sbin/fsck_msdosfs/boot.c

51 	u_char fsinfo[2 * DOSBOOTBLOCKSIZE];
204 		    || read(dosfs, fsinfo, sizeof fsinfo) != sizeof fsinfo) {
205 			perr("could not read fsinfo block");
208 		if (memcmp(fsinfo, "RRaA", 4)
209 		    || memcmp(fsinfo + 0x1e4, "rrAa", 4)
210 		    || fsinfo[0x1fc]
211 		    || fsinfo[0x1fd]
212 		    || fsinfo[0x1fe] != 0x55
213 		    || fsinfo[0x1ff] != 0xaa
214 		    || fsinfo[0x3fc]
215 		    || fsinfo[0x3fd]
216 		    || fsinfo[0x3fe] != 0x55
217 		    || fsinfo[0x3ff] != 0xaa) {
218 			pwarn("Invalid signature in fsinfo block\n");
220 				memcpy(fsinfo, "RRaA", 4);
221 				memcpy(fsinfo + 0x1e4, "rrAa", 4);
222 				fsinfo[0x1fc] = fsinfo[0x1fd] = 0;
223 				fsinfo[0x1fe] = 0x55;
224 				fsinfo[0x1ff] = 0xaa;
225 				fsinfo[0x3fc] = fsinfo[0x3fd] = 0;
226 				fsinfo[0x3fe] = 0x55;
227 				fsinfo[0x3ff] = 0xaa;
231 				    || write(dosfs, fsinfo, sizeof fsinfo)
232 				    != sizeof fsinfo) {
241 			boot->FSFree = fsinfo[0x1e8] + (fsinfo[0x1e9] << 8)
242 				       + (fsinfo[0x1ea] << 16)
243 				       + (fsinfo[0x1eb] << 24);
244 			boot->FSNext = fsinfo[0x1ec] + (fsinfo[0x1ed] << 8)
245 				       + (fsinfo[0x1ee] << 16)
246 				       + (fsinfo[0x1ef] << 24);
341 	u_char fsinfo[2 * DOSBOOTBLOCKSIZE];
345 	    || read(dosfs, fsinfo, sizeof fsinfo) != sizeof fsinfo) {
346 		perr("could not read fsinfo block");
349 	fsinfo[0x1e8] = (u_char)boot->FSFree;
350 	fsinfo[0x1e9] = (u_char)(boot->FSFree >> 8);
351 	fsinfo[0x1ea] = (u_char)(boot->FSFree >> 16);
352 	fsinfo[0x1eb] = (u_char)(boot->FSFree >> 24);
353 	fsinfo[0x1ec] = (u_char)boot->FSNext;
354 	fsinfo[0x1ed] = (u_char)(boot->FSNext >> 8);
355 	fsinfo[0x1ee] = (u_char)(boot->FSNext >> 16);
356 	fsinfo[0x1ef] = (u_char)(boot->FSNext >> 24);
359 	    || write(dosfs, fsinfo, sizeof fsinfo)
360 	    != sizeof fsinfo) {