tag,char *args,void *handle)
 118 {
 119   unused(tag);
 120   sscanf(args,"%d",(int *)handle);
 121   return (0);
 122 }
 123
 124 /*
 125  * char *prefs_writeNumeric(char *tag,FILE *fp,void *handle)
 126  *
 127  * Use
 128  *  Writes a signed integer to the preferences file.
 129  */
 130
 131 char *prefs_writeNumeric(char *tag,FILE *fp,void *handle)
 132 {
 133   fprintf(fp,"%s=%i\n",tag,*(int *)handle);
 134   return (0);
 135 }
 136
 137 /*
 138  * char *prefs_readString(char *tag,char *args,void *handle)
 139  *
 140  * Use
 141  *  Reads a string from the preferences file.  It is assumed that the buffer
 142  *  pointed to by handle is big enough.
 143  */
 144
 145 char *prefs_readString(char *tag,char *args,void *handle)
 146 {
 147   char *p;
 148   unused(tag);
 149   if (*args=='\'')
 150   {
 151     for (p=++args;*p && *p!='\'';p++)
 152       /* blank! */;
 153     *p=0;
 154   }
 155   strcpy((char *)handle,args);
 156   return (0);
 157 }
 158
 159 /*
 160  * char *prefs_writeString(char *tag,FILE *fp,void *handle)
 161  *
 162  * Use
 163  *  Writes a signed integer to the preferences file.
 164  */
 165
 166 char *prefs_writeString(char *tag,FILE *fp,void *handle)
 167 {
 168   fprintf(fp,"%s='%s'\n",tag,(char *)handle);
 169   return (0);
 170 }
 171
 172 /*
 173  * void prefs_preferences(prefs_prefstr *p)
 174  *
 175  * Use
 176  *  Sets up the prefs system to use the preferences definition specified.
 177  *  'p' should be a pointer to an array of prefs_prefstrs, terminated by an
 178  *  entry with a null 'tag'.  The preferences file created will be called
 179  *  'Choices' in the current application's directory (<App$Dir>.Choices).
 180  *
 181  * Parameters
 182  *  prefs_prefstr *p == pointer to an array of preferences definitions
 183  */
 184
 185 void prefs_preferences(prefs_prefstr *p)
 186 {
 187   prefs__prefs=p;
 188 }
 189
 190 /*
 191  * void prefs_read(void)
 192  *
 193  * Use
 194  *  Reads preferences from the preferences file.
 195  */
 196
 197 void prefs_read(void)
 198 {
 199   FILE *fp;
 200   int i;
 201   int line=0;
 202   char buff[256];
 203   char *p;
 204   char *args;
 205   char *error;
 206   char *preffile=choices_name("Choices",FALSE);
 207
 208   /* --- Make sure the Preferences file exists --- *
 209    *
 210    * If we can't find the Preferences, we leave the user's buffer unchanged
 211    * to allow defaults
 212    */
 213
 214   if (!res_fileExists(preffile))
 215     return;
 216
 217   /* --- Open the Preferences file --- */
 218
 219   fp=fopen(preffile,"r");
 220   if (!fp)
 221   {
 222     werr(FALSE,
 223          msgs_lookup("prefsERP:Error reading preferences.  "
 224                      "Assuming default preferences."));
 225     return;
 226   }
 227
 228   /* --- Read the file a line at a time and parse it --- */
 229
 230   while (fgets(buff,256,fp))
 231   {
 232     /* --- Bump line count for error messages --- */
 233
 234     line++;
 235
 236     /* --- Strip leading spaces --- */
 237
 238     for (p=buff;isspace(*p);p++)
 239       /* blank! */;
 240
 241     /* --- fgets leaves a return on the end -- kill it --- */
 242
 243     utils_ctermToNterm(p);
 244
 245     /* --- Do something about the line --- */
 246
 247     switch (*p)
 248     {
 249       /* --- Discard blank lines and comments --- */
 250       case 0:
 251       case ';':
 252         break;
 253
 254       /* --- Otherwise find the parser for this variable and call it --- */
 255
 256       default:
 257         for (i=0;prefs__prefs[i].tag;i++)
 258         {
 259           if (args=prefs__match(p,prefs__prefs[i].tag),args)
 260           {
 261             if (prefs__prefs[i].read)
 262             {
 263               if (error=prefs__prefs[i].read(prefs__prefs[i].tag,
 264                                              args,
 265                                              prefs__prefs[i].handle),error)
 266               {
 267                 werr(FALSE,error,prefs__prefs[i].tag,line);
 268                 fclose(fp);
 269                 return;
 270               }
 271             }
 272             break;
 273           }
 274         }
 275         break;
 276     }
 277   }
 278   fclose(fp);
 279 }
 280
 281 /*
 282  * void prefs_write(void)
 283  *
 284  * Use
 285  *  Writes preferences out to disk.
 286  */
 287
 288 void prefs_write(void)
 289 {
 290   int i;
 291   FILE *fp=fopen(choices_name("Choices",TRUE),"w");
 292   char *error;
 293
 294   /* --- Complain if we can't write the file --- */
 295
 296   if (!fp)
 297   {
 298     werr(FALSE,
 299          msgs_lookup("prefsEWP:Error writing preferences: '%s'"),
 300          _kernel_last_oserror()->errmess);
 301     return;
 302   }
 303
 304   /* --- Go through the entries one by one calling the output fns --- */
 305
 306   for (i=0;prefs__prefs[i].tag;i++)
 307   {
 308     if (prefs__prefs[i].tag[0]==';' || prefs__prefs[i].tag[0]=='\n')
 309       fprintf(fp,"%s",prefs__prefs[i].tag);
 310     else if (!prefs__prefs[i].write)
 311       /* blank! */;
 312     else if (error=prefs__prefs[i].write(prefs__prefs[i].tag,
 313                                          fp,
 314                                          prefs__prefs[i].handle),error)
 315     {
 316       werr(FALSE,error,prefs__prefs[i].tag);
 317       fclose(fp);
 318       return;
 319     }
 320   }
 321
 322   /* --- Close the file and exit --- */
 323
 324   fclose(fp);
 325   return;
 326 }