patch from Tobias Roth: put pid in lockfile + remove stale lockfile; added special commands and shortcuts info to the man page

git-svn-id: svn+ssh://svn.berlios.de/svnroot/repos/slim/trunk@94 7c53e7cc-98ea-0310-8f1f-a0b24da60408

app.cpp

@@ -17,6 +17,8 @@
 #include <cstring>
 #include <cstdio>
 
+#include <iostream>
+#include <fstream>
 #include <sstream>
 #include <vector>
 #include <algorithm>
@@ -723,17 +725,40 @@ void App::setBackground(const string& themedir) {
     XFlush(Dpy);
 }
 
-// Lock or die!
+// Check if there is a lockfile and a corresponding process
 void App::GetLock() {
-    int fd;
-    fd=open(cfg.getOption("lockfile").c_str(),O_WRONLY | O_CREAT | O_EXCL);
-    if (fd<0 && errno==EEXIST) {
-        cerr << APPNAME << ": It appears there is another instance of the program already running" <<endl
-            << "If not, try to remove the lockfile: " << cfg.getOption("lockfile") <<endl;
-        exit(ERR_EXIT);
-    } else if (fd < 0) {
-        cerr << APPNAME << ": Could not accesss lock file: " << cfg.getOption("lockfile") << endl;
-        exit(ERR_EXIT);
+    std::ifstream lockfile(cfg.getOption("lockfile").c_str());
+    if (!lockfile) {
+        // no lockfile present, create one
+        std::ofstream lockfile(cfg.getOption("lockfile").c_str(), ios_base::out);
+        if (!lockfile) {
+            cerr << APPNAME << ": Could not create lock file: " << cfg.getOption("lockfile").c_str() << std::endl;
+            exit(ERR_EXIT);
+        }
+        lockfile << getpid() << std::endl;
+        lockfile.close();
+    } else {
+        // lockfile present, read pid from it
+        int pid = 0;
+        lockfile >> pid;
+        lockfile.close();
+        if (pid > 0) {
+            // see if process with this pid exists
+            int ret = kill(pid, 0);
+            if (ret == 0 || (ret == -1 && errno == EPERM) ) {
+                cerr << APPNAME << ": Another instance of the program is already running with PID " << pid << std::endl;
+                exit(0);
+            } else {
+                cerr << APPNAME << ": Stale lockfile found, removing it" << std::endl;
+                std::ofstream lockfile(cfg.getOption("lockfile").c_str(), ios_base::out);
+                if (!lockfile) {
+                    cerr << APPNAME << ": Could not create new lock file: " << cfg.getOption("lockfile") << std::endl;
+                    exit(ERR_EXIT);
+                }
+                lockfile << getpid() << std::endl;
+                lockfile.close();
+            }
+        }
     }
 }
 

slim.1

@@ -1,5 +1,5 @@
 ." Text automatically generated by txt2man-1.4.7
-.TH slim 1 "May 15, 2005" "" ""
+.TH slim 1 "January 09, 2006" "" ""
 .SH NAME
 \fBslim \fP- Simple LogIn Manager
 \fB
@@ -15,29 +15,29 @@ of a graphical session by entring username and password in a login screen.
 .SH OPTIONS
 .TP
 .B
--d
+\fB-d\fP
 run as a daemon
 .TP
 .B
--p /path/to/theme
+\fB-p\fP /path/to/theme
 display a preview of the theme. An already running X11 session
 is required for theme preview.
 .TP
 .B
--h
+\fB-h\fP
 display a brief help message
 .TP
 .B
--v
+\fB-v\fP
 display version information
 .SH EXAMPLES
 .TP
 .B
-\fBslim\fP -d
+\fBslim\fP \fB-d\fP
 run \fBslim\fP in daemon mode
 .TP
 .B
-\fBslim\fP -p /usr/share/\fBslim\fP/themes/default
+\fBslim\fP \fB-p\fP /usr/share/\fBslim\fP/themes/default
 preview of the default theme
 .SH STARTING SLIM AT BOOT
 Please refer to documentation of your Operating System to make \fBslim\fP
@@ -45,6 +45,45 @@ automatically startup after the system boots.
 .SH CONFIGURATION
 Global configuration is stored in the /etc/slim.conf file. See the comments
 inside the file for a detailed explanation of the \fIoptions\fP.
+.SH USAGE AND SPECIAL USERNAMES
+When started, \fBslim\fP will show a login panel; enter the username and
+password of the user you want to login as.
+.PP
+Special usernames:
+.TP
+.B
+console
+open a xterm console
+.TP
+.B
+exit
+quit \fBslim\fP
+.TP
+.B
+halt
+shutdown the machine
+.TP
+.B
+reboot
+reboot the machine
+.TP
+.B
+suspend
+power-suspend the machine
+.PP
+See the configuration file for customizing the above commands.
+The 'halt' and 'reboot' commands need the root password, this may
+change in future releases.
+.PP
+Shortcuts:
+.TP
+.B
+F11
+executes a custom command (by default takes a screenshot)  
+.TP
+.B
+F1
+choose session type (see configuration file and xinitrc.sample)
 .SH AUTHORS 
 Simone Rota <sip@varlock.com>
 .PP