shell_cmds/seq/seq.c

   1 /*      $NetBSD: seq.c,v 1.5 2008/07/21 14:19:26 lukem Exp $    */
   2 /*
   3  * Copyright (c) 2005 The NetBSD Foundation, Inc.
   4  * All rights reserved.
   5  *
   6  * This code is derived from software contributed to The NetBSD Foundation
   7  * by Brian Ginsbach.
   8  *
   9  * Redistribution and use in source and binary forms, with or without
  10  * modification, are permitted provided that the following conditions
  11  * are met:
  12  * 1. Redistributions of source code must retain the above copyright
  13  *    notice, this list of conditions and the following disclaimer.
  14  * 2. Redistributions in binary form must reproduce the above copyright
  15  *    notice, this list of conditions and the following disclaimer in the
  16  *    documentation and/or other materials provided with the distribution.
  17  *
  18  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
  19  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
  20  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  21  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
  22  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  23  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  24  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  25  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  26  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  27  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  28  * POSSIBILITY OF SUCH DAMAGE.
  29  */
  30
  31 #include <sys/cdefs.h>
  32 __FBSDID("$FreeBSD: src/usr.bin/seq/seq.c,v 1.2 2010/02/20 01:23:15 delphij Exp $");
  33
  34 #include <ctype.h>
  35 #include <err.h>
  36 #include <errno.h>
  37 #include <math.h>
  38 #include <locale.h>
  39 #include <stdio.h>
  40 #include <stdlib.h>
  41 #include <string.h>
  42 #include <unistd.h>
  43
  44 #define ZERO    '0'
  45 #define SPACE   ' '
  46
  47 #define MAX(a, b)       (((a) < (b))? (b) : (a))
  48 #define ISSIGN(c)       ((int)(c) == '-' || (int)(c) == '+')
  49 #define ISEXP(c)        ((int)(c) == 'e' || (int)(c) == 'E')
  50 #define ISODIGIT(c)     ((int)(c) >= '0' && (int)(c) <= '7')
  51
  52 /* Globals */
  53
  54 const char *decimal_point = ".";        /* default */
  55 char default_format[] = { "%g" };       /* default */
  56
  57 /* Prototypes */
  58
  59 double e_atof(const char *);
  60
  61 int decimal_places(const char *);
  62 int main(int, char *[]);
  63 int numeric(const char *);
  64 int valid_format(const char *);
  65
  66 char *generate_format(double, double, double, int, char);
  67 char *unescape(char *);
  68
  69 /*
  70  * The seq command will print out a numeric sequence from 1, the default,
  71  * to a user specified upper limit by 1.  The lower bound and increment
  72  * maybe indicated by the user on the command line.  The sequence can
  73  * be either whole, the default, or decimal numbers.
  74  */
  75 int
  76 main(int argc, char *argv[])
  77 {
  78         int c = 0, errflg = 0;
  79         int equalize = 0;
  80         double first = 1.0;
  81         double last = 0.0;
  82         double incr = 0.0;
  83         struct lconv *locale;
  84         char *fmt = NULL;
  85         const char *sep = "\n";
  86         const char *term = NULL;
  87         char pad = ZERO;
  88
  89         /* Determine the locale's decimal point. */
  90         locale = localeconv();
  91         if (locale && locale->decimal_point && locale->decimal_point[0] != '\0')
  92                 decimal_point = locale->decimal_point;
  93
  94         /*
  95          * Process options, but handle negative numbers separately
  96          * least they trip up getopt(3).
  97          */
  98         while ((optind < argc) && !numeric(argv[optind]) &&
  99             (c = getopt(argc, argv, "f:hs:t:w")) != -1) {
 100
 101                 switch (c) {
 102                 case 'f':       /* format (plan9) */
 103                         fmt = optarg;
 104                         equalize = 0;
 105                         break;
 106                 case 's':       /* separator (GNU) */
 107                         sep = unescape(optarg);
 108                         break;
 109                 case 't':       /* terminator (new) */
 110                         term = unescape(optarg);
 111                         break;
 112                 case 'w':       /* equal width (plan9) */
 113                         if (!fmt)
 114                                 if (equalize++)
 115                                         pad = SPACE;
 116                         break;
 117                 case 'h':       /* help (GNU) */
 118                 default:
 119                         errflg++;
 120                         break;
 121                 }
 122         }
 123
 124         argc -= optind;
 125         argv += optind;
 126         if (argc < 1 || argc > 3)
 127                 errflg++;
 128
 129         if (errflg) {
 130                 fprintf(stderr,
 131                     "usage: %s [-w] [-f format] [-s string] [-t string] [first [incr]] last\n",
 132                     getprogname());
 133                 exit(1);
 134         }
 135
 136         last = e_atof(argv[argc - 1]);
 137
 138         if (argc > 1)
 139                 first = e_atof(argv[0]);
 140
 141         if (argc > 2) {
 142                 incr = e_atof(argv[1]);
 143                 /* Plan 9/GNU don't do zero */
 144                 if (incr == 0.0)
 145                         errx(1, "zero %screment", (first < last)? "in" : "de");
 146         }
 147
 148         /* default is one for Plan 9/GNU work alike */
 149         if (incr == 0.0)
 150                 incr = (first < last) ? 1.0 : -1.0;
 151
 152         if (incr <= 0.0 && first < last)
 153                 errx(1, "needs positive increment");
 154
 155         if (incr >= 0.0 && first > last)
 156                 errx(1, "needs negative decrement");
 157
 158         if (fmt != NULL) {
 159                 if (!valid_format(fmt))
 160                         errx(1, "invalid format string: `%s'", fmt);
 161                 fmt = unescape(fmt);
 162                 /*
 163                  * XXX to be bug for bug compatible with Plan 9 add a
 164                  * newline if none found at the end of the format string.
