aboutsummaryrefslogtreecommitdiff
path: root/src/im-sandbox.c
blob: eb823683fa3ec9673eccc50d45d83969c98b1d71 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
/*
 * im-sandbox.c
 *
 * Sandbox for indexing
 *
 * Copyright © 2012 Deutsches Elektronen-Synchrotron DESY,
 *                  a research centre of the Helmholtz Association.
 * Copyright © 2012 Richard Kirian
 * Copyright © 2012 Lorenzo Galli
 *
 * Authors:
 *   2010-2012 Thomas White <taw@physics.org>
 *   2011      Richard Kirian
 *   2012      Lorenzo Galli
 *   2012      Chunhong Yoon
 *
 * This file is part of CrystFEL.
 *
 * CrystFEL is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * CrystFEL is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with CrystFEL.  If not, see <http://www.gnu.org/licenses/>.
 *
 */

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

#include <stdarg.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include <getopt.h>
#include <hdf5.h>
#include <gsl/gsl_errno.h>
#include <pthread.h>
#include <sys/wait.h>
#include <fcntl.h>
#include <signal.h>

#ifdef HAVE_CLOCK_GETTIME
#include <time.h>
#else
#include <sys/time.h>
#endif

#include "utils.h"
#include "hdf5-file.h"
#include "index.h"
#include "peaks.h"
#include "detector.h"
#include "filters.h"
#include "thread-pool.h"
#include "beam-parameters.h"
#include "geometry.h"
#include "stream.h"
#include "reflist-utils.h"

#include "im-sandbox.h"


/* Write statistics at APPROXIMATELY this interval */
#define STATS_EVERY_N_SECONDS (5)


struct sandbox
{
	pthread_mutex_t lock;

	int n_indexable;
	int n_processed;
	int n_indexable_last_stats;
	int n_processed_last_stats;
	int t_last_stats;

	struct index_args *iargs;

	int n_proc;
	pid_t *pids;
	FILE *ofh;
	FILE **fhs;

	int *running;
	FILE **result_fhs;
	int *filename_pipes;
	int *stream_pipe_read;
	int *stream_pipe_write;
	char **last_filename;
};


/* Horrible global variable for signal handler */
int signal_pipe[2];


static void lock_sandbox(struct sandbox *sb)
{
	pthread_mutex_lock(&sb->lock);
}


static void unlock_sandbox(struct sandbox *sb)
{
	pthread_mutex_unlock(&sb->lock);
}


static char *get_pattern(FILE *fh, char **use_this_one_instead,
                         int config_basename, const char *prefix)
{
	char *line;
	char *filename;

	do {

		/* Get the next filename */
		if ( *use_this_one_instead != NULL ) {

			line = *use_this_one_instead;
			*use_this_one_instead = NULL;

		} else {

			char *rval;

			line = malloc(1024*sizeof(char));
			rval = fgets(line, 1023, fh);
			if ( rval == NULL ) {
				free(line);
				return NULL;
			}

		}

		chomp(line);

	} while ( strlen(line) == 0 );

	if ( config_basename ) {
		char *tmp;
		tmp = safe_basename(line);
		free(line);
		line = tmp;
	}

	filename = malloc(strlen(prefix)+strlen(line)+1);

	snprintf(filename, 1023, "%s%s", prefix, line);

	free(line);

	return filename;
}


static void process_image(const struct index_args *iargs,
                          struct pattern_args *pargs, FILE *ofh,
                          int cookie)
{
	float *data_for_measurement;
	size_t data_size;
	UnitCell *cell = iargs->cell;
	int config_cmfilter = iargs->config_cmfilter;
	int config_noisefilter = iargs->config_noisefilter;
	int config_verbose = iargs->config_verbose;
	IndexingMethod *indm = iargs->indm;
	struct beam_params *beam = iargs->beam;
	int r, check;
	struct hdfile *hdfile;
	struct image image;

	image.features = NULL;
	image.data = NULL;
	image.flags = NULL;
	image.indexed_cell = NULL;
	image.det = copy_geom(iargs->det);
	image.copyme = iargs->copyme;
	image.reflections = NULL;
	image.id = cookie;
	image.filename = pargs->filename;
	image.beam = beam;

