--- /dev/null
+/*
+ * trace-event-perl.  Feed perf trace events to an embedded Perl interpreter.
+ *
+ * Copyright (C) 2009 Tom Zanussi <tzanussi@gmail.com>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to the Free Software
+ *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ *
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <ctype.h>
+#include <errno.h>
+
+#include "../perf.h"
+#include "util.h"
+#include "trace-event.h"
+#include "trace-event-perl.h"
+
+INTERP my_perl;
+
+#define FTRACE_MAX_EVENT                               \
+       ((1 << (sizeof(unsigned short) * 8)) - 1)
+
+struct event *events[FTRACE_MAX_EVENT];
+
+static struct scripting_context *scripting_context;
+
+static char *cur_field_name;
+static int zero_flag_atom;
+
+static void define_symbolic_value(const char *ev_name,
+                                 const char *field_name,
+                                 const char *field_value,
+                                 const char *field_str)
+{
+       unsigned long long value;
+       dSP;
+
+       value = eval_flag(field_value);
+
+       ENTER;
+       SAVETMPS;
+       PUSHMARK(SP);
+
+       XPUSHs(sv_2mortal(newSVpv(ev_name, 0)));
+       XPUSHs(sv_2mortal(newSVpv(field_name, 0)));
+       XPUSHs(sv_2mortal(newSVuv(value)));
+       XPUSHs(sv_2mortal(newSVpv(field_str, 0)));
+
+       PUTBACK;
+       if (get_cv("main::define_symbolic_value", 0))
+               call_pv("main::define_symbolic_value", G_SCALAR);
+       SPAGAIN;
+       PUTBACK;
+       FREETMPS;
+       LEAVE;
+}
+
+static void define_symbolic_values(struct print_flag_sym *field,
+                                  const char *ev_name,
+                                  const char *field_name)
+{
+       define_symbolic_value(ev_name, field_name, field->value, field->str);
+       if (field->next)
+               define_symbolic_values(field->next, ev_name, field_name);
+}
+
+static void define_symbolic_field(const char *ev_name,
+                                 const char *field_name)
+{
+       dSP;
+
+       ENTER;
+       SAVETMPS;
+       PUSHMARK(SP);
+
+       XPUSHs(sv_2mortal(newSVpv(ev_name, 0)));
+       XPUSHs(sv_2mortal(newSVpv(field_name, 0)));
+
+       PUTBACK;
+       if (get_cv("main::define_symbolic_field", 0))
+               call_pv("main::define_symbolic_field", G_SCALAR);
+       SPAGAIN;
+       PUTBACK;
+       FREETMPS;
+       LEAVE;
+}
+
+static void define_flag_value(const char *ev_name,
+                             const char *field_name,
+                             const char *field_value,
+                             const char *field_str)
+{
+       unsigned long long value;
+       dSP;
+
+       value = eval_flag(field_value);
+
+       ENTER;
+       SAVETMPS;
+       PUSHMARK(SP);
+
+       XPUSHs(sv_2mortal(newSVpv(ev_name, 0)));
+       XPUSHs(sv_2mortal(newSVpv(field_name, 0)));
+       XPUSHs(sv_2mortal(newSVuv(value)));
+       XPUSHs(sv_2mortal(newSVpv(field_str, 0)));
+
+       PUTBACK;
+       if (get_cv("main::define_flag_value", 0))
+               call_pv("main::define_flag_value", G_SCALAR);
+       SPAGAIN;
+       PUTBACK;
+       FREETMPS;
+       LEAVE;
+}
+
+static void define_flag_values(struct print_flag_sym *field,
+                              const char *ev_name,
+                              const char *field_name)
+{
+       define_flag_value(ev_name, field_name, field->value, field->str);
+       if (field->next)
+               define_flag_values(field->next, ev_name, field_name);
+}
+
+static void define_flag_field(const char *ev_name,
+                             const char *field_name,
+                             const char *delim)
+{
+       dSP;
+
+       ENTER;
+       SAVETMPS;
+       PUSHMARK(SP);
+
+       XPUSHs(sv_2mortal(newSVpv(ev_name, 0)));
+       XPUSHs(sv_2mortal(newSVpv(field_name, 0)));
+       XPUSHs(sv_2mortal(newSVpv(delim, 0)));
+
+       PUTBACK;
+       if (get_cv("main::define_flag_field", 0))
+               call_pv("main::define_flag_field", G_SCALAR);
+       SPAGAIN;
+       PUTBACK;
+       FREETMPS;
+       LEAVE;
+}
+
+static void define_event_symbols(struct event *event,
+                                const char *ev_name,
+                                struct print_arg *args)
+{
+       switch (args->type) {
+       case PRINT_NULL:
+               break;
+       case PRINT_ATOM:
+               define_flag_value(ev_name, cur_field_name, "0",
+                                 args->atom.atom);
+               zero_flag_atom = 0;
+               break;
+       case PRINT_FIELD:
+               if (cur_field_name)
+                       free(cur_field_name);
+               cur_field_name = strdup(args->field.name);
+               break;
+       case PRINT_FLAGS:
+               define_event_symbols(event, ev_name, args->flags.field);
+               define_flag_field(ev_name, cur_field_name, args->flags.delim);
+               define_flag_values(args->flags.flags, ev_name, cur_field_name);
+               break;
+       case PRINT_SYMBOL:
+               define_event_symbols(event, ev_name, args->symbol.field);
+               define_symbolic_field(ev_name, cur_field_name);
+               define_symbolic_values(args->symbol.symbols, ev_name,
+                                      cur_field_name);
+               break;
+       case PRINT_STRING:
+               break;
+       case PRINT_TYPE:
+               define_event_symbols(event, ev_name, args->typecast.item);
+               break;
+       case PRINT_OP:
+               if (strcmp(args->op.op, ":") == 0)
+                       zero_flag_atom = 1;
+               define_event_symbols(event, ev_name, args->op.left);
+               define_event_symbols(event, ev_name, args->op.right);
+               break;
+       default:
+               /* we should warn... */
+               return;
+       }
+
+       if (args->next)
+               define_event_symbols(event, ev_name, args->next);
+}
+
+static inline struct event *find_cache_event(int type)
+{
+       static char ev_name[256];
+       struct event *event;
+
+       if (events[type])
+               return events[type];
+
+       events[type] = event = trace_find_event(type);
+       if (!event)
+               return NULL;
+
+       sprintf(ev_name, "%s::%s", event->system, event->name);
+
+       define_event_symbols(event, ev_name, event->print_fmt.args);
+
+       return event;
+}
+
+static void perl_process_event(int cpu, void *data,
+                              int size __attribute((unused)),
+                              unsigned long long nsecs, char *comm)
+{
+       struct format_field *field;
+       static char handler[256];
+       unsigned long long val;
+       unsigned long s, ns;
+       struct event *event;
+       int type;
+       int pid;
+
+       dSP;
+
+       type = trace_parse_common_type(data);
+
+       event = find_cache_event(type);
+       if (!event)
+               die("ug! no event found for type %d", type);
+
+       pid = trace_parse_common_pid(data);
+
+       sprintf(handler, "%s::%s", event->system, event->name);
+
+       s = nsecs / NSECS_PER_SEC;
+       ns = nsecs - s * NSECS_PER_SEC;
+
+       scripting_context->event_data = data;
+
+       ENTER;
+       SAVETMPS;
+       PUSHMARK(SP);
+
+       XPUSHs(sv_2mortal(newSVpv(handler, 0)));
+       XPUSHs(sv_2mortal(newSViv(PTR2IV(scripting_context))));
+       XPUSHs(sv_2mortal(newSVuv(cpu)));
+       XPUSHs(sv_2mortal(newSVuv(s)));
+       XPUSHs(sv_2mortal(newSVuv(ns)));
+       XPUSHs(sv_2mortal(newSViv(pid)));
+       XPUSHs(sv_2mortal(newSVpv(comm, 0)));
+
+       /* common fields other than pid can be accessed via xsub fns */
+
+       for (field = event->format.fields; field; field = field->next) {
+               if (field->flags & FIELD_IS_STRING) {
+                       int offset;
+                       if (field->flags & FIELD_IS_DYNAMIC) {
+                               offset = *(int *)(data + field->offset);
+                               offset &= 0xffff;
+                       } else
+                               offset = field->offset;
+                       XPUSHs(sv_2mortal(newSVpv((char *)data + offset, 0)));
+               } else { /* FIELD_IS_NUMERIC */
+                       val = read_size(data + field->offset, field->size);
+                       if (field->flags & FIELD_IS_SIGNED) {
+                               XPUSHs(sv_2mortal(newSViv(val)));
+                       } else {
+                               XPUSHs(sv_2mortal(newSVuv(val)));
+                       }
+               }
+       }
+
+       PUTBACK;
+       if (get_cv(handler, 0))
+               call_pv(handler, G_SCALAR);
+       else if (get_cv("main::trace_unhandled", 0)) {
+               XPUSHs(sv_2mortal(newSVpv(handler, 0)));
+               XPUSHs(sv_2mortal(newSViv(PTR2IV(scripting_context))));
+               XPUSHs(sv_2mortal(newSVuv(cpu)));
+               XPUSHs(sv_2mortal(newSVuv(nsecs)));
+               XPUSHs(sv_2mortal(newSViv(pid)));
+               XPUSHs(sv_2mortal(newSVpv(comm, 0)));
+               call_pv("main::trace_unhandled", G_SCALAR);
+       }
+       SPAGAIN;
+       PUTBACK;
+       FREETMPS;
+       LEAVE;
+}
+
+static void run_start_sub(void)
+{
+       dSP; /* access to Perl stack */
+       PUSHMARK(SP);
+
+       if (get_cv("main::trace_begin", 0))
+               call_pv("main::trace_begin", G_DISCARD | G_NOARGS);
+}
+
+/*
+ * Start trace script
+ */
+static int perl_start_script(const char *script)
+{
+       const char *command_line[2] = { "", NULL };
+
+       command_line[1] = script;
+
+       my_perl = perl_alloc();
+       perl_construct(my_perl);
+
+       if (perl_parse(my_perl, NULL, 2, (char **)command_line, (char **)NULL))
+               return -1;
+
+       perl_run(my_perl);
+       if (SvTRUE(ERRSV))
+               return -1;
+
+       run_start_sub();
+
+       fprintf(stderr, "perf trace started with Perl script %s\n\n", script);
+
+       return 0;
+}
+
+/*
+ * Stop trace script
+ */
+static int perl_stop_script(void)
+{
+       dSP; /* access to Perl stack */
+       PUSHMARK(SP);
+
+       if (get_cv("main::trace_end", 0))
+               call_pv("main::trace_end", G_DISCARD | G_NOARGS);
+
+       perl_destruct(my_perl);
+       perl_free(my_perl);
+
+       fprintf(stderr, "\nperf trace Perl script stopped\n");
+
+       return 0;
+}
+
+static int perl_generate_script(const char *outfile)
+{
+       struct event *event = NULL;
+       struct format_field *f;
+       char fname[PATH_MAX];
+       int not_first, count;
+       FILE *ofp;
+
+       sprintf(fname, "%s.pl", outfile);
+       ofp = fopen(fname, "w");
+       if (ofp == NULL) {
+               fprintf(stderr, "couldn't open %s\n", fname);
+               return -1;
+       }
+
+       fprintf(ofp, "# perf trace event handlers, "
+               "generated by perf trace -g perl\n");
+
+       fprintf(ofp, "# Licensed under the terms of the GNU GPL"
+               " License version 2\n\n");
+
+       fprintf(ofp, "# The common_* event handler fields are the most useful "
+               "fields common to\n");
+
+       fprintf(ofp, "# all events.  They don't necessarily correspond to "
+               "the 'common_*' fields\n");
+
+       fprintf(ofp, "# in the format files.  Those fields not available as "
+               "handler params can\n");
+
+       fprintf(ofp, "# be retrieved using Perl functions of the form "
+               "common_*($context).\n");
+
+       fprintf(ofp, "# See Context.pm for the list of available "
+               "functions.\n\n");
+
+       fprintf(ofp, "use lib \"$ENV{'PERF_EXEC_PATH'}/scripts/perl/"
+               "Perf-Trace-Util/lib\";\n");
+
+       fprintf(ofp, "use lib \"./Perf-Trace-Util/lib\";\n");
+       fprintf(ofp, "use Perf::Trace::Core;\n");
+       fprintf(ofp, "use Perf::Trace::Context;\n");
+       fprintf(ofp, "use Perf::Trace::Util;\n\n");
+
+       fprintf(ofp, "sub trace_begin\n{\n\t# optional\n}\n\n");
+       fprintf(ofp, "sub trace_end\n{\n\t# optional\n}\n\n");
+
+       while ((event = trace_find_next_event(event))) {
+               fprintf(ofp, "sub %s::%s\n{\n", event->system, event->name);
+               fprintf(ofp, "\tmy (");
+
+               fprintf(ofp, "$event_name, ");
+               fprintf(ofp, "$context, ");
+               fprintf(ofp, "$common_cpu, ");
+               fprintf(ofp, "$common_secs, ");
+               fprintf(ofp, "$common_nsecs,\n");
+               fprintf(ofp, "\t    $common_pid, ");
+               fprintf(ofp, "$common_comm,\n\t    ");
+
+               not_first = 0;
+               count = 0;
+
+               for (f = event->format.fields; f; f = f->next) {
+                       if (not_first++)
+                               fprintf(ofp, ", ");
+                       if (++count % 5 == 0)
+                               fprintf(ofp, "\n\t    ");
+
+                       fprintf(ofp, "$%s", f->name);
+               }
+               fprintf(ofp, ") = @_;\n\n");
+
+               fprintf(ofp, "\tprint_header($event_name, $common_cpu, "
+                       "$common_secs, $common_nsecs,\n\t             "
+                       "$common_pid, $common_comm);\n\n");
+
+               fprintf(ofp, "\tprintf(\"");
+
+               not_first = 0;
+               count = 0;
+
+               for (f = event->format.fields; f; f = f->next) {
+                       if (not_first++)
+                               fprintf(ofp, ", ");
+                       if (count && count % 4 == 0) {
+                               fprintf(ofp, "\".\n\t       \"");
+                       }
+                       count++;
+
+                       fprintf(ofp, "%s=", f->name);
+                       if (f->flags & FIELD_IS_STRING ||
+                           f->flags & FIELD_IS_FLAG ||
+                           f->flags & FIELD_IS_SYMBOLIC)
+                               fprintf(ofp, "%%s");
+                       else if (f->flags & FIELD_IS_SIGNED)
+                               fprintf(ofp, "%%d");
+                       else
+                               fprintf(ofp, "%%u");
+               }
+
+               fprintf(ofp, "\\n\",\n\t       ");
+
+               not_first = 0;
+               count = 0;
+
+               for (f = event->format.fields; f; f = f->next) {
+                       if (not_first++)
+                               fprintf(ofp, ", ");
+
+                       if (++count % 5 == 0)
+                               fprintf(ofp, "\n\t       ");
+
+                       if (f->flags & FIELD_IS_FLAG) {
+                               if ((count - 1) % 5 != 0) {
+                                       fprintf(ofp, "\n\t       ");
+                                       count = 4;
+                               }
+                               fprintf(ofp, "flag_str(\"");
+                               fprintf(ofp, "%s::%s\", ", event->system,
+                                       event->name);
+                               fprintf(ofp, "\"%s\", $%s)", f->name,
+                                       f->name);
+                       } else if (f->flags & FIELD_IS_SYMBOLIC) {
+                               if ((count - 1) % 5 != 0) {
+                                       fprintf(ofp, "\n\t       ");
+                                       count = 4;
+                               }
+                               fprintf(ofp, "symbol_str(\"");
+                               fprintf(ofp, "%s::%s\", ", event->system,
+                                       event->name);
+                               fprintf(ofp, "\"%s\", $%s)", f->name,
+                                       f->name);
+                       } else
+                               fprintf(ofp, "$%s", f->name);
+               }
+
+               fprintf(ofp, ");\n");
+               fprintf(ofp, "}\n\n");
+       }
+
+       fprintf(ofp, "sub trace_unhandled\n{\n\tmy ($event_name, $context, "
+               "$common_cpu, $common_secs, $common_nsecs,\n\t    "
+               "$common_pid, $common_comm) = @_;\n\n");
+
+       fprintf(ofp, "\tprint_header($event_name, $common_cpu, "
+               "$common_secs, $common_nsecs,\n\t             $common_pid, "
+               "$common_comm);\n}\n\n");
+
+       fprintf(ofp, "sub print_header\n{\n"
+               "\tmy ($event_name, $cpu, $secs, $nsecs, $pid, $comm) = @_;\n\n"
+               "\tprintf(\"%%-20s %%5u %%05u.%%09u %%8u %%-20s \",\n\t       "
+               "$event_name, $cpu, $secs, $nsecs, $pid, $comm);\n}");
+
+       fclose(ofp);
+
+       fprintf(stderr, "generated Perl script: %s\n", fname);
+
+       return 0;
+}
+
+struct scripting_ops perl_scripting_ops = {
+       .name = "Perl",
+       .start_script = perl_start_script,
+       .stop_script = perl_stop_script,
+       .process_event = perl_process_event,
+       .generate_script = perl_generate_script,
+};
+
+#ifdef NO_LIBPERL
+void setup_perl_scripting(void)
+{
+       fprintf(stderr, "Perl scripting not supported."
+               "  Install libperl-dev[el] and rebuild perf to get it.\n");
+}
+#else
+void setup_perl_scripting(void)
+{
+       int err;
+       err = script_spec_register("Perl", &perl_scripting_ops);
+       if (err)
+               die("error registering Perl script extension");
+
+       err = script_spec_register("pl", &perl_scripting_ops);
+       if (err)
+               die("error registering pl script extension");
+
+       scripting_context = malloc(sizeof(struct scripting_context));
+}
+#endif