sal/osl/unx/tempfile.cxx

   1 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
   2 /*
   3  * This file is part of the LibreOffice project.
   4  *
   5  * This Source Code Form is subject to the terms of the Mozilla Public
   6  * License, v. 2.0. If a copy of the MPL was not distributed with this
   7  * file, You can obtain one at http://mozilla.org/MPL/2.0/.
   8  *
   9  * This file incorporates work covered by the following license notice:
  10  *
  11  *   Licensed to the Apache Software Foundation (ASF) under one or more
  12  *   contributor license agreements. See the NOTICE file distributed
  13  *   with this work for additional information regarding copyright
  14  *   ownership. The ASF licenses this file to you under the Apache
  15  *   License, Version 2.0 (the "License"); you may not use this file
  16  *   except in compliance with the License. You may obtain a copy of
  17  *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
  18  */
  19
  20 #include <stdlib.h>
  21 #include <sys/stat.h>
  22 #include <sys/time.h>
  23 #include <unistd.h>
  24 #include <osl/file.h>
  25 #include <osl/thread.h>
  26 #include <rtl/ustrbuf.h>
  27 #include <osl/diagnose.h>
  28 #include <sal/macros.h>
  29
  30 #include "file_url.hxx"
  31 #include "file_impl.hxx"
  32
  33 #include <cassert>
  34
  35 oslFileError SAL_CALL osl_getTempDirURL( rtl_uString** pustrTempDir )
  36 {
  37     oslFileError error;
  38     /* described in environ(7) */
  39     const char *pValue = getenv( "TMPDIR" );
  40     rtl_uString *ustrTempPath = nullptr;
  41
  42     if ( !pValue )
  43         pValue = getenv( "TEMP" );
  44
  45     if ( !pValue )
  46         pValue = getenv( "TMP" );
  47
  48     if ( !pValue )
  49         pValue = "/tmp";
  50
  51     auto nLen = strlen(pValue);
  52     while (nLen > 1 && pValue[nLen - 1] == '/') // Allow path consisting of single "/"
  53         --nLen;
  54     rtl_string2UString( &ustrTempPath, pValue, nLen, osl_getThreadTextEncoding(), OSTRING_TO_OUSTRING_CVTFLAGS );
  55     assert(ustrTempPath);
  56     error = osl_getFileURLFromSystemPath( ustrTempPath, pustrTempDir );
  57     rtl_uString_release( ustrTempPath );
  58
  59     return error;
  60 }
  61
  62 /******************************************************************
  63  * Generates a random unique file name. We're using the scheme
  64  * from the standard c-lib function mkstemp to generate a more
  65  * or less random unique file name
  66  *
  67  * @param rand_name
  68  *        receives the random name
  69  ******************************************************************/
  70
  71 const char LETTERS[]        = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890";
  72 const int  COUNT_OF_LETTERS = SAL_N_ELEMENTS(LETTERS) - 1;
  73
  74 #define RAND_NAME_LENGTH 6
  75
  76 static void osl_gen_random_name_impl_(rtl_uString** rand_name)
  77 {
  78     static uint64_t value;
  79
  80     char     buffer[RAND_NAME_LENGTH];
  81     struct   timeval tv;
  82     uint64_t v;
  83     int      i;
  84
  85     gettimeofday(&tv, nullptr);
  86
  87     value += (static_cast<uint64_t>(tv.tv_usec) << 16) ^ tv.tv_sec ^ getpid();
  88
  89     v = value;
  90
  91     for (i = 0; i < RAND_NAME_LENGTH; i++)
  92     {
  93         buffer[i] = LETTERS[v % COUNT_OF_LETTERS];
  94         v        /= COUNT_OF_LETTERS;
  95     }
  96
  97     rtl_string2UString(
  98             rand_name,
  99             buffer,
 100             RAND_NAME_LENGTH,
 101             RTL_TEXTENCODING_ASCII_US,
 102             OSTRING_TO_OUSTRING_CVTFLAGS);
 103
 104     assert(*rand_name);
 105 }
 106
 107 /*****************************************************************
 108  * Helper function