	hdfile = hdfile_open(image.filename);
	if ( hdfile == NULL ) return;

	r = hdfile_set_first_image(hdfile, "/");
	if ( r ) {
		ERROR("Couldn't select first path\n");
		hdfile_close(hdfile);
		return;
	}

	check = hdf5_read(hdfile, &image, 1);
	if ( check ) {
		hdfile_close(hdfile);
		return;
	}

	if ( (image.width != image.det->max_fs + 1 )
	  || (image.height != image.det->max_ss + 1))
	{
		ERROR("Image size doesn't match geometry size"
			" - rejecting image.\n");
		ERROR("Image size: %i,%i.  Geometry size: %i,%i\n",
		image.width, image.height,
		image.det->max_fs + 1, image.det->max_ss + 1);
		hdfile_close(hdfile);
		free_detector_geometry(image.det);
		return;
	}

	if ( image.lambda < 0.0 ) {
		if ( beam != NULL ) {
			ERROR("Using nominal photon energy of %.2f eV\n",
			beam->photon_energy);
			image.lambda = ph_en_to_lambda(
			eV_to_J(beam->photon_energy));
		} else {
			ERROR("No wavelength in file, so you need to give "
				"a beam parameters file with -b.\n");
			hdfile_close(hdfile);
			free_detector_geometry(image.det);
			return;
		}
	}
	fill_in_values(image.det, hdfile);

	if ( config_cmfilter ) {
		filter_cm(&image);
	}

	/* Take snapshot of image after CM subtraction but before
	 * the aggressive noise filter. */
	data_size = image.width * image.height * sizeof(float);
	data_for_measurement = malloc(data_size);

	if ( config_noisefilter ) {
		filter_noise(&image, data_for_measurement);
	} else {
		memcpy(data_for_measurement, image.data, data_size);
	}

	switch ( iargs->peaks ) {

		case PEAK_HDF5:
		// Get peaks from HDF5
		if (get_peaks(&image, hdfile,
			iargs->hdf5_peak_path)) {
			ERROR("Failed to get peaks from HDF5 file.\n");
		}
		break;

		case PEAK_ZAEF:
		search_peaks(&image, iargs->threshold,
		             iargs->min_gradient, iargs->min_snr,
		             iargs->ir_inn, iargs->ir_mid, iargs->ir_out);
		break;

	}

	/* Get rid of noise-filtered version at this point
	 * - it was strictly for the purposes of peak detection. */
	free(image.data);
	image.data = data_for_measurement;

	/* Calculate orientation matrix (by magic) */
	image.div = beam->divergence;
	image.bw = beam->bandwidth;
	image.profile_radius = 0.0001e9;

	index_pattern(&image, cell, indm, iargs->cellr,
	              config_verbose, iargs->ipriv,
	              iargs->config_insane, iargs->tols);

	if ( image.indexed_cell != NULL ) {
		pargs->indexable = 1;
		image.reflections = find_intersections(&image,
				image.indexed_cell);
		if (image.reflections != NULL) {
			integrate_reflections(&image,
			                      iargs->config_closer,
			                      iargs->config_bgsub,
			                      iargs->min_int_snr,
			                      iargs->ir_inn,
			                      iargs->ir_mid,
			                      iargs->ir_out);
		}
	} else {
		image.reflections = NULL;
	}

	write_chunk(ofh, &image, hdfile, iargs->stream_flags);
	fprintf(ofh, "END\n");
	fflush(ofh);

	/* Only free cell if found */
	cell_free(image.indexed_cell);

	reflist_free(image.reflections);
	free(image.data);
	if ( image.flags != NULL ) free(image.flags);
	image_feature_list_free(image.features);
	hdfile_close(hdfile);
	free_detector_geometry(image.det);
}


static void run_work(const struct index_args *iargs,
                     int filename_pipe, int results_pipe, FILE *ofh,
                     int cookie)
{
	int allDone = 0;
	FILE *fh;
	int w;

	fh = fdopen(filename_pipe, "r");
	if ( fh == NULL ) {
		ERROR("Failed to fdopen() the filename pipe!\n");
		return;
	}

	w = write(results_pipe, "\n", 1);
	if ( w < 0 ) {
		ERROR("Failed to send request for first filename.\n");
	}

	while ( !allDone ) {

		struct pattern_args pargs;
		int  c;
		char *line;
		char *rval;
		char buf[1024];

		line = malloc(1024*sizeof(char));
		rval = fgets(line, 1023, fh);
		if ( rval == NULL ) {

