[systemd-devel] [PATCH] logind: fix build for ARM with sizeof(dev_t) > sizeof(void*)

[David Herrmann]

Unfortunately on ARM-32 systems dev_t can be 64bit and thus we cannot
store it easily in void* keys for hashtables. Fix that by passing a
pointer to the dev_t variable instead.
---
 src/login/logind-session-dbus.c   | 12 +++++++-----
 src/login/logind-session-device.c |  8 +++-----
 src/login/logind-session.c        | 17 ++++++++++++++++-
 3 files changed, 26 insertions(+), 11 deletions(-)

diff --git a/src/login/logind-session-dbus.c b/src/login/logind-session-dbus.c
index f793f99..5f6bafb 100644
--- a/src/login/logind-session-dbus.c
+++ b/src/login/logind-session-dbus.c
@@ -452,9 +452,7 @@ static DBusHandlerResult session_message_dispatch(
                         return bus_send_error_reply(connection, message, &error, -EINVAL);
 
                 dev = makedev(major, minor);
-                assert_cc(sizeof(unsigned long) >= sizeof(dev_t));
-
-                sd = hashmap_get(s->devices, ULONG_TO_PTR((unsigned long)dev));
+                sd = hashmap_get(s->devices, &dev);
                 if (sd) {
                         /* We don't allow retrieving a device multiple times.
                          * The related ReleaseDevice call is not ref-counted.
@@ -487,6 +485,7 @@ static DBusHandlerResult session_message_dispatch(
         } else if (dbus_message_is_method_call(message, "org.freedesktop.login1.Session", "ReleaseDevice")) {
                 SessionDevice *sd;
                 uint32_t major, minor;
+                dev_t dev;
 
                 if (!session_is_controller(s, bus_message_get_sender_with_fallback(message)))
                         return bus_send_error_reply(connection, message, NULL, -EPERM);
@@ -499,7 +498,8 @@ static DBusHandlerResult session_message_dispatch(
                                     DBUS_TYPE_INVALID))
                         return bus_send_error_reply(connection, message, &error, -EINVAL);
 
-                sd = hashmap_get(s->devices, ULONG_TO_PTR((unsigned long)makedev(major, minor)));
+                dev = makedev(major, minor);
+                sd = hashmap_get(s->devices, &dev);
                 if (!sd)
                         return bus_send_error_reply(connection, message, NULL, -ENODEV);
 
@@ -512,6 +512,7 @@ static DBusHandlerResult session_message_dispatch(
         } else if (dbus_message_is_method_call(message, "org.freedesktop.login1.Session", "PauseDeviceComplete")) {
                 SessionDevice *sd;
                 uint32_t major, minor;
+                dev_t dev;
 
                 if (!session_is_controller(s, bus_message_get_sender_with_fallback(message)))
                         return bus_send_error_reply(connection, message, NULL, -EPERM);
@@ -524,7 +525,8 @@ static DBusHandlerResult session_message_dispatch(
                                     DBUS_TYPE_INVALID))
                         return bus_send_error_reply(connection, message, &error, -EINVAL);
 
-                sd = hashmap_get(s->devices, ULONG_TO_PTR((unsigned long)makedev(major, minor)));
+                dev = makedev(major, minor);
+                sd = hashmap_get(s->devices, &dev);
                 if (!sd)
                         return bus_send_error_reply(connection, message, NULL, -ENODEV);
 
diff --git a/src/login/logind-session-device.c b/src/login/logind-session-device.c
index e92bb54..b45f9eb 100644
--- a/src/login/logind-session-device.c
+++ b/src/login/logind-session-device.c
@@ -369,9 +369,7 @@ int session_device_new(Session *s, dev_t dev, SessionDevice **out) {
         if (r < 0)
                 goto error;
 
-        assert_cc(sizeof(unsigned long) >= sizeof(dev_t));
-
-        r = hashmap_put(s->devices, ULONG_TO_PTR((unsigned long)sd->dev), sd);
+        r = hashmap_put(s->devices, &sd->dev, sd);
         if (r < 0) {
                 r = -ENOMEM;
                 goto error;
@@ -392,7 +390,7 @@ int session_device_new(Session *s, dev_t dev, SessionDevice **out) {
         return 0;
 
 error:
-        hashmap_remove(s->devices, ULONG_TO_PTR((unsigned long)sd->dev));
+        hashmap_remove(s->devices, &sd->dev);
         free(sd->node);
         free(sd);
         return r;
@@ -407,7 +405,7 @@ void session_device_free(SessionDevice *sd) {
 
         LIST_REMOVE(SessionDevice, sd_by_device, sd->device->session_devices, sd);
 
-        hashmap_remove(sd->session->devices, ULONG_TO_PTR((unsigned long)sd->dev));
+        hashmap_remove(sd->session->devices, &sd->dev);
 
         free(sd->node);
         free(sd);
diff --git a/src/login/logind-session.c b/src/login/logind-session.c
index eea0bfb..ce982ef 100644
--- a/src/login/logind-session.c
+++ b/src/login/logind-session.c
@@ -36,6 +36,21 @@
 #include "dbus-common.h"
 #include "logind-session.h"
 
+static unsigned devt_hash_func(const void *p) {
+        uint64_t u = *(const dev_t*)p;
+
+        return uint64_hash_func(&u);
+}
+
+static int devt_compare_func(const void *_a, const void *_b) {
+        dev_t a, b;
+
+        a = *(const dev_t*) _a;
+        b = *(const dev_t*) _b;
+
+        return a < b ? -1 : (a > b ? 1 : 0);
+}
+
 Session* session_new(Manager *m, const char *id) {
         Session *s;
 
@@ -53,7 +68,7 @@ Session* session_new(Manager *m, const char *id) {
                 return NULL;
         }
 
-        s->devices = hashmap_new(trivial_hash_func, trivial_compare_func);
+        s->devices = hashmap_new(devt_hash_func, devt_compare_func);
         if (!s->devices) {
                 free(s->state_file);
                 free(s);
-- 
1.8.4