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 1.4 2008/04/30 14:22:14 ginsbach 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                 /*
 166                  * XXX to be bug for bug compatible with Plan 9 add a
 167                  * newline if none found at the end of the format string.
 168                  */
 169         } else
 170                 fmt = generate_format(first, incr, last, equalize, pad);
 171
 172         if (incr > 0) {
 173                 for (; first <= last; first += incr) {
 174                         printf(fmt, first);
 175                         fputs(sep, stdout);
 176                 }
 177         } else {
 178                 for (; first >= last; first += incr) {
 179                         printf(fmt, first);
 180                         fputs(sep, stdout);
 181                 }
 182         }
 183         if (term != NULL)
 184                 fputs(term, stdout);
 185
 186         return (0);
 187 }
 188
 189 /*
 190  * numeric - verify that string is numeric
 191  */
 192 int
 193 numeric(const char *s)
 194 {
 195         int seen_decimal_pt, decimal_pt_len;
 196
 197         /* skip any sign */
 198         if (ISSIGN((unsigned char)*s))
 199                 s++;
 200
 201         seen_decimal_pt = 0;
 202         decimal_pt_len = strlen(decimal_point);
 203         while (*s) {
 204                 if (!isdigit((unsigned char)*s)) {
 205                         if (!seen_decimal_pt &&
 206                             strncmp(s, decimal_point, decimal_pt_len) == 0) {
 207                                 s += decimal_pt_len;
 208                                 seen_decimal_pt = 1;
 209                                 continue;
 210                         }
 211                         if (ISEXP((unsigned char)*s)) {
 212                                 s++;
 213                                 if (ISSIGN((unsigned char)*s)) {
 214                                         s++;
 215                                         continue;
 216                                 }
 217                         }
 218                         break;
 219                 }
 220                 s++;
 221         }
 222         return (*s == '\0');
 223 }
 224
 225 /*
 226  * valid_format - validate user specified format string
 227  */
 228 int
 229 valid_format(const char *fmt)
 230 {
 231         int conversions = 0;
 232
 233         while (*fmt != '\0') {
 234                 /* scan for conversions */
 235                 if (*fmt != '\0' && *fmt != '%') {
 236                         do {
 237                                 fmt++;
 238                         } while (*fmt != '\0' && *fmt != '%');
 239                 }
 240                 /* scan a conversion */
 241                 if (*fmt != '\0') {
 242                         do {
 243                                 fmt++;
 244
 245                                 /* ok %% */
 246                                 if (*fmt == '%') {
 247                                         fmt++;
 248                                         break;
 249                                 }
 250                                 /* valid conversions */
 251                                 if (strchr("eEfgG", *fmt) &&
 252                                     conversions++ < 1) {
 253                                         fmt++;
 254                                         break;
 255                                 }
 256                                 /* flags, width and precsision */
 257                                 if (isdigit((unsigned char)*fmt) ||
 258                                     strchr("+- 0#.", *fmt))
 259                                         continue;
 260
 261                                 /* oops! bad conversion format! */
 262                                 return (0);
 263                         } while (*fmt != '\0');
 264                 }
 265         }
 266
 267         return (conversions <= 1);
 268 }
 269
 270 /*
 271  * unescape - handle C escapes in a string
 272  */
 273 char *
 274 unescape(char *orig)
 275 {
 276         char c, *cp, *new = orig;
 277         int i;
 278
 279         for (cp = orig; (*orig = *cp); cp++, orig++) {
 280                 if (*cp != '\\')
 281                         continue;
 282
 283                 switch (*++cp) {
 284                 case 'a':       /* alert (bell) */
 285                         *orig = '\a';
 286                         continue;
 287                 case 'b':       /* backspace */
 288                         *orig = '\b';
 289                         continue;
 290                 case 'e':       /* escape */
 291                         *orig = '\e';
 292                         continue;
 293                 case 'f':       /* formfeed */
 294                         *orig = '\f';
 295                         continue;
 296                 case 'n':       /* newline */
 297                         *orig = '\n';
 298                         continue;
 299                 case 'r':       /* carriage return */
 300                         *orig = '\r';
 301                         continue;
 302                 case 't':       /* horizontal tab */
 303                         *orig = '\t';
 304                         continue;
 305                 case 'v':       /* vertical tab */
 306                         *orig = '\v';
 307                         continue;
 308                 case '\\':      /* backslash */
 309                         *orig = '\\';
 310                         continue;
 311                 case '\'':      /* single quote */
 312                         *orig = '\'';
 313                         continue;
 314                 case '\"':      /* double quote */
 315                         *orig = '"';
 316                         continue;
 317                 case '0':
 318                 case '1':
 319                 case '2':
 320                 case '3':       /* octal */
 321                 case '4':
 322                 case '5':
 323                 case '6':
 324                 case '7':       /* number */
 325                         for (i = 0, c = 0;
 326                              ISODIGIT((unsigned char)*cp) && i < 3;
 327                              i++, cp++) {
 328                                 c <<= 3;
 329                                 c |= (*cp - '0');
 330                         }
 331                         *orig = c;
 332                         --cp;
 333                         continue;
 334                 case 'x':       /* hexidecimal number */
 335                         cp++;   /* skip 'x' */
 336                         for (i = 0, c = 0;
 337                              isxdigit((unsigned char)*cp) && i < 2;
 338                              i++, cp++) {
 339                                 c <<= 4;
 340                                 if (isdigit((unsigned char)*cp))
 341                                         c |= (*cp - '0');
 342                                 else
 343                                         c |= ((toupper((unsigned char)*cp) -
 344                                             'A') + 10);
 345                         }
 346                         *orig = c;
 347                         --cp;
 348                         continue;
 349                 default:
 350                         --cp;
 351                         break;
 352                 }
 353         }
 354
 355         return (new);
 356 }
 357
 358 /*
 359  * e_atof - convert an ASCII string to a double
 360  *      exit if string is not a valid double, or if converted value would
 361  *      cause overflow or underflow
 362  */
 363 double
 364 e_atof(const char *num)
 365 {
 366         char *endp;
 367         double dbl;
 368
 369         errno = 0;
 370         dbl = strtod(num, &endp);
 371
 372         if (errno == ERANGE)
 373                 /* under or overflow */
 374                 err(2, "%s", num);
 375         else if (*endp != '\0')
 376                 /* "junk" left in number */
 377                 errx(2, "invalid floating point argument: %s", num);
 378
 379         /* zero shall have no sign */
 380         if (dbl == -0.0)
 381                 dbl = 0;
 382         return (dbl);
 383 }
 384
 385 /*
 386  * decimal_places - count decimal places in a number (string)
 387  */
 388 int
 389 decimal_places(const char *number)
 390 {
 391         int places = 0;
 392         char *dp;
 393
 394         /* look for a decimal point */
 395         if ((dp = strstr(number, decimal_point))) {
 396                 dp += strlen(decimal_point);
 397
 398                 while (isdigit((unsigned char)*dp++))
 399                         places++;
 400         }
 401         return (places);
 402 }
 403
 404 /*
 405  * generate_format - create a format string
 406  *
 407  * XXX to be bug for bug compatable with Plan9 and GNU return "%g"
 408  * when "%g" prints as "%e" (this way no width adjustments are made)
 409  */
 410 char *
 411 generate_format(double first, double incr, double last, int equalize, char pad)
 412 {
 413         static char buf[256];
 414         char cc = '\0';
 415         int precision, width1, width2, places;
 416
 417         if (equalize == 0)
 418                 return (default_format);
 419
 420         /* figure out "last" value printed */
 421         if (first > last)
 422                 last = first - incr * floor((first - last) / incr);
 423         else
 424                 last = first + incr * floor((last - first) / incr);
 425
 426         sprintf(buf, "%g", incr);
 427         if (strchr(buf, 'e'))
 428                 cc = 'e';
 429         precision = decimal_places(buf);
 430
 431         width1 = sprintf(buf, "%g", first);
 432         if (strchr(buf, 'e'))
 433                 cc = 'e';
 434         if ((places = decimal_places(buf)))
 435                 width1 -= (places + strlen(decimal_point));
 436
 437         precision = MAX(places, precision);
 438
 439         width2 = sprintf(buf, "%g", last);
 440         if (strchr(buf, 'e'))
 441                 cc = 'e';
 442         if ((places = decimal_places(buf)))
 443                 width2 -= (places + strlen(decimal_point));
 444
 445         if (precision) {
 446                 sprintf(buf, "%%%c%d.%d%c", pad,
 447                     MAX(width1, width2) + (int) strlen(decimal_point) +
 448                     precision, precision, (cc) ? cc : 'f');
 449         } else {
 450                 sprintf(buf, "%%%c%d%c", pad, MAX(width1, width2),
 451                     (cc) ? cc : 'g');
 452         }
 453
 454         return (buf);
 455 }