xref: /openbsd-src/bin/dd/conv.c (revision 898184e3e61f9129feb5978fad5a8c6865f00b92)
1 /*	$OpenBSD: conv.c,v 1.11 2009/10/27 23:59:21 deraadt Exp $	*/
2 /*	$NetBSD: conv.c,v 1.6 1996/02/20 19:29:02 jtc 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/param.h>
38 #include <sys/time.h>
39 
40 #include <err.h>
41 #include <string.h>
42 
43 #include "dd.h"
44 #include "extern.h"
45 
46 /*
47  * def --
48  * Copy input to output.  Input is buffered until reaches obs, and then
49  * output until less than obs remains.  Only a single buffer is used.
50  * Worst case buffer calculation is (ibs + obs - 1).
51  */
52 void
53 def(void)
54 {
55 	size_t cnt;
56 	u_char *inp;
57 	const u_char *t;
58 
59 	if ((t = ctab) != NULL)
60 		for (inp = in.dbp - (cnt = in.dbrcnt); cnt--; ++inp)
61 			*inp = t[*inp];
62 
63 	/* Make the output buffer look right. */
64 	out.dbp = in.dbp;
65 	out.dbcnt = in.dbcnt;
66 
67 	if (in.dbcnt >= out.dbsz) {
68 		/* If the output buffer is full, write it. */
69 		dd_out(0);
70 
71 		/*
72 		 * Ddout copies the leftover output to the beginning of
73 		 * the buffer and resets the output buffer.  Reset the
74 		 * input buffer to match it.
75 	 	 */
76 		in.dbp = out.dbp;
77 		in.dbcnt = out.dbcnt;
78 	}
79 }
80 
81 void
82 def_close(void)
83 {
84 	/* Just update the count, everything is already in the buffer. */
85 	if (in.dbcnt)
86 		out.dbcnt = in.dbcnt;
87 }
88 
89 #ifdef	NO_CONV
90 /* Build a smaller version (i.e. for a miniroot) */
91 /* These can not be called, but just in case...  */
92 static char no_block[] = "unblock and -DNO_CONV?";
93 void block()       { errx(1, "%s", no_block + 2); }
94 void block_close() { errx(1, "%s", no_block + 2); }
95 void unblock()       { errx(1, "%s", no_block); }
96 void unblock_close() { errx(1, "%s", no_block); }
97 #else	/* NO_CONV */
98 
99 /*
100  * Copy variable length newline terminated records with a max size cbsz
101  * bytes to output.  Records less than cbs are padded with spaces.
102  *
103  * max in buffer:  MAX(ibs, cbsz)
104  * max out buffer: obs + cbsz
105  */
106 void
107 block(void)
108 {
109 	static int intrunc;
110 	int ch = -1;
111 	size_t cnt, maxlen;
112 	u_char *inp, *outp;
113 	const u_char *t;
114 
115 	/*
116 	 * Record truncation can cross block boundaries.  If currently in a
117 	 * truncation state, keep tossing characters until reach a newline.
118 	 * Start at the beginning of the buffer, as the input buffer is always
119 	 * left empty.
120 	 */
121 	if (intrunc) {
122 		for (inp = in.db, cnt = in.dbrcnt;
123 		    cnt && *inp++ != '\n'; --cnt);
124 		if (!cnt) {
125 			in.dbcnt = 0;
126 			in.dbp = in.db;
127 			return;
128 		}
129 		intrunc = 0;
130 		/* Adjust the input buffer numbers. */
131 		in.dbcnt = cnt - 1;
132 		in.dbp = inp + cnt - 1;
133 	}
134 
135 	/*
136 	 * Copy records (max cbsz size chunks) into the output buffer.  The
137 	 * translation is done as we copy into the output buffer.
138 	 */
139 	for (inp = in.dbp - in.dbcnt, outp = out.dbp; in.dbcnt;) {
140 		maxlen = MIN(cbsz, in.dbcnt);
141 		if ((t = ctab) != NULL)
142 			for (cnt = 0;
143 			    cnt < maxlen && (ch = *inp++) != '\n'; ++cnt)
144 				*outp++ = t[ch];
145 		else
146 			for (cnt = 0;
147 			    cnt < maxlen && (ch = *inp++) != '\n'; ++cnt)
148 				*outp++ = ch;
149 		/*
150 		 * Check for short record without a newline.  Reassemble the
151 		 * input block.
