ref: 8040eba4c0f8a0996eb6487104646a0e5b261ee7
dir: /src/deh_text.c/
// Emacs style mode select -*- C++ -*-
//-----------------------------------------------------------------------------
//
// $Id: deh_text.c 580 2006-08-31 18:12:43Z fraggle $
//
// Copyright(C) 2005 Simon Howard
//
// This program is free software; you can redistribute it and/or
// modify it under the terms of the GNU General Public License
// as published by the Free Software Foundation; either version 2
// of the License, or (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
// 02111-1307, USA.
//
// $Log$
// Revision 1.5 2006/01/22 21:17:56 fraggle
// Catch calls to DEH_String before DEH_Init is called
//
// Revision 1.4 2005/10/08 20:54:16 fraggle
// Proper dehacked error/warning framework. Catch a load more errors.
//
// Revision 1.3 2005/10/03 21:39:39 fraggle
// Dehacked text substitutions
//
// Revision 1.2 2005/10/03 11:08:16 fraggle
// Replace end of section functions with NULLs as they arent currently being
// used for anything.
//
// Revision 1.1 2005/10/02 23:49:01 fraggle
// The beginnings of dehacked support
//
//
//-----------------------------------------------------------------------------
//
// Parses Text substitution sections in dehacked files
//
//-----------------------------------------------------------------------------
#include "doomdef.h"
#include "doomtype.h"
#include "z_zone.h"
#include "deh_defs.h"
#include "deh_io.h"
typedef struct
{
char *from_text;
char *to_text;
} deh_substitution_t;
static deh_substitution_t **hash_table;
static int hash_table_entries;
static int hash_table_length = -1;
// This is the algorithm used by glib
static unsigned int strhash(char *s)
{
char *p = s;
unsigned int h = *p;
if (h)
{
for (p += 1; *p; p++)
h = (h << 5) - h + *p;
}
return h;
}
// Look up a string to see if it has been replaced with something else
// This will be used throughout the program to substitute text
char *DEH_String(char *s)
{
int entry;
// Fallback if we have not initialised the hash table yet
if (hash_table_length < 0)
return s;
entry = strhash(s) % hash_table_length;
while (hash_table[entry] != NULL)
{
if (!strcmp(hash_table[entry]->from_text, s))
{
// substitution found!
return hash_table[entry]->to_text;
}
entry = (entry + 1) % hash_table_length;
}
// no substitution found
return s;
}
static void DEH_AddToHashtable(deh_substitution_t *sub);
static void IncreaseHashtable(void)
{
deh_substitution_t **old_table;
int old_table_length;
int i;
// save the old table
old_table = hash_table;
old_table_length = hash_table_length;
// double the size
hash_table_length *= 2;
hash_table = Z_Malloc(sizeof(deh_substitution_t *) * hash_table_length,
PU_STATIC, NULL);
memset(hash_table, 0, sizeof(deh_substitution_t *) * hash_table_length);
// go through the old table and insert all the old entries
for (i=0; i<old_table_length; ++i)
{
if (old_table[i] != NULL)
{
DEH_AddToHashtable(old_table[i]);
}
}
// free the old table
Z_Free(old_table);
}
static void DEH_AddToHashtable(deh_substitution_t *sub)
{
int entry;
// if the hash table is more than 60% full, increase its size
if ((hash_table_entries * 10) / hash_table_length > 6)
{
IncreaseHashtable();
}
// find where to insert it
entry = strhash(sub->from_text) % hash_table_length;
while (hash_table[entry] != NULL)
{
entry = (entry + 1) % hash_table_length;
}
hash_table[entry] = sub;
++hash_table_entries;
}
// Given a string length, find the maximum length of a
// string that can replace it.
static int TXT_MaxStringLength(int len)
{
// Enough bytes for the string and the NUL terminator
len += 1;
// All strings in doom.exe are on 4-byte boundaries, so we may be able
// to support a slightly longer string.
// Extend up to the next 4-byte boundary
len += (4 - (len % 4)) % 4;
// Less one for the NUL terminator.
return len - 1;
}
static void DEH_TextInit(void)
{
// init hash table
hash_table_entries = 0;
hash_table_length = 16;
hash_table = Z_Malloc(sizeof(deh_substitution_t *) * hash_table_length,
PU_STATIC, NULL);
memset(hash_table, 0, sizeof(deh_substitution_t *) * hash_table_length);
}
static void *DEH_TextStart(deh_context_t *context, char *line)
{
deh_substitution_t *sub;
int fromlen, tolen;
int i;
if (sscanf(line, "Text %i %i", &fromlen, &tolen) != 2)
{
DEH_Warning(context, "Parse error on section start");
return NULL;
}
// Only allow string replacements that are possible in Vanilla Doom.
// Chocolate Doom is unforgiving!
if (tolen > TXT_MaxStringLength(fromlen))
{
DEH_Error(context, "Replacement string is longer than the maximum "
"possible in doom.exe");
return NULL;
}
sub = Z_Malloc(sizeof(deh_substitution_t), PU_STATIC, NULL);
sub->from_text = Z_Malloc(fromlen + 1, PU_STATIC, NULL);
sub->to_text = Z_Malloc(tolen + 1, PU_STATIC, NULL);
// read in the "from" text
for (i=0; i<fromlen; ++i)
{
int c;
c = DEH_GetChar(context);
sub->from_text[i] = c;
}
sub->from_text[fromlen] = '\0';
// read in the "to" text
for (i=0; i<tolen; ++i)
{
int c;
c = DEH_GetChar(context);
sub->to_text[i] = c;
}
sub->to_text[tolen] = '\0';
DEH_AddToHashtable(sub);
return NULL;
}
static void DEH_TextParseLine(deh_context_t *context, char *line, void *tag)
{
// not used
}
deh_section_t deh_section_text =
{
"Text",
DEH_TextInit,
DEH_TextStart,
DEH_TextParseLine,
NULL,
};