usr.bin/hexdump/parse.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 #include <sys/types.h>
  33
  34 #include <err.h>
  35 #include <fcntl.h>
  36 #include <stdio.h>
  37 #include <stdlib.h>
  38 #include <ctype.h>
  39 #include <string.h>
  40 #include "hexdump.h"
  41
  42 FU *endfu;                                      /* format at end-of-data */
  43
  44 void
  45 addfile(const char *name)
  46 {
  47         unsigned char *p;
  48         FILE *fp;
  49         int ch;
  50         char buf[2048 + 1];
  51
  52         if ((fp = fopen(name, "r")) == NULL)
  53                 err(1, "%s", name);
  54         while (fgets(buf, sizeof(buf), fp)) {
  55                 if (!(p = strchr(buf, '\n'))) {
  56                         warnx("line too long");
  57                         while ((ch = getchar()) != '\n' && ch != EOF);
  58                         continue;
  59                 }
  60                 *p = '\0';
  61                 for (p = buf; *p && isspace(*p); ++p);
  62                 if (!*p || *p == '#')
  63                         continue;
  64                 add(p);
  65         }
  66         (void)fclose(fp);
  67 }
  68
  69 void
  70 add(const char *fmt)
  71 {
  72         unsigned const char *p, *savep;
  73         static FS **nextfs;
  74         FS *tfs;
  75         FU *tfu, **nextfu;
  76
  77         /* start new linked list of format units */
  78         if ((tfs = calloc(1, sizeof(FS))) == NULL)
  79                 err(1, NULL);
  80         if (!fshead)
  81                 fshead = tfs;
  82         else
  83                 *nextfs = tfs;
  84         nextfs = &tfs->nextfs;
  85         nextfu = &tfs->nextfu;
  86
  87         /* take the format string and break it up into format units */
  88         for (p = fmt;;) {
  89                 /* skip leading white space */
  90                 for (; isspace(*p); ++p);
  91                 if (!*p)
  92                         break;
  93
  94                 /* allocate a new format unit and link it in */
  95                 if ((tfu = calloc(1, sizeof(FU))) == NULL)
  96                         err(1, NULL);
  97                 *nextfu = tfu;
  98                 nextfu = &tfu->nextfu;
  99                 tfu->reps = 1;
 100
 101                 /* if leading digit, repetition count */
 102                 if (isdigit(*p)) {
 103                         for (savep = p; isdigit(*p); ++p);
 104                         if (!isspace(*p) && *p != '/')
 105                                 badfmt(fmt);
 106                         /* may overwrite either white space or slash */
 107                         tfu->reps = atoi(savep);
 108                         tfu->flags = F_SETREP;
 109                         /* skip trailing white space */
 110                         for (++p; isspace(*p); ++p);
 111                 }
 112
 113                 /* skip slash and trailing white space */
 114                 if (*p == '/')
 115                         while (isspace(*++p));
 116
 117                 /* byte count */
 118                 if (isdigit(*p)) {
 119                         for (savep = p; isdigit(*p); ++p);
 120                         if (!isspace(*p))
 121                                 badfmt(fmt);
 122                         tfu->bcnt = atoi(savep);
 123                         /* skip trailing white space */
 124                         for (++p; isspace(*p); ++p);
 125                 }
 126
 127                 /* format */
 128                 if (*p != '"')
 129                         badfmt(fmt);
 130                 for (savep = ++p; *p != '"';)
 131                         if (*p++ == 0)
 132                                 badfmt(fmt);
 133                 if (!(tfu->fmt = malloc(p - savep + 1)))
 134                         err(1, NULL);
 135                 (void) strlcpy(tfu->fmt, savep, p - savep + 1);
 136                 escape(tfu->fmt);
 137                 p++;
 138         }
 139 }
 140
 141 static const char *spec = ".#-+ 0123456789";
 142
 143 int
 144 size(FS *fs)
 145 {
 146         FU *fu;
 147         int bcnt, cursize;
 148         unsigned char *fmt;
 149         int prec;
 150
 151         /* figure out the data block size needed for each format unit */
 152         for (cursize = 0, fu = fs->nextfu; fu; fu = fu->nextfu) {
 153                 if (fu->bcnt) {
 154                         cursize += fu->bcnt * fu->reps;
 155                         continue;
 156                 }
 157                 for (bcnt = prec = 0, fmt = fu->fmt; *fmt; ++fmt) {
 158                         if (*fmt != '%')
 159                                 continue;
 160                         /*
 161                          * skip any special chars -- save precision in
 162                          * case it's a %s format.
