usr.bin/hexdump/display.c

   1 /*-
   2  * SPDX-License-Identifier: BSD-3-Clause
   3  *
   4  * Copyright (c) 1989, 1993
   5  *      The Regents of the University of California.  All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  * 3. Neither the name of the University nor the names of its contributors
  16  *    may be used to endorse or promote products derived from this software
  17  *    without specific prior written permission.
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  29  * SUCH DAMAGE.
  30  */
  31
  32 #ifndef lint
  33 #if 0
  34 static char sccsid[] = "@(#)display.c   8.1 (Berkeley) 6/6/93";
  35 #endif
  36 #endif /* not lint */
  37 #include <sys/cdefs.h>
  38 #include <sys/param.h>
  39 #include <sys/capsicum.h>
  40 #include <sys/conf.h>
  41 #include <sys/ioctl.h>
  42 #include <sys/stat.h>
  43
  44 #include <capsicum_helpers.h>
  45 #include <ctype.h>
  46 #include <err.h>
  47 #include <errno.h>
  48 #include <stdio.h>
  49 #include <stdlib.h>
  50 #include <string.h>
  51 #include <unistd.h>
  52 #include "hexdump.h"
  53
  54 enum _vflag vflag = FIRST;
  55
  56 static off_t address;                   /* address/offset in stream */
  57 static off_t eaddress;                  /* end address */
  58
  59 static void print(PR *, u_char *);
  60 static void noseek(void);
  61
  62 void
  63 display(void)
  64 {
  65         FS *fs;
  66         FU *fu;
  67         PR *pr;
  68         int cnt;
  69         u_char *bp;
  70         off_t saveaddress;
  71         u_char savech, *savebp;
  72
  73         savech = 0;
  74         while ((bp = get()))
  75             for (fs = fshead, savebp = bp, saveaddress = address; fs;
  76                 fs = fs->nextfs, bp = savebp, address = saveaddress)
  77                     for (fu = fs->nextfu; fu; fu = fu->nextfu) {
  78                         if (fu->flags&F_IGNORE)
  79                                 break;
  80                         for (cnt = fu->reps; cnt; --cnt)
  81                             for (pr = fu->nextpr; pr; address += pr->bcnt,
  82                                 bp += pr->bcnt, pr = pr->nextpr) {
  83                                     if (eaddress && address >= eaddress &&
  84                                         !(pr->flags & (F_TEXT|F_BPAD)))
  85                                             bpad(pr);
  86                                     if (cnt == 1 && pr->nospace) {
  87                                         savech = *pr->nospace;
  88                                         *pr->nospace = '\0';
  89                                     }
  90                                     print(pr, bp);
  91                                     if (cnt == 1 && pr->nospace)
  92                                         *pr->nospace = savech;
  93                             }
  94                     }
  95         if (endfu) {
  96                 /*
  97                  * If eaddress not set, error or file size was multiple of
  98                  * blocksize, and no partial block ever found.
  99                  */
 100                 if (!eaddress) {
 101                         if (!address)
 102                                 return;
 103                         eaddress = address;
 104                 }
 105                 for (pr = endfu->nextpr; pr; pr = pr->nextpr)
 106                         switch(pr->flags) {
 107                         case F_ADDRESS:
 108                                 (void)printf(pr->fmt, (quad_t)eaddress);
 109                                 break;
 110                         case F_TEXT:
 111                                 (void)printf("%s", pr->fmt);
 112                                 break;
 113                         }
 114         }
 115 }
 116
 117 static void
 118 print(PR *pr, u_char *bp)
 119 {
 120         long double ldbl;
 121            double f8;
 122             float f4;
 123           int16_t s2;
 124           int32_t s4;
 125           int64_t s8;
 126         u_int16_t u2;
 127         u_int32_t u4;
 128         u_int64_t u8;
 129
 130         switch(pr->flags) {
 131         case F_ADDRESS:
 132                 (void)printf(pr->fmt, (quad_t)address);
 133                 break;
 134         case F_BPAD:
 135                 (void)printf(pr->fmt, "");
 136                 break;
 137         case F_C:
 138                 conv_c(pr, bp, eaddress ? eaddress - address :
 139                     blocksize - address % blocksize);
 140                 break;
 141         case F_CHAR:
 142                 (void)printf(pr->fmt, *bp);
 143                 break;
 144         case F_DBL:
 145                 switch(pr->bcnt) {
 146                 case 4:
 147                         bcopy(bp, &f4, sizeof(f4));
