2 Copyright (C) 2001, 2002 Free Software Foundation, Inc.
4 This file is part of GNU Wget.
6 GNU Wget is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2 of the License, or
9 (at your option) any later version.
11 GNU Wget is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with Wget; if not, write to the Free Software
18 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
20 In addition, as a special exception, the Free Software Foundation
21 gives permission to link the code of its release of Wget with the
22 OpenSSL project's "OpenSSL" library (or with modified versions of it
23 that use the same license as the "OpenSSL" library), and distribute
24 the linked executables. You must obey the GNU General Public License
25 in all respects for all of the code used other than "OpenSSL". If you
26 modify this file, you may extend this exception to your version of the
27 file, but you are not obligated to do so. If you do not wish to do
28 so, delete this exception statement from your version. */
46 struct progress_implementation {
49 void *(*create) (wgint, wgint);
50 void (*update) (void *, wgint, double);
51 void (*finish) (void *, double);
52 void (*set_params) (const char *);
55 /* Necessary forward declarations. */
57 static void *dot_create (wgint, wgint);
58 static void dot_update (void *, wgint, double);
59 static void dot_finish (void *, double);
60 static void dot_set_params (const char *);
62 static void *bar_create (wgint, wgint);
63 static void bar_update (void *, wgint, double);
64 static void bar_finish (void *, double);
65 static void bar_set_params (const char *);
67 static struct progress_implementation implementations[] = {
68 { "dot", 0, dot_create, dot_update, dot_finish, dot_set_params },
69 { "bar", 1, bar_create, bar_update, bar_finish, bar_set_params }
71 static struct progress_implementation *current_impl;
72 static int current_impl_locked;
74 /* Progress implementation used by default. Can be overriden in
75 wgetrc or by the fallback one. */
77 #define DEFAULT_PROGRESS_IMPLEMENTATION "bar"
79 /* Fallnback progress implementation should be something that works
80 under all display types. If you put something other than "dot"
81 here, remember that bar_set_params tries to switch to this if we're
82 not running on a TTY. So changing this to "bar" could cause
85 #define FALLBACK_PROGRESS_IMPLEMENTATION "dot"
87 /* Return true if NAME names a valid progress bar implementation. The
88 characters after the first : will be ignored. */
91 valid_progress_implementation_p (const char *name)
94 struct progress_implementation *pi = implementations;
95 char *colon = strchr (name, ':');
96 int namelen = colon ? colon - name : strlen (name);
98 for (i = 0; i < countof (implementations); i++, pi++)
99 if (!strncmp (pi->name, name, namelen))
104 /* Set the progress implementation to NAME. */
107 set_progress_implementation (const char *name)
110 struct progress_implementation *pi = implementations;
114 name = DEFAULT_PROGRESS_IMPLEMENTATION;
116 colon = strchr (name, ':');
117 namelen = colon ? colon - name : strlen (name);
119 for (i = 0; i < countof (implementations); i++, pi++)
120 if (!strncmp (pi->name, name, namelen))
123 current_impl_locked = 0;
126 /* We call pi->set_params even if colon is NULL because we
127 want to give the implementation a chance to set up some
128 things it needs to run. */
132 pi->set_params (colon);
138 static int output_redirected;
141 progress_schedule_redirect (void)
143 output_redirected = 1;
146 /* Create a progress gauge. INITIAL is the number of bytes the
147 download starts from (zero if the download starts from scratch).
