nl.c

   1 /*      $NetBSD: nl.c,v 1.15 2020/12/31 04:07:37 ginsbach Exp $ */
   2
   3 /*-
   4  * Copyright (c) 1999 The NetBSD Foundation, Inc.
   5  * All rights reserved.
   6  *
   7  * This code is derived from software contributed to The NetBSD Foundation
   8  * by Klaus Klein.
   9  *
  10  * Redistribution and use in source and binary forms, with or without
  11  * modification, are permitted provided that the following conditions
  12  * are met:
  13  * 1. Redistributions of source code must retain the above copyright
  14  *    notice, this list of conditions and the following disclaimer.
  15  * 2. Redistributions in binary form must reproduce the above copyright
  16  *    notice, this list of conditions and the following disclaimer in the
  17  *    documentation and/or other materials provided with the distribution.
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
  20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
  21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
  23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  29  * POSSIBILITY OF SUCH DAMAGE.
  30  */
  31
  32 #include <errno.h>
  33 #include <limits.h>
  34 #include <locale.h>
  35 #include <regex.h>
  36 #include <stdio.h>
  37 #include <stdlib.h>
  38 #include <string.h>
  39 #include <unistd.h>
  40
  41 #define errx(code, ...) { dprintf(2, __VA_ARGS__); exit(code); }
  42
  43 typedef enum {
  44         number_all,             /* number all lines */
  45         number_nonempty,        /* number non-empty lines */
  46         number_none,            /* no line numbering */
  47         number_regex            /* number lines matching regular expression */
  48 } numbering_type;
  49
  50 struct numbering_property {
  51         const char * const      name;           /* for diagnostics */
  52         numbering_type          type;           /* numbering type */
  53         regex_t                 expr;           /* for type == number_regex */
  54 };
  55
  56 /* line numbering formats */
  57 #define FORMAT_LN       "%-*d"  /* left justified, leading zeros suppressed */
  58 #define FORMAT_RN       "%*d"   /* right justified, leading zeros suppressed */
  59 #define FORMAT_RZ       "%0*d"  /* right justified, leading zeros kept */
  60
  61 #define FOOTER          0
  62 #define BODY            1
  63 #define HEADER          2
  64 #define NP_LAST         HEADER
  65
  66 static struct numbering_property numbering_properties[NP_LAST + 1] = {
  67         { "footer",     number_none,    { 0, 0, 0, 0 } },
  68         { "body",       number_nonempty, { 0, 0, 0, 0 } },
  69         { "header",     number_none,    { 0, 0, 0, 0 } },
  70 };
  71
  72 #define max(a, b)       ((a) > (b) ? (a) : (b))
  73
  74 /*
  75  * Maximum number of characters required for a decimal representation of a
  76  * (signed) int; courtesy of tzcode.
  77  */
  78 #define INT_STRLEN_MAXIMUM \
  79         ((sizeof (int) * CHAR_BIT - 1) * 302 / 1000 + 2)
  80
  81 static void     filter(void);
  82 static void     parse_numbering(const char *, int);
  83 static void     usage(char *) __attribute__((__noreturn__));
  84
  85 /*
  86  * Pointer to dynamically allocated input line buffer, and its size.
  87  */
  88 static char *buffer;
  89 static size_t buffersize;
  90
  91 /*
  92  * Dynamically allocated buffer suitable for string representation of ints.
  93  */
  94 static char *intbuffer;
  95 static size_t intbuffersize;
  96
  97 /*
  98  * Configurable parameters.
  99  */
 100 /* delimiter characters that indicate the start of a logical page section */
 101 static char delim[2] = { '\\', ':' };
 102
 103 /* line numbering format */
 104 static const char *format = FORMAT_RN;
 105
 106 /* increment value used to number logical page lines */
 107 static int incr = 1;
 108
 109 /* number of adjacent blank lines to be considered (and numbered) as one */
 110 static unsigned int nblank = 1;
 111
 112 /* whether to restart numbering at logical page delimiters */
 113 static int restart = 1;
 114
 115 /* characters used in separating the line number and the corrsp. text line */
 116 static const char *sep = "\t";
 117
 118 /* initial value used to number logical page lines */
 119 static int startnum = 1;
 120
 121 /* number of characters to be used for the line number */
 122 /* should be unsigned but required signed by `*' precision conversion */
 123 static int width = 6;
 124
 125
 126 int
 127 main(int argc, char *argv[])
 128 {
 129         int c;
 130         long val;
 131         unsigned long uval;
 132         char *ep;
 133
 134         (void)setlocale(LC_ALL, "");
 135
 136         /*
 137          * Note: this implementation strictly conforms to the XBD Utility
 138          * Syntax Guidelines and does not permit the optional `file' operand
 139          * to be intermingled with the options, which is defined in the
 140          * XCU specification (Issue 5) but declared an obsolescent feature that
 141          * will be removed from a future issue.  It shouldn't matter, though.
