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

   1 /*
   2  * msgs.c
   3  *
   4  * Handling of messages files
   5  *
   6  * © 1994-1998 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 <stdio.h>
  29 #include <stdlib.h>
  30 #include <string.h>
  31 #include <ctype.h>
  32
  33 #include "os.h"
  34 #include "mem.h"
  35 #include "werr.h"
  36 #include "res.h"
  37 #include "msgs.h"
  38
  39 /*----- Special types -----------------------------------------------------*/
  40
  41 typedef struct msgs__node
  42 {
  43   struct msgs__node *left;
  44   struct msgs__node *right;
  45   char tag[20];
  46   char *message;
  47 }
  48 msgs__node;
  49
  50 /*----- Variables ---------------------------------------------------------*/
  51
  52 #define msgs__HASHSIZE 64
  53
  54 static msgs__node *msgs__all[msgs__HASHSIZE];
  55
  56 /*----- Main code ---------------------------------------------------------*/
  57
  58 /*
  59  * int msgs__hash(char *p)
  60  *
  61  * Use
  62  *  Hashes the string pointed to by p
  63  */
  64
  65 static int msgs__hash(char *p)
  66 {
  67   unsigned int h=0;
  68   unsigned int seed=0x46bc93d5;
  69   for (;*p && *p!=':';p++)
  70   {
  71     h=(h*(*p)) ^ seed ^ h;
  72     seed=seed*3141592621ul + 271828189;
  73   }
  74   return ((int)h & (msgs__HASHSIZE-1));
  75 }
  76
  77 /*
  78  * void msgs__add(msgs__node *t,msgs__node **p)
  79  *
  80  * Use
  81  *  Adds node t to the tree with *p as its root
  82  */
  83
  84 static void msgs__add(msgs__node *t,msgs__node **p)
  85 {
  86   int s;
  87   if (*p)
  88   {
  89     s=strcmp(t->tag,(*p)->tag);
  90     if (s>0)
  91       msgs__add(t,&(*p)->right);
  92     else if (s<0)
  93       msgs__add(t,&(*p)->left);
  94   }
  95   else
  96     *p=t;
  97 }
  98
  99 /*
 100  * int msgs__cmp(char *a,char *b)
 101  *
 102  * Use
 103  *  Compares a tag-and-default a with a tag b.
 104  */
 105
 106 static int msgs__cmp(char *a,char *b)
 107 {
 108   for (;;)
 109   {
 110     if ((*a==':' || *a==0) && *b==0)
 111       return (0);
 112     else if (*a!=*b)
 113       return (*a-*b);
 114     a++;
 115     b++;
 116   }
 117 }
 118
 119 /*
 120  * msgs__node *msgs__find(char *tag,msgs__node *t)
 121  *
 122  * Use
 123  *  Finds the tag in the tree pointed to by t
 124  */
 125
 126 static msgs__node *msgs__find(char *tag,msgs__node *t)
 127 {
 128   int s;
 129   if (!t)
 130     return (0);
 131   s=msgs__cmp(tag,t->tag);
 132   if (s>0)
 133     return (msgs__find(tag,t->right));
 134   else if (s<0)
 135     return (msgs__find(tag,t->left));
 136   else
 137     return (t);
 138 }
 139
 140 /*
 141  * void msgs__insert(msgs__node *t)
 142  *
 143  * Use
 144  *  Inserts the given messages structure into the overall messages system.
 145  *
 146  * Parameters
 147  *  msgs__node *t == pointer to a filled in messages structure to fit in.
 148  */
 149
 150 static void msgs__insert(msgs__node *t)
 151 {
 152   int i=msgs__hash(t->tag);
 153   t->left=t->right=0;
 154   msgs__add(t,msgs__all+i);
 155 }
 156
 157 /*
 158  * void msgs_readfile(char *name)
 159  *
 160  * Use
 161  *  Loads the messages file given by name into the messages area.
 162  */
 163
 164 void msgs_readfile(char *name)
 165 {
 166   FILE *fp=res_openfile(name,"r");
 167   int c;
 168   enum
 169   {
 170     newline,
 171     comment,
 172     tag,
 173     newalt,
 174     message,
 175     endoffile
 176   }
 177   state=newline;
 178   msgs__node *t[10];
 179   char *p=0;
 180   int len=0;
 181   int i;
 182   int alts=0;
 183   char msg[1024];
 184
 185   if (!fp)
 186     return;
 187
 188   while (state!=endoffile)
 189   {
 190     c=getc(fp);
 191
 192     switch (state)
 193     {
 194       case newline:
 195         if (c==';' || c=='|' || c=='#')
 196           state=comment;
 197         else if (c==EOF)
 198           state=endoffile;
 199         else if (!isspace(c))
 200         {
 201           alts=0;
 202           t[alts]=mem_alloc(sizeof(msgs__node));
 203           if (!t[alts])
 204           {
 205             fclose(fp);
 206             werr(FALSE,
 207                  msgs_lookup("msgsNEM:Not enough memory to read "
 208                                      "messages file '%s'"),
 209                  name);
 210             return;
 211           }
 212           p=t[alts]->tag;
 213           *p++=c;
 214           state=tag;
 215         }
 216         break;
 217
 218       case comment:
 219         if (c=='\n')
 220           state=newline;
 221         else if (c==EOF)
 222           state=endoffile;
 223         break;
 224
 225       case newalt:
 226         if (c==EOF)
 227         {
 228           for (i=0;i<alts;i++)
 229             mem_free(t[i]);
 230           werr(FALSE,
 231                msgs_lookup("msgsEOF:Unexpected end of file in "
 232                                    "messages file '%s'"),
 233                name);
 234           state=endoffile;
 235         }
 236         else
 237         {
 238           t[alts]=mem_alloc(sizeof(msgs__node));
 239           if (!t[alts])
 240           {
 241             fclose(fp);
 242             for (i=0;i<alts;i++)
 243               mem_free(t[i]);
 244             werr(FALSE,
 245                  msgs_lookup("msgsNEM:Not enough memory to read "
 246                                      "messages file '%s'"),
 247                  name);
 248             return;
 249           }
 250           p=t[alts]->tag;
 251           *p++=c;
 252           state=tag;
 253         }
 254         break;
 255
 256       case tag:
 257         if (c=='\n' || c=='/')
 258         {
 259           *p++=0;
 260           alts++;
 261           state=newalt;
 262         }
 263         else if (c==':')
 264         {
 265           *p++=0;
 266           alts++;
 267           len=0;
 268           p=msg;
 269           state=message;
 270         }
 271         else if (c==EOF)
 272         {
 273           for (i=0;i<=alts;i++)
 274             mem_free(t[i]);
 275           werr(FALSE,
 276                msgs_lookup("msgsEOF:Unexpected end of file in "
 277                                    "messages file '%s'"),
 278                name);
 279           state=endoffile;
 280         }
 281         else
 282           *p++=c;
 283         break;
 284
 285       case message:
 286         if (c==EOF || c=='\n')
 287         {
 288           *p=0;
 289           p=mem_alloc(len+1);
 290           if (!p)
 291           {
 292             fclose(fp);
 293             for (i=0;i<alts;i++)
 294               mem_free(t[i]);
 295             werr(FALSE,
 296                  msgs_lookup("msgsNEM:Not enough memory to read "
 297                                      "messages file '%s'"),
 298                  name);
 299             return;
 300           }
 301           strcpy(p,msg);
 302           for (i=0;i<alts;i++)
 303           {
 304             t[i]->message=p;
 305             msgs__insert(t[i]);
 306           }
 307           alts=0;
 308           state=(c==EOF ? endoffile : newline);
 309         }
 310         else
 311         {
 312           *p++=c;
 313           len++;
 314         }
 315         break;
 316     }
 317   }
 318   fclose(fp);
 319 }
 320
 321 /*
 322  * void msgs_init(void)
 323  *
 324  * Use
 325  *  Reads the messages file `Messages' into memory.
 326  */
 327
 328 void msgs_init(void)
 329 {
 330   msgs_readfile("Messages");
 331 }
 332
 333 /*
 334  * char *msgs_lookup(char *tag)
 335  *
 336  * Use
 337  *  Searches the messages for one with a given tag.
 338  */
 339
 340 char *msgs_lookup(char *tag)
 341 {
 342   msgs__node *t=msgs__find(tag,msgs__all[msgs__hash(tag)]);
 343   char *p;
 344   if (t)
 345     return (t->message);
 346   p=tag;
 347   while (*p)
 348   {
 349     if (*p++==':')
 350       return (p);
 351   }
 352   return (tag);
 353 }
 354
 355 /*
 356  * void msgs_delete(void)
 357  *
 358  * Use
 359  *  Removes all messages from memory.
 360  */
 361
 362 static void msgs__delTree(msgs__node *t)
 363 {
 364   if (!t)
 365     return;
 366   msgs__delTree(t->left);
 367   msgs__delTree(t->right);
 368   mem_free(t);
 369   return;
 370 }
 371
 372 void msgs_delete(void)
 373 {
 374   int i;
 375   for (i=0;i<msgs__HASHSIZE;i++)
 376   {
 377     msgs__delTree(msgs__all[i]);
 378     msgs__all[i]=0;
 379   }
 380 }