Documentation/Makefile: fix spaces around assignments
[git] / progress.c
1 /*
2  * Simple text-based progress display module for GIT
3  *
4  * Copyright (c) 2007 by Nicolas Pitre <nico@fluxnic.net>
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 #include "strbuf.h"
14
15 #define TP_IDX_MAX      8
16
17 struct throughput {
18         off_t curr_total;
19         off_t prev_total;
20         struct timeval prev_tv;
21         unsigned int avg_bytes;
22         unsigned int avg_misecs;
23         unsigned int last_bytes[TP_IDX_MAX];
24         unsigned int last_misecs[TP_IDX_MAX];
25         unsigned int idx;
26         char display[32];
27 };
28
29 struct progress {
30         const char *title;
31         int last_value;
32         unsigned total;
33         unsigned last_percent;
34         unsigned delay;
35         unsigned delayed_percent_treshold;
36         struct throughput *throughput;
37 };
38
39 static volatile sig_atomic_t progress_update;
40
41 static void progress_interval(int signum)
42 {
43         progress_update = 1;
44 }
45
46 static void set_progress_signal(void)
47 {
48         struct sigaction sa;
49         struct itimerval v;
50
51         progress_update = 0;
52
53         memset(&sa, 0, sizeof(sa));
54         sa.sa_handler = progress_interval;
55         sigemptyset(&sa.sa_mask);
56         sa.sa_flags = SA_RESTART;
57         sigaction(SIGALRM, &sa, NULL);
58
59         v.it_interval.tv_sec = 1;
60         v.it_interval.tv_usec = 0;
61         v.it_value = v.it_interval;
62         setitimer(ITIMER_REAL, &v, NULL);
63 }
64
65 static void clear_progress_signal(void)
66 {
67         struct itimerval v = {{0,},};
68         setitimer(ITIMER_REAL, &v, NULL);
69         signal(SIGALRM, SIG_IGN);
70         progress_update = 0;
71 }
72
73 static int display(struct progress *progress, unsigned n, const char *done)
74 {
75         const char *eol, *tp;
76
77         if (progress->delay) {
78                 if (!progress_update || --progress->delay)
79                         return 0;
80                 if (progress->total) {
81                         unsigned percent = n * 100 / progress->total;
82                         if (percent > progress->delayed_percent_treshold) {
83                                 /* inhibit this progress report entirely */
84                                 clear_progress_signal();
85                                 progress->delay = -1;
86                                 progress->total = 0;
87                                 return 0;
88                         }
89                 }
90         }
91
92         progress->last_value = n;
93         tp = (progress->throughput) ? progress->throughput->display : "";
94         eol = done ? done : "   \r";
95         if (progress->total) {
96                 unsigned percent = n * 100 / progress->total;
97                 if (percent != progress->last_percent || progress_update) {
98                         progress->last_percent = percent;
99                         fprintf(stderr, "%s: %3u%% (%u/%u)%s%s",
100                                 progress->title, percent, n,
101                                 progress->total, tp, eol);
102                         fflush(stderr);
103                         progress_update = 0;
104                         return 1;
105                 }
106         } else if (progress_update) {
107                 fprintf(stderr, "%s: %u%s%s", progress->title, n, tp, eol);
108                 fflush(stderr);
109                 progress_update = 0;
110                 return 1;
111         }
112
113         return 0;
114 }
115
116 static void throughput_string(struct strbuf *buf, off_t total,
117                               unsigned int rate)
118 {
119         strbuf_addstr(buf, ", ");
120         strbuf_humanise_bytes(buf, total);
121         strbuf_addstr(buf, " | ");
122         strbuf_humanise_bytes(buf, rate * 1024);
123         strbuf_addstr(buf, "/s");
124 }
125
126 void display_throughput(struct progress *progress, off_t total)
127 {
128         struct throughput *tp;
129         struct timeval tv;
130         unsigned int misecs;
131
132         if (!progress)
133                 return;
134         tp = progress->throughput;
135
136         gettimeofday(&tv, NULL);
137
138         if (!tp) {
139                 progress->throughput = tp = calloc(1, sizeof(*tp));
140                 if (tp) {
141                         tp->prev_total = tp->curr_total = total;
142                         tp->prev_tv = tv;
