copy/progress.c

   1 /* NBD client library in userspace.
   2  * Copyright Red Hat
   3  *
   4  * This library is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU Lesser General Public
   6  * License as published by the Free Software Foundation; either
   7  * version 2 of the License, or (at your option) any later version.
   8  *
   9  * This library is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  * Lesser General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU Lesser General Public
  15  * License along with this library; if not, write to the Free Software
  16  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  17  */
  18
  19 #include <config.h>
  20
  21 #include <stdio.h>
  22 #include <stdlib.h>
  23 #include <stdint.h>
  24 #include <string.h>
  25 #include <fcntl.h>
  26 #include <unistd.h>
  27
  28 #include <pthread.h>
  29
  30 #include <libnbd.h>
  31
  32 #include "array-size.h"
  33
  34 #include "nbdcopy.h"
  35
  36 /* Display the progress bar. */
  37 static void
  38 do_progress_bar (off_t pos, int64_t size)
  39 {
  40   /* Note the spinner is covered with the cursor which usually makes
  41    * it appear inverse video.
  42    */
  43   static const char *spinner[] = { "▝", "▐", "▗", "▃", "▖", "▍", "▘", "▀" };
  44   static const char *spinner_100 = "█";
  45   static int spinpos = 0;
  46
  47   double frac = (double) pos / size;
  48   char msg[80];
  49   size_t n, i;
  50
  51   if (frac < 0) frac = 0; else if (frac > 1) frac = 1;
  52
  53   if (frac == 1) {
  54     snprintf (msg, sizeof msg,
  55               "%s 100%% [****************************************]\n",
  56               spinner_100);
  57     progress = false; /* Don't print any more progress bar messages. */
  58   } else {
  59     snprintf (msg, sizeof msg,
  60               "%s %3d%% [----------------------------------------]\r",
  61               spinner[spinpos], (int)(100*frac));
  62     n = strcspn (msg, "-");
  63     for (i = 0; i < 40*frac; ++i)
  64       msg[n+i] = '*';
  65     spinpos = (spinpos+1) % ARRAY_SIZE (spinner);
  66   }
  67
  68 #pragma GCC diagnostic push
  69 #pragma GCC diagnostic ignored "-Wunused-result"
  70   write (fileno (stderr), msg, strlen (msg));
  71 #pragma GCC diagnostic pop
  72 }
  73
  74 /* Machine-readable progress bar used with --progress-fd. */
  75 static void
  76 do_progress_bar_fd (off_t pos, int64_t size)
  77 {
  78   double frac = (double) pos / size;
  79   char msg[80];
  80
  81   if (frac < 0) frac = 0; else if (frac > 1) frac = 1;
  82   if (frac == 1)
  83     snprintf (msg, sizeof msg, "100/100\n");
  84   else
  85     snprintf (msg, sizeof msg, "%d/100\n", (int)(100*frac));
  86
  87 #pragma GCC diagnostic push
  88 #pragma GCC diagnostic ignored "-Wunused-result"
  89   write (progress_fd, msg, strlen (msg));
  90 #pragma GCC diagnostic pop
  91 }
  92
  93 void
  94 progress_bar (off_t pos, int64_t size)
  95 {
  96   static pthread_mutex_t lock = PTHREAD_MUTEX_INITIALIZER;
  97
  98   if (!progress)
  99     return;
 100   if (size == 0)
 101     return;
 102
 103   pthread_mutex_lock (&lock);
 104   if (progress_fd == -1)
 105     do_progress_bar (pos, size);
 106   else
 107     do_progress_bar_fd (pos, size);
 108   pthread_mutex_unlock (&lock);
 109 }