/* Copyright Joyent, Inc. and other Node contributors. All rights reserved.

 *

 * Permission is hereby granted, free of charge, to any person obtaining a copy

 * of this software and associated documentation files (the "Software"), to

 * deal in the Software without restriction, including without limitation the

 * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or

 * sell copies of the Software, and to permit persons to whom the Software is

 * furnished to do so, subject to the following conditions:

 *

 * The above copyright notice and this permission notice shall be included in

 * all copies or substantial portions of the Software.

 *

 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR

 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,

 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE

 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER

 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING

 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS

 * IN THE SOFTWARE.

 */

/* This benchmark spawns itself 1000 times. */

#include "task.h"

#include "uv.h"

static uv_loop_t* loop;

static int N = 1000;

static int done;

static uv_process_t process;

static uv_process_options_t options;

static char exepath[1024];

static size_t exepath_size = 1024;

static char* args[3];

static uv_pipe_t out;

#define OUTPUT_SIZE 1024

static char output[OUTPUT_SIZE];

static int output_used;

static int process_open;

static int pipe_open;

static void spawn(void);

static void maybe_spawn(void) {

  if (process_open == 0 && pipe_open == 0) {

    done++;

    if (done < N) {

      spawn();

    }

  }

}

static void process_close_cb(uv_handle_t* handle) {

  ASSERT(process_open == 1);

  process_open = 0;

  maybe_spawn();

}

static void exit_cb(uv_process_t* process,

                    int64_t exit_status,

                    int term_signal) {

  ASSERT(exit_status == 42);

  ASSERT(term_signal == 0);

  uv_close((uv_handle_t*)process, process_close_cb);

}

static void on_alloc(uv_handle_t* handle,

                     size_t suggested_size,

                     uv_buf_t* buf) {

  buf->base = output + output_used;

  buf->len = OUTPUT_SIZE - output_used;

}

static void pipe_close_cb(uv_handle_t* pipe) {

  ASSERT(pipe_open == 1);

  pipe_open = 0;

  maybe_spawn();

}

static void on_read(uv_stream_t* pipe, ssize_t nread, const uv_buf_t* buf) {

  if (nread > 0) {

    ASSERT(pipe_open == 1);

    output_used += nread;

  } else if (nread < 0) {

    if (nread == UV_EOF) {

      uv_close((uv_handle_t*)pipe, pipe_close_cb);

    }

  }

}

static void spawn(void) {

  uv_stdio_container_t stdio[2];

  int r;

  ASSERT(process_open == 0);

  ASSERT(pipe_open == 0);

  args[0] = exepath;

  args[1] = "spawn_helper";

  args[2] = NULL;

  options.file = exepath;

  options.args = args;

  options.exit_cb = exit_cb;

  uv_pipe_init(loop, &out, 0);

  options.stdio = stdio;

  options.stdio_count = 2;

  options.stdio[0].flags = UV_IGNORE;

  options.stdio[1].flags = UV_CREATE_PIPE | UV_WRITABLE_PIPE;

  options.stdio[1].data.stream = (uv_stream_t*)&out;

  r = uv_spawn(loop, &process, &options);

  ASSERT(r == 0);

  process_open = 1;

  pipe_open = 1;

  output_used = 0;

  r = uv_read_start((uv_stream_t*) &out, on_alloc, on_read);

  ASSERT(r == 0);

}

BENCHMARK_IMPL(spawn) {

  int r;

  static int64_t start_time, end_time;

  loop = uv_default_loop();

  r = uv_exepath(exepath, &exepath_size);

  ASSERT(r == 0);

  exepath[exepath_size] = '\0';

  uv_update_time(loop);

  start_time = uv_now(loop);

  spawn();

  r = uv_run(loop, UV_RUN_DEFAULT);

  ASSERT(r == 0);

  uv_update_time(loop);

  end_time = uv_now(loop);

  fprintf(stderr, "spawn: %.0f spawns/s\n",

          (double) N / (double) (end_time - start_time) * 1000.0);

  fflush(stderr);

  MAKE_VALGRIND_HAPPY();

  return 0;

}