hal/hald/linux2/probing shared.h,1.2,1.3

[David Zeuthen]

Update of /cvs/hal/hal/hald/linux2/probing
In directory gabe:/tmp/cvs-serv20696/hald/linux2/probing

Modified Files:
	shared.h 
Log Message:
2006-02-08  David Zeuthen  <davidz at redhat.com>

        Patch from Matthew Garrett <mjg59 at srcf.ucam.org>.

        Two patches attached: 1) Changes the ACPI addon to report the type
        of button pressed as well as the fact that a button has been
        pressed. 2) Adds a keyboard addon. The included fdi file will bind
        it to anything that has type input.keyboard. It adds the
        capability "button" to the keyboard devices, and on any keypress
        checks the key against a table. If the key is found there, a
        ButtonPressed event is generated with the name of the key in the
        details field (one exception - KEY_SUSPEND is given the name
        "hibernate").

        There's a couple of extra features that could be added (export a
        list of the available keys, for instance - not very helpful on
        PS/2, but useful on USB), but could these be applied as is for
        now?

        * hald/linux2/probing/shared.h: Move drop_privileges here so other
        code can use it too.

        * hald/linux2/addons/Makefile.am: Add build rules for
        hald-addon-keybaord

        * hald/linux2/addons/addon-acpi.c: Also send button.type as part
        of the event

        * hald/linux2/addons/addon-keyboard.c: New file. Also set
        button.type to "" and button.has_state to FALSE




Index: shared.h
===================================================================
RCS file: /cvs/hal/hal/hald/linux2/probing/shared.h,v
retrieving revision 1.2
retrieving revision 1.3
diff -u -d -r1.2 -r1.3
--- shared.h	16 Feb 2005 22:25:20 -0000	1.2
+++ shared.h	8 Feb 2006 13:54:44 -0000	1.3
@@ -5,6 +5,11 @@
 #include <time.h>
 #include <sys/time.h>
 
+#include <sys/types.h>
+#include <unistd.h>
+#include <pwd.h>
+#include <grp.h>
+
 static dbus_bool_t is_verbose = FALSE;
 
 static void
@@ -47,4 +52,37 @@
 		_dbg ("%s:%d: " format "\n", __FILE__, __LINE__, ## arg); \
 	} while (0)
 
+/** Drop all but necessary privileges.  Set the running user id to HAL_USER and
+ *  group to HAL_GROUP
+ */
+static 
+void drop_privileges () { 
+    struct passwd *pw = NULL; 
+    struct group *gr = NULL;
+
+    /* determine user id */
+    pw = getpwnam (HAL_USER);
+    if (!pw)  {
+        printf ("drop_privileges: user " HAL_USER " does not exist");
+        exit (-1);
+    }
+
+    /* determine primary group id */
+    gr = getgrnam (HAL_GROUP);
+    if(!gr) {
+        printf("drop_privileges: group " HAL_GROUP " does not exist");
+        exit (-1);
+    }
+
+    if( setgid (gr->gr_gid) ) {
+        printf ("drop_privileges: could not set group id");
+        exit (-1);
+    }
+
+    if( setuid (pw->pw_uid)) {
+        printf ("drop_privileges: could not set user id");
+        exit (-1);
+    }
+}
+
 #endif