add test for apt show

[apt.git] / apt-pkg / tagfile.cc

diff --git a/apt-pkg/tagfile.cc b/apt-pkg/tagfile.cc
index ec86173df5fffb3db66117ebb6167e98086bb69b..bef3c76ba3c92c8c5c98e1342902109880f3bcac 100644 (file)
--- a/apt-pkg/tagfile.cc
+++ b/apt-pkg/tagfile.cc
@@ -30,7 +30,10 @@ using std::string;
 class pkgTagFilePrivate
 {
 public:
-   pkgTagFilePrivate(FileFd *pFd, unsigned long long Size) : Fd(*pFd), Size(Size)
+   pkgTagFilePrivate(FileFd *pFd, unsigned long long Size) : Fd(*pFd), Buffer(NULL),
+                                                            Start(NULL), End(NULL),
+                                                            Done(false), iOffset(0),
+                                                            Size(Size)
    {
    }
    FileFd &Fd;
@@ -47,21 +50,27 @@ public:
 /* */
 pkgTagFile::pkgTagFile(FileFd *pFd,unsigned long long Size)
 {
+   /* The size is increased by 4 because if we start with the Size of the
+      filename we need to try to read 1 char more to see an EOF faster, 1
+      char the end-pointer can be on and maybe 2 newlines need to be added
+      to the end of the file -> 4 extra chars */
+   Size += 4;
    d = new pkgTagFilePrivate(pFd, Size);
 
    if (d->Fd.IsOpen() == false)
-   {
       d->Start = d->End = d->Buffer = 0;
+   else
+      d->Buffer = (char*)malloc(sizeof(char) * Size);
+
+   if (d->Buffer == NULL)
       d->Done = true;
-      d->iOffset = 0;
-      return;
-   }
-   
-   d->Buffer = new char[Size];
+   else
+      d->Done = false;
+
    d->Start = d->End = d->Buffer;
-   d->Done = false;
    d->iOffset = 0;
-   Fill();
+   if (d->Done == false)
+      Fill();
 }
                                                                        /*}}}*/
 // TagFile::~pkgTagFile - Destructor                                   /*{{{*/
@@ -69,11 +78,11 @@ pkgTagFile::pkgTagFile(FileFd *pFd,unsigned long long Size)
 /* */
 pkgTagFile::~pkgTagFile()
 {
-   delete [] d->Buffer;
+   free(d->Buffer);
    delete d;
 }
                                                                        /*}}}*/
-// TagFile::Offset - Return the current offset in the buffer           /*{{{*/
+// TagFile::Offset - Return the current offset in the buffer           /*{{{*/
 unsigned long pkgTagFile::Offset()
 {
    return d->iOffset;
@@ -86,19 +95,22 @@ unsigned long pkgTagFile::Offset()
  */
 bool pkgTagFile::Resize()
 {
-   char *tmp;
-   unsigned long long EndSize = d->End - d->Start;
-
    // fail is the buffer grows too big
    if(d->Size > 1024*1024+1)
       return false;
 
+   return Resize(d->Size * 2);
+}
+bool pkgTagFile::Resize(unsigned long long const newSize)
+{
+   unsigned long long const EndSize = d->End - d->Start;
+
    // get new buffer and use it
-   tmp = new char[2*d->Size];
-   memcpy(tmp, d->Buffer, d->Size);
-   d->Size = d->Size*2;
-   delete [] d->Buffer;
-   d->Buffer = tmp;
+   char* newBuffer = (char*)realloc(d->Buffer, sizeof(char) * newSize);
+   if (newBuffer == NULL)
+      return false;
+   d->Buffer = newBuffer;
+   d->Size = newSize;
 
    // update the start/end pointers to the new buffer
    d->Start = d->Buffer;
@@ -149,9 +161,10 @@ bool pkgTagFile::Fill()
    if (d->Done == false)
    {
       // See if only a bit of the file is left
-      if (d->Fd.Read(d->End, d->Size - (d->End - d->Buffer),&Actual) == false)
+      unsigned long long const dataSize = d->Size - ((d->End - d->Buffer) + 1);
+      if (d->Fd.Read(d->End, dataSize, &Actual) == false)
         return false;
-      if (Actual != d->Size - (d->End - d->Buffer))
+      if (Actual != dataSize)
         d->Done = true;
       d->End += Actual;
    }
@@ -168,8 +181,13 @@ bool pkgTagFile::Fill()
       for (const char *E = d->End - 1; E - d->End < 6 && (*E == '\n' || *E == '\r'); E--)
         if (*E == '\n')
            LineCount++;
-      for (; LineCount < 2; LineCount++)
-        *d->End++ = '\n';
+      if (LineCount < 2)
+      {
+        if ((unsigned)(d->End - d->Buffer) >= d->Size)
+           Resize(d->Size + 3);
+        for (; LineCount < 2; LineCount++)
+           *d->End++ = '\n';
+      }
       
       return true;
    }
@@ -215,6 +233,16 @@ bool pkgTagFile::Jump(pkgTagSection &Tag,unsigned long long Offset)
    return true;
 }
                                                                        /*}}}*/
+// pkgTagSection::pkgTagSection - Constructor                          /*{{{*/
+// ---------------------------------------------------------------------
+/* */
+pkgTagSection::pkgTagSection()
+   : Section(0), TagCount(0), d(NULL), Stop(0)
+{
+   memset(&Indexes, 0, sizeof(Indexes));
+   memset(&AlphaIndexes, 0, sizeof(AlphaIndexes));
+}
+                                                                       /*}}}*/
 // TagSection::Scan - Scan for the end of the header information       /*{{{*/
 // ---------------------------------------------------------------------
 /* This looks for the first double new line in the data stream.
@@ -231,7 +259,12 @@ bool pkgTagSection::Scan(const char *Start,unsigned long MaxLength)
    TagCount = 0;
    while (TagCount+1 < sizeof(Indexes)/sizeof(Indexes[0]) && Stop < End)
    {
-       TrimRecord(true,End);
+      TrimRecord(true,End);
+
+      // this can happen when TrimRecord trims away the entire Record
+      // (e.g. because it just contains comments)
+      if(Stop == End)
+         return true;
 
       // Start a new index and add it to the hash
       if (isspace(Stop[0]) == 0)
@@ -245,7 +278,9 @@ bool pkgTagSection::Scan(const char *Start,unsigned long MaxLength)
       if (Stop == 0)
         return false;
 
-      for (; Stop+1 < End && Stop[1] == '\r'; Stop++);
+      for (; Stop+1 < End && Stop[1] == '\r'; Stop++)
+         /* nothing */
+         ;
 
       // Double newline marks the end of the record
       if (Stop+1 < End && Stop[1] == '\n')
@@ -279,10 +314,17 @@ void pkgTagSection::Trim()
    for (; Stop > Section + 2 && (Stop[-2] == '\n' || Stop[-2] == '\r'); Stop--);
 }
                                                                        /*}}}*/
+// TagSection::Exists - return True if a tag exists                    /*{{{*/
+bool pkgTagSection::Exists(const char* const Tag)
+{
+   unsigned int tmp;
+   return Find(Tag, tmp);
+}
+                                                                       /*}}}*/
 // TagSection::Find - Locate a tag                                     /*{{{*/
 // ---------------------------------------------------------------------
 /* This searches the section for a tag that matches the given string. */
-bool pkgTagSection::Find(const char *Tag,unsigned &Pos) const
+bool pkgTagSection::Find(const char *Tag,unsigned int &Pos) const
 {
    unsigned int Length = strlen(Tag);
    unsigned int I = AlphaIndexes[AlphaHash(Tag)];