diff options
| -rw-r--r-- | .gitignore | 1 | ||||
| -rw-r--r-- | Makefile | 7 | ||||
| -rw-r--r-- | reserve-monitor-test.c | 102 | ||||
| -rw-r--r-- | reserve-monitor.c | 259 | ||||
| -rw-r--r-- | reserve-monitor.h | 62 |
5 files changed, 430 insertions, 1 deletions
@@ -1,2 +1,3 @@ *.o reserve-test +reserve-monitor-test @@ -23,8 +23,13 @@ CFLAGS=-Wall -Wextra -O0 -g -pipe `pkg-config --cflags dbus-1` LIBS=`pkg-config --libs dbus-1` +all: reserve-test reserve-monitor-test + reserve-test: reserve.h reserve.o reserve-test.o $(CC) $(CFLAGS) $^ -o $@ $(LIBS) +reserve-monitor-test: reserve-monitor.h reserve-monitor.o reserve-monitor-test.o + $(CC) $(CFLAGS) $^ -o $@ $(LIBS) + clean: - rm -f *.o reserve-test + rm -f *.o reserve-test reserve-monitor-test diff --git a/reserve-monitor-test.c b/reserve-monitor-test.c new file mode 100644 index 0000000..aa9fdb1 --- /dev/null +++ b/reserve-monitor-test.c @@ -0,0 +1,102 @@ +/*** + Copyright 2009 Lennart Poettering + + Permission is hereby granted, free of charge, to any person + obtaining a copy of this software and associated documentation files + (the "Software"), to deal in the Software without restriction, + including without limitation the rights to use, copy, modify, merge, + publish, distribute, sublicense, and/or sell copies of the Software, + and to permit persons to whom the Software is furnished to do so, + subject to the following conditions: + + The above copyright notice and this permission notice shall be + included in all copies or substantial portions of the Software. + + THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS + BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN + ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + SOFTWARE. +***/ + +#include <stdio.h> +#include <string.h> +#include <stdlib.h> +#include <unistd.h> +#include <time.h> +#include <dbus/dbus.h> + +#include "reserve-monitor.h" + +static DBusConnection *connection = NULL; + +static void change_cb(rm_monitor *m) { + int e; + + if ((e = rm_busy(m)) < 0) { + fprintf(stderr, "Failed to query device status: %s\n", strerror(-e)); + dbus_connection_close(connection); + return; + } + + printf("Device is busy: %s\n", e ? "yes" : "no"); +} + +int main(int argc, char *argv[]) { + DBusError error; + int r = 1, e; + rm_monitor *monitor = NULL; + const char *dname = NULL; + + dbus_error_init(&error); + + if (argc >= 2) + dname = argv[1]; + else + dname = "Audio0"; + + if (!(connection = dbus_bus_get_private(DBUS_BUS_SESSION, &error))) { + fprintf(stderr, "Failed to connect to session bus: %s\n", error.message); + goto finish; + } + + if ((e = rm_watch( + &monitor, + connection, + dname, + change_cb, + &error)) < 0) { + + fprintf(stderr, "Failed to watch device: %s\n", strerror(-e)); + goto finish; + } + + if ((e = rm_busy(monitor)) < 0) { + fprintf(stderr, "Failed to query device status: %s\n", strerror(-e)); + goto finish; + } + + printf("Device is busy: %s\n", e ? "yes" : "no"); + + while (dbus_connection_read_write_dispatch(connection, -1)) + ; + + r = 0; + fprintf(stderr, "Exiting cleanly.