text: /*
   * trace-event-python.  Feed trace events to an embedded Python interpreter.
   *
   * Copyright (C) 2010 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 <Python.h>
  
  #include <stdio.h>
  #include <stdlib.h>
  #include <string.h>
  #include <errno.h>
  
  #include "../../perf.h"
  #include "../evsel.h"
  #include "../util.h"
  #include "../event.h"
  #include "../thread.h"
  #include "../trace-event.h"
  
  PyMODINIT_FUNC initperf_trace_context(void);
  
  #define FTRACE_MAX_EVENT				\
  	((1 << (sizeof(unsigned short) * 8)) - 1)
  
  struct event_format *events[FTRACE_MAX_EVENT];
  
  #define MAX_FIELDS	64
  #define N_COMMON_FIELDS	7
  
  extern struct scripting_context *scripting_context;
  
  static char *cur_field_name;
  static int zero_flag_atom;
  
  static PyObject *main_module, *main_dict;
  
  static void handler_call_die(const char *handler_name)
  {
  	PyErr_Print();
  	Py_FatalError("problem in Python trace event handler");
  }
  
  /*
   * Insert val into into the dictionary and decrement the reference counter.
   * This is necessary for dictionaries since PyDict_SetItemString() does not 
   * steal a reference, as opposed to PyTuple_SetItem().
   */
  static void pydict_set_item_string_decref(PyObject *dict, const char *key, PyObject *val)
  {
  	PyDict_SetItemString(dict, key, val);
  	Py_DECREF(val);
  }
  
  static void define_value(enum print_arg_type field_type,
  			 const char *ev_name,
  			 const char *field_name,
  			 const char *field_value,
  			 const char *field_str)
  {
  	const char *handler_name = "define_flag_value";
  	PyObject *handler, *t, *retval;
  	unsigned long long value;
  	unsigned n = 0;
  
  	if (field_type == PRINT_SYMBOL)
  		handler_name = "define_symbolic_value";
  
  	t = PyTuple_New(4);
  	if (!t)
  		Py_FatalError("couldn't create Python tuple");
  
  	value = eval_flag(field_value);
  
  	PyTuple_SetItem(t, n++, PyString_FromString(ev_name));
  	PyTuple_SetItem(t, n++, PyString_FromString(field_name));
  	PyTuple_SetItem(t, n++, PyInt_FromLong(value));
  	PyTuple_SetItem(t, n++, PyString_FromString(field_str));
  
  	handler = PyDict_GetItemString(main_dict, handler_name);
  	if (handler && PyCallable_Check(handler)) {
  		retval = PyObject_CallObject(handler, t);
  		if (retval == NULL)
  			handler_call_die(handler_name);
  	}
  
  	Py_DECREF(t);
  }
  
  static void define_values(enum print_arg_type field_type,
  			  struct print_flag_sym *field,
  			  const char *ev_name,
  			  const char *field_name)
  {
  	define_value(field_type, ev_name, field_name, field->value,
  		     field->str);
  
  	if (field->next)
  		define_values(field_type, field->next, ev_name, field_name);
  }
  
  static void define_field(enum print_arg_type field_type,
  			 const char *ev_name,
  			 const char *field_name,
  			 const char *delim)
  {
  	const char *handler_name = "define_flag_field";
  	PyObject *handler, *t, *retval;
  	unsigned n = 0;
  
  	if (field_type == PRINT_SYMBOL)
  		handler_name = "define_symbolic_field";
  
  	if (field_type == PRINT_FLAGS)
  		t = PyTuple_New(3);
  	else
  		t = PyTuple_New(2);
  	if (!t)
  		Py_FatalError("couldn't create Python tuple");
  
  	PyTuple_SetItem(t, n++, PyString_FromString(ev_name));
  	PyTuple_SetItem(t, n++, PyString_FromString(field_name));
  	if (field_type == PRINT_FLAGS)
  		PyTuple_SetItem(t, n++, PyString_FromString(delim));
  
  	handler = PyDict_GetItemString(main_dict, handler_name);
  	if (handler && PyCallable_Check(handler)) {
  		retval = PyObject_CallObject(handler, t);
  		if (retval == NULL)
  			handler_call_die(handler_name);
  	}
  
