1/*-
2 * Copyright (C) 2009 Gabor Kovesdan <gabor@FreeBSD.org>
3 * Copyright (C) 2012 Oleg Moskalenko <mom040267@gmail.com>
4 * All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 *    notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 *    notice, this list of conditions and the following disclaimer in the
13 *    documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25 * SUCH DAMAGE.
26 */
27
28#include <sys/cdefs.h>
29__FBSDID("$FreeBSD$");
30
31#include <sys/mman.h>
32#include <sys/stat.h>
33#include <sys/types.h>
34#include <sys/queue.h>
35
36#include <err.h>
37#include <fcntl.h>
38#if defined(SORT_THREADS)
39#include <pthread.h>
40#endif
41#include <semaphore.h>
42#include <stdio.h>
43#include <stdlib.h>
44#include <string.h>
45#include <unistd.h>
46#include <wchar.h>
47#include <wctype.h>
48
49#include "coll.h"
50#include "file.h"
51#include "radixsort.h"
52
53unsigned long long free_memory = 1000000;
54unsigned long long available_free_memory = 1000000;
55
56bool use_mmap;
57
58const char *tmpdir = "/var/tmp";
59const char *compress_program;
60
61size_t max_open_files = 16;
62
63/*
64 * How much space we read from file at once
65 */
66#define READ_CHUNK (4096)
67
68/*
69 * File reader structure
70 */
71struct file_reader
72{
73	struct reader_buffer	 rb;
74	FILE			*file;
75	char			*fname;
76	unsigned char		*buffer;
77	unsigned char		*mmapaddr;
78	unsigned char		*mmapptr;
79	size_t			 bsz;
80	size_t			 cbsz;
81	size_t			 mmapsize;
82	size_t			 strbeg;
83	int			 fd;
84	char			 elsymb;
85};
86
87/*
88 * Structure to be used in file merge process.
89 */
90struct file_header
91{
92	struct file_reader		*fr;
93	struct sort_list_item		*si; /* current top line */
94	size_t				 file_pos;
95};
96
97/*
98 * List elements of "cleanable" files list.
99 */
100struct CLEANABLE_FILE
101{
102	char				*fn;
103	LIST_ENTRY(CLEANABLE_FILE)	 files;
104};
105
106/*
107 * List header of "cleanable" files list.
108 */
109static LIST_HEAD(CLEANABLE_FILES,CLEANABLE_FILE) tmp_files;
110
111/*
112 * Semaphore to protect the tmp file list.
113 * We use semaphore here because it is signal-safe, according to POSIX.
114 * And semaphore does not require pthread library.
115 */
116static sem_t tmp_files_sem;
117
118static void mt_sort(struct sort_list *list,
119    int (*sort_func)(void *, size_t, size_t,
120    int (*)(const void *, const void *)), const char* fn);
121
122/*
123 * Init tmp files list
124 */
125void
126init_tmp_files(void)
127{
128
129	LIST_INIT(&tmp_files);
130	sem_init(&tmp_files_sem, 0, 1);
131}
132
133/*
134 * Save name of a tmp file for signal cleanup
135 */
136void
137tmp_file_atexit(const char *tmp_file)
138{
139
140	if (tmp_file) {
141		sem_wait(&tmp_files_sem);
142		struct CLEANABLE_FILE *item =
143		    sort_malloc(sizeof(struct CLEANABLE_FILE));
144		item->fn = sort_strdup(tmp_file);
145		LIST_INSERT_HEAD(&tmp_files, item, files);
146		sem_post(&tmp_files_sem);
147	}
148}
149
150/*
151 * Clear tmp files
152 */
153void
154clear_tmp_files(void)
155{
156	struct CLEANABLE_FILE *item;
157
158	sem_wait(&tmp_files_sem);
159	LIST_FOREACH(item,&tmp_files,files) {
160		if ((item) && (item->fn))
161			unlink(item->fn);
162	}
163	sem_post(&tmp_files_sem);
164}
165
166/*
167 * Check whether a file is a temporary file
168 */
169static bool
170file_is_tmp(const char* fn)
171{
172	struct CLEANABLE_FILE *item;
173	bool ret = false;
174
175	if (fn) {
176		sem_wait(&tmp_files_sem);
177		LIST_FOREACH(item,&tmp_files,files) {
178			if ((item) && (item->fn))
179				if (strcmp(item->fn, fn) == 0) {
180					ret = true;
181					break;
182				}
183		}
184		sem_post(&tmp_files_sem);
185	}
186
187	return (ret);
188}
189
190/*
191 * Generate new temporary file name
192 */
193char *
194new_tmp_file_name(void)
195{
196	static size_t tfcounter = 0;
197	static const char *fn = ".bsdsort.";
198	char *ret;
199	size_t sz;
200
201	sz = strlen(tmpdir) + 1 + strlen(fn) + 32 + 1;
202	ret = sort_malloc(sz);
203
204	sprintf(ret, "%s/%s%d.%lu", tmpdir, fn, (int) getpid(), (unsigned long)(tfcounter++));
205	tmp_file_atexit(ret);
206	return (ret);
207}
208
209/*
210 * Initialize file list
211 */
212void
213file_list_init(struct file_list *fl, bool tmp)
214{
215
216	if (fl) {
217		fl->count = 0;
218		fl->sz = 0;
219		fl->fns = NULL;
220		fl->tmp = tmp;
221	}
222}
223
224/*
225 * Add a file name to the list
226 */
227void
228file_list_add(struct file_list *fl, char *fn, bool allocate)
229{
230
231	if (fl && fn) {
232		if (fl->count >= fl->sz || (fl->fns == NULL)) {
233			fl->sz = (fl->sz) * 2 + 1;
234			fl->fns = sort_realloc(fl->fns, fl->sz *
235			    sizeof(char *));
236		}
237		fl->fns[fl->count] = allocate ? sort_strdup(fn) : fn;
238		fl->count += 1;
239	}
240}
241
242/*
243 * Populate file list from array of file names
244 */
245void
246file_list_populate(struct file_list *fl, int argc, char **argv, bool allocate)
247{
248
249	if (fl && argv) {
250		int i;
251
252		for (i = 0; i < argc; i++)
253			file_list_add(fl, argv[i], allocate);
254	}
255}
256
257/*
258 * Clean file list data and delete the files,
259 * if this is a list of temporary files
260 */
261void
262file_list_clean(struct file_list *fl)
263{
264
265	if (fl) {
266		if (fl->fns) {
267			size_t i;
268
269			for (i = 0; i < fl->count; i++) {
270				if (fl->fns[i]) {
271					if (fl->tmp)
272						unlink(fl->fns[i]);
273					sort_free(fl->fns[i]);
274					fl->fns[i] = 0;
275				}
276			}
277			sort_free(fl->fns);
278			fl->fns = NULL;
279		}
280		fl->sz = 0;
281		fl->count = 0;
282		fl->tmp = false;
283	}
284}
285
286/*
287 * Init sort list
288 */
289void
290sort_list_init(struct sort_list *l)
291{
292
293	if (l) {
294		l->count = 0;
295		l->size = 0;
296		l->memsize = sizeof(struct sort_list);
297		l->list = NULL;
298	}
299}
300
301/*
302 * Add string to sort list
303 */
304void
305sort_list_add(struct sort_list *l, struct bwstring *str)
306{
307
308	if (l && str) {
309		size_t indx = l->count;
310
311		if ((l->list == NULL) || (indx >= l->size)) {
312			size_t newsize = (l->size + 1) + 1024;
313
314			l->list = sort_realloc(l->list,
315			    sizeof(struct sort_list_item*) * newsize);
316			l->memsize += (newsize - l->size) *
317			    sizeof(struct sort_list_item*);
318			l->size = newsize;
319		}
320		l->list[indx] = sort_list_item_alloc();
321		sort_list_item_set(l->list[indx], str);
322		l->memsize += sort_list_item_size(l->list[indx]);
323		l->count += 1;
324	}
325}
326
327/*
328 * Clean sort list data
329 */
330void
331sort_list_clean(struct sort_list *l)
332{
333
334	if (l) {
335		if (l->list) {
336			size_t i;
337
338			for (i = 0; i < l->count; i++) {
339				struct sort_list_item *item;
340
341				item = l->list[i];
342
343				if (item) {
344					sort_list_item_clean(item);
345					sort_free(item);
346					l->list[i] = NULL;
347				}
348			}
349			sort_free(l->list);
350			l->list = NULL;
351		}
352		l->count = 0;
353		l->size = 0;
354		l->memsize = sizeof(struct sort_list);
355	}
356}
357
358/*
359 * Write sort list to file
360 */
361void
362sort_list_dump(struct sort_list *l, const char *fn)
363{
364
365	if (l && fn) {
366		FILE *f;
367
368		f = openfile(fn, "w");
369		if (f == NULL)
370			err(2, NULL);
371
372		if (l->list) {
373			size_t i;
374			if (!(sort_opts_vals.uflag)) {
375				for (i = 0; i < l->count; ++i)
376					bwsfwrite(l->list[i]->str, f,
377					    sort_opts_vals.zflag);
378			} else {
379				struct sort_list_item *last_printed_item = NULL;
380				struct sort_list_item *item;
381				for (i = 0; i < l->count; ++i) {
382					item = l->list[i];
383					if ((last_printed_item == NULL) ||
384					    list_coll(&last_printed_item, &item)) {
385						bwsfwrite(item->str, f, sort_opts_vals.zflag);
386						last_printed_item = item;
387					}
388				}
389			}
390		}
391
392		closefile(f, fn);
393	}
394}
395
396/*
397 * Checks if the given file is sorted.  Stops at the first disorder,
398 * prints the disordered line and returns 1.
