2005-09-06 Martin Hunt <hunt@redhat.com>

	* tapset/context.stp: Add function target().
	* stapfuncs.5.in (target): Document it.
	* elaborate.h (struct systemtap_session): Add cmd and target_pid to
	the struct.
	* main.cxx (usage): Add secriptions of "-c" and "-x" options.
	(main): Set s.cmd and s.target_pid.
	* buildrun.cxx (stringify): Copy this utility func here too.
	(run_pass): Add new options to set cmd and pid to the stpd
	command line.

6 files changed, 54 insertions, 3 deletions

diff --git a/ChangeLog b/ChangeLog
index 8a9f14d3..40f398b0 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,15 @@
+2005-09-06  Martin Hunt  <hunt@redhat.com>
+
+	* tapset/context.stp: Add function target().
+	* stapfuncs.5.in (target): Document it.
+	* elaborate.h (struct systemtap_session): Add cmd and target_pid to
+	the struct.
+	* main.cxx (usage): Add secriptions of "-c" and "-x" options.
+	(main): Set s.cmd and s.target_pid.
+	* buildrun.cxx (stringify): Copy this utility func here too.
+	(run_pass): Add new options to set cmd and pid to the stpd
+	command line.
+
 2005-09-06  Frank Ch. Eigler  <fche@redhat.com>
 
 	* tapsets.cxx (emit_probe_entries): Disable fault_handler for now.
diff --git a/buildrun.cxx b/buildrun.cxx
index 867d0d0e..130f4a1b 100644
--- a/buildrun.cxx
+++ b/buildrun.cxx
@@ -92,6 +92,15 @@ compile_pass (systemtap_session& s)
 }
 
 
+template <typename T>
+static string
+stringify(T t)
+{
+  ostringstream s;
+  s << t;
+  return s.str ();
+}
+
 
 int
 run_pass (systemtap_session& s)
@@ -114,8 +123,15 @@ run_pass (systemtap_session& s)
       string stpd_cmd = string("/usr/bin/sudo ") 
         + string(PKGLIBDIR) + "/stpd "
 	+ "-r " // disable relayfs
-        + (s.verbose ? "" : "-q ")
-        + s.tmpdir + "/" + s.module_name + ".ko";
+        + (s.verbose ? "" : "-q ");
+
+      if (s.cmd != "")
+	stpd_cmd += "-c \"" + s.cmd + "\" ";
+
+      if (s.target_pid)
+	stpd_cmd += "-t " + stringify(s.target_pid) + " ";
+
+      stpd_cmd += s.tmpdir + "/" + s.module_name + ".ko";
 
       if (s.verbose) clog << "Running " << stpd_cmd << endl;
       rc = system (stpd_cmd.c_str ());
diff --git a/elaborate.h b/elaborate.h
index 43816e61..6482952c 100644
--- a/elaborate.h
+++ b/elaborate.h
@@ -206,6 +206,8 @@ struct systemtap_session
   std::string kernel_release;
   std::string runtime_path;
   std::string module_name;
+  std::string cmd;
+  int target_pid;
   int last_pass;
   bool test_mode;
   bool verbose;
diff --git a/main.cxx b/main.cxx
index adf1136f..c6663655 100644
--- a/main.cxx
+++ b/main.cxx
@@ -78,6 +78,8 @@ usage (systemtap_session& s)
     << "   -m MODULE  set probe module name, instead of" << endl
     <<      "              " << s.module_name << endl
     << "   -o FILE    send output to file instead of stdout" << endl
+    << "   -c CMD     start the probes, run CMD, and exit when it finishes" << endl
+    << "   -x PID     sets target() to PID" << endl
     ;
   // -d: dump safety-related external references
 
@@ -116,6 +118,8 @@ main (int argc, char * const argv [])
   s.last_pass = 5;
   s.module_name = "stap_" + stringify(getuid()) + "_" + stringify(time(0));
   s.keep_tmpdir = false;
+  s.cmd = "";
+  s.target_pid = 0;
 
   const char* s_p = getenv ("SYSTEMTAP_TAPSET");
   if (s_p != NULL)
@@ -131,7 +135,7 @@ main (int argc, char * const argv [])
 
   while (true)
     {
-      int grc = getopt (argc, argv, "hVvp:I:e:o:tR:r:m:kg");
+      int grc = getopt (argc, argv, "hVvp:I:e:o:tR:r:m:kgc:x:");
       if (grc < 0)
         break;
       switch (grc)
@@ -192,6 +196,14 @@ main (int argc, char * const argv [])
           s.guru_mode = true;
           break;
 
+	case 'c':
+	  s.cmd = string (optarg);
+	  break;
+
+	case 'x':
+	  s.target_pid = atoi(optarg);
+	  break;
+
         case 'h':
         default:
           usage (s);
diff --git a/stapfuncs.5.in b/stapfuncs.5.in
index dbecf0d3..77514e28 100644
--- a/stapfuncs.5.in
+++ b/stapfuncs.5.in
@@ -150,6 +150,10 @@ pp:string ()
 Return the probe point associated with the currently running probe handler,
 including alias and wildcard expansion effects.
 
+.TP
+target:long ()
+Returns the pid of the target process.
+
 .SH FILES
 .nh
 .IR /usr/share/systemtap/tapset
diff --git a/tapset/context.stp b/tapset/context.stp
index 3e776547..bb4004bb 100644
--- a/tapset/context.stp
+++ b/tapset/context.stp
@@ -92,3 +92,8 @@ function print_stack(stk:string) %{
 function pp:string () %{
 	strlcpy (THIS->__retvalue, CONTEXT->probe_point, MAXSTRINGLEN);
 %}
+
+function target:long () %{
+        THIS->__retvalue = _stp_target;
+%}
+