add part of class streamview

2026-07-14 03:46:15 +08:00 · 2022-06-14 19:41:12 +03:00
parent e049cff2ed
commit e25a2b267d
8 changed files with 513 additions and 16 deletions
--- a/Common/cppcf/streamview.cpp
+++ b/Common/cppcf/streamview.cpp
@ -0,0 +1,138 @@
+#include "streamview.h"
+#include "cfexception.h"
+#include <cmath>
+
+using namespace CFCPP;
+
+StreamView::StreamView(const std::vector<Sector> &sectorChain, int sectorSize, const Stream &stream)
+    : sectorSize(sectorSize), sectorChain(sectorChain), stream(stream)
+{
+    //    if (sectorChain == null)
+    //        throw new CFException("Sector Chain cannot be null");
+
+    if (sectorSize <= 0)
+        throw new CFException("Sector size must be greater than zero");
+}
+
+StreamView::StreamView(const std::vector<Sector> &sectorChain, int sectorSize, std::streamsize length,
+                       std::queue<Sector> &availableSectors, const Stream &stream, bool isFatStream) :
+    StreamView(sectorChain, sectorSize, stream)
+{
+    this->isFatStream = isFatStream;
+    adjustLength(length, availableSectors);
+
+}
+
+std::ostream &StreamView::Write(const char *buffer, std::streamsize offset, std::streamsize count)
+{
+    int byteWritten = 0;
+    int roundByteWritten = 0;
+
+    // Assure length
+    if ((position + count) > length)
+        adjustLength((position + count));
+
+    if (sectorChain.empty() == false)
+    {
+        // First sector
+        int secOffset = (int)(position / (std::streamsize)sectorSize);
+        int secShift = (int)(position % sectorSize);
+
+        roundByteWritten = (int)std::min(sectorSize - (position % (std::streamsize)sectorSize), count);
+
+        if (secOffset < (int)sectorChain.size())
+        {
+            char* dst = reinterpret_cast<char*>(sectorChain[secOffset].GetData().data());
+            std::copy(buffer+offset, buffer+offset+roundByteWritten, dst + secShift);
+
+            sectorChain[secOffset].dirtyFlag = true;
+        }
+
+        byteWritten += roundByteWritten;
+        offset += roundByteWritten;
+        secOffset++;
+
+        // Central sectors
+        while (byteWritten < (count - sectorSize))
+        {
+            roundByteWritten = sectorSize;
+            char* dst = reinterpret_cast<char*>(sectorChain[secOffset].GetData().data());
+            std::copy(buffer+offset, buffer+offset+roundByteWritten, dst);
+
+            sectorChain[secOffset].dirtyFlag = true;
+
+            byteWritten += roundByteWritten;
+            offset += roundByteWritten;
+            secOffset++;
+        }
+
+        // Last sector
+        roundByteWritten = count - byteWritten;
+
+        if (roundByteWritten != 0)
+        {
+
+            char* dst = reinterpret_cast<char*>(sectorChain[secOffset].GetData().data());
+            std::copy(buffer+offset, buffer+offset+roundByteWritten, dst);
+
+            sectorChain[secOffset].dirtyFlag = true;
+
+            offset += roundByteWritten;
+            byteWritten += roundByteWritten;
+        }
+
+        position += count;
+
+    }
+}
+
+int StreamView::ReadInt32()
+{
+    std::iostream::read(reinterpret_cast<char*>(buf), 4);
+    return ((buf & 0xFF) << 24) | ((buf & 0x00FF) << 16) | ((buf & 0x0000FF) << 8) | (buf & 0x000000FF);
+}
+
+void StreamView::adjustLength(std::streamsize value)
+{
+    std::queue<Sector> q;
+    adjustLength(value, q);
+}
+
+void StreamView::adjustLength(std::streamsize value, std::queue<Sector> &availableSectors)
+{
+    this->length = value;
+
+    std::streamsize delta = value - ((std::streamsize)this->sectorChain.size() * (std::streamsize)sectorSize);
+
+    if (delta > 0)
+    {
+        // enlargment required
+
+        int nSec = (int)std::ceil(((double)delta / sectorSize));
+
+        while (nSec > 0)
+        {
+            NSCommon::nullable<Sector> t;
+
+            if (availableSectors.empty() || availableSectors.size() == 0)
+            {
+                t = new Sector(sectorSize, stream);
+
+                if (sectorSize == Sector::MINISECTOR_SIZE)
+                    t->type = SectorType::Mini;
+            }
+            else
+            {
+                t = availableSectors.front();
+                availableSectors.pop();
+            }
+
+            if (isFatStream)
+            {
+                t->InitFATData();
+            }
+            sectorChain.push_back(std::move(t.get()));
+            nSec--;
+        }
+    }
+}