  	Py_DECREF(t);
  }
  
  static void define_event_symbols(struct event_format *event,
  				 const char *ev_name,
  				 struct print_arg *args)
  {
  	switch (args->type) {
  	case PRINT_NULL:
  		break;
  	case PRINT_ATOM:
  		define_value(PRINT_FLAGS, ev_name, cur_field_name, "0",
  			     args->atom.atom);
  		zero_flag_atom = 0;
  		break;
  	case PRINT_FIELD:
  		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_field(PRINT_FLAGS, ev_name, cur_field_name,
  			     args->flags.delim);
  		define_values(PRINT_FLAGS, args->flags.flags, ev_name,
  			      cur_field_name);
  		break;
  	case PRINT_SYMBOL:
  		define_event_symbols(event, ev_name, args->symbol.field);
  		define_field(PRINT_SYMBOL, ev_name, cur_field_name, NULL);
  		define_values(PRINT_SYMBOL, args->symbol.symbols, ev_name,
  			      cur_field_name);
  		break;
  	case PRINT_HEX:
  		define_event_symbols(event, ev_name, args->hex.field);
  		define_event_symbols(event, ev_name, args->hex.size);
  		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:
  		/* gcc warns for these? */
  	case PRINT_BSTRING:
  	case PRINT_DYNAMIC_ARRAY:
  	case PRINT_FUNC:
  		/* we should warn... */
  		return;
  	}
  
  	if (args->next)
  		define_event_symbols(event, ev_name, args->next);
  }
  
  static inline struct event_format *find_cache_event(struct perf_evsel *evsel)
  {
  	static char ev_name[256];
  	struct event_format *event;
  	int type = evsel->attr.config;
  
  	/*
   	 * XXX: Do we really need to cache this since now we have evsel->tp_format
   	 * cached already? Need to re-read this "cache" routine that as well calls
   	 * define_event_symbols() :-\
   	 */
  	if (events[type])
  		return events[type];
  
  	events[type] = event = evsel->tp_format;
  	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 python_process_tracepoint(struct perf_sample *sample,
  				      struct perf_evsel *evsel,
  				      struct thread *thread,
  				      struct addr_location *al)
  {
  	PyObject *handler, *retval, *context, *t, *obj, *dict = NULL;
  	static char handler_name[256];
  	struct format_field *field;
  	unsigned long long val;
  	unsigned long s, ns;
  	struct event_format *event;
  	unsigned n = 0;
  	int pid;
  	int cpu = sample->cpu;
  	void *data = sample->raw_data;
  	unsigned long long nsecs = sample->time;
  	const char *comm = thread__comm_str(thread);
  
  	t = PyTuple_New(MAX_FIELDS);
  	if (!t)
  		Py_FatalError("couldn't create Python tuple");
  
  	event = find_cache_event(evsel);
  	if (!event)
  		die("ug! no event found for type %d", (int)evsel->attr.config);
  
  	pid = raw_field_value(event, "common_pid", data);
  
  	sprintf(handler_name, "%s__%s", event->system, event->name);
  
  	handler = PyDict_GetItemString(main_dict, handler_name);
  	if (handler && !PyCallable_Check(handler))
  		handler = NULL;
  	if (!handler) {
  		dict = PyDict_New();
  		if (!dict)
  			Py_FatalError("couldn't create Python dict");
  	}
  	s = nsecs / NSECS_PER_SEC;
  	ns = nsecs - s * NSECS_PER_SEC;
  
  	scripting_context->event_data = data;
  	scripting_context->pevent = evsel->tp_format->pevent;
  
  	context = PyCObject_FromVoidPtr(scripting_context, NULL);
  
  	PyTuple_SetItem(t, n++, PyString_FromString(handler_name));
  	PyTuple_SetItem(t, n++, context);
  
  	if (handler) {
  		PyTuple_SetItem(t, n++, PyInt_FromLong(cpu));
  		PyTuple_SetItem(t, n++, PyInt_FromLong(s));
  		PyTuple_SetItem(t, n++, PyInt_FromLong(ns));
  		PyTuple_SetItem(t, n++, PyInt_FromLong(pid));
  		PyTuple_SetItem(t, n++, PyString_FromString(comm));
  	} else {
  		pydict_set_item_string_decref(dict, "common_cpu", PyInt_FromLong(cpu));
  		pydict_set_item_string_decref(dict, "common_s", PyInt_FromLong(s));
  		pydict_set_item_string_decref(dict, "common_ns", PyInt_FromLong(ns));
  		pydict_set_item_string_decref(dict, "common_pid", PyInt_FromLong(pid));
  		pydict_set_item_string_decref(dict, "common_comm", PyString_FromString(comm));
  	}
  	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;
  			obj = PyString_FromString((char *)data + offset);
  		} else { /* FIELD_IS_NUMERIC */
  			val = read_size(event, data + field->offset,
  					field->size);
  			if (field->flags & FIELD_IS_SIGNED) {
  				if ((long long)val >= LONG_MIN &&
  				    (long long)val <= LONG_MAX)
  					obj = PyInt_FromLong(val);
  				else
  					obj = PyLong_FromLongLong(val);
  			} else {
  				if (val <= LONG_MAX)
  					obj = PyInt_FromLong(val);
  				else
  					obj = PyLong_FromUnsignedLongLong(val);
  			}
  		}
  		if (handler)
  			PyTuple_SetItem(t, n++, obj);
  		else
  			pydict_set_item_string_decref(dict, field->name, obj);
  
  	}
  	if (!handler)
  		PyTuple_SetItem(t, n++, dict);
  
  	if (_PyTuple_Resize(&t, n) == -1)
  		Py_FatalError("error resizing Python tuple");
  
  	if (handler) {
  		retval = PyObject_CallObject(handler, t);
  		if (retval == NULL)
  			handler_call_die(handler_name);
  	} else {
  		handler = PyDict_GetItemString(main_dict, "trace_unhandled");
  		if (handler && PyCallable_Check(handler)) {
  
  			retval = PyObject_CallObject(handler, t);
  			if (retval == NULL)
  				handler_call_die("trace_unhandled");
  		}
  		Py_DECREF(dict);
  	}
  
  	Py_DECREF(t);
  }
  
  static void python_process_general_event(struct perf_sample *sample,
  					 struct perf_evsel *evsel,
  					 struct thread *thread,
  					 struct addr_location *al)
  {
  	PyObject *handler, *retval, *t, *dict;
  	static char handler_name[64];
  	unsigned n = 0;
  
  	/*
  	 * Use the MAX_FIELDS to make the function expandable, though
  	 * currently there is only one item for the tuple.
  	 */
  	t = PyTuple_New(MAX_FIELDS);
  	if (!t)
  		Py_FatalError("couldn't create Python tuple");
  
  	dict = PyDict_New();
  	if (!dict)
  		Py_FatalError("couldn't create Python dictionary");
  
  	snprintf(handler_name, sizeof(handler_name), "%s", "process_event");
  
  	handler = PyDict_GetItemString(main_dict, handler_name);
  	if (!handler || !PyCallable_Check(handler))
  		goto exit;
  
  	pydict_set_item_string_decref(dict, "ev_name", PyString_FromString(perf_evsel__name(evsel)));
  	pydict_set_item_string_decref(dict, "attr", PyString_FromStringAndSize(
  			(const char *)&evsel->attr, sizeof(evsel->attr)));
  	pydict_set_item_string_decref(dict, "sample", PyString_FromStringAndSize(
  			(const char *)sample, sizeof(*sample)));
  	pydict_set_item_string_decref(dict, "raw_buf", PyString_FromStringAndSize(
  			(const char *)sample->raw_data, sample->raw_size));
  	pydict_set_item_string_decref(dict, "comm",
  			PyString_FromString(thread__comm_str(thread)));
  	if (al->map) {
  		pydict_set_item_string_decref(dict, "dso",
  			PyString_FromString(al->map->dso->name));
  	}
  	if (al->sym) {
  		pydict_set_item_string_decref(dict, "symbol",
  			PyString_FromString(al->sym->name));
  	}
  
  	PyTuple_SetItem(t, n++, dict);
  	if (_PyTuple_Resize(&t, n) == -1)
  		Py_FatalError("error resizing Python tuple");
  
  	retval = PyObject_CallObject(handler, t);
  	if (retval == NULL)
  		handler_call_die(handler_name);
  exit:
  	Py_DECREF(dict);
  	Py_DECREF(t);
  }
  
  static void python_process_event(union perf_event *event __maybe_unused,
  				 struct perf_sample *sample,
  				 struct perf_evsel *evsel,
  				 struct thread *thread,
  				 struct addr_location *al)
  {
  	switch (evsel->attr.type) {
  	case PERF_TYPE_TRACEPOINT:
  		python_process_tracepoint(sample, evsel, thread, al);
  		break;
  	/* Reserve for future process_hw/sw/raw APIs */
  	default:
  		python_process_general_event(sample, evsel, thread, al);
  	}
  }
  
  static int run_start_sub(void)
  {
  	PyObject *handler, *retval;
  	int err = 0;
  
  	main_module = PyImport_AddModule("__main__");
  	if (main_module == NULL)
  		return -1;
  	Py_INCREF(main_module);
  
  	main_dict = PyModule_GetDict(main_module);
  	if (main_dict == NULL) {
  		err = -1;
  		goto error;
  	}
  	Py_INCREF(main_dict);
  
  	handler = PyDict_GetItemString(main_dict, "trace_begin");
  	if (handler == NULL || !PyCallable_Check(handler))
  		goto out;
  
  	retval = PyObject_CallObject(handler, NULL);
  	if (retval == NULL)
  		handler_call_die("trace_begin");
  
  	Py_DECREF(retval);
  	return err;
  error:
  	Py_XDECREF(main_dict);
  	Py_XDECREF(main_module);
  out:
  	return err;
  }
  
  /*
   * Start trace script
   */
  static int python_start_script(const char *script, int argc, const char **argv)
  {
  	const char **command_line;
  	char buf[PATH_MAX];
  	int i, err = 0;
  	FILE *fp;
  
  	command_line = malloc((argc + 1) * sizeof(const char *));
  	command_line[0] = script;
  	for (i = 1; i < argc + 1; i++)
  		command_line[i] = argv[i - 1];
  
  	Py_Initialize();
  
  	initperf_trace_context();
  
  	PySys_SetArgv(argc + 1, (char **)command_line);
  
  	fp = fopen(script, "r");
  	if (!fp) {
  		sprintf(buf, "Can't open python script \"%s\"", script);
  		perror(buf);
  		err = -1;
  		goto error;
  	}
  
  	err = PyRun_SimpleFile(fp, script);
  	if (err) {
  		fprintf(stderr, "Error running python script %s\n", script);
  		goto error;
  	}
  
  	err = run_start_sub();
  	if (err) {
  		fprintf(stderr, "Error starting python script %s\n", script);
  		goto error;
  	}
  
  	free(command_line);
  
  	return err;
  error:
  	Py_Finalize();
  	free(command_line);
  
  	return err;
  }
  
  /*
   * Stop trace script
   */
  static int python_stop_script(void)
  {
  	PyObject *handler, *retval;
  	int err = 0;
  
  	handler = PyDict_GetItemString(main_dict, "trace_end");
  	if (handler == NULL || !PyCallable_Check(handler))
  		goto out;
  
  	retval = PyObject_CallObject(handler, NULL);
  	if (retval == NULL)
  		handler_call_die("trace_end");
  	else
  		Py_DECREF(retval);
  out:
  	Py_XDECREF(main_dict);
  	Py_XDECREF(main_module);
  	Py_Finalize();
  
  	return err;
  }
  
  static int python_generate_script(struct pevent *pevent, const char *outfile)
  {
  	struct event_format *event = NULL;
  	struct format_field *f;
  	char fname[PATH_MAX];
  	int not_first, count;
  	FILE *ofp;
  
  	sprintf(fname, "%s.py", outfile);
  	ofp = fopen(fname, "w");
  	if (ofp == NULL) {
  		fprintf(stderr, "couldn't open %s\n", fname);
  		return -1;
  	}
  	fprintf(ofp, "# perf script event handlers, "
  		"generated by perf script -g python\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 Python functions of the form "
  		"common_*(context).\n");
  
  	fprintf(ofp, "# See the perf-trace-python Documentation for the list "
  		"of available functions.\n\n");
  
  	fprintf(ofp, "import os\n");
  	fprintf(ofp, "import sys\n\n");
  
  	fprintf(ofp, "sys.path.append(os.environ['PERF_EXEC_PATH'] + \\\n");
  	fprintf(ofp, "\t'/scripts/python/Perf-Trace-Util/lib/Perf/Trace')\n");
  	fprintf(ofp, "\nfrom perf_trace_context import *\n");
  	fprintf(ofp, "from Core import *\n\n\n");
  
  	fprintf(ofp, "def trace_begin():\n");
  	fprintf(ofp, "\tprint \"in trace_begin\"\n\n");
  
  	fprintf(ofp, "def trace_end():\n");
  	fprintf(ofp, "\tprint \"in trace_end\"\n\n");
  
  	while ((event = trace_find_next_event(pevent, event))) {
  		fprintf(ofp, "def %s__%s(", event->system, event->name);
  		fprintf(ofp, "event_name, ");
  		fprintf(ofp, "context, ");
  		fprintf(ofp, "common_cpu,\n");
  		fprintf(ofp, "\tcommon_secs, ");
  		fprintf(ofp, "common_nsecs, ");
  		fprintf(ofp, "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");
  
  		fprintf(ofp, "\t\tprint_header(event_name, common_cpu, "
  			"common_secs, common_nsecs,\n\t\t\t"
  			"common_pid, common_comm)\n\n");
  
  		fprintf(ofp, "\t\tprint \"");
  
  		not_first = 0;
  		count = 0;
  
  		for (f = event->format.fields; f; f = f->next) {
  			if (not_first++)
  				fprintf(ofp, ", ");
  			if (count && count % 3 == 0) {
  				fprintf(ofp, "\" \\\n\t\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\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\t");
  
  			if (f->flags & FIELD_IS_FLAG) {
  				if ((count - 1) % 5 != 0) {
  					fprintf(ofp, "\n\t\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\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\n");
  	}
  
  	fprintf(ofp, "def trace_unhandled(event_name, context, "
  		"event_fields_dict):\n");
  
  	fprintf(ofp, "\t\tprint ' '.join(['%%s=%%s'%%(k,str(v))"
  		"for k,v in sorted(event_fields_dict.items())])\n\n");
  
  	fprintf(ofp, "def print_header("
  		"event_name, cpu, secs, nsecs, pid, comm):\n"
  		"\tprint \"%%-20s %%5u %%05u.%%09u %%8u %%-20s \" %% \\\n\t"
  		"(event_name, cpu, secs, nsecs, pid, comm),\n");
  
  	fclose(ofp);
  
  	fprintf(stderr, "generated Python script: %s\n", fname);
  
  	return 0;
  }
  
  struct scripting_ops python_scripting_ops = {
  	.name = "Python",
  	.start_script = python_start_script,
  	.stop_script = python_stop_script,
  	.process_event = python_process_event,
  	.generate_script = python_generate_script,
  };
  