399 */
400int
401check(const char *fn)
402{
403	struct bwstring *s1, *s2, *s1disorder, *s2disorder;
404	struct file_reader *fr;
405	struct keys_array *ka1, *ka2;
406	int res;
407	size_t pos, posdisorder;
408
409	s1 = s2 = s1disorder = s2disorder = NULL;
410	ka1 = ka2 = NULL;
411
412	fr = file_reader_init(fn);
413
414	res = 0;
415	pos = 1;
416	posdisorder = 1;
417
418	if (fr == NULL) {
419		err(2, NULL);
420		goto end;
421	}
422
423	s1 = file_reader_readline(fr);
424	if (s1 == NULL)
425		goto end;
426
427	ka1 = keys_array_alloc();
428	preproc(s1, ka1);
429
430	s2 = file_reader_readline(fr);
431	if (s2 == NULL)
432		goto end;
433
434	ka2 = keys_array_alloc();
435	preproc(s2, ka2);
436
437	for (;;) {
438
439		if (debug_sort) {
440			bwsprintf(stdout, s2, "s1=<", ">");
441			bwsprintf(stdout, s1, "s2=<", ">");
442		}
443		int cmp = key_coll(ka2, ka1, 0);
444		if (debug_sort)
445			printf("; cmp1=%d", cmp);
446
447		if (!cmp && sort_opts_vals.complex_sort &&
448		    !(sort_opts_vals.uflag) && !(sort_opts_vals.sflag)) {
449			cmp = top_level_str_coll(s2, s1);
450			if (debug_sort)
451				printf("; cmp2=%d", cmp);
452		}
453		if (debug_sort)
454			printf("\n");
455
456		if ((sort_opts_vals.uflag && (cmp <= 0)) || (cmp < 0)) {
457			if (!(sort_opts_vals.csilentflag)) {
458				s2disorder = bwsdup(s2);
459				posdisorder = pos;
460				if (debug_sort)
461					s1disorder = bwsdup(s1);
462			}
463			res = 1;
464			goto end;
465		}
466
467		pos++;
468
469		clean_keys_array(s1, ka1);
470		sort_free(ka1);
471		ka1 = ka2;
472		ka2 = NULL;
473
474		bwsfree(s1);
475		s1 = s2;
476
477		s2 = file_reader_readline(fr);
478		if (s2 == NULL)
479			goto end;
480
481		ka2 = keys_array_alloc();
482		preproc(s2, ka2);
483	}
484
485end:
486	if (ka1) {
487		clean_keys_array(s1, ka1);
488		sort_free(ka1);
489	}
490
491	if (s1)
492		bwsfree(s1);
493
494	if (ka2) {
495		clean_keys_array(s2, ka2);
496		sort_free(ka2);
497	}
498
499	if (s2)
500		bwsfree(s2);
501
502	if ((fn == NULL) || (*fn == 0) || (strcmp(fn, "-") == 0)) {
503		for (;;) {
504			s2 = file_reader_readline(fr);
505			if (s2 == NULL)
506				break;
507			bwsfree(s2);
508		}
509	}
510
511	file_reader_free(fr);
512
513	if (s2disorder) {
514		bws_disorder_warnx(s2disorder, fn, posdisorder);
515		if (s1disorder) {
516			bws_disorder_warnx(s1disorder, fn, posdisorder);
517			if (s1disorder != s2disorder)
518				bwsfree(s1disorder);
519		}
520		bwsfree(s2disorder);
521		s1disorder = NULL;
522		s2disorder = NULL;
523	}
524
525	if (res)
526		exit(res);
527
528	return (0);
529}
530
531/*
532 * Opens a file.  If the given filename is "-", stdout will be
533 * opened.
534 */
535FILE *
536openfile(const char *fn, const char *mode)
537{
538	FILE *file;
539
540	if (strcmp(fn, "-") == 0) {
541		return ((mode && mode[0] == 'r') ? stdin : stdout);
542	} else {
543		mode_t orig_file_mask = 0;
544		int is_tmp = file_is_tmp(fn);
545
546		if (is_tmp && (mode[0] == 'w'))
547			orig_file_mask = umask(S_IWGRP | S_IWOTH |
548			    S_IRGRP | S_IROTH);
549
550		if (is_tmp && (compress_program != NULL)) {
551			char *cmd;
552			size_t cmdsz;
553
554			cmdsz = strlen(fn) + 128;
555			cmd = sort_malloc(cmdsz);
556
557			fflush(stdout);
558
559			if (mode[0] == 'r')
560				snprintf(cmd, cmdsz - 1, "cat %s | %s -d",
561				    fn, compress_program);
562			else if (mode[0] == 'w')
563				snprintf(cmd, cmdsz - 1, "%s > %s",
564				    compress_program, fn);
565			else
566				err(2, "%s", getstr(7));
567
568			if ((file = popen(cmd, mode)) == NULL)
569				err(2, NULL);
570
571			sort_free(cmd);
572
573		} else
574			if ((file = fopen(fn, mode)) == NULL)
575				err(2, NULL);
576
577		if (is_tmp && (mode[0] == 'w'))
578			umask(orig_file_mask);
579	}
580
581	return (file);
582}
583
584/*
585 * Close file
586 */
587void
588closefile(FILE *f, const char *fn)
589{
590	if (f == NULL) {
591		;
592	} else if (f == stdin) {
593		;
594	} else if (f == stdout) {
595		fflush(f);
596	} else {
597		if (file_is_tmp(fn) && compress_program != NULL) {
598			if(pclose(f)<0)
599				err(2,NULL);
600		} else
601			fclose(f);
602	}
603}
604
605/*
606 * Reads a file into the internal buffer.
