coreutils/sort.c

   1 /* vi: set sw=4 ts=4: */
   2 /*
   3  * SuS3 compliant sort implementation for busybox
   4  *
   5  * Copyright (C) 2004 by Rob Landley <rob@landley.net>
   6  *
   7  * MAINTAINER: Rob Landley <rob@landley.net>
   8  *
   9  * Licensed under GPLv2 or later, see file LICENSE in this source tree.
  10  *
  11  * See SuS3 sort standard at:
  12  * http://www.opengroup.org/onlinepubs/007904975/utilities/sort.html
  13  */
  14 //config:config SORT
  15 //config:       bool "sort"
  16 //config:       default y
  17 //config:       help
  18 //config:         sort is used to sort lines of text in specified files.
  19 //config:
  20 //config:config FEATURE_SORT_BIG
  21 //config:       bool "Full SuSv3 compliant sort (support -ktcsbdfiozgM)"
  22 //config:       default y
  23 //config:       depends on SORT
  24 //config:       help
  25 //config:         Without this, sort only supports -r, -u, and an integer version
  26 //config:         of -n. Selecting this adds sort keys, floating point support, and
  27 //config:         more. This adds a little over 3k to a nonstatic build on x86.
  28 //config:
  29 //config:         The SuSv3 sort standard is available at:
  30 //config:         http://www.opengroup.org/onlinepubs/007904975/utilities/sort.html
  31
  32 //applet:IF_SORT(APPLET_NOEXEC(sort, sort, BB_DIR_USR_BIN, BB_SUID_DROP, sort))
  33
  34 //kbuild:lib-$(CONFIG_SORT) += sort.o
  35
  36 //usage:#define sort_trivial_usage
  37 //usage:       "[-nru"
  38 //usage:        IF_FEATURE_SORT_BIG("gMcszbdfiokt] [-o FILE] [-k start[.offset][opts][,end[.offset][opts]] [-t CHAR")
  39 //usage:       "] [FILE]..."
  40 //usage:#define sort_full_usage "\n\n"
  41 //usage:       "Sort lines of text\n"
  42 //usage:        IF_FEATURE_SORT_BIG(
  43 //usage:     "\n        -o FILE Output to FILE"
  44 //usage:     "\n        -c      Check whether input is sorted"
  45 //usage:     "\n        -b      Ignore leading blanks"
  46 //usage:     "\n        -f      Ignore case"
  47 //usage:     "\n        -i      Ignore unprintable characters"
  48 //usage:     "\n        -d      Dictionary order (blank or alphanumeric only)"
  49 //usage:     "\n        -g      General numerical sort"
  50 //usage:     "\n        -M      Sort month"
  51 //usage:        )
  52 //-h, --human-numeric-sort: compare human readable numbers (e.g., 2K 1G)
  53 //usage:     "\n        -n      Sort numbers"
  54 //usage:        IF_FEATURE_SORT_BIG(
  55 //usage:     "\n        -t CHAR Field separator"
  56 //usage:     "\n        -k N[,M] Sort by Nth field"
  57 //usage:        )
  58 //usage:     "\n        -r      Reverse sort order"
  59 //usage:        IF_FEATURE_SORT_BIG(
  60 //usage:     "\n        -s      Stable (don't sort ties alphabetically)"
  61 //usage:        )
  62 //usage:     "\n        -u      Suppress duplicate lines"
  63 //usage:        IF_FEATURE_SORT_BIG(
  64 //usage:     "\n        -z      Lines are terminated by NUL, not newline"
  65 ////usage:     "\n      -m      Ignored for GNU compatibility"
  66 ////usage:     "\n      -S BUFSZ Ignored for GNU compatibility"
  67 ////usage:     "\n      -T TMPDIR Ignored for GNU compatibility"
  68 //usage:        )
  69 //usage:
  70 //usage:#define sort_example_usage
  71 //usage:       "$ echo -e \"e\\nf\\nb\\nd\\nc\\na\" | sort\n"
  72 //usage:       "a\n"
  73 //usage:       "b\n"
  74 //usage:       "c\n"
  75 //usage:       "d\n"
  76 //usage:       "e\n"
  77 //usage:       "f\n"
  78 //usage:        IF_FEATURE_SORT_BIG(
  79 //usage:                "$ echo -e \"c 3\\nb 2\\nd 2\" | $SORT -k 2,2n -k 1,1r\n"
  80 //usage:                "d 2\n"
  81 //usage:                "b 2\n"
  82 //usage:                "c 3\n"
  83 //usage:        )
  84 //usage:       ""
  85
  86 #include "libbb.h"
  87
  88 /* This is a NOEXEC applet. Be very careful! */
  89
  90
  91 /*
  92         sort [-m][-o output][-bdfinru][-t char][-k keydef]... [file...]
