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
75 IO	in, out;		/* input/output state */
129 	if (in.name == NULL) {
130 		in.name = "stdin";
131 		in.fd = STDIN_FILENO;
133 		in.fd = open(in.name, O_RDONLY, 0);
134 		if (in.fd == -1)
135 			err(1, "%s", in.name);
138 	getfdtype(&in);
140 	if (files_cnt > 1 && !(in.flags & ISTAPE))
171 		if ((in.db = malloc(out.dbsz + in.dbsz - 1)) == NULL)
173 		out.db = in.db;
174 	} else if ((in.db = malloc(MAX(in.dbsz, cbsz) + cbsz)) == NULL ||
178 	/* dbp is the first free position in each buffer. */
179 	in.dbp = in.db;
183 	if (in.offset)
303 				memset(in.dbp, fill_char, in.dbsz);
305 				memset(in.dbp, ' ', in.dbsz);
307 				memset(in.dbp, 0, in.dbsz);
310 		n = read(in.fd, in.dbp, in.dbsz);
312 			in.dbrcnt = 0;
323 				err(1, "%s", in.name);
324 			warn("%s", in.name);
331 			 * in sector size chunks.
333 			if (in.flags & ISSEEK &&
334 			    lseek(in.fd, (off_t)in.dbsz, SEEK_CUR))
335 				warn("%s", in.name);
342 			in.dbcnt += in.dbrcnt = in.dbsz;
346 		} else if ((size_t)n == in.dbsz) {
347 			in.dbcnt += in.dbrcnt = n;
354 				in.dbcnt += in.dbrcnt = in.dbsz;
356 				in.dbcnt += in.dbrcnt = n;
366 			out.dbcnt = in.dbcnt;
368 			in.dbcnt = 0;
373 			if ((n = in.dbrcnt) & 1) {
377 			swab(in.dbp, in.dbp, (size_t)n);
380 		in.dbp += in.dbrcnt;
434 	 * output block in a single write; increment the full block stats.
441 	 * write the block in multiple chunks.  The original versions of dd(1)
442 	 * never wrote a block in more than a single write, so the latter case
445 	 * One special case is if we're forced to do the write -- in that case
475 					 * to write, in which case we'll need to call