X-Git-Url: https://git.cworth.org/git?a=blobdiff_plain;f=trace_snappyfile.cpp;h=4dbe42dc364264a8db0e717a1af17681b9af271e;hb=447f4a55a01e82b0265f44212b8d439fa83750d7;hp=cea4e6866c45fb14d529df6652bd8755c4b60c53;hpb=49c4feee9e955d681dd407478de5c7daedf7ba34;p=apitrace

diff --git a/trace_snappyfile.cpp b/trace_snappyfile.cpp
index cea4e68..4dbe42d 100644
--- a/trace_snappyfile.cpp
+++ b/trace_snappyfile.cpp
@@ -93,13 +93,17 @@ bool SnappyFile::rawOpen(const std::string &filename, File::Mode mode)
 
     //read in the initial buffer if we're reading
     if (m_stream.is_open() && mode == File::Read) {
+        m_stream.seekg(0, std::ios::end);
+        m_endPos = m_stream.tellg();
+        m_stream.seekg(0, std::ios::beg);
+
         // read the snappy file identifier
         unsigned char byte1, byte2;
         m_stream >> byte1;
         m_stream >> byte2;
         assert(byte1 == SNAPPY_BYTE1 && byte2 == SNAPPY_BYTE2);
 
-        flushCache();
+        flushReadCache();
     } else if (m_stream.is_open() && mode == File::Write) {
         // write the snappy file identifier
         m_stream << SNAPPY_BYTE1;
@@ -116,7 +120,7 @@ bool SnappyFile::rawWrite(const void *buffer, size_t length)
     } else if (freeCacheSize() == length) {
         memcpy(m_cachePtr, buffer, length);
         m_cachePtr += length;
-        flushCache();
+        flushWriteCache();
     } else {
         int sizeToWrite = length;
 
@@ -126,7 +130,7 @@ bool SnappyFile::rawWrite(const void *buffer, size_t length)
             memcpy(m_cachePtr, (const char*)buffer + offset, endSize);
             sizeToWrite -= endSize;
             m_cachePtr += endSize;
-            flushCache();
+            flushWriteCache();
         }
         if (sizeToWrite) {
             int offset = length - sizeToWrite;
@@ -156,10 +160,12 @@ bool SnappyFile::rawRead(void *buffer, size_t length)
             memcpy((char*)buffer + offset, m_cachePtr, chunkSize);
             m_cachePtr += chunkSize;
             sizeToRead -= chunkSize;
-            if (sizeToRead > 0)
-                flushCache();
-            if (!m_cacheSize)
+            if (sizeToRead > 0) {
+                flushReadCache();
+            }
+            if (!m_cacheSize) {
                 break;
+            }
         }
     }
 
@@ -176,7 +182,9 @@ int SnappyFile::rawGetc()
 
 void SnappyFile::rawClose()
 {
-    flushCache();
+    if (m_mode == File::Write) {
+        flushWriteCache();
+    }
     m_stream.close();
     delete [] m_cache;
     m_cache = NULL;
@@ -185,42 +193,46 @@ void SnappyFile::rawClose()
 
 void SnappyFile::rawFlush()
 {
-    flushCache();
+    assert(m_mode == File::Write);
+    flushWriteCache();
     m_stream.flush();
 }
 
-void SnappyFile::flushCache()
+void SnappyFile::flushWriteCache()
 {
-    if (m_mode == File::Write) {
-        size_t inputLength = usedCacheSize();
+    size_t inputLength = usedCacheSize();
 
-        if (inputLength) {
-            size_t compressedLength;
+    if (inputLength) {
+        size_t compressedLength;
 
-            ::snappy::RawCompress(m_cache, inputLength,
-                                  m_compressedCache, &compressedLength);
+        ::snappy::RawCompress(m_cache, inputLength,
+                              m_compressedCache, &compressedLength);
 
-            writeCompressedLength(compressedLength);
-            m_stream.write(m_compressedCache, compressedLength);
-            m_cachePtr = m_cache;
-        }
-        assert(m_cachePtr == m_cache);
-    } else if (m_mode == File::Read) {
-        //assert(m_cachePtr == m_cache + m_cacheSize);
-        m_currentOffset.chunk = m_stream.tellg();
-        size_t compressedLength;
-        compressedLength = readCompressedLength();
+        writeCompressedLength(compressedLength);
+        m_stream.write(m_compressedCache, compressedLength);
+        m_cachePtr = m_cache;
+    }
+    assert(m_cachePtr == m_cache);
+}
 
-        if (compressedLength) {
-            m_stream.read((char*)m_compressedCache, compressedLength);
-            ::snappy::GetUncompressedLength(m_compressedCache, compressedLength,
-                                            &m_cacheSize);
-            createCache(m_cacheSize);
+void SnappyFile::flushReadCache(size_t skipLength)
+{
+    //assert(m_cachePtr == m_cache + m_cacheSize);
+    m_currentOffset.chunk = m_stream.tellg();
+    size_t compressedLength;
+    compressedLength = readCompressedLength();
+
+    if (compressedLength) {
+        m_stream.read((char*)m_compressedCache, compressedLength);
+        ::snappy::GetUncompressedLength(m_compressedCache, compressedLength,
+                                        &m_cacheSize);
+        createCache(m_cacheSize);
+        if (skipLength < m_cacheSize) {
             ::snappy::RawUncompress(m_compressedCache, compressedLength,
                                     m_cache);
-        } else {
-            createCache(0);
         }
+    } else {
+        createCache(0);
     }
 }
 
@@ -287,14 +299,14 @@ void SnappyFile::setCurrentOffset(const File::Offset &offset)
     // seek to the start of a chunk
     m_stream.seekg(offset.chunk, std::ios::beg);
     // load the chunk
-    flushCache();
+    flushReadCache();
     assert(m_cacheSize >= offset.offsetInChunk);
     // seek within our cache to the correct location within the chunk
     m_cachePtr = m_cache + offset.offsetInChunk;
 
 }
 
-bool SnappyFile::rawSkip(unsigned length)
+bool SnappyFile::rawSkip(size_t length)
 {
     if (endOfData()) {
         return false;
@@ -308,12 +320,19 @@ bool SnappyFile::rawSkip(unsigned length)
             size_t chunkSize = std::min(freeCacheSize(), sizeToRead);
             m_cachePtr += chunkSize;
             sizeToRead -= chunkSize;
-            if (sizeToRead > 0)
-                flushCache();
-            if (!m_cacheSize)
+            if (sizeToRead > 0) {
+                flushReadCache(sizeToRead);
+            }
+            if (!m_cacheSize) {
                 break;
+            }
         }
     }
 
     return true;
 }
+
+int SnappyFile::rawPercentRead()
+{
+    return 100 * (double(m_stream.tellg()) / double(m_endPos));
+}