			ERROR("Read error!\n");
			free(line);
			allDone = 1;
			continue;

		}

		chomp(line);

		if ( strlen(line) == 0 ) {

			allDone = 1;

		} else {

			pargs.filename = line;
			pargs.indexable = 0;

			process_image(iargs, &pargs, ofh, cookie);

			/* Request another image */
			c = sprintf(buf, "%i\n", pargs.indexable);
			w = write(results_pipe, buf, c);
			if ( w < 0 ) {
				ERROR("write P0\n");
			}

		}

		free(line);

	}

	cleanup_indexing(iargs->ipriv);
	free(iargs->indm);
	free(iargs->ipriv);
	free_detector_geometry(iargs->det);
	free(iargs->beam);
	free(iargs->element);
	free(iargs->hdf5_peak_path);
	free_copy_hdf5_field_list(iargs->copyme);
	cell_free(iargs->cell);
	fclose(fh);
}


#ifdef HAVE_CLOCK_GETTIME

static time_t get_monotonic_seconds()
{
	struct timespec tp;
	clock_gettime(CLOCK_MONOTONIC, &tp);
	return tp.tv_sec;
}

#else

/* Fallback version of the above.  The time according to gettimeofday() is not
 * monotonic, so measuring intervals based on it will screw up if there's a
 * timezone change (e.g. daylight savings) while the program is running. */
static time_t get_monotonic_seconds()
{
	struct timeval tp;
	gettimeofday(&tp, NULL);
	return tp.tv_sec;
}

#endif

static int pump_chunk(FILE *fh, FILE *ofh)
{
	int chunk_started = 0;
	int chunk_finished = 0;

	do {

		char line[1024];
		char *rval;

		rval = fgets(line, 1024, fh);
		if ( rval == NULL ) {

			if ( feof(fh) ) {
				/* Process died */
				if ( chunk_started ) {
					ERROR("EOF during chunk!\n");
					fprintf(ofh, "Chunk is unfinished!\n");
				}
				return 1;
			} else {
				ERROR("fgets() failed: %s\n", strerror(errno));
			}
			chunk_finished = 1;
			continue;

		}

		if ( strcmp(line, "END\n") == 0 ) {
			chunk_finished = 1;
		} else {
			chunk_started = 1;
			fprintf(ofh, "%s", line);
		}

	} while ( !chunk_finished );

	return 0;
}


static void *run_reader(void *sbv)
{
	struct sandbox *sb = sbv;
	int done = 0;

	while ( !done ) {

		int r, i;
		struct timeval tv;
		fd_set fds;
		int fdmax;

		tv.tv_sec = 5;
		tv.tv_usec = 0;

		FD_ZERO(&fds);
		fdmax = 0;
		lock_sandbox(sb);
		for ( i=0; i<sb->n_proc; i++ ) {

			int fd;

			if ( !sb->running[i] ) continue;

			fd = sb->stream_pipe_read[i];

			FD_SET(fd, &fds);
			if ( fd > fdmax ) fdmax = fd;

		}

		unlock_sandbox(sb);

		r = select(fdmax+1, &fds, NULL, NULL, &tv);

		if ( r == -1 ) {
			if ( errno != EINTR ) {
				ERROR("select() failed: %s\n", strerror(errno));
			} /* Otherwise no big deal */
			continue;
		}

		if ( r == 0 ) continue; /* Nothing this time.  Try again */

		lock_sandbox(sb);
		for ( i=0; i<sb->n_proc; i++ ) {

			if ( !sb->running[i] ) continue;

			if ( !FD_ISSET(sb->stream_pipe_read[i], &fds) ) continue;

			if ( pump_chunk(sb->fhs[i], sb->ofh) ) {
				sb->running[i] = 0;
			}

		}

		done = 1;
		for ( i=0; i<sb->n_proc; i++ ) {
			if ( sb->running[i] ) done = 0;
		}
		unlock_sandbox(sb);

	}

	return NULL;
}


static void start_worker_process(struct sandbox *sb, int slot)
{
	pid_t p;
	int filename_pipe[2];
	int result_pipe[2];

	if ( pipe(filename_pipe) == - 1 ) {
		ERROR("pipe() failed!\n");
		return;
	}

	if ( pipe(result_pipe) == - 1 ) {
		ERROR("pipe() failed!\n");
		return;
	}

	p = fork();
	if ( p == -1 ) {
		ERROR("fork() failed!\n");
		return;
	}

	if ( p == 0 ) {

		FILE *sfh;
		int j;
		struct sigaction sa;
		int r;

		/* First, disconnect the signal handler */
		sa.sa_flags = 0;
		sigemptyset(&sa.sa_mask);
		sa.sa_handler = SIG_DFL;
		r = sigaction(SIGCHLD, &sa, NULL);
		if ( r == -1 ) {
			ERROR("Failed to set signal handler!\n");
			return;
		}

		/* Free resources which will not be needed by worker */
		for ( j=0; j<sb->n_proc; j++ ) {
			if ( (j != slot) && (sb->running[j]) ) {
				close(sb->stream_pipe_write[j]);
			}
		}
		for ( j=0; j<sb->n_proc; j++ ) {
			if ( (j != slot) && (sb->running[j]) ) {
				fclose(sb->result_fhs[j]);
				close(sb->filename_pipes[j]);
			}
		}
		free(sb->filename_pipes);
		free(sb->result_fhs);
		free(sb->pids);
		/* Also prefix, use_this_one_instead and fh */

		/* Child process gets the 'read' end of the filename
		 * pipe, and the 'write' end of the result pipe. */
		close(filename_pipe[1]);
		close(result_pipe[0]);

		sfh = fdopen(sb->stream_pipe_write[slot], "w");
		run_work(sb->iargs, filename_pipe[0], result_pipe[1],
		         sfh, slot);
		fclose(sfh);

		//close(filename_pipe[0]);
		close(result_pipe[1]);

		exit(0);

	}

	/* Parent process gets the 'write' end of the filename pipe
	 * and the 'read' end of the result pipe. */
	sb->pids[slot] = p;
	sb->running[slot] = 1;
	close(filename_pipe[0]);
	close(result_pipe[1]);
	sb->filename_pipes[slot] = filename_pipe[1];
	sb->fhs[slot] = fdopen(sb->stream_pipe_read[slot], "r");
	if ( sb->fhs[slot] == NULL ) {
		ERROR("Couldn't fdopen() stream!\n");
		return;
	}

	sb->result_fhs[slot] = fdopen(result_pipe[0], "r");
	if ( sb->result_fhs[slot] == NULL ) {
		ERROR("fdopen() failed.\n");
		return;
	}
}


static void signal_handler(int sig, siginfo_t *si, void *uc_v)
{
	write(signal_pipe[1], "\n", 1);
}


static void handle_zombie(struct sandbox *sb)
{
	int i;

	lock_sandbox(sb);
	for ( i=0; i<sb->n_proc; i++ ) {

		int status, p;

		if ( !sb->running[i] ) continue;

		p = waitpid(sb->pids[i], &status, WNOHANG);

		if ( p == -1 ) {
			ERROR("waitpid() failed.\n");
			continue;
		}

		if ( p == sb->pids[i] ) {

			sb->running[i] = 0;

			if ( WIFEXITED(status) ) {
				STATUS("Worker %i exited normally.\n", i);
				continue;
			}

			if ( WIFSIGNALED(status) ) {
				STATUS("Worker %i was killed by signal %i\n",
				       i, WTERMSIG(status));
				STATUS("Last filename was: %s\n",
				       sb->last_filename[i]);
				start_worker_process(sb, i);
			}

