/*

   +----------------------------------------------------------------------+

   | Copyright © The PHP Group and Contributors.                          |

   +----------------------------------------------------------------------+

   | This source file is subject to the Modified BSD License that is      |

   | bundled with this package in the file LICENSE, and is available      |

   | through the World Wide Web at <https://www.php.net/license/>.        |

   |                                                                      |

   | SPDX-License-Identifier: BSD-3-Clause                                |

   +----------------------------------------------------------------------+

 */

#include "php.h"

#if defined(HAVE_SYMLINK) || defined(PHP_WIN32)

#ifdef PHP_WIN32

#include <WinBase.h>

#endif

#include <stdlib.h>

#ifdef HAVE_UNISTD_H

#include <unistd.h>

#endif

#ifndef PHP_WIN32

#include <sys/stat.h>

#endif

#include <string.h>

#include <errno.h>

#include "php_string.h"

#ifndef VOLUME_NAME_NT

#define VOLUME_NAME_NT 0x2

#endif

#ifndef VOLUME_NAME_DOS

#define VOLUME_NAME_DOS 0x0

#endif

/* {{{ Return the target of a symbolic link */

PHP_FUNCTION(readlink)

{

  char *link;

  size_t link_len;

  char buff[MAXPATHLEN];

  ssize_t ret;

  ZEND_PARSE_PARAMETERS_START(1, 1)

    Z_PARAM_PATH(link, link_len)

  ZEND_PARSE_PARAMETERS_END();

  if (php_check_open_basedir(link)) {

    RETURN_FALSE;

  }

  ret = php_sys_readlink(link, buff, MAXPATHLEN-1);

  if (ret == -1) {

#ifdef PHP_WIN32

    php_error_docref(NULL, E_WARNING, "readlink failed to read the symbolic link (%s), error %ld", link, GetLastError());

#else

    php_error_docref(NULL, E_WARNING, "%s", strerror(errno));

#endif

    RETURN_FALSE;

  }

  /* Append NULL to the end of the string */

  buff[ret] = '\0';

  RETURN_STRINGL(buff, ret);

}

/* }}} */

/* {{{ Returns the st_dev field of the UNIX C stat structure describing the link */

PHP_FUNCTION(linkinfo)

{

  char *link;

  char *dirname;

  size_t link_len;

  zend_stat_t sb = {0};

  int ret;

  ZEND_PARSE_PARAMETERS_START(1, 1)

    Z_PARAM_PATH(link, link_len)

  ZEND_PARSE_PARAMETERS_END();

  if (UNEXPECTED(link_len == 0)) {

    zend_argument_must_not_be_empty_error(1);

    RETURN_THROWS();

  }

  dirname = estrndup(link, link_len);

  zend_dirname(dirname, link_len);

  if (php_check_open_basedir(dirname)) {

    efree(dirname);

    RETURN_FALSE;

  }

  ret = VCWD_LSTAT(link, &sb);

  if (ret == -1) {

    php_error_docref(NULL, E_WARNING, "%s", strerror(errno));

    efree(dirname);

    RETURN_LONG(Z_L(-1));

  }

  efree(dirname);

  RETURN_LONG((zend_long) sb.st_dev);

}

/* }}} */

/* {{{ Create a symbolic link */

PHP_FUNCTION(symlink)

{

  char *topath, *frompath;

  size_t topath_len, frompath_len;

  int ret;

  char source_p[MAXPATHLEN];

  char dest_p[MAXPATHLEN];

  char dirname[MAXPATHLEN];

  size_t len;

  ZEND_PARSE_PARAMETERS_START(2, 2)

    Z_PARAM_PATH(topath, topath_len)

    Z_PARAM_PATH(frompath, frompath_len)

  ZEND_PARSE_PARAMETERS_END();

  if (!expand_filepath(frompath, source_p)) {

    php_error_docref(NULL, E_WARNING, "No such file or directory");

    RETURN_FALSE;

  }

  memcpy(dirname, source_p, sizeof(source_p));

  len = zend_dirname(dirname, strlen(dirname));

  if (!expand_filepath_ex(topath, dest_p, dirname, len)) {

    php_error_docref(NULL, E_WARNING, "No such file or directory");

    RETURN_FALSE;

  }

  if (php_stream_locate_url_wrapper(source_p, NULL, STREAM_LOCATE_WRAPPERS_ONLY) ||

    php_stream_locate_url_wrapper(dest_p, NULL, STREAM_LOCATE_WRAPPERS_ONLY) )

  {

    php_error_docref(NULL, E_WARNING, "Unable to symlink to a URL");

    RETURN_FALSE;

  }

  if (php_check_open_basedir(dest_p)) {

    RETURN_FALSE;

  }

  if (php_check_open_basedir(source_p)) {

    RETURN_FALSE;

  }

  /* For the source, an expanded path must be used (in ZTS an other thread could have changed the CWD).

   * For the target the exact string given by the user must be used, relative or not, existing or not.

   * The target is relative to the link itself, not to the CWD. */

  ret = php_sys_symlink(topath, source_p);

  if (ret == -1) {

    php_error_docref(NULL, E_WARNING, "%s", strerror(errno));

    RETURN_FALSE;

  }

  RETURN_TRUE;

}

/* }}} */

/* {{{ Create a hard link */

PHP_FUNCTION(link)

{

  char *topath, *frompath;

  size_t topath_len, frompath_len;

  int ret;

  char source_p[MAXPATHLEN];

  char dest_p[MAXPATHLEN];

  ZEND_PARSE_PARAMETERS_START(2, 2)

    Z_PARAM_PATH(topath, topath_len)

    Z_PARAM_PATH(frompath, frompath_len)

  ZEND_PARSE_PARAMETERS_END();

  if (!expand_filepath(frompath, source_p) || !expand_filepath(topath, dest_p)) {

    php_error_docref(NULL, E_WARNING, "No such file or directory");

    RETURN_FALSE;

  }

  if (php_stream_locate_url_wrapper(source_p, NULL, STREAM_LOCATE_WRAPPERS_ONLY) ||

    php_stream_locate_url_wrapper(dest_p, NULL, STREAM_LOCATE_WRAPPERS_ONLY) )

  {

    php_error_docref(NULL, E_WARNING, "Unable to link to a URL");

    RETURN_FALSE;

  }

  if (php_check_open_basedir(dest_p)) {

    RETURN_FALSE;

  }

  if (php_check_open_basedir(source_p)) {

    RETURN_FALSE;

  }

#ifndef ZTS

  ret = php_sys_link(topath, frompath);

#else

  ret = php_sys_link(dest_p, source_p);

#endif

  if (ret == -1) {

    php_error_docref(NULL, E_WARNING, "%s", strerror(errno));

    RETURN_FALSE;

  }

  RETURN_TRUE;

}

/* }}} */

#endif