bin/dd/conv.c

   1 /*-
   2  * SPDX-License-Identifier: BSD-3-Clause
   3  *
   4  * Copyright (c) 1991, 1993, 1994
   5  *      The Regents of the University of California.  All rights reserved.
   6  *
   7  * This code is derived from software contributed to Berkeley by
   8  * Keith Muller of the University of California, San Diego and Lance
   9  * Visser of Convex Computer Corporation.
  10  *
  11  * Redistribution and use in source and binary forms, with or without
  12  * modification, are permitted provided that the following conditions
  13  * are met:
  14  * 1. Redistributions of source code must retain the above copyright
  15  *    notice, this list of conditions and the following disclaimer.
  16  * 2. Redistributions in binary form must reproduce the above copyright
  17  *    notice, this list of conditions and the following disclaimer in the
  18  *    documentation and/or other materials provided with the distribution.
  19  * 3. Neither the name of the University nor the names of its contributors
  20  *    may be used to endorse or promote products derived from this software
  21  *    without specific prior written permission.
  22  *
  23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  33  * SUCH DAMAGE.
  34  *
  35  * @(#)conv.c   8.3 (Berkeley) 4/2/94
  36  * $FreeBSD: head/bin/dd/conv.c 326025 2017-11-20 19:49:47Z pfg $
  37  */
  38
  39 #include <sys/param.h>
  40
  41 #include <err.h>
  42 #include <string.h>
  43
  44 #include "dd.h"
  45 #include "extern.h"
  46
  47 /*
  48  * def --
  49  * Copy input to output.  Input is buffered until reaches obs, and then
  50  * output until less than obs remains.  Only a single buffer is used.
  51  * Worst case buffer calculation is (ibs + obs - 1).
  52  */
  53 void
  54 def(void)
  55 {
  56         u_char *inp;
  57         const u_char *t;
  58         size_t cnt;
  59
  60         if ((t = ctab) != NULL)
  61                 for (inp = in.dbp - (cnt = in.dbrcnt); cnt--; ++inp)
  62                         *inp = t[*inp];
  63
  64         /* Make the output buffer look right. */
  65         out.dbp = in.dbp;
  66         out.dbcnt = in.dbcnt;
  67
  68         if (in.dbcnt >= out.dbsz) {
  69                 /* If the output buffer is full, write it. */
  70                 dd_out(0);
  71
  72                 /*
  73                  * dd_out copies the leftover output to the beginning of
  74                  * the buffer and resets the output buffer.  Reset the
  75                  * input buffer to match it.
  76                  */
  77                 in.dbp = out.dbp;
  78                 in.dbcnt = out.dbcnt;
  79         }
  80 }
  81
  82 void
  83 def_close(void)
  84 {
  85         /* Just update the count, everything is already in the buffer. */
  86         if (in.dbcnt)
  87                 out.dbcnt = in.dbcnt;
  88 }
  89
  90 /*
  91  * Copy variable length newline terminated records with a max size cbsz
  92  * bytes to output.  Records less than cbs are padded with spaces.
  93  *
  94  * max in buffer:  MAX(ibs, cbsz)
  95  * max out buffer: obs + cbsz
  96  */
  97 void
  98 block(void)
  99 {
 100         u_char *inp, *outp;
 101         const u_char *t;
 102         size_t cnt, maxlen;
 103         static int intrunc;
 104         int ch;
 105
 106         /*
 107          * Record truncation can cross block boundaries.  If currently in a
 108          * truncation state, keep tossing characters until reach a newline.
 109          * Start at the beginning of the buffer, as the input buffer is always
 110          * left empty.
 111          */
 112         if (intrunc) {
 113                 for (inp = in.db, cnt = in.dbrcnt; cnt && *inp++ != '\n'; --cnt)
 114                         ;
 115                 if (!cnt) {
 116                         in.dbcnt = 0;
 117                         in.dbp = in.db;
 118                         return;
 119                 }
 120                 intrunc = 0;
 121                 /* Adjust the input buffer numbers. */
 122                 in.dbcnt = cnt - 1;
 123                 in.dbp = inp + cnt - 1;
 124         }
 125
 126         /*
 127          * Copy records (max cbsz size chunks) into the output buffer.  The
 128          * translation is done as we copy into the output buffer.
 129          */
 130         ch = 0;
 131         for (inp = in.dbp - in.dbcnt, outp = out.dbp; in.dbcnt;) {
 132                 maxlen = MIN(cbsz, (size_t)in.dbcnt);
 133                 if ((t = ctab) != NULL) {
 134                         for (cnt = 0; cnt < maxlen && (ch = *inp++) != '\n';
 135                             ++cnt)
 136                                 *outp++ = t[ch];
 137                 } else {
 138                         for (cnt = 0; cnt < maxlen && (ch = *inp++) != '\n';
 139                             ++cnt)
 140                                 *outp++ = ch;
 141                 }
 142                 /*
 143                  * Check for short record without a newline.  Reassemble the
 144                  * input block.
