usr.bin/seq/seq.c

   1 /*
   2  * Copyright (c) 2005 The DragonFly Project.  All rights reserved.
   3  *
   4  * This code is derived from software contributed to The DragonFly Project
   5  * by Brian Ginsbach.
   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 DragonFly Project nor the names of its
  16  *    contributors may be used to endorse or promote products derived
  17  *    from this software without specific prior written permission.
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  21  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
  22  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
  23  * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
  24  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
  25  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  26  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
  27  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  28  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
  29  * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  30  * SUCH DAMAGE.
  31  *
  32  * $DragonFly: src/usr.bin/seq/seq.c,v 1.1 2005/01/22 19:09:40 joerg Exp $
  33  */
  34
  35 #include <ctype.h>
  36 #include <err.h>
  37 #include <errno.h>
  38 #include <math.h>
  39 #include <locale.h>
  40 #include <stdio.h>
  41 #include <stdlib.h>
  42 #include <string.h>
  43 #include <unistd.h>
  44
  45 #define ZERO    '0'
  46 #define SPACE   ' '
  47
  48 #define MAX(a, b)       (((a) < (b))? (b) : (a))
  49 #define ISSIGN(c)       ((int)(c) == '-' || (int)(c) == '+')
  50 #define ISEXP(c)        ((int)(c) == 'e' || (int)(c) == 'E')
  51 #define ISODIGIT(c)     ((int)(c) >= '0' && (int)(c) <= '7')
  52
  53 /* Globals */
  54
  55 const char *decimal_point = ".";        /* default */
  56 char default_format[] = { "%g" };       /* default */
  57
  58 /* Prototypes */
  59
  60 double  e_atof(const char *);
  61
  62 int     decimal_places(const 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 [-f format] [-s str] [-t str] [-w] [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 != '\0') {
 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                                         s++;
 212                                         continue;
 213                                 }
 214                         }
 215                         break;
 216                 }
 217                 s++;
 218         }
 219         return(*s == '\0');
 220 }
 221
 222 /*
 223  * valid_format - validate user specified format string
 224  */
 225 int
 226 valid_format(const char *fmt)
 227 {
 228         int conversions = 0;
 229
 230         while (*fmt != '\0') {
 231                 /* scan for conversions */
 232                 if (*fmt != '\0' && *fmt != '%') {
 233                         do {
 234                                 fmt++;
 235                         } while (*fmt != '\0' && *fmt != '%');
 236                 }
 237                 /* scan a conversion */
 238                 if (*fmt != '\0') {
 239                         do {
 240                                 fmt++;
 241
 242                                 /* ok %% */
 243                                 if (*fmt == '%') {
 244                                         fmt++;
 245                                         break;
 246                                 }
 247                                 /* valid conversions */
 248                                 if (strchr("eEfgG", *fmt) &&
 249                                     conversions++ < 1) {
 250                                         fmt++;
 251                                         break;
 252                                 }
 253                                 /* flags, width and precsision */
 254                                 if (isdigit((unsigned char)*fmt) ||
 255                                     strchr("+- 0#.", *fmt))
 256                                         continue;
 257
 258                                 /* oops! bad conversion format! */
 259                                 return(0);
 260                         } while (*fmt != '\0');
 261                 }
 262         }
 263
 264         return(conversions <= 1);
 265 }
 266
 267 /*
 268  * unescape - handle C escapes in a string
 269  */
 270 char *
 271 unescape(char *orig)
 272 {
 273         char c, *cp, *new = orig;
 274         int i;
 275
 276         for (cp = orig; (*orig = *cp) != '\0'; cp++, orig++) {
 277                 if (*cp != '\\')
 278                         continue;
 279
 280                 switch (*++cp) {
 281                 case 'a':       /* alert (bell) */
 282                         *orig = '\a';
 283                         continue;
 284                 case 'b':       /* backspace */
 285                         *orig = '\b';
 286                         continue;
 287                 case 'e':       /* escape */
 288                         *orig = '\e';
 289                         continue;
 290                 case 'f':       /* formfeed */
 291                         *orig = '\f';
 292                         continue;
 293                 case 'n':       /* newline */
 294                         *orig = '\n';
 295                         continue;
 296                 case 'r':       /* carriage return */
 297                         *orig = '\r';
 298                         continue;
 299                 case 't':       /* horizontal tab */