 165                  */
 166         } else
 167                 fmt = generate_format(first, incr, last, equalize, pad);
 168
 169         if (incr > 0) {
 170                 for (; first <= last; first += incr) {
 171                         printf(fmt, first);
 172                         fputs(sep, stdout);
 173                 }
 174         } else {
 175                 for (; first >= last; first += incr) {
 176                         printf(fmt, first);
 177                         fputs(sep, stdout);
 178                 }
 179         }
 180         if (term != NULL)
 181                 fputs(term, stdout);
 182
 183         return (0);
 184 }
 185
 186 /*
 187  * numeric - verify that string is numeric
 188  */
 189 int
 190 numeric(const char *s)
 191 {
 192         int seen_decimal_pt, decimal_pt_len;
 193
 194         /* skip any sign */
 195         if (ISSIGN((unsigned char)*s))
 196                 s++;
 197
 198         seen_decimal_pt = 0;
 199         decimal_pt_len = strlen(decimal_point);
 200         while (*s) {
 201                 if (!isdigit((unsigned char)*s)) {
 202                         if (!seen_decimal_pt &&
 203                             strncmp(s, decimal_point, decimal_pt_len) == 0) {
 204                                 s += decimal_pt_len;
 205                                 seen_decimal_pt = 1;
 206                                 continue;
 207                         }
 208                         if (ISEXP((unsigned char)*s)) {
 209                                 s++;
 210                                 if (ISSIGN((unsigned char)*s) ||
 211                                     isdigit((unsigned char)*s)) {
 212                                         s++;
 213                                         continue;
 214                                 }
 215                         }
 216                         break;
 217                 }
 218                 s++;
 219         }
 220         return (*s == '\0');
 221 }
 222
 223 /*
 224  * valid_format - validate user specified format string
 225  */
 226 int
 227 valid_format(const char *fmt)
 228 {
 229         int conversions = 0;
 230
 231         while (*fmt != '\0') {
 232                 /* scan for conversions */
 233                 if (*fmt != '\0' && *fmt != '%') {
 234                         do {
 235                                 fmt++;
 236                         } while (*fmt != '\0' && *fmt != '%');
 237                 }
 238                 /* scan a conversion */
 239                 if (*fmt != '\0') {
 240                         do {
 241                                 fmt++;
 242
 243                                 /* ok %% */
 244                                 if (*fmt == '%') {
 245                                         fmt++;
 246                                         break;
 247                                 }
 248                                 /* valid conversions */
 249                                 if (strchr("eEfgG", *fmt) &&
 250                                     conversions++ < 1) {
 251                                         fmt++;
 252                                         break;
 253                                 }
 254                                 /* flags, width and precsision */
 255                                 if (isdigit((unsigned char)*fmt) ||
 256                                     strchr("+- 0#.", *fmt))
 257                                         continue;
 258
 259                                 /* oops! bad conversion format! */
 260                                 return (0);
 261                         } while (*fmt != '\0');
 262                 }
 263         }
 264
 265         return (conversions <= 1);
 266 }
 267
 268 /*
 269  * unescape - handle C escapes in a string
 270  */
 271 char *
 272 unescape(char *orig)
 273 {
 274         char c, *cp, *new = orig;
 275         int i;
 276
 277         for (cp = orig; (*orig = *cp); cp++, orig++) {
 278                 if (*cp != '\\')
 279                         continue;
 280
 281                 switch (*++cp) {
 282                 case 'a':       /* alert (bell) */
 283                         *orig = '\a';
 284                         continue;
 285                 case 'b':       /* backspace */
 286                         *orig = '\b';
 287                         continue;
 288                 case 'e':       /* escape */
 289                         *orig = '\e';
 290                         continue;
 291                 case 'f':       /* formfeed */
 292                         *orig = '\f';
 293                         continue;
 294                 case 'n':       /* newline */
 295                         *orig = '\n';
 296                         continue;
 297                 case 'r':       /* carriage return */
 298                         *orig = '\r';
 299                         continue;
 300                 case 't':       /* horizontal tab */
 301                         *orig = '\t';
 302                         continue;
 303                 case 'v':       /* vertical tab */
 304                         *orig = '\v';
 305                         continue;
