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         off_t curr_total;
  18         off_t prev_total;
  19         struct timeval prev_tv;
  20         unsigned int avg_bytes;
  21         unsigned int avg_misecs;
  22         unsigned int last_bytes[TP_IDX_MAX];
  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, const char *done)
  73 {
  74         const 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 : "   \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                         fflush(stderr);
 102                         progress_update = 0;
 103                         return 1;
 104                 }
 105         } else if (progress_update) {
 106                 fprintf(stderr, "%s: %u%s%s", progress->title, n, tp, eol);
 107                 fflush(stderr);
 108                 progress_update = 0;
 109                 return 1;
 110         }
 111
 112         return 0;
 113 }
 114
 115 static void throughput_string(struct throughput *tp, off_t total,
 116                               unsigned int rate)
 117 {
 118         int l = sizeof(tp->display);
 119         if (total > 1 << 30) {
 120                 l -= snprintf(tp->display, l, ", %u.%2.2u GiB",
 121                               (int)(total >> 30),
 122                               (int)(total & ((1 << 30) - 1)) / 10737419);
 123         } else if (total > 1 << 20) {
 124                 l -= snprintf(tp->display, l, ", %u.%2.2u MiB",
 125                               (int)(total >> 20),
 126                               ((int)(total & ((1 << 20) - 1)) * 100) >> 20);
 127         } else if (total > 1 << 10) {
 128                 l -= snprintf(tp->display, l, ", %u.%2.2u KiB",
 129                               (int)(total >> 10),
 130                               ((int)(total & ((1 << 10) - 1)) * 100) >> 10);
 131         } else {
 132                 l -= snprintf(tp->display, l, ", %u bytes", (int)total);
 133         }
 134         if (rate)
 135                 snprintf(tp->display + sizeof(tp->display) - l, l,
 136                          " | %u KiB/s", rate);
 137 }
 138
 139 void display_throughput(struct progress *progress, off_t total)
 140 {
 141         struct throughput *tp;
 142         struct timeval tv;
 143         unsigned int misecs;
 144
 145         if (!progress)
 146                 return;
 147         tp = progress->throughput;
 148
 149         gettimeofday(&tv, NULL);
 150
 151         if (!tp) {
 152                 progress->throughput = tp = calloc(1, sizeof(*tp));
 153                 if (tp) {
 154                         tp->prev_total = tp->curr_total = total;
 155                         tp->prev_tv = tv;
 156                 }
 157                 return;
 158         }
 159         tp->curr_total = total;
 160
 161         /*
 162          * We have x = bytes and y = microsecs.  We want z = KiB/s:
 163          *
 164          *      z = (x / 1024) / (y / 1000000)
 165          *      z = x / y * 1000000 / 1024
 166          *      z = x / (y * 1024 / 1000000)
 167          *      z = x / y'
 168          *
 169          * To simplify things we'll keep track of misecs, or 1024th of a sec
 170          * obtained with:
 171          *
 172          *      y' = y * 1024 / 1000000
 173          *      y' = y / (1000000 / 1024)
 174          *      y' = y / 977
 175          */
 176         misecs = (tv.tv_sec - tp->prev_tv.tv_sec) * 1024;
 177         misecs += (int)(tv.tv_usec - tp->prev_tv.tv_usec) / 977;
 178
 179         if (misecs > 512) {
 180                 unsigned int count, rate;
 181
 182                 count = total - tp->prev_total;
 183                 tp->prev_total = total;
 184                 tp->prev_tv = tv;
 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, total, rate);
 195                 if (progress->last_value != -1 && progress_update)
 196                         display(progress, progress->last_value, NULL);
 197         }
 198 }
 199
 200 int display_progress(struct progress *progress, unsigned n)
 201 {
 202         return progress ? display(progress, n, NULL) : 0;
 203 }
 204
 205 struct progress *start_progress_delay(const char *title, unsigned total,
 206                                        unsigned percent_treshold, 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->delayed_percent_treshold = percent_treshold;
 220         progress->delay = delay;
 221         progress->throughput = NULL;
 222         set_progress_signal();
 223         return progress;
 224 }
 225
 226 struct progress *start_progress(const char *title, unsigned total)
 227 {
 228         return start_progress_delay(title, total, 0, 0);
 229 }
 230
 231 void stop_progress(struct progress **p_progress)
 232 {
 233         stop_progress_msg(p_progress, "done");
 234 }
 235
 236 void stop_progress_msg(struct progress **p_progress, const char *msg)
 237 {
 238         struct progress *progress = *p_progress;
 239         if (!progress)
 240                 return;
 241         *p_progress = NULL;
 242         if (progress->last_value != -1) {
 243                 /* Force the last update */
 244                 char buf[strlen(msg) + 5];
 245                 struct throughput *tp = progress->throughput;
 246                 if (tp) {
 247                         unsigned int rate = !tp->avg_misecs ? 0 :
 248                                         tp->avg_bytes / tp->avg_misecs;
 249                         throughput_string(tp, tp->curr_total, rate);
 250                 }
 251                 progress_update = 1;
 252                 sprintf(buf, ", %s.\n", msg);
 253                 display(progress, progress->last_value, buf);
 254         }
 255         clear_progress_signal();
 256         free(progress->throughput);
 257         free(progress);
 258 }