/* 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.

 */

#include "uv.h"

#include "internal.h"

#include <stdlib.h>

#include <string.h>

struct uv__process_title {

  char* str;

  size_t len;  /* Length of the current process title. */

  size_t cap;  /* Maximum capacity. Computed once in uv_setup_args(). */

};

extern void uv__set_process_title(const char* title);

static uv_mutex_t process_title_mutex;

static uv_once_t process_title_mutex_once = UV_ONCE_INIT;

static struct uv__process_title process_title;

static void* args_mem;

static void init_process_title_mutex_once(void) {

  uv_mutex_init(&process_title_mutex);

}

char** uv_setup_args(int argc, char** argv) {

  struct uv__process_title pt;

  char** new_argv;

  size_t size;

  char* s;

  int i;

  if (argc <= 0)

    return argv;

  pt.str = argv[0];

  pt.len = strlen(argv[0]);

  pt.cap = pt.len + 1;

  /* Calculate how much memory we need for the argv strings. */

  size = pt.cap;

  for (i = 1; i < argc; i++)

    size += strlen(argv[i]) + 1;

  /* Add space for the argv pointers. */

  size += (argc + 1) * sizeof(char*);

  new_argv = uv__malloc(size);

  if (new_argv == NULL)

    return argv;

  /* Copy over the strings and set up the pointer table. */

  i = 0;

  s = (char*) &new_argv[argc + 1];

  size = pt.cap;

  goto loop;

  for (/* empty */; i < argc; i++) {

    size = strlen(argv[i]) + 1;

  loop:

    memcpy(s, argv[i], size);

    new_argv[i] = s;

    s += size;

  }

  new_argv[i] = NULL;

  /* argv is not adjacent on z/os, we use just argv[0] on that platform. */

#ifndef __MVS__

  pt.cap = argv[i - 1] + size - argv[0];

#endif

  args_mem = new_argv;

  process_title = pt;

  return new_argv;

}

int uv_set_process_title(const char* title) {

  struct uv__process_title* pt;

  size_t len;

  /* If uv_setup_args wasn't called or failed, we can't continue. */

  if (args_mem == NULL)

    return UV_ENOBUFS;

  pt = &process_title;

  len = strlen(title);

  uv_once(&process_title_mutex_once, init_process_title_mutex_once);

  uv_mutex_lock(&process_title_mutex);

  if (len >= pt->cap) {

    len = 0;

    if (pt->cap > 0)

      len = pt->cap - 1;

  }

  memcpy(pt->str, title, len);

  memset(pt->str + len, '\0', pt->cap - len);

  pt->len = len;

  uv_mutex_unlock(&process_title_mutex);

  return 0;

}

int uv_get_process_title(char* buffer, size_t size) {

  if (buffer == NULL || size == 0)

    return UV_EINVAL;

  /* If uv_setup_args wasn't called or failed, we can't continue. */

  if (args_mem == NULL)

    return UV_ENOBUFS;

  uv_once(&process_title_mutex_once, init_process_title_mutex_once);

  uv_mutex_lock(&process_title_mutex);

  if (size <= process_title.len) {

    uv_mutex_unlock(&process_title_mutex);

    return UV_ENOBUFS;

  }

  if (process_title.len != 0)

    memcpy(buffer, process_title.str, process_title.len + 1);

  buffer[process_title.len] = '\0';

  uv_mutex_unlock(&process_title_mutex);

  return 0;

}

void uv__process_title_cleanup(void) {

  uv__free(args_mem);  /* Keep valgrind happy. */

  args_mem = NULL;

}