X-Git-Url: https://git.saurik.com/apt.git/blobdiff_plain/a7c835af20feeb470238ead3bda36af978c2600f..aac2e51078714d5130861035e9b3b5d4d6b84471:/apt-pkg/tagfile.cc

diff --git a/apt-pkg/tagfile.cc b/apt-pkg/tagfile.cc
index fdeb09329..79ff18de4 100644
--- a/apt-pkg/tagfile.cc
+++ b/apt-pkg/tagfile.cc
@@ -1,6 +1,6 @@
 // -*- mode: cpp; mode: fold -*-
 // Description								/*{{{*/
-// $Id: tagfile.cc,v 1.28 2001/03/13 06:51:46 jgg Exp $
+// $Id: tagfile.cc,v 1.37.2.2 2003/12/31 16:02:30 mdz Exp $
 /* ######################################################################
 
    Fast scanner for RFC-822 type header information
@@ -23,28 +23,32 @@
     
 #include <string>
 #include <stdio.h>
+#include <ctype.h>
 									/*}}}*/
 
+using std::string;
+
 // TagFile::pkgTagFile - Constructor					/*{{{*/
 // ---------------------------------------------------------------------
 /* */
-pkgTagFile::pkgTagFile(FileFd *pFd,unsigned long Size) : Fd(*pFd), Size(Size)
+pkgTagFile::pkgTagFile(FileFd *pFd,unsigned long Size) :
+     Fd(*pFd),
+     Size(Size)
 {
-   if (Fd.IsOpen() == false)
+   if (Fd.IsOpen() == false || Fd.Size() == 0)
    {
       Buffer = 0;
       Start = End = Buffer = 0;
-      Left = 0;
       iOffset = 0;
+      Map = NULL;
       return;
    }
    
-   Buffer = new char[Size];
-   Start = End = Buffer;
-   Left = Fd.Size();
-   TotalSize = Fd.Size();
+   Map = new MMap (Fd, MMap::Public | MMap::ReadOnly);
+   Buffer = (char *) Map->Data ();
+   Start = Buffer;
+   End = Buffer + Map->Size ();
    iOffset = 0;
-   Fill();
 }
 									/*}}}*/
 // TagFile::~pkgTagFile - Destructor					/*{{{*/
@@ -52,7 +56,7 @@ pkgTagFile::pkgTagFile(FileFd *pFd,unsigned long Size) : Fd(*pFd), Size(Size)
 /* */
 pkgTagFile::~pkgTagFile()
 {
-   delete [] Buffer;
+   delete Map;
 }
 									/*}}}*/
 // TagFile::Step - Advance to the next section				/*{{{*/
@@ -60,69 +64,18 @@ pkgTagFile::~pkgTagFile()
 /* If the Section Scanner fails we refill the buffer and try again. */
 bool pkgTagFile::Step(pkgTagSection &Tag)
 {
+   if (Start == End)
+      return false;
+
    if (Tag.Scan(Start,End - Start) == false)
    {
-      if (Fill() == false)
-	 return false;
-      
-      if (Tag.Scan(Start,End - Start) == false)
-	 return _error->Error(_("Unable to parse package file %s (1)"),Fd.Name().c_str());
-   }   
+      return _error->Error(_("Unable to parse package file %s (1)"),
+	      Fd.Name().c_str());
+   }
    Start += Tag.size();
    iOffset += Tag.size();
 
    Tag.Trim();
-   
-   return true;
-}
-									/*}}}*/
-// TagFile::Fill - Top up the buffer					/*{{{*/
-// ---------------------------------------------------------------------
-/* This takes the bit at the end of the buffer and puts it at the start
-   then fills the rest from the file */
-bool pkgTagFile::Fill()
-{
-   unsigned long EndSize = End - Start;
-   
-   memmove(Buffer,Start,EndSize);
-   Start = Buffer;
-   End = Buffer + EndSize;
-   
-   if (Left == 0)
-   {
-      if (EndSize <= 3)
-	 return false;
-      if (Size - (End - Buffer) < 4)
-	 return true;
-      
-      // Append a double new line if one does not exist
-      unsigned int LineCount = 0;
-      for (const char *E = End - 1; E - End < 6 && (*E == '\n' || *E == '\r'); E--)
-	 if (*E == '\n')
-	    LineCount++;
-      for (; LineCount < 2; LineCount++)
-	 *End++ = '\n';
-      
-      return true;
-   }
-   
-   // See if only a bit of the file is left
-   if (Left < Size - (End - Buffer))
-   {
-      if (Fd.Read(End,Left) == false)
-	 return false;
-      
-      End += Left;
-      Left = 0;
-   }
-   else
-   {
-      if (Fd.Read(End,Size - (End - Buffer)) == false)
-	 return false;
-      
-      Left -= Size - (End - Buffer);
-      End = Buffer + Size;
-   }   
    return true;
 }
 									/*}}}*/
@@ -143,22 +96,10 @@ bool pkgTagFile::Jump(pkgTagSection &Tag,unsigned long Offset)
 
    // Reposition and reload..
    iOffset = Offset;
-   Left = TotalSize - Offset;
-   if (Fd.Seek(Offset) == false)
-      return false;
-   End = Start = Buffer;
-   
-   if (Fill() == false)
-      return false;
-
-   if (Tag.Scan(Start,End - Start) == true)
-      return true;
+   Start = Buffer + iOffset;
    
-   // This appends a double new line (for the real eof handling)
-   if (Fill() == false)
-      return false;
-   
-   if (Tag.Scan(Start,End - Start) == false)
+   // Start != End is a special case to not fail on empty TagFiles
+   if (Start != End && Tag.Scan(Start,End - Start) == false)
       return _error->Error(_("Unable to parse package file %s (2)"),Fd.Name().c_str());
    
    return true;
@@ -183,11 +124,11 @@ bool pkgTagSection::Scan(const char *Start,unsigned long MaxLength)
    Stop = Section = Start;
    memset(AlphaIndexes,0,sizeof(AlphaIndexes));
 
-   if (Stop == 0)
+   if (Stop == 0 || MaxLength == 0)
       return false;
    
    TagCount = 0;
-   while (TagCount < sizeof(Indexes)/sizeof(Indexes[0]) && Stop < End)
+   while (TagCount+1 < sizeof(Indexes)/sizeof(Indexes[0]) && Stop < End)
    {
       // Start a new index and add it to the hash
       if (isspace(Stop[0]) == 0)
@@ -201,19 +142,25 @@ bool pkgTagSection::Scan(const char *Start,unsigned long MaxLength)
       if (Stop == 0)
 	 return false;
       
-      for (; Stop[1] == '\r' && Stop+1 < End; Stop++);
+      for (; Stop+1 < End && Stop[1] == '\r'; Stop++);
 
       // Double newline marks the end of the record
       if (Stop+1 < End && Stop[1] == '\n')
       {
 	 Indexes[TagCount] = Stop - Section;
-	 for (; (Stop[0] == '\n' || Stop[0] == '\r') && Stop < End; Stop++);
+	 for (; Stop < End && (Stop[0] == '\n' || Stop[0] == '\r'); Stop++);
 	 return true;
       }
       
       Stop++;
    }
 
+   if ((Stop+1 >= End) && (End[-1] == '\n' || End[-1] == '\r'))
+   {
+       Indexes[TagCount] = (End - 1) - Section;
+       return true;
+   }
+
    return false;
 }
 									/*}}}*/