diff options
| -rw-r--r-- | gpsd.c | 49 | ||||
| -rw-r--r-- | gpsd.h-tail | 2 | ||||
| -rw-r--r-- | serial.c | 2 |
3 files changed, 45 insertions, 8 deletions
@@ -106,7 +106,7 @@ * when throttled_write() fills up the outbound buffers and the * NOREAD_TIMEOUT expires. * - * Finally, RELEASE_TIMEOUT sets the amount of time we hold a device + * RELEASE_TIMEOUT sets the amount of time we hold a device * open after the last subscriber closes it; this is nonzero so a * client that does open/query/close will have time to come back and * do another single-shot query, if it wants to, before the device is @@ -117,10 +117,14 @@ * device is in progress. The result is that if you close the device * when it's powered up, a re-open can fail with EIO and needs to be * tried repeatedly. Better to avoid this... + * + * DEVICE_REAWAKE says how long to wait before repolling after a zero-length + * read. It's there so we avoid spinning forever on an EOF condition. */ #define COMMAND_TIMEOUT 60*15 #define NOREAD_TIMEOUT 60*3 #define RELEASE_TIMEOUT 60 +#define DEVICE_REAWAKE 0.01 #define QLEN 5 @@ -1358,13 +1362,27 @@ static void consume_packets(struct gps_device_t *device) } else if (changed == NODATA_IS) { /* * No data on the first fragment read means the device - * fd was in an end-of-file condition on select. + * fd may have been in an end-of-file condition on select. */ if (fragments == 0) { - gpsd_report(LOG_WARN, + gpsd_report(LOG_DATA, "%s returned zero bytes\n", device->gpsdata.dev.path); - deactivate_device(device); + if (device->zerokill) + /* failed timeout-and-reawake, kill it */ + deactivate_device(device); + else { + /* + * Disable listening to this fd for long enough + * that the buffer can fill up again. + */ + gpsd_report(LOG_DATA, + "%s will be repolled in %f seconds\n", + device->gpsdata.dev.path, DEVICE_REAWAKE); + device->reawake = timestamp() + DEVICE_REAWAKE; + FD_CLR(device->gpsdata.gps_fd, &all_fds); + adjust_max_fd(device->gpsdata.gps_fd, false); + } } /* * No data on later fragment reads just means the @@ -1375,6 +1393,10 @@ static void consume_packets(struct gps_device_t *device) break; } + /* we got actual data, head off the reawake special case */ + device->zerokill = false; + device->reawake = 0; + /* must have a full packet to continue */ if ((changed & PACKET_IS) == 0) break; @@ -1895,10 +1917,21 @@ int main(int argc, char *argv[]) if (device->device_type != NULL) rtcm_relay(device); - /* get data from the device */ - if (device->gpsdata.gps_fd >= 0 - && FD_ISSET(device->gpsdata.gps_fd, &rfds)) - consume_packets(device); + if (device->gpsdata.gps_fd >= 0) { + if (FD_ISSET(device->gpsdata.gps_fd, &rfds)) + /* get data from the device */ + consume_packets(device); + else if (device->reawake>0 && timestamp()>device->reawake) { + /* device may have had a zero-length read */ + gpsd_report(LOG_DATA, + "%s reawakened after zero-length read\n", + device->gpsdata.dev.path); + device->reawake = 0; + device->zerokill = true; + FD_SET(device->gpsdata.gps_fd, &all_fds); + adjust_max_fd(device->gpsdata.gps_fd, true); + } + } } /* devices */ #ifdef NOT_FIXED diff --git a/gpsd.h-tail b/gpsd.h-tail index 65ed92ad..fd5cbc0c 100644 --- a/gpsd.h-tail +++ b/gpsd.h-tail @@ -309,6 +309,8 @@ struct gps_device_t { char subtype[64]; /* firmware version or subtype ID */ double opentime; double releasetime; + bool zerokill; + double reawake; #ifdef NTPSHM_ENABLE int shmindex; double last_fixtime; /* so updates happen once */ @@ -72,6 +72,8 @@ void gpsd_tty_init(struct gps_device_t *session) session->shmTimeP = -1; # endif /* PPS_ENABLE */ #endif /* NTPSHM_ENABLE */ + session->zerokill = false; + session->reawake = 0; } #if defined(__CYGWIN__) |