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-rw-r--r--source/OSSupport/File.cpp271
1 files changed, 271 insertions, 0 deletