progress.c

   1 /*
   2  * Simple text-based progress display module for GIT
   3  *
   4  * Copyright (c) 2007 by Nicolas Pitre <nico@fluxnic.net>
   5  *
   6  * This code is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 as
   8  * published by the Free Software Foundation.
   9  */
  10
  11 #include "git-compat-util.h"
  12 #include "gettext.h"
  13 #include "progress.h"
  14 #include "strbuf.h"
  15 #include "trace.h"
  16
  17 #define TP_IDX_MAX      8
  18
  19 struct throughput {
  20         off_t curr_total;
  21         off_t prev_total;
  22         uint64_t prev_ns;
  23         unsigned int avg_bytes;
  24         unsigned int avg_misecs;
  25         unsigned int last_bytes[TP_IDX_MAX];
  26         unsigned int last_misecs[TP_IDX_MAX];
  27         unsigned int idx;
  28         struct strbuf display;
  29 };
  30
  31 struct progress {
  32         const char *title;
  33         uint64_t last_value;
  34         uint64_t total;
  35         unsigned last_percent;
  36         unsigned delay;
  37         unsigned sparse;
  38         struct throughput *throughput;
  39         uint64_t start_ns;
  40 };
  41
  42 static volatile sig_atomic_t progress_update;
  43
  44 static void progress_interval(int signum)
  45 {
  46         progress_update = 1;
  47 }
  48
  49 static void set_progress_signal(void)
  50 {
  51         struct sigaction sa;
  52         struct itimerval v;
  53
  54         progress_update = 0;
  55
  56         memset(&sa, 0, sizeof(sa));
  57         sa.sa_handler = progress_interval;
  58         sigemptyset(&sa.sa_mask);
  59         sa.sa_flags = SA_RESTART;
  60         sigaction(SIGALRM, &sa, NULL);
  61
  62         v.it_interval.tv_sec = 1;
  63         v.it_interval.tv_usec = 0;
  64         v.it_value = v.it_interval;
  65         setitimer(ITIMER_REAL, &v, NULL);
  66 }
  67
  68 static void clear_progress_signal(void)
  69 {
  70         struct itimerval v = {{0,},};
  71         setitimer(ITIMER_REAL, &v, NULL);
  72         signal(SIGALRM, SIG_IGN);
  73         progress_update = 0;
  74 }
  75
  76 static int is_foreground_fd(int fd)
  77 {
  78         int tpgrp = tcgetpgrp(fd);
  79         return tpgrp < 0 || tpgrp == getpgid(0);
  80 }
  81
  82 static int display(struct progress *progress, uint64_t n, const char *done)
  83 {
  84         const char *eol, *tp;
  85
  86         if (progress->delay && (!progress_update || --progress->delay))
  87                 return 0;
  88
  89         progress->last_value = n;
  90         tp = (progress->throughput) ? progress->throughput->display.buf : "";
  91         eol = done ? done : "   \r";
  92         if (progress->total) {
  93                 unsigned percent = n * 100 / progress->total;
  94                 if (percent != progress->last_percent || progress_update) {
  95                         progress->last_percent = percent;
  96                         if (is_foreground_fd(fileno(stderr)) || done) {
  97                                 fprintf(stderr, "%s: %3u%% (%"PRIuMAX"/%"PRIuMAX")%s%s",
  98                                         progress->title, percent,
  99                                         (uintmax_t)n, (uintmax_t)progress->total,
 100                                         tp, eol);
 101                                 fflush(stderr);
 102                         }
 103                         progress_update = 0;
 104                         return 1;
 105                 }
 106         } else if (progress_update) {
 107                 if (is_foreground_fd(fileno(stderr)) || done) {
 108                         fprintf(stderr, "%s: %"PRIuMAX"%s%s",
 109                                 progress->title, (uintmax_t)n, tp, eol);
 110                         fflush(stderr);
 111                 }
 112                 progress_update = 0;
 113                 return 1;
 114         }
 115
 116         return 0;
 117 }
 118
 119 static void throughput_string(struct strbuf *buf, uint64_t total,
 120                               unsigned int rate)
 121 {
 122         strbuf_reset(buf);
 123         strbuf_addstr(buf, ", ");
 124         strbuf_humanise_bytes(buf, total);
 125         strbuf_addstr(buf, " | ");
 126         strbuf_humanise_bytes(buf, rate * 1024);
 127         strbuf_addstr(buf, "/s");
 128 }
 129
 130 void display_throughput(struct progress *progress, uint64_t total)
 131 {
 132         struct throughput *tp;
 133         uint64_t now_ns;
 134         unsigned int misecs, count, rate;
 135
 136         if (!progress)
 137                 return;
 138         tp = progress->throughput;
 139
 140         now_ns = getnanotime();
 141
 142         if (!tp) {
 143                 progress->throughput = tp = calloc(1, sizeof(*tp));
 144                 if (tp) {
 145                         tp->prev_total = tp->curr_total = total;
 146                         tp->prev_ns = now_ns;
 147                         strbuf_init(&tp->display, 0);
 148                 }
 149                 return;
 150         }
 151         tp->curr_total = total;
 152
 153         /* only update throughput every 0.5 s */
 154         if (now_ns - tp->prev_ns <= 500000000)
 155                 return;
 156
 157         /*
 158          * We have x = bytes and y = nanosecs.  We want z = KiB/s:
 159          *
 160          *      z = (x / 1024) / (y / 1000000000)
 161          *      z = x / y * 1000000000 / 1024
 162          *      z = x / (y * 1024 / 1000000000)
 163          *      z = x / y'
 164          *
 165          * To simplify things we'll keep track of misecs, or 1024th of a sec
 166          * obtained with:
 167          *
 168          *      y' = y * 1024 / 1000000000
 169          *      y' = y * (2^10 / 2^42) * (2^42 / 1000000000)
 170          *      y' = y / 2^32 * 4398
 171          *      y' = (y * 4398) >> 32
 172          */
 173         misecs = ((now_ns - tp->prev_ns) * 4398) >> 32;
 174
 175         count = total - tp->prev_total;
 176         tp->prev_total = total;
 177         tp->prev_ns = now_ns;
 178         tp->avg_bytes += count;
 179         tp->avg_misecs += misecs;
 180         rate = tp->avg_bytes / tp->avg_misecs;
 181         tp->avg_bytes -= tp->last_bytes[tp->idx];
 182         tp->avg_misecs -= tp->last_misecs[tp->idx];
 183         tp->last_bytes[tp->idx] = count;
 184         tp->last_misecs[tp->idx] = misecs;
 185         tp->idx = (tp->idx + 1) % TP_IDX_MAX;
 186
 187         throughput_string(&tp->display, total, rate);
 188         if (progress->last_value != -1 && progress_update)
 189                 display(progress, progress->last_value, NULL);
 190 }
 191
 192 int display_progress(struct progress *progress, uint64_t n)
 193 {
 194         return progress ? display(progress, n, NULL) : 0;
 195 }
 196
 197 static struct progress *start_progress_delay(const char *title, uint64_t total,
 198                                              unsigned delay, unsigned sparse)
 199 {
 200         struct progress *progress = malloc(sizeof(*progress));
 201         if (!progress) {
 202                 /* unlikely, but here's a good fallback */
 203                 fprintf(stderr, "%s...\n", title);
 204                 fflush(stderr);
 205                 return NULL;
 206         }
 207         progress->title = title;
 208         progress->total = total;
 209         progress->last_value = -1;
 210         progress->last_percent = -1;
 211         progress->delay = delay;
 212         progress->sparse = sparse;
 213         progress->throughput = NULL;
 214         progress->start_ns = getnanotime();
 215         set_progress_signal();
 216         return progress;
 217 }
 218
 219 struct progress *start_delayed_progress(const char *title, uint64_t total)
 220 {
 221         return start_progress_delay(title, total, 2, 0);
 222 }
 223
 224 struct progress *start_progress(const char *title, uint64_t total)
 225 {
 226         return start_progress_delay(title, total, 0, 0);
 227 }
 228
 229 /*
 230  * Here "sparse" means that the caller might use some sampling criteria to
 231  * decide when to call display_progress() rather than calling it for every
 232  * integer value in[0 .. total).  In particular, the caller might not call
 233  * display_progress() for the last value in the range.
 234  *
 235  * When "sparse" is set, stop_progress() will automatically force the done
 236  * message to show 100%.
 237  */
 238 struct progress *start_sparse_progress(const char *title, uint64_t total)
 239 {
 240         return start_progress_delay(title, total, 0, 1);
 241 }
 242
 243 struct progress *start_delayed_sparse_progress(const char *title,
 244                                                uint64_t total)
 245 {
 246         return start_progress_delay(title, total, 2, 1);
 247 }
 248
 249 static void finish_if_sparse(struct progress *progress)
 250 {
 251         if (progress &&
 252             progress->sparse &&
 253             progress->last_value != progress->total)
 254                 display_progress(progress, progress->total);
 255 }
 256
 257 void stop_progress(struct progress **p_progress)
 258 {
 259         finish_if_sparse(*p_progress);
 260
 261         stop_progress_msg(p_progress, _("done"));
 262 }
 263
 264 void stop_progress_msg(struct progress **p_progress, const char *msg)
 265 {
 266         struct progress *progress = *p_progress;
 267         if (!progress)
 268                 return;
 269         *p_progress = NULL;
 270         if (progress->last_value != -1) {
 271                 /* Force the last update */
 272                 char *buf;
 273                 struct throughput *tp = progress->throughput;
 274
 275                 if (tp) {
 276                         uint64_t now_ns = getnanotime();
 277                         unsigned int misecs, rate;
 278                         misecs = ((now_ns - progress->start_ns) * 4398) >> 32;
 279                         rate = tp->curr_total / (misecs ? misecs : 1);
 280                         throughput_string(&tp->display, tp->curr_total, rate);
 281                 }
 282                 progress_update = 1;
 283                 buf = xstrfmt(", %s.\n", msg);
 284                 display(progress, progress->last_value, buf);
 285                 free(buf);
 286         }
 287         clear_progress_signal();
 288         if (progress->throughput)
 289                 strbuf_release(&progress->throughput->display);
 290         free(progress->throughput);
 291         free(progress);
 292 }