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/osdep.h"
  26 #include "qemu-common.h"
  27
  28 struct progress_state {
  29     float current;
  30     float last_print;
  31     float min_skip;
  32     void (*print)(void);
  33     void (*end)(void);
  34 };
  35
  36 static struct progress_state state;
  37 static volatile sig_atomic_t print_pending;
  38
  39 /*
  40  * Simple progress print function.
  41  * @percent relative percent of current operation
  42  * @max percent of total operation
  43  */
  44 static void progress_simple_print(void)
  45 {
  46     printf("    (%3.2f/100%%)\r", state.current);
  47     fflush(stdout);
  48 }
  49
  50 static void progress_simple_end(void)
  51 {
  52     printf("\n");
  53 }
  54
  55 static void progress_simple_init(void)
  56 {
  57     state.print = progress_simple_print;
  58     state.end = progress_simple_end;
  59 }
  60
  61 #ifdef CONFIG_POSIX
  62 static void sigusr_print(int signal)
  63 {
  64     print_pending = 1;
  65 }
  66 #endif
  67
  68 static void progress_dummy_print(void)
  69 {
  70     if (print_pending) {
  71         fprintf(stderr, "    (%3.2f/100%%)\n", state.current);
  72         print_pending = 0;
  73     }
  74 }
  75
  76 static void progress_dummy_end(void)
  77 {
  78 }
  79
  80 static void progress_dummy_init(void)
  81 {
  82 #ifdef CONFIG_POSIX
  83     struct sigaction action;
  84     sigset_t set;
  85
  86     memset(&action, 0, sizeof(action));
  87     sigfillset(&action.sa_mask);
  88     action.sa_handler = sigusr_print;
  89     action.sa_flags = 0;
  90     sigaction(SIGUSR1, &action, NULL);
  91
  92     /*
  93      * SIGUSR1 is SIG_IPI and gets blocked in qemu_init_main_loop(). In the
  94      * tools that use the progress report SIGUSR1 isn't used in this meaning
  95      * and instead should print the progress, so reenable it.
  96      */
  97     sigemptyset(&set);
  98     sigaddset(&set, SIGUSR1);
  99     pthread_sigmask(SIG_UNBLOCK, &set, NULL);
 100 #endif
 101
 102     state.print = progress_dummy_print;
 103     state.end = progress_dummy_end;
 104 }
 105
 106 /*
 107  * Initialize progress reporting.
 108  * If @enabled is false, actual reporting is suppressed.  The user can
 109  * still trigger a report by sending a SIGUSR1.
 110  * Reports are also suppressed unless we've had at least @min_skip
 111  * percent progress since the last report.
 112  */
 113 void qemu_progress_init(int enabled, float min_skip)
 114 {
 115     state.min_skip = min_skip;
 116     if (enabled) {
 117         progress_simple_init();
 118     } else {
 119         progress_dummy_init();
 120     }
 121 }
 122
 123 void qemu_progress_end(void)
 124 {
 125     state.end();
 126 }
 127
 128 /*
 129  * Report progress.
 130  * @delta is how much progress we made.
 131  * If @max is zero, @delta is an absolut value of the total job done.
 132  * Else, @delta is a progress delta since the last call, as a fraction
 133  * of @max.  I.e. the delta is @delta * @max / 100. This allows
 134  * relative accounting of functions which may be a different fraction of
 135  * the full job, depending on the context they are called in. I.e.
 136  * a function might be considered 40% of the full job if used from
 137  * bdrv_img_create() but only 20% if called from img_convert().
 138  */
 139 void qemu_progress_print(float delta, int max)
 140 {
 141     float current;
 142
 143     if (max == 0) {
 144         current = delta;
 145     } else {
 146         current = state.current + delta / 100 * max;
 147     }
 148     if (current > 100) {
 149         current = 100;
 150     }
 151     state.current = current;
 152
 153     if (current > (state.last_print + state.min_skip) ||
 154         current < (state.last_print - state.min_skip) ||
 155         current == 100 || current == 0) {
 156         state.last_print = state.current;
 157         state.print();
 158     }
 159 }