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 "progress.h"
  13 #include "strbuf.h"
  14
  15 #define TP_IDX_MAX      8
  16
  17 struct throughput {
  18         off_t curr_total;
  19         off_t prev_total;
  20         struct timeval prev_tv;
  21         unsigned int avg_bytes;
  22         unsigned int avg_misecs;
  23         unsigned int last_bytes[TP_IDX_MAX];
  24         unsigned int last_misecs[TP_IDX_MAX];
  25         unsigned int idx;
  26         char display[32];
  27 };
  28
  29 struct progress {
  30         const char *title;
  31         int last_value;
  32         unsigned total;
  33         unsigned last_percent;
  34         unsigned delay;
  35         unsigned delayed_percent_treshold;
  36         struct throughput *throughput;
  37 };
  38
  39 static volatile sig_atomic_t progress_update;
  40
  41 static void progress_interval(int signum)
  42 {
  43         progress_update = 1;
  44 }
  45
  46 static void set_progress_signal(void)
  47 {
  48         struct sigaction sa;
  49         struct itimerval v;
  50
  51         progress_update = 0;
  52
  53         memset(&sa, 0, sizeof(sa));
  54         sa.sa_handler = progress_interval;
  55         sigemptyset(&sa.sa_mask);
  56         sa.sa_flags = SA_RESTART;
  57         sigaction(SIGALRM, &sa, NULL);
  58
  59         v.it_interval.tv_sec = 1;
  60         v.it_interval.tv_usec = 0;
  61         v.it_value = v.it_interval;
  62         setitimer(ITIMER_REAL, &v, NULL);
  63 }
  64
  65 static void clear_progress_signal(void)
  66 {
  67         struct itimerval v = {{0,},};
  68         setitimer(ITIMER_REAL, &v, NULL);
  69         signal(SIGALRM, SIG_IGN);
  70         progress_update = 0;
  71 }
  72
  73 static int display(struct progress *progress, unsigned n, const char *done)
  74 {
  75         const char *eol, *tp;
  76
  77         if (progress->delay) {
  78                 if (!progress_update || --progress->delay)
  79                         return 0;
  80                 if (progress->total) {
  81                         unsigned percent = n * 100 / progress->total;
  82                         if (percent > progress->delayed_percent_treshold) {
  83                                 /* inhibit this progress report entirely */
  84                                 clear_progress_signal();
  85                                 progress->delay = -1;
  86                                 progress->total = 0;
  87                                 return 0;
  88                         }
  89                 }
  90         }
  91
  92         progress->last_value = n;
  93         tp = (progress->throughput) ? progress->throughput->display : "";
  94         eol = done ? done : "   \r";
  95         if (progress->total) {
  96                 unsigned percent = n * 100 / progress->total;
  97                 if (percent != progress->last_percent || progress_update) {
  98                         progress->last_percent = percent;
  99                         fprintf(stderr, "%s: %3u%% (%u/%u)%s%s",
 100                                 progress->title, percent, n,
 101                                 progress->total, tp, eol);
 102                         fflush(stderr);
 103                         progress_update = 0;
 104                         return 1;
 105                 }
 106         } else if (progress_update) {
 107                 fprintf(stderr, "%s: %u%s%s", progress->title, n, tp, eol);
 108                 fflush(stderr);
 109                 progress_update = 0;
 110                 return 1;
 111         }
 112
 113         return 0;
 114 }
 115
 116 static void throughput_string(struct strbuf *buf, off_t total,
 117                               unsigned int rate)
 118 {
 119         strbuf_addstr(buf, ", ");
 120         strbuf_humanise_bytes(buf, total);
 121         strbuf_addstr(buf, " | ");
 122         strbuf_humanise_bytes(buf, rate * 1024);
 123         strbuf_addstr(buf, "/s");
 124 }
 125
 126 void display_throughput(struct progress *progress, off_t total)
 127 {
 128         struct throughput *tp;
 129         struct timeval tv;
 130         unsigned int misecs;
 131
 132         if (!progress)
 133                 return;
 134         tp = progress->throughput;
 135
 136         gettimeofday(&tv, NULL);
 137
 138         if (!tp) {
 139                 progress->throughput = tp = calloc(1, sizeof(*tp));
 140                 if (tp) {
 141                         tp->prev_total = tp->curr_total = total;
 142                         tp->prev_tv = tv;
 143                 }
