xref: /freebsd/usr.bin/sort/file.c (revision 0afa8e065e14bb8fd338d75690e0238c00167d40)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (C) 2009 Gabor Kovesdan <gabor@FreeBSD.org>
5  * Copyright (C) 2012 Oleg Moskalenko <mom040267@gmail.com>
6  * All rights reserved.
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 AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  */
29 
30 #include <sys/cdefs.h>
31 __FBSDID("$FreeBSD$");
32 
33 #include <sys/mman.h>
34 #include <sys/stat.h>
35 #include <sys/types.h>
36 #include <sys/queue.h>
37 
38 #include <err.h>
39 #include <fcntl.h>
40 #if defined(SORT_THREADS)
41 #include <pthread.h>
42 #endif
43 #include <semaphore.h>
44 #include <stdio.h>
45 #include <stdlib.h>
46 #include <string.h>
47 #include <unistd.h>
48 #include <wchar.h>
49 #include <wctype.h>
50 
51 #include "coll.h"
52 #include "file.h"
53 #include "radixsort.h"
54 
55 unsigned long long free_memory = 1000000;
56 unsigned long long available_free_memory = 1000000;
57 
58 bool use_mmap;
59 
60 const char *tmpdir = "/var/tmp";
61 const char *compress_program;
62 
63 size_t max_open_files = 16;
64 
65 /*
66  * How much space we read from file at once
67  */
68 #define READ_CHUNK (4096)
69 
70 /*
71  * File reader structure
72  */
73 struct file_reader
74 {
75 	struct reader_buffer	 rb;
76 	FILE			*file;
77 	char			*fname;
78 	unsigned char		*buffer;
79 	unsigned char		*mmapaddr;
80 	unsigned char		*mmapptr;
81 	size_t			 bsz;
82 	size_t			 cbsz;
83 	size_t			 mmapsize;
84 	size_t			 strbeg;
85 	int			 fd;
86 	char			 elsymb;
87 };
88 
89 /*
90  * Structure to be used in file merge process.
91  */
92 struct file_header
93 {
94 	struct file_reader		*fr;
95 	struct sort_list_item		*si; /* current top line */
96 	size_t				 file_pos;
97 };
98 
99 /*
100  * List elements of "cleanable" files list.
101  */
102 struct CLEANABLE_FILE
103 {
104 	char				*fn;
105 	LIST_ENTRY(CLEANABLE_FILE)	 files;
106 };
107 
108 /*
109  * List header of "cleanable" files list.
110  */
111 static LIST_HEAD(CLEANABLE_FILES,CLEANABLE_FILE) tmp_files;
112 
113 /*
114  * Semaphore to protect the tmp file list.
115  * We use semaphore here because it is signal-safe, according to POSIX.
116  * And semaphore does not require pthread library.
117  */
118 static sem_t tmp_files_sem;
119 
120 static void mt_sort(struct sort_list *list,
121     int (*sort_func)(void *, size_t, size_t,
122     int (*)(const void *, const void *)), const char* fn);
123 
124 /*
125  * Init tmp files list
126  */
127 void
128 init_tmp_files(void)
129 {
130 
131 	LIST_INIT(&tmp_files);
132 	sem_init(&tmp_files_sem, 0, 1);
133 }
134 
135 /*
136  * Save name of a tmp file for signal cleanup
137  */
138 void
139 tmp_file_atexit(const char *tmp_file)
140 {
141 
142 	if (tmp_file) {
143 		sem_wait(&tmp_files_sem);
144 		struct CLEANABLE_FILE *item =
145 		    sort_malloc(sizeof(struct CLEANABLE_FILE));
146 		item->fn = sort_strdup(tmp_file);
147 		LIST_INSERT_HEAD(&tmp_files, item, files);
148 		sem_post(&tmp_files_sem);
149 	}
150 }
151 
152 /*
153  * Clear tmp files
154  */
155 void
156 clear_tmp_files(void)
157 {
158 	struct CLEANABLE_FILE *item;
159 
160 	sem_wait(&tmp_files_sem);
161 	LIST_FOREACH(item,&tmp_files,files) {
162 		if ((item) && (item->fn))
163 			unlink(item->fn);
164 	}
165 	sem_post(&tmp_files_sem);
166 }
167 
168 /*
169  * Check whether a file is a temporary file
170  */
171 static bool
172 file_is_tmp(const char* fn)
173 {
174 	struct CLEANABLE_FILE *item;
175 	bool ret = false;
176 
177 	if (fn) {
178 		sem_wait(&tmp_files_sem);
179 		LIST_FOREACH(item,&tmp_files,files) {
180 			if ((item) && (item->fn))
181 				if (strcmp(item->fn, fn) == 0) {
182 					ret = true;
183 					break;
184 				}
185 		}
186 		sem_post(&tmp_files_sem);
187 	}
188 
189 	return (ret);
190 }
191 
192 /*
193  * Generate new temporary file name
194  */
195 char *
196 new_tmp_file_name(void)
197 {
198 	static size_t tfcounter = 0;
199 	static const char *fn = ".bsdsort.";
200 	char *ret;
201 	size_t sz;
202 
203 	sz = strlen(tmpdir) + 1 + strlen(fn) + 32 + 1;
204 	ret = sort_malloc(sz);
205 
206 	sprintf(ret, "%s/%s%d.%lu", tmpdir, fn, (int) getpid(), (unsigned long)(tfcounter++));
207 	tmp_file_atexit(ret);
208 	return (ret);
209 }
210 
211 /*
212  * Initialize file list
213  */
214 void
215 file_list_init(struct file_list *fl, bool tmp)
216 {
217 
218 	if (fl) {
219 		fl->count = 0;
220 		fl->sz = 0;
221 		fl->fns = NULL;
222 		fl->tmp = tmp;
223 	}
224 }
225 
226 /*
227  * Add a file name to the list
228  */
229 void
230 file_list_add(struct file_list *fl, const char *fn, bool allocate)
231 {
232 
233 	if (fl && fn) {
234 		if (fl->count >= fl->sz || (fl->fns == NULL)) {
235 			fl->sz = (fl->sz) * 2 + 1;
236 			fl->fns = sort_realloc(fl->fns, fl->sz *
237 			    sizeof(char *));
238 		}
239 		fl->fns[fl->count] = allocate ? sort_strdup(fn) : fn;
240 		fl->count += 1;
241 	}
242 }
243 
244 /*
245  * Populate file list from array of file names
246  */
247 void
248 file_list_populate(struct file_list *fl, int argc, char **argv, bool allocate)
249 {
250 
251 	if (fl && argv) {
252 		int i;
253 
254 		for (i = 0; i < argc; i++)
255 			file_list_add(fl, argv[i], allocate);
256 	}
257 }
258 
259 /*
260  * Clean file list data and delete the files,
261  * if this is a list of temporary files
262  */
263 void
264 file_list_clean(struct file_list *fl)
265 {
266 
267 	if (fl) {
268 		if (fl->fns) {
269 			size_t i;
270 
271 			for (i = 0; i < fl->count; i++) {
272 				if (fl->fns[i]) {
273 					if (fl->tmp)
274 						unlink(fl->fns[i]);
275 					sort_free(fl->fns[i]);
276 					fl->fns[i] = 0;
277 				}
278 			}
279 			sort_free(fl->fns);
280 			fl->fns = NULL;
281 		}
282 		fl->sz = 0;
283 		fl->count = 0;
284 		fl->tmp = false;
285 	}
286 }
287 
288 /*
289  * Init sort list
290  */
291 void
292 sort_list_init(struct sort_list *l)
293 {
294 
295 	if (l) {
296 		l->count = 0;
297 		l->size = 0;
298 		l->memsize = sizeof(struct sort_list);
299 		l->list = NULL;
300 	}
301 }
302 
303 /*
304  * Add string to sort list
305  */
306 void
307 sort_list_add(struct sort_list *l, struct bwstring *str)
308 {
309 
310 	if (l && str) {
311 		size_t indx = l->count;
312 
313 		if ((l->list == NULL) || (indx >= l->size)) {
314 			size_t newsize = (l->size + 1) + 1024;
315 
316 			l->list = sort_realloc(l->list,
317 			    sizeof(struct sort_list_item*) * newsize);
318 			l->memsize += (newsize - l->size) *
319 			    sizeof(struct sort_list_item*);
320 			l->size = newsize;
321 		}
322 		l->list[indx] = sort_list_item_alloc();
323 		sort_list_item_set(l->list[indx], str);
324 		l->memsize += sort_list_item_size(l->list[indx]);
325 		l->count += 1;
326 	}
327 }
328 
329 /*
330  * Clean sort list data
331  */
332 void
333 sort_list_clean(struct sort_list *l)
334 {
335 
336 	if (l) {
337 		if (l->list) {
338 			size_t i;
339 
340 			for (i = 0; i < l->count; i++) {
341 				struct sort_list_item *item;
342 
343 				item = l->list[i];
344 
345 				if (item) {
346 					sort_list_item_clean(item);
347 					sort_free(item);
348 					l->list[i] = NULL;
349 				}
350 			}
351 			sort_free(l->list);
352 			l->list = NULL;
353 		}
354 		l->count = 0;
355 		l->size = 0;
356 		l->memsize = sizeof(struct sort_list);
357 	}
358 }
359 
360 /*
361  * Write sort list to file
362  */
363 void
364 sort_list_dump(struct sort_list *l, const char *fn)
365 {
366 
367 	if (l && fn) {
368 		FILE *f;
369 
370 		f = openfile(fn, "w");
371 		if (f == NULL)
372 			err(2, NULL);
373 
374 		if (l->list) {
375 			size_t i;
376 			if (!(sort_opts_vals.uflag)) {
377 				for (i = 0; i < l->count; ++i)
378 					bwsfwrite(l->list[i]->str, f,
379 					    sort_opts_vals.zflag);
380 			} else {
381 				struct sort_list_item *last_printed_item = NULL;
382 				struct sort_list_item *item;
383 				for (i = 0; i < l->count; ++i) {
384 					item = l->list[i];
385 					if ((last_printed_item == NULL) ||
386 					    list_coll(&last_printed_item, &item)) {
387 						bwsfwrite(item->str, f, sort_opts_vals.zflag);
388 						last_printed_item = item;
389 					}
390 				}
391 			}
392 		}
393 
394 		closefile(f, fn);
395 	}
396 }
397 
398 /*
399  * Checks if the given file is sorted.  Stops at the first disorder,
400  * prints the disordered line and returns 1.
401  */
402 int
403 check(const char *fn)
404 {
405 	struct bwstring *s1, *s2, *s1disorder, *s2disorder;
406 	struct file_reader *fr;
407 	struct keys_array *ka1, *ka2;
408 	int res;
409 	size_t pos, posdisorder;
410 
411 	s1 = s2 = s1disorder = s2disorder = NULL;
412 	ka1 = ka2 = NULL;
413 
414 	fr = file_reader_init(fn);
415 
416 	res = 0;
417 	pos = 1;
418 	posdisorder = 1;
419 
420 	if (fr == NULL) {
421 		err(2, NULL);
422 		goto end;
423 	}
424 
425 	s1 = file_reader_readline(fr);
426 	if (s1 == NULL)
427 		goto end;
428 
429 	ka1 = keys_array_alloc();
430 	preproc(s1, ka1);
431 
432 	s2 = file_reader_readline(fr);
433 	if (s2 == NULL)
434 		goto end;
435 
436 	ka2 = keys_array_alloc();
437 	preproc(s2, ka2);
438 
439 	for (;;) {
440 
441 		if (debug_sort) {
442 			bwsprintf(stdout, s2, "s1=<", ">");
443 			bwsprintf(stdout, s1, "s2=<", ">");
444 		}
445 		int cmp = key_coll(ka2, ka1, 0);
446 		if (debug_sort)
447 			printf("; cmp1=%d", cmp);
448 
449 		if (!cmp && sort_opts_vals.complex_sort &&
450 		    !(sort_opts_vals.uflag) && !(sort_opts_vals.sflag)) {
451 			cmp = top_level_str_coll(s2, s1);
452 			if (debug_sort)
453 				printf("; cmp2=%d", cmp);
454 		}
455 		if (debug_sort)
456 			printf("\n");
457 
458 		if ((sort_opts_vals.uflag && (cmp <= 0)) || (cmp < 0)) {
459 			if (!(sort_opts_vals.csilentflag)) {
460 				s2disorder = bwsdup(s2);
461 				posdisorder = pos;
462 				if (debug_sort)
463 					s1disorder = bwsdup(s1);
464 			}
465 			res = 1;
466 			goto end;
467 		}
468 
469 		pos++;
470 
471 		clean_keys_array(s1, ka1);
472 		sort_free(ka1);
473 		ka1 = ka2;
474 		ka2 = NULL;
475 
476 		bwsfree(s1);
477 		s1 = s2;
478 
479 		s2 = file_reader_readline(fr);
480 		if (s2 == NULL)
481 			goto end;
482 
483 		ka2 = keys_array_alloc();
484 		preproc(s2, ka2);
485 	}
486 
487 end:
488 	if (ka1) {
489 		clean_keys_array(s1, ka1);
490 		sort_free(ka1);
491 	}
492 
493 	if (s1)
494 		bwsfree(s1);
495 
496 	if (ka2) {
497 		clean_keys_array(s2, ka2);
498 		sort_free(ka2);
499 	}
500 
501 	if (s2)
502 		bwsfree(s2);
503 
504 	if ((fn == NULL) || (*fn == 0) || (strcmp(fn, "-") == 0)) {
505 		for (;;) {
506 			s2 = file_reader_readline(fr);
507 			if (s2 == NULL)
508 				break;
509 			bwsfree(s2);
510 		}
511 	}
512 
513 	file_reader_free(fr);
514 
515 	if (s2disorder) {
516 		bws_disorder_warnx(s2disorder, fn, posdisorder);
517 		if (s1disorder) {
518 			bws_disorder_warnx(s1disorder, fn, posdisorder);
519 			if (s1disorder != s2disorder)
520 				bwsfree(s1disorder);
521 		}
522 		bwsfree(s2disorder);
523 		s1disorder = NULL;
524 		s2disorder = NULL;
525 	}
526 
527 	if (res)
528 		exit(res);
529 
530 	return (0);
531 }
532 
533 /*
534  * Opens a file.  If the given filename is "-", stdout will be
535  * opened.
536  */
537 FILE *
538 openfile(const char *fn, const char *mode)
539 {
540 	FILE *file;
541 
542 	if (strcmp(fn, "-") == 0) {
543 		return ((mode && mode[0] == 'r') ? stdin : stdout);
544 	} else {
545 		mode_t orig_file_mask = 0;
546 		int is_tmp = file_is_tmp(fn);
547 
548 		if (is_tmp && (mode[0] == 'w'))
549 			orig_file_mask = umask(S_IWGRP | S_IWOTH |
550 			    S_IRGRP | S_IROTH);
551 
552 		if (is_tmp && (compress_program != NULL)) {
553 			char *cmd;
554 			size_t cmdsz;
555 
556 			cmdsz = strlen(fn) + 128;
557 			cmd = sort_malloc(cmdsz);
558 
559 			fflush(stdout);
560 
561 			if (mode[0] == 'r')
562 				snprintf(cmd, cmdsz - 1, "cat %s | %s -d",
563 				    fn, compress_program);
564 			else if (mode[0] == 'w')
565 				snprintf(cmd, cmdsz - 1, "%s > %s",
566 				    compress_program, fn);
567 			else
568 				err(2, "%s", getstr(7));
569 
570 			if ((file = popen(cmd, mode)) == NULL)
571 				err(2, NULL);
572 
573 			sort_free(cmd);
574 
575 		} else
576 			if ((file = fopen(fn, mode)) == NULL)
577 				err(2, NULL);
578 
579 		if (is_tmp && (mode[0] == 'w'))
580 			umask(orig_file_mask);
581 	}
582 
583 	return (file);
584 }
585 
586 /*
587  * Close file
588  */
589 void
590 closefile(FILE *f, const char *fn)
591 {
592 	if (f == NULL) {
593 		;
594 	} else if (f == stdin) {
595 		;
596 	} else if (f == stdout) {
597 		fflush(f);
598 	} else {
599 		if (file_is_tmp(fn) && compress_program != NULL) {
600 			if(pclose(f)<0)
601 				err(2,NULL);
602 		} else
603 			fclose(f);
604 	}
605 }
606 
607 /*
608  * Reads a file into the internal buffer.
609  */
610 struct file_reader *
611 file_reader_init(const char *fsrc)
612 {
613 	struct file_reader *ret;
614 
615 	if (fsrc == NULL)
616 		fsrc = "-";
617 
618 	ret = sort_malloc(sizeof(struct file_reader));
619 	memset(ret, 0, sizeof(struct file_reader));
620 
621 	ret->elsymb = '\n';
622 	if (sort_opts_vals.zflag)
623 		ret->elsymb = 0;
624 
625 	ret->fname = sort_strdup(fsrc);
626 
627 	if (strcmp(fsrc, "-") && (compress_program == NULL) && use_mmap) {
628 
629 		do {
630 			struct stat stat_buf;
631 			void *addr;
632 			size_t sz = 0;
633 			int fd, flags;
634 
635 			flags = MAP_NOCORE | MAP_NOSYNC;
636 
637 			fd = open(fsrc, O_RDONLY);
638 			if (fd < 0)
639 				err(2, NULL);
640 
641 			if (fstat(fd, &stat_buf) < 0) {
642 				close(fd);
643 				break;
644 			}
645 
646 			sz = stat_buf.st_size;
647 
648 #if defined(MAP_PREFAULT_READ)
649 			flags |= MAP_PREFAULT_READ;
650 #endif
651 
652 			addr = mmap(NULL, sz, PROT_READ, flags, fd, 0);
653 			if (addr == MAP_FAILED) {
654 				close(fd);
655 				break;
656 			}
657 
658 			ret->fd = fd;
659 			ret->mmapaddr = addr;
660 			ret->mmapsize = sz;
661 			ret->mmapptr = ret->mmapaddr;
662 
663 		} while (0);
664 	}
665 
666 	if (ret->mmapaddr == NULL) {
667 		ret->file = openfile(fsrc, "r");
668 		if (ret->file == NULL)
669 			err(2, NULL);
670 
671 		if (strcmp(fsrc, "-")) {
672 			ret->cbsz = READ_CHUNK;
673 			ret->buffer = sort_malloc(ret->cbsz);
674 			ret->bsz = 0;
675 			ret->strbeg = 0;
676 
677 			ret->bsz = fread(ret->buffer, 1, ret->cbsz, ret->file);
678 			if (ret->bsz == 0) {
679 				if (ferror(ret->file))
680 					err(2, NULL);
681 			}
682 		}
683 	}
684 
685 	return (ret);
686 }
687 
688 struct bwstring *
689 file_reader_readline(struct file_reader *fr)
690 {
691 	struct bwstring *ret = NULL;
692 
693 	if (fr->mmapaddr) {
694 		unsigned char *mmapend;
695 
696 		mmapend = fr->mmapaddr + fr->mmapsize;
697 		if (fr->mmapptr >= mmapend)
698 			return (NULL);
699 		else {
700 			unsigned char *strend;
701 			size_t sz;
702 
703 			sz = mmapend - fr->mmapptr;
704 			strend = memchr(fr->mmapptr, fr->elsymb, sz);
705 
706 			if (strend == NULL) {
707 				ret = bwscsbdup(fr->mmapptr, sz);
708 				fr->mmapptr = mmapend;
709 			} else {
710 				ret = bwscsbdup(fr->mmapptr, strend -
711 				    fr->mmapptr);
712 				fr->mmapptr = strend + 1;
713 			}
714 		}
715 
716 	} else if (fr->file != stdin) {
717 		unsigned char *strend;
718 		size_t bsz1, remsz, search_start;
719 
720 		search_start = 0;
721 		remsz = 0;
722 		strend = NULL;
723 
724 		if (fr->bsz > fr->strbeg)
725 			remsz = fr->bsz - fr->strbeg;
726 
727 		/* line read cycle */
728 		for (;;) {
729 			if (remsz > search_start)
730 				strend = memchr(fr->buffer + fr->strbeg +
731 				    search_start, fr->elsymb, remsz -
732 				    search_start);
733 			else
734 				strend = NULL;
735 
736 			if (strend)
737 				break;
738 			if (feof(fr->file))
739 				break;
740 
741 			if (fr->bsz != fr->cbsz)
742 				/* NOTREACHED */
743 				err(2, "File read software error 1");
744 
745 			if (remsz > (READ_CHUNK >> 1)) {
746 				search_start = fr->cbsz - fr->strbeg;
747 				fr->cbsz += READ_CHUNK;
748 				fr->buffer = sort_realloc(fr->buffer,
749 				    fr->cbsz);
750 				bsz1 = fread(fr->buffer + fr->bsz, 1,
751 				    READ_CHUNK, fr->file);
752 				if (bsz1 == 0) {
753 					if (ferror(fr->file))
754 						err(2, NULL);
755 					break;
756 				}
757 				fr->bsz += bsz1;
758 				remsz += bsz1;
759 			} else {
760 				if (remsz > 0 && fr->strbeg>0)
761 					bcopy(fr->buffer + fr->strbeg,
762 					    fr->buffer, remsz);
763 
764 				fr->strbeg = 0;
765 				search_start = remsz;
766 				bsz1 = fread(fr->buffer + remsz, 1,
767 				    fr->cbsz - remsz, fr->file);
768 				if (bsz1 == 0) {
769 					if (ferror(fr->file))
770 						err(2, NULL);
771 					break;
772 				}
773 				fr->bsz = remsz + bsz1;
774 				remsz = fr->bsz;
775 			}
776 		}
777 
778 		if (strend == NULL)
779 			strend = fr->buffer + fr->bsz;
780 
781 		if ((fr->buffer + fr->strbeg <= strend) &&
782 		    (fr->strbeg < fr->bsz) && (remsz>0))
783 			ret = bwscsbdup(fr->buffer + fr->strbeg, strend -
784 			    fr->buffer - fr->strbeg);
785 
786 		fr->strbeg = (strend - fr->buffer) + 1;
787 
788 	} else {
789 		size_t len = 0;
790 
791 		ret = bwsfgetln(fr->file, &len, sort_opts_vals.zflag,
792 		    &(fr->rb));
793 	}
794 
795 	return (ret);
796 }
797 
798 static void
799 file_reader_clean(struct file_reader *fr)
800 {
801 
802 	if (fr) {
803 		if (fr->mmapaddr)
804 			munmap(fr->mmapaddr, fr->mmapsize);
805 
806 		if (fr->fd)
807 			close(fr->fd);
808 
809 		if (fr->buffer)
810 			sort_free(fr->buffer);
811 
812 		if (fr->file)
813 			if (fr->file != stdin)
814 				closefile(fr->file, fr->fname);
815 
816 		if(fr->fname)
817 			sort_free(fr->fname);
818 
819 		memset(fr, 0, sizeof(struct file_reader));
820 	}
821 }
822 
823 void
824 file_reader_free(struct file_reader *fr)
825 {
826 
827 	if (fr) {
828 		file_reader_clean(fr);
829 		sort_free(fr);
830 	}
831 }
832 
833 int
834 procfile(const char *fsrc, struct sort_list *list, struct file_list *fl)
835 {
836 	struct file_reader *fr;
837 
838 	fr = file_reader_init(fsrc);
839 	if (fr == NULL)
840 		err(2, NULL);
841 
842 	/* file browse cycle */
843 	for (;;) {
844 		struct bwstring *bws;
845 
846 		bws = file_reader_readline(fr);
847 
848 		if (bws == NULL)
849 			break;
850 
851 		sort_list_add(list, bws);
852 
853 		if (list->memsize >= available_free_memory) {
854 			char *fn;
855 
856 			fn = new_tmp_file_name();
857 			sort_list_to_file(list, fn);
858 			file_list_add(fl, fn, false);
859 			sort_list_clean(list);
860 		}
861 	}
862 
863 	file_reader_free(fr);
864 
865 	return (0);
866 }
867 
868 /*
869  * Compare file headers. Files with EOF always go to the end of the list.
870  */
871 static int
872 file_header_cmp(struct file_header *f1, struct file_header *f2)
873 {
874 
875 	if (f1 == f2)
876 		return (0);
877 	else {
878 		if (f1->fr == NULL) {
879 			return ((f2->fr == NULL) ? 0 : +1);
880 		} else if (f2->fr == NULL)
881 			return (-1);
882 		else {
883 			int ret;
884 
885 			ret = list_coll(&(f1->si), &(f2->si));
886 			if (!ret)
887 				return ((f1->file_pos < f2->file_pos) ? -1 : +1);
888 			return (ret);
889 		}
890 	}
891 }
892 
893 /*
894  * Allocate and init file header structure
895  */
896 static void
897 file_header_init(struct file_header **fh, const char *fn, size_t file_pos)
898 {
899 
900 	if (fh && fn) {
901 		struct bwstring *line;
902 
903 		*fh = sort_malloc(sizeof(struct file_header));
904 		(*fh)->file_pos = file_pos;
905 		(*fh)->fr = file_reader_init(fn);
906 		if ((*fh)->fr == NULL) {
907 			perror(fn);
908 			err(2, "%s", getstr(8));
909 		}
910 		line = file_reader_readline((*fh)->fr);
911 		if (line == NULL) {
912 			file_reader_free((*fh)->fr);
913 			(*fh)->fr = NULL;
914 			(*fh)->si = NULL;
915 		} else {
916 			(*fh)->si = sort_list_item_alloc();
917 			sort_list_item_set((*fh)->si, line);
918 		}
919 	}
920 }
921 
922 /*
923  * Close file
924  */
925 static void
926 file_header_close(struct file_header **fh)
927 {
928 
929 	if (fh && *fh) {
930 		if ((*fh)->fr) {
931 			file_reader_free((*fh)->fr);
932 			(*fh)->fr = NULL;
933 		}
934 		if ((*fh)->si) {
935 			sort_list_item_clean((*fh)->si);
936 			sort_free((*fh)->si);
937 			(*fh)->si = NULL;
938 		}
939 		sort_free(*fh);
940 		*fh = NULL;
941 	}
942 }
943 
944 /*
945  * Swap two array elements
946  */
947 static void
948 file_header_swap(struct file_header **fh, size_t i1, size_t i2)
949 {
950 	struct file_header *tmp;
951 
952 	tmp = fh[i1];
953 	fh[i1] = fh[i2];
954 	fh[i2] = tmp;
955 }
956 
957 /* heap algorithm ==>> */
958 
959 /*
960  * See heap sort algorithm
961  * "Raises" last element to its right place
962  */
963 static void
964 file_header_heap_swim(struct file_header **fh, size_t indx)
965 {
966 
967 	if (indx > 0) {
968 		size_t parent_index;
969 
970 		parent_index = (indx - 1) >> 1;
971 
972 		if (file_header_cmp(fh[indx], fh[parent_index]) < 0) {
973 			/* swap child and parent and continue */
974 			file_header_swap(fh, indx, parent_index);
975 			file_header_heap_swim(fh, parent_index);
976 		}
977 	}
978 }
979 
980 /*
981  * Sink the top element to its correct position
982  */
983 static void
984 file_header_heap_sink(struct file_header **fh, size_t indx, size_t size)
985 {
986 	size_t left_child_index;
987 	size_t right_child_index;
988 
989 	left_child_index = indx + indx + 1;
990 	right_child_index = left_child_index + 1;
991 
992 	if (left_child_index < size) {
993 		size_t min_child_index;
994 
995 		min_child_index = left_child_index;
996 
997 		if ((right_child_index < size) &&
998 		    (file_header_cmp(fh[left_child_index],
999 		    fh[right_child_index]) > 0))
1000 			min_child_index = right_child_index;
1001 		if (file_header_cmp(fh[indx], fh[min_child_index]) > 0) {
1002 			file_header_swap(fh, indx, min_child_index);
1003 			file_header_heap_sink(fh, min_child_index, size);
1004 		}
1005 	}
1006 }
1007 
1008 /* <<== heap algorithm */
1009 
1010 /*
1011  * Adds element to the "left" end
1012  */
1013 static void
1014 file_header_list_rearrange_from_header(struct file_header **fh, size_t size)
1015 {
1016 
1017 	file_header_heap_sink(fh, 0, size);
1018 }
1019 
1020 /*
1021  * Adds element to the "right" end
1022  */
1023 static void
1024 file_header_list_push(struct file_header *f, struct file_header **fh, size_t size)
1025 {
1026 
1027 	fh[size++] = f;
1028 	file_header_heap_swim(fh, size - 1);
1029 }
1030 
1031 struct last_printed
1032 {
1033 	struct bwstring *str;
1034 };
1035 
1036 /*
1037  * Prints the current line of the file
1038  */
1039 static void
1040 file_header_print(struct file_header *fh, FILE *f_out, struct last_printed *lp)
1041 {
1042 
1043 	if (fh && fh->fr && f_out && fh->si && fh->si->str) {
1044 		if (sort_opts_vals.uflag) {
1045 			if ((lp->str == NULL) || (str_list_coll(lp->str, &(fh->si)))) {
1046 				bwsfwrite(fh->si->str, f_out, sort_opts_vals.zflag);
1047 				if (lp->str)
1048 					bwsfree(lp->str);
1049 				lp->str = bwsdup(fh->si->str);
1050 			}
1051 		} else
1052 			bwsfwrite(fh->si->str, f_out, sort_opts_vals.zflag);
1053 	}
1054 }
1055 
1056 /*
1057  * Read next line
1058  */
1059 static void
1060 file_header_read_next(struct file_header *fh)
1061 {
1062 
1063 	if (fh && fh->fr) {
1064 		struct bwstring *tmp;
1065 
1066 		tmp = file_reader_readline(fh->fr);
1067 		if (tmp == NULL) {
1068 			file_reader_free(fh->fr);
1069 			fh->fr = NULL;
1070 			if (fh->si) {
1071 				sort_list_item_clean(fh->si);
1072 				sort_free(fh->si);
1073 				fh->si = NULL;
1074 			}
1075 		} else {
1076 			if (fh->si == NULL)
1077 				fh->si = sort_list_item_alloc();
1078 			sort_list_item_set(fh->si, tmp);
1079 		}
1080 	}
1081 }
1082 
1083 /*
1084  * Merge array of "files headers"
1085  */
1086 static void
1087 file_headers_merge(size_t fnum, struct file_header **fh, FILE *f_out)
1088 {
1089 	struct last_printed lp;
1090 	size_t i;
1091 
1092 	memset(&lp, 0, sizeof(lp));
1093 
1094 	/*
1095 	 * construct the initial sort structure
1096 	 */
1097 	for (i = 0; i < fnum; i++)
1098 		file_header_list_push(fh[i], fh, i);
1099 
1100 	while (fh[0]->fr) { /* unfinished files are always in front */
1101 		/* output the smallest line: */
1102 		file_header_print(fh[0], f_out, &lp);
1103 		/* read a new line, if possible: */
1104 		file_header_read_next(fh[0]);
1105 		/* re-arrange the list: */
1106 		file_header_list_rearrange_from_header(fh, fnum);
1107 	}
1108 
1109 	if (lp.str)
1110 		bwsfree(lp.str);
1111 }
1112 
1113 /*
1114  * Merges the given files into the output file, which can be
1115  * stdout.
1116  */
1117 static void
1118 merge_files_array(size_t argc, const char **argv, const char *fn_out)
1119 {
1120 
1121 	if (argv && fn_out) {
1122 		struct file_header **fh;
1123 		FILE *f_out;
1124 		size_t i;
1125 
1126 		f_out = openfile(fn_out, "w");
1127 
1128 		if (f_out == NULL)
1129 			err(2, NULL);
1130 
1131 		fh = sort_malloc((argc + 1) * sizeof(struct file_header *));
1132 
1133 		for (i = 0; i < argc; i++)
1134 			file_header_init(fh + i, argv[i], (size_t) i);
1135 
1136 		file_headers_merge(argc, fh, f_out);
1137 
1138 		for (i = 0; i < argc; i++)
1139 			file_header_close(fh + i);
1140 
1141 		sort_free(fh);
1142 
1143 		closefile(f_out, fn_out);
1144 	}
1145 }
1146 
1147 /*
1148  * Shrinks the file list until its size smaller than max number of opened files
1149  */
1150 static int
1151 shrink_file_list(struct file_list *fl)
1152 {
1153 
1154 	if ((fl == NULL) || (size_t) (fl->count) < max_open_files)
1155 		return (0);
1156 	else {
1157 		struct file_list new_fl;
1158 		size_t indx = 0;
1159 
1160 		file_list_init(&new_fl, true);
1161 		while (indx < fl->count) {
1162 			char *fnew;
1163 			size_t num;
1164 
1165 			num = fl->count - indx;
1166 			fnew = new_tmp_file_name();
1167 
1168 			if ((size_t) num >= max_open_files)
1169 				num = max_open_files - 1;
1170 			merge_files_array(num, fl->fns + indx, fnew);
1171 			if (fl->tmp) {
1172 				size_t i;
1173 
1174 				for (i = 0; i < num; i++)
1175 					unlink(fl->fns[indx + i]);
1176 			}
1177 			file_list_add(&new_fl, fnew, false);
1178 			indx += num;
1179 		}
1180 		fl->tmp = false; /* already taken care of */
1181 		file_list_clean(fl);
1182 
1183 		fl->count = new_fl.count;
1184 		fl->fns = new_fl.fns;
1185 		fl->sz = new_fl.sz;
1186 		fl->tmp = new_fl.tmp;
1187 
1188 		return (1);
1189 	}
1190 }
1191 
1192 /*
1193  * Merge list of files
1194  */
1195 void
1196 merge_files(struct file_list *fl, const char *fn_out)
1197 {
1198 
1199 	if (fl && fn_out) {
1200 		while (shrink_file_list(fl));
1201 
1202 		merge_files_array(fl->count, fl->fns, fn_out);
1203 	}
1204 }
1205 
1206 static const char *
1207 get_sort_method_name(int sm)
1208 {
1209 
1210 	if (sm == SORT_MERGESORT)
1211 		return "mergesort";
1212 	else if (sort_opts_vals.sort_method == SORT_RADIXSORT)
1213 		return "radixsort";
1214 	else if (sort_opts_vals.sort_method == SORT_HEAPSORT)
1215 		return "heapsort";
1216 	else
1217 		return "quicksort";
1218 }
1219 
1220 /*
1221  * Wrapper for qsort
1222  */
1223 static int sort_qsort(void *list, size_t count, size_t elem_size,
1224     int (*cmp_func)(const void *, const void *))
1225 {
1226 
1227 	qsort(list, count, elem_size, cmp_func);
1228 	return (0);
1229 }
1230 
1231 /*
1232  * Sort list of lines and writes it to the file
1233  */
1234 void
1235 sort_list_to_file(struct sort_list *list, const char *outfile)
1236 {
1237 	struct sort_mods *sm = &(keys[0].sm);
1238 
1239 	if (!(sm->Mflag) && !(sm->Rflag) && !(sm->Vflag) &&
1240 	    !(sm->gflag) && !(sm->hflag) && !(sm->nflag)) {
1241 		if ((sort_opts_vals.sort_method == SORT_DEFAULT) && byte_sort)
1242 			sort_opts_vals.sort_method = SORT_RADIXSORT;
1243 
1244 	} else if (sort_opts_vals.sort_method == SORT_RADIXSORT)
1245 		err(2, "%s", getstr(9));
1246 
1247 	/*
1248 	 * to handle stable sort and the unique cases in the
1249 	 * right order, we need stable basic algorithm
1250 	 */
1251 	if (sort_opts_vals.sflag) {
1252 		switch (sort_opts_vals.sort_method){
1253 		case SORT_MERGESORT:
1254 			break;
1255 		case SORT_RADIXSORT:
1256 			break;
1257 		case SORT_DEFAULT:
1258 			sort_opts_vals.sort_method = SORT_MERGESORT;
1259 			break;
1260 		default:
1261 			errx(2, "%s", getstr(10));
1262 		}
1263 	}
1264 
1265 	if (sort_opts_vals.sort_method == SORT_DEFAULT)
1266 		sort_opts_vals.sort_method = DEFAULT_SORT_ALGORITHM;
1267 
1268 	if (debug_sort)
1269 		printf("sort_method=%s\n",
1270 		    get_sort_method_name(sort_opts_vals.sort_method));
1271 
1272 	switch (sort_opts_vals.sort_method){
1273 	case SORT_RADIXSORT:
1274 		rxsort(list->list, list->count);
1275 		sort_list_dump(list, outfile);
1276 		break;
1277 	case SORT_MERGESORT:
1278 		mt_sort(list, mergesort, outfile);
1279 		break;
1280 	case SORT_HEAPSORT:
1281 		mt_sort(list, heapsort,	outfile);
1282 		break;
1283 	case SORT_QSORT:
1284 		mt_sort(list, sort_qsort, outfile);
1285 		break;
1286 	default:
1287 		mt_sort(list, DEFAULT_SORT_FUNC, outfile);
1288 		break;
1289 	}
1290 }
1291 
1292 /******************* MT SORT ************************/
1293 
1294 #if defined(SORT_THREADS)
1295 /* semaphore to count threads */
1296 static sem_t mtsem;
1297 
1298 /* current system sort function */
1299 static int (*g_sort_func)(void *, size_t, size_t,
1300     int(*)(const void *, const void *));
1301 
1302 /*
1303  * Sort cycle thread (in multi-threaded mode)
1304  */
1305 static void*
1306 mt_sort_thread(void* arg)
1307 {
1308 	struct sort_list *list = arg;
1309 
1310 	g_sort_func(list->list, list->count, sizeof(struct sort_list_item *),
1311 	    (int(*)(const void *, const void *)) list_coll);
1312 
1313 	sem_post(&mtsem);
1314 
1315 	return (arg);
1316 }
1317 
1318 /*
1319  * Compare sub-lists. Empty sub-lists always go to the end of the list.
1320  */
1321 static int
1322 sub_list_cmp(struct sort_list *l1, struct sort_list *l2)
1323 {
1324 
1325 	if (l1 == l2)
1326 		return (0);
1327 	else {
1328 		if (l1->count == 0) {
1329 			return ((l2->count == 0) ? 0 : +1);
1330 		} else if (l2->count == 0) {
1331 			return (-1);
1332 		} else {
1333 			int ret;
1334 
1335 			ret = list_coll(&(l1->list[0]), &(l2->list[0]));
1336 			if (!ret)
1337 				return ((l1->sub_list_pos < l2->sub_list_pos) ?
1338 				    -1 : +1);
1339 			return (ret);
1340 		}
1341 	}
1342 }
1343 
1344 /*
1345  * Swap two array elements
1346  */
1347 static void
1348 sub_list_swap(struct sort_list **sl, size_t i1, size_t i2)
1349 {
1350 	struct sort_list *tmp;
1351 
1352 	tmp = sl[i1];
1353 	sl[i1] = sl[i2];
1354 	sl[i2] = tmp;
1355 }
1356 
1357 /* heap algorithm ==>> */
1358 
1359 /*
1360  * See heap sort algorithm
1361  * "Raises" last element to its right place
1362  */
1363 static void
1364 sub_list_swim(struct sort_list **sl, size_t indx)
1365 {
1366 
1367 	if (indx > 0) {
1368 		size_t parent_index;
1369 
1370 		parent_index = (indx - 1) >> 1;
1371 
1372 		if (sub_list_cmp(sl[indx], sl[parent_index]) < 0) {
1373 			/* swap child and parent and continue */
1374 			sub_list_swap(sl, indx, parent_index);
1375 			sub_list_swim(sl, parent_index);
1376 		}
1377 	}
1378 }
1379 
1380 /*
1381  * Sink the top element to its correct position
1382  */
1383 static void
1384 sub_list_sink(struct sort_list **sl, size_t indx, size_t size)
1385 {
1386 	size_t left_child_index;
1387 	size_t right_child_index;
1388 
1389 	left_child_index = indx + indx + 1;
1390 	right_child_index = left_child_index + 1;
1391 
1392 	if (left_child_index < size) {
1393 		size_t min_child_index;
1394 
1395 		min_child_index = left_child_index;
1396 
1397 		if ((right_child_index < size) &&
1398 		    (sub_list_cmp(sl[left_child_index],
1399 		    sl[right_child_index]) > 0))
1400 			min_child_index = right_child_index;
1401 		if (sub_list_cmp(sl[indx], sl[min_child_index]) > 0) {
1402 			sub_list_swap(sl, indx, min_child_index);
1403 			sub_list_sink(sl, min_child_index, size);
1404 		}
1405 	}
1406 }
1407 
1408 /* <<== heap algorithm */
1409 
1410 /*
1411  * Adds element to the "right" end
1412  */
1413 static void
1414 sub_list_push(struct sort_list *s, struct sort_list **sl, size_t size)
1415 {
1416 
1417 	sl[size++] = s;
1418 	sub_list_swim(sl, size - 1);
1419 }
1420 
1421 struct last_printed_item
1422 {
1423 	struct sort_list_item *item;
1424 };
1425 
1426 /*
1427  * Prints the current line of the file
1428  */
1429 static void
1430 sub_list_header_print(struct sort_list *sl, FILE *f_out,
1431     struct last_printed_item *lp)
1432 {
1433 
1434 	if (sl && sl->count && f_out && sl->list[0]->str) {
1435 		if (sort_opts_vals.uflag) {
1436 			if ((lp->item == NULL) || (list_coll(&(lp->item),
1437 			    &(sl->list[0])))) {
1438 				bwsfwrite(sl->list[0]->str, f_out,
1439 				    sort_opts_vals.zflag);
1440 				lp->item = sl->list[0];
1441 			}
1442 		} else
1443 			bwsfwrite(sl->list[0]->str, f_out,
1444 			    sort_opts_vals.zflag);
1445 	}
1446 }
1447 
1448 /*
1449  * Read next line
1450  */
1451 static void
1452 sub_list_next(struct sort_list *sl)
1453 {
1454 
1455 	if (sl && sl->count) {
1456 		sl->list += 1;
1457 		sl->count -= 1;
1458 	}
1459 }
1460 
1461 /*
1462  * Merge sub-lists to a file
1463  */
1464 static void
1465 merge_sub_lists(struct sort_list **sl, size_t n, FILE* f_out)
1466 {
1467 	struct last_printed_item lp;
1468 	size_t i;
1469 
1470 	memset(&lp,0,sizeof(lp));
1471 
1472 	/* construct the initial list: */
1473 	for (i = 0; i < n; i++)
1474 		sub_list_push(sl[i], sl, i);
1475 
1476 	while (sl[0]->count) { /* unfinished lists are always in front */
1477 		/* output the smallest line: */
1478 		sub_list_header_print(sl[0], f_out, &lp);
1479 		/* move to a new line, if possible: */
1480 		sub_list_next(sl[0]);
1481 		/* re-arrange the list: */
1482 		sub_list_sink(sl, 0, n);
1483 	}
1484 }
1485 
1486 /*
1487  * Merge sub-lists to a file
1488  */
1489 static void
1490 merge_list_parts(struct sort_list **parts, size_t n, const char *fn)
1491 {
1492 	FILE* f_out;
1493 
1494 	f_out = openfile(fn,"w");
1495 
1496 	merge_sub_lists(parts, n, f_out);
1497 
1498 	closefile(f_out, fn);
1499 }
1500 
1501 #endif /* defined(SORT_THREADS) */
1502 /*
1503  * Multi-threaded sort algorithm "driver"
1504  */
1505 static void
1506 mt_sort(struct sort_list *list,
1507     int(*sort_func)(void *, size_t, size_t, int(*)(const void *, const void *)),
1508     const char* fn)
1509 {
1510 #if defined(SORT_THREADS)
1511 	if (nthreads < 2 || list->count < MT_SORT_THRESHOLD) {
1512 		size_t nthreads_save = nthreads;
1513 		nthreads = 1;
1514 #endif
1515 		/* if single thread or small data, do simple sort */
1516 		sort_func(list->list, list->count,
1517 		    sizeof(struct sort_list_item *),
1518 		    (int(*)(const void *, const void *)) list_coll);
1519 		sort_list_dump(list, fn);
1520 #if defined(SORT_THREADS)
1521 		nthreads = nthreads_save;
1522 	} else {
1523 		/* multi-threaded sort */
1524 		struct sort_list **parts;
1525 		size_t avgsize, cstart, i;
1526 
1527 		/* array of sub-lists */
1528 		parts = sort_malloc(sizeof(struct sort_list*) * nthreads);
1529 		cstart = 0;
1530 		avgsize = list->count / nthreads;
1531 
1532 		/* set global system sort function */
1533 		g_sort_func = sort_func;
1534 
1535 		/* set sublists */
1536 		for (i = 0; i < nthreads; ++i) {
1537 			size_t sz = 0;
1538 
1539 			parts[i] = sort_malloc(sizeof(struct sort_list));
1540 			parts[i]->list = list->list + cstart;
1541 			parts[i]->memsize = 0;
1542 			parts[i]->sub_list_pos = i;
1543 
1544 			sz = (i == nthreads - 1) ? list->count - cstart :
1545 			    avgsize;
1546 
1547 			parts[i]->count = sz;
1548 
1549 			parts[i]->size = parts[i]->count;
1550 
1551 			cstart += sz;
1552 		}
1553 
1554 		/* init threads counting semaphore */
1555 		sem_init(&mtsem, 0, 0);
1556 
1557 		/* start threads */
1558 		for (i = 0; i < nthreads; ++i) {
1559 			pthread_t pth;
1560 			pthread_attr_t attr;
1561 
1562 			pthread_attr_init(&attr);
1563 			pthread_attr_setdetachstate(&attr, PTHREAD_DETACHED);
1564 
1565 			for (;;) {
1566 				int res = pthread_create(&pth, &attr,
1567 				    mt_sort_thread, parts[i]);
1568 
1569 				if (res >= 0)
1570 					break;
1571 				if (errno == EAGAIN) {
1572 					pthread_yield();
1573 					continue;
1574 				}
1575 				err(2, NULL);
1576 			}
1577 
1578 			pthread_attr_destroy(&attr);
1579 		}
1580 
1581 		/* wait for threads completion */
1582 		for (i = 0; i < nthreads; ++i) {
1583 			sem_wait(&mtsem);
1584 		}
1585 		/* destroy the semaphore - we do not need it anymore */
1586 		sem_destroy(&mtsem);
1587 
1588 		/* merge sorted sub-lists to the file */
1589 		merge_list_parts(parts, nthreads, fn);
1590 
1591 		/* free sub-lists data */
1592 		for (i = 0; i < nthreads; ++i) {
1593 			sort_free(parts[i]);
1594 		}
1595 		sort_free(parts);
1596 	}
1597 #endif /* defined(SORT_THREADS) */
1598 }
1599