usr.bin/seq/seq.c

   1 /*
   2  * Copyright (c) 2005 The NetBSD Foundation, Inc.
   3  * All rights reserved.
   4  *
   5  * This code is derived from software contributed to The NetBSD Foundation
   6  * by Brian Ginsbach.
   7  *
   8  * Redistribution and use in source and binary forms, with or without
   9  * modification, are permitted provided that the following conditions
  10  * are met:
  11  * 1. Redistributions of source code must retain the above copyright
  12  *    notice, this list of conditions and the following disclaimer.
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in the
  15  *    documentation and/or other materials provided with the distribution.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
  18  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
  19  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  20  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
  21  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  22  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  23  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  24  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  25  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  26  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  27  * POSSIBILITY OF SUCH DAMAGE.
  28  */
  29
  30 #include <sys/cdefs.h>
  31 #ifndef lint
  32 __COPYRIGHT("@(#) Copyright (c) 2005\
  33  The NetBSD Foundation, Inc.  All rights reserved.");
  34 __RCSID("$NetBSD: seq.c,v 1.7 2010/05/27 08:40:19 dholland Exp $");
  35 #endif /* not lint */
  36
  37 #include <ctype.h>
  38 #include <err.h>
  39 #include <errno.h>
  40 #include <math.h>
  41 #include <locale.h>
  42 #include <stdio.h>
  43 #include <stdlib.h>
  44 #include <string.h>
  45 #include <unistd.h>
  46
  47 #define ZERO    '0'
  48 #define SPACE   ' '
  49
  50 #define MAX(a, b)       (((a) < (b))? (b) : (a))
  51 #define ISSIGN(c)       ((int)(c) == '-' || (int)(c) == '+')
  52 #define ISEXP(c)        ((int)(c) == 'e' || (int)(c) == 'E')
  53 #define ISODIGIT(c)     ((int)(c) >= '0' && (int)(c) <= '7')
  54
  55 /* Globals */
  56
  57 const char *decimal_point = ".";        /* default */
  58 char default_format[] = { "%g" };       /* default */
  59
  60 /* Prototypes */
  61
  62 double e_atof(const char *);
  63
  64 int decimal_places(const char *);
  65 int main(int, char *[]);
  66 int numeric(const char *);
  67 int valid_format(const char *);
  68
  69 char *generate_format(double, double, double, int, char);
  70 char *unescape(char *);
  71
  72 /*
  73  * The seq command will print out a numeric sequence from 1, the default,
  74  * to a user specified upper limit by 1.  The lower bound and increment
  75  * maybe indicated by the user on the command line.  The sequence can
  76  * be either whole, the default, or decimal numbers.
  77  */
  78 int
  79 main(int argc, char *argv[])
  80 {
  81         int c = 0, errflg = 0;
  82         int equalize = 0;
  83         double first = 1.0;
  84         double last = 0.0;
  85         double incr = 0.0;
  86         struct lconv *locale;
  87         char *fmt = NULL;
  88         const char *sep = "\n";
  89         const char *term = NULL;
  90         char pad = ZERO;
  91
  92         /* Determine the locale's decimal point. */
  93         locale = localeconv();
  94         if (locale && locale->decimal_point && locale->decimal_point[0] != '\0')
  95                 decimal_point = locale->decimal_point;
  96
  97         /*
  98          * Process options, but handle negative numbers separately
  99          * least they trip up getopt(3).
 100          */
 101         while ((optind < argc) && !numeric(argv[optind]) &&
 102             (c = getopt(argc, argv, "f:hs:t:w")) != -1) {
 103
 104                 switch (c) {
 105                 case 'f':       /* format (plan9) */
 106                         fmt = optarg;
 107                         equalize = 0;
 108                         break;
 109                 case 's':       /* separator (GNU) */
 110                         sep = unescape(optarg);
 111                         break;
 112                 case 't':       /* terminator (new) */
 113                         term = unescape(optarg);
 114                         break;
 115                 case 'w':       /* equal width (plan9) */
 116                         if (!fmt)
 117                                 if (equalize++)
 118                                         pad = SPACE;
 119                         break;
 120                 case 'h':       /* help (GNU) */
 121                 default:
 122                         errflg++;
 123                         break;
 124                 }
 125         }
 126
 127         argc -= optind;
 128         argv += optind;
 129         if (argc < 1 || argc > 3)
 130                 errflg++;
 131
 132         if (errflg) {
 133                 fprintf(stderr,
 134                     "usage: %s [-w] [-f format] [-s string] [-t string] [first [incr]] last\n",
 135                     getprogname());
 136                 exit(1);
 137         }
 138
 139         last = e_atof(argv[argc - 1]);
 140
 141         if (argc > 1)
 142                 first = e_atof(argv[0]);
 143
 144         if (argc > 2) {
 145                 incr = e_atof(argv[1]);
 146                 /* Plan 9/GNU don't do zero */
 147                 if (incr == 0.0)
 148                         errx(1, "zero %screment", (first < last)? "in" : "de");
 149         }
 150
 151         /* default is one for Plan 9/GNU work alike */
 152         if (incr == 0.0)
 153                 incr = (first < last) ? 1.0 : -1.0;
 154
 155         if (incr <= 0.0 && first < last)
 156                 errx(1, "needs positive increment");
 157
 158         if (incr >= 0.0 && first > last)
 159                 errx(1, "needs negative decrement");
 160
 161         if (fmt != NULL) {
 162                 if (!valid_format(fmt))
 163                         errx(1, "invalid format string: `%s'", fmt);
 164                 fmt = unescape(fmt);
 165                 if (!valid_format(fmt))
 166                         errx(1, "invalid format string");
 167                 /*
 168                  * XXX to be bug for bug compatible with Plan 9 add a
 169                  * newline if none found at the end of the format string.
 170                  */
 171         } else
 172                 fmt = generate_format(first, incr, last, equalize, pad);
 173
 174         if (incr > 0) {
 175                 for (; first <= last; first += incr) {
 176                         printf(fmt, first);
 177                         fputs(sep, stdout);
 178                 }
 179         } else {
 180                 for (; first >= last; first += incr) {
 181                         printf(fmt, first);
 182                         fputs(sep, stdout);
 183                 }
 184         }
 185         if (term != NULL)
 186                 fputs(term, stdout);
 187
 188         return (0);
 189 }
 190
 191 /*
 192  * numeric - verify that string is numeric
 193  */
 194 int
 195 numeric(const char *s)
 196 {
 197         int seen_decimal_pt, decimal_pt_len;
 198
 199         /* skip any sign */
 200         if (ISSIGN((unsigned char)*s))
 201                 s++;
 202
 203         seen_decimal_pt = 0;
 204         decimal_pt_len = strlen(decimal_point);
 205         while (*s) {
 206                 if (!isdigit((unsigned char)*s)) {
 207                         if (!seen_decimal_pt &&
 208                             strncmp(s, decimal_point, decimal_pt_len) == 0) {
 209                                 s += decimal_pt_len;
 210                                 seen_decimal_pt = 1;
 211                                 continue;
 212                         }
 213                         if (ISEXP((unsigned char)*s)) {
 214                                 s++;
 215                                 if (ISSIGN((unsigned char)*s)) {
 216                                         s++;
 217                                         continue;
 218                                 }
 219                         }
 220                         break;
 221                 }
 222                 s++;
 223         }
 224         return (*s == '\0');
 225 }
 226
 227 /*
 228  * valid_format - validate user specified format string
 229  */
 230 int
 231 valid_format(const char *fmt)
 232 {
 233         unsigned conversions = 0;
 234
 235         while (*fmt != '\0') {
 236                 /* scan for conversions */
 237                 if (*fmt != '%') {
 238                         fmt++;
 239                         continue;
 240                 }
 241                 fmt++;
 242
 243                 /* allow %% but not things like %10% */
 244                 if (*fmt == '%') {
 245                         fmt++;
 246                         continue;
 247                 }
 248
 249                 /* flags */
 250                 while (*fmt != '\0' && strchr("#0- +'", *fmt)) {
 251                         fmt++;
 252                 }
 253
 254                 /* field width */
 255                 while (*fmt != '\0' && strchr("0123456789", *fmt)) {
 256                         fmt++;
 257                 }
 258
 259                 /* precision */
 260                 if (*fmt == '.') {
 261                         fmt++;
 262                         while (*fmt != '\0' && strchr("0123456789", *fmt)) {
 263                                 fmt++;
 264                         }
 265                 }
 266
 267                 /* conversion */
 268                 switch (*fmt) {
 269                     case 'A':
 270                     case 'a':
 271                     case 'E':
 272                     case 'e':
 273                     case 'F':
 274                     case 'f':
 275                     case 'G':
 276                     case 'g':
 277                         /* floating point formats are accepted */
 278                         conversions++;
 279                         break;
 280                     default:
 281                         /* anything else is not */
 282                         return 0;
 283                 }
 284         }
 285
 286         return (conversions <= 1);
 287 }
 288
 289 /*
 290  * unescape - handle C escapes in a string
 291  */
 292 char *
 293 unescape(char *orig)
 294 {
 295         char c, *cp, *new = orig;
 296         int i;
 297
 298         for (cp = orig; (*orig = *cp); cp++, orig++) {
 299                 if (*cp != '\\')
 300                         continue;
 301
 302                 switch (*++cp) {
 303                 case 'a':       /* alert (bell) */
 304                         *orig = '\a';
 305                         continue;
 306                 case 'b':       /* backspace */
 307                         *orig = '\b';
 308                         continue;
 309                 case 'e':       /* escape */
 310                         *orig = '\e';
 311                         continue;
 312                 case 'f':       /* formfeed */
 313                         *orig = '\f';
 314                         continue;
 315                 case 'n':       /* newline */
 316                         *orig = '\n';
 317                         continue;
 318                 case 'r':       /* carriage return */
 319                         *orig = '\r';
 320                         continue;
 321                 case 't':       /* horizontal tab */
 322                         *orig = '\t';
 323                         continue;
 324                 case 'v':       /* vertical tab */
 325                         *orig = '\v';
 326                         continue;
 327                 case '\\':      /* backslash */
 328                         *orig = '\\';
 329                         continue;
 330                 case '\'':      /* single quote */
 331                         *orig = '\'';
 332                         continue;
 333                 case '\"':      /* double quote */
 334                         *orig = '"';
 335                         continue;
 336                 case '0':
 337                 case '1':
 338                 case '2':
 339                 case '3':       /* octal */
 340                 case '4':
 341                 case '5':
 342                 case '6':
 343                 case '7':       /* number */
 344                         for (i = 0, c = 0;
 345                              ISODIGIT((unsigned char)*cp) && i < 3;
 346                              i++, cp++) {
 347                                 c <<= 3;
 348                                 c |= (*cp - '0');
 349                         }
 350                         *orig = c;
 351                         --cp;
 352                         continue;
 353                 case 'x':       /* hexidecimal number */
 354                         cp++;   /* skip 'x' */
 355                         for (i = 0, c = 0;
 356                              isxdigit((unsigned char)*cp) && i < 2;
 357                              i++, cp++) {
 358                                 c <<= 4;
 359                                 if (isdigit((unsigned char)*cp))
 360                                         c |= (*cp - '0');
 361                                 else
 362                                         c |= ((toupper((unsigned char)*cp) -
 363                                             'A') + 10);
 364                         }
 365                         *orig = c;
 366                         --cp;
 367                         continue;
 368                 default:
 369                         --cp;
 370                         break;
 371                 }
 372         }
 373
 374         return (new);
 375 }
 376
 377 /*
 378  * e_atof - convert an ASCII string to a double
 379  *      exit if string is not a valid double, or if converted value would
 380  *      cause overflow or underflow
 381  */
 382 double
 383 e_atof(const char *num)
 384 {
 385         char *endp;
 386         double dbl;
 387
 388         errno = 0;
 389         dbl = strtod(num, &endp);
 390
 391         if (errno == ERANGE)
 392                 /* under or overflow */
 393                 err(2, "%s", num);
 394         else if (*endp != '\0')
 395                 /* "junk" left in number */
 396                 errx(2, "invalid floating point argument: %s", num);
 397
 398         /* zero shall have no sign */
 399         if (dbl == -0.0)
 400                 dbl = 0;
 401         return (dbl);
 402 }
 403
 404 /*
 405  * decimal_places - count decimal places in a number (string)
 406  */
 407 int
 408 decimal_places(const char *number)
 409 {
 410         int places = 0;
 411         char *dp;
 412
 413         /* look for a decimal point */
 414         if ((dp = strstr(number, decimal_point))) {
 415                 dp += strlen(decimal_point);
 416
 417                 while (isdigit((unsigned char)*dp++))
 418                         places++;
 419         }
 420         return (places);
 421 }
 422
 423 /*
 424  * generate_format - create a format string
 425  *
 426  * XXX to be bug for bug compatable with Plan9 and GNU return "%g"
 427  * when "%g" prints as "%e" (this way no width adjustments are made)
 428  */
 429 char *
 430 generate_format(double first, double incr, double last, int equalize, char pad)
 431 {
 432         static char buf[256];
 433         char cc = '\0';
 434         int precision, width1, width2, places;
 435
 436         if (equalize == 0)
 437                 return (default_format);
 438
 439         /* figure out "last" value printed */
 440         if (first > last)
 441                 last = first - incr * floor((first - last) / incr);
 442         else
 443                 last = first + incr * floor((last - first) / incr);
 444
 445         sprintf(buf, "%g", incr);
 446         if (strchr(buf, 'e'))
 447                 cc = 'e';
 448         precision = decimal_places(buf);
 449
 450         width1 = sprintf(buf, "%g", first);
 451         if (strchr(buf, 'e'))
 452                 cc = 'e';
 453         if ((places = decimal_places(buf)))
 454                 width1 -= (places + strlen(decimal_point));
 455
 456         precision = MAX(places, precision);
 457
 458         width2 = sprintf(buf, "%g", last);
 459         if (strchr(buf, 'e'))
 460                 cc = 'e';
 461         if ((places = decimal_places(buf)))
 462                 width2 -= (places + strlen(decimal_point));
 463
 464         if (precision) {
 465                 sprintf(buf, "%%%c%d.%d%c", pad,
 466                     MAX(width1, width2) + (int) strlen(decimal_point) +
 467                     precision, precision, (cc) ? cc : 'f');
 468         } else {
 469                 sprintf(buf, "%%%c%d%c", pad, MAX(width1, width2),
 470                     (cc) ? cc : 'g');
 471         }
 472
 473         return (buf);
 474 }