ref: c2fb9dc5673b63e8f7286b9d0edbcd8a7865c8bd
dir: /src/deh_str.c/
// Emacs style mode select -*- C++ -*- //----------------------------------------------------------------------------- // // 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. // //----------------------------------------------------------------------------- // // Parses Text substitution sections in dehacked files // //----------------------------------------------------------------------------- #include <stdlib.h> #include <string.h> #include "doomtype.h" #include "deh_str.h" #include "z_zone.h" typedef struct { char *from_text; char *to_text; } deh_substitution_t; static deh_substitution_t **hash_table = NULL; 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 InitHashTable(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_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; } void DEH_AddStringReplacement(char *from_text, char *to_text) { deh_substitution_t *sub; // Initialise the hash table if this is the first time if (hash_table_length < 0) { InitHashTable(); } sub = Z_Malloc(sizeof(*sub), PU_STATIC, 0); sub->from_text = from_text; sub->to_text = to_text; DEH_AddToHashtable(sub); }