 109  * Either use the directory provided or the result of
 110  * osl_getTempDirUrl and return it as system path and file url
 111  ****************************************************************/
 112
 113 static oslFileError osl_setup_base_directory_impl_(
 114     rtl_uString*  pustrDirectoryURL,
 115     rtl_uString** ppustr_base_dir)
 116 {
 117     rtl_uString* dir_url = nullptr;
 118     rtl_uString* dir     = nullptr;
 119     oslFileError error   = osl_File_E_None;
 120
 121     if (pustrDirectoryURL)
 122         rtl_uString_assign(&dir_url, pustrDirectoryURL);
 123     else
 124         error = osl_getTempDirURL(&dir_url);
 125
 126     if (error == osl_File_E_None)
 127     {
 128         error = getSystemPathFromFileURL_Ex(dir_url, &dir);
 129         rtl_uString_release(dir_url);
 130     }
 131
 132     if (error == osl_File_E_None)
 133     {
 134         rtl_uString_assign(ppustr_base_dir, dir);
 135         rtl_uString_release(dir);
 136     }
 137
 138     return error;
 139 }
 140
 141 /*****************************************************************
 142  * osl_setup_createTempFile_impl
 143  * validate input parameter, setup variables
 144  ****************************************************************/
 145
 146  static oslFileError osl_setup_createTempFile_impl_(
 147      rtl_uString*   pustrDirectoryURL,
 148     oslFileHandle* pHandle,
 149     rtl_uString**  ppustrTempFileURL,
 150     rtl_uString**  ppustr_base_dir,
 151     bool*      b_delete_on_close)
 152  {
 153     oslFileError osl_error;
 154
 155     OSL_PRECOND(((nullptr != pHandle) || (nullptr != ppustrTempFileURL)), "Invalid parameter!");
 156
 157     if ((pHandle == nullptr) && (ppustrTempFileURL == nullptr))
 158     {
 159         osl_error = osl_File_E_INVAL;
 160     }
 161     else
 162     {
 163         osl_error = osl_setup_base_directory_impl_(
 164             pustrDirectoryURL, ppustr_base_dir);
 165
 166         *b_delete_on_close = (ppustrTempFileURL == nullptr);
 167     }
 168
 169     return osl_error;
 170  }
 171
 172 /*****************************************************************
 173  * Create a unique file in the specified directory and return
 174  * its name
 175  ****************************************************************/
 176
 177 static oslFileError osl_create_temp_file_impl_(
 178     const rtl_uString* pustr_base_directory,
 179     oslFileHandle* file_handle,
 180     rtl_uString** ppustr_temp_file_name)
 181 {
 182     rtl_uString*        rand_name        = nullptr;
 183     sal_uInt32          len_base_dir     = 0;
 184     rtl_uString*        tmp_file_path    = nullptr;
 185     rtl_uString*        tmp_file_url     = nullptr;
 186     sal_Int32           capacity         = 0;
 187     oslFileError        osl_error        = osl_File_E_None;
 188     sal_Int32           offset_file_name;
 189     const sal_Unicode*  puchr;
 190
 191     OSL_PRECOND(pustr_base_directory, "Invalid Parameter");
 192     OSL_PRECOND(file_handle, "Invalid Parameter");
 193     OSL_PRECOND(ppustr_temp_file_name, "Invalid Parameter");
 194
 195     len_base_dir = rtl_uString_getLength(pustr_base_directory);
 196
 197     rtl_uString_new_WithLength(
 198         &tmp_file_path,
 199         (len_base_dir + 1 + RAND_NAME_LENGTH));
 200     capacity = len_base_dir + 1 + RAND_NAME_LENGTH;
 201
 202     rtl_uStringbuffer_insert(
 203         &tmp_file_path,
 204         &capacity,
 205         0,
 206         rtl_uString_getStr(const_cast<rtl_uString*>(pustr_base_directory)),
 207         len_base_dir);
 208
 209     offset_file_name = len_base_dir;
 210
 211     puchr = rtl_uString_getStr(tmp_file_path);
 212
 213     /* ensure that the last character is a '/' */
