Merge pull request #155 from sateler/run_in_foreground_option

Added flag to run in foreground, no daemon (--no-daemon switch)

man/logkeys.8

@@ -7,6 +7,8 @@ logkeys \- a GNU/Linux keylogger that works!
            [\fB--no-func-keys\fR] [\fB--no-timestamps\fR] 
 .br
            [\fB--post-http=\fIURL\fR] [\fB--post-size=\fISIZE\fR]
+.br
+           [\fB--no-daemon\fR]
 .br
 .B logkeys \fB-k\fR
 .br
@@ -133,6 +135,11 @@ by a (PHP) script.
 The file is sent with header \fIContent-Type: multipart/form-data\fR as file, so it
 is accessible in PHP via $_FILES['file'] variable.
 
+.TP
+\fB-\-no-daemon\fR
+When this option is set, logkeys runs in the foreground.
+Useful when printing output to stdout.
+
 .SH FILES
 .TP
 \fB/var/log/logkeys.log\fR

src/args.cc

@@ -33,6 +33,7 @@ struct arguments
 #define FLAG_POST_HTTP        0x8  // post log to remote HTTP server, --post-http switch
 #define FLAG_POST_IRC        0x10  // post log to remote IRC server, --post-irc switch
 #define FLAG_POST_SIZE       0x20  // post log to remote HTTP or IRC server when log of size optarg, --post-size
+#define FLAG_NO_DAEMON       0x40  // don't daemonize process, stay in foreground, --no-daemon switch
 } args = {0};  // default all args to 0x0 or ""
 
 
@@ -54,6 +55,7 @@ void process_command_line_arguments(int argc, char **argv)
     {"post-http",     required_argument, &flags, FLAG_POST_HTTP},
     {"post-irc",      required_argument, &flags, FLAG_POST_IRC},
     {"post-size",     required_argument, &flags, FLAG_POST_SIZE},
+    {"no-daemon",     no_argument,       &flags, FLAG_NO_DAEMON},
     {0}
   };
   

src/logkeys.cc

@@ -422,12 +422,14 @@ int main(int argc, char **argv)
   
   set_signal_handling();
   
-  int nochdir = 0;
-  if (args.logfile[0] != '/')
-       nochdir = 1;  // don't chdir (logfile specified with relative path)
-  int noclose = 1;  // don't close streams (stderr used)
-  if (daemon(nochdir, noclose) == -1)  // become daemon
-    error(EXIT_FAILURE, errno, "Failed to become daemon");
+  if (!(args.flags & FLAG_NO_DAEMON)) {
+    int nochdir = 0;
+    if (args.logfile[0] != '/')
+         nochdir = 1;  // don't chdir (logfile specified with relative path)
+    int noclose = 1;  // don't close streams (stderr used)
+    if (daemon(nochdir, noclose) == -1)  // become daemon
+      error(EXIT_FAILURE, errno, "Failed to become daemon");
+  }
   close(STDIN_FILENO);
   // leave stderr open
   if (args.logfile != "-") {
@@ -460,7 +462,9 @@ int main(int argc, char **argv)
   
   // now we need those privileges back in order to create system-wide PID_FILE
   seteuid(0); setegid(0);
-  create_PID_file();
+  if (!(args.flags & FLAG_NO_DAEMON)) {
+    create_PID_file();
+  }
   
   // now we've got everything we need, finally drop privileges by becoming 'nobody'
   //setegid(65534); seteuid(65534);   // commented-out, I forgot why xD

src/usage.cc

@@ -30,6 +30,7 @@ void usage()
 "      --post-http=URL       POST log to URL as multipart/form-data file\n"
 //"      --post-irc=FORMAT     FORMAT is nick_or_channel@server:port\n"
 "      --post-size=SIZE      post log file when size equals SIZE [500k]\n"
+"      --no-daemon           run in foreground\n"
 "\n"
 "Examples: logkeys -s -m mylang.map -o ~/.secret-keys.log\n"
 "          logkeys -s -d event6\n"