\n"); + +finish: + if (monitor) + rm_release(monitor); + + if (connection) { + if (dbus_connection_get_is_connected(connection)) + dbus_connection_close(connection); + + dbus_connection_unref(connection); + } + + return r; +} diff --git a/reserve-monitor.c b/reserve-monitor.c new file mode 100644 index 0000000..64d2a7c --- /dev/null +++ b/reserve-monitor.c @@ -0,0 +1,259 @@ +/*** + Copyright 2009 Lennart Poettering + + Permission is hereby granted, free of charge, to any person + obtaining a copy of this software and associated documentation files + (the "Software"), to deal in the Software without restriction, + including without limitation the rights to use, copy, modify, merge, + publish, distribute, sublicense, and/or sell copies of the Software, + and to permit persons to whom the Software is furnished to do so, + subject to the following conditions: + + The above copyright notice and this permission notice shall be + included in all copies or substantial portions of the Software. + + THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS + BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN + ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + SOFTWARE. +***/ + +#include <string.h> +#include <unistd.h> +#include <errno.h> +#include <stdlib.h> +#include <stdio.h> +#include <assert.h> + +#include "reserve-monitor.h" + +struct rm_monitor { + int ref; + + char *device_name; + char *service_name; + + DBusConnection *connection; + + unsigned busy:1; + unsigned filtering:1; + unsigned matching:1; + + rm_change_cb_t change_cb; + void *userdata; +}; + +#define SERVICE_PREFIX "org.freedesktop.ReserveDevice1." + +static DBusHandlerResult filter_handler( + DBusConnection *c, + DBusMessage *s, + void *userdata) { + + DBusMessage *reply; + rm_monitor *m; + DBusError error; + + dbus_error_init(&error); + + m = userdata; + assert(m->ref >= 1); + + if (dbus_message_is_signal(s, "org.freedesktop.DBus", "NameOwnerChanged")) { + const char *name, *old, *new; + + if (!dbus_message_get_args( + s, + &error, + DBUS_TYPE_STRING, &name, + DBUS_TYPE_STRING, &old, + DBUS_TYPE_STRING, &new, + DBUS_TYPE_INVALID)) + goto invalid; + + if (strcmp(name, m->service_name) == 0) { + + m->busy = !!(new && *new); + + if (m->change_cb) { + m->ref++; + m->change_cb(m); + rm_release(m); + } + } + } + + return DBUS_HANDLER_RESULT_NOT_YET_HANDLED; + +invalid: + if (!(reply = dbus_message_new_error( + s, + DBUS_ERROR_INVALID_ARGS, + "Invalid arguments"))) + goto oom; + + if (!dbus_connection_send(c, reply, NULL)) + goto oom; + + dbus_message_unref(reply); + + dbus_error_free(&error); + + return DBUS_HANDLER_RESULT_HANDLED; + +oom: + if (reply) + dbus_message_unref(reply); + + dbus_error_free(&error); + + return DBUS_HANDLER_RESULT_NEED_MEMORY; +} + +int rm_watch( + rm_monitor **_m, + DBusConnection *connection, + const char*device_name, + rm_change_cb_t change_cb, + DBusError *error) { + + rm_monitor *m = NULL; + int r; + DBusError _error; + + if (!error) + error = &_error; + + dbus_error_init(error); + + if (!_m) + return -EINVAL; + + if (!connection) + return -EINVAL; + + if (!device_name) + return -EINVAL; + + if (!(m = calloc(sizeof(rm_monitor), 1))) + return -ENOMEM; + + m->ref = 1; + + if (!(m->device_name = strdup(device_name))) { + r = -ENOMEM; + goto fail; + } + + m->connection = dbus_connection_ref(connection); + m->change_cb = change_cb; + + if (!(m->service_name = malloc(sizeof(SERVICE_PREFIX) + strlen(device_name)))) { + r = -ENOMEM; + goto fail; + } + sprintf(m->service_name, SERVICE_PREFIX "%s", m->device_name); + + if (!(dbus_connection_add_filter(m->connection, filter_handler, m, NULL))) { + r = -ENOMEM; + goto fail; + } + + m->filtering = 1; + + dbus_bus_add_match(m->connection, + "type='signal'," + "sender='" DBUS_SERVICE_DBUS "'," + "interface='" DBUS_INTERFACE_DBUS "'," + "member='NameOwnerChanged'", error); + + if (dbus_error_is_set(error)) { + r = -EIO; + goto fail; + } + + m->matching = 1; + + m->busy = dbus_bus_name_has_owner(m->connection, m->service_name, error); + + if (dbus_error_is_set(error)) { + r = -EIO; + goto fail; + } + + *_m = m; + return 0; + +fail: + if (&_error == error) + dbus_error_free(&_error); + + if (m) + rm_release(m); + + return r; +} + +void rm_release(rm_monitor *m) { + if (!m) + return; + + assert(m->ref > 0); + + if (--m->ref > 0) + return; + + if (m->matching) + dbus_bus_remove_match( + m->connection, + "type='signal'," + "sender='" DBUS_SERVICE_DBUS "'," + "interface='" DBUS_INTERFACE_DBUS "'," + "member='NameOwnerChanged'", NULL); + + if (m->filtering) + dbus_connection_remove_filter( + m->connection, + filter_handler, + m); + + free(m->device_name); + free(m->service_name); + + if (m->connection) + dbus_connection_unref(m->connection); + + free(m); +} + +int rm_busy(rm_monitor *m) { + if (!m) + return -EINVAL; + + assert(m->ref > 0); + + return m->busy; +} + +void rm_set_userdata(rm_monitor *m, void *userdata) { + + if (!m) + return; + + assert(m->ref > 0); + m->userdata = userdata; +} + +void* rm_get_userdata(rm_monitor *m) { + + if (!m) + return NULL; + + assert(m->ref > 0); + + return m->userdata; +} diff --git a/reserve-monitor.h b/reserve-monitor.h new file mode 100644 index 0000000..4f4a833 --- /dev/null +++ b/reserve-monitor.h @@ -0,0 +1,62 @@ +#ifndef fooreservemonitorhfoo +#define fooreservemonitorhfoo + +/*** + Copyright 2009 Lennart Poettering + + Permission is hereby granted, free of charge, to any person + obtaining a copy of this software and associated documentation files + (the "Software"), to deal in the Software without restriction, + including without limitation the rights to use, copy, modify, merge, + publish, distribute, sublicense, and/or sell copies of the Software, + and to permit persons to whom the Software is furnished to do so, + subject to the following conditions: + + The above copyright notice and this permission notice shall be + included in all copies or substantial portions of the Software. + + THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS + BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN + ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + SOFTWARE. +***/ + +#include <dbus/dbus.h> +#include <inttypes.h> + +typedef struct rm_monitor rm_monitor; + +/* Prototype for a function that is called whenever the reservation + * device of a device changes. Use rm_monitor_busy() to find out the + * new state.*/ +typedef void (*rm_change_cb_t)(rm_monitor *m); + +/* Creates a monitor for watching the lock status of a device. Returns + * 0 on success, a negative errno style return value on error. The + * DBus error might be set as well if the error was caused D-Bus. */ +int rm_watch( + rm_monitor **m, /* On success a pointer to the newly allocated rm_device object will be filled in here */ + DBusConnection *connection, /* Session bus (when D-Bus learns about user busses we should switchg to user busses) */ + const char *device_name, /* The device to monitor, e.g. "Audio0" */ + rm_change_cb_t change_cb, /* Will be called whenever the lock status changes. May be NULL */ + DBusError *error); /* If we fail due to a D-Bus related issue the error will be filled in here. May be NULL. */ + +/* Free a rm_monitor object */ +void rm_release(rm_monitor *m); + +/* Checks whether the device is currently reserved, and returns 1 + * then, 0 if not, negative errno style error code value on error. */ +int rm_busy(rm_monitor *m); + +/* Attach a userdata pointer to an rm_monitor */ +void rm_set_userdata(rm_monitor *m, void *userdata); + +/* Query the userdata pointer from an rm_monitor. Returns NULL if no + * userdata was set. */ +void* rm_get_userdata(rm_monitor *m); + +#endif |