  93         sort -c [-bdfinru][-t char][-k keydef][file]
  94 */
  95
  96 /* These are sort types */
  97 static const char OPT_STR[] ALIGN1 = "ngMucszbrdfimS:T:o:k:*t:";
  98 enum {
  99         FLAG_n  = 1,            /* Numeric sort */
 100         FLAG_g  = 2,            /* Sort using strtod() */
 101         FLAG_M  = 4,            /* Sort date */
 102 /* ucsz apply to root level only, not keys.  b at root level implies bb */
 103         FLAG_u  = 8,            /* Unique */
 104         FLAG_c  = 0x10,         /* Check: no output, exit(!ordered) */
 105         FLAG_s  = 0x20,         /* Stable sort, no ascii fallback at end */
 106         FLAG_z  = 0x40,         /* Input and output is NUL terminated, not \n */
 107 /* These can be applied to search keys, the previous four can't */
 108         FLAG_b  = 0x80,         /* Ignore leading blanks */
 109         FLAG_r  = 0x100,        /* Reverse */
 110         FLAG_d  = 0x200,        /* Ignore !(isalnum()|isspace()) */
 111         FLAG_f  = 0x400,        /* Force uppercase */
 112         FLAG_i  = 0x800,        /* Ignore !isprint() */
 113         FLAG_m  = 0x1000,       /* ignored: merge already sorted files; do not sort */
 114         FLAG_S  = 0x2000,       /* ignored: -S, --buffer-size=SIZE */
 115         FLAG_T  = 0x4000,       /* ignored: -T, --temporary-directory=DIR */
 116         FLAG_o  = 0x8000,
 117         FLAG_k  = 0x10000,
 118         FLAG_t  = 0x20000,
 119         FLAG_bb = 0x80000000,   /* Ignore trailing blanks  */
 120 };
 121
 122 #if ENABLE_FEATURE_SORT_BIG
 123 static char key_separator;
 124
 125 static struct sort_key {
 126         struct sort_key *next_key;  /* linked list */
 127         unsigned range[4];          /* start word, start char, end word, end char */
 128         unsigned flags;
 129 } *key_list;
 130
 131 static char *get_key(char *str, struct sort_key *key, int flags)
 132 {
 133         int start = start; /* for compiler */
 134         int end;
 135         int len, j;
 136         unsigned i;
 137
 138         /* Special case whole string, so we don't have to make a copy */
 139         if (key->range[0] == 1 && !key->range[1] && !key->range[2] && !key->range[3]
 140          && !(flags & (FLAG_b | FLAG_d | FLAG_f | FLAG_i | FLAG_bb))
 141         ) {
 142                 return str;
 143         }
 144
 145         /* Find start of key on first pass, end on second pass */
 146         len = strlen(str);
 147         for (j = 0; j < 2; j++) {
 148                 if (!key->range[2*j])
 149                         end = len;
 150                 /* Loop through fields */
 151                 else {
 152                         unsigned char ch = 0;
 153
 154                         end = 0;
 155                         for (i = 1; i < key->range[2*j] + j; i++) {
 156                                 if (key_separator) {
 157                                         /* Skip body of key and separator */
 158                                         while ((ch = str[end]) != '\0') {
 159                                                         end++;
 160                                                 if (ch == key_separator)
 161                                                         break;
 162                                         }
 163                                 } else {
 164                                         /* Skip leading blanks */
 165                                         while (isspace(str[end]))
 166                                                 end++;
 167                                         /* Skip body of key */
 168                                         while (str[end] != '\0') {
 169                                                 if (isspace(str[end]))
 170                                                         break;
 171                                                 end++;
 172                                         }
 173                                 }
 174                         }
 175                         /* Remove last delim: "abc:def:" => "abc:def" */
 176                         if (j && ch) {
 177                                 //if (str[end-1] != key_separator)
 178                                 //  bb_error_msg(_and_die("BUG! "
 179                                 //  "str[start:%d,end:%d]:'%.*s'",
 180                                 //  start, end, (int)(end-start), &str[start]);
 181                                 end--;
 182                         }
 183                 }
 184                 if (!j) start = end;
 185         }
 186         /* Strip leading whitespace if necessary */
 187         if (flags & FLAG_b)
