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
55unsigned long long free_memory = 1000000;
56unsigned long long available_free_memory = 1000000;
57
58bool use_mmap;
59
60const char *tmpdir = "/var/tmp";
61const char *compress_program;
62
63size_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 */
73struct 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 */
92struct 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 */
102struct CLEANABLE_FILE
103{
104	char				*fn;
105	LIST_ENTRY(CLEANABLE_FILE)	 files;
106};
107
108/*
109 * List header of "cleanable" files list.
110 */
111static 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 */
118static sem_t tmp_files_sem;
119
120static 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 */
127void
128init_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 */
138void
139tmp_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 */
155void
156clear_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 */
171static bool
172file_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 */
195char *
196new_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 */
214void
215file_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 */
229void
230file_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 */
247void
248file_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 */
263void
264file_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 */
291void
292sort_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 */
306void
307sort_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 */
332void
333sort_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 */
363void
364sort_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 */
402int
403check(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
487end:
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 */
537FILE *
538openfile(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 */
589void
590closefile(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 */
610struct file_reader *
611file_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
688struct bwstring *
689file_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
798static void
799file_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
823void
824file_reader_free(struct file_reader *fr)
825{
826
827	if (fr) {
828		file_reader_clean(fr);
829		sort_free(fr);
830	}
831}
832
833int
834procfile(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 */
871static int
872file_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 */
896static void
897file_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 */
925static void
926file_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 */
947static void
948file_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 */
963static void
964file_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 */
983static void
984file_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 */
1013static void
1014file_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 */
1023static void
1024file_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
1031struct last_printed
1032{
1033	struct bwstring *str;
1034};
1035
1036/*
1037 * Prints the current line of the file
1038 */
1039static void
1040file_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 */
1059static void
1060file_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 */
1086static void
1087file_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 */
1117static void
1118merge_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 */
1150static int
1151shrink_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 */
1195void
1196merge_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
1206static const char *
1207get_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 */
1223static 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 */
1234void
1235sort_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 */
1296static sem_t mtsem;
1297
1298/* current system sort function */
1299static 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 */
1305static void*
1306mt_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 */
1321static int
1322sub_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 */
1347static void
1348sub_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 */
1363static void
1364sub_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 */
1383static void
1384sub_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 */
1413static void
1414sub_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
1421struct last_printed_item
1422{
1423	struct sort_list_item *item;
1424};
1425
1426/*
1427 * Prints the current line of the file
1428 */
1429static void
1430sub_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 */
1451static void
1452sub_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 */
1464static void
1465merge_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 */
1489static void
1490merge_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 */
1505static void
1506mt_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