143                 }
144                 return;
145         }
146         tp->curr_total = total;
147
148         /*
149          * We have x = bytes and y = microsecs.  We want z = KiB/s:
150          *
151          *      z = (x / 1024) / (y / 1000000)
152          *      z = x / y * 1000000 / 1024
153          *      z = x / (y * 1024 / 1000000)
154          *      z = x / y'
155          *
156          * To simplify things we'll keep track of misecs, or 1024th of a sec
157          * obtained with:
158          *
159          *      y' = y * 1024 / 1000000
160          *      y' = y / (1000000 / 1024)
161          *      y' = y / 977
162          */
163         misecs = (tv.tv_sec - tp->prev_tv.tv_sec) * 1024;
164         misecs += (int)(tv.tv_usec - tp->prev_tv.tv_usec) / 977;
165
166         if (misecs > 512) {
167                 struct strbuf buf = STRBUF_INIT;
168                 unsigned int count, rate;
169
170                 count = total - tp->prev_total;
171                 tp->prev_total = total;
172                 tp->prev_tv = tv;
173                 tp->avg_bytes += count;
174                 tp->avg_misecs += misecs;
175                 rate = tp->avg_bytes / tp->avg_misecs;
176                 tp->avg_bytes -= tp->last_bytes[tp->idx];
177                 tp->avg_misecs -= tp->last_misecs[tp->idx];
178                 tp->last_bytes[tp->idx] = count;
179                 tp->last_misecs[tp->idx] = misecs;
180                 tp->idx = (tp->idx + 1) % TP_IDX_MAX;
181
182                 throughput_string(&buf, total, rate);
183                 strncpy(tp->display, buf.buf, sizeof(tp->display));
184                 strbuf_release(&buf);
185                 if (progress->last_value != -1 && progress_update)
186                         display(progress, progress->last_value, NULL);
187         }
188 }
189
190 int display_progress(struct progress *progress, unsigned n)
191 {
192         return progress ? display(progress, n, NULL) : 0;
193 }
194
195 struct progress *start_progress_delay(const char *title, unsigned total,
196                                        unsigned percent_treshold, unsigned delay)
197 {
198         struct progress *progress = malloc(sizeof(*progress));
199         if (!progress) {
200                 /* unlikely, but here's a good fallback */
201                 fprintf(stderr, "%s...\n", title);
202                 fflush(stderr);
203                 return NULL;
204         }
205         progress->title = title;
206         progress->total = total;
207         progress->last_value = -1;
208         progress->last_percent = -1;
209         progress->delayed_percent_treshold = percent_treshold;
210         progress->delay = delay;
211         progress->throughput = NULL;
212         set_progress_signal();
213         return progress;
214 }
215
216 struct progress *start_progress(const char *title, unsigned total)
217 {
218         return start_progress_delay(title, total, 0, 0);
219 }
220
221 void stop_progress(struct progress **p_progress)
222 {
223         stop_progress_msg(p_progress, "done");
224 }
225
226 void stop_progress_msg(struct progress **p_progress, const char *msg)
227 {
228         struct progress *progress = *p_progress;
229         if (!progress)
230                 return;
231         *p_progress = NULL;
232         if (progress->last_value != -1) {
233                 /* Force the last update */
234                 char buf[128], *bufp;
235                 size_t len = strlen(msg) + 5;
236                 struct throughput *tp = progress->throughput;
237
238                 bufp = (len < sizeof(buf)) ? buf : xmalloc(len + 1);
239                 if (tp) {
240                         struct strbuf strbuf = STRBUF_INIT;
241                         unsigned int rate = !tp->avg_misecs ? 0 :
242                                         tp->avg_bytes / tp->avg_misecs;
243                         throughput_string(&strbuf, tp->curr_total, rate);
244                         strncpy(tp->display, strbuf.buf, sizeof(tp->display));
245                         strbuf_release(&strbuf);
246                 }
247                 progress_update = 1;
248                 sprintf(bufp, ", %s.\n", msg);
249                 display(progress, progress->last_value, bufp);
250                 if (buf != bufp)
251                         free(bufp);
252         }
253         clear_progress_signal();
254         free(progress->throughput);
255         free(progress);
256 }