sbin/fsck_msdosfs/boot.c

46 	u_char fsinfo[2 * DOSBOOTBLOCKSIZE];
105 		    || read(dosfs, fsinfo, sizeof fsinfo) != sizeof fsinfo) {
106 			perr("could not read fsinfo block");
109 		if (memcmp(fsinfo, "RRaA", 4)
110 		    || memcmp(fsinfo + 0x1e4, "rrAa", 4)
111 		    || fsinfo[0x1fc]
112 		    || fsinfo[0x1fd]
113 		    || fsinfo[0x1fe] != 0x55
114 		    || fsinfo[0x1ff] != 0xaa
115 		    || fsinfo[0x3fc]
116 		    || fsinfo[0x3fd]
117 		    || fsinfo[0x3fe] != 0x55
118 		    || fsinfo[0x3ff] != 0xaa) {
119 			pwarn("Invalid signature in fsinfo block\n");
121 				memcpy(fsinfo, "RRaA", 4);
122 				memcpy(fsinfo + 0x1e4, "rrAa", 4);
123 				fsinfo[0x1fc] = fsinfo[0x1fd] = 0;
124 				fsinfo[0x1fe] = 0x55;
125 				fsinfo[0x1ff] = 0xaa;
126 				fsinfo[0x3fc] = fsinfo[0x3fd] = 0;
127 				fsinfo[0x3fe] = 0x55;
128 				fsinfo[0x3ff] = 0xaa;
132 				    || write(dosfs, fsinfo, sizeof fsinfo)
133 				    != sizeof fsinfo) {
142 			boot->FSFree = fsinfo[0x1e8] + (fsinfo[0x1e9] << 8)
143 				       + (fsinfo[0x1ea] << 16)
144 				       + (fsinfo[0x1eb] << 24);
145 			boot->FSNext = fsinfo[0x1ec] + (fsinfo[0x1ed] << 8)
146 				       + (fsinfo[0x1ee] << 16)
147 				       + (fsinfo[0x1ef] << 24);
240 	u_char fsinfo[2 * DOSBOOTBLOCKSIZE];
244 	    || read(dosfs, fsinfo, sizeof fsinfo) != sizeof fsinfo) {
245 		perr("could not read fsinfo block");
248 	fsinfo[0x1e8] = (u_char)boot->FSFree;
249 	fsinfo[0x1e9] = (u_char)(boot->FSFree >> 8);
250 	fsinfo[0x1ea] = (u_char)(boot->FSFree >> 16);
251 	fsinfo[0x1eb] = (u_char)(boot->FSFree >> 24);
252 	fsinfo[0x1ec] = (u_char)boot->FSNext;
253 	fsinfo[0x1ed] = (u_char)(boot->FSNext >> 8);
254 	fsinfo[0x1ee] = (u_char)(boot->FSNext >> 16);
255 	fsinfo[0x1ef] = (u_char)(boot->FSNext >> 24);
258 	    || write(dosfs, fsinfo, sizeof fsinfo)
259 	    != sizeof fsinfo) {