From 5edeec1b20fcb5900d4f1408594d1e76b6c544f0 Mon Sep 17 00:00:00 2001 From: FRIGN Date: Mon, 23 Jun 2014 16:51:51 +0200 Subject: [PATCH] Use monotonic clock to prevent timing issues This patch replaces the gettimeofday()/timeval-system with uses of clock_gettime() with a monolithic clock and timespec-structs. gettimeofday() is not accurate and prone to jumps and POSIX.1-2008 marks it as obsolete. Read more here [0]. The patch should speak for itself and decreases the binary size for me by almost 200K(!). [0]: http://blog.habets.pp.se/2010/09/gettimeofday-should-never-be-used-to-measure-time Signed-off-by: Roberto E. Vargas Caballero --- st.c | 27 +++++++++++++-------------- 1 file changed, 13 insertions(+), 14 deletions(-) diff --git a/st.c b/st.c index 26053b0..17142a4 100644 --- a/st.c +++ b/st.c @@ -76,7 +76,7 @@ char *argv0; #define LIMIT(x, a, b) (x) = (x) < (a) ? (a) : (x) > (b) ? (b) : (x) #define ATTRCMP(a, b) ((a).mode != (b).mode || (a).fg != (b).fg || (a).bg != (b).bg) #define IS_SET(flag) ((term.mode & (flag)) != 0) -#define TIMEDIFF(t1, t2) ((t1.tv_sec-t2.tv_sec)*1000 + (t1.tv_usec-t2.tv_usec)/1000) +#define TIMEDIFF(t1, t2) ((t1.tv_sec-t2.tv_sec)*1000 + (t1.tv_nsec-t2.tv_nsec)/10E6) #define CEIL(x) (((x) != (int) (x)) ? (x) + 1 : (x)) #define MODBIT(x, set, bit) ((set) ? ((x) |= (bit)) : ((x) &= ~(bit))) @@ -294,8 +294,8 @@ typedef struct { char *clip; Atom xtarget; bool alt; - struct timeval tclick1; - struct timeval tclick2; + struct timespec tclick1; + struct timespec tclick2; } Selection; typedef union { @@ -860,7 +860,7 @@ mousereport(XEvent *e) { void bpress(XEvent *e) { - struct timeval now; + struct timespec now; Mousekey *mk; if(IS_SET(MODE_MOUSE) && !(e->xbutton.state & forceselmod)) { @@ -877,7 +877,7 @@ bpress(XEvent *e) { } if(e->xbutton.button == Button1) { - gettimeofday(&now, NULL); + clock_gettime(CLOCK_MONOTONIC, &now); /* Clear previous selection, logically and visually. */ selclear(NULL); @@ -3709,7 +3709,8 @@ run(void) { int w = xw.w, h = xw.h; fd_set rfd; int xfd = XConnectionNumber(xw.dpy), xev, blinkset = 0, dodraw = 0; - struct timeval drawtimeout, *tv = NULL, now, last, lastblink; + struct timespec drawtimeout, *tv = NULL, now, last, lastblink; + long deltatime; /* Waiting for window mapping */ while(1) { @@ -3725,17 +3726,15 @@ run(void) { ttynew(); cresize(w, h); - gettimeofday(&last, NULL); + clock_gettime(CLOCK_MONOTONIC, &last); lastblink = last; for(xev = actionfps;;) { - long deltatime; - FD_ZERO(&rfd); FD_SET(cmdfd, &rfd); FD_SET(xfd, &rfd); - if(select(MAX(xfd, cmdfd)+1, &rfd, NULL, NULL, tv) < 0) { + if(pselect(MAX(xfd, cmdfd)+1, &rfd, NULL, NULL, tv, NULL) < 0) { if(errno == EINTR) continue; die("select failed: %s\n", strerror(errno)); @@ -3752,9 +3751,9 @@ run(void) { if(FD_ISSET(xfd, &rfd)) xev = actionfps; - gettimeofday(&now, NULL); + clock_gettime(CLOCK_MONOTONIC, &now); drawtimeout.tv_sec = 0; - drawtimeout.tv_usec = (1000/xfps) * 1000; + drawtimeout.tv_nsec = (1000/xfps) * 10E6; tv = &drawtimeout; dodraw = 0; @@ -3789,9 +3788,9 @@ run(void) { if(blinkset) { if(TIMEDIFF(now, lastblink) \ > blinktimeout) { - drawtimeout.tv_usec = 1; + drawtimeout.tv_nsec = 1000; } else { - drawtimeout.tv_usec = (1000 * \ + drawtimeout.tv_nsec = (10E6 * \ (blinktimeout - \ TIMEDIFF(now, lastblink)));