ref: 2053768a9251cbd4c731681a3e1e04c800ad21f4
dir: /src/w_checksum.c/
// // Copyright(C) 1993-1996 Id Software, Inc. // Copyright(C) 2005-2014 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. // // DESCRIPTION: // Generate a checksum of the WAD directory. // #include <stdio.h> #include <stdlib.h> #include <string.h> #include "i_system.h" #include "m_misc.h" #include "sha1.h" #include "w_checksum.h" #include "w_wad.h" static wad_file_t **open_wadfiles = NULL; static int num_open_wadfiles = 0; static int GetFileNumber(wad_file_t *handle) { int i; int result; for (i = 0; i < num_open_wadfiles; ++i) { if (open_wadfiles[i] == handle) { return i; } } // Not found in list. This is a new file we haven't seen yet. // Allocate another slot for this file. open_wadfiles = I_Realloc(open_wadfiles, sizeof(wad_file_t *) * (num_open_wadfiles + 1)); open_wadfiles[num_open_wadfiles] = handle; result = num_open_wadfiles; ++num_open_wadfiles; return result; } static void ChecksumAddLump(sha1_context_t *sha1_context, lumpinfo_t *lump) { char buf[9]; M_StringCopy(buf, lump->name, sizeof(buf)); SHA1_UpdateString(sha1_context, buf); SHA1_UpdateInt32(sha1_context, GetFileNumber(lump->wad_file)); SHA1_UpdateInt32(sha1_context, lump->position); SHA1_UpdateInt32(sha1_context, lump->size); } void W_Checksum(sha1_digest_t digest) { sha1_context_t sha1_context; unsigned int i; SHA1_Init(&sha1_context); num_open_wadfiles = 0; // Go through each entry in the WAD directory, adding information // about each entry to the SHA1 hash. for (i = 0; i < numlumps; ++i) { ChecksumAddLump(&sha1_context, lumpinfo[i]); } SHA1_Final(digest, &sha1_context); }