152 		 */
153 		if (ch != '\n' && in.dbcnt < cbsz) {
154 			(void)memmove(in.db, in.dbp - in.dbcnt, in.dbcnt);
155 			break;
156 		}
157 
158 		/* Adjust the input buffer numbers. */
159 		in.dbcnt -= cnt;
160 		if (ch == '\n')
161 			--in.dbcnt;
162 
163 		/* Pad short records with spaces. */
164 		if (cnt < cbsz)
165 			(void)memset(outp, ctab ? ctab[' '] : ' ', cbsz - cnt);
166 		else {
167 			/*
168 			 * If the next character wouldn't have ended the
169 			 * block, it's a truncation.
170 			 */
171 			if (!in.dbcnt || *inp != '\n')
172 				++st.trunc;
173 
174 			/* Toss characters to a newline. */
175 			for (; in.dbcnt && *inp++ != '\n'; --in.dbcnt);
176 			if (!in.dbcnt)
177 				intrunc = 1;
178 			else
179 				--in.dbcnt;
180 		}
181 
182 		/* Adjust output buffer numbers. */
183 		out.dbp += cbsz;
184 		if ((out.dbcnt += cbsz) >= out.dbsz)
185 			dd_out(0);
186 		outp = out.dbp;
187 	}
188 	in.dbp = in.db + in.dbcnt;
189 }
190 
191 void
192 block_close(void)
193 {
194 	/*
195 	 * Copy any remaining data into the output buffer and pad to a record.
196 	 * Don't worry about truncation or translation, the input buffer is
197 	 * always empty when truncating, and no characters have been added for
198 	 * translation.  The bottom line is that anything left in the input
199 	 * buffer is a truncated record.  Anything left in the output buffer
200 	 * just wasn't big enough.
201 	 */
202 	if (in.dbcnt) {
203 		++st.trunc;
204 		(void)memmove(out.dbp, in.dbp - in.dbcnt, in.dbcnt);
205 		(void)memset(out.dbp + in.dbcnt,
206 		    ctab ? ctab[' '] : ' ', cbsz - in.dbcnt);
207 		out.dbcnt += cbsz;
208 	}
209 }
210 
211 /*
212  * Convert fixed length (cbsz) records to variable length.  Deletes any
213  * trailing blanks and appends a newline.
214  *
215  * max in buffer:  MAX(ibs, cbsz) + cbsz
216  * max out buffer: obs + cbsz
217  */
218 void
219 unblock(void)
220 {
221 	size_t cnt;
222 	u_char *inp;
223 	const u_char *t;
224 
225 	/* Translation and case conversion. */
226 	if ((t = ctab) != NULL)
227 		for (cnt = in.dbrcnt, inp = in.dbp - 1; cnt--; inp--)
228 			*inp = t[*inp];
229 	/*
230 	 * Copy records (max cbsz size chunks) into the output buffer.  The
231 	 * translation has to already be done or we might not recognize the
232 	 * spaces.
233 	 */
234 	for (inp = in.db; in.dbcnt >= cbsz; inp += cbsz, in.dbcnt -= cbsz) {
235 		for (t = inp + cbsz - 1; t >= inp && *t == ' '; --t);
236 		if (t >= inp) {
237 			cnt = t - inp + 1;
238 			(void)memmove(out.dbp, inp, cnt);
239 			out.dbp += cnt;
240 			out.dbcnt += cnt;
241 		}
242 		++out.dbcnt;
243 		*out.dbp++ = '\n';
244 		if (out.dbcnt >= out.dbsz)
245 			dd_out(0);
246 	}
247 	if (in.dbcnt)
248 		(void)memmove(in.db, in.dbp - in.dbcnt, in.dbcnt);
249 	in.dbp = in.db + in.dbcnt;
250 }
251 
252 void
253 unblock_close(void)
254 {
255 	size_t cnt;
256 	u_char *t;
257 
258 	if (in.dbcnt) {
259 		warnx("%s: short input record", in.name);
260 		for (t = in.db + in.dbcnt - 1; t >= in.db && *t == ' '; --t);
261 		if (t >= in.db) {
262 			cnt = t - in.db + 1;
263 			(void)memmove(out.dbp, in.db, cnt);
264 			out.dbp += cnt;
265 			out.dbcnt += cnt;
266 		}
267 		++out.dbcnt;
268 		*out.dbp++ = '\n';
269 	}
270 }
271 
272 #endif	/* NO_CONV */
273