 148                         (void)printf(pr->fmt, f4);
 149                         break;
 150                 case 8:
 151                         bcopy(bp, &f8, sizeof(f8));
 152                         (void)printf(pr->fmt, f8);
 153                         break;
 154                 default:
 155                         if (pr->bcnt == sizeof(long double)) {
 156                                 bcopy(bp, &ldbl, sizeof(ldbl));
 157                                 (void)printf(pr->fmt, ldbl);
 158                         }
 159                         break;
 160                 }
 161                 break;
 162         case F_INT:
 163                 switch(pr->bcnt) {
 164                 case 1:
 165                         (void)printf(pr->fmt, (quad_t)(signed char)*bp);
 166                         break;
 167                 case 2:
 168                         bcopy(bp, &s2, sizeof(s2));
 169                         (void)printf(pr->fmt, (quad_t)s2);
 170                         break;
 171                 case 4:
 172                         bcopy(bp, &s4, sizeof(s4));
 173                         (void)printf(pr->fmt, (quad_t)s4);
 174                         break;
 175                 case 8:
 176                         bcopy(bp, &s8, sizeof(s8));
 177                         (void)printf(pr->fmt, s8);
 178                         break;
 179                 }
 180                 break;
 181         case F_P:
 182                 (void)printf(pr->fmt, isprint(*bp) ? *bp : '.');
 183                 break;
 184         case F_STR:
 185                 (void)printf(pr->fmt, (char *)bp);
 186                 break;
 187         case F_TEXT:
 188                 (void)printf("%s", pr->fmt);
 189                 break;
 190         case F_U:
 191                 conv_u(pr, bp);
 192                 break;
 193         case F_UINT:
 194                 switch(pr->bcnt) {
 195                 case 1:
 196                         (void)printf(pr->fmt, (u_quad_t)*bp);
 197                         break;
 198                 case 2:
 199                         bcopy(bp, &u2, sizeof(u2));
 200                         (void)printf(pr->fmt, (u_quad_t)u2);
 201                         break;
 202                 case 4:
 203                         bcopy(bp, &u4, sizeof(u4));
 204                         (void)printf(pr->fmt, (u_quad_t)u4);
 205                         break;
 206                 case 8:
 207                         bcopy(bp, &u8, sizeof(u8));
 208                         (void)printf(pr->fmt, u8);
 209                         break;
 210                 }
 211                 break;
 212         }
 213 }
 214
 215 void
 216 bpad(PR *pr)
 217 {
 218         static char const *spec = " -0+#";
 219         char *p1, *p2;
 220
 221         /*
 222          * Remove all conversion flags; '-' is the only one valid
 223          * with %s, and it's not useful here.
 224          */
 225         pr->flags = F_BPAD;
 226         pr->cchar[0] = 's';
 227         pr->cchar[1] = '\0';
 228         for (p1 = pr->fmt; *p1 != '%'; ++p1);
 229         for (p2 = ++p1; *p1 && strchr(spec, *p1); ++p1);
 230         while ((*p2++ = *p1++));
 231 }
 232
 233 static char **_argv;
 234
 235 u_char *
 236 get(void)
 237 {
 238         static int ateof = 1;
 239         static u_char *curp, *savp;
 240         int n;
 241         int need, nread;
 242         int valid_save = 0;
 243         u_char *tmpp;
 244
 245         if (!curp) {
 246                 if ((curp = calloc(1, blocksize)) == NULL)
 247                         err(1, NULL);
 248                 if ((savp = calloc(1, blocksize)) == NULL)
 249                         err(1, NULL);
 250         } else {
 251                 tmpp = curp;
 252                 curp = savp;
 253                 savp = tmpp;
 254                 address += blocksize;
 255                 valid_save = 1;
 256         }
 257         for (need = blocksize, nread = 0;;) {
 258                 /*
 259                  * if read the right number of bytes, or at EOF for one file,
 260                  * and no other files are available, zero-pad the rest of the
 261                  * block and set the end flag.
 262                  */
 263                 if (!length || (ateof && !next((char **)NULL))) {
 264                         if (odmode && skip > 0)
 265                                 errx(1, "cannot skip past end of input");
 266                         if (need == blocksize)
 267                                 return((u_char *)NULL);
 268                         /*
 269                          * XXX bcmp() is not quite right in the presence
 270                          * of multibyte characters.
 271                          */
 272                         if (need == 0 && vflag != ALL &&
 273                             valid_save &&
 274                             bcmp(curp, savp, nread) == 0) {
 275                                 if (vflag != DUP) {
 276                                         (void)printf("*\n");
 277                                         (void)fflush(stdout);
 278                                 }
 279                                 return((u_char *)NULL);
 280                         }
 281                         bzero((char *)curp + nread, need);
 282                         eaddress = address + nread;
 283                         return(curp);
 284                 }
 285                 n = fread((char *)curp + nread, sizeof(u_char),
 286                     length == -1 ? need : MIN(length, need), stdin);
 287                 if (!n) {
 288                         if (ferror(stdin))
 289                                 warn("%s", _argv[-1]);
 290                         ateof = 1;
 291                         continue;
 292                 }
 293                 ateof = 0;
 294                 if (length != -1)
 295                         length -= n;
 296                 if (!(need -= n)) {
 297                         /*
 298                          * XXX bcmp() is not quite right in the presence
 299                          * of multibyte characters.
 300                          */
 301                         if (vflag == ALL || vflag == FIRST ||
 302                             valid_save == 0 ||
 303                             bcmp(curp, savp, blocksize) != 0) {
 304                                 if (vflag == DUP || vflag == FIRST)
 305                                         vflag = WAIT;
 306                                 return(curp);
 307                         }
 308                         if (vflag == WAIT) {
 309                                 (void)printf("*\n");
 310                                 (void)fflush(stdout);
 311                         }
 312                         vflag = DUP;
 313                         address += blocksize;
 314                         need = blocksize;
 315                         nread = 0;
 316                 }
 317                 else
 318                         nread += n;
 319         }
 320 }
 321
 322 size_t
 323 peek(u_char *buf, size_t nbytes)
 324 {
 325         size_t n, nread;
 326         int c;
 327
 328         if (length != -1 && nbytes > (unsigned int)length)
 329                 nbytes = length;
 330         nread = 0;
 331         while (nread < nbytes && (c = getchar()) != EOF) {
 332                 *buf++ = c;
 333                 nread++;
 334         }
 335         n = nread;
 336         while (n-- > 0) {
 337                 c = *--buf;
 338                 ungetc(c, stdin);
 339         }
 340         return (nread);
 341 }
 342
 343 int
 344 next(char **argv)
 345 {
 346         static int done;
 347         int statok;
 348
 349         if (argv) {
 350                 _argv = argv;
 351                 return(1);
 352         }
 353         for (;;) {
 354                 if (*_argv) {
 355                         done = 1;
 356                         if (!(freopen(*_argv, "r", stdin))) {
 357                                 warn("%s", *_argv);
 358                                 exitval = 1;
 359                                 ++_argv;
 360                                 continue;
 361                         }
 362                         statok = 1;
 363                 } else {
 364                         if (done++)
 365                                 return(0);
 366                         statok = 0;
 367                 }
 368
 369                 if (caph_limit_stream(fileno(stdin), CAPH_READ) < 0)
 370                         err(1, "unable to restrict %s",
 371                             statok ? *_argv : "stdin");
 372
 373                 /*
 374                  * We've opened our last input file; enter capsicum sandbox.
 375                  */
 376                 if (statok == 0 || *(_argv + 1) == NULL) {
 377                         if (caph_enter() < 0)
 378                                 err(1, "unable to enter capability mode");
 379                 }
 380
 381                 if (skip)
 382                         doskip(statok ? *_argv : "stdin", statok);
 383                 if (*_argv)
 384                         ++_argv;
 385                 if (!skip)
 386                         return(1);
 387         }
 388         /* NOTREACHED */
 389 }
 390
 391 void
 392 doskip(const char *fname, int statok)
 393 {
 394         int type;
 395         struct stat sb;
 396
 397         if (statok) {
 398                 if (fstat(fileno(stdin), &sb))
 399                         err(1, "%s", fname);
 400                 if (S_ISREG(sb.st_mode) && skip > sb.st_size) {
 401                         address += sb.st_size;
 402                         skip -= sb.st_size;
 403                         return;
 404                 }
 405         }
 406         if (!statok || S_ISFIFO(sb.st_mode) || S_ISSOCK(sb.st_mode)) {
 407                 noseek();
 408                 return;
 409         }
 410         if (S_ISCHR(sb.st_mode) || S_ISBLK(sb.st_mode)) {
 411                 if (ioctl(fileno(stdin), FIODTYPE, &type))
 412                         err(1, "%s", fname);
 413                 /*
 414                  * Most tape drives don't support seeking,
 415                  * yet fseek() would succeed.
 416                  */
 417                 if (type & D_TAPE) {
 418                         noseek();
 419                         return;
 420                 }
 421         }
 422         if (fseeko(stdin, skip, SEEK_SET)) {
 423                 noseek();
 424                 return;
 425         }
 426         address += skip;
 427         skip = 0;
 428 }
 429
 430 static void
 431 noseek(void)
 432 {
 433         int count;
 434         for (count = 0; count < skip; ++count)
 435                 if (getchar() == EOF)
 436                         break;
 437         address += count;
 438         skip -= count;
 439 }