path: root/lib/runtime_tools/c_src/dyntrace.c

/*
 * %CopyrightBegin%
 *
 * Copyright Scott Lystig Fritchie 2011-2016. All Rights Reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 * %CopyrightEnd%
 */

/*
 * Purpose:  Dynamically loadable NIF library for DTrace
 */



#include "erl_nif.h"
#include "config.h"
#include "sys.h"
#include "dtrace-wrapper.h"
#if defined(USE_DYNAMIC_TRACE) && (defined(USE_DTRACE) || defined(USE_SYSTEMTAP))
#define HAVE_USE_DTRACE 1
#endif

void dtrace_nifenv_str(ErlNifEnv *env, char *process_buf);
void get_string_maybe(ErlNifEnv *env, const ERL_NIF_TERM term, char **ptr, char *buf, int bufsiz);
#ifdef HAVE_USE_DTRACE
ERL_NIF_TERM erl_nif_user_trace_s1(ErlNifEnv* env, int argc, const ERL_NIF_TERM argv[]);
ERL_NIF_TERM erl_nif_user_trace_i4s4(ErlNifEnv* env, int argc, const ERL_NIF_TERM argv[]);
#endif

#ifdef VALGRIND
    #  include <valgrind/memcheck.h>
#endif

#ifdef __GNUC__
    #  define INLINE __inline__
#else
    #  define INLINE
#endif

#define MESSAGE_BUFSIZ 1024

/* NIF interface declarations */
static int load(ErlNifEnv* env, void** priv_data, ERL_NIF_TERM load_info);

/* The NIFs: */
static ERL_NIF_TERM available(ErlNifEnv* env, int argc, const ERL_NIF_TERM argv[]);
static ERL_NIF_TERM user_trace_s1(ErlNifEnv* env, int argc, const ERL_NIF_TERM argv[]);
static ERL_NIF_TERM user_trace_i4s4(ErlNifEnv* env, int argc, const ERL_NIF_TERM argv[]);
static ERL_NIF_TERM user_trace_n(ErlNifEnv* env, int argc, const ERL_NIF_TERM argv[]);

static ErlNifFunc nif_funcs[] = {
    {"available", 0, available},
    {"user_trace_s1", 1, user_trace_s1},
    {"user_trace_i4s4", 9, user_trace_i4s4},
    {"user_trace_n", 10, user_trace_n}
};

ERL_NIF_INIT(dyntrace, nif_funcs, load, NULL, NULL, NULL)

static ERL_NIF_TERM atom_true;
static ERL_NIF_TERM atom_false;
static ERL_NIF_TERM atom_error;
static ERL_NIF_TERM atom_not_available;
static ERL_NIF_TERM atom_badarg;
static ERL_NIF_TERM atom_ok;

static int load(ErlNifEnv* env, void** priv_data, ERL_NIF_TERM load_info)
{
    atom_true = enif_make_atom(env,"true");
    atom_false = enif_make_atom(env,"false");
    atom_error = enif_make_atom(env,"error");
    atom_not_available = enif_make_atom(env,"not_available");
    atom_badarg = enif_make_atom(env,"badarg");
    atom_ok = enif_make_atom(env,"ok");

    return 0;
}

static ERL_NIF_TERM available(ErlNifEnv* env, int argc, const ERL_NIF_TERM argv[])
{
#ifdef	HAVE_USE_DTRACE
    return atom_true;
#else
    return atom_false;
#endif
}

static ERL_NIF_TERM user_trace_s1(ErlNifEnv* env, int argc, const ERL_NIF_TERM argv[])
{
#ifdef	HAVE_USE_DTRACE
    return erl_nif_user_trace_s1(env, argc, argv);
#else
    return atom_error;
#endif
}

static ERL_NIF_TERM user_trace_i4s4(ErlNifEnv* env, int argc, const ERL_NIF_TERM argv[])
{
#ifdef	HAVE_USE_DTRACE
    return erl_nif_user_trace_i4s4(env, argc, argv);
#else
    return atom_error;
#endif
}

static ERL_NIF_TERM user_trace_n(ErlNifEnv* env, int argc, const ERL_NIF_TERM argv[])
{
#ifdef	HAVE_USE_DTRACE
    return erl_nif_user_trace_n(env, argc, argv);
#else
    return atom_error;
#endif
}