MxFile and implementations 100% match

* Add MxFile and it's implementations, MxSystemFile and MxMemoryFile.
  The names are chosen by me, we don't know their original naming.

* These expose a Read/Write/Seek/Tell interface for reading and writing
  data, either from a file on disk or memory buffer.

* 100% match all functions.

CMakeLists.txt

@@ -118,6 +118,7 @@ add_library(lego1 SHARED
   LEGO1/mxentity.cpp
   LEGO1/mxeventmanager.cpp
   LEGO1/mxeventpresenter.cpp
+  LEGO1/mxfile.cpp
   LEGO1/mxflcpresenter.cpp
   LEGO1/mxioinfo.cpp
   LEGO1/mxloopingflcpresenter.cpp

LEGO1/mxfile.cpp

@@ -0,0 +1,142 @@
+
+#include "mxfile.h"
+
+#include <cstdio>
+#include <string>
+
+// OFFSET: LEGO1 0x10045ae0
+MxBool MxFile::IsWriteMode()
+{
+  return m_mode == MXFILE_MODE_WRITE;
+}
+
+// OFFSET: LEGO1 0x10045af0
+MxBool MxFile::IsReadMode()
+{
+  return m_mode == MXFILE_MODE_READ;
+}
+
+// OFFSET: LEGO1 0x100991c0
+MxSystemFile::MxSystemFile()
+  : MxFile()
+{
+  m_hFile = NULL;
+}
+
+// OFFSET: LEGO1 0x10099250
+MxSystemFile::~MxSystemFile()
+{
+  if (m_hFile != NULL)
+    fclose(m_hFile);
+}
+
+// OFFSET: LEGO1 0x100992c0
+MxResult MxSystemFile::Read(char* buffer, MxU32 size)
+{
+  if (m_hFile == NULL)
+    return FAILURE;
+
+  return (fread(buffer, 1, size, m_hFile) == size) ? SUCCESS : FAILURE;
+}
+
+// OFFSET: LEGO1 0x10099300
+MxResult MxSystemFile::Write(char* buffer, MxU32 size)
+{
+  if (m_hFile == NULL)
+    return FAILURE;
+
+  return (fwrite(buffer, 1, size, m_hFile) == size) ? SUCCESS : FAILURE;
+}
+
+// OFFSET: LEGO1 0x10099340
+MxResult MxSystemFile::Tell(MxU32* offset)
+{
+  if (m_hFile == NULL)
+    return FAILURE;
+
+  int got = ftell(m_hFile);
+  if (got == -1)
+    return FAILURE;
+
+  *offset = got;
+  return SUCCESS;
+}
+
+// OFFSET: LEGO1 0x10099370
+MxResult MxSystemFile::Seek(MxU32 offset)
+{
+  if (m_hFile == NULL)
+    return FAILURE;
+
+  return (fseek(m_hFile, offset, 0) == 0) ? SUCCESS : FAILURE;
+}
+
+// OFFSET: LEGO1 0x100993a0
+MxResult MxSystemFile::Open(const char* filename, OpenFlags mode)
+{
+  char modeString[4];
+
+  if (m_hFile != NULL)
+    fclose(m_hFile);
+  
+  modeString[0] = '\0';
+  if (mode & ReadBit)
+  {
+    m_mode = MXFILE_MODE_READ;
+    strcat(modeString, "r");
+  }
+
+  if (mode & WriteBit)
+  {
+    if (m_mode != MXFILE_MODE_READ)
+      m_mode = MXFILE_MODE_WRITE;
+    strcat(modeString, "w");
+  }
+
+  if ((mode & 4) != 0)
+    strcat(modeString, "b");
+  else
+    strcat(modeString, "t");
+
+  return (m_hFile = fopen(filename, modeString)) ? SUCCESS : FAILURE;
+}
+
+// OFFSET: LEGO1 0x10099080
+MxMemoryFile::MxMemoryFile(char* buffer)
+  : MxFile()
+{
+  m_buffer = buffer;
+  m_offset = 0;
+}
+
+// OFFSET: LEGO1 0x10099160
+MxResult MxMemoryFile::Read(char* buffer, MxU32 size)
+{
+  memcpy(buffer, m_buffer + m_offset, size);
+  m_offset += size;
+  return SUCCESS;
+}
+
+// OFFSET: LEGO1 0x10099190
+MxResult MxMemoryFile::Write(char* buffer, MxU32 size)
+{
+  memcpy(m_buffer + m_offset, buffer, size);
+  m_offset += size;
+  return SUCCESS;
+}
+
+// OFFSET: LEGO1 0x100994a0
+MxResult MxMemoryFile::Tell(MxU32* offset)
+{
+  *offset = m_offset;
+  return SUCCESS;
+}
+
+// OFFSET: LEGO1 0x100994b0
+MxResult MxMemoryFile::Seek(MxU32 offset)
+{
+  m_offset = offset;
+  return SUCCESS;
+}
+
+

LEGO1/mxfile.h

@@ -0,0 +1,70 @@
+#ifndef MXFILE_H
+#define MXFILE_H
+
+#include "decomp.h"
+#include "mxtypes.h"
+
+#include <iosfwd>
+
+#define MXFILE_MODE_READ 1
+#define MXFILE_MODE_WRITE 2
+
+class MxFile
+{
+public:
+  MxFile() : m_mode(0) {}
+  inline virtual ~MxFile() {};
+
+  virtual MxResult Read(char* buffer, MxU32 size) = 0;
+  virtual MxResult Write(char* buffer, MxU32 size) = 0;
+  virtual MxResult Tell(MxU32* offset) = 0;
+  virtual MxResult Seek(MxU32 offset) = 0;
+
+  virtual MxBool IsWriteMode();
+  virtual MxBool IsReadMode();
+
+  enum OpenFlags
+  {
+    ReadBit = 1,
+    WriteBit = 2,
+    BinaryBit = 4,
+  };
+
+protected:
+  MxU8 m_mode;
+};
+
+class MxSystemFile : public MxFile
+{
+public:
+  MxSystemFile();
+  virtual ~MxSystemFile();
+
+  MxResult Read(char* buffer, MxU32 size) override;
+  MxResult Write(char* buffer, MxU32 size) override;
+  MxResult Tell(MxU32* offset) override;
+  MxResult Seek(MxU32 offset) override;
+
+  MxResult Open(const char* filename, OpenFlags mode);
+
+private:
+  FILE *m_hFile;
+};
+
+class MxMemoryFile : public MxFile
+{
+public:
+  MxMemoryFile(char* buffer);
+  ~MxMemoryFile() {}
+
+  MxResult Read(char* buffer, MxU32 size) override;
+  MxResult Write(char* buffer, MxU32 size) override;
+  MxResult Tell(MxU32* offset) override;
+  MxResult Seek(MxU32 offset) override;
+
+private:
+  char *m_buffer;
+  MxU32 m_offset;
+};
+
+#endif // MXFILE_H