 142          */
 143         while ((c = getopt(argc, argv, "pb:d:f:h:i:l:n:s:v:w:")) != -1) {
 144                 switch (c) {
 145                 case 'p':
 146                         restart = 0;
 147                         break;
 148                 case 'b':
 149                         parse_numbering(optarg, BODY);
 150                         break;
 151                 case 'd':
 152                         if (optarg[0] != '\0')
 153                                 delim[0] = optarg[0];
 154                         if (optarg[1] != '\0') {
 155                                 delim[1] = optarg[1];
 156                                 /* at most two delimiter characters */
 157                                 if (optarg[2] != '\0') {
 158                                         errx(EXIT_FAILURE,
 159                                             "invalid delim argument -- %s",
 160                                             optarg);
 161                                         /* NOTREACHED */
 162                                 }
 163                         }
 164                         break;
 165                 case 'f':
 166                         parse_numbering(optarg, FOOTER);
 167                         break;
 168                 case 'h':
 169                         parse_numbering(optarg, HEADER);
 170                         break;
 171                 case 'i':
 172                         errno = 0;
 173                         val = strtol(optarg, &ep, 10);
 174                         if ((ep != NULL && *ep != '\0') ||
 175                          ((val == LONG_MIN || val == LONG_MAX) && errno != 0))
 176                                 errx(EXIT_FAILURE,
 177                                     "invalid incr argument -- %s", optarg);
 178                         incr = (int)val;
 179                         break;
 180                 case 'l':
 181                         errno = 0;
 182                         uval = strtoul(optarg, &ep, 10);
 183                         if ((ep != NULL && *ep != '\0') ||
 184                             (uval == ULONG_MAX && errno != 0))
 185                                 errx(EXIT_FAILURE,
 186                                     "invalid num argument -- %s", optarg);
 187                         nblank = (unsigned int)uval;
 188                         break;
 189                 case 'n':
 190                         if (strcmp(optarg, "ln") == 0) {
 191                                 format = FORMAT_LN;
 192                         } else if (strcmp(optarg, "rn") == 0) {
 193                                 format = FORMAT_RN;
 194                         } else if (strcmp(optarg, "rz") == 0) {
 195                                 format = FORMAT_RZ;
 196                         } else
 197                                 errx(EXIT_FAILURE,
 198                                     "illegal format -- %s", optarg);
 199                         break;
 200                 case 's':
 201                         sep = optarg;
 202                         break;
 203                 case 'v':
 204                         errno = 0;
 205                         val = strtol(optarg, &ep, 10);
 206                         if ((ep != NULL && *ep != '\0') ||
 207                          ((val == LONG_MIN || val == LONG_MAX) && errno != 0))
 208                                 errx(EXIT_FAILURE,
 209                                     "invalid startnum value -- %s", optarg);
 210                         startnum = (int)val;
 211                         break;
 212                 case 'w':
 213                         errno = 0;
 214                         val = strtol(optarg, &ep, 10);
 215                         if ((ep != NULL && *ep != '\0') ||
 216                          ((val == LONG_MIN || val == LONG_MAX) && errno != 0))
 217                                 errx(EXIT_FAILURE,
 218                                     "invalid width value -- %s", optarg);
 219                         width = (int)val;
 220                         if (!(width > 0))
 221                                 errx(EXIT_FAILURE,
 222                                     "width argument must be > 0 -- %d",
 223                                     width);
 224                         break;
 225                 case '?':
 226                 default:
 227                         usage(argv[0]);
 228                         /* NOTREACHED */
 229                 }
 230         }
 231         argc -= optind;
 232         argv += optind;
 233
 234         switch (argc) {
 235         case 0:
 236                 break;
 237         case 1:
 238                 if (strcmp(argv[0], "-") != 0 &&
 239                     freopen(argv[0], "r", stdin) == NULL)
 240                         errx(EXIT_FAILURE, "Cannot open `%s'", argv[0]);
 241                 break;
 242         default:
 243                 usage(argv[0]);
 244                 /* NOTREACHED */
 245         }
 246
 247         /* Determine the maximum input line length to operate on. */
 248         if ((val = sysconf(_SC_LINE_MAX)) == -1) /* ignore errno */
 249                 val = LINE_MAX;
 250         /* Allocate sufficient buffer space (including the terminating NUL). */
 251         buffersize = (size_t)val + 1;
 252         if ((buffer = malloc(buffersize)) == NULL)
 253                 errx(EXIT_FAILURE, "Cannot allocate input line buffer");
 254
 255         /* Allocate a buffer suitable for preformatting line number. */
 256         intbuffersize = max((int)INT_STRLEN_MAXIMUM, width) + 1; /* NUL */
 257         if ((intbuffer = malloc(intbuffersize)) == NULL)
 258                 errx(EXIT_FAILURE, "cannot allocate preformatting buffer");
 259
