Split out fps-limit.h
authorAntonio Ospite <ospite@studenti.unina.it>
Tue, 17 Dec 2013 23:03:11 +0000 (00:03 +0100)
committerAntonio Ospite <ospite@studenti.unina.it>
Tue, 17 Dec 2013 23:03:11 +0000 (00:03 +0100)
Makefile
fps-limit.c
fps-limit.h [new file with mode: 0644]

index 961ef03..cec8b3c 100644 (file)
--- a/Makefile
+++ b/Makefile
@@ -36,6 +36,7 @@ CFLAGS += -D_POSIX_C_SOURCE=200112L
 LDLIBS += -lrt
 
 fps-limit: fps-limit.o
+fps-limit.o: fps-limit.h
 
 clean:
        rm -rf *~ *.o fps-limit
index 3ed784f..101f126 100644 (file)
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
-#include <stdio.h>
-#include <string.h>
-#include <time.h>
-
-#ifdef DEBUG
-#define dbg(...)                     \
-       do {                         \
-               printf(__VA_ARGS__); \
-               printf("\n");        \
-               fflush(stdout);      \
-       } while(0)
-#else
-#define dbg(...) do {} while(0)
-#endif
+#include "fps-limit.h"
 
 #define FPS 60
 
-#define NSEC_PER_SEC 1000000000
-
-#define timespecsub(a, b, result)                                \
-       do {                                                     \
-               (result)->tv_sec = (a)->tv_sec - (b)->tv_sec;    \
-               (result)->tv_nsec = (a)->tv_nsec - (b)->tv_nsec; \
-               if ((result)->tv_nsec < 0) {                     \
-                       --(result)->tv_sec;                      \
-                       (result)->tv_nsec += 1000000000;         \
-               }                                                \
-       } while(0)
-
-struct fps_limit_stats {
-       struct timespec time_start;
-       struct timespec time_end;
-       unsigned int fps;
-};
-
-static void fps_limit_init(struct fps_limit_stats *stats, unsigned int fps)
-{
-       memset(stats, 0, sizeof(*stats));
-
-       clock_gettime(CLOCK_MONOTONIC, &stats->time_start);
-       dbg("Init time: s: %ld, ns: %ld", stats->time_start.tv_sec, stats->time_start.tv_nsec);
-
-       stats->fps = fps;
-}
-
-static void fps_limit_sleep(struct fps_limit_stats *stats)
-{
-       struct timespec elapsed;
-
-       dbg("Start time: s: %ld, ns: %ld", stats->time_start.tv_sec, stats->time_start.tv_nsec);
-
-       clock_gettime(CLOCK_MONOTONIC, &stats->time_end);
-       dbg("End time: s: %ld, ns: %ld", stats->time_end.tv_sec, stats->time_end.tv_nsec);
-
-       timespecsub(&stats->time_end, &stats->time_start, &elapsed);
-       dbg("Elapsed s: %ld ns: %ld", elapsed.tv_sec, elapsed.tv_nsec);
-
-       if (elapsed.tv_sec == 0 && elapsed.tv_nsec < NSEC_PER_SEC / stats->fps) {
-               struct timespec remaining = {0, 0};
-
-               /* remaining delay, _relative_ to time_end */
-               remaining.tv_nsec = (NSEC_PER_SEC / stats->fps) - elapsed.tv_nsec;
-               dbg("Sleeping for: ns: %ld", remaining.tv_nsec);
-
-               clock_nanosleep(CLOCK_MONOTONIC, 0, &remaining, NULL);
-       }
-
-       /* update the stats for the next iteration */
-       clock_gettime(CLOCK_MONOTONIC, &stats->time_start);
-}
-
 int main(void)
 {
        struct fps_limit_stats stats;
diff --git a/fps-limit.h b/fps-limit.h
new file mode 100644 (file)
index 0000000..101cf1d
--- /dev/null
@@ -0,0 +1,91 @@
+/*
+ * fps-limit - Some functions to limit frames per seconds
+ *
+ * Copyright (C) 2013  Antonio Ospite <ospite@studenti.unina.it>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef FPS_LIMIT_H
+#define FPS_LIMIT_H
+
+#include <stdio.h>
+#include <string.h>
+#include <time.h>
+
+#ifdef DEBUG
+#define dbg(...)                     \
+       do {                         \
+               printf(__VA_ARGS__); \
+               printf("\n");        \
+               fflush(stdout);      \
+       } while(0)
+#else
+#define dbg(...) do {} while(0)
+#endif
+
+#define NSEC_PER_SEC 1000000000
+
+#define timespecsub(a, b, result)                                \
+       do {                                                     \
+               (result)->tv_sec = (a)->tv_sec - (b)->tv_sec;    \
+               (result)->tv_nsec = (a)->tv_nsec - (b)->tv_nsec; \
+               if ((result)->tv_nsec < 0) {                     \
+                       --(result)->tv_sec;                      \
+                       (result)->tv_nsec += 1000000000;         \
+               }                                                \
+       } while(0)
+
+struct fps_limit_stats {
+       struct timespec time_start;
+       struct timespec time_end;
+       unsigned int fps;
+};
+
+static void fps_limit_init(struct fps_limit_stats *stats, unsigned int fps)
+{
+       memset(stats, 0, sizeof(*stats));
+
+       clock_gettime(CLOCK_MONOTONIC, &stats->time_start);
+       dbg("Init time: s: %ld, ns: %ld", stats->time_start.tv_sec, stats->time_start.tv_nsec);
+
+       stats->fps = fps;
+}
+
+static void fps_limit_sleep(struct fps_limit_stats *stats)
+{
+       struct timespec elapsed;
+
+       dbg("Start time: s: %ld, ns: %ld", stats->time_start.tv_sec, stats->time_start.tv_nsec);
+
+       clock_gettime(CLOCK_MONOTONIC, &stats->time_end);
+       dbg("End time: s: %ld, ns: %ld", stats->time_end.tv_sec, stats->time_end.tv_nsec);
+
+       timespecsub(&stats->time_end, &stats->time_start, &elapsed);
+       dbg("Elapsed s: %ld ns: %ld", elapsed.tv_sec, elapsed.tv_nsec);
+
+       if (elapsed.tv_sec == 0 && elapsed.tv_nsec < NSEC_PER_SEC / stats->fps) {
+               struct timespec remaining = {0, 0};
+
+               /* remaining delay, _relative_ to time_end */
+               remaining.tv_nsec = (NSEC_PER_SEC / stats->fps) - elapsed.tv_nsec;
+               dbg("Sleeping for: ns: %ld", remaining.tv_nsec);
+
+               clock_nanosleep(CLOCK_MONOTONIC, 0, &remaining, NULL);
+       }
+
+       /* update the stats for the next iteration */
+       clock_gettime(CLOCK_MONOTONIC, &stats->time_start);
+}
+#endif /* FPS_LIMIT_H */