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GCC Code Coverage Report

Directory:	./		Exec	Total	Coverage
File:	bin/dd/position.c	Lines:	9	45	20.0 %
Date:	2017-11-07	Branches:	5	42	11.9 %


/*	$OpenBSD: position.c,v 1.10 2009/10/27 23:59:21 deraadt Exp $	*/
/*	$NetBSD: position.c,v 1.4 1995/03/21 09:04:12 cgd Exp $	*/

/*-
 * Copyright (c) 1991, 1993, 1994
 *	The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Keith Muller of the University of California, San Diego and Lance
 * Visser of Convex Computer Corporation.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#include <sys/types.h>
#include <sys/stat.h>
#include <sys/ioctl.h>
#include <sys/mtio.h>
#include <sys/time.h>

#include <err.h>
#include <errno.h>
#include <string.h>
#include <unistd.h>

#include "dd.h"
#include "extern.h"

/*
 * Position input/output data streams before starting the copy.  Device type
 * dependent.  Seekable devices use lseek, and the rest position by reading.
 * Seeking past the end of file can cause null blocks to be written to the
 * output.
 */
void
pos_in(void)
{
	size_t bcnt;
	ssize_t nr;
	off_t cnt;
	int warned;

	/* If not a pipe, tape or tty device, try to seek on it. */
	if (!(in.flags & (ISPIPE|ISTAPE)) && !isatty(in.fd)) {
		if (lseek(in.fd, in.offset * in.dbsz, SEEK_CUR) == -1)
			err(1, "%s", in.name);
		return;
	}

	/*
	 * Read the data.  If a pipe, read until satisfy the number of bytes
	 * being skipped.  No differentiation for reading complete and partial
	 * blocks for other devices.
	 */
	for (bcnt = in.dbsz, cnt = in.offset, warned = 0; cnt;) {
		if ((nr = read(in.fd, in.db, bcnt)) > 0) {
			if (in.flags & ISPIPE) {
				if (!(bcnt -= nr)) {
					bcnt = in.dbsz;
					--cnt;
				}
			} else
				--cnt;
			continue;
		}

		if (nr == 0) {
			if (files_cnt > 1) {
				--files_cnt;
				continue;
			}
			errx(1, "skip reached end of input");
		}

		/*
		 * Input error -- either EOF with no more files, or I/O error.
		 * If noerror not set die.  POSIX requires that the warning
		 * message be followed by an I/O display.
		 */
		if (ddflags & C_NOERROR) {
			if (!warned) {
				warn("%s", in.name);
				warned = 1;
				summary();
			}
			continue;
		}
		err(1, "%s", in.name);
	}
}

void
pos_out(void)
{
	struct mtop t_op;
	off_t cnt;
	ssize_t n;

	/*
	 * If not a tape, try seeking on the file.  Seeking on a pipe is
	 * going to fail, but don't protect the user -- they shouldn't
	 * have specified the seek operand.
	 */
	if (!(out.flags & ISTAPE)) {
		if (lseek(out.fd, out.offset * out.dbsz, SEEK_SET) == -1)
			err(1, "%s", out.name);
		return;
	}

	/* If no read access, try using mtio. */
	if (out.flags & NOREAD) {
		t_op.mt_op = MTFSR;
		t_op.mt_count = out.offset;

		if (ioctl(out.fd, MTIOCTOP, &t_op) < 0)
			err(1, "%s", out.name);
		return;
	}

	/* Read it. */
	for (cnt = 0; cnt < out.offset; ++cnt) {
		if ((n = read(out.fd, out.db, out.dbsz)) > 0)
			continue;

		if (n < 0)
			err(1, "%s", out.name);

		/*
		 * If reach EOF, fill with NUL characters; first, back up over
		 * the EOF mark.  Note, cnt has not yet been incremented, so
		 * the EOF read does not count as a seek'd block.
		 */
		t_op.mt_op = MTBSR;
		t_op.mt_count = 1;
		if (ioctl(out.fd, MTIOCTOP, &t_op) == -1)
			err(1, "%s", out.name);

		while (cnt++ < out.offset)
			if ((n = write(out.fd, out.db, out.dbsz)) != out.dbsz)
				err(1, "%s", out.name);
		break;
	}
}


Generated by: GCOVR (Version 3.3)