		}

	}
	unlock_sandbox(sb);
}


void create_sandbox(struct index_args *iargs, int n_proc, char *prefix,
                    int config_basename, FILE *fh, char *use_this_one_instead,
                    FILE *ofh)
{
	int i;
	int allDone;
	struct sigaction sa;
	int r;
	pthread_t reader_thread;
	struct sandbox *sb;

	sb = calloc(1, sizeof(struct sandbox));
	if ( sb == NULL ) {
		ERROR("Couldn't allocate memory for sandbox.\n");
		return;
	}

	sb->n_indexable = 0;
	sb->n_processed = 0;
	sb->n_indexable_last_stats = 0;
	sb->n_processed_last_stats = 0;
	sb->t_last_stats = get_monotonic_seconds();
	sb->n_proc = n_proc;
	sb->ofh = ofh;
	sb->iargs = iargs;

	pthread_mutex_init(&sb->lock, NULL);

	sb->stream_pipe_read = calloc(n_proc, sizeof(int));
	sb->stream_pipe_write = calloc(n_proc, sizeof(int));
	if ( sb->stream_pipe_read == NULL ) {
		ERROR("Couldn't allocate memory for pipes.\n");
		return;
	}
	if ( sb->stream_pipe_write == NULL ) {
		ERROR("Couldn't allocate memory for pipes.\n");
		return;
	}

	for ( i=0; i<n_proc; i++ ) {

		int stream_pipe[2];

		if ( pipe(stream_pipe) == - 1 ) {
			ERROR("pipe() failed!\n");
			return;
		}

		sb->stream_pipe_read[i] = stream_pipe[0];
		sb->stream_pipe_write[i] = stream_pipe[1];

	}

	lock_sandbox(sb);
	sb->filename_pipes = calloc(n_proc, sizeof(int));
	sb->result_fhs = calloc(n_proc, sizeof(FILE *));
	sb->pids = calloc(n_proc, sizeof(pid_t));
	sb->running = calloc(n_proc, sizeof(int));
	sb->fhs = calloc(sb->n_proc, sizeof(FILE *));
	if ( sb->filename_pipes == NULL ) {
		ERROR("Couldn't allocate memory for pipes.\n");
		return;
	}
	if ( sb->result_fhs == NULL ) {
		ERROR("Couldn't allocate memory for pipe file handles.\n");
		return;
	}
	if ( sb->pids == NULL ) {
		ERROR("Couldn't allocate memory for PIDs.\n");
		return;
	}
	if ( sb->running == NULL ) {
		ERROR("Couldn't allocate memory for process flags.\n");
		return;
	}

	sb->last_filename = calloc(n_proc, sizeof(char *));
	if ( sb->last_filename == NULL ) {
		ERROR("Couldn't allocate memory for last filename list.\n");
		return;
	}
	if ( sb->fhs == NULL ) {
		ERROR("Couldn't allocate memory for file handles!\n");
		return;
	}
	unlock_sandbox(sb);

	if ( pthread_create(&reader_thread, NULL, run_reader, (void *)sb) ) {
		ERROR("Failed to create reader thread.\n");
		return;
	}

	if ( pipe(signal_pipe) == -1 ) {
		ERROR("Failed to create signal pipe.\n");
		return;
	}

	/* Set up signal handler to take action if any children die */
	sa.sa_flags = SA_SIGINFO | SA_NOCLDSTOP;
	sigemptyset(&sa.sa_mask);
	sa.sa_sigaction = signal_handler;
	r = sigaction(SIGCHLD, &sa, NULL);
	if ( r == -1 ) {
		ERROR("Failed to set signal handler!\n");
		return;
	}

	/* Fork the right number of times */
	lock_sandbox(sb);
	for ( i=0; i<n_proc; i++ ) {
		start_worker_process(sb, i);
	}
	unlock_sandbox(sb);

	allDone = 0;
	while ( !allDone ) {

		int r, i;
		struct timeval tv;
		fd_set fds;
		double tNow;
		int fdmax;

		tv.tv_sec = 1;
		tv.tv_usec = 0;