148 TOTAL is the expected total number of bytes in this download. If
149 TOTAL is zero, it means that the download size is not known in
153 progress_create (wgint initial, wgint total)
155 /* Check if the log status has changed under our feet. */
156 if (output_redirected)
158 if (!current_impl_locked)
159 set_progress_implementation (FALLBACK_PROGRESS_IMPLEMENTATION);
160 output_redirected = 0;
163 return current_impl->create (initial, total);
166 /* Return true if the progress gauge is "interactive", i.e. if it can
167 profit from being called regularly even in absence of data. The
168 progress bar is interactive because it regularly updates the ETA
169 and current update. */
172 progress_interactive_p (void *progress)
174 return current_impl->interactive;
177 /* Inform the progress gauge of newly received bytes. DLTIME is the
178 time in milliseconds since the beginning of the download. */
181 progress_update (void *progress, wgint howmuch, double dltime)
183 current_impl->update (progress, howmuch, dltime);
186 /* Tell the progress gauge to clean up. Calling this will free the
187 PROGRESS object, the further use of which is not allowed. */
190 progress_finish (void *progress, double dltime)
192 current_impl->finish (progress, dltime);
197 struct dot_progress {
198 wgint initial_length; /* how many bytes have been downloaded
200 wgint total_length; /* expected total byte count when the
205 int rows; /* number of rows printed so far */
206 int dots; /* number of dots printed in this row */
207 double last_timer_value;
210 /* Dot-progress backend for progress_create. */
213 dot_create (wgint initial, wgint total)
215 struct dot_progress *dp = xnew0 (struct dot_progress);
216 dp->initial_length = initial;
217 dp->total_length = total;
219 if (dp->initial_length)
221 int dot_bytes = opt.dot_bytes;
222 wgint row_bytes = opt.dot_bytes * opt.dots_in_line;
224 int remainder = (int) (dp->initial_length % row_bytes);
225 wgint skipped = dp->initial_length - remainder;
229 int skipped_k = (int) (skipped / 1024); /* skipped amount in K */
230 int skipped_k_len = numdigit (skipped_k);
231 if (skipped_k_len < 5)
234 /* Align the [ skipping ... ] line with the dots. To do
235 that, insert the number of spaces equal to the number of
236 digits in the skipped amount in K. */
237 logprintf (LOG_VERBOSE, _("\n%*s[ skipping %dK ]"),
238 2 + skipped_k_len, "", skipped_k);
241 logprintf (LOG_VERBOSE, "\n%5ldK", (long) (skipped / 1024));
242 for (; remainder >= dot_bytes; remainder -= dot_bytes)
244 if (dp->dots % opt.dot_spacing == 0)
245 logputs (LOG_VERBOSE, " ");
246 logputs (LOG_VERBOSE, ",");
249 assert (dp->dots < opt.dots_in_line);
251 dp->accumulated = remainder;
252 dp->rows = skipped / row_bytes;
259 print_percentage (wgint bytes, wgint expected)
261 int percentage = (int)(100.0 * bytes / expected);
262 logprintf (LOG_VERBOSE, "%3d%%", percentage);
266 print_download_speed (struct dot_progress *dp, wgint bytes, double dltime)
268 logprintf (LOG_VERBOSE, " %s",
269 retr_rate (bytes, dltime - dp->last_timer_value, 1));
270 dp->last_timer_value = dltime;
273 /* Dot-progress backend for progress_update. */
276 dot_update (void *progress, wgint howmuch, double dltime)
278 struct dot_progress *dp = progress;
279 int dot_bytes = opt.dot_bytes;
280 wgint row_bytes = opt.dot_bytes * opt.dots_in_line;
282 log_set_flush (false);
284 dp->accumulated += howmuch;
285 for (; dp->accumulated >= dot_bytes; dp->accumulated -= dot_bytes)
288 logprintf (LOG_VERBOSE, "\n%5ldK", (long) (dp->rows * row_bytes / 1024));
290 if (dp->dots % opt.dot_spacing == 0)
291 logputs (LOG_VERBOSE, " ");
292 logputs (LOG_VERBOSE, ".");
295 if (dp->dots >= opt.dots_in_line)
297 wgint row_qty = row_bytes;
298 if (dp->rows == dp->initial_length / row_bytes)
299 row_qty -= dp->initial_length % row_bytes;
304 if (dp->total_length)
305 print_percentage (dp->rows * row_bytes, dp->total_length);
306 print_download_speed (dp, row_qty, dltime);
310 log_set_flush (true);
313 /* Dot-progress backend for progress_finish. */
316 dot_finish (void *progress, double dltime)
318 struct dot_progress *dp = progress;
319 int dot_bytes = opt.dot_bytes;
320 wgint row_bytes = opt.dot_bytes * opt.dots_in_line;
323 log_set_flush (false);
326 logprintf (LOG_VERBOSE, "\n%5ldK", (long) (dp->rows * row_bytes / 1024));
327 for (i = dp->dots; i < opt.dots_in_line; i++)
329 if (i % opt.dot_spacing == 0)
330 logputs (LOG_VERBOSE, " ");
331 logputs (LOG_VERBOSE, " ");
333 if (dp->total_length)
335 print_percentage (dp->rows * row_bytes
336 + dp->dots * dot_bytes
342 wgint row_qty = dp->dots * dot_bytes + dp->accumulated;
343 if (dp->rows == dp->initial_length / row_bytes)
344 row_qty -= dp->initial_length % row_bytes;
345 print_download_speed (dp, row_qty, dltime);
348 logputs (LOG_VERBOSE, "\n\n");
349 log_set_flush (false);
354 /* This function interprets the progress "parameters". For example,
355 if Wget is invoked with --progress=dot:mega, it will set the
356 "dot-style" to "mega". Valid styles are default, binary, mega, and
360 dot_set_params (const char *params)
362 if (!params || !*params)
363 params = opt.dot_style;
368 /* We use this to set the retrieval style. */
369 if (!strcasecmp (params, "default"))
371 /* Default style: 1K dots, 10 dots in a cluster, 50 dots in a
373 opt.dot_bytes = 1024;
374 opt.dot_spacing = 10;
375 opt.dots_in_line = 50;
377 else if (!strcasecmp (params, "binary"))
379 /* "Binary" retrieval: 8K dots, 16 dots in a cluster, 48 dots
381 opt.dot_bytes = 8192;
382 opt.dot_spacing = 16;
383 opt.dots_in_line = 48;
385 else if (!strcasecmp (params, "mega"))
387 /* "Mega" retrieval, for retrieving very long files; each dot is
388 64K, 8 dots in a cluster, 6 clusters (3M) in a line. */
389 opt.dot_bytes = 65536L;
391 opt.dots_in_line = 48;
393 else if (!strcasecmp (params, "giga"))
395 /* "Giga" retrieval, for retrieving very very *very* long files;
396 each dot is 1M, 8 dots in a cluster, 4 clusters (32M) in a
398 opt.dot_bytes = (1L << 20);
400 opt.dots_in_line = 32;
404 _("Invalid dot style specification `%s'; leaving unchanged.\n"),
408 /* "Thermometer" (bar) progress. */
410 /* Assumed screen width if we can't find the real value. */
411 #define DEFAULT_SCREEN_WIDTH 80
413 /* Minimum screen width we'll try to work with. If this is too small,
414 create_image will overflow the buffer. */
415 #define MINIMUM_SCREEN_WIDTH 45
417 /* The last known screen width. This can be updated by the code that
418 detects that SIGWINCH was received (but it's never updated from the
420 static int screen_width;
422 /* A flag that, when set, means SIGWINCH was received. */
423 static volatile sig_atomic_t received_sigwinch;
425 /* Size of the download speed history ring. */
426 #define DLSPEED_HISTORY_SIZE 20
428 /* The minimum time length of a history sample. By default, each
429 sample is at least 150ms long, which means that, over the course of
430 20 samples, "current" download speed spans at least 3s into the
432 #define DLSPEED_SAMPLE_MIN 150
434 /* The time after which the download starts to be considered
435 "stalled", i.e. the current bandwidth is not printed and the recent
436 download speeds are scratched. */
437 #define STALL_START_TIME 5000
439 struct bar_progress {
440 wgint initial_length; /* how many bytes have been downloaded
442 wgint total_length; /* expected total byte count when the
444 wgint count; /* bytes downloaded so far */
446 double last_screen_update; /* time of the last screen update,
447 measured since the beginning of
450 int width; /* screen width we're using at the
451 time the progress gauge was
452 created. this is different from
453 the screen_width global variable in
454 that the latter can be changed by a
456 char *buffer; /* buffer where the bar "image" is
458 int tick; /* counter used for drawing the
459 progress bar where the total size
462 /* The following variables (kept in a struct for namespace reasons)
463 keep track of recent download speeds. See bar_update() for
465 struct bar_progress_hist {
467 wgint times[DLSPEED_HISTORY_SIZE];
468 wgint bytes[DLSPEED_HISTORY_SIZE];
470 /* The sum of times and bytes respectively, maintained for
476 double recent_start; /* timestamp of beginning of current
478 wgint recent_bytes; /* bytes downloaded so far. */
480 bool stalled; /* set when no data arrives for longer
481 than STALL_START_TIME, then reset
482 when new data arrives. */
484 /* create_image() uses these to make sure that ETA information
486 double last_eta_time; /* time of the last update to download
487 speed and ETA, measured since the
488 beginning of download. */
489 wgint last_eta_value;
492 static void create_image (struct bar_progress *, double);
493 static void display_image (char *);
