1 /**
2 * hiccup.c
3 * Written by Michael Barker and released to the public domain,
4 * as explained at http://creativecommons.org/publicdomain/zero/1.0/
5 */
6
7 #include <stdint.h>
8 #include <stdbool.h>
9 #include <stdio.h>
10 #include <pthread.h>
11 #include <sys/timerfd.h>
12 #include <poll.h>
13 #include <string.h>
14 #include <signal.h>
15 #include <ctype.h>
16 #include <stdio.h>
17 #include <stdlib.h>
18 #include <unistd.h>
19
20 #include <hdr_histogram.h>
21 #include <hdr_histogram_log.h>
22 #include <hdr_interval_recorder.h>
23 #include <hdr_time.h>
24
diff(struct timespec t0, struct timespec t1)25 static int64_t diff(struct timespec t0, struct timespec t1)
26 {
27 int64_t delta_us = 0;
28 delta_us = (t1.tv_sec - t0.tv_sec) * 1000000;
29 delta_us += (t1.tv_nsec - t0.tv_nsec) / 1000;
30
31 return delta_us;
32 }
33
record_hiccups(void* thread_context)34 static void* record_hiccups(void* thread_context)
35 {
36 struct pollfd fd;
37 struct timespec t0;
38 struct timespec t1;
39 struct itimerspec timeout;
40 struct hdr_interval_recorder* r = thread_context;
41
42 memset(&fd, 0, sizeof(struct pollfd));
43 memset(&timeout, 0, sizeof(struct itimerspec));
44 memset(&t0, 0, sizeof(struct timespec));
45 memset(&t1, 0, sizeof(struct timespec));
46
47 fd.fd = timerfd_create(CLOCK_MONOTONIC, TFD_NONBLOCK | TFD_CLOEXEC);
48 fd.events = POLLIN|POLLPRI|POLLRDHUP;
49 fd.revents = 0;
50
51 #pragma clang diagnostic push
52 #pragma clang diagnostic ignored "-Wmissing-noreturn"
53 while (true)
54 {
55 int64_t delta_us;
56
57 timeout.it_value.tv_sec = 0;
58 timeout.it_value.tv_nsec = 1000000;
59 timerfd_settime(fd.fd, 0, &timeout, NULL);
60
61 hdr_gettime(&t0);
62 poll(&fd, 1, -1);
63 hdr_gettime(&t1);
64
65 delta_us = diff(t0, t1) - 1000;
66 delta_us = delta_us < 0 ? 0 : delta_us;
67
68 hdr_interval_recorder_record_value(r, delta_us);
69 }
70 #pragma clang diagnostic pop
71
72 pthread_exit(NULL);
73 }
74
75 struct config_t
76 {
77 int interval;
78 const char* filename;
79 };
80
81 const char* USAGE =
82 "hiccup [-i <interval>] [-f <filename>]\n"
83 " interval: <number> Time in seconds between samples (default 1).\n"
84 " filename: <string> Name of the file to log to (default stdout).\n";
85
handle_opts(int argc, char** argv, struct config_t* config)86 static int handle_opts(int argc, char** argv, struct config_t* config)
87 {
88 int c;
89 int interval = 1;
90
91 while ((c = getopt(argc, argv, "i:f:")) != -1)
92 {
93 switch (c)
94 {
95 case 'h':
96 return 0;
97
98 case 'i':
99 interval = atoi(optarg);
100 if (interval < 1)
101 {
102 return 0;
103 }
104
105 break;
106 case 'f':
107 config->filename = optarg;
108 break;
109 default:
110 return 0;
111 }
112 }
113
114 config->interval = interval < 1 ? 1 : interval;
115 return 1;
116 }
117
main(int argc, char** argv)118 int main(int argc, char** argv)
119 {
120 struct timespec timestamp;
121 struct timespec start_timestamp;
122 struct timespec end_timestamp;
123 struct hdr_interval_recorder recorder;
124 struct hdr_log_writer log_writer;
125 struct config_t config;
126 struct hdr_histogram* inactive = NULL;
127 pthread_t recording_thread;
128 FILE* output = stdout;
129
130 memset(&config, 0, sizeof(struct config_t));
131 if (!handle_opts(argc, argv, &config))
132 {
133 printf("%s", USAGE);
134 return 0;
135 }
136
137 if (config.filename)
138 {
139 output = fopen(config.filename, "a+");
140 if (!output)
141 {
142 fprintf(
143 stderr, "Failed to open/create file: %s, %s",
144 config.filename, strerror(errno));
145
146 return -1;
147 }
148 }
149
150 if (0 != hdr_interval_recorder_init_all(&recorder, 1, INT64_C(24) * 60 * 60 * 1000000, 3))
151 {
152 fprintf(stderr, "%s\n", "Failed to init phaser");
153 return -1;
154 }
155
156 if (pthread_create(&recording_thread, NULL, record_hiccups, &recorder))
157 {
158 fprintf(stderr, "%s\n", "Failed to create thread");
159 return -1;
160 }
161
162 hdr_gettime(&start_timestamp);
163 hdr_getnow(×tamp);
164 hdr_log_writer_init(&log_writer);
165 hdr_log_write_header(&log_writer, output, "foobar", ×tamp);
166
167 #pragma clang diagnostic push
168 #pragma clang diagnostic ignored "-Wmissing-noreturn"
169 while (true)
170 {
171 sleep(config.interval);
172
173 inactive = hdr_interval_recorder_sample(&recorder);
174
175 hdr_gettime(&end_timestamp);
176 timestamp = start_timestamp;
177
178 hdr_gettime(&start_timestamp);
179
180 hdr_log_write(&log_writer, output, ×tamp, &end_timestamp, inactive);
181 fflush(output);
182
183 hdr_reset(inactive);
184 }
185 #pragma clang diagnostic pop
186
187 pthread_exit(NULL);
188 }
189