Line	Branch	Exec	Source
1			/* $OpenBSD: position.c,v 1.10 2009/10/27 23:59:21 deraadt Exp $ */
2			/* $NetBSD: position.c,v 1.4 1995/03/21 09:04:12 cgd Exp $ */
3
4			/*-
5			* Copyright (c) 1991, 1993, 1994
6			* The Regents of the University of California. All rights reserved.
7			*
8			* This code is derived from software contributed to Berkeley by
9			* Keith Muller of the University of California, San Diego and Lance
10			* Visser of Convex Computer Corporation.
11			*
12			* Redistribution and use in source and binary forms, with or without
13			* modification, are permitted provided that the following conditions
14			* are met:
15			* 1. Redistributions of source code must retain the above copyright
16			* notice, this list of conditions and the following disclaimer.
17			* 2. Redistributions in binary form must reproduce the above copyright
18			* notice, this list of conditions and the following disclaimer in the
19			* documentation and/or other materials provided with the distribution.
20			* 3. Neither the name of the University nor the names of its contributors
21			* may be used to endorse or promote products derived from this software
22			* without specific prior written permission.
23			*
24			* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25			* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26			* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27			* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28			* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29			* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30			* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31			* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32			* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33			* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34			* SUCH DAMAGE.
35			*/
36
37			#include <sys/types.h>
38			#include <sys/stat.h>
39			#include <sys/ioctl.h>
40			#include <sys/mtio.h>
41			#include <sys/time.h>
42
43			#include <err.h>
44			#include <errno.h>
45			#include <string.h>
46			#include <unistd.h>
47
48			#include "dd.h"
49			#include "extern.h"
50
51			/*
52			* Position input/output data streams before starting the copy. Device type
53			* dependent. Seekable devices use lseek, and the rest position by reading.
54			* Seeking past the end of file can cause null blocks to be written to the
55			* output.
56			*/
57			void
58			pos_in(void)
59			{
60			size_t bcnt;
61			ssize_t nr;
62			off_t cnt;
63			int warned;
64
65			/* If not a pipe, tape or tty device, try to seek on it. */
66	✓✗✓✗	3333	if (!(in.flags & (ISPIPE\|ISTAPE)) && !isatty(in.fd)) {
67	✗✓	1111	if (lseek(in.fd, in.offset * in.dbsz, SEEK_CUR) == -1)
68			err(1, "%s", in.name);
69		1111	return;
70			}
71
72			/*
73			* Read the data. If a pipe, read until satisfy the number of bytes
74			* being skipped. No differentiation for reading complete and partial
75			* blocks for other devices.
76			*/
77			for (bcnt = in.dbsz, cnt = in.offset, warned = 0; cnt;) {
78			if ((nr = read(in.fd, in.db, bcnt)) > 0) {
79			if (in.flags & ISPIPE) {
80			if (!(bcnt -= nr)) {
81			bcnt = in.dbsz;
82			--cnt;
83			}
84			} else
85			--cnt;
86			continue;
87			}
88
89			if (nr == 0) {
90			if (files_cnt > 1) {
91			--files_cnt;
92			continue;
93			}
94			errx(1, "skip reached end of input");
95			}
96
97			/*
98			* Input error -- either EOF with no more files, or I/O error.
99			* If noerror not set die. POSIX requires that the warning
100			* message be followed by an I/O display.
101			*/
102			if (ddflags & C_NOERROR) {
103			if (!warned) {
104			warn("%s", in.name);
105			warned = 1;
106			summary();
107			}
108			continue;
109			}
110			err(1, "%s", in.name);
111			}
112		1111	}
113
114			void
115			pos_out(void)
116			{
117		2262	struct mtop t_op;
118			off_t cnt;
119			ssize_t n;
120
121			/*
122			* If not a tape, try seeking on the file. Seeking on a pipe is
123			* going to fail, but don't protect the user -- they shouldn't
124			* have specified the seek operand.
125			*/
126	✓✗	1131	if (!(out.flags & ISTAPE)) {
127	✗✓	1131	if (lseek(out.fd, out.offset * out.dbsz, SEEK_SET) == -1)
128			err(1, "%s", out.name);
129		1131	return;
130			}
131
132			/* If no read access, try using mtio. */
133			if (out.flags & NOREAD) {
134			t_op.mt_op = MTFSR;
135			t_op.mt_count = out.offset;
136
137			if (ioctl(out.fd, MTIOCTOP, &t_op) < 0)
138			err(1, "%s", out.name);
139			return;
140			}
141
142			/* Read it. */
143			for (cnt = 0; cnt < out.offset; ++cnt) {
144			if ((n = read(out.fd, out.db, out.dbsz)) > 0)
145			continue;
146
147			if (n < 0)
148			err(1, "%s", out.name);
149
150			/*
151			* If reach EOF, fill with NUL characters; first, back up over
152			* the EOF mark. Note, cnt has not yet been incremented, so
153			* the EOF read does not count as a seek'd block.
154			*/
155			t_op.mt_op = MTBSR;
156			t_op.mt_count = 1;
157			if (ioctl(out.fd, MTIOCTOP, &t_op) == -1)
158			err(1, "%s", out.name);
159
160			while (cnt++ < out.offset)
161			if ((n = write(out.fd, out.db, out.dbsz)) != out.dbsz)
162			err(1, "%s", out.name);
163			break;
164			}
165		1131	}