 214
 215     if (puchr[len_base_dir - 1] != '/')
 216     {
 217         rtl_uStringbuffer_insert_ascii(
 218             &tmp_file_path,
 219             &capacity,
 220             len_base_dir,
 221             "/",
 222             1);
 223
 224         offset_file_name++;
 225     }
 226
 227     while(true) /* try until success */
 228     {
 229         osl_gen_random_name_impl_(&rand_name);
 230
 231         rtl_uStringbuffer_insert(
 232             &tmp_file_path,
 233             &capacity,
 234             offset_file_name,
 235             rtl_uString_getStr(rand_name),
 236             rtl_uString_getLength(rand_name));
 237
 238         osl_error = osl_getFileURLFromSystemPath(
 239             tmp_file_path, &tmp_file_url);
 240
 241         if (osl_error == osl_File_E_None)
 242         {
 243             osl_error = openFile(
 244                 tmp_file_url,
 245                 file_handle,
 246                 osl_File_OpenFlag_Read |
 247                 osl_File_OpenFlag_Write |
 248                 osl_File_OpenFlag_Create,
 249                 S_IRUSR | S_IWUSR);
 250         }
 251
 252         /* in case of error osl_File_E_EXIST we simply try again else we give up */
 253
 254         if (osl_error != osl_File_E_EXIST)
 255         {
 256             rtl_uString_release(rand_name);
 257
 258             if (tmp_file_url)
 259                 rtl_uString_release(tmp_file_url);
 260
 261             break;
 262         }
 263     } /* while(1) */
 264
 265     if (osl_error == osl_File_E_None)
 266         rtl_uString_assign(ppustr_temp_file_name, tmp_file_path);
 267
 268     rtl_uString_release(tmp_file_path);
 269
 270     return osl_error;
 271 }
 272
 273 oslFileError SAL_CALL osl_createTempFile(
 274     rtl_uString*   pustrDirectoryURL,
 275     oslFileHandle* pHandle,
 276     rtl_uString**  ppustrTempFileURL)
 277 {
 278     rtl_uString*  base_directory     = nullptr;
 279     oslFileHandle temp_file_handle = nullptr;
 280     bool      b_delete_on_close;
 281     oslFileError  osl_error;
 282
 283     osl_error = osl_setup_createTempFile_impl_(
 284         pustrDirectoryURL,
 285         pHandle,
 286         ppustrTempFileURL,
 287         &base_directory,
 288         &b_delete_on_close);
 289
 290     if (osl_error != osl_File_E_None)
 291         return osl_error;
 292
 293     rtl_uString*  temp_file_name = nullptr;
 294     osl_error = osl_create_temp_file_impl_(
 295         base_directory, &temp_file_handle, &temp_file_name);
 296
 297     rtl_uString* temp_file_url = nullptr;
 298     if (osl_error == osl_File_E_None)
 299     {
 300         osl_error = osl_getFileURLFromSystemPath(temp_file_name, &temp_file_url);
 301         rtl_uString_release(temp_file_name);
 302     }
 303
 304     if (osl_error == osl_File_E_None)
 305     {
 306         if (b_delete_on_close)
 307         {
 308             osl_error = osl_removeFile(temp_file_url);
 309
 310             if (osl_error == osl_File_E_None)
 311             {
 312                 *pHandle = temp_file_handle;
 313                 temp_file_handle = nullptr;
 314             }
 315         }
 316         else
 317         {
 318             if (pHandle)
 319             {
 320                 *pHandle = temp_file_handle;
 321                 temp_file_handle = nullptr;
 322             }
 323
 324             rtl_uString_assign(ppustrTempFileURL, temp_file_url);
 325         }
 326
 327         rtl_uString_release(temp_file_url);
 328     }
 329
 330     if (temp_file_handle)
 331         osl_closeFile(temp_file_handle);
 332
 333     rtl_uString_release(base_directory);
 334
 335     return osl_error;
 336 }
 337
 338 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */