diff options
| -rw-r--r-- | gpsd.c | 35 | ||||
| -rwxr-xr-x | gpsd.hotplug | 6 | ||||
| -rw-r--r-- | gpsd.xml | 80 |
3 files changed, 91 insertions, 30 deletions
@@ -406,11 +406,11 @@ static int handle_request(int cfd, char *buf, int buflen) if (*p == '=') { p = getline(++p, &stash); gpsd_report(1,"<= client(%d): switching to %s\n",cfd,stash); - if ((chp = find_device(stash)) - || (chp = open_device(stash, 1))) { + if ((chp = find_device(stash))) { whoami->tied = 1; device = chp->device; } + free(stash); } snprintf(phrase, sizeof(phrase), ",F=%s", device->gpsd_device); break; @@ -418,12 +418,6 @@ static int handle_request(int cfd, char *buf, int buflen) snprintf(phrase, sizeof(phrase), ",I=%s", device->device_type->typename); break; case 'K': - if (*p == '=') { - p = getline(++p, &stash); - gpsd_report(1,"<= client(%d): kill-marking %s\n", cfd, stash); - if ((chp = find_device(stash))) - chp->state = CHANNEL_KILLED; - } strcpy(phrase, ",K="); for (i = 0; i < MAXDEVICES; i++) if (channels[i].device && strlen(phrase)+strlen(device->gpsd_device)+1 < sizeof(phrase)) { @@ -662,6 +656,30 @@ static int handle_request(int cfd, char *buf, int buflen) return throttled_write(cfd, reply, strlen(reply)); } +static void handle_control(int sfd, char *buf) +/* handle privileged commands coming through the control socket */ +{ + char *p, *stash; + struct channel_t *chp; + + if (buf[0] == '-') { + p = getline(buf+1, &stash); + gpsd_report(1,"<= control(%d): removing %s\n", sfd, stash); + if ((chp = find_device(stash))) + chp->state = CHANNEL_KILLED; + free(stash); + } else if (buf[0] == '+') { + p = getline(buf+1, &stash); + if (!find_device(stash)) + gpsd_report(1,"<= control(%d): %s already active \n", sfd, stash); + else { + gpsd_report(1,"<= control(%d): adding %s \n", sfd, stash); + open_device(stash, 1); + } + free(stash); + } +} + int main(int argc, char *argv[]) { static char *pid_file = NULL; @@ -858,6 +876,7 @@ int main(int argc, char *argv[]) if (read(cfd, buf, sizeof(buf)-1) > 0) { gpsd_report(1, "<= (control %d): %s\n", cfd, buf); + handle_control(cfd, buf); } } diff --git a/gpsd.hotplug b/gpsd.hotplug index b4454a25..0382d7ef 100755 --- a/gpsd.hotplug +++ b/gpsd.hotplug @@ -45,10 +45,10 @@ def wake_up_gpsd(devpath): if not connect: return - # We've got a live connection to gpsd. Ship it the right F command. - # No need to look at the response; gpsd will lock on to the device + # We've got a live connection to the gpsd control socket. + # No response, because gpsd will lock on to the device # if it's really a GPS and ignore it if it's not. - connect.write("F=%s\r\n" % tty) + connect.write("+%s\r\n" % tty) connect.close() return @@ -1,7 +1,9 @@ <?xml version="1.0" encoding="ISO-8859-1"?> <!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.1.2//EN" - "docbook/docbookx.dtd"> + "docbook/docbookx.dtd" [ +<!ENTITY gpsdsock "/var/run/gpsd.sock"> +]> <refentry id='gpsd.8'> <refmeta> <refentrytitle>gpsd</refentrytitle> @@ -119,16 +121,23 @@ to standard error.</para> </variablelist> <para>At any given time, each client will be listening to only one of -the GPSes devices known to the daemon. By default, a client's device -is the one most recently on-line at the time the client connects. A -client may use the 'F' command to specify a device to listen to.</para> - -<para>The request protocol for gpsd clients is very simple. Each -request normally consists of a single ASCII character followed by a newline. -Case of the request character is ignored, Each request returns a line -of response text ended by a CR/LF. Requests and responses are as -follows, with %f standing for a decimal float numeral and %d for -decimal integer numeral:</para> +the GPSes known to the daemon. By default, a client's device is the +one most recently on-line at the time the client connects. A client +may use the 'F' command to specify a device to listen to.</para> + +<para>The 'F' command fails if the specified device name is not on the +daemon's internal search list. This search list is initialized with +<filename>/dev/gps</filename> or the path given in the -f command-line +option if that was specified. For security reasons, ordinary clients +cannot change this search list; instead, this must be done via the +daemon's local control socket.</para> + +<para>The request protocol for <application>gpsd</application> clients +is very simple. Each request normally consists of a single ASCII +character followed by a newline. Case of the request character is +ignored, Each request returns a line of response text ended by a +CR/LF. Requests and responses are as follows, with %f standing for a +decimal float numeral and %d for decimal integer numeral:</para> <variablelist> <varlistentry> @@ -182,11 +191,12 @@ See also the 'q' command.</para> command 'f' requests a response containing 'f=' followed by the name of the active GPS device. The command may be followed by an '=', in which case all following printable characters up to but not including -the next CR/LF are interpreted as the name of a trial GPS device. The -trial device is opened and read to see if a GPS can be found there. -If it can, the trial device becomes the active device for this client. -The response to this form of the command is to list the name of the -active device.</para> +the next CR/LF are interpreted as the name of a trial GPS device. If +the trial device is in <application>gpsd</application>'s device list, +it is opened and read to see if a GPS can be found there. If it can, +the trial device becomes the active device for this client. The +response to this form of the command is to list the name of the active +device.</para> <para>(At protocol level 1, the F command failed if more than one client was attached, and multiple devices were not supported.)</para> @@ -209,8 +219,7 @@ successfully recognized as GPSes). Note that the fact that a devicename appears in this list does not guarantee that a GPS is connected to it and active.</para> -<para>(At protocol level 1, there was no K command. Note that this -command is experimental and its semantics may change.)</para> +<para>(At protocol level 1, there was no K command.)</para> </listitem> </varlistentry> @@ -457,9 +466,24 @@ string "GPSD" followed by the replies. Examples:</para> device once per second. Thus, it can be left running in background and survive having a GPS repeatedly unplugged and plugged back in. When it is properly installed along with hotplug notifier -scripts feeding it F commands, <application>gpsd</application> +scripts feeding it device-add commands, <application>gpsd</application> should require no configuration or user action to find devices.</para> +<para>The commands to add and remove GPS device paths from the +daemon's internal search list cannot be sent over the socket from a +client. Instead, they must be written to a local Unix-domain socket +which will be accessible only to programs running as root. This +control socket will be located at <filename>&gpsdsock;</filename>.</para> + +<para>To point <application>gpsd</application> at a device that may be +a GPS, write to the control socket a plus sign ('+') followed by the +device name followed by LF or CR-LF. Thus, to point the daemon at +<filename>/dev/foo</filename>. send "+/dev/foo\n". To tell the daemon +that a device has been disconnected and is no longer available, send a +minus sign ('-') followed by the device name followed by LF or +CR-LF. Thus, to remove <filename>/dev/foo</filename> from the search +list. send "-/dev/foo\n".</para> + <para>The recommended mode for clients is watcher mode. In watcher mode <application>gpsd</application> ships a line of data to the client each time the GPS gets either a fix update or a satellite @@ -591,6 +615,24 @@ from one device's GGA with latitude/longitude from another's RMC/GLL after the second sentence has arrived.</para> </refsect1> +<refsect1 id='files'><title>FILES</title> + +<variablelist> +<varlistentry> +<term><filename>/dev/gps</filename></term> +<listitem> +<para>Default path to a GPS device.</para> +</listitem> +</varlistentry> +<varlistentry> +<term><filename>&gpsdsock;</filename></term> +<listitem> +<para>Location of the control socket for device add/remove commands.</para> +</listitem> +</varlistentry> +</variablelist> + +</refsect1> <refsect1 id='standards'><title>APPLICABLE STANDARDS</title> <para>The official NMEA protocol standard is available on paper from |