support: add (broken) support of C++ standard streams

src/gmio_support/stream_cpp.h

@@ -0,0 +1,121 @@
+/****************************************************************************
+** gmio
+** Copyright Fougue (2 Mar. 2015)
+** contact@fougue.pro
+**
+** This software is a reusable library whose purpose is to provide complete
+** I/O support for various CAD file formats (eg. STL)
+**
+** This software is governed by the CeCILL-B license under French law and
+** abiding by the rules of distribution of free software.  You can  use,
+** modify and/ or redistribute the software under the terms of the CeCILL-B
+** license as circulated by CEA, CNRS and INRIA at the following URL
+** "http://www.cecill.info/licences/Licence_CeCILL-B_V1-en.html".
+****************************************************************************/
+
+/*! \file stream_cpp.h
+ *  Support of standard C++ streams
+ *
+*  \addtogroup gmio_support
+ *  @{
+ */
+
+#ifndef GMIO_SUPPORT_STREAM_CPP_H
+#define GMIO_SUPPORT_STREAM_CPP_H
+
+#include "support_global.h"
+#include "../gmio_core/stream.h"
+
+#include <cstring>
+#include <iostream>
+
+template<typename STREAM>
+gmio_stream_t gmio_stream_cpp(STREAM* s);
+
+//
+// Implementation
+//
+
+template<typename STREAM>
+gmio_bool_t gmio_stream_cpp_at_end(void* cookie)
+{
+    STREAM* s = static_cast<STREAM*>(cookie);
+    return s->eof();
+}
+
+template<typename STREAM>
+int gmio_stream_cpp_error(void* cookie)
+{
+    STREAM* s = static_cast<STREAM*>(cookie);
+    return s->rdstate();
+}
+
+template<typename STREAM>
+size_t gmio_stream_cpp_read(
+        void* cookie, void* ptr, size_t item_size, size_t item_count)
+{
+    STREAM* s = static_cast<STREAM*>(cookie);
+    s->read(static_cast<char*>(ptr), item_size * item_count);
+    return s->gcount() / item_size;
+}
+
+template<typename STREAM>
+size_t gmio_stream_cpp_write(
+        void* cookie, const void* ptr, size_t item_size, size_t item_count)
+{
+    STREAM* s = static_cast<STREAM*>(cookie);
+    s->write(static_cast<const char*>(ptr), item_size * item_count);
+    // TODO: return the number of bytes actually written
+    return item_size * item_count;
+}
+
+template<typename STREAM>
+size_t gmio_stream_cpp_size(void* cookie)
+{
+    STREAM* s = static_cast<STREAM*>(cookie);
+    std::streampos pos = s->tellg();
+    s->seekg(0, std::ios_base::beg);
+    std::streampos begin_pos = s->tellg();
+    s->seekg(0, std::ios_base::end);
+    std::streampos end_pos = s->tellg();
+    s->seekg(pos, std::ios_base::beg);
+    return end_pos - begin_pos;
+}
+
+template<typename STREAM>
+int gmio_stream_cpp_get_pos(void* cookie, gmio_stream_pos_t* pos)
+{
+    STREAM* s = static_cast<STREAM*>(cookie);
+    std::streampos spos = s->tellg();
+    std::memcpy(&pos->cookie[0], &spos, sizeof(std::streampos));
+    return 0;
+}
+
+template<typename STREAM>
+static int gmio_stream_cpp_set_pos(void* cookie, const gmio_stream_pos_t* pos)
+{
+    STREAM* s = static_cast<STREAM*>(cookie);
+    std::streampos spos;
+    std::memcpy(&spos, &pos->cookie[0], sizeof(std::streampos));
+    s->seekg(spos);
+    s->seekp(spos);
+    return 0; // TODO: return error code
+}
+
+template<typename STREAM>
+gmio_stream_t gmio_stream_cpp(STREAM* s)
+{
+    gmio_stream_t stream = gmio_stream_null();
+    stream.cookie = s;
+    stream.func_at_end = gmio_stream_cpp_at_end<STREAM>;
+    stream.func_error = gmio_stream_cpp_error<STREAM>;
+    stream.func_read = gmio_stream_cpp_read<STREAM>;
+    stream.func_write = gmio_stream_cpp_write<STREAM>;
+    stream.func_size = gmio_stream_cpp_size<STREAM>;
+    stream.func_get_pos = gmio_stream_cpp_get_pos<STREAM>;
+    stream.func_set_pos = gmio_stream_cpp_set_pos<STREAM>;
+    return stream;
+}
+
+#endif /* GMIO_SUPPORT_STREAM_CPP_H */
+/*! @} */

tests/fake_support/main.cpp

@@ -6,6 +6,9 @@
 
 #include <Handle_StlMesh_Mesh.hxx>
 
+#include "../../src/gmio_support/stream_cpp.h"
+#include <fstream>
+
 int main()
 {
     // OpenCascade
@@ -16,5 +19,9 @@ int main()
     QFile file;
     gmio_stream_qiodevice(&file);
 
+    // C++
+    //std::ifstream s("test.txt");
+    //gmio_stream_t stream = gmio_stream_cpp(&s);
+
     return 0;
 }