xpcom/ds/nsManifestLineReader.h

   1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* ***** BEGIN LICENSE BLOCK *****
   3  * Version: MPL 1.1/GPL 2.0/LGPL 2.1
   4  *
   5  * The contents of this file are subject to the Mozilla Public License Version
   6  * 1.1 (the "License"); you may not use this file except in compliance with
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   8  * http://www.mozilla.org/MPL/
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  10  * Software distributed under the License is distributed on an "AS IS" basis,
  11  * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
  12  * for the specific language governing rights and limitations under the
  13  * License.
  14  *
  15  * The Original Code is mozilla.org code.
  16  *
  17  * The Initial Developer of the Original Code is
  18  * Netscape Communications Corporation.
  19  * Portions created by the Initial Developer are Copyright (C) 1998
  20  * the Initial Developer. All Rights Reserved.
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  22  * Contributor(s):
  23  *
  24  * Alternatively, the contents of this file may be used under the terms of
  25  * either of the GNU General Public License Version 2 or later (the "GPL"),
  26  * or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
  27  * in which case the provisions of the GPL or the LGPL are applicable instead
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  36  * ***** END LICENSE BLOCK ***** */
  37
  38 #ifndef nsManifestLineReader_h__
  39 #define nsManifestLineReader_h__
  40
  41 #include "nspr.h"
  42 #include "nsDebug.h"
  43
  44 class nsManifestLineReader
  45 {
  46 public:
  47     nsManifestLineReader() : mBase(nsnull) {}
  48     ~nsManifestLineReader() {}
  49
  50     void Init(char* base, PRUint32 flen)
  51     {
  52         mBase = mCur = mNext = base;
  53         mLength = 0;
  54         mLimit = base + flen;
  55     }
  56
  57     PRBool NextLine()
  58     {
  59         if(mNext >= mLimit)
  60             return PR_FALSE;
  61
  62         mCur = mNext;
  63         mLength = 0;
  64
  65         while(mNext < mLimit)
  66         {
  67             if(IsEOL(*mNext))
  68             {
  69                 *mNext = '\0';
  70                 for(++mNext; mNext < mLimit; ++mNext)
  71                     if(!IsEOL(*mNext))
  72                         break;
  73                 return PR_TRUE;
  74             }
  75             ++mNext;
  76             ++mLength;
  77         }
  78         return PR_FALSE;
  79     }
  80
  81     int ParseLine(char** chunks, int* lengths, int maxChunks)
  82     {
  83         NS_ASSERTION(mCur && maxChunks && chunks, "bad call to ParseLine");
  84         int found = 0;
  85         chunks[found++] = mCur;
  86
  87         if(found < maxChunks)
  88         {
  89             char *lastchunk = mCur;
  90             int *lastlength = lengths;
  91             for(char* cur = mCur; *cur; cur++)
  92             {
  93                 if(*cur == ',')
  94                 {
  95                     *cur = 0;
  96                     // always fill in the previous chunk's length
  97                     *lastlength++ = cur - lastchunk;
  98                     chunks[found++] = lastchunk = cur+1;
  99                     if(found == maxChunks)
 100                         break;
 101                 }
 102             }
 103             // crazy pointer math - calculate the length of the final chunk
 104             *lastlength = (mCur + mLength) - lastchunk;
 105         }
 106         return found;
 107     }
 108
 109     char*       LinePtr() {return mCur;}
 110     PRUint32    LineLength() {return mLength;}
 111
 112     PRBool      IsEOL(char c) {return c == '\n' || c == '\r';}
 113 private:
 114     char*       mCur;
 115     PRUint32    mLength;
 116     char*       mNext;
 117     char*       mBase;
 118     char*       mLimit;
 119 };
 120
 121 #endif