607 */
608struct file_reader *
609file_reader_init(const char *fsrc)
610{
611	struct file_reader *ret;
612
613	if (fsrc == NULL)
614		fsrc = "-";
615
616	ret = sort_malloc(sizeof(struct file_reader));
617	memset(ret, 0, sizeof(struct file_reader));
618
619	ret->elsymb = '\n';
620	if (sort_opts_vals.zflag)
621		ret->elsymb = 0;
622
623	ret->fname = sort_strdup(fsrc);
624
625	if (strcmp(fsrc, "-") && (compress_program == NULL) && use_mmap) {
626
627		do {
628			struct stat stat_buf;
629			void *addr;
630			size_t sz = 0;
631			int fd, flags;
632
633			flags = MAP_NOCORE | MAP_NOSYNC;
634			addr = MAP_FAILED;
635
636			fd = open(fsrc, O_RDONLY);
637			if (fd < 0)
638				err(2, NULL);
639
640			if (fstat(fd, &stat_buf) < 0) {
641				close(fd);
642				break;
643			}
644
645			sz = stat_buf.st_size;
646
647#if defined(MAP_PREFAULT_READ)
648			flags |= MAP_PREFAULT_READ;
649#endif
650
651			addr = mmap(NULL, sz, PROT_READ, flags, fd, 0);
652			if (addr == MAP_FAILED) {
653				close(fd);
654				break;
655			}
656
657			ret->fd = fd;
658			ret->mmapaddr = addr;
659			ret->mmapsize = sz;
660			ret->mmapptr = ret->mmapaddr;
661
662		} while (0);
663	}
664
665	if (ret->mmapaddr == NULL) {
666		ret->file = openfile(fsrc, "r");
667		if (ret->file == NULL)
668			err(2, NULL);
669
670		if (strcmp(fsrc, "-")) {
671			ret->cbsz = READ_CHUNK;
672			ret->buffer = sort_malloc(ret->cbsz);
673			ret->bsz = 0;
674			ret->strbeg = 0;
675
676			ret->bsz = fread(ret->buffer, 1, ret->cbsz, ret->file);
677			if (ret->bsz == 0) {
678				if (ferror(ret->file))
679					err(2, NULL);
680			}
681		}
682	}
683
684	return (ret);
685}
686
687struct bwstring *
688file_reader_readline(struct file_reader *fr)
689{
690	struct bwstring *ret = NULL;
691
692	if (fr->mmapaddr) {
693		unsigned char *mmapend;
694
695		mmapend = fr->mmapaddr + fr->mmapsize;
696		if (fr->mmapptr >= mmapend)
697			return (NULL);
698		else {
699			unsigned char *strend;
700			size_t sz;
701
702			sz = mmapend - fr->mmapptr;
703			strend = memchr(fr->mmapptr, fr->elsymb, sz);
704
705			if (strend == NULL) {
706				ret = bwscsbdup(fr->mmapptr, sz);
707				fr->mmapptr = mmapend;
708			} else {
709				ret = bwscsbdup(fr->mmapptr, strend -
710				    fr->mmapptr);
711				fr->mmapptr = strend + 1;
712			}
713		}
714
715	} else if (fr->file != stdin) {
716		unsigned char *strend;
717		size_t bsz1, remsz, search_start;
718
719		search_start = 0;
720		remsz = 0;
721		strend = NULL;
722
723		if (fr->bsz > fr->strbeg)
724			remsz = fr->bsz - fr->strbeg;
725
726		/* line read cycle */
727		for (;;) {
728			if (remsz > search_start)
729				strend = memchr(fr->buffer + fr->strbeg +
730				    search_start, fr->elsymb, remsz -
731				    search_start);
732			else
733				strend = NULL;
734
735			if (strend)
736				break;
737			if (feof(fr->file))
738				break;
739
740			if (fr->bsz != fr->cbsz)
741				/* NOTREACHED */
742				err(2, "File read software error 1");
743
744			if (remsz > (READ_CHUNK >> 1)) {
745				search_start = fr->cbsz - fr->strbeg;
746				fr->cbsz += READ_CHUNK;
747				fr->buffer = sort_realloc(fr->buffer,
748				    fr->cbsz);
749				bsz1 = fread(fr->buffer + fr->bsz, 1,
750				    READ_CHUNK, fr->file);
751				if (bsz1 == 0) {
752					if (ferror(fr->file))
753						err(2, NULL);
754					break;
755				}
756				fr->bsz += bsz1;
757				remsz += bsz1;
758			} else {
759				if (remsz > 0 && fr->strbeg>0)
760					bcopy(fr->buffer + fr->strbeg,
761					    fr->buffer, remsz);
762
763				fr->strbeg = 0;
764				search_start = remsz;
765				bsz1 = fread(fr->buffer + remsz, 1,
766				    fr->cbsz - remsz, fr->file);
767				if (bsz1 == 0) {
768					if (ferror(fr->file))
769						err(2, NULL);
770					break;
771				}
772				fr->bsz = remsz + bsz1;
773				remsz = fr->bsz;
774			}
775		}
776
777		if (strend == NULL)
778			strend = fr->buffer + fr->bsz;
779
780		if ((fr->buffer + fr->strbeg <= strend) &&
781		    (fr->strbeg < fr->bsz) && (remsz>0))
782			ret = bwscsbdup(fr->buffer + fr->strbeg, strend -
783			    fr->buffer - fr->strbeg);
784
785		fr->strbeg = (strend - fr->buffer) + 1;
786
787	} else {
788		size_t len = 0;
789
790		ret = bwsfgetln(fr->file, &len, sort_opts_vals.zflag,
791		    &(fr->rb));
792	}
793
794	return (ret);
795}
796
797static void
798file_reader_clean(struct file_reader *fr)
799{
800
801	if (fr) {
802		if (fr->mmapaddr)
803			munmap(fr->mmapaddr, fr->mmapsize);
804
805		if (fr->fd)
806			close(fr->fd);
807
808		if (fr->buffer)
809			sort_free(fr->buffer);
810
811		if (fr->file)
812			if (fr->file != stdin)
813				closefile(fr->file, fr->fname);
814
815		if(fr->fname)
816			sort_free(fr->fname);
817
818		memset(fr, 0, sizeof(struct file_reader));
819	}
820}
821
822void
823file_reader_free(struct file_reader *fr)
824{
825
826	if (fr) {
827		file_reader_clean(fr);
828		sort_free(fr);
829	}
830}
831
832int
833procfile(const char *fsrc, struct sort_list *list, struct file_list *fl)
834{
835	struct file_reader *fr;
836
837	fr = file_reader_init(fsrc);
838	if (fr == NULL)
839		err(2, NULL);
840
841	/* file browse cycle */
842	for (;;) {
843		struct bwstring *bws;
844
845		bws = file_reader_readline(fr);
846
847		if (bws == NULL)
848			break;
849
850		sort_list_add(list, bws);
851
852		if (list->memsize >= available_free_memory) {
853			char *fn;
854
855			fn = new_tmp_file_name();
856			sort_list_to_file(list, fn);
857			file_list_add(fl, fn, false);
858			sort_list_clean(list);
859		}
860	}
861
862	file_reader_free(fr);
863
864	return (0);
865}
866
867/*
868 * Compare file headers. Files with EOF always go to the end of the list.
