bin/dd/dd.c

9  * Redistribution and use in source and binary forms, with or without
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
74 IO	in, out;		/* input/output state */
128 	if (in.name == NULL) {
129 		in.name = "stdin";
130 		in.fd = STDIN_FILENO;
132 		in.fd = open(in.name, O_RDONLY, 0);
133 		if (in.fd == -1)
134 			err(1, "%s", in.name);
137 	getfdtype(&in);
139 	if (files_cnt > 1 && !(in.flags & ISTAPE))
170 		if ((in.db = malloc(out.dbsz + in.dbsz - 1)) == NULL)
172 		out.db = in.db;
173 	} else if ((in.db = malloc(MAX(in.dbsz, cbsz) + cbsz)) == NULL ||
176 	in.dbp = in.db;
180 	if (in.offset)
300 				memset(in.dbp, fill_char, in.dbsz);
302 				memset(in.dbp, ' ', in.dbsz);
304 				memset(in.dbp, 0, in.dbsz);
307 		n = read(in.fd, in.dbp, in.dbsz);
309 			in.dbrcnt = 0;
320 				err(1, "%s", in.name);
321 			warn("%s", in.name);
328 			 * in sector size chunks.
330 			if (in.flags & ISSEEK &&
331 			    lseek(in.fd, (off_t)in.dbsz, SEEK_CUR))
332 				warn("%s", in.name);
339 			in.dbcnt += in.dbrcnt = in.dbsz;
343 		} else if ((size_t)n == in.dbsz) {
344 			in.dbcnt += in.dbrcnt = n;
351 				in.dbcnt += in.dbrcnt = in.dbsz;
353 				in.dbcnt += in.dbrcnt = n;
363 			out.dbcnt = in.dbcnt;
365 			in.dbcnt = 0;
370 			if ((n = in.dbrcnt) & 1) {
374 			swab(in.dbp, in.dbp, (size_t)n);
377 		in.dbp += in.dbrcnt;
422 	 * output block in a single write; increment the full block stats.
429 	 * write the block in multiple chunks.  The original versions of dd(1)
430 	 * never wrote a block in more than a single write, so the latter case
433 	 * One special case is if we're forced to do the write -- in that case