progress.c

   1 #include "git-compat-util.h"
   2 #include "progress.h"
   3
   4 struct progress {
   5         const char *title;
   6         int last_value;
   7         unsigned total;
   8         unsigned last_percent;
   9         unsigned delay;
  10         unsigned delayed_percent_treshold;
  11 };
  12
  13 static volatile sig_atomic_t progress_update;
  14
  15 static void progress_interval(int signum)
  16 {
  17         progress_update = 1;
  18 }
  19
  20 static void set_progress_signal(void)
  21 {
  22         struct sigaction sa;
  23         struct itimerval v;
  24
  25         progress_update = 0;
  26
  27         memset(&sa, 0, sizeof(sa));
  28         sa.sa_handler = progress_interval;
  29         sigemptyset(&sa.sa_mask);
  30         sa.sa_flags = SA_RESTART;
  31         sigaction(SIGALRM, &sa, NULL);
  32
  33         v.it_interval.tv_sec = 1;
  34         v.it_interval.tv_usec = 0;
  35         v.it_value = v.it_interval;
  36         setitimer(ITIMER_REAL, &v, NULL);
  37 }
  38
  39 static void clear_progress_signal(void)
  40 {
  41         struct itimerval v = {{0,},};
  42         setitimer(ITIMER_REAL, &v, NULL);
  43         signal(SIGALRM, SIG_IGN);
  44         progress_update = 0;
  45 }
  46
  47 static int display(struct progress *progress, unsigned n, int done)
  48 {
  49         char *eol;
  50
  51         if (progress->delay) {
  52                 if (!progress_update || --progress->delay)
  53                         return 0;
  54                 if (progress->total) {
  55                         unsigned percent = n * 100 / progress->total;
  56                         if (percent > progress->delayed_percent_treshold) {
  57                                 /* inhibit this progress report entirely */
  58                                 clear_progress_signal();
  59                                 progress->delay = -1;
  60                                 progress->total = 0;
  61                                 return 0;
  62                         }
  63                 }
  64         }
  65
  66         progress->last_value = n;
  67         eol = done ? ", done.   \n" : "   \r";
  68         if (progress->total) {
  69                 unsigned percent = n * 100 / progress->total;
  70                 if (percent != progress->last_percent || progress_update) {
  71                         progress->last_percent = percent;
  72                         fprintf(stderr, "%s: %3u%% (%u/%u)%s", progress->title,
  73                                 percent, n, progress->total, eol);
  74                         progress_update = 0;
  75                         return 1;
  76                 }
  77         } else if (progress_update) {
  78                 fprintf(stderr, "%s: %u%s", progress->title, n, eol);
  79                 progress_update = 0;
  80                 return 1;
  81         }
  82
  83         return 0;
  84 }
  85
  86 int display_progress(struct progress *progress, unsigned n)
  87 {
  88         return progress ? display(progress, n, 0) : 0;
  89 }
  90
  91 struct progress *start_progress_delay(const char *title, unsigned total,
  92                                        unsigned percent_treshold, unsigned delay)
  93 {
  94         struct progress *progress = malloc(sizeof(*progress));
  95         if (!progress) {
  96                 /* unlikely, but here's a good fallback */
  97                 fprintf(stderr, "%s...\n", title);
  98                 return NULL;
  99         }
 100         progress->title = title;
 101         progress->total = total;
 102         progress->last_value = -1;
 103         progress->last_percent = -1;
 104         progress->delayed_percent_treshold = percent_treshold;
 105         progress->delay = delay;
 106         set_progress_signal();
 107         return progress;
 108 }
 109
 110 struct progress *start_progress(const char *title, unsigned total)
 111 {
 112         return start_progress_delay(title, total, 0, 0);
 113 }
 114
 115 void stop_progress(struct progress **p_progress)
 116 {
 117         struct progress *progress = *p_progress;
 118         if (!progress)
 119                 return;
 120         *p_progress = NULL;
 121         if (progress->last_value != -1) {
 122                 /* Force the last update */
 123                 progress_update = 1;
 124                 display(progress, progress->last_value, 1);
 125         }
 126         clear_progress_signal();
 127         free(progress);
 128 }