cups/tempfile.c

   1 /*
   2  * "$Id: tempfile.c 6039 2006-10-17 02:24:34Z mike $"
   3  *
   4  *   Temp file utilities for the Common UNIX Printing System (CUPS).
   5  *
   6  *   Copyright 1997-2006 by Easy Software Products.
   7  *
   8  *   These coded instructions, statements, and computer programs are the
   9  *   property of Easy Software Products and are protected by Federal
  10  *   copyright law.  Distribution and use rights are outlined in the file
  11  *   "LICENSE.txt" which should have been included with this file.  If this
  12  *   file is missing or damaged please contact Easy Software Products
  13  *   at:
  14  *
  15  *       Attn: CUPS Licensing Information
  16  *       Easy Software Products
  17  *       44141 Airport View Drive, Suite 204
  18  *       Hollywood, Maryland 20636 USA
  19  *
  20  *       Voice: (301) 373-9600
  21  *       EMail: cups-info@cups.org
  22  *         WWW: http://www.cups.org
  23  *
  24  *   This file is subject to the Apple OS-Developed Software exception.
  25  *
  26  * Contents:
  27  *
  28  *   cupsTempFd()    - Creates a temporary file.
  29  *   cupsTempFile()  - Generates a temporary filename.
  30  *   cupsTempFile2() - Creates a temporary CUPS file.
  31  */
  32
  33 /*
  34  * Include necessary headers...
  35  */
  36
  37 #include "globals.h"
  38 #include "debug.h"
  39 #include <stdlib.h>
  40 #include <errno.h>
  41 #include <fcntl.h>
  42 #include <sys/stat.h>
  43 #if defined(WIN32) || defined(__EMX__)
  44 #  include <io.h>
  45 #else
  46 #  include <unistd.h>
  47 #endif /* WIN32 || __EMX__ */
  48
  49
  50 /*
  51  * 'cupsTempFd()' - Creates a temporary file.
  52  *
  53  * The temporary filename is returned in the filename buffer.
  54  * The temporary file is opened for reading and writing.
  55  */
  56
  57 int                                     /* O - New file descriptor or -1 on error */
  58 cupsTempFd(char *filename,              /* I - Pointer to buffer */
  59            int  len)                    /* I - Size of buffer */
  60 {
  61   int           fd;                     /* File descriptor for temp file */
  62   int           tries;                  /* Number of tries */
  63   const char    *tmpdir;                /* TMPDIR environment var */
  64 #ifdef WIN32
  65   char          tmppath[1024];          /* Windows temporary directory */
  66   DWORD         curtime;                /* Current time */
  67 #else
  68   struct timeval curtime;               /* Current time */
  69 #endif /* WIN32 */
  70
  71
  72  /*
  73   * See if TMPDIR is defined...
  74   */
  75
  76 #ifdef WIN32
  77   if ((tmpdir = getenv("TEMP")) == NULL)
  78   {
  79     GetTempPath(sizeof(tmppath), tmppath);
  80     tmpdir = tmppath;
  81   }
  82 #else
  83   if ((tmpdir = getenv("TMPDIR")) == NULL)
  84   {
  85    /*
  86     * Put root temp files in restricted temp directory...
  87     */
  88
  89     if (getuid() == 0)
  90       tmpdir = CUPS_REQUESTS "/tmp";
  91     else
  92       tmpdir = "/tmp";
  93   }
  94 #endif /* WIN32 */
  95
  96  /*
  97   * Make the temporary name using the specified directory...
  98   */
  99
 100   tries = 0;
 101
 102   do
 103   {
 104 #ifdef WIN32
 105    /*
 106     * Get the current time of day...
 107     */
 108
 109     curtime =  GetTickCount() + tries;
 110
 111    /*
 112     * Format a string using the hex time values...
