progress.c

   1 #include "git-compat-util.h"
   2 #include "progress.h"
   3
   4 #define TP_IDX_MAX      8
   5
   6 struct throughput {
   7         struct timeval prev_tv;
   8         unsigned long count;
   9         unsigned long avg_bytes;
  10         unsigned long last_bytes[TP_IDX_MAX];
  11         unsigned int avg_misecs;
  12         unsigned int last_misecs[TP_IDX_MAX];
  13         unsigned int idx;
  14         char display[20];
  15 };
  16
  17 struct progress {
  18         const char *title;
  19         int last_value;
  20         unsigned total;
  21         unsigned last_percent;
  22         unsigned delay;
  23         unsigned delayed_percent_treshold;
  24         struct throughput *throughput;
  25 };
  26
  27 static volatile sig_atomic_t progress_update;
  28
  29 static void progress_interval(int signum)
  30 {
  31         progress_update = 1;
  32 }
  33
  34 static void set_progress_signal(void)
  35 {
  36         struct sigaction sa;
  37         struct itimerval v;
  38
  39         progress_update = 0;
  40
  41         memset(&sa, 0, sizeof(sa));
  42         sa.sa_handler = progress_interval;
  43         sigemptyset(&sa.sa_mask);
  44         sa.sa_flags = SA_RESTART;
  45         sigaction(SIGALRM, &sa, NULL);
  46
  47         v.it_interval.tv_sec = 1;
  48         v.it_interval.tv_usec = 0;
  49         v.it_value = v.it_interval;
  50         setitimer(ITIMER_REAL, &v, NULL);
  51 }
  52
  53 static void clear_progress_signal(void)
  54 {
  55         struct itimerval v = {{0,},};
  56         setitimer(ITIMER_REAL, &v, NULL);
  57         signal(SIGALRM, SIG_IGN);
  58         progress_update = 0;
  59 }
  60
  61 static int display(struct progress *progress, unsigned n, int done)
  62 {
  63         char *eol, *tp;
  64
  65         if (progress->delay) {
  66                 if (!progress_update || --progress->delay)
  67                         return 0;
  68                 if (progress->total) {
  69                         unsigned percent = n * 100 / progress->total;
  70                         if (percent > progress->delayed_percent_treshold) {
  71                                 /* inhibit this progress report entirely */
  72                                 clear_progress_signal();
  73                                 progress->delay = -1;
  74                                 progress->total = 0;
  75                                 return 0;
  76                         }
  77                 }
  78         }
  79
  80         progress->last_value = n;
  81         tp = (progress->throughput) ? progress->throughput->display : "";
  82         eol = done ? ", done.   \n" : "   \r";
  83         if (progress->total) {
  84                 unsigned percent = n * 100 / progress->total;
  85                 if (percent != progress->last_percent || progress_update) {
  86                         progress->last_percent = percent;
  87                         fprintf(stderr, "%s: %3u%% (%u/%u)%s%s",
  88                                 progress->title, percent, n,
  89                                 progress->total, tp, eol);
  90                         progress_update = 0;
  91                         return 1;
  92                 }
  93         } else if (progress_update) {
  94                 fprintf(stderr, "%s: %u%s%s", progress->title, n, tp, eol);
  95                 progress_update = 0;
  96                 return 1;
  97         }
  98
  99         return 0;
 100 }
 101
 102 void display_throughput(struct progress *progress, unsigned long n)
 103 {
 104         struct throughput *tp;
 105         struct timeval tv;
 106         unsigned int misecs;
 107
 108         if (!progress)
 109                 return;
 110         tp = progress->throughput;
 111
 112         gettimeofday(&tv, NULL);
 113
 114         if (!tp) {
 115                 progress->throughput = tp = calloc(1, sizeof(*tp));
 116                 if (tp)
 117                         tp->prev_tv = tv;
 118                 return;
 119         }
 120
 121         tp->count += n;
 122
 123         /*
 124          * We have x = bytes and y = microsecs.  We want z = KiB/s:
 125          *
 126          *      z = (x / 1024) / (y / 1000000)
 127          *      z = x / y * 1000000 / 1024
 128          *      z = x / (y * 1024 / 1000000)
 129          *      z = x / y'
 130          *
 131          * To simplify things we'll keep track of misecs, or 1024th of a sec
 132          * obtained with:
 133          *
 134          *      y' = y * 1024 / 1000000
 135          *      y' = y / (1000000 / 1024)
 136          *      y' = y / 977
 137          */
 138         misecs = (tv.tv_sec - tp->prev_tv.tv_sec) * 1024;
 139         misecs += (int)(tv.tv_usec - tp->prev_tv.tv_usec) / 977;
 140
 141         if (misecs > 512) {
 142                 tp->prev_tv = tv;
 143                 tp->avg_bytes += tp->count;
 144                 tp->avg_misecs += misecs;
 145                 snprintf(tp->display, sizeof(tp->display),
 146                          ", %lu KiB/s", tp->avg_bytes / tp->avg_misecs);
 147                 tp->avg_bytes -= tp->last_bytes[tp->idx];
 148                 tp->avg_misecs -= tp->last_misecs[tp->idx];
 149                 tp->last_bytes[tp->idx] = tp->count;
 150                 tp->last_misecs[tp->idx] = misecs;
 151                 tp->idx = (tp->idx + 1) % TP_IDX_MAX;
 152                 tp->count = 0;
 153         }
 154 }
 155
 156 int display_progress(struct progress *progress, unsigned n)
 157 {
 158         return progress ? display(progress, n, 0) : 0;
 159 }
 160
 161 struct progress *start_progress_delay(const char *title, unsigned total,
 162                                        unsigned percent_treshold, unsigned delay)
 163 {
 164         struct progress *progress = malloc(sizeof(*progress));
 165         if (!progress) {
 166                 /* unlikely, but here's a good fallback */
 167                 fprintf(stderr, "%s...\n", title);
 168                 return NULL;
 169         }
 170         progress->title = title;
 171         progress->total = total;
 172         progress->last_value = -1;
 173         progress->last_percent = -1;
 174         progress->delayed_percent_treshold = percent_treshold;
 175         progress->delay = delay;
 176         progress->throughput = NULL;
 177         set_progress_signal();
 178         return progress;
 179 }
 180
 181 struct progress *start_progress(const char *title, unsigned total)
 182 {
 183         return start_progress_delay(title, total, 0, 0);
 184 }
 185
 186 void stop_progress(struct progress **p_progress)
 187 {
 188         struct progress *progress = *p_progress;
 189         if (!progress)
 190                 return;
 191         *p_progress = NULL;
 192         if (progress->last_value != -1) {
 193                 /* Force the last update */
 194                 progress_update = 1;
 195                 display(progress, progress->last_value, 1);
 196         }
 197         clear_progress_signal();
 198         free(progress->throughput);
 199         free(progress);
 200 }