 145                  */
 146                 if (ch != '\n' && (size_t)in.dbcnt < cbsz) {
 147                         memmove(in.db, in.dbp - in.dbcnt, in.dbcnt);
 148                         break;
 149                 }
 150
 151                 /* Adjust the input buffer numbers. */
 152                 in.dbcnt -= cnt;
 153                 if (ch == '\n')
 154                         --in.dbcnt;
 155
 156                 /* Pad short records with spaces. */
 157                 if (cnt < cbsz) {
 158                         memset(outp, ctab ? ctab[' '] : ' ', cbsz - cnt);
 159                 } else {
 160                         /*
 161                          * If the next character wouldn't have ended the
 162                          * block, it's a truncation.
 163                          */
 164                         if (!in.dbcnt || *inp != '\n')
 165                                 ++st.trunc;
 166
 167                         /* Toss characters to a newline. */
 168                         for (; in.dbcnt && *inp++ != '\n'; --in.dbcnt)
 169                                 ;
 170                         if (!in.dbcnt)
 171                                 intrunc = 1;
 172                         else
 173                                 --in.dbcnt;
 174                 }
 175
 176                 /* Adjust output buffer numbers. */
 177                 out.dbp += cbsz;
 178                 if ((out.dbcnt += cbsz) >= out.dbsz)
 179                         dd_out(0);
 180                 outp = out.dbp;
 181         }
 182         in.dbp = in.db + in.dbcnt;
 183 }
 184
 185 void
 186 block_close(void)
 187 {
 188         /*
 189          * Copy any remaining data into the output buffer and pad to a record.
 190          * Don't worry about truncation or translation, the input buffer is
 191          * always empty when truncating, and no characters have been added for
 192          * translation.  The bottom line is that anything left in the input
 193          * buffer is a truncated record.  Anything left in the output buffer
 194          * just wasn't big enough.
 195          */
 196         if (in.dbcnt) {
 197                 ++st.trunc;
 198                 memmove(out.dbp, in.dbp - in.dbcnt, in.dbcnt);
 199                 memset(out.dbp + in.dbcnt, ctab ? ctab[' '] : ' ',
 200                     cbsz - in.dbcnt);
 201                 out.dbcnt += cbsz;
 202         }
 203 }
 204
 205 /*
 206  * Convert fixed length (cbsz) records to variable length.  Deletes any
 207  * trailing blanks and appends a newline.
 208  *
 209  * max in buffer:  MAX(ibs, cbsz) + cbsz
 210  * max out buffer: obs + cbsz
 211  */
 212 void
 213 unblock(void)
 214 {
 215         u_char *inp;
 216         const u_char *t;
 217         size_t cnt;
 218
 219         /* Translation and case conversion. */
 220         if ((t = ctab) != NULL)
 221                 for (inp = in.dbp - (cnt = in.dbrcnt); cnt--; ++inp)
 222                         *inp = t[*inp];
 223         /*
 224          * Copy records (max cbsz size chunks) into the output buffer.  The
 225          * translation has to already be done or we might not recognize the
 226          * spaces.
 227          */
 228         for (inp = in.db; (size_t)in.dbcnt >= cbsz; inp += cbsz, in.dbcnt -= cbsz) {
 229                 for (t = inp + cbsz - 1; t >= inp && *t == ' '; --t)
 230                         ;
 231                 if (t >= inp) {
 232                         cnt = t - inp + 1;
 233                         memmove(out.dbp, inp, cnt);
 234                         out.dbp += cnt;
 235                         out.dbcnt += cnt;
 236                 }
 237                 *out.dbp++ = '\n';
 238                 if (++out.dbcnt >= out.dbsz)
 239                         dd_out(0);
 240         }
 241         if (in.dbcnt)
 242                 memmove(in.db, in.dbp - in.dbcnt, in.dbcnt);
 243         in.dbp = in.db + in.dbcnt;
 244 }
 245
 246 void
 247 unblock_close(void)
 248 {
 249         u_char *t;
 250         size_t cnt;
 251
 252         if (in.dbcnt) {
 253                 warnx("%s: short input record", in.name);
 254                 for (t = in.db + in.dbcnt - 1; t >= in.db && *t == ' '; --t)
 255                         ;
 256                 if (t >= in.db) {
 257                         cnt = t - in.db + 1;
 258                         memmove(out.dbp, in.db, cnt);
 259                         out.dbp += cnt;
 260                         out.dbcnt += cnt;
 261                 }
 262                 ++out.dbcnt;
 263                 *out.dbp++ = '\n';
 264         }
 265 }