 188                 /* not using skip_whitespace() for speed */
 189                 while (isspace(str[start])) start++;
 190         /* Strip trailing whitespace if necessary */
 191         if (flags & FLAG_bb)
 192                 while (end > start && isspace(str[end-1])) end--;
 193         /* -kSTART,N.ENDCHAR: honor ENDCHAR (1-based) */
 194         if (key->range[3]) {
 195                 end = key->range[3];
 196                 if (end > len) end = len;
 197         }
 198         /* -kN.STARTCHAR[,...]: honor STARTCHAR (1-based) */
 199         if (key->range[1]) {
 200                 start += key->range[1] - 1;
 201                 if (start > len) start = len;
 202         }
 203         /* Make the copy */
 204         if (end < start)
 205                 end = start;
 206         str = xstrndup(str+start, end-start);
 207         /* Handle -d */
 208         if (flags & FLAG_d) {
 209                 for (start = end = 0; str[end]; end++)
 210                         if (isspace(str[end]) || isalnum(str[end]))
 211                                 str[start++] = str[end];
 212                 str[start] = '\0';
 213         }
 214         /* Handle -i */
 215         if (flags & FLAG_i) {
 216                 for (start = end = 0; str[end]; end++)
 217                         if (isprint_asciionly(str[end]))
 218                                 str[start++] = str[end];
 219                 str[start] = '\0';
 220         }
 221         /* Handle -f */
 222         if (flags & FLAG_f)
 223                 for (i = 0; str[i]; i++)
 224                         str[i] = toupper(str[i]);
 225
 226         return str;
 227 }
 228
 229 static struct sort_key *add_key(void)
 230 {
 231         struct sort_key **pkey = &key_list;
 232         while (*pkey)
 233                 pkey = &((*pkey)->next_key);
 234         return *pkey = xzalloc(sizeof(struct sort_key));
 235 }
 236
 237 #define GET_LINE(fp) \
 238         ((option_mask32 & FLAG_z) \
 239         ? bb_get_chunk_from_file(fp, NULL) \
 240         : xmalloc_fgetline(fp))
 241 #else
 242 #define GET_LINE(fp) xmalloc_fgetline(fp)
 243 #endif
 244
 245 /* Iterate through keys list and perform comparisons */
 246 static int compare_keys(const void *xarg, const void *yarg)
 247 {
 248         int flags = option_mask32, retval = 0;
 249         char *x, *y;
 250
 251 #if ENABLE_FEATURE_SORT_BIG
 252         struct sort_key *key;
 253
 254         for (key = key_list; !retval && key; key = key->next_key) {
 255                 flags = key->flags ? key->flags : option_mask32;
 256                 /* Chop out and modify key chunks, handling -dfib */
 257                 x = get_key(*(char **)xarg, key, flags);
 258                 y = get_key(*(char **)yarg, key, flags);
 259 #else
 260         /* This curly bracket serves no purpose but to match the nesting
 261          * level of the for () loop we're not using */
 262         {
 263                 x = *(char **)xarg;
 264                 y = *(char **)yarg;
 265 #endif
 266                 /* Perform actual comparison */
 267                 switch (flags & (FLAG_n | FLAG_M | FLAG_g)) {
 268                 default:
 269                         bb_error_msg_and_die("unknown sort type");
 270                         break;
 271                 /* Ascii sort */
 272                 case 0:
 273 #if ENABLE_LOCALE_SUPPORT
 274                         retval = strcoll(x, y);
 275 #else
 276                         retval = strcmp(x, y);
 277 #endif
 278                         break;
 279 #if ENABLE_FEATURE_SORT_BIG
 280                 case FLAG_g: {
 281                         char *xx, *yy;
 282                         double dx = strtod(x, &xx);
 283                         double dy = strtod(y, &yy);
 284                         /* not numbers < NaN < -infinity < numbers < +infinity) */
 285                         if (x == xx)
 286                                 retval = (y == yy ? 0 : -1);
 287                         else if (y == yy)
 288                                 retval = 1;
 289                         /* Check for isnan */
 290                         else if (dx != dx)
 291                                 retval = (dy != dy) ? 0 : -1;
 292                         else if (dy != dy)
 293                                 retval = 1;
 294                         /* Check for infinity.  Could underflow, but it avoids libm. */
 295                         else if (1.0 / dx == 0.0) {
 296                                 if (dx < 0)
 297                                         retval = (1.0 / dy == 0.0 && dy < 0) ? 0 : -1;
 298                                 else
 299                                         retval = (1.0 / dy == 0.0 && dy > 0) ? 0 : 1;
 300                         } else if (1.0 / dy == 0.0)
 301                                 retval = (dy < 0) ? 1 : -1;
 302                         else
 303                                 retval = (dx > dy) ? 1 : ((dx < dy) ? -1 : 0);
 304                         break;
 305                 }
 306                 case FLAG_M: {
 307                         struct tm thyme;
 308                         int dx;
 309                         char *xx, *yy;
 310
 311                         xx = strptime(x, "%b", &thyme);
 312                         dx = thyme.tm_mon;
 313                         yy = strptime(y, "%b", &thyme);
 314                         if (!xx)
 315                                 retval = (!yy) ? 0 : -1;
 316                         else if (!yy)
 317                                 retval = 1;
 318                         else
 319                                 retval = dx - thyme.tm_mon;
 320                         break;
 321                 }
 322                 /* Full floating point version of -n */
 323                 case FLAG_n: {
 324                         double dx = atof(x);
 325                         double dy = atof(y);
 326                         retval = (dx > dy) ? 1 : ((dx < dy) ? -1 : 0);
 327                         break;
 328                 }
 329                 } /* switch */
 330                 /* Free key copies. */
 331                 if (x != *(char **)xarg) free(x);
 332                 if (y != *(char **)yarg) free(y);
 333                 /* if (retval) break; - done by for () anyway */
 334 #else
 335                 /* Integer version of -n for tiny systems */
 336                 case FLAG_n:
 337                         retval = atoi(x) - atoi(y);
 338                         break;
 339                 } /* switch */
 340 #endif
 341         } /* for */
 342
 343         /* Perform fallback sort if necessary */
 344         if (!retval && !(option_mask32 & FLAG_s)) {
 345                 flags = option_mask32;
 346                 retval = strcmp(*(char **)xarg, *(char **)yarg);
 347         }
 348
 349         if (flags & FLAG_r)
 350                 return -retval;
 351
 352         return retval;
 353 }
 354
 355 #if ENABLE_FEATURE_SORT_BIG
 356 static unsigned str2u(char **str)
 357 {
 358         unsigned long lu;
 359         if (!isdigit((*str)[0]))
 360                 bb_error_msg_and_die("bad field specification");
 361         lu = strtoul(*str, str, 10);
 362         if ((sizeof(long) > sizeof(int) && lu > INT_MAX) || !lu)
 363                 bb_error_msg_and_die("bad field specification");
 364         return lu;
 365 }
 366 #endif
 367
 368 int sort_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
 369 int sort_main(int argc UNUSED_PARAM, char **argv)
 370 {
 371         char *line, **lines;
 372         char *str_ignored, *str_o, *str_t;
 373         llist_t *lst_k = NULL;
 374         int i;
 375         int linecount;
 376         unsigned opts;
 377
 378         xfunc_error_retval = 2;
 379
 380         /* Parse command line options */
 381         /* -o and -t can be given at most once */
 382         opt_complementary = "o--o:t--t"; /* -t, -o: at most one of each */
 383         opts = getopt32(argv, OPT_STR, &str_ignored, &str_ignored, &str_o, &lst_k, &str_t);
 384         /* global b strips leading and trailing spaces */
 385         if (opts & FLAG_b)
 386                 option_mask32 |= FLAG_bb;
 387 #if ENABLE_FEATURE_SORT_BIG
 388         if (opts & FLAG_t) {
 389                 if (!str_t[0] || str_t[1])
 390                         bb_error_msg_and_die("bad -t parameter");
 391                 key_separator = str_t[0];
 392         }
 393         /* note: below this point we use option_mask32, not opts,
 394          * since that reduces register pressure and makes code smaller */
 395
 396         /* Parse sort key */
 397         while (lst_k) {
 398                 enum {
 399                         FLAG_allowed_for_k =
 400                                 FLAG_n | /* Numeric sort */
 401                                 FLAG_g | /* Sort using strtod() */
 402                                 FLAG_M | /* Sort date */
 403                                 FLAG_b | /* Ignore leading blanks */
 404                                 FLAG_r | /* Reverse */
 405                                 FLAG_d | /* Ignore !(isalnum()|isspace()) */
 406                                 FLAG_f | /* Force uppercase */
 407                                 FLAG_i | /* Ignore !isprint() */
 408                         0
 409                 };
 410                 struct sort_key *key = add_key();
 411                 char *str_k = llist_pop(&lst_k);
 412
 413                 i = 0; /* i==0 before comma, 1 after (-k3,6) */
 414                 while (*str_k) {
 415                         /* Start of range */
 416                         /* Cannot use bb_strtou - suffix can be a letter */
 417                         key->range[2*i] = str2u(&str_k);
 418                         if (*str_k == '.') {
 419                                 str_k++;
 420                                 key->range[2*i+1] = str2u(&str_k);
 421                         }
 422                         while (*str_k) {
 423                                 int flag;
 424                                 const char *idx;
 425
 426                                 if (*str_k == ',' && !i++) {
 427                                         str_k++;
 428                                         break;
 429                                 } /* no else needed: fall through to syntax error
 430                                         because comma isn't in OPT_STR */
 431                                 idx = strchr(OPT_STR, *str_k);
 432                                 if (!idx)
 433                                         bb_error_msg_and_die("unknown key option");
 434                                 flag = 1 << (idx - OPT_STR);
 435                                 if (flag & ~FLAG_allowed_for_k)
 436                                         bb_error_msg_and_die("unknown sort type");
 437                                 /* b after ',' means strip _trailing_ space */
 438                                 if (i && flag == FLAG_b)
 439                                         flag = FLAG_bb;
 440                                 key->flags |= flag;
 441                                 str_k++;
 442                         }
 443                 }
 444         }
 445 #endif
 446
 447         /* Open input files and read data */
 448         argv += optind;
 449         if (!*argv)
 450                 *--argv = (char*)"-";
 451         linecount = 0;
 452         lines = NULL;
 453         do {
 454                 /* coreutils 6.9 compat: abort on first open error,
 455                  * do not continue to next file: */
 456                 FILE *fp = xfopen_stdin(*argv);
 457                 for (;;) {
 458                         line = GET_LINE(fp);
 459                         if (!line)
 460                                 break;
 461                         lines = xrealloc_vector(lines, 6, linecount);
 462                         lines[linecount++] = line;
 463                 }
 464                 fclose_if_not_stdin(fp);
 465         } while (*++argv);
 466
 467 #if ENABLE_FEATURE_SORT_BIG
 468         /* If no key, perform alphabetic sort */
 469         if (!key_list)
 470                 add_key()->range[0] = 1;
 471         /* Handle -c */
 472         if (option_mask32 & FLAG_c) {
 473                 int j = (option_mask32 & FLAG_u) ? -1 : 0;
 474                 for (i = 1; i < linecount; i++) {
 475                         if (compare_keys(&lines[i-1], &lines[i]) > j) {
 476                                 fprintf(stderr, "Check line %u\n", i);
 477                                 return EXIT_FAILURE;
 478                         }
 479                 }
 480                 return EXIT_SUCCESS;
 481         }
 482 #endif
 483         /* Perform the actual sort */
 484         qsort(lines, linecount, sizeof(lines[0]), compare_keys);
 485
 486         /* Handle -u */
 487         if (option_mask32 & FLAG_u) {
 488                 int j = 0;
 489                 /* coreutils 6.3 drop lines for which only key is the same */
 490                 /* -- disabling last-resort compare... */
 491                 option_mask32 |= FLAG_s;
 492                 for (i = 1; i < linecount; i++) {
 493                         if (compare_keys(&lines[j], &lines[i]) == 0)
 494                                 free(lines[i]);
 495                         else
 496                                 lines[++j] = lines[i];
 497                 }
 498                 if (linecount)
 499                         linecount = j+1;
 500         }
 501
 502         /* Print it */
 503 #if ENABLE_FEATURE_SORT_BIG
 504         /* Open output file _after_ we read all input ones */
 505         if (option_mask32 & FLAG_o)
 506                 xmove_fd(xopen(str_o, O_WRONLY|O_CREAT|O_TRUNC), STDOUT_FILENO);
 507 #endif
 508         {
 509                 int ch = (option_mask32 & FLAG_z) ? '\0' : '\n';
 510                 for (i = 0; i < linecount; i++)
 511                         printf("%s%c", lines[i], ch);
 512         }
 513
 514         fflush_stdout_and_exit(EXIT_SUCCESS);
 515 }