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
  16 #define TP_IDX_MAX      8
  17
  18 struct throughput {
  19         off_t curr_total;
  20         off_t prev_total;
  21         struct timeval prev_tv;
  22         unsigned int avg_bytes;
  23         unsigned int avg_misecs;
  24         unsigned int last_bytes[TP_IDX_MAX];
  25         unsigned int last_misecs[TP_IDX_MAX];
  26         unsigned int idx;
  27         char display[32];
  28 };
  29
  30 struct progress {
  31         const char *title;
  32         int last_value;
  33         unsigned total;
  34         unsigned last_percent;
  35         unsigned delay;
  36         unsigned delayed_percent_treshold;
  37         struct throughput *throughput;
  38 };
  39
  40 static volatile sig_atomic_t progress_update;
  41
  42 static void progress_interval(int signum)
  43 {
  44         progress_update = 1;
  45 }
  46
  47 static void set_progress_signal(void)
  48 {
  49         struct sigaction sa;
  50         struct itimerval v;
  51
  52         progress_update = 0;
  53
  54         memset(&sa, 0, sizeof(sa));
  55         sa.sa_handler = progress_interval;
  56         sigemptyset(&sa.sa_mask);
  57         sa.sa_flags = SA_RESTART;
  58         sigaction(SIGALRM, &sa, NULL);
  59
  60         v.it_interval.tv_sec = 1;
  61         v.it_interval.tv_usec = 0;
  62         v.it_value = v.it_interval;
  63         setitimer(ITIMER_REAL, &v, NULL);
  64 }
  65
  66 static void clear_progress_signal(void)
  67 {
  68         struct itimerval v = {{0,},};
  69         setitimer(ITIMER_REAL, &v, NULL);
  70         signal(SIGALRM, SIG_IGN);
  71         progress_update = 0;
  72 }
  73
  74 static int display(struct progress *progress, unsigned n, const char *done)
  75 {
  76         const char *eol, *tp;
  77
  78         if (progress->delay) {
  79                 if (!progress_update || --progress->delay)
  80                         return 0;
  81                 if (progress->total) {
  82                         unsigned percent = n * 100 / progress->total;
  83                         if (percent > progress->delayed_percent_treshold) {
  84                                 /* inhibit this progress report entirely */
  85                                 clear_progress_signal();
  86                                 progress->delay = -1;
  87                                 progress->total = 0;
  88                                 return 0;
  89                         }
  90                 }
  91         }
  92
  93         progress->last_value = n;
  94         tp = (progress->throughput) ? progress->throughput->display : "";
  95         eol = done ? done : "   \r";
  96         if (progress->total) {
  97                 unsigned percent = n * 100 / progress->total;
  98                 if (percent != progress->last_percent || progress_update) {
  99                         progress->last_percent = percent;
 100                         fprintf(stderr, "%s: %3u%% (%u/%u)%s%s",
 101                                 progress->title, percent, n,
 102                                 progress->total, tp, eol);
 103                         fflush(stderr);
 104                         progress_update = 0;
 105                         return 1;
 106                 }
 107         } else if (progress_update) {
 108                 fprintf(stderr, "%s: %u%s%s", progress->title, n, tp, eol);
 109                 fflush(stderr);
 110                 progress_update = 0;
 111                 return 1;
 112         }
 113
 114         return 0;
 115 }
 116
 117 static void throughput_string(struct strbuf *buf, off_t total,
 118                               unsigned int rate)
 119 {
 120         strbuf_addstr(buf, ", ");
 121         strbuf_humanise_bytes(buf, total);
 122         strbuf_addstr(buf, " | ");
 123         strbuf_humanise_bytes(buf, rate * 1024);
 124         strbuf_addstr(buf, "/s");
 125 }
 126
 127 void display_throughput(struct progress *progress, off_t total)
 128 {
 129         struct throughput *tp;
 130         struct timeval tv;
 131         unsigned int misecs;
 132
 133         if (!progress)
 134                 return;
 135         tp = progress->throughput;
 136
 137         gettimeofday(&tv, NULL);