496 bar_create (wgint initial, wgint total)
498 struct bar_progress *bp = xnew0 (struct bar_progress);
500 /* In theory, our callers should take care of this pathological
501 case, but it can sometimes happen. */
505 bp->initial_length = initial;
506 bp->total_length = total;
508 /* Initialize screen_width if this hasn't been done or if it might
509 have changed, as indicated by receiving SIGWINCH. */
510 if (!screen_width || received_sigwinch)
512 screen_width = determine_screen_width ();
514 screen_width = DEFAULT_SCREEN_WIDTH;
515 else if (screen_width < MINIMUM_SCREEN_WIDTH)
516 screen_width = MINIMUM_SCREEN_WIDTH;
517 received_sigwinch = 0;
520 /* - 1 because we don't want to use the last screen column. */
521 bp->width = screen_width - 1;
522 /* + 1 for the terminating zero. */
523 bp->buffer = xmalloc (bp->width + 1);
525 logputs (LOG_VERBOSE, "\n");
527 create_image (bp, 0);
528 display_image (bp->buffer);
533 static void update_speed_ring (struct bar_progress *, wgint, double);
536 bar_update (void *progress, wgint howmuch, double dltime)
538 struct bar_progress *bp = progress;
539 bool force_screen_update = false;
541 bp->count += howmuch;
542 if (bp->total_length > 0
543 && bp->count + bp->initial_length > bp->total_length)
544 /* We could be downloading more than total_length, e.g. when the
545 server sends an incorrect Content-Length header. In that case,
546 adjust bp->total_length to the new reality, so that the code in
547 create_image() that depends on total size being smaller or
548 equal to the expected size doesn't abort. */
549 bp->total_length = bp->initial_length + bp->count;
551 update_speed_ring (bp, howmuch, dltime);
553 /* If SIGWINCH (the window size change signal) been received,
554 determine the new screen size and update the screen. */
555 if (received_sigwinch)
557 int old_width = screen_width;
558 screen_width = determine_screen_width ();
560 screen_width = DEFAULT_SCREEN_WIDTH;
561 else if (screen_width < MINIMUM_SCREEN_WIDTH)
562 screen_width = MINIMUM_SCREEN_WIDTH;
563 if (screen_width != old_width)
565 bp->width = screen_width - 1;
566 bp->buffer = xrealloc (bp->buffer, bp->width + 1);
567 force_screen_update = true;
569 received_sigwinch = 0;
572 if (dltime - bp->last_screen_update < 200 && !force_screen_update)
573 /* Don't update more often than five times per second. */
576 create_image (bp, dltime);
577 display_image (bp->buffer);
578 bp->last_screen_update = dltime;
582 bar_finish (void *progress, double dltime)
584 struct bar_progress *bp = progress;
586 if (bp->total_length > 0
587 && bp->count + bp->initial_length > bp->total_length)
588 /* See bar_update() for explanation. */
589 bp->total_length = bp->initial_length + bp->count;
591 create_image (bp, dltime);
592 display_image (bp->buffer);
594 logputs (LOG_VERBOSE, "\n\n");
600 /* This code attempts to maintain the notion of a "current" download
601 speed, over the course of no less than 3s. (Shorter intervals
602 produce very erratic results.)
604 To do so, it samples the speed in 150ms intervals and stores the
605 recorded samples in a FIFO history ring. The ring stores no more
606 than 20 intervals, hence the history covers the period of at least
607 three seconds and at most 20 reads into the past. This method
608 should produce reasonable results for downloads ranging from very
611 The idea is that for fast downloads, we get the speed over exactly
612 the last three seconds. For slow downloads (where a network read
613 takes more than 150ms to complete), we get the speed over a larger
614 time period, as large as it takes to complete thirty reads. This
615 is good because slow downloads tend to fluctuate more and a
616 3-second average would be too erratic. */
619 update_speed_ring (struct bar_progress *bp, wgint howmuch, double dltime)
621 struct bar_progress_hist *hist = &bp->hist;
622 double recent_age = dltime - bp->recent_start;
624 /* Update the download count. */
625 bp->recent_bytes += howmuch;
627 /* For very small time intervals, we return after having updated the
628 "recent" download count. When its age reaches or exceeds minimum
629 sample time, it will be recorded in the history ring. */
630 if (recent_age < DLSPEED_SAMPLE_MIN)
635 /* If we're not downloading anything, we might be stalling,
636 i.e. not downloading anything for an extended period of time.
