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 "osdep.h"
  27 #include "sysemu.h"
  28 #include <stdio.h>
  29 #include <signal.h>
  30
  31 struct progress_state {
  32     float current;
  33     float last_print;
  34     float min_skip;
  35     void (*print)(void);
  36     void (*end)(void);
  37 };
  38
  39 static struct progress_state state;
  40 static volatile sig_atomic_t print_pending;
  41
  42 /*
  43  * Simple progress print function.
  44  * @percent relative percent of current operation
  45  * @max percent of total operation
  46  */
  47 static void progress_simple_print(void)
  48 {
  49     printf("    (%3.2f/100%%)\r", state.current);
  50     fflush(stdout);
  51 }
  52
  53 static void progress_simple_end(void)
  54 {
  55     printf("\n");
  56 }
  57
  58 static void progress_simple_init(void)
  59 {
  60     state.print = progress_simple_print;
  61     state.end = progress_simple_end;
  62 }
  63
  64 #ifdef CONFIG_POSIX
  65 static void sigusr_print(int signal)
  66 {
  67     print_pending = 1;
  68 }
  69 #endif
  70
  71 static void progress_dummy_print(void)
  72 {
  73     if (print_pending) {
  74         fprintf(stderr, "    (%3.2f/100%%)\n", state.current);
  75         print_pending = 0;
  76     }
  77 }
  78
  79 static void progress_dummy_end(void)
  80 {
  81 }
  82
  83 static void progress_dummy_init(void)
  84 {
  85 #ifdef CONFIG_POSIX
  86     struct sigaction action;
  87
  88     memset(&action, 0, sizeof(action));
  89     sigfillset(&action.sa_mask);
  90     action.sa_handler = sigusr_print;
  91     action.sa_flags = 0;
  92     sigaction(SIGUSR1, &action, NULL);
  93 #endif
  94
  95     state.print = progress_dummy_print;
  96     state.end = progress_dummy_end;
  97 }
  98
  99 /*
 100  * Initialize progress reporting.
 101  * If @enabled is false, actual reporting is suppressed.  The user can
 102  * still trigger a report by sending a SIGUSR1.
 103  * Reports are also suppressed unless we've had at least @min_skip
 104  * percent progress since the last report.
 105  */
 106 void qemu_progress_init(int enabled, float min_skip)
 107 {
 108     state.min_skip = min_skip;
 109     if (enabled) {
 110         progress_simple_init();
 111     } else {
 112         progress_dummy_init();
 113     }
 114 }
 115
 116 void qemu_progress_end(void)
 117 {
 118     state.end();
 119 }
 120
 121 /*
 122  * Report progress.
 123  * @delta is how much progress we made.
 124  * If @max is zero, @delta is an absolut value of the total job done.
 125  * Else, @delta is a progress delta since the last call, as a fraction
 126  * of @max.  I.e. the delta is @delta * @max / 100. This allows
 127  * relative accounting of functions which may be a different fraction of
 128  * the full job, depending on the context they are called in. I.e.
 129  * a function might be considered 40% of the full job if used from
 130  * bdrv_img_create() but only 20% if called from img_convert().
 131  */
 132 void qemu_progress_print(float delta, int max)
 133 {
 134     float current;
 135
 136     if (max == 0) {
 137         current = delta;
 138     } else {
 139         current = state.current + delta / 100 * max;
 140     }
 141     if (current > 100) {
 142         current = 100;
 143     }
 144     state.current = current;
 145
 146     if (current > (state.last_print + state.min_skip) ||
 147         (current == 100) || (current == 0)) {
 148         state.last_print = state.current;
 149         state.print();
 150     }
 151 }