 306                 case '\\':      /* backslash */
 307                         *orig = '\\';
 308                         continue;
 309                 case '\'':      /* single quote */
 310                         *orig = '\'';
 311                         continue;
 312                 case '\"':      /* double quote */
 313                         *orig = '"';
 314                         continue;
 315                 case '0':
 316                 case '1':
 317                 case '2':
 318                 case '3':       /* octal */
 319                 case '4':
 320                 case '5':
 321                 case '6':
 322                 case '7':       /* number */
 323                         for (i = 0, c = 0;
 324                              ISODIGIT((unsigned char)*cp) && i < 3;
 325                              i++, cp++) {
 326                                 c <<= 3;
 327                                 c |= (*cp - '0');
 328                         }
 329                         *orig = c;
 330                         --cp;
 331                         continue;
 332                 case 'x':       /* hexidecimal number */
 333                         cp++;   /* skip 'x' */
 334                         for (i = 0, c = 0;
 335                              isxdigit((unsigned char)*cp) && i < 2;
 336                              i++, cp++) {
 337                                 c <<= 4;
 338                                 if (isdigit((unsigned char)*cp))
 339                                         c |= (*cp - '0');
 340                                 else
 341                                         c |= ((toupper((unsigned char)*cp) -
 342                                             'A') + 10);
 343                         }
 344                         *orig = c;
 345                         --cp;
 346                         continue;
 347                 default:
 348                         --cp;
 349                         break;
 350                 }
 351         }
 352
 353         return (new);
 354 }
 355
 356 /*
 357  * e_atof - convert an ASCII string to a double
 358  *      exit if string is not a valid double, or if converted value would
 359  *      cause overflow or underflow
 360  */
 361 double
 362 e_atof(const char *num)
 363 {
 364         char *endp;
 365         double dbl;
 366
 367         errno = 0;
 368         dbl = strtod(num, &endp);
 369
 370         if (errno == ERANGE)
 371                 /* under or overflow */
 372                 err(2, "%s", num);
 373         else if (*endp != '\0')
 374                 /* "junk" left in number */
 375                 errx(2, "invalid floating point argument: %s", num);
 376
 377         /* zero shall have no sign */
 378         if (dbl == -0.0)
 379                 dbl = 0;
 380         return (dbl);
 381 }
 382
 383 /*
 384  * decimal_places - count decimal places in a number (string)
 385  */
 386 int
 387 decimal_places(const char *number)
 388 {
 389         int places = 0;
 390         char *dp;
 391
 392         /* look for a decimal point */
 393         if ((dp = strstr(number, decimal_point))) {
 394                 dp += strlen(decimal_point);
 395
 396                 while (isdigit((unsigned char)*dp++))
 397                         places++;
 398         }
 399         return (places);
 400 }
 401
 402 /*
 403  * generate_format - create a format string
 404  *
 405  * XXX to be bug for bug compatable with Plan9 and GNU return "%g"
 406  * when "%g" prints as "%e" (this way no width adjustments are made)
 407  */
 408 char *
 409 generate_format(double first, double incr, double last, int equalize, char pad)
 410 {
 411         static char buf[256];
 412         char cc = '\0';
 413         int precision, width1, width2, places;
 414
 415         if (equalize == 0)
 416                 return (default_format);
 417
 418         /* figure out "last" value printed */
 419         if (first > last)
 420                 last = first - incr * floor((first - last) / incr);
 421         else
 422                 last = first + incr * floor((last - first) / incr);
 423
 424         sprintf(buf, "%g", incr);
 425         if (strchr(buf, 'e'))
 426                 cc = 'e';
 427         precision = decimal_places(buf);
 428
 429         width1 = sprintf(buf, "%g", first);
 430         if (strchr(buf, 'e'))
 431                 cc = 'e';
 432         if ((places = decimal_places(buf)))
 433                 width1 -= (places + strlen(decimal_point));
 434
 435         precision = MAX(places, precision);
 436
 437         width2 = sprintf(buf, "%g", last);
 438         if (strchr(buf, 'e'))
 439                 cc = 'e';
 440         if ((places = decimal_places(buf)))
 441                 width2 -= (places + strlen(decimal_point));
 442
 443         if (precision) {
 444                 sprintf(buf, "%%%c%d.%d%c", pad,
 445                     MAX(width1, width2) + (int) strlen(decimal_point) +
 446                     precision, precision, (cc) ? cc : 'f');
 447         } else {
 448                 sprintf(buf, "%%%c%d%c", pad, MAX(width1, width2),
 449                     (cc) ? cc : 'g');
 450         }
 451
 452         return (buf);
 453 }