/*

 * Temp file utilities for CUPS.

 *

 * Copyright © 2007-2018 by Apple Inc.

 * Copyright © 1997-2006 by Easy Software Products.

 *

 * These coded instructions, statements, and computer programs are the

 * property of Apple Inc. and are protected by Federal copyright

 * law.  Distribution and use rights are outlined in the file "LICENSE.txt"

 * which should have been included with this file.  If this file is

 * missing or damaged, see the license at "http://www.cups.org/".

 *

 * This file is subject to the Apple OS-Developed Software exception.

 */

/*

 * Include necessary headers...

 */

#include "cups-private.h"

#include <stdlib.h>

#include <fcntl.h>

#include <sys/stat.h>

#if defined(_WIN32) || defined(__EMX__)

#  include <io.h>

#else

#  include <unistd.h>

#endif /* _WIN32 || __EMX__ */

/*

 * 'cupsTempFd()' - Creates a temporary file.

 *

 * The temporary filename is returned in the filename buffer.

 * The temporary file is opened for reading and writing.

 */

int         /* O - New file descriptor or -1 on error */

cupsTempFd(char *filename,    /* I - Pointer to buffer */

           int  len)      /* I - Size of buffer */

{

  int   fd;     /* File descriptor for temp file */

  int   tries;      /* Number of tries */

  const char  *tmpdir;    /* TMPDIR environment var */

#if defined(__APPLE__) || defined(_WIN32)

  char    tmppath[1024];    /* Temporary directory */

#endif /* __APPLE__ || _WIN32 */

#ifdef _WIN32

  DWORD   curtime;    /* Current time */

#else

  struct timeval curtime;   /* Current time */

#endif /* _WIN32 */

 /*

  * See if TMPDIR is defined...

  */

#ifdef _WIN32

  if ((tmpdir = getenv("TEMP")) == NULL)

  {

    GetTempPath(sizeof(tmppath), tmppath);

    tmpdir = tmppath;

  }

#elif defined(__APPLE__)

 /*

  * On macOS and iOS, the TMPDIR environment variable is not always the best

  * location to place temporary files due to sandboxing.  Instead, the confstr

  * function should be called to get the proper per-user, per-process TMPDIR

  * value.

  */

  if ((tmpdir = getenv("TMPDIR")) != NULL && access(tmpdir, W_OK))

    tmpdir = NULL;

  if (!tmpdir)

  {

    if (confstr(_CS_DARWIN_USER_TEMP_DIR, tmppath, sizeof(tmppath)))

      tmpdir = tmppath;

    else

      tmpdir = "/private/tmp";    /* This should never happen */

  }

#else

 /*

  * Previously we put root temporary files in the default CUPS temporary

  * directory under /var/spool/cups.  However, since the scheduler cleans

  * out temporary files there and runs independently of the user apps, we

  * don't want to use it unless specifically told to by cupsd.

  */

  if ((tmpdir = getenv("TMPDIR")) == NULL)

    tmpdir = "/tmp";

#endif /* _WIN32 */

 /*

  * Make the temporary name using the specified directory...

  */

  tries = 0;

  do

  {

#ifdef _WIN32

   /*

    * Get the current time of day...

    */

    curtime =  GetTickCount() + tries;

   /*

    * Format a string using the hex time values...

    */

    snprintf(filename, (size_t)len - 1, "%s/%05lx%08lx", tmpdir, GetCurrentProcessId(), curtime);

#else

   /*

    * Get the current time of day...

    */

    gettimeofday(&curtime, NULL);

   /*

    * Format a string using the hex time values...

    */

    snprintf(filename, (size_t)len - 1, "%s/%05x%08x", tmpdir, (unsigned)getpid(), (unsigned)(curtime.tv_sec + curtime.tv_usec + tries));

#endif /* _WIN32 */

   /*

    * Open the file in "exclusive" mode, making sure that we don't

    * stomp on an existing file or someone's symlink crack...

    */

#ifdef _WIN32

    fd = open(filename, _O_CREAT | _O_RDWR | _O_TRUNC | _O_BINARY,

              _S_IREAD | _S_IWRITE);

#elif defined(O_NOFOLLOW)

    fd = open(filename, O_RDWR | O_CREAT | O_EXCL | O_NOFOLLOW, 0600);

#else

    fd = open(filename, O_RDWR | O_CREAT | O_EXCL, 0600);

#endif /* _WIN32 */

    if (fd < 0 && errno != EEXIST)

      break;

    tries ++;

  }

  while (fd < 0 && tries < 1000);

 /*

  * Return the file descriptor...

  */

  return (fd);

}

/*

 * 'cupsTempFile()' - Generates a temporary filename.

 *

 * The temporary filename is returned in the filename buffer.

 * This function is deprecated and will no longer generate a temporary

 * filename - use @link cupsTempFd@ or @link cupsTempFile2@ instead.

 *

 * @deprecated@

 */

char *          /* O - Filename or @code NULL@ on error */

cupsTempFile(char *filename,    /* I - Pointer to buffer */

             int  len)      /* I - Size of buffer */

{

  (void)len;

  if (filename)

    *filename = '\0';

  return (NULL);

}

/*

 * 'cupsTempFile2()' - Creates a temporary CUPS file.

 *

 * The temporary filename is returned in the filename buffer.

 * The temporary file is opened for writing.

 *

 * @since CUPS 1.2/macOS 10.5@

 */

cups_file_t *       /* O - CUPS file or @code NULL@ on error */

cupsTempFile2(char *filename,   /* I - Pointer to buffer */

              int  len)     /* I - Size of buffer */

{

  cups_file_t *file;      /* CUPS file */

  int   fd;     /* File descriptor */

  if ((fd = cupsTempFd(filename, len)) < 0)

    return (NULL);

  else if ((file = cupsFileOpenFd(fd, "w")) == NULL)

  {

    close(fd);

    unlink(filename);

    return (NULL);

  }

  else

    return (file);

}