 113     */
 114
 115     snprintf(filename, len - 1, "%s/%05lx%08lx", tmpdir,
 116              GetCurrentProcessId(), curtime);
 117 #else
 118    /*
 119     * Get the current time of day...
 120     */
 121
 122     gettimeofday(&curtime, NULL);
 123
 124    /*
 125     * Format a string using the hex time values...
 126     */
 127
 128     snprintf(filename, len - 1, "%s/%08lx%05lx", tmpdir,
 129              (unsigned long)curtime.tv_sec, (unsigned long)curtime.tv_usec);
 130 #endif /* WIN32 */
 131
 132    /*
 133     * Open the file in "exclusive" mode, making sure that we don't
 134     * stomp on an existing file or someone's symlink crack...
 135     */
 136
 137 #ifdef WIN32
 138     fd = open(filename, _O_CREAT | _O_RDWR | _O_TRUNC | _O_BINARY,
 139               _S_IREAD | _S_IWRITE);
 140 #elif defined(O_NOFOLLOW)
 141     fd = open(filename, O_RDWR | O_CREAT | O_EXCL | O_NOFOLLOW, 0600);
 142 #else
 143     fd = open(filename, O_RDWR | O_CREAT | O_EXCL, 0600);
 144 #endif /* WIN32 */
 145
 146     if (fd < 0 && errno != EEXIST)
 147       break;
 148
 149     tries ++;
 150   }
 151   while (fd < 0 && tries < 1000);
 152
 153  /*
 154   * Return the file descriptor...
 155   */
 156
 157   return (fd);
 158 }
 159
 160
 161 /*
 162  * 'cupsTempFile()' - Generates a temporary filename.
 163  *
 164  * The temporary filename is returned in the filename buffer.
 165  * This function is deprecated - use cupsTempFd() or cupsTempFile2()
 166  * instead.
 167  *
 168  * @deprecated@
 169  */
 170
 171 char *                                  /* O - Filename or NULL on error */
 172 cupsTempFile(char *filename,            /* I - Pointer to buffer */
 173              int  len)                  /* I - Size of buffer */
 174 {
 175   int           fd;                     /* File descriptor for temp file */
 176   _cups_globals_t *cg = _cupsGlobals(); /* Pointer to library globals */
 177
 178
 179  /*
 180   * See if a filename was specified...
 181   */
 182
 183   if (filename == NULL)
 184   {
 185     filename = cg->tempfile;
 186     len      = sizeof(cg->tempfile);
 187   }
 188
 189  /*
 190   * Create the temporary file...
 191   */
 192
 193   if ((fd = cupsTempFd(filename, len)) < 0)
 194     return (NULL);
 195
 196  /*
 197   * Close the temp file - it'll be reopened later as needed...
 198   */
 199
 200   close(fd);
 201
 202  /*
 203   * Return the temp filename...
 204   */
 205
 206   return (filename);
 207 }
 208
 209
 210 /*
 211  * 'cupsTempFile2()' - Creates a temporary CUPS file.
 212  *
 213  * The temporary filename is returned in the filename buffer.
 214  * The temporary file is opened for writing.
 215  *
 216  * @since CUPS 1.2@
 217  */
 218
 219 cups_file_t *                           /* O - CUPS file or NULL on error */
 220 cupsTempFile2(char *filename,           /* I - Pointer to buffer */
 221               int  len)                 /* I - Size of buffer */
 222 {
 223   cups_file_t   *file;                  /* CUPS file */
 224   int           fd;                     /* File descriptor */
 225
 226
 227   if ((fd = cupsTempFd(filename, len)) < 0)
 228     return (NULL);
 229   else if ((file = cupsFileOpenFd(fd, "w")) == NULL)
 230   {
 231     close(fd);
 232     unlink(filename);
 233     return (NULL);
 234   }
 235   else
 236     return (file);
 237 }
 238
 239
 240 /*
 241  * End of "$Id: tempfile.c 6039 2006-10-17 02:24:34Z mike $".
 242  */