Documentation: fix git-clone manpage not to refer to itself
[git] / progress.c
1 /*
2  * Simple text-based progress display module for GIT
3  *
4  * Copyright (c) 2007 by Nicolas Pitre <nico@cam.org>
5  *
6  * This code is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License version 2 as
8  * published by the Free Software Foundation.
9  */
10
11 #include "git-compat-util.h"
12 #include "progress.h"
13
14 #define TP_IDX_MAX      8
15
16 struct throughput {
17         off_t curr_total;
18         off_t prev_total;
19         struct timeval prev_tv;
20         unsigned int avg_bytes;
21         unsigned int avg_misecs;
22         unsigned int last_bytes[TP_IDX_MAX];
23         unsigned int last_misecs[TP_IDX_MAX];
24         unsigned int idx;
25         char display[32];
26 };
27
28 struct progress {
29         const char *title;
30         int last_value;
31         unsigned total;
32         unsigned last_percent;
33         unsigned delay;
34         unsigned delayed_percent_treshold;
35         struct throughput *throughput;
36 };
37
38 static volatile sig_atomic_t progress_update;
39
40 static void progress_interval(int signum)
41 {
42         progress_update = 1;
43 }
44
45 static void set_progress_signal(void)
46 {
47         struct sigaction sa;
48         struct itimerval v;
49
50         progress_update = 0;
51
52         memset(&sa, 0, sizeof(sa));
53         sa.sa_handler = progress_interval;
54         sigemptyset(&sa.sa_mask);
55         sa.sa_flags = SA_RESTART;
56         sigaction(SIGALRM, &sa, NULL);
57
58         v.it_interval.tv_sec = 1;
59         v.it_interval.tv_usec = 0;
60         v.it_value = v.it_interval;
61         setitimer(ITIMER_REAL, &v, NULL);
62 }
63
64 static void clear_progress_signal(void)
65 {
66         struct itimerval v = {{0,},};
67         setitimer(ITIMER_REAL, &v, NULL);
68         signal(SIGALRM, SIG_IGN);
69         progress_update = 0;
70 }
71
72 static int display(struct progress *progress, unsigned n, const char *done)
73 {
74         const char *eol, *tp;
75
76         if (progress->delay) {
77                 if (!progress_update || --progress->delay)
78                         return 0;
79                 if (progress->total) {
80                         unsigned percent = n * 100 / progress->total;
81                         if (percent > progress->delayed_percent_treshold) {
82                                 /* inhibit this progress report entirely */
83                                 clear_progress_signal();
84                                 progress->delay = -1;
85                                 progress->total = 0;
86                                 return 0;
87                         }
88                 }
89         }
90
91         progress->last_value = n;
92         tp = (progress->throughput) ? progress->throughput->display : "";
93         eol = done ? done : "   \r";
94         if (progress->total) {
95                 unsigned percent = n * 100 / progress->total;
96                 if (percent != progress->last_percent || progress_update) {
97                         progress->last_percent = percent;
98                         fprintf(stderr, "%s: %3u%% (%u/%u)%s%s",
99                                 progress->title, percent, n,
100                                 progress->total, tp, eol);
101                         progress_update = 0;
102                         return 1;
103                 }
104         } else if (progress_update) {
105                 fprintf(stderr, "%s: %u%s%s", progress->title, n, tp, eol);
106                 progress_update = 0;
107                 return 1;
108         }
109
110         return 0;
111 }
112
113 static void throughput_string(struct throughput *tp, off_t total,
114                               unsigned int rate)
115 {
116         int l = sizeof(tp->display);
117         if (total > 1 << 30) {
118                 l -= snprintf(tp->display, l, ", %u.%2.2u GiB",
119                               (int)(total >> 30),
120                               (int)(total & ((1 << 30) - 1)) / 10737419);
121         } else if (total > 1 << 20) {
122                 l -= snprintf(tp->display, l, ", %u.%2.2u MiB",
123                               (int)(total >> 20),
124                               ((int)(total & ((1 << 20) - 1)) * 100) >> 20);
125         } else if (total > 1 << 10) {
126                 l -= snprintf(tp->display, l, ", %u.%2.2u KiB",
127                               (int)(total >> 10),
128                               ((int)(total & ((1 << 10) - 1)) * 100) >> 10);
129         } else {
130                 l -= snprintf(tp->display, l, ", %u bytes", (int)total);
131         }
132         if (rate)
133                 snprintf(tp->display + sizeof(tp->display) - l, l,
134                          " | %u KiB/s", rate);
135 }
136
137 void display_throughput(struct progress *progress, off_t total)
138 {
139         struct throughput *tp;
140         struct timeval tv;
141         unsigned int misecs;
142
143         if (!progress)
144                 return;
145         tp = progress->throughput;
146
147         gettimeofday(&tv, NULL);
148
149         if (!tp) {
150                 progress->throughput = tp = calloc(1, sizeof(*tp));
151                 if (tp) {
152                         tp->prev_total = tp->curr_total = total;
153                         tp->prev_tv = tv;
154                 }
155                 return;
156         }
157         tp->curr_total = total;
158
159         /*
160          * We have x = bytes and y = microsecs.  We want z = KiB/s:
161          *
162          *      z = (x / 1024) / (y / 1000000)
163          *      z = x / y * 1000000 / 1024
164          *      z = x / (y * 1024 / 1000000)
165          *      z = x / y'
166          *
167          * To simplify things we'll keep track of misecs, or 1024th of a sec
168          * obtained with:
169          *
170          *      y' = y * 1024 / 1000000
171          *      y' = y / (1000000 / 1024)
172          *      y' = y / 977
173          */
174         misecs = (tv.tv_sec - tp->prev_tv.tv_sec) * 1024;
175         misecs += (int)(tv.tv_usec - tp->prev_tv.tv_usec) / 977;
176
177         if (misecs > 512) {
178                 unsigned int count, rate;
179
180                 count = total - tp->prev_total;
181                 tp->prev_total = total;
182                 tp->prev_tv = tv;
183                 tp->avg_bytes += count;
184                 tp->avg_misecs += misecs;
185                 rate = tp->avg_bytes / tp->avg_misecs;
186                 tp->avg_bytes -= tp->last_bytes[tp->idx];
187                 tp->avg_misecs -= tp->last_misecs[tp->idx];
188                 tp->last_bytes[tp->idx] = count;
189                 tp->last_misecs[tp->idx] = misecs;
190                 tp->idx = (tp->idx + 1) % TP_IDX_MAX;
191
192                 throughput_string(tp, total, rate);
193                 if (progress->last_value != -1 && progress_update)
194                         display(progress, progress->last_value, NULL);
195         }
196 }
197
198 int display_progress(struct progress *progress, unsigned n)
199 {
200         return progress ? display(progress, n, NULL) : 0;
201 }
202
203 struct progress *start_progress_delay(const char *title, unsigned total,
204                                        unsigned percent_treshold, unsigned delay)
205 {
206         struct progress *progress = malloc(sizeof(*progress));
207         if (!progress) {
208                 /* unlikely, but here's a good fallback */
209                 fprintf(stderr, "%s...\n", title);
210                 return NULL;
211         }
212         progress->title = title;
213         progress->total = total;
214         progress->last_value = -1;
215         progress->last_percent = -1;
216         progress->delayed_percent_treshold = percent_treshold;
217         progress->delay = delay;
218         progress->throughput = NULL;
219         set_progress_signal();
220         return progress;
221 }
222
223 struct progress *start_progress(const char *title, unsigned total)
224 {
225         return start_progress_delay(title, total, 0, 0);
226 }
227
228 void stop_progress(struct progress **p_progress)
229 {
230         stop_progress_msg(p_progress, "done");
231 }
232
233 void stop_progress_msg(struct progress **p_progress, const char *msg)
234 {
235         struct progress *progress = *p_progress;
236         if (!progress)
237                 return;
238         *p_progress = NULL;
239         if (progress->last_value != -1) {
240                 /* Force the last update */
241                 char buf[strlen(msg) + 5];
242                 struct throughput *tp = progress->throughput;
243                 if (tp) {
244                         unsigned int rate = !tp->avg_misecs ? 0 :
245                                         tp->avg_bytes / tp->avg_misecs;
246                         throughput_string(tp, tp->curr_total, rate);
247                 }
248                 progress_update = 1;
249                 sprintf(buf, ", %s.\n", msg);
250                 display(progress, progress->last_value, buf);
251         }
252         clear_progress_signal();
253         free(progress->throughput);
254         free(progress);
255 }