From 5d301b8aecc286d6ec7e92b0864d66360ea57205 Mon Sep 17 00:00:00 2001

From: David Herrmann <dh.herrmann@gmail.com>

Date: Mon, 22 Sep 2014 17:34:13 +0200

Subject: [PATCH] terminal: make evdev logind-matches per session

Instead of adding matches per device, we now add logind matches per

session. This reduces the number of matches considerably and saves

resources.

---

 src/libsystemd-terminal/idev-evdev.c    | 170 ++++++++------------------------

 src/libsystemd-terminal/idev-internal.h |   4 +

 src/libsystemd-terminal/idev.c          | 114 +++++++++++++++++++++

 3 files changed, 158 insertions(+), 130 deletions(-)

diff --git a/src/libsystemd-terminal/idev-evdev.c b/src/libsystemd-terminal/idev-evdev.c

index 719e18c316..63fa89e47d 100644

--- a/src/libsystemd-terminal/idev-evdev.c

+++ b/src/libsystemd-terminal/idev-evdev.c

@@ -60,9 +60,6 @@ struct unmanaged_evdev {

 struct managed_evdev {

         idev_evdev evdev;

         dev_t devnum;

-

-        sd_bus_slot *slot_pause_device;

-        sd_bus_slot *slot_resume_device;

         sd_bus_slot *slot_take_device;

         bool requested : 1;             /* TakeDevice() was sent */

@@ -580,7 +577,7 @@ static int managed_evdev_take_device_fn(sd_bus *bus,

         return 0;

 }

-static void managed_evdev_resume(idev_element *e) {

+static void managed_evdev_enable(idev_element *e) {

         _cleanup_bus_message_unref_ sd_bus_message *m = NULL;

         managed_evdev *em = managed_evdev_from_element(e);

         idev_session *s = e->session;

@@ -628,7 +625,7 @@ error:

                   s->name, e->name, strerror(-r));

 }

-static void managed_evdev_pause(idev_element *e) {

+static void managed_evdev_disable(idev_element *e) {

         _cleanup_bus_message_unref_ sd_bus_message *m = NULL;

         managed_evdev *em = managed_evdev_from_element(e);

         idev_session *s = e->session;

@@ -686,24 +683,45 @@ static void managed_evdev_pause(idev_element *e) {

                           s->name, e->name, strerror(-r));

 }

-static int managed_evdev_pause_device_fn(sd_bus *bus,

-                                         sd_bus_message *signal,

-                                         void *userdata,

-                                         sd_bus_error *ret_error) {

-        managed_evdev *em = userdata;

-        idev_element *e = &em->evdev.element;

+static void managed_evdev_resume(idev_element *e, int fd) {

+        managed_evdev *em = managed_evdev_from_element(e);

+        idev_session *s = e->session;

+        int r;

+

+        /*

+         * We get ResumeDevice signals whenever logind resumed a previously

+         * paused device. The arguments contain the major/minor number of the

+         * related device and a new file-descriptor for the freshly opened

+         * device-node. We take the file-descriptor and immediately resume the

+         * device.

+         */

+

+        fd = fcntl(fd, F_DUPFD_CLOEXEC, 3);

+        if (fd < 0) {

+                log_debug("idev-evdev: %s/%s: cannot duplicate evdev fd: %m",

+                          s->name, e->name);

+                return;

+        }

+

+        r = idev_evdev_resume(&em->evdev, fd);

+        if (r < 0)

+                log_debug("idev-evdev: %s/%s: cannot resume: %s",

+                          s->name, e->name, strerror(-r));

+

+        return;

+}

+

+static void managed_evdev_pause(idev_element *e, const char *mode) {

+        managed_evdev *em = managed_evdev_from_element(e);

         idev_session *s = e->session;

         idev_context *c = s->context;

-        uint32_t major, minor;

-        const char *mode;

         int r;

         /*

          * We get PauseDevice() signals from logind whenever a device we

          * requested was, or is about to be, paused. Arguments are major/minor

          * number of the device and the mode of the operation.

-         * In case the event is not about our device, we ignore it. Otherwise,

-         * we treat it as asynchronous access-revocation (as if we got HUP on

+         * We treat it as asynchronous access-revocation (as if we got HUP on

          * the device fd). Note that we might have already treated the HUP

          * event via EPOLLHUP, whichever comes first.

          *

@@ -728,17 +746,6 @@ static int managed_evdev_pause_device_fn(sd_bus *bus,

          * acknowledge the request.

          */

-        r = sd_bus_message_read(signal, "uus", &major, &minor, &mode);

-        if (r < 0) {

-                log_debug("idev-evdev: %s/%s: erroneous PauseDevice signal",

-                          s->name, e->name);

-                return 0;

-        }

-

-        /* not our device? */

-        if (makedev(major, minor) != em->devnum)

-                return 0;

-

         idev_evdev_pause(&em->evdev, true);

         if (streq(mode, "pause")) {

@@ -763,7 +770,7 @@ static int managed_evdev_pause_device_fn(sd_bus *bus,

                                                    "org.freedesktop.login1.Session",

                                                    "PauseDeviceComplete");

                 if (r >= 0) {

-                        r = sd_bus_message_append(m, "uu", major, minor);

+                        r = sd_bus_message_append(m, "uu", major(em->devnum), minor(em->devnum));

                         if (r >= 0)

                                 r = sd_bus_send(c->sysbus, m, NULL);

                 }

@@ -772,99 +779,6 @@ static int managed_evdev_pause_device_fn(sd_bus *bus,

                         log_debug("idev-evdev: %s/%s: cannot send PauseDeviceComplete: %s",

                                   s->name, e->name, strerror(-r));

         }

-

-        return 0;

-}

-

-static int managed_evdev_resume_device_fn(sd_bus *bus,

-                                          sd_bus_message *signal,

-                                          void *userdata,

-                                          sd_bus_error *ret_error) {

-        managed_evdev *em = userdata;

-        idev_element *e = &em->evdev.element;

-        idev_session *s = e->session;

-        uint32_t major, minor;

-        int r, fd;

-

-        /*

-         * We get ResumeDevice signals whenever logind resumed a previously

-         * paused device. The arguments contain the major/minor number of the

-         * related device and a new file-descriptor for the freshly opened

-         * device-node.

-         * If the signal is not about our device, we simply ignore it.

-         * Otherwise, we take the file-descriptor and immediately resume the

-         * device.

-         */

-

-        r = sd_bus_message_read(signal, "uuh", &major, &minor, &fd;;

-        if (r < 0) {

-                log_debug("idev-evdev: %s/%s: erroneous ResumeDevice signal",

-                          s->name, e->name);

-                return 0;

-        }

-

-        /* not our device? */

-        if (makedev(major, minor) != em->devnum)

-                return 0;

-

-        fd = fcntl(fd, F_DUPFD_CLOEXEC, 3);

-        if (fd < 0) {

-                log_debug("idev-evdev: %s/%s: cannot duplicate evdev fd: %m",

-                          s->name, e->name);

-                return 0;

-        }

-

-        r = idev_evdev_resume(&em->evdev, fd);

-        if (r < 0)

-                log_debug("idev-evdev: %s/%s: cannot resume: %s",

-                          s->name, e->name, strerror(-r));

-

-        return 0;

-}

-

-static int managed_evdev_setup_bus(managed_evdev *em) {

-        idev_element *e = &em->evdev.element;

-        idev_session *s = e->session;

-        idev_context *c = s->context;

-        _cleanup_free_ char *match = NULL;

-        int r;

-

-        match = strjoin("type='signal',"

-                        "sender='org.freedesktop.login1',"

-                        "interface='org.freedesktop.login1.Session',"

-                        "member='PauseDevice',"

-                        "path='", s->path, "'",

-                        NULL);

-        if (!match)

-                return -ENOMEM;

-

-        r = sd_bus_add_match(c->sysbus,

-                             &em->slot_pause_device,

-                             match,

-                             managed_evdev_pause_device_fn,

-                             em);

-        if (r < 0)

-                return r;

-

-        free(match);

-        match = strjoin("type='signal',"

-                        "sender='org.freedesktop.login1',"

-                        "interface='org.freedesktop.login1.Session',"

-                        "member='ResumeDevice',"

-                        "path='", s->path, "'",

-                        NULL);

-        if (!match)

-                return -ENOMEM;

-

-        r = sd_bus_add_match(c->sysbus,

-                             &em->slot_resume_device,

-                             match,

-                             managed_evdev_resume_device_fn,

-                             em);

-        if (r < 0)

-                return r;

-

-        return 0;

 }

 static int managed_evdev_new(idev_element **out, idev_session *s, struct udev_device *ud) {

@@ -893,10 +807,6 @@ static int managed_evdev_new(idev_element **out, idev_session *s, struct udev_de

         em->evdev = IDEV_EVDEV_INIT(&managed_evdev_vtable, s);

         em->devnum = devnum;

-        r = managed_evdev_setup_bus(em);

-        if (r < 0)

-                return r;

-

         r = idev_element_add(e, name);

         if (r < 0)

                 return r;

@@ -910,18 +820,18 @@ static int managed_evdev_new(idev_element **out, idev_session *s, struct udev_de

 static void managed_evdev_free(idev_element *e) {

         managed_evdev *em = managed_evdev_from_element(e);

-        em->slot_resume_device = sd_bus_slot_unref(em->slot_resume_device);

-        em->slot_pause_device = sd_bus_slot_unref(em->slot_pause_device);

         idev_evdev_destroy(&em->evdev);

         free(em);

 }

 static const idev_element_vtable managed_evdev_vtable = {

         .free                   = managed_evdev_free,

-        .enable                 = managed_evdev_resume,

-        .disable                = managed_evdev_pause,

-        .open                   = managed_evdev_resume,

-        .close                  = managed_evdev_pause,

+        .enable                 = managed_evdev_enable,

+        .disable                = managed_evdev_disable,

+        .open                   = managed_evdev_enable,

+        .close                  = managed_evdev_disable,

+        .resume                 = managed_evdev_resume,

+        .pause                  = managed_evdev_pause,

 };

 /*

diff --git a/src/libsystemd-terminal/idev-internal.h b/src/libsystemd-terminal/idev-internal.h

index c416f4fadd..a159aef211 100644

--- a/src/libsystemd-terminal/idev-internal.h

+++ b/src/libsystemd-terminal/idev-internal.h

@@ -116,6 +116,8 @@ struct idev_element_vtable {

         void (*disable) (idev_element *e);

         void (*open) (idev_element *e);

         void (*close) (idev_element *e);

+        void (*resume) (idev_element *e, int fd);

+        void (*pause) (idev_element *e, const char *mode);

         void (*feedback) (idev_element *e, idev_data *data);

 };

@@ -155,6 +157,8 @@ struct idev_session {

         idev_context *context;

         char *name;

         char *path;

+        sd_bus_slot *slot_resume_device;

+        sd_bus_slot *slot_pause_device;

         Hashmap *element_map;

         Hashmap *device_map;

diff --git a/src/libsystemd-terminal/idev.c b/src/libsystemd-terminal/idev.c

index 8592930662..e979b608b6 100644

--- a/src/libsystemd-terminal/idev.c

+++ b/src/libsystemd-terminal/idev.c

@@ -274,6 +274,22 @@ static void element_disable(idev_element *e) {

         }

 }

+static void element_resume(idev_element *e, int fd) {

+        assert(e);

+        assert(fd >= 0);

+

+        if (e->vtable->resume)

+                e->vtable->resume(e, fd);

+}

+

+static void element_pause(idev_element *e, const char *mode) {

+        assert(e);

+        assert(mode);

+

+        if (e->vtable->pause)

+                e->vtable->pause(e, mode);

+}

+

 /*

  * Sessions

  */

@@ -417,6 +433,98 @@ idev_session *idev_find_session(idev_context *c, const char *name) {

         return hashmap_get(c->session_map, name);

 }

+static int session_resume_device_fn(sd_bus *bus,

+                                    sd_bus_message *signal,

+                                    void *userdata,

+                                    sd_bus_error *ret_error) {

+        idev_session *s = userdata;

+        idev_element *e;

+        uint32_t major, minor;

+        int r, fd;

+

+        r = sd_bus_message_read(signal, "uuh", &major, &minor, &fd;;

+        if (r < 0) {

+                log_debug("idev: %s: erroneous ResumeDevice signal", s->name);

+                return 0;

+        }

+

+        e = idev_find_evdev(s, makedev(major, minor));

+        if (!e)

+                return 0;

+

+        element_resume(e, fd);

+        return 0;

+}

+

+static int session_pause_device_fn(sd_bus *bus,

+                                   sd_bus_message *signal,

+                                   void *userdata,

+                                   sd_bus_error *ret_error) {

+        idev_session *s = userdata;

+        idev_element *e;

+        uint32_t major, minor;

+        const char *mode;

+        int r;

+

+        r = sd_bus_message_read(signal, "uus", &major, &minor, &mode);

+        if (r < 0) {

+                log_debug("idev: %s: erroneous PauseDevice signal", s->name);

+                return 0;

+        }

+

+        e = idev_find_evdev(s, makedev(major, minor));

+        if (!e)

+                return 0;

+

+        element_pause(e, mode);

+        return 0;

+}

+

+static int session_setup_bus(idev_session *s) {

+        _cleanup_free_ char *match = NULL;

+        int r;

+

+        if (!s->managed)

+                return 0;

+

+        match = strjoin("type='signal',"

+                        "sender='org.freedesktop.login1',"

+                        "interface='org.freedesktop.login1.Session',"

+                        "member='ResumeDevice',"

+                        "path='", s->path, "'",

+                        NULL);

+        if (!match)

+                return -ENOMEM;

+

+        r = sd_bus_add_match(s->context->sysbus,

+                             &s->slot_resume_device,

+                             match,

+                             session_resume_device_fn,

+                             s);

+        if (r < 0)

+                return r;

+

+        free(match);

+        match = strjoin("type='signal',"

+                        "sender='org.freedesktop.login1',"

+                        "interface='org.freedesktop.login1.Session',"

+                        "member='PauseDevice',"

+                        "path='", s->path, "'",

+                        NULL);

+        if (!match)

+                return -ENOMEM;

+

+        r = sd_bus_add_match(s->context->sysbus,

+                             &s->slot_pause_device,

+                             match,

+                             session_pause_device_fn,

+                             s);

+        if (r < 0)

+                return r;

+

+        return 0;

+}

+

 int idev_session_new(idev_session **out,

                      idev_context *c,

                      unsigned int flags,

@@ -462,6 +570,10 @@ int idev_session_new(idev_session **out,

         if (!s->device_map)

                 return -ENOMEM;

+        r = session_setup_bus(s);

+        if (r < 0)

+                return r;

+

         r = hashmap_put(c->session_map, s->name, s);

         if (r < 0)

                 return r;

@@ -485,6 +597,8 @@ idev_session *idev_session_free(idev_session *s) {

         if (s->name)

                 hashmap_remove_value(s->context->session_map, s->name, s);

+        s->slot_pause_device = sd_bus_slot_unref(s->slot_pause_device);

+        s->slot_resume_device = sd_bus_slot_unref(s->slot_resume_device);

         s->context = idev_context_unref(s->context);

         hashmap_free(s->device_map);

         hashmap_free(s->element_map);