 163                          */
 164                         while (*++fmt != 0 && strchr(spec + 1, *fmt) != NULL)
 165                                 ;
 166                         if (*fmt == 0)
 167                                 badnoconv();
 168                         if (*fmt == '.' && isdigit(*++fmt)) {
 169                                 prec = atoi(fmt);
 170                                 while (isdigit(*++fmt));
 171                         }
 172                         switch(*fmt) {
 173                         case 'c':
 174                                 bcnt += 1;
 175                                 break;
 176                         case 'd': case 'i': case 'o': case 'u':
 177                         case 'x': case 'X':
 178                                 bcnt += 4;
 179                                 break;
 180                         case 'e': case 'E': case 'f': case 'g': case 'G':
 181                                 bcnt += 8;
 182                                 break;
 183                         case 's':
 184                                 bcnt += prec;
 185                                 break;
 186                         case '_':
 187                                 switch(*++fmt) {
 188                                 case 'c': case 'p': case 'u':
 189                                         bcnt += 1;
 190                                         break;
 191                                 }
 192                         }
 193                 }
 194                 cursize += bcnt * fu->reps;
 195         }
 196         return (cursize);
 197 }
 198
 199 void
 200 rewrite(FS *fs)
 201 {
 202         enum { NOTOKAY, USEBCNT, USEPREC } sokay;
 203         PR *pr, **nextpr;
 204         FU *fu;
 205         unsigned char *p1, *p2, *fmtp;
 206         char savech, cs[3];
 207         int nconv, prec;
 208
 209         prec = 0;
 210
 211         for (fu = fs->nextfu; fu; fu = fu->nextfu) {
 212                 /*
 213                  * Break each format unit into print units; each conversion
 214                  * character gets its own.
 215                  */
 216                 nextpr = &fu->nextpr;
 217                 for (nconv = 0, fmtp = fu->fmt; *fmtp; nextpr = &pr->nextpr) {
 218                         if ((pr = calloc(1, sizeof(PR))) == NULL)
 219                                 err(1, NULL);
 220                         *nextpr = pr;
 221
 222                         /* Skip preceding text and up to the next % sign. */
 223                         for (p1 = fmtp; *p1 && *p1 != '%'; ++p1);
 224
 225                         /* Only text in the string. */
 226                         if (!*p1) {
 227                                 pr->fmt = fmtp;
 228                                 pr->flags = F_TEXT;
 229                                 break;
 230                         }
 231
 232                         /*
 233                          * Get precision for %s -- if have a byte count, don't
 234                          * need it.
 235                          */
 236                         if (fu->bcnt) {
 237                                 sokay = USEBCNT;
 238                                 /* Skip to conversion character. */
 239                                 while (*++p1 != 0 && strchr(spec, *p1) != NULL)
 240                                         ;
 241                                 if (*p1 == 0)
 242                                         badnoconv();
 243                         } else {
 244                                 /* Skip any special chars, field width. */
 245                                 while (*++p1 != 0 && strchr(spec + 1, *p1) != NULL)
 246                                         ;
 247                                 if (*p1 == 0)
 248                                         badnoconv();
 249                                 if (*p1 == '.' && isdigit(*++p1)) {
 250                                         sokay = USEPREC;
 251                                         prec = atoi(p1);
 252                                         while (isdigit(*++p1));
 253                                 } else
 254                                         sokay = NOTOKAY;
 255                         }
 256
 257                         p2 = *p1 ? p1 + 1 : p1; /* Set end pointer -- make sure
 258                                                  * that it's non-NUL/-NULL first
 259                                                  * though. */
 260                         cs[0] = *p1;            /* Set conversion string. */
 261                         cs[1] = '\0';
 262
 263                         /*
 264                          * Figure out the byte count for each conversion;
 265                          * rewrite the format as necessary, set up blank-
 266                          * padding for end of data.
 267                          */
 268                         switch(cs[0]) {
 269                         case 'c':
 270                                 pr->flags = F_CHAR;
 271                                 switch(fu->bcnt) {
 272                                 case 0: case 1:
 273                                         pr->bcnt = 1;
 274                                         break;
 275                                 default:
 276                                         p1[1] = '\0';
 277                                         badcnt(p1);
 278                                 }
 279                                 break;
 280                         case 'd': case 'i':
 281                                 pr->flags = F_INT;
 282                                 goto isint;
 283                         case 'o': case 'u': case 'x': case 'X':
 284                                 pr->flags = F_UINT;
 285 isint:                          cs[2] = '\0';
 286                                 cs[1] = cs[0];
 287                                 cs[0] = 'q';
 288                                 switch(fu->bcnt) {
 289                                 case 0: case 4:
 290                                         pr->bcnt = 4;
 291                                         break;
 292                                 case 1:
 293                                         pr->bcnt = 1;
 294                                         break;
 295                                 case 2:
 296                                         pr->bcnt = 2;
 297                                         break;
 298                                 case 8:
 299                                         pr->bcnt = 8;
 300                                         break;
 301                                 default:
 302                                         p1[1] = '\0';
 303                                         badcnt(p1);
 304                                 }
 305                                 break;
 306                         case 'e': case 'E': case 'f': case 'g': case 'G':
 307                                 pr->flags = F_DBL;
 308                                 switch(fu->bcnt) {
 309                                 case 0: case 8:
 310                                         pr->bcnt = 8;
 311                                         break;
 312                                 case 4:
 313                                         pr->bcnt = 4;
 314                                         break;
 315                                 default:
 316                                         if (fu->bcnt == sizeof(long double)) {
 317                                                 cs[2] = '\0';
 318                                                 cs[1] = cs[0];
 319                                                 cs[0] = 'L';
 320                                                 pr->bcnt = sizeof(long double);
 321                                         } else {
 322                                                 p1[1] = '\0';
 323                                                 badcnt(p1);
 324                                         }
 325                                 }
 326                                 break;
 327                         case 's':
 328                                 pr->flags = F_STR;
 329                                 switch(sokay) {
 330                                 case NOTOKAY:
 331                                         badsfmt();
 332                                 case USEBCNT:
 333                                         pr->bcnt = fu->bcnt;
 334                                         break;
 335                                 case USEPREC:
 336                                         pr->bcnt = prec;
 337                                         break;
 338                                 }
 339                                 break;
 340                         case '_':
 341                                 ++p2;
 342                                 switch(p1[1]) {
 343                                 case 'A':
 344                                         endfu = fu;
 345                                         fu->flags |= F_IGNORE;
 346                                         /* FALLTHROUGH */
 347                                 case 'a':
 348                                         pr->flags = F_ADDRESS;
 349                                         ++p2;
 350                                         switch(p1[2]) {
 351                                         case 'd': case 'o': case'x':
 352                                                 cs[0] = 'q';
 353                                                 cs[1] = p1[2];
 354                                                 cs[2] = '\0';
 355                                                 break;
 356                                         default:
 357                                                 p1[3] = '\0';
 358                                                 badconv(p1);
 359                                         }
 360                                         break;
 361                                 case 'c':
 362                                         pr->flags = F_C;
 363                                         /* cs[0] = 'c'; set in conv_c */
 364                                         goto isint2;
 365                                 case 'p':
 366                                         pr->flags = F_P;
 367                                         cs[0] = 'c';
 368                                         goto isint2;
 369                                 case 'u':
 370                                         pr->flags = F_U;
 371                                         /* cs[0] = 'c'; set in conv_u */
 372 isint2:                                 switch(fu->bcnt) {
 373                                         case 0: case 1:
 374                                                 pr->bcnt = 1;
 375                                                 break;
 376                                         default:
 377                                                 p1[2] = '\0';
 378                                                 badcnt(p1);
 379                                         }
 380                                         break;
 381                                 default:
 382                                         p1[2] = '\0';
 383                                         badconv(p1);
 384                                 }
 385                                 break;
 386                         default:
 387                                 p1[1] = '\0';
 388                                 badconv(p1);
 389                         }
 390
 391                         /*
 392                          * Copy to PR format string, set conversion character
 393                          * pointer, update original.
 394                          */
 395                         savech = *p2;
 396                         p1[0] = '\0';
 397                         if (asprintf(&pr->fmt, "%s%s", fmtp, cs) == -1)
 398                                 err(1, NULL);
 399                         *p2 = savech;
 400                         pr->cchar = pr->fmt + (p1 - fmtp);
 401                         fmtp = p2;
 402
 403                         /* Only one conversion character if byte count. */
 404                         if (!(pr->flags&F_ADDRESS) && fu->bcnt && nconv++)
 405             errx(1, "byte count with multiple conversion characters");
 406                 }
 407                 /*
 408                  * If format unit byte count not specified, figure it out
 409                  * so can adjust rep count later.
 410                  */
 411                 if (!fu->bcnt)
 412                         for (pr = fu->nextpr; pr; pr = pr->nextpr)
 413                                 fu->bcnt += pr->bcnt;
 414         }
 415         /*
 416          * If the format string interprets any data at all, and it's
 417          * not the same as the blocksize, and its last format unit
 418          * interprets any data at all, and has no iteration count,
 419          * repeat it as necessary.
 420          *
 421          * If, rep count is greater than 1, no trailing whitespace
 422          * gets output from the last iteration of the format unit.
 423          */
 424         for (fu = fs->nextfu; fu; fu = fu->nextfu) {
 425                 if (!fu->nextfu && fs->bcnt < blocksize &&
 426                     !(fu->flags&F_SETREP) && fu->bcnt)
 427                         fu->reps += (blocksize - fs->bcnt) / fu->bcnt;
 428                 if (fu->reps > 1) {
 429                         for (pr = fu->nextpr;; pr = pr->nextpr)
 430                                 if (!pr->nextpr)
 431                                         break;
 432                         for (p1 = pr->fmt, p2 = NULL; *p1; ++p1)
 433                                 p2 = isspace(*p1) ? p1 : NULL;
 434                         if (p2)
 435                                 pr->nospace = p2;
 436                 }
 437         }
 438 #ifdef DEBUG
 439         for (fu = fs->nextfu; fu; fu = fu->nextfu) {
 440                 (void)printf("fmt:");
 441                 for (pr = fu->nextpr; pr; pr = pr->nextpr)
 442                         (void)printf(" {%s}", pr->fmt);
 443                 (void)printf("\n");
 444         }
 445 #endif
 446 }
 447
 448 void
 449 escape(char *p1)
 450 {
 451         char *p2;
 452
 453         /* alphabetic escape sequences have to be done in place */
 454         for (p2 = p1;; p1++, p2++) {
 455                 if (*p1 == '\\') {
 456                         p1++;
 457                         switch(*p1) {
 458                         case '\0':
 459                                 *p2 = '\\';
 460                                 *++p2 = '\0';
 461                                 return;
 462                         case 'a':
 463                              /* *p2 = '\a'; */
 464                                 *p2 = '\007';
 465                                 break;
 466                         case 'b':
 467                                 *p2 = '\b';
 468                                 break;
 469                         case 'f':
 470                                 *p2 = '\f';
 471                                 break;
 472                         case 'n':
 473                                 *p2 = '\n';
 474                                 break;
 475                         case 'r':
 476                                 *p2 = '\r';
 477                                 break;
 478                         case 't':
 479                                 *p2 = '\t';
 480                                 break;
 481                         case 'v':
 482                                 *p2 = '\v';
 483                                 break;
 484                         default:
 485                                 *p2 = *p1;
 486                                 break;
 487                         }
 488                 } else {
 489                         *p2 = *p1;
 490                         if (*p1 == '\0')
 491                                 return;
 492                 }
 493         }
 494 }
 495
 496 void
 497 badcnt(const char *s)
 498 {
 499         errx(1, "%s: bad byte count", s);
 500 }
 501
 502 void
 503 badsfmt(void)
 504 {
 505         errx(1, "%%s: requires a precision or a byte count");
 506 }
 507
 508 void
 509 badfmt(const char *fmt)
 510 {
 511         errx(1, "\"%s\": bad format", fmt);
 512 }
 513
 514 void
 515 badconv(const char *ch)
 516 {
 517         errx(1, "%%%s: bad conversion character", ch);
 518 }
 519
 520 void
 521 badnoconv(void)
 522 {
 523         errx(1, "missing conversion character");
 524 }