gfx/src/psshared/nsCUPSShim.cpp

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   3 /* ***** BEGIN LICENSE BLOCK *****
   4  * Version: MPL 1.1/GPL 2.0/LGPL 2.1
   5  *
   6  * The contents of this file are subject to the Mozilla Public License Version
   7  * 1.1 (the "License"); you may not use this file except in compliance with
   8  * the License. You may obtain a copy of the License at
   9  * http://www.mozilla.org/MPL/
  10  *
  11  * Software distributed under the License is distributed on an "AS IS" basis,
  12  * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
  13  * for the specific language governing rights and limitations under the
  14  * License.
  15  *
  16  * The Original Code is the Mozilla PostScript driver printer list component.
  17  *
  18  * The Initial Developer of the Original Code is
  19  * Kenneth Herron <kherron+mozilla@fmailbox.com>
  20  * Portions created by the Initial Developer are Copyright (C) 2004
  21  * the Initial Developer. All Rights Reserved.
  22  *
  23  * Contributor(s):
  24  *
  25  * Alternatively, the contents of this file may be used under the terms of
  26  * either the GNU General Public License Version 2 or later (the "GPL"), or
  27  * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
  28  * in which case the provisions of the GPL or the LGPL are applicable instead
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  34  * the provisions above, a recipient may use your version of this file under
  35  * the terms of any one of the MPL, the GPL or the LGPL.
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  37  * ***** END LICENSE BLOCK ***** */
  38
  39 #include "nsDebug.h"
  40 #include "nsString.h"
  41 #include "nsCUPSShim.h"
  42 #include "prlink.h"
  43
  44
  45 // List of symbols to find in libcups. Must match symAddr[] defined in Init().
  46 // Making this an array of arrays instead of pointers allows storing the
  47 // whole thing in read-only memory.
  48 static const char gSymName[][sizeof("cupsPrintFile")] = {
  49     { "cupsAddOption" },
  50     { "cupsFreeDests" },
  51     { "cupsGetDest" },
  52     { "cupsGetDests" },
  53     { "cupsPrintFile" },
  54     { "cupsTempFd" },
  55 };
  56 static const int gSymNameCt = sizeof(gSymName) / sizeof(gSymName[0]);
  57
  58
  59 PRBool
  60 nsCUPSShim::Init()
  61 {
  62     mCupsLib = PR_LoadLibrary("libcups.so.2");
  63     if (!mCupsLib)
  64         return PR_FALSE;
  65
  66     // List of symbol pointers. Must match gSymName[] defined above.
  67     void **symAddr[] = {
  68         (void **)&mCupsAddOption,
  69         (void **)&mCupsFreeDests,
  70         (void **)&mCupsGetDest,
  71         (void **)&mCupsGetDests,
  72         (void **)&mCupsPrintFile,
  73         (void **)&mCupsTempFd,
  74     };
  75
  76     for (int i = gSymNameCt; i--; ) {
  77         *(symAddr[i]) = PR_FindSymbol(mCupsLib, gSymName[i]);
  78         if (! *(symAddr[i])) {
  79 #ifdef DEBUG
  80             nsCAutoString msg(gSymName[i]);
  81             msg.Append(" not found in CUPS library");
  82             NS_WARNING(msg.get());
  83 #endif
  84             PR_UnloadLibrary(mCupsLib);
  85             mCupsLib = nsnull;
  86             return PR_FALSE;
  87         }
  88     }
  89     return PR_TRUE;
  90 }
  91
  92 nsCUPSShim::~nsCUPSShim()
  93 {
  94     if (mCupsLib)
  95         PR_UnloadLibrary(mCupsLib);
  96 }