progress.c

   1 /*
   2  * Simple text-based progress display module for GIT
   3  *
   4  * Copyright (c) 2007 by Nicolas Pitre <nico@cam.org>
   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 "progress.h"
  13
  14 #define TP_IDX_MAX      8
  15
  16 struct throughput {
  17         struct timeval prev_tv;
  18         off_t total;
  19         unsigned long count;
  20         unsigned long avg_bytes;
  21         unsigned long last_bytes[TP_IDX_MAX];
  22         unsigned int avg_misecs;
  23         unsigned int last_misecs[TP_IDX_MAX];
  24         unsigned int idx;
  25         char display[32];
  26 };
  27
  28 struct progress {
  29         const char *title;
  30         int last_value;
  31         unsigned total;
  32         unsigned last_percent;
  33         unsigned delay;
  34         unsigned delayed_percent_treshold;
  35         struct throughput *throughput;
  36 };
  37
  38 static volatile sig_atomic_t progress_update;
  39
  40 static void progress_interval(int signum)
  41 {
  42         progress_update = 1;
  43 }
  44
  45 static void set_progress_signal(void)
  46 {
  47         struct sigaction sa;
  48         struct itimerval v;
  49
  50         progress_update = 0;
  51
  52         memset(&sa, 0, sizeof(sa));
  53         sa.sa_handler = progress_interval;
  54         sigemptyset(&sa.sa_mask);
  55         sa.sa_flags = SA_RESTART;
  56         sigaction(SIGALRM, &sa, NULL);
  57
  58         v.it_interval.tv_sec = 1;
  59         v.it_interval.tv_usec = 0;
  60         v.it_value = v.it_interval;
  61         setitimer(ITIMER_REAL, &v, NULL);
  62 }
  63
  64 static void clear_progress_signal(void)
  65 {
  66         struct itimerval v = {{0,},};
  67         setitimer(ITIMER_REAL, &v, NULL);
  68         signal(SIGALRM, SIG_IGN);
  69         progress_update = 0;
  70 }
  71
  72 static int display(struct progress *progress, unsigned n, int done)
  73 {
  74         char *eol, *tp;
  75
  76         if (progress->delay) {
  77                 if (!progress_update || --progress->delay)
  78                         return 0;
  79                 if (progress->total) {
  80                         unsigned percent = n * 100 / progress->total;
  81                         if (percent > progress->delayed_percent_treshold) {
  82                                 /* inhibit this progress report entirely */
  83                                 clear_progress_signal();
  84                                 progress->delay = -1;
  85                                 progress->total = 0;
  86                                 return 0;
  87                         }
  88                 }
  89         }
  90
  91         progress->last_value = n;
  92         tp = (progress->throughput) ? progress->throughput->display : "";
  93         eol = done ? ", done.   \n" : "   \r";
  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                         fprintf(stderr, "%s: %3u%% (%u/%u)%s%s",
  99                                 progress->title, percent, n,
 100                                 progress->total, tp, eol);
 101                         progress_update = 0;
 102                         return 1;
 103                 }
 104         } else if (progress_update) {
 105                 fprintf(stderr, "%s: %u%s%s", progress->title, n, tp, eol);
 106                 progress_update = 0;
 107                 return 1;
 108         }
 109
 110         return 0;
 111 }
 112
 113 void display_throughput(struct progress *progress, unsigned long n)
 114 {
 115         struct throughput *tp;
 116         struct timeval tv;
 117         unsigned int misecs;
 118
 119         if (!progress)
 120                 return;
 121         tp = progress->throughput;
 122
 123         gettimeofday(&tv, NULL);
 124
 125         if (!tp) {
 126                 progress->throughput = tp = calloc(1, sizeof(*tp));
 127                 if (tp)
 128                         tp->prev_tv = tv;
 129                 return;
 130         }
 131
 132         tp->total += n;
 133         tp->count += n;
 134
 135         /*
 136          * We have x = bytes and y = microsecs.  We want z = KiB/s:
 137          *
 138          *      z = (x / 1024) / (y / 1000000)
 139          *      z = x / y * 1000000 / 1024
 140          *      z = x / (y * 1024 / 1000000)
 141          *      z = x / y'
 142          *
 143          * To simplify things we'll keep track of misecs, or 1024th of a sec
 144          * obtained with:
 145          *
 146          *      y' = y * 1024 / 1000000
 147          *      y' = y / (1000000 / 1024)
 148          *      y' = y / 977
 149          */
 150         misecs = (tv.tv_sec - tp->prev_tv.tv_sec) * 1024;
 151         misecs += (int)(tv.tv_usec - tp->prev_tv.tv_usec) / 977;
 152
 153         if (misecs > 512) {
 154                 int l = sizeof(tp->display);
 155                 tp->prev_tv = tv;
 156                 tp->avg_bytes += tp->count;
 157                 tp->avg_misecs += misecs;
 158
 159                 if (tp->total > 1 << 30) {
 160                         l -= snprintf(tp->display, l, ", %u.%2.2u GiB",
 161                                       (int)(tp->total >> 30),
 162                                       (int)(tp->total & ((1 << 30) - 1)) / 10737419);
 163                 } else if (tp->total > 1 << 20) {
 164                         l -= snprintf(tp->display, l, ", %u.%2.2u MiB",
 165                                       (int)(tp->total >> 20),
 166                                       ((int)(tp->total & ((1 << 20) - 1))
 167                                        * 100) >> 20);
 168                 } else if (tp->total > 1 << 10) {
 169                         l -= snprintf(tp->display, l, ", %u.%2.2u KiB",
 170                                       (int)(tp->total >> 10),
 171                                       ((int)(tp->total & ((1 << 10) - 1))
 172                                        * 100) >> 10);
 173                 } else {
 174                         l -= snprintf(tp->display, l, ", %u bytes",
 175                                       (int)tp->total);
 176                 }
 177                 snprintf(tp->display + sizeof(tp->display) - l, l,
 178                          " | %lu KiB/s", tp->avg_bytes / tp->avg_misecs);
 179
 180                 tp->avg_bytes -= tp->last_bytes[tp->idx];
 181                 tp->avg_misecs -= tp->last_misecs[tp->idx];
 182                 tp->last_bytes[tp->idx] = tp->count;
 183                 tp->last_misecs[tp->idx] = misecs;
 184                 tp->idx = (tp->idx + 1) % TP_IDX_MAX;
 185                 tp->count = 0;
 186
 187                 if (progress->last_value != -1 && progress_update)
 188                         display(progress, progress->last_value, 0);
 189         }
 190 }
 191
 192 int display_progress(struct progress *progress, unsigned n)
 193 {
 194         return progress ? display(progress, n, 0) : 0;
 195 }
 196
 197 struct progress *start_progress_delay(const char *title, unsigned total,
 198                                        unsigned percent_treshold, unsigned delay)
 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                 return NULL;
 205         }
 206         progress->title = title;
 207         progress->total = total;
 208         progress->last_value = -1;
 209         progress->last_percent = -1;
 210         progress->delayed_percent_treshold = percent_treshold;
 211         progress->delay = delay;
 212         progress->throughput = NULL;
 213         set_progress_signal();
 214         return progress;
 215 }
 216
 217 struct progress *start_progress(const char *title, unsigned total)
 218 {
 219         return start_progress_delay(title, total, 0, 0);
 220 }
 221
 222 void stop_progress(struct progress **p_progress)
 223 {
 224         struct progress *progress = *p_progress;
 225         if (!progress)
 226                 return;
 227         *p_progress = NULL;
 228         if (progress->last_value != -1) {
 229                 /* Force the last update */
 230                 progress_update = 1;
 231                 display(progress, progress->last_value, 1);
 232         }
 233         clear_progress_signal();
 234         free(progress->throughput);
 235         free(progress);
 236 }