637 Since 0-reads do not enter the history ring, recent_age
638 effectively measures the time since last read. */
639 if (recent_age >= STALL_START_TIME)
641 /* If we're stalling, reset the ring contents because it's
642 stale and because it will make bar_update stop printing
643 the (bogus) current bandwidth. */
646 bp->recent_bytes = 0;
651 /* We now have a non-zero amount of to store to the speed ring. */
653 /* If the stall status was acquired, reset it. */
657 /* "recent_age" includes the the entired stalled period, which
658 could be very long. Don't update the speed ring with that
659 value because the current bandwidth would start too small.
660 Start with an arbitrary (but more reasonable) time value and
665 /* Store "recent" bytes and download time to history ring at the
668 /* To correctly maintain the totals, first invalidate existing data
669 (least recent in time) at this position. */
670 hist->total_time -= hist->times[hist->pos];
671 hist->total_bytes -= hist->bytes[hist->pos];
673 /* Now store the new data and update the totals. */
674 hist->times[hist->pos] = recent_age;
675 hist->bytes[hist->pos] = bp->recent_bytes;
676 hist->total_time += recent_age;
677 hist->total_bytes += bp->recent_bytes;
679 /* Start a new "recent" period. */
680 bp->recent_start = dltime;
681 bp->recent_bytes = 0;
683 /* Advance the current ring position. */
684 if (++hist->pos == DLSPEED_HISTORY_SIZE)
688 /* Sledgehammer check to verify that the totals are accurate. */
691 double sumt = 0, sumb = 0;
692 for (i = 0; i < DLSPEED_HISTORY_SIZE; i++)
694 sumt += hist->times[i];
695 sumb += hist->bytes[i];
697 assert (sumt == hist->total_time);
698 assert (sumb == hist->total_bytes);
703 #define APPEND_LITERAL(s) do { \
704 memcpy (p, s, sizeof (s) - 1); \
705 p += sizeof (s) - 1; \
709 # define MAX(a, b) ((a) >= (b) ? (a) : (b))
713 create_image (struct bar_progress *bp, double dl_total_time)
715 char *p = bp->buffer;
716 wgint size = bp->initial_length + bp->count;
718 char *size_legible = with_thousand_seps (size);
719 int size_legible_len = strlen (size_legible);
721 struct bar_progress_hist *hist = &bp->hist;
723 /* The progress bar should look like this:
724 xx% [=======> ] nn,nnn 12.34K/s ETA 00:00
726 Calculate the geometry. The idea is to assign as much room as
727 possible to the progress bar. The other idea is to never let
728 things "jitter", i.e. pad elements that vary in size so that
729 their variance does not affect the placement of other elements.
730 It would be especially bad for the progress bar to be resized
733 "xx% " or "100%" - percentage - 4 chars
734 "[]" - progress bar decorations - 2 chars
735 " nnn,nnn,nnn" - downloaded bytes - 12 chars or very rarely more
736 " 1012.56K/s" - dl rate - 11 chars
737 " ETA xx:xx:xx" - ETA - 13 chars
739 "=====>..." - progress bar - the rest
741 int dlbytes_size = 1 + MAX (size_legible_len, 11);
742 int progress_size = bp->width - (4 + 2 + dlbytes_size + 11 + 13);
744 if (progress_size < 5)
748 if (bp->total_length > 0)
750 int percentage = (int)(100.0 * size / bp->total_length);
752 assert (percentage <= 100);
754 if (percentage < 100)
755 sprintf (p, "%2d%% ", percentage);
761 APPEND_LITERAL (" ");
763 /* The progress bar: "[====> ]" or "[++==> ]". */
764 if (progress_size && bp->total_length > 0)
766 /* Size of the initial portion. */
767 int insz = (double)bp->initial_length / bp->total_length * progress_size;
769 /* Size of the downloaded portion. */
770 int dlsz = (double)size / bp->total_length * progress_size;
775 assert (dlsz <= progress_size);
776 assert (insz <= dlsz);
781 /* Print the initial portion of the download with '+' chars, the
782 rest with '=' and one '>'. */
783 for (i = 0; i < insz; i++)
788 for (i = 0; i < dlsz - 1; i++)
793 while (p - begin < progress_size)
797 else if (progress_size)
799 /* If we can't draw a real progress bar, then at least show
800 *something* to the user. */
801 int ind = bp->tick % (progress_size * 2 - 6);
804 /* Make the star move in two directions. */
805 if (ind < progress_size - 2)
808 pos = progress_size - (ind - progress_size + 5);
811 for (i = 0; i < progress_size; i++)
813 if (i == pos - 1) *p++ = '<';
814 else if (i == pos ) *p++ = '=';
815 else if (i == pos + 1) *p++ = '>';
825 sprintf (p, " %-11s", with_thousand_seps (size));
829 if (hist->total_time && hist->total_bytes)
831 static const char *short_units[] = { "B/s", "K/s", "M/s", "G/s" };
833 /* Calculate the download speed using the history ring and
834 recent data that hasn't made it to the ring yet. */
835 wgint dlquant = hist->total_bytes + bp->recent_bytes;
836 double dltime = hist->total_time + (dl_total_time - bp->recent_start);
837 double dlspeed = calc_rate (dlquant, dltime, &units);
838 sprintf (p, " %7.2f%s", dlspeed, short_units[units]);
842 APPEND_LITERAL (" --.--K/s");
844 /* " ETA xx:xx:xx"; wait for three seconds before displaying the ETA.