 300                         *orig = '\t';
 301                         continue;
 302                 case 'v':       /* vertical tab */
 303                         *orig = '\v';
 304                         continue;
 305                 case '\\':      /* backslash */
 306                         *orig = '\\';
 307                         continue;
 308                 case '\'':      /* single quote */
 309                         *orig = '\'';
 310                         continue;
 311                 case '\"':      /* double quote */
 312                         *orig = '"';
 313                         continue;
 314                 case '0':
 315                 case '1':
 316                 case '2':
 317                 case '3':       /* octal */
 318                 case '4':
 319                 case '5':
 320                 case '6':
 321                 case '7':       /* number */
 322                         for (i = 0, c = 0;
 323                              ISODIGIT((unsigned char)*cp) && i < 3;
 324                              i++, cp++) {
 325                                 c <<= 3;
 326                                 c |= (*cp - '0');
 327                         }
 328                         *orig = c;
 329                         continue;
 330                 case 'x':       /* hexidecimal number */
 331                         cp++;   /* skip 'x' */
 332                         for (i = 0, c = 0;
 333                              isxdigit((unsigned char)*cp) && i < 2;
 334                              i++, cp++) {
 335                                 c <<= 4;
 336                                 if (isdigit((unsigned char)*cp))
 337                                         c |= (*cp - '0');
 338                                 else
 339                                         c |= ((toupper((unsigned char)*cp) -
 340                                             'A') + 10);
 341                         }
 342                         *orig = c;
 343                         continue;
 344                 default:
 345                         --cp;
 346                         break;
 347                 }
 348         }
 349
 350         return(new);
 351 }
 352
 353 /*
 354  * e_atof - convert an ASCII string to a double
 355  *      exit if string is not a valid double, or if converted value would
 356  *      cause overflow or underflow
 357  */
 358 double
 359 e_atof(const char *num)
 360 {
 361         char *endp;
 362         double dbl;
 363
 364         errno = 0;
 365         dbl = strtod(num, &endp);
 366
 367         if (errno == ERANGE)
 368                 /* under or overflow */
 369                 err(2, "%s", num);
 370         else if (*endp != '\0')
 371                 /* "junk" left in number */
 372                 errx(2, "invalid floating point argument: %s", num);
 373
 374         /* zero shall have no sign */
 375         if (dbl == -0.0)
 376                 dbl = 0;
 377         return(dbl);
 378 }
 379
 380 /*
 381  * decimal_places - count decimal places in a number (string)
 382  */
 383 int
 384 decimal_places(const char *number)
 385 {
 386         int places = 0;
 387         char *dp;
 388
 389         /* look for a decimal point */
 390         if ((dp = strstr(number, decimal_point)) != NULL) {
 391                 dp += strlen(decimal_point);
 392
 393                 while (isdigit((unsigned char)*dp++))
 394                         places++;
 395         }
 396         return(places);
 397 }
 398
 399 /*
 400  * generate_format - create a format string
 401  *
 402  * XXX to be bug for bug compatable with Plan9 and GNU return "%g"
 403  * when "%g" prints as "%e" (this way no width adjustments are made)
 404  */
 405 char *
 406 generate_format(double first, double incr, double last, int equalize, char pad)
 407 {
 408         static char buf[256];
 409         char cc = '\0';
 410         int precision, width1, width2, places;
 411
 412         if (equalize == 0)
 413                 return(default_format);
 414
 415         /* figure out "last" value printed */
 416         if (first > last)
 417                 last = first - incr * floor((first - last) / incr);
 418         else
 419                 last = first + incr * floor((last - first) / incr);
 420
 421         snprintf(buf, sizeof(buf), "%g", incr);
 422         if (strchr(buf, 'e'))
 423                 cc = 'e';
 424         precision = decimal_places(buf);
 425
 426         width1 = snprintf(buf, sizeof(buf), "%g", first);
 427         if (strchr(buf, 'e'))
 428                 cc = 'e';
 429         if ((places = decimal_places(buf)))
 430                 width1 -= (places + strlen(decimal_point));
 431
 432         precision = MAX(places, precision);
 433
 434         width2 = snprintf(buf, sizeof(buf), "%g", last);
 435         if (strchr(buf, 'e'))
 436                 cc = 'e';
 437         if ((places = decimal_places(buf)))
 438                 width2 -= (places + strlen(decimal_point));
 439
 440         if (precision) {
 441                 snprintf(buf, sizeof(buf), "%%%c%d.%d%c", pad,
 442                     MAX(width1, width2) + (int) strlen(decimal_point) +
 443                     precision, precision, (cc) ? cc : 'f');
 444         } else {
 445                 snprintf(buf, sizeof(buf), "%%%c%d%c", pad,
 446                     MAX(width1, width2), (cc) ? cc : 'g');
 447         }
 448
 449         return(buf);
 450 }