util/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 <stdio.h>
  28
  29 struct progress_state {
  30     float current;
  31     float last_print;
  32     float min_skip;
  33     void (*print)(void);
  34     void (*end)(void);
  35 };
  36
  37 static struct progress_state state;
  38 static volatile sig_atomic_t print_pending;
  39
  40 /*
  41  * Simple progress print function.
  42  * @percent relative percent of current operation
  43  * @max percent of total operation
  44  */
  45 static void progress_simple_print(void)
  46 {
  47     printf("    (%3.2f/100%%)\r", state.current);
  48     fflush(stdout);
  49 }
  50
  51 static void progress_simple_end(void)
  52 {
  53     printf("\n");
  54 }
  55
  56 static void progress_simple_init(void)
  57 {
  58     state.print = progress_simple_print;
  59     state.end = progress_simple_end;
  60 }
  61
  62 #ifdef CONFIG_POSIX
  63 static void sigusr_print(int signal)
  64 {
  65     print_pending = 1;
  66 }
  67 #endif
  68
  69 static void progress_dummy_print(void)
  70 {
  71     if (print_pending) {
  72         fprintf(stderr, "    (%3.2f/100%%)\n", state.current);
  73         print_pending = 0;
  74     }
  75 }
  76
  77 static void progress_dummy_end(void)
  78 {
  79 }
  80
  81 static void progress_dummy_init(void)
  82 {
  83 #ifdef CONFIG_POSIX
  84     struct sigaction action;
  85     sigset_t set;
  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
  93     /*
  94      * SIGUSR1 is SIG_IPI and gets blocked in qemu_init_main_loop(). In the
  95      * tools that use the progress report SIGUSR1 isn't used in this meaning
  96      * and instead should print the progress, so reenable it.
  97      */
  98     sigemptyset(&set);
  99     sigaddset(&set, SIGUSR1);
 100     pthread_sigmask(SIG_UNBLOCK, &set, NULL);
 101 #endif
 102
 103     state.print = progress_dummy_print;
 104     state.end = progress_dummy_end;
 105 }
 106
 107 /*
 108  * Initialize progress reporting.
 109  * If @enabled is false, actual reporting is suppressed.  The user can
 110  * still trigger a report by sending a SIGUSR1.
 111  * Reports are also suppressed unless we've had at least @min_skip
 112  * percent progress since the last report.
 113  */
 114 void qemu_progress_init(int enabled, float min_skip)
 115 {
 116     state.min_skip = min_skip;
 117     if (enabled) {
 118         progress_simple_init();
 119     } else {
 120         progress_dummy_init();
 121     }
 122 }
 123
 124 void qemu_progress_end(void)
 125 {
 126     state.end();
 127 }
 128
 129 /*
 130  * Report progress.
 131  * @delta is how much progress we made.
 132  * If @max is zero, @delta is an absolut value of the total job done.
 133  * Else, @delta is a progress delta since the last call, as a fraction
 134  * of @max.  I.e. the delta is @delta * @max / 100. This allows
 135  * relative accounting of functions which may be a different fraction of
 136  * the full job, depending on the context they are called in. I.e.
 137  * a function might be considered 40% of the full job if used from
 138  * bdrv_img_create() but only 20% if called from img_convert().
 139  */
 140 void qemu_progress_print(float delta, int max)
 141 {
 142     float current;
 143
 144     if (max == 0) {
 145         current = delta;
 146     } else {
 147         current = state.current + delta / 100 * max;
 148     }
 149     if (current > 100) {
 150         current = 100;
 151     }
 152     state.current = current;
 153
 154     if (current > (state.last_print + state.min_skip) ||
 155         current < (state.last_print - state.min_skip) ||
 156         current == 100 || current == 0) {
 157         state.last_print = state.current;
 158         state.print();
 159     }
 160 }