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         struct throughput *throughput;
  38         uint64_t start_ns;
  39         struct strbuf counters_sb;
  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 void display(struct progress *progress, uint64_t n, const char *done)
  83 {
  84         const char *tp;
  85         struct strbuf *counters_sb = &progress->counters_sb;
  86         int show_update = 0;
  87         int last_count_len = counters_sb->len;
  88
  89         if (progress->delay && (!progress_update || --progress->delay))
  90                 return;
  91
  92         progress->last_value = n;
  93         tp = (progress->throughput) ? progress->throughput->display.buf : "";
  94         if (progress->total) {
  95                 unsigned percent = n * 100 / progress->total;
  96                 if (percent != progress->last_percent || progress_update) {
  97                         progress->last_percent = percent;
  98
  99                         strbuf_reset(counters_sb);
 100                         strbuf_addf(counters_sb,
 101                                     "%3u%% (%"PRIuMAX"/%"PRIuMAX")%s", percent,
 102                                     (uintmax_t)n, (uintmax_t)progress->total,
 103                                     tp);
 104                         show_update = 1;
 105                 }
 106         } else if (progress_update) {
 107                 strbuf_reset(counters_sb);
 108                 strbuf_addf(counters_sb, "%"PRIuMAX"%s", (uintmax_t)n, tp);
 109                 show_update = 1;
 110         }
 111
 112         if (show_update) {
 113                 if (is_foreground_fd(fileno(stderr)) || done) {
 114                         const char *eol = done ? done : "\r";
 115                         size_t clear_len = counters_sb->len < last_count_len ?
 116                                         last_count_len - counters_sb->len + 1 :
 117                                         0;
 118                         fprintf(stderr, "%s: %s%*s", progress->title,
 119                                 counters_sb->buf, (int) clear_len, eol);
 120                         fflush(stderr);
 121                 }
 122                 progress_update = 0;
 123         }
 124 }
 125
 126 static void throughput_string(struct strbuf *buf, uint64_t total,
 127                               unsigned int rate)
 128 {
 129         strbuf_reset(buf);
 130         strbuf_addstr(buf, ", ");
 131         strbuf_humanise_bytes(buf, total);
 132         strbuf_addstr(buf, " | ");
 133         strbuf_humanise_bytes(buf, rate * 1024);
 134         strbuf_addstr(buf, "/s");
 135 }
 136
 137 void display_throughput(struct progress *progress, uint64_t total)
 138 {
 139         struct throughput *tp;
 140         uint64_t now_ns;
 141         unsigned int misecs, count, rate;
 142
 143         if (!progress)
 144                 return;
 145         tp = progress->throughput;
 146
 147         now_ns = getnanotime();
 148
 149         if (!tp) {
 150                 progress->throughput = tp = calloc(1, sizeof(*tp));
 151                 if (tp) {
 152                         tp->prev_total = tp->curr_total = total;
 153                         tp->prev_ns = now_ns;
 154                         strbuf_init(&tp->display, 0);
 155                 }
 156                 return;
 157         }
 158         tp->curr_total = total;
 159
 160         /* only update throughput every 0.5 s */
 161         if (now_ns - tp->prev_ns <= 500000000)
 162                 return;
 163
 164         /*
 165          * We have x = bytes and y = nanosecs.  We want z = KiB/s:
 166          *
 167          *      z = (x / 1024) / (y / 1000000000)
 168          *      z = x / y * 1000000000 / 1024
 169          *      z = x / (y * 1024 / 1000000000)
 170          *      z = x / y'
 171          *
 172          * To simplify things we'll keep track of misecs, or 1024th of a sec
 173          * obtained with:
 174          *
 175          *      y' = y * 1024 / 1000000000
 176          *      y' = y * (2^10 / 2^42) * (2^42 / 1000000000)
 177          *      y' = y / 2^32 * 4398
 178          *      y' = (y * 4398) >> 32
 179          */
 180         misecs = ((now_ns - tp->prev_ns) * 4398) >> 32;
 181
 182         count = total - tp->prev_total;
 183         tp->prev_total = total;
 184         tp->prev_ns = now_ns;
 185         tp->avg_bytes += count;
 186         tp->avg_misecs += misecs;
 187         rate = tp->avg_bytes / tp->avg_misecs;
 188         tp->avg_bytes -= tp->last_bytes[tp->idx];
 189         tp->avg_misecs -= tp->last_misecs[tp->idx];
 190         tp->last_bytes[tp->idx] = count;
 191         tp->last_misecs[tp->idx] = misecs;
 192         tp->idx = (tp->idx + 1) % TP_IDX_MAX;
 193
 194         throughput_string(&tp->display, total, rate);
 195         if (progress->last_value != -1 && progress_update)
 196                 display(progress, progress->last_value, NULL);
 197 }
 198
 199 void display_progress(struct progress *progress, uint64_t n)
 200 {
 201         if (progress)
 202                 display(progress, n, NULL);
 203 }
 204
 205 static struct progress *start_progress_delay(const char *title, uint64_t total,
 206                                              unsigned delay)
 207 {
 208         struct progress *progress = malloc(sizeof(*progress));
 209         if (!progress) {
 210                 /* unlikely, but here's a good fallback */
 211                 fprintf(stderr, "%s...\n", title);
 212                 fflush(stderr);
 213                 return NULL;
 214         }
 215         progress->title = title;
 216         progress->total = total;
 217         progress->last_value = -1;
 218         progress->last_percent = -1;
 219         progress->delay = delay;
 220         progress->throughput = NULL;
 221         progress->start_ns = getnanotime();
 222         strbuf_init(&progress->counters_sb, 0);
 223         set_progress_signal();
 224         return progress;
 225 }
 226
 227 struct progress *start_delayed_progress(const char *title, uint64_t total)
 228 {
 229         return start_progress_delay(title, total, 2);
 230 }
 231
 232 struct progress *start_progress(const char *title, uint64_t total)
 233 {
 234         return start_progress_delay(title, total, 0);
 235 }
 236
 237 void stop_progress(struct progress **p_progress)
 238 {
 239         stop_progress_msg(p_progress, _("done"));
 240 }
 241
 242 void stop_progress_msg(struct progress **p_progress, const char *msg)
 243 {
 244         struct progress *progress = *p_progress;
 245         if (!progress)
 246                 return;
 247         *p_progress = NULL;
 248         if (progress->last_value != -1) {
 249                 /* Force the last update */
 250                 char *buf;
 251                 struct throughput *tp = progress->throughput;
 252
 253                 if (tp) {
 254                         uint64_t now_ns = getnanotime();
 255                         unsigned int misecs, rate;
 256                         misecs = ((now_ns - progress->start_ns) * 4398) >> 32;
 257                         rate = tp->curr_total / (misecs ? misecs : 1);
 258                         throughput_string(&tp->display, tp->curr_total, rate);
 259                 }
 260                 progress_update = 1;
 261                 buf = xstrfmt(", %s.\n", msg);
 262                 display(progress, progress->last_value, buf);
 263                 free(buf);
 264         }
 265         clear_progress_signal();
 266         strbuf_release(&progress->counters_sb);
 267         if (progress->throughput)
 268                 strbuf_release(&progress->throughput->display);
 269         free(progress->throughput);
 270         free(progress);
 271 }