 144                 return;
 145         }
 146         tp->curr_total = total;
 147
 148         /*
 149          * We have x = bytes and y = microsecs.  We want z = KiB/s:
 150          *
 151          *      z = (x / 1024) / (y / 1000000)
 152          *      z = x / y * 1000000 / 1024
 153          *      z = x / (y * 1024 / 1000000)
 154          *      z = x / y'
 155          *
 156          * To simplify things we'll keep track of misecs, or 1024th of a sec
 157          * obtained with:
 158          *
 159          *      y' = y * 1024 / 1000000
 160          *      y' = y / (1000000 / 1024)
 161          *      y' = y / 977
 162          */
 163         misecs = (tv.tv_sec - tp->prev_tv.tv_sec) * 1024;
 164         misecs += (int)(tv.tv_usec - tp->prev_tv.tv_usec) / 977;
 165
 166         if (misecs > 512) {
 167                 struct strbuf buf = STRBUF_INIT;
 168                 unsigned int count, rate;
 169
 170                 count = total - tp->prev_total;
 171                 tp->prev_total = total;
 172                 tp->prev_tv = tv;
 173                 tp->avg_bytes += count;
 174                 tp->avg_misecs += misecs;
 175                 rate = tp->avg_bytes / tp->avg_misecs;
 176                 tp->avg_bytes -= tp->last_bytes[tp->idx];
 177                 tp->avg_misecs -= tp->last_misecs[tp->idx];
 178                 tp->last_bytes[tp->idx] = count;
 179                 tp->last_misecs[tp->idx] = misecs;
 180                 tp->idx = (tp->idx + 1) % TP_IDX_MAX;
 181
 182                 throughput_string(&buf, total, rate);
 183                 strncpy(tp->display, buf.buf, sizeof(tp->display));
 184                 strbuf_release(&buf);
 185                 if (progress->last_value != -1 && progress_update)
 186                         display(progress, progress->last_value, NULL);
 187         }
 188 }
 189
 190 int display_progress(struct progress *progress, unsigned n)
 191 {
 192         return progress ? display(progress, n, NULL) : 0;
 193 }
 194
 195 struct progress *start_progress_delay(const char *title, unsigned total,
 196                                        unsigned percent_treshold, unsigned delay)
 197 {
 198         struct progress *progress = malloc(sizeof(*progress));
 199         if (!progress) {
 200                 /* unlikely, but here's a good fallback */
 201                 fprintf(stderr, "%s...\n", title);
 202                 fflush(stderr);
 203                 return NULL;
 204         }
 205         progress->title = title;
 206         progress->total = total;
 207         progress->last_value = -1;
 208         progress->last_percent = -1;
 209         progress->delayed_percent_treshold = percent_treshold;
 210         progress->delay = delay;
 211         progress->throughput = NULL;
 212         set_progress_signal();
 213         return progress;
 214 }
 215
 216 struct progress *start_progress(const char *title, unsigned total)
 217 {
 218         return start_progress_delay(title, total, 0, 0);
 219 }
 220
 221 void stop_progress(struct progress **p_progress)
 222 {
 223         stop_progress_msg(p_progress, "done");
 224 }
 225
 226 void stop_progress_msg(struct progress **p_progress, const char *msg)
 227 {
 228         struct progress *progress = *p_progress;
 229         if (!progress)
 230                 return;
 231         *p_progress = NULL;
 232         if (progress->last_value != -1) {
 233                 /* Force the last update */
 234                 char buf[128], *bufp;
 235                 size_t len = strlen(msg) + 5;
 236                 struct throughput *tp = progress->throughput;
 237
 238                 bufp = (len < sizeof(buf)) ? buf : xmalloc(len + 1);
 239                 if (tp) {
 240                         struct strbuf strbuf = STRBUF_INIT;
 241                         unsigned int rate = !tp->avg_misecs ? 0 :
 242                                         tp->avg_bytes / tp->avg_misecs;
 243                         throughput_string(&strbuf, tp->curr_total, rate);
 244                         strncpy(tp->display, strbuf.buf, sizeof(tp->display));
 245                         strbuf_release(&strbuf);
 246                 }
 247                 progress_update = 1;
 248                 sprintf(bufp, ", %s.\n", msg);
 249                 display(progress, progress->last_value, bufp);
 250                 if (buf != bufp)
 251                         free(bufp);
 252         }
 253         clear_progress_signal();
 254         free(progress->throughput);
 255         free(progress);
 256 }