perf trace: Add Perl scripting support

Implement trace_scripting_ops to make Perl a supported perf
trace scripting language.

Additionally adds code that allows Perl trace scripts to access
the 'flag' and 'symbolic' (__print_flags(), __print_symbolic())
field information parsed from the trace format files.

Also adds the Perl implementation of the generate_script()
trace_scripting_op, which creates a ready-to-run perf trace Perl
script based on existing trace data.  Scripts generated by this
implementation print out all the fields for each event mentioned
in perf.data (and will detect and generate the proper scripting
code for 'flag' and 'symbolic' fields), and will additionally
generate handlers for the special 'trace_unhandled',
'trace_begin' and 'trace_end' handlers.  Script authors can
simply remove the printing code to implement their own custom
event handling.

Signed-off-by: Tom Zanussi <tzanussi@gmail.com>
Cc: fweisbec@gmail.com
Cc: rostedt@goodmis.org
Cc: anton@samba.org
Cc: hch@infradead.org
LKML-Reference: <1259133352-23685-4-git-send-email-tzanussi@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/tools/perf/util/trace-event-perl.h b/tools/perf/util/trace-event-perl.h
new file mode 100644
index 0000000..6c94fa9
--- /dev/null
+++ b/tools/perf/util/trace-event-perl.h
@@ -0,0 +1,42 @@
+#ifndef __PERF_TRACE_EVENT_PERL_H
+#define __PERF_TRACE_EVENT_PERL_H
+#ifdef NO_LIBPERL
+typedef int INTERP;
+#define dSP
+#define ENTER
+#define SAVETMPS
+#define PUTBACK
+#define SPAGAIN
+#define FREETMPS
+#define LEAVE
+#define SP
+#define ERRSV
+#define G_SCALAR		(0)
+#define G_DISCARD		(0)
+#define G_NOARGS		(0)
+#define PUSHMARK(a)
+#define SvTRUE(a)		(0)
+#define XPUSHs(s)
+#define sv_2mortal(a)
+#define newSVpv(a,b)
+#define newSVuv(a)
+#define newSViv(a)
+#define get_cv(a,b)		(0)
+#define call_pv(a,b)		(0)
+#define perl_alloc()		(0)
+#define perl_construct(a)	(0)
+#define perl_parse(a,b,c,d,e)	(0)
+#define perl_run(a)		(0)
+#define perl_destruct(a)	(0)
+#define perl_free(a)		(0)
+#else
+#include <EXTERN.h>
+#include <perl.h>
+typedef PerlInterpreter * INTERP;
+#endif
+
+struct scripting_context {
+	void *event_data;
+};
+
+#endif /* __PERF_TRACE_EVENT_PERL_H */