845 That's because the ETA value needs a while to become
847 if (bp->total_length > 0 && bp->count > 0 && dl_total_time > 3000)
850 int eta_hrs, eta_min, eta_sec;
852 /* Don't change the value of ETA more than approximately once
853 per second; doing so would cause flashing without providing
854 any value to the user. */
855 if (bp->total_length != size
856 && bp->last_eta_value != 0
857 && dl_total_time - bp->last_eta_time < 900)
858 eta = bp->last_eta_value;
861 /* Calculate ETA using the average download speed to predict
862 the future speed. If you want to use a speed averaged
863 over a more recent period, replace dl_total_time with
864 hist->total_time and bp->count with hist->total_bytes.
865 I found that doing that results in a very jerky and
866 ultimately unreliable ETA. */
867 double time_sofar = (double)dl_total_time / 1000;
868 wgint bytes_remaining = bp->total_length - size;
869 eta = (wgint) (time_sofar * bytes_remaining / bp->count);
870 bp->last_eta_value = eta;
871 bp->last_eta_time = dl_total_time;
874 eta_hrs = eta / 3600, eta %= 3600;
875 eta_min = eta / 60, eta %= 60;
883 /* Hours not printed: pad with three spaces. */
884 APPEND_LITERAL (" ");
885 sprintf (p, " ETA %02d:%02d", eta_min, eta_sec);
890 /* Hours printed with one digit: pad with one space. */
892 sprintf (p, " ETA %d:%02d:%02d", eta_hrs, eta_min, eta_sec);
896 else if (bp->total_length > 0)
899 APPEND_LITERAL (" ");
902 assert (p - bp->buffer <= bp->width);
904 while (p < bp->buffer + bp->width)
909 /* Print the contents of the buffer as a one-line ASCII "image" so
910 that it can be overwritten next time. */
913 display_image (char *buf)
915 bool old = log_set_save_context (false);
916 logputs (LOG_VERBOSE, "\r");
917 logputs (LOG_VERBOSE, buf);
918 log_set_save_context (old);
922 bar_set_params (const char *params)
924 char *term = getenv ("TERM");
927 && 0 == strcmp (params, "force"))
928 current_impl_locked = 1;
932 /* The progress bar doesn't make sense if the output is not a
933 TTY -- when logging to file, it is better to review the
935 || !isatty (fileno (stderr))
937 /* Normally we don't depend on terminal type because the
938 progress bar only uses ^M to move the cursor to the
939 beginning of line, which works even on dumb terminals. But
940 Jamie Zawinski reports that ^M and ^H tricks don't work in
941 Emacs shell buffers, and only make a mess. */
942 || (term && 0 == strcmp (term, "emacs"))
944 && !current_impl_locked)
946 /* We're not printing to a TTY, so revert to the fallback
947 display. #### We're recursively calling
948 set_progress_implementation here, which is slightly kludgy.
949 It would be nicer if we provided that function a return value
950 indicating a failure of some sort. */
951 set_progress_implementation (FALLBACK_PROGRESS_IMPLEMENTATION);
958 progress_handle_sigwinch (int sig)
960 received_sigwinch = 1;
961 signal (SIGWINCH, progress_handle_sigwinch);