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 #ifndef lint
  33 #if 0
  34 static char sccsid[] = "@(#)parse.c     8.1 (Berkeley) 6/6/93";
  35 #endif
  36 #endif /* not lint */
  37 #include <sys/cdefs.h>
  38 __FBSDID("$FreeBSD$");
  39
  40 #include <sys/types.h>
  41
  42 #include <err.h>
  43 #include <fcntl.h>
  44 #include <stdio.h>
  45 #include <stdlib.h>
  46 #include <ctype.h>
  47 #include <string.h>
  48 #include "hexdump.h"
  49
  50 FU *endfu;                                      /* format at end-of-data */
  51
  52 void
  53 addfile(const char *name)
  54 {
  55         unsigned char *p;
  56         FILE *fp;
  57         int ch;
  58         char buf[2048 + 1];
  59
  60         if ((fp = fopen(name, "r")) == NULL)
  61                 err(1, "%s", name);
  62         while (fgets(buf, sizeof(buf), fp)) {
  63                 if (!(p = strchr(buf, '\n'))) {
  64                         warnx("line too long");
  65                         while ((ch = getchar()) != '\n' && ch != EOF);
  66                         continue;
  67                 }
  68                 *p = '\0';
  69                 for (p = buf; *p && isspace(*p); ++p);
  70                 if (!*p || *p == '#')
  71                         continue;
  72                 add(p);
  73         }
  74         (void)fclose(fp);
  75 }
  76
  77 void
  78 add(const char *fmt)
  79 {
  80         unsigned const char *p, *savep;
  81         static FS **nextfs;
  82         FS *tfs;
  83         FU *tfu, **nextfu;
  84
  85         /* start new linked list of format units */
  86         if ((tfs = calloc(1, sizeof(FS))) == NULL)
  87                 err(1, NULL);
  88         if (!fshead)
  89                 fshead = tfs;
  90         else
  91                 *nextfs = tfs;
  92         nextfs = &tfs->nextfs;
  93         nextfu = &tfs->nextfu;
  94
  95         /* take the format string and break it up into format units */
  96         for (p = fmt;;) {
  97                 /* skip leading white space */
  98                 for (; isspace(*p); ++p);
  99                 if (!*p)
 100                         break;
 101
 102                 /* allocate a new format unit and link it in */
 103                 if ((tfu = calloc(1, sizeof(FU))) == NULL)
 104                         err(1, NULL);
 105                 *nextfu = tfu;
 106                 nextfu = &tfu->nextfu;
 107                 tfu->reps = 1;
 108
 109                 /* if leading digit, repetition count */
 110                 if (isdigit(*p)) {
 111                         for (savep = p; isdigit(*p); ++p);
 112                         if (!isspace(*p) && *p != '/')
 113                                 badfmt(fmt);
 114                         /* may overwrite either white space or slash */
 115                         tfu->reps = atoi(savep);
 116                         tfu->flags = F_SETREP;
 117                         /* skip trailing white space */
 118                         for (++p; isspace(*p); ++p);
 119                 }
 120
 121                 /* skip slash and trailing white space */
 122                 if (*p == '/')
 123                         while (isspace(*++p));
 124
 125                 /* byte count */
 126                 if (isdigit(*p)) {
 127                         for (savep = p; isdigit(*p); ++p);
 128                         if (!isspace(*p))
 129                                 badfmt(fmt);
 130                         tfu->bcnt = atoi(savep);
 131                         /* skip trailing white space */
 132                         for (++p; isspace(*p); ++p);
 133                 }
 134
 135                 /* format */
 136                 if (*p != '"')
 137                         badfmt(fmt);
 138                 for (savep = ++p; *p != '"';)
 139                         if (*p++ == 0)
 140                                 badfmt(fmt);
 141                 if (!(tfu->fmt = malloc(p - savep + 1)))
 142                         err(1, NULL);
 143                 (void) strlcpy(tfu->fmt, savep, p - savep + 1);
 144                 escape(tfu->fmt);
 145                 p++;
 146         }
 147 }
 148
 149 static const char *spec = ".#-+ 0123456789";
 150
 151 int
 152 size(FS *fs)
 153 {
 154         FU *fu;
 155         int bcnt, cursize;
 156         unsigned char *fmt;
 157         int prec;
 158
 159         /* figure out the data block size needed for each format unit */
 160         for (cursize = 0, fu = fs->nextfu; fu; fu = fu->nextfu) {
 161                 if (fu->bcnt) {
 162                         cursize += fu->bcnt * fu->reps;
 163                         continue;
 164                 }
 165                 for (bcnt = prec = 0, fmt = fu->fmt; *fmt; ++fmt) {
 166                         if (*fmt != '%')
 167                                 continue;
 168                         /*
 169                          * skip any special chars -- save precision in
 170                          * case it's a %s format.
 171                          */
 172                         while (*++fmt != 0 && strchr(spec + 1, *fmt) != NULL)
 173                                 ;
 174                         if (*fmt == 0)
 175                                 badnoconv();
 176                         if (*fmt == '.' && isdigit(*++fmt)) {
 177                                 prec = atoi(fmt);
 178                                 while (isdigit(*++fmt));
 179                         }
 180                         switch(*fmt) {
 181                         case 'c':
 182                                 bcnt += 1;
 183                                 break;
 184                         case 'd': case 'i': case 'o': case 'u':
 185                         case 'x': case 'X':
 186                                 bcnt += 4;
 187                                 break;
 188                         case 'e': case 'E': case 'f': case 'g': case 'G':
 189                                 bcnt += 8;
 190                                 break;
 191                         case 's':
 192                                 bcnt += prec;
 193                                 break;
 194                         case '_':
 195                                 switch(*++fmt) {
 196                                 case 'c': case 'p': case 'u':
 197                                         bcnt += 1;
 198                                         break;
 199                                 }
 200                         }
 201                 }
 202                 cursize += bcnt * fu->reps;
 203         }
 204         return (cursize);
 205 }
 206
 207 void
 208 rewrite(FS *fs)
 209 {
 210         enum { NOTOKAY, USEBCNT, USEPREC } sokay;
 211         PR *pr, **nextpr;
 212         FU *fu;
 213         unsigned char *p1, *p2, *fmtp;
 214         char savech, cs[3];
 215         int nconv, prec;
 216
 217         prec = 0;
 218
 219         for (fu = fs->nextfu; fu; fu = fu->nextfu) {
 220                 /*
 221                  * Break each format unit into print units; each conversion
 222                  * character gets its own.
 223                  */
 224                 nextpr = &fu->nextpr;
 225                 for (nconv = 0, fmtp = fu->fmt; *fmtp; nextpr = &pr->nextpr) {
 226                         if ((pr = calloc(1, sizeof(PR))) == NULL)
 227                                 err(1, NULL);
 228                         *nextpr = pr;
 229
 230                         /* Skip preceding text and up to the next % sign. */
 231                         for (p1 = fmtp; *p1 && *p1 != '%'; ++p1);
 232
 233                         /* Only text in the string. */
 234                         if (!*p1) {
 235                                 pr->fmt = fmtp;
 236                                 pr->flags = F_TEXT;
 237                                 break;
 238                         }
 239
 240                         /*
 241                          * Get precision for %s -- if have a byte count, don't
 242                          * need it.
 243                          */
 244                         if (fu->bcnt) {
 245                                 sokay = USEBCNT;
 246                                 /* Skip to conversion character. */
 247                                 while (*++p1 != 0 && strchr(spec, *p1) != NULL)
 248                                         ;
 249                                 if (*p1 == 0)
 250                                         badnoconv();
 251                         } else {
 252                                 /* Skip any special chars, field width. */
 253                                 while (*++p1 != 0 && strchr(spec + 1, *p1) != NULL)
 254                                         ;
 255                                 if (*p1 == 0)
 256                                         badnoconv();
 257                                 if (*p1 == '.' && isdigit(*++p1)) {
 258                                         sokay = USEPREC;
 259                                         prec = atoi(p1);
 260                                         while (isdigit(*++p1));
 261                                 } else
 262                                         sokay = NOTOKAY;
 263                         }
 264
 265                         p2 = *p1 ? p1 + 1 : p1; /* Set end pointer -- make sure
 266                                                  * that it's non-NUL/-NULL first
 267                                                  * though. */
 268                         cs[0] = *p1;            /* Set conversion string. */
 269                         cs[1] = '\0';
 270
 271                         /*
 272                          * Figure out the byte count for each conversion;
 273                          * rewrite the format as necessary, set up blank-
 274                          * padding for end of data.
 275                          */
 276                         switch(cs[0]) {
 277                         case 'c':
 278                                 pr->flags = F_CHAR;
 279                                 switch(fu->bcnt) {
 280                                 case 0: case 1:
 281                                         pr->bcnt = 1;
 282                                         break;
 283                                 default:
 284                                         p1[1] = '\0';
 285                                         badcnt(p1);
 286                                 }
 287                                 break;
 288                         case 'd': case 'i':
 289                                 pr->flags = F_INT;
 290                                 goto isint;
 291                         case 'o': case 'u': case 'x': case 'X':
 292                                 pr->flags = F_UINT;
 293 isint:                          cs[2] = '\0';
 294                                 cs[1] = cs[0];
 295                                 cs[0] = 'q';
 296                                 switch(fu->bcnt) {
 297                                 case 0: case 4:
 298                                         pr->bcnt = 4;
 299                                         break;
 300                                 case 1:
 301                                         pr->bcnt = 1;
 302                                         break;
 303                                 case 2:
 304                                         pr->bcnt = 2;
 305                                         break;
 306                                 default:
 307                                         p1[1] = '\0';
 308                                         badcnt(p1);
 309                                 }
 310                                 break;
 311                         case 'e': case 'E': case 'f': case 'g': case 'G':
 312                                 pr->flags = F_DBL;
 313                                 switch(fu->bcnt) {
 314                                 case 0: case 8:
 315                                         pr->bcnt = 8;
 316                                         break;
 317                                 case 4:
 318                                         pr->bcnt = 4;
 319                                         break;
 320                                 default:
 321                                         if (fu->bcnt == sizeof(long double)) {
 322                                                 cs[2] = '\0';
 323                                                 cs[1] = cs[0];
 324                                                 cs[0] = 'L';
 325                                                 pr->bcnt = sizeof(long double);
 326                                         } else {
 327                                                 p1[1] = '\0';
 328                                                 badcnt(p1);
 329                                         }
 330                                 }
 331                                 break;
 332                         case 's':
 333                                 pr->flags = F_STR;
 334                                 switch(sokay) {
 335                                 case NOTOKAY:
 336                                         badsfmt();
 337                                 case USEBCNT:
 338                                         pr->bcnt = fu->bcnt;
 339                                         break;
 340                                 case USEPREC:
 341                                         pr->bcnt = prec;
 342                                         break;
 343                                 }
 344                                 break;
 345                         case '_':
 346                                 ++p2;
 347                                 switch(p1[1]) {
 348                                 case 'A':
 349                                         endfu = fu;
 350                                         fu->flags |= F_IGNORE;
 351                                         /* FALLTHROUGH */
 352                                 case 'a':
 353                                         pr->flags = F_ADDRESS;
 354                                         ++p2;
 355                                         switch(p1[2]) {
 356                                         case 'd': case 'o': case'x':
 357                                                 cs[0] = 'q';
 358                                                 cs[1] = p1[2];
 359                                                 cs[2] = '\0';
 360                                                 break;
 361                                         default:
 362                                                 p1[3] = '\0';
 363                                                 badconv(p1);
 364                                         }
 365                                         break;
 366                                 case 'c':
 367                                         pr->flags = F_C;
 368                                         /* cs[0] = 'c'; set in conv_c */
 369                                         goto isint2;
 370                                 case 'p':
 371                                         pr->flags = F_P;
 372                                         cs[0] = 'c';
 373                                         goto isint2;
 374                                 case 'u':
 375                                         pr->flags = F_U;
 376                                         /* cs[0] = 'c'; set in conv_u */
 377 isint2:                                 switch(fu->bcnt) {
 378                                         case 0: case 1:
 379                                                 pr->bcnt = 1;
 380                                                 break;
 381                                         default:
 382                                                 p1[2] = '\0';
 383                                                 badcnt(p1);
 384                                         }
 385                                         break;
 386                                 default:
 387                                         p1[2] = '\0';
 388                                         badconv(p1);
 389                                 }
 390                                 break;
 391                         default:
 392                                 p1[1] = '\0';
 393                                 badconv(p1);
 394                         }
 395
 396                         /*
 397                          * Copy to PR format string, set conversion character
 398                          * pointer, update original.
 399                          */
 400                         savech = *p2;
 401                         p1[0] = '\0';
 402                         if (asprintf(&pr->fmt, "%s%s", fmtp, cs) == -1)
 403                                 err(1, NULL);
 404                         *p2 = savech;
 405                         pr->cchar = pr->fmt + (p1 - fmtp);
 406                         fmtp = p2;
 407
 408                         /* Only one conversion character if byte count. */
 409                         if (!(pr->flags&F_ADDRESS) && fu->bcnt && nconv++)
 410             errx(1, "byte count with multiple conversion characters");
 411                 }
 412                 /*
 413                  * If format unit byte count not specified, figure it out
 414                  * so can adjust rep count later.
 415                  */
 416                 if (!fu->bcnt)
 417                         for (pr = fu->nextpr; pr; pr = pr->nextpr)
 418                                 fu->bcnt += pr->bcnt;
 419         }
 420         /*
 421          * If the format string interprets any data at all, and it's
 422          * not the same as the blocksize, and its last format unit
 423          * interprets any data at all, and has no iteration count,
 424          * repeat it as necessary.
 425          *
 426          * If, rep count is greater than 1, no trailing whitespace
 427          * gets output from the last iteration of the format unit.
 428          */
 429         for (fu = fs->nextfu; fu; fu = fu->nextfu) {
 430                 if (!fu->nextfu && fs->bcnt < blocksize &&
 431                     !(fu->flags&F_SETREP) && fu->bcnt)
 432                         fu->reps += (blocksize - fs->bcnt) / fu->bcnt;
 433                 if (fu->reps > 1) {
 434                         for (pr = fu->nextpr;; pr = pr->nextpr)
 435                                 if (!pr->nextpr)
 436                                         break;
 437                         for (p1 = pr->fmt, p2 = NULL; *p1; ++p1)
 438                                 p2 = isspace(*p1) ? p1 : NULL;
 439                         if (p2)
 440                                 pr->nospace = p2;
 441                 }
 442         }
 443 #ifdef DEBUG
 444         for (fu = fs->nextfu; fu; fu = fu->nextfu) {
 445                 (void)printf("fmt:");
 446                 for (pr = fu->nextpr; pr; pr = pr->nextpr)
 447                         (void)printf(" {%s}", pr->fmt);
 448                 (void)printf("\n");
 449         }
 450 #endif
 451 }
 452
 453 void
 454 escape(char *p1)
 455 {
 456         char *p2;
 457
 458         /* alphabetic escape sequences have to be done in place */
 459         for (p2 = p1;; p1++, p2++) {
 460                 if (*p1 == '\\') {
 461                         p1++;
 462                         switch(*p1) {
 463                         case '\0':
 464                                 *p2 = '\\';
 465                                 *++p2 = '\0';
 466                                 return;
 467                         case 'a':
 468                              /* *p2 = '\a'; */
 469                                 *p2 = '\007';
 470                                 break;
 471                         case 'b':
 472                                 *p2 = '\b';
 473                                 break;
 474                         case 'f':
 475                                 *p2 = '\f';
 476                                 break;
 477                         case 'n':
 478                                 *p2 = '\n';
 479                                 break;
 480                         case 'r':
 481                                 *p2 = '\r';
 482                                 break;
 483                         case 't':
 484                                 *p2 = '\t';
 485                                 break;
 486                         case 'v':
 487                                 *p2 = '\v';
 488                                 break;
 489                         default:
 490                                 *p2 = *p1;
 491                                 break;
 492                         }
 493                 } else {
 494                         *p2 = *p1;
 495                         if (*p1 == '\0')
 496                                 return;
 497                 }
 498         }
 499 }
 500
 501 void
 502 badcnt(const char *s)
 503 {
 504         errx(1, "%s: bad byte count", s);
 505 }
 506
 507 void
 508 badsfmt(void)
 509 {
 510         errx(1, "%%s: requires a precision or a byte count");
 511 }
 512
 513 void
 514 badfmt(const char *fmt)
 515 {
 516         errx(1, "\"%s\": bad format", fmt);
 517 }
 518
 519 void
 520 badconv(const char *ch)
 521 {
 522         errx(1, "%%%s: bad conversion character", ch);
 523 }
 524
 525 void
 526 badnoconv(void)
 527 {
 528         errx(1, "missing conversion character");
 529 }