 260         /* Do the work. */
 261         filter();
 262
 263         return EXIT_SUCCESS;
 264         /* NOTREACHED */
 265 }
 266
 267 static void
 268 filter(void)
 269 {
 270         int line;               /* logical line number */
 271         int section;            /* logical page section */
 272         unsigned int adjblank;  /* adjacent blank lines */
 273         int consumed;           /* intbuffer measurement */
 274         int donumber, idx;
 275
 276         adjblank = 0;
 277         line = startnum;
 278         section = BODY;
 279 #ifdef __GNUC__
 280         donumber = 0;   /* avoid bogus `uninitialized' warning */
 281 #endif
 282
 283         while (fgets(buffer, (int)buffersize, stdin) != NULL) {
 284                 for (idx = FOOTER; idx <= NP_LAST; idx++) {
 285                         /* Does it look like a delimiter? */
 286                         if (buffer[2 * idx + 0] == delim[0] &&
 287                             buffer[2 * idx + 1] == delim[1]) {
 288                                 /* Was this the whole line? */
 289                                 if (buffer[2 * idx + 2] == '\n') {
 290                                         section = idx;
 291                                         adjblank = 0;
 292                                         if (restart)
 293                                                 line = startnum;
 294                                         goto nextline;
 295                                 }
 296                         } else {
 297                                 break;
 298                         }
 299                 }
 300
 301                 switch (numbering_properties[section].type) {
 302                 case number_all:
 303                         /*
 304                          * Doing this for number_all only is disputable, but
 305                          * the standard expresses an explicit dependency on
 306                          * `-b a' etc.
 307                          */
 308                         if (buffer[0] == '\n' && ++adjblank < nblank)
 309                                 donumber = 0;
 310                         else
 311                                 donumber = 1, adjblank = 0;
 312                         break;
 313                 case number_nonempty:
 314                         donumber = (buffer[0] != '\n');
 315                         break;
 316                 case number_none:
 317                         donumber = 0;
 318                         break;
 319                 case number_regex:
 320                         donumber =
 321                             (regexec(&numbering_properties[section].expr,
 322                             buffer, 0, NULL, 0) == 0);
 323                         break;
 324                 }
 325
 326                 if (donumber) {
 327                         consumed = snprintf(intbuffer, intbuffersize, format,
 328                             width, line);
 329                         (void)printf("%s%s",
 330                             intbuffer + max(0, consumed - width), sep);
 331                         line += incr;
 332                 } else {
 333                         (void)printf("%*s%*s", width, "", (int)strlen(sep), "");
 334                 }
 335                 (void)printf("%s", buffer);
 336
 337                 if (ferror(stdout))
 338                         errx(EXIT_FAILURE, "output error");
 339 nextline:
 340                 ;
 341         }
 342
 343         if (ferror(stdin))
 344                 errx(EXIT_FAILURE, "input error");
 345 }
 346
 347 /*
 348  * Various support functions.
 349  */
 350
 351 static void
 352 parse_numbering(const char *argstr, int section)
 353 {
 354         int error;
 355         char errorbuf[NL_TEXTMAX];
 356
 357         switch (argstr[0]) {
 358         case 'a':
 359                 numbering_properties[section].type = number_all;
 360                 break;
 361         case 'n':
 362                 numbering_properties[section].type = number_none;
 363                 break;
 364         case 't':
 365                 numbering_properties[section].type = number_nonempty;
 366                 break;
 367         case 'p':
 368                 /* If there was a previous expression, throw it away. */
 369                 if (numbering_properties[section].type == number_regex)
 370                         regfree(&numbering_properties[section].expr);
 371                 else
 372                         numbering_properties[section].type = number_regex;
 373
 374                 /* Compile/validate the supplied regular expression. */
 375                 if ((error = regcomp(&numbering_properties[section].expr,
 376                     &argstr[1], REG_NEWLINE|REG_NOSUB)) != 0) {
 377                         (void)regerror(error,
 378                             &numbering_properties[section].expr,
 379                             errorbuf, sizeof (errorbuf));
 380                         errx(EXIT_FAILURE,
 381                             "%s expr: %s -- %s",
 382                             numbering_properties[section].name, errorbuf,
 383                             &argstr[1]);
 384                 }
 385                 break;
 386         default:
 387                 errx(EXIT_FAILURE,
 388                     "illegal %s line numbering type -- %s",
 389                     numbering_properties[section].name, argstr);
 390         }
 391 }
 392
 393 static void
 394 usage(char* argv0)
 395 {
 396         (void)fprintf(stderr, "Usage: %s [-p] [-b type] [-d delim] [-f type] "
 397             "[-h type] [-i incr] [-l num]\n\t[-n format] [-s sep] "
 398             "[-v startnum] [-w width] [file]\n", argv0);
 399         exit(EXIT_FAILURE);
 400 }