diff options
| author | Arthur de Jong <arthur@arthurdejong.org> | 2013-01-18 14:41:29 +0100 |
|---|---|---|
| committer | Arthur de Jong <arthur@arthurdejong.org> | 2013-01-18 14:41:29 +0100 |
| commit | 16db5968cd6898bbcb586e33b2ea5bd40ce31cdc (patch) | |
| tree | ba53ba779d22833b9f4f396a141066b1e6c4dde4 /common | |
| parent | b01cd224e2880b17e91c01c1697ee267a7d7fd2a (diff) | |
restructure timeout calculation in tio to reduce the number of times gettimeofday() is called
git-svn-id: http://arthurdejong.org/svn/nss-pam-ldapd/nss-pam-ldapd@1923 ef36b2f9-881f-0410-afb5-c4e39611909c
Diffstat (limited to 'common')
| -rw-r--r-- | common/tio.c | 71 |
1 files changed, 30 insertions, 41 deletions
diff --git a/common/tio.c b/common/tio.c index f4a769a..9383733 100644 --- a/common/tio.c +++ b/common/tio.c @@ -2,7 +2,7 @@ tio.c - timed io functions This file is part of the nss-pam-ldapd library. - Copyright (C) 2007, 2008, 2010, 2011, 2012 Arthur de Jong + Copyright (C) 2007, 2008, 2010, 2011, 2012, 2013 Arthur de Jong This library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public @@ -75,31 +75,24 @@ struct tio_fileinfo { #endif /* DEBUG_TIO_STATS */ }; -/* build a timeval for comparison to when the operation should be finished */ -static inline void tio_get_deadline(struct timeval *deadline, int timeout) -{ - if (gettimeofday(deadline, NULL)) - { - /* just blank it in case of errors */ - deadline->tv_sec = 0; - deadline->tv_usec = 0; - return; - } - deadline->tv_sec += timeout / 1000; - deadline->tv_usec += (timeout % 1000) * 1000; -} - /* update the timeout to the value that is remaining before deadline returns non-zero if there is no more time before the deadline */ -static inline int tio_time_remaining(const struct timeval *deadline) +static inline int tio_time_remaining(struct timeval *deadline, int timeout) { struct timeval tv; - /* get the current time */ - if (gettimeofday(&tv, NULL)) + /* if this is the first call, set the deadline and return the full time */ + if ((deadline->tv_sec == 0) && (deadline->tv_usec == 0)) { - /* 1 second default if gettimeofday() is broken */ - return 1000; + if (gettimeofday(deadline, NULL) == 0) + { + deadline->tv_sec += timeout / 1000; + deadline->tv_usec += (timeout % 1000) * 1000; + } + return timeout; } + /* get the current time (fall back to full time on error) */ + if (gettimeofday(&tv, NULL)) + return timeout; /* calculate time remaining in miliseconds */ return (deadline->tv_sec - tv.tv_sec) * 1000 + (deadline->tv_usec - tv.tv_usec) / 1000; @@ -151,36 +144,36 @@ TFILE *tio_fdopen(int fd, int readtimeout, int writetimeout, /* wait for any activity on the specified file descriptor using the specified deadline */ -static int tio_wait(TFILE *fp, int readfd, const struct timeval *deadline) +static int tio_wait(TFILE *fp, int readfd, struct timeval *deadline) { - int timeout; + int timeout, max_timeout; struct pollfd fds[1]; int rv; while (1) { - /* figure out the time we need to wait */ - if ((timeout = tio_time_remaining(deadline)) < 0) - { - errno = ETIME; - return -1; - } - /* wait for activity */ + /* figure out which values to use */ if (readfd) { fds[0].fd = fp->fd; fds[0].events = POLLIN; - /* santiy check for moving clock */ - if (timeout > fp->readtimeout) - timeout = fp->readtimeout; + max_timeout = fp->readtimeout; } else { fds[0].fd = fp->fd; fds[0].events = POLLOUT; - /* santiy check for moving clock */ - if (timeout > fp->writetimeout) - timeout = fp->writetimeout; + max_timeout = fp->writetimeout; + } + /* figure out the time we need to wait */ + if ((timeout = tio_time_remaining(deadline, max_timeout)) < 0) + { + errno = ETIME; + return -1; } + /* sanitiy check for moving clock */ + if (timeout > max_timeout) + timeout = max_timeout; + /* wait for activity */ rv = poll(fds, 1, timeout); if (rv > 0) return 0; /* we have activity */ @@ -201,15 +194,13 @@ static int tio_wait(TFILE *fp, int readfd, const struct timeval *deadline) if no data was read in the specified time an error is returned */ int tio_read(TFILE *fp, void *buf, size_t count) { - struct timeval deadline; + struct timeval deadline = {0, 0}; int rv; uint8_t *tmp; size_t newsz; size_t len; /* have a more convenient storage type for the buffer */ uint8_t *ptr = (uint8_t *)buf; - /* build a time by which we should be finished */ - tio_get_deadline(&deadline, fp->readtimeout); /* loop until we have returned all the needed data */ while (1) { @@ -398,9 +389,7 @@ static int tio_writebuf(TFILE *fp) /* write all the data in the buffer to the stream */ int tio_flush(TFILE *fp) { - struct timeval deadline; - /* build a time by which we should be finished */ - tio_get_deadline(&deadline, fp->writetimeout); + struct timeval deadline = {0, 0}; /* loop until we have written our buffer */ while (fp->writebuffer.len > 0) { |