869 */
870static int
871file_header_cmp(struct file_header *f1, struct file_header *f2)
872{
873
874	if (f1 == f2)
875		return (0);
876	else {
877		if (f1->fr == NULL) {
878			return ((f2->fr == NULL) ? 0 : +1);
879		} else if (f2->fr == NULL)
880			return (-1);
881		else {
882			int ret;
883
884			ret = list_coll(&(f1->si), &(f2->si));
885			if (!ret)
886				return ((f1->file_pos < f2->file_pos) ? -1 : +1);
887			return (ret);
888		}
889	}
890}
891
892/*
893 * Allocate and init file header structure
894 */
895static void
896file_header_init(struct file_header **fh, const char *fn, size_t file_pos)
897{
898
899	if (fh && fn) {
900		struct bwstring *line;
901
902		*fh = sort_malloc(sizeof(struct file_header));
903		(*fh)->file_pos = file_pos;
904		(*fh)->fr = file_reader_init(fn);
905		if ((*fh)->fr == NULL) {
906			perror(fn);
907			err(2, "%s", getstr(8));
908		}
909		line = file_reader_readline((*fh)->fr);
910		if (line == NULL) {
911			file_reader_free((*fh)->fr);
912			(*fh)->fr = NULL;
913			(*fh)->si = NULL;
914		} else {
915			(*fh)->si = sort_list_item_alloc();
916			sort_list_item_set((*fh)->si, line);
917		}
918	}
919}
920
921/*
922 * Close file
923 */
924static void
925file_header_close(struct file_header **fh)
926{
927
928	if (fh && *fh) {
929		if ((*fh)->fr) {
930			file_reader_free((*fh)->fr);
931			(*fh)->fr = NULL;
932		}
933		if ((*fh)->si) {
934			sort_list_item_clean((*fh)->si);
935			sort_free((*fh)->si);
936			(*fh)->si = NULL;
937		}
938		sort_free(*fh);
939		*fh = NULL;
940	}
941}
942
943/*
944 * Swap two array elements
945 */
946static void
947file_header_swap(struct file_header **fh, size_t i1, size_t i2)
948{
949	struct file_header *tmp;
950
951	tmp = fh[i1];
952	fh[i1] = fh[i2];
953	fh[i2] = tmp;
954}
955
956/* heap algorithm ==>> */
957
958/*
959 * See heap sort algorithm
960 * "Raises" last element to its right place
961 */
962static void
963file_header_heap_swim(struct file_header **fh, size_t indx)
964{
965
966	if (indx > 0) {
967		size_t parent_index;
968
969		parent_index = (indx - 1) >> 1;
970
971		if (file_header_cmp(fh[indx], fh[parent_index]) < 0) {
972			/* swap child and parent and continue */
973			file_header_swap(fh, indx, parent_index);
974			file_header_heap_swim(fh, parent_index);
975		}
976	}
977}
978
979/*
980 * Sink the top element to its correct position
981 */
982static void
983file_header_heap_sink(struct file_header **fh, size_t indx, size_t size)
984{
985	size_t left_child_index;
986	size_t right_child_index;
987
988	left_child_index = indx + indx + 1;
989	right_child_index = left_child_index + 1;
990
991	if (left_child_index < size) {
992		size_t min_child_index;
993
994		min_child_index = left_child_index;
995
996		if ((right_child_index < size) &&
997		    (file_header_cmp(fh[left_child_index],
998		    fh[right_child_index]) > 0))
999			min_child_index = right_child_index;
1000		if (file_header_cmp(fh[indx], fh[min_child_index]) > 0) {
1001			file_header_swap(fh, indx, min_child_index);
1002			file_header_heap_sink(fh, min_child_index, size);
1003		}
1004	}
1005}
1006
1007/* <<== heap algorithm */
1008
1009/*
1010 * Adds element to the "left" end
1011 */
1012static void
1013file_header_list_rearrange_from_header(struct file_header **fh, size_t size)
1014{
1015
1016	file_header_heap_sink(fh, 0, size);
1017}
1018
1019/*
1020 * Adds element to the "right" end
1021 */
1022static void
1023file_header_list_push(struct file_header *f, struct file_header **fh, size_t size)
1024{
1025
1026	fh[size++] = f;
1027	file_header_heap_swim(fh, size - 1);
1028}
1029
1030struct last_printed
1031{
1032	struct bwstring *str;
1033};
1034
1035/*
1036 * Prints the current line of the file
1037 */
1038static void
1039file_header_print(struct file_header *fh, FILE *f_out, struct last_printed *lp)
1040{
1041
1042	if (fh && fh->fr && f_out && fh->si && fh->si->str) {
1043		if (sort_opts_vals.uflag) {
1044			if ((lp->str == NULL) || (str_list_coll(lp->str, &(fh->si)))) {
1045				bwsfwrite(fh->si->str, f_out, sort_opts_vals.zflag);
1046				if (lp->str)
1047					bwsfree(lp->str);
1048				lp->str = bwsdup(fh->si->str);
1049			}
1050		} else
1051			bwsfwrite(fh->si->str, f_out, sort_opts_vals.zflag);
1052	}
1053}
1054
1055/*
1056 * Read next line
1057 */
1058static void
1059file_header_read_next(struct file_header *fh)
1060{
1061
1062	if (fh && fh->fr) {
1063		struct bwstring *tmp;
1064
1065		tmp = file_reader_readline(fh->fr);
1066		if (tmp == NULL) {
1067			file_reader_free(fh->fr);
1068			fh->fr = NULL;
1069			if (fh->si) {
1070				sort_list_item_clean(fh->si);
1071				sort_free(fh->si);
1072				fh->si = NULL;
1073			}
1074		} else {
1075			if (fh->si == NULL)
1076				fh->si = sort_list_item_alloc();
1077			sort_list_item_set(fh->si, tmp);
1078		}
1079	}
1080}
1081
1082/*
1083 * Merge array of "files headers"
1084 */
1085static void
1086file_headers_merge(size_t fnum, struct file_header **fh, FILE *f_out)
1087{
1088	struct last_printed lp;
1089	size_t i;
1090
1091	memset(&lp, 0, sizeof(lp));
1092
1093	/*
1094	 * construct the initial sort structure
1095	 */
1096	for (i = 0; i < fnum; i++)
1097		file_header_list_push(fh[i], fh, i);
1098
1099	while (fh[0]->fr) { /* unfinished files are always in front */
1100		/* output the smallest line: */
1101		file_header_print(fh[0], f_out, &lp);
1102		/* read a new line, if possible: */
1103		file_header_read_next(fh[0]);
1104		/* re-arrange the list: */
1105		file_header_list_rearrange_from_header(fh, fnum);
1106	}
1107
1108	if (lp.str)
1109		bwsfree(lp.str);
1110}
1111
1112/*
1113 * Merges the given files into the output file, which can be
1114 * stdout.
1115 */
1116static void
1117merge_files_array(size_t argc, char **argv, const char *fn_out)
1118{
1119
1120	if (argv && fn_out) {
1121		struct file_header **fh;
1122		FILE *f_out;
1123		size_t i;
1124
1125		f_out = openfile(fn_out, "w");
1126
1127		if (f_out == NULL)
1128			err(2, NULL);
1129
1130		fh = sort_malloc((argc + 1) * sizeof(struct file_header *));
1131
1132		for (i = 0; i < argc; i++)
1133			file_header_init(fh + i, argv[i], (size_t) i);
1134
1135		file_headers_merge(argc, fh, f_out);
1136
1137		for (i = 0; i < argc; i++)
1138			file_header_close(fh + i);
1139
1140		sort_free(fh);
1141
1142		closefile(f_out, fn_out);
1143	}
1144}
1145
1146/*
1147 * Shrinks the file list until its size smaller than max number of opened files
1148 */
1149static int
1150shrink_file_list(struct file_list *fl)
1151{
1152
1153	if ((fl == NULL) || (size_t) (fl->count) < max_open_files)
1154		return (0);
1155	else {
1156		struct file_list new_fl;
1157		size_t indx = 0;
1158
1159		file_list_init(&new_fl, true);
1160		while (indx < fl->count) {
1161			char *fnew;
1162			size_t num;
1163
1164			num = fl->count - indx;
1165			fnew = new_tmp_file_name();
1166
1167			if ((size_t) num >= max_open_files)
1168				num = max_open_files - 1;
1169			merge_files_array(num, fl->fns + indx, fnew);
1170			if (fl->tmp) {
1171				size_t i;
1172
1173				for (i = 0; i < num; i++)
1174					unlink(fl->fns[indx + i]);
1175			}
1176			file_list_add(&new_fl, fnew, false);
1177			indx += num;
1178		}
1179		fl->tmp = false; /* already taken care of */
1180		file_list_clean(fl);
1181
1182		fl->count = new_fl.count;
1183		fl->fns = new_fl.fns;
1184		fl->sz = new_fl.sz;
1185		fl->tmp = new_fl.tmp;
1186
1187		return (1);
1188	}
1189}
1190
1191/*
1192 * Merge list of files
1193 */
1194void
1195merge_files(struct file_list *fl, const char *fn_out)
1196{
1197
1198	if (fl && fn_out) {
1199		while (shrink_file_list(fl));
1200
1201		merge_files_array(fl->count, fl->fns, fn_out);
1202	}
1203}
1204
1205static const char *
1206get_sort_method_name(int sm)
1207{
1208
1209	if (sm == SORT_MERGESORT)
1210		return "mergesort";
1211	else if (sort_opts_vals.sort_method == SORT_RADIXSORT)
1212		return "radixsort";
1213	else if (sort_opts_vals.sort_method == SORT_HEAPSORT)
1214		return "heapsort";
1215	else
1216		return "quicksort";
1217}
1218
1219/*
1220 * Wrapper for qsort
1221 */
1222static int sort_qsort(void *list, size_t count, size_t elem_size,
1223    int (*cmp_func)(const void *, const void *))
1224{
1225
1226	qsort(list, count, elem_size, cmp_func);
1227	return (0);
1228}
1229
1230/*
1231 * Sort list of lines and writes it to the file
1232 */
1233void
1234sort_list_to_file(struct sort_list *list, const char *outfile)
1235{
1236	struct sort_mods *sm = &(keys[0].sm);
1237
1238	if (!(sm->Mflag) && !(sm->Rflag) && !(sm->Vflag) && !(sm->Vflag) &&
1239	    !(sm->gflag) && !(sm->hflag) && !(sm->nflag)) {
1240		if ((sort_opts_vals.sort_method == SORT_DEFAULT) && byte_sort)
1241			sort_opts_vals.sort_method = SORT_RADIXSORT;
1242
1243	} else if (sort_opts_vals.sort_method == SORT_RADIXSORT)
1244		err(2, "%s", getstr(9));
1245
1246	/*
1247	 * to handle stable sort and the unique cases in the
1248	 * right order, we need stable basic algorithm
1249	 */
1250	if (sort_opts_vals.sflag) {
1251		switch (sort_opts_vals.sort_method){
1252		case SORT_MERGESORT:
1253			break;
1254		case SORT_RADIXSORT:
1255			break;
1256		case SORT_DEFAULT:
1257			sort_opts_vals.sort_method = SORT_MERGESORT;
1258			break;
1259		default:
1260			errx(2, "%s", getstr(10));
1261		};
1262	}
1263
1264	if (sort_opts_vals.sort_method == SORT_DEFAULT)
1265		sort_opts_vals.sort_method = DEFAULT_SORT_ALGORITHM;
1266
1267	if (debug_sort)
1268		printf("sort_method=%s\n",
1269		    get_sort_method_name(sort_opts_vals.sort_method));
1270
1271	switch (sort_opts_vals.sort_method){
1272	case SORT_RADIXSORT:
1273		rxsort(list->list, list->count);
1274		sort_list_dump(list, outfile);
1275		break;
1276	case SORT_MERGESORT:
1277		mt_sort(list, mergesort, outfile);
1278		break;
1279	case SORT_HEAPSORT:
1280		mt_sort(list, heapsort,	outfile);
1281		break;
1282	case SORT_QSORT:
1283		mt_sort(list, sort_qsort, outfile);
1284		break;
1285	default:
1286		mt_sort(list, DEFAULT_SORT_FUNC, outfile);
1287		break;
1288	}
1289}
1290
1291/******************* MT SORT ************************/
1292
1293#if defined(SORT_THREADS)
1294/* semaphore to count threads */
1295static sem_t mtsem;
1296
1297/* current system sort function */
1298static int (*g_sort_func)(void *, size_t, size_t,
1299    int(*)(const void *, const void *));
1300
1301/*
1302 * Sort cycle thread (in multi-threaded mode)
1303 */
1304static void*
1305mt_sort_thread(void* arg)
1306{
1307	struct sort_list *list = arg;
1308
1309	g_sort_func(list->list, list->count, sizeof(struct sort_list_item *),
1310	    (int(*)(const void *, const void *)) list_coll);
1311
1312	sem_post(&mtsem);
1313
1314	return (arg);
1315}
1316
1317/*
1318 * Compare sub-lists. Empty sub-lists always go to the end of the list.
1319 */
1320static int
1321sub_list_cmp(struct sort_list *l1, struct sort_list *l2)
1322{
1323
1324	if (l1 == l2)
1325		return (0);
1326	else {
1327		if (l1->count == 0) {
1328			return ((l2->count == 0) ? 0 : +1);
1329		} else if (l2->count == 0) {
1330			return (-1);
1331		} else {
1332			int ret;
1333
1334			ret = list_coll(&(l1->list[0]), &(l2->list[0]));
1335			if (!ret)
1336				return ((l1->sub_list_pos < l2->sub_list_pos) ?
1337				    -1 : +1);
1338			return (ret);
1339		}
1340	}
1341}
1342
1343/*
1344 * Swap two array elements
1345 */
1346static void
1347sub_list_swap(struct sort_list **sl, size_t i1, size_t i2)
1348{
1349	struct sort_list *tmp;
1350
1351	tmp = sl[i1];
1352	sl[i1] = sl[i2];
1353	sl[i2] = tmp;
1354}
1355
1356/* heap algorithm ==>> */
1357
1358/*
1359 * See heap sort algorithm
1360 * "Raises" last element to its right place
1361 */
1362static void
1363sub_list_swim(struct sort_list **sl, size_t indx)
1364{
1365
1366	if (indx > 0) {
1367		size_t parent_index;
1368
1369		parent_index = (indx - 1) >> 1;
1370
1371		if (sub_list_cmp(sl[indx], sl[parent_index]) < 0) {
1372			/* swap child and parent and continue */
1373			sub_list_swap(sl, indx, parent_index);
1374			sub_list_swim(sl, parent_index);
1375		}
1376	}
1377}
1378
1379/*
1380 * Sink the top element to its correct position
1381 */
1382static void
1383sub_list_sink(struct sort_list **sl, size_t indx, size_t size)
1384{
1385	size_t left_child_index;
1386	size_t right_child_index;
1387
1388	left_child_index = indx + indx + 1;
1389	right_child_index = left_child_index + 1;
1390
1391	if (left_child_index < size) {
1392		size_t min_child_index;
1393
1394		min_child_index = left_child_index;
1395
1396		if ((right_child_index < size) &&
1397		    (sub_list_cmp(sl[left_child_index],
1398		    sl[right_child_index]) > 0))
1399			min_child_index = right_child_index;
1400		if (sub_list_cmp(sl[indx], sl[min_child_index]) > 0) {
1401			sub_list_swap(sl, indx, min_child_index);
1402			sub_list_sink(sl, min_child_index, size);
1403		}
1404	}
1405}
1406
1407/* <<== heap algorithm */
1408
1409/*
1410 * Adds element to the "right" end
1411 */
1412static void
1413sub_list_push(struct sort_list *s, struct sort_list **sl, size_t size)
1414{
1415
1416	sl[size++] = s;
1417	sub_list_swim(sl, size - 1);
1418}
1419
1420struct last_printed_item
1421{
1422	struct sort_list_item *item;
1423};
1424
1425/*
1426 * Prints the current line of the file
1427 */
1428static void
1429sub_list_header_print(struct sort_list *sl, FILE *f_out,
1430    struct last_printed_item *lp)
1431{
1432
1433	if (sl && sl->count && f_out && sl->list[0]->str) {
1434		if (sort_opts_vals.uflag) {
1435			if ((lp->item == NULL) || (list_coll(&(lp->item),
1436			    &(sl->list[0])))) {
1437				bwsfwrite(sl->list[0]->str, f_out,
1438				    sort_opts_vals.zflag);
1439				lp->item = sl->list[0];
1440			}
1441		} else
1442			bwsfwrite(sl->list[0]->str, f_out,
1443			    sort_opts_vals.zflag);
1444	}
1445}
1446
1447/*
1448 * Read next line
1449 */
1450static void
1451sub_list_next(struct sort_list *sl)
1452{
1453
1454	if (sl && sl->count) {
1455		sl->list += 1;
1456		sl->count -= 1;
1457	}
1458}
1459
1460/*
1461 * Merge sub-lists to a file
1462 */
1463static void
1464merge_sub_lists(struct sort_list **sl, size_t n, FILE* f_out)
1465{
1466	struct last_printed_item lp;
1467	size_t i;
1468
1469	memset(&lp,0,sizeof(lp));
1470
1471	/* construct the initial list: */
1472	for (i = 0; i < n; i++)
1473		sub_list_push(sl[i], sl, i);
1474
1475	while (sl[0]->count) { /* unfinished lists are always in front */
1476		/* output the smallest line: */
1477		sub_list_header_print(sl[0], f_out, &lp);
1478		/* move to a new line, if possible: */
1479		sub_list_next(sl[0]);
1480		/* re-arrange the list: */
1481		sub_list_sink(sl, 0, n);
1482	}
1483}
1484
1485/*
1486 * Merge sub-lists to a file
1487 */
1488static void
1489merge_list_parts(struct sort_list **parts, size_t n, const char *fn)
1490{
1491	FILE* f_out;
1492
1493	f_out = openfile(fn,"w");
1494
1495	merge_sub_lists(parts, n, f_out);
1496
1497	closefile(f_out, fn);
1498}
1499
1500#endif /* defined(SORT_THREADS) */
1501/*
1502 * Multi-threaded sort algorithm "driver"
1503 */
1504static void
1505mt_sort(struct sort_list *list,
1506    int(*sort_func)(void *, size_t, size_t, int(*)(const void *, const void *)),
1507    const char* fn)
1508{
1509#if defined(SORT_THREADS)
1510	if (nthreads < 2 || list->count < MT_SORT_THRESHOLD) {
1511		size_t nthreads_save = nthreads;
1512		nthreads = 1;
1513#endif
1514		/* if single thread or small data, do simple sort */
1515		sort_func(list->list, list->count,
1516		    sizeof(struct sort_list_item *),
1517		    (int(*)(const void *, const void *)) list_coll);
1518		sort_list_dump(list, fn);
1519#if defined(SORT_THREADS)
1520		nthreads = nthreads_save;
1521	} else {
1522		/* multi-threaded sort */
1523		struct sort_list **parts;
1524		size_t avgsize, cstart, i;
1525
1526		/* array of sub-lists */
1527		parts = sort_malloc(sizeof(struct sort_list*) * nthreads);
1528		cstart = 0;
1529		avgsize = list->count / nthreads;
1530
1531		/* set global system sort function */
1532		g_sort_func = sort_func;
1533
1534		/* set sublists */
1535		for (i = 0; i < nthreads; ++i) {
1536			size_t sz = 0;
1537
1538			parts[i] = sort_malloc(sizeof(struct sort_list));
1539			parts[i]->list = list->list + cstart;
1540			parts[i]->memsize = 0;
1541			parts[i]->sub_list_pos = i;
1542
1543			sz = (i == nthreads - 1) ? list->count - cstart :
1544			    avgsize;
1545
1546			parts[i]->count = sz;
1547
1548			parts[i]->size = parts[i]->count;
1549
1550			cstart += sz;
1551		}
1552
1553		/* init threads counting semaphore */
1554		sem_init(&mtsem, 0, 0);
1555
1556		/* start threads */
1557		for (i = 0; i < nthreads; ++i) {
1558			pthread_t pth;
1559			pthread_attr_t attr;
1560
1561			pthread_attr_init(&attr);
1562			pthread_attr_setdetachstate(&attr, PTHREAD_DETACHED);
1563
1564			for (;;) {
1565				int res = pthread_create(&pth, &attr,
1566				    mt_sort_thread, parts[i]);
1567
1568				if (res >= 0)
1569					break;
1570				if (errno == EAGAIN) {
1571					pthread_yield();
1572					continue;
1573				}
1574				err(2, NULL);
1575			}
1576
1577			pthread_attr_destroy(&attr);
1578		}
1579
1580		/* wait for threads completion */
1581		for (i = 0; i < nthreads; ++i) {
1582			sem_wait(&mtsem);
1583		}
1584		/* destroy the semaphore - we do not need it anymore */
1585		sem_destroy(&mtsem);
1586
1587		/* merge sorted sub-lists to the file */
1588		merge_list_parts(parts, nthreads, fn);
1589
1590		/* free sub-lists data */
1591		for (i = 0; i < nthreads; ++i) {
1592			sort_free(parts[i]);
1593		}
1594		sort_free(parts);
1595	}
1596#endif /* defined(SORT_THREADS) */
1597}
1598