qemu-progress.c

   1 /*
   2  * QEMU progress printing utility functions
   3  *
   4  * Copyright (C) 2011 Jes Sorensen <Jes.Sorensen@redhat.com>
   5  *
   6  * Permission is hereby granted, free of charge, to any person obtaining a copy
   7  * of this software and associated documentation files (the "Software"), to deal
   8  * in the Software without restriction, including without limitation the rights
   9  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  10  * copies of the Software, and to permit persons to whom the Software is
  11  * furnished to do so, subject to the following conditions:
  12  *
  13  * The above copyright notice and this permission notice shall be included in
  14  * all copies or substantial portions of the Software.
  15  *
  16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
  19  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  21  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  22  * THE SOFTWARE.
  23  */
  24
  25 #include "qemu-common.h"
  26 #include "qemu/osdep.h"
  27 #include "sysemu/sysemu.h"
  28 #include <stdio.h>
  29
  30 struct progress_state {
  31     float current;
  32     float last_print;
  33     float min_skip;
  34     void (*print)(void);
  35     void (*end)(void);
  36 };
  37
  38 static struct progress_state state;
  39 static volatile sig_atomic_t print_pending;
  40
  41 /*
  42  * Simple progress print function.
  43  * @percent relative percent of current operation
  44  * @max percent of total operation
  45  */
  46 static void progress_simple_print(void)
  47 {
  48     printf("    (%3.2f/100%%)\r", state.current);
  49     fflush(stdout);
  50 }
  51
  52 static void progress_simple_end(void)
  53 {
  54     printf("\n");
  55 }
  56
  57 static void progress_simple_init(void)
  58 {
  59     state.print = progress_simple_print;
  60     state.end = progress_simple_end;
  61 }
  62
  63 #ifdef CONFIG_POSIX
  64 static void sigusr_print(int signal)
  65 {
  66     print_pending = 1;
  67 }
  68 #endif
  69
  70 static void progress_dummy_print(void)
  71 {
  72     if (print_pending) {
  73         fprintf(stderr, "    (%3.2f/100%%)\n", state.current);
  74         print_pending = 0;
  75     }
  76 }
  77
  78 static void progress_dummy_end(void)
  79 {
  80 }
  81
  82 static void progress_dummy_init(void)
  83 {
  84 #ifdef CONFIG_POSIX
  85     struct sigaction action;
  86
  87     memset(&action, 0, sizeof(action));
  88     sigfillset(&action.sa_mask);
  89     action.sa_handler = sigusr_print;
  90     action.sa_flags = 0;
  91     sigaction(SIGUSR1, &action, NULL);
  92 #endif
  93
  94     state.print = progress_dummy_print;
  95     state.end = progress_dummy_end;
  96 }
  97
  98 /*
  99  * Initialize progress reporting.
 100  * If @enabled is false, actual reporting is suppressed.  The user can
 101  * still trigger a report by sending a SIGUSR1.
 102  * Reports are also suppressed unless we've had at least @min_skip
 103  * percent progress since the last report.
 104  */
 105 void qemu_progress_init(int enabled, float min_skip)
 106 {
 107     state.min_skip = min_skip;
 108     if (enabled) {
 109         progress_simple_init();
 110     } else {
 111         progress_dummy_init();
 112     }
 113 }
 114
 115 void qemu_progress_end(void)
 116 {
 117     state.end();
 118 }
 119
 120 /*
 121  * Report progress.
 122  * @delta is how much progress we made.
 123  * If @max is zero, @delta is an absolut value of the total job done.
 124  * Else, @delta is a progress delta since the last call, as a fraction
 125  * of @max.  I.e. the delta is @delta * @max / 100. This allows
 126  * relative accounting of functions which may be a different fraction of
 127  * the full job, depending on the context they are called in. I.e.
 128  * a function might be considered 40% of the full job if used from
 129  * bdrv_img_create() but only 20% if called from img_convert().
 130  */
 131 void qemu_progress_print(float delta, int max)
 132 {
 133     float current;
 134
 135     if (max == 0) {
 136         current = delta;
 137     } else {
 138         current = state.current + delta / 100 * max;
 139     }
 140     if (current > 100) {
 141         current = 100;
 142     }
 143     state.current = current;
 144
 145     if (current > (state.last_print + state.min_skip) ||
 146         (current == 100) || (current == 0)) {
 147         state.last_print = state.current;
 148         state.print();
 149     }
 150 }