		FD_ZERO(&fds);
		fdmax = 0;
		lock_sandbox(sb);
		for ( i=0; i<n_proc; i++ ) {

			int fd;

			if ( !sb->running[i] ) {
				continue;
			}

			fd = fileno(sb->result_fhs[i]);
			FD_SET(fd, &fds);
			if ( fd > fdmax ) fdmax = fd;

		}
		unlock_sandbox(sb);

		FD_SET(signal_pipe[0], &fds);
		if ( signal_pipe[0] > fdmax ) fdmax = signal_pipe[0];

		r = select(fdmax+1, &fds, NULL, NULL, &tv);
		if ( r == -1 ) {
			if ( errno != EINTR ) {
				ERROR("select() failed: %s\n", strerror(errno));
			}
			continue;
		}

		if ( r == 0 ) continue; /* No progress this time.  Try again */

		if ( FD_ISSET(signal_pipe[0], &fds) ) {

			char d;
			read(signal_pipe[0], &d, 1);
			handle_zombie(sb);

		}

		lock_sandbox(sb);
		for ( i=0; i<n_proc; i++ ) {

			char *nextImage;
			char results[1024];
			char *rval;
			int fd;
			int n;
			char *eptr;

			if ( !sb->running[i] ) {
				continue;
			}

			fd = fileno(sb->result_fhs[i]);
			if ( !FD_ISSET(fd, &fds) ) {
				continue;
			}

			rval = fgets(results, 1024, sb->result_fhs[i]);
			if ( rval == NULL ) {
				if ( !feof(sb->result_fhs[i]) ) {
					ERROR("fgets() failed: %s\n",
					      strerror(errno));
				}
				continue;
			}

			chomp(results);

			n = strtol(results, &eptr, 10);
			if ( eptr == results ) {
				if ( strlen(results) > 0 ) {
					ERROR("Invalid result '%s'\n", results);
				}
			} else {
				sb->n_indexable += atoi(results);
				sb->n_processed++;
			}

			/* Send next filename */
			nextImage = get_pattern(fh, &use_this_one_instead,
	                                        config_basename, prefix);

			free(sb->last_filename[i]);
			sb->last_filename[i] = nextImage;

			if ( nextImage == NULL ) {
				/* No more images */
				r = write(sb->filename_pipes[i], "\n", 1);
				if ( r < 0 ) {
					ERROR("Write pipe\n");
				}
			} else {
				r = write(sb->filename_pipes[i], nextImage,
				          strlen(nextImage));
				r -= write(sb->filename_pipes[i], "\n", 1);
				if ( r < 0 ) {
					ERROR("write pipe\n");
				}
			}

		}

		/* Update progress */
		tNow = get_monotonic_seconds();
		if ( tNow >= sb->t_last_stats+STATS_EVERY_N_SECONDS ) {

			STATUS("%i out of %i indexed so far,"
			       " %i out of %i since the last message.\n",
			       sb->n_indexable, sb->n_processed,
			       sb->n_indexable - sb->n_indexable_last_stats,
			       sb->n_processed - sb->n_processed_last_stats);

			sb->n_indexable_last_stats = sb->n_indexable;
			sb->n_processed_last_stats = sb->n_processed;
			sb->t_last_stats = tNow;

		}

		allDone = 1;
		for ( i=0; i<n_proc; i++ ) {
			if ( sb->running[i] ) allDone = 0;
		}

		unlock_sandbox(sb);

	}

	fclose(fh);

	pthread_mutex_destroy(&sb->lock);

	for ( i=0; i<n_proc; i++ ) {
		int status;
		waitpid(sb->pids[i], &status, 0);
	}

	for ( i=0; i<n_proc; i++ ) {
		close(sb->filename_pipes[i]);
		fclose(sb->result_fhs[i]);
	}

	for ( i=0; i<sb->n_proc; i++ ) {
		fclose(sb->fhs[i]);
	}
	free(sb->fhs);
	free(sb->filename_pipes);
	free(sb->result_fhs);
	free(sb->pids);
	free(sb->running);

	if ( ofh != stdout ) fclose(ofh);

	STATUS("There were %i images, of which %i could be indexed.\n",
	       sb->n_processed, sb->n_indexable);

}