 138
 139         if (!tp) {
 140                 progress->throughput = tp = calloc(1, sizeof(*tp));
 141                 if (tp) {
 142                         tp->prev_total = tp->curr_total = total;
 143                         tp->prev_tv = tv;
 144                 }
 145                 return;
 146         }
 147         tp->curr_total = total;
 148
 149         /*
 150          * We have x = bytes and y = microsecs.  We want z = KiB/s:
 151          *
 152          *      z = (x / 1024) / (y / 1000000)
 153          *      z = x / y * 1000000 / 1024
 154          *      z = x / (y * 1024 / 1000000)
 155          *      z = x / y'
 156          *
 157          * To simplify things we'll keep track of misecs, or 1024th of a sec
 158          * obtained with:
 159          *
 160          *      y' = y * 1024 / 1000000
 161          *      y' = y / (1000000 / 1024)
 162          *      y' = y / 977
 163          */
 164         misecs = (tv.tv_sec - tp->prev_tv.tv_sec) * 1024;
 165         misecs += (int)(tv.tv_usec - tp->prev_tv.tv_usec) / 977;
 166
 167         if (misecs > 512) {
 168                 struct strbuf buf = STRBUF_INIT;
 169                 unsigned int count, rate;
 170
 171                 count = total - tp->prev_total;
 172                 tp->prev_total = total;
 173                 tp->prev_tv = tv;
 174                 tp->avg_bytes += count;
 175                 tp->avg_misecs += misecs;
 176                 rate = tp->avg_bytes / tp->avg_misecs;
 177                 tp->avg_bytes -= tp->last_bytes[tp->idx];
 178                 tp->avg_misecs -= tp->last_misecs[tp->idx];
 179                 tp->last_bytes[tp->idx] = count;
 180                 tp->last_misecs[tp->idx] = misecs;
 181                 tp->idx = (tp->idx + 1) % TP_IDX_MAX;
 182
 183                 throughput_string(&buf, total, rate);
 184                 strncpy(tp->display, buf.buf, sizeof(tp->display));
 185                 strbuf_release(&buf);
 186                 if (progress->last_value != -1 && progress_update)
 187                         display(progress, progress->last_value, NULL);
 188         }
 189 }
 190
 191 int display_progress(struct progress *progress, unsigned n)
 192 {
 193         return progress ? display(progress, n, NULL) : 0;
 194 }
 195
 196 struct progress *start_progress_delay(const char *title, unsigned total,
 197                                        unsigned percent_treshold, unsigned delay)
 198 {
 199         struct progress *progress = malloc(sizeof(*progress));
 200         if (!progress) {
 201                 /* unlikely, but here's a good fallback */
 202                 fprintf(stderr, "%s...\n", title);
 203                 fflush(stderr);
 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         stop_progress_msg(p_progress, _("done"));
 225 }
 226
 227 void stop_progress_msg(struct progress **p_progress, const char *msg)
 228 {
 229         struct progress *progress = *p_progress;
 230         if (!progress)
 231                 return;
 232         *p_progress = NULL;
 233         if (progress->last_value != -1) {
 234                 /* Force the last update */
 235                 char buf[128], *bufp;
 236                 size_t len = strlen(msg) + 5;
 237                 struct throughput *tp = progress->throughput;
 238
 239                 bufp = (len < sizeof(buf)) ? buf : xmalloc(len + 1);
 240                 if (tp) {
 241                         struct strbuf strbuf = STRBUF_INIT;
 242                         unsigned int rate = !tp->avg_misecs ? 0 :
 243                                         tp->avg_bytes / tp->avg_misecs;
 244                         throughput_string(&strbuf, tp->curr_total, rate);
 245                         strncpy(tp->display, strbuf.buf, sizeof(tp->display));
 246                         strbuf_release(&strbuf);
 247                 }
 248                 progress_update = 1;
 249                 sprintf(bufp, ", %s.\n", msg);
 250                 display(progress, progress->last_value, bufp);
 251                 if (buf != bufp)
 252                         free(bufp);
 253         }
 254         clear_progress_signal();
 255         free(progress->throughput);
 256         free(progress);
 257 }