Recognize and handle raw data files in the data tool

[libs/datafile.git] / source / rawdata.cpp

diff --git a/source/rawdata.cpp b/source/rawdata.cpp
index 7a90c9df3870c835a134494975a3b1e5343073d5..de4d7c22bb6e9d1a195174451a08e4817f1b2c75 100644 (file)
--- a/source/rawdata.cpp
+++ b/source/rawdata.cpp
@@ -1,3 +1,4 @@
+#include <cstring>
 #include <stdexcept>
 #include <msp/io/zlibcompressed.h>
 #include "collection.h"
@@ -9,6 +10,8 @@ using namespace std;
 namespace Msp {
 namespace DataFile {
 
+const char RawData::signature[4] = { 'M', 'D', 'R', 1 };
+
 RawData::~RawData()
 {
        delete owned_data;
@@ -17,6 +20,11 @@ RawData::~RawData()
                delete in;
 }
 
+bool RawData::detect_signature(const std::string &sig)
+{
+       return !sig.compare(0, string::npos, signature, sizeof(signature));
+}
+
 void RawData::open_file(Collection &coll, const string &fn)
 {
        if(in)
@@ -40,7 +48,7 @@ void RawData::open_io(IO::Base &i, const string &fn)
        unsigned len = i.read(header, sizeof(header));
        if(len!=sizeof(header))
                throw data_error(fn, 0, "Missing header");
-       if(header[0]!='M' || header[1]!='D' || header[2]!='R' || header[3]!=1)
+       if(memcmp(header, signature, sizeof(signature)))
                throw data_error(fn, 0, "Bad header");
 
        size = 0;
@@ -88,5 +96,30 @@ void RawData::load_into(void *buffer)
        in = nullptr;
 }
 
+void RawData::write_io(IO::Base &io, bool compress)
+{
+       if(!data)
+               throw logic_error("no data");
+
+       io.write(signature, sizeof(signature));
+
+       for(unsigned i=56; i<64; i-=8)
+               io.put((size>>i)&0xFF);
+
+       uint16_t flags = 0;
+       if(compress)
+               flags |= COMPRESSED;
+       io.put((flags>>8)&0xFF);
+       io.put(flags&0xFF);
+
+       if(compress)
+       {
+               IO::ZlibCompressed z(io, IO::M_WRITE);
+               z.write(data, size);
+       }
+       else
+               io.write(data, size);
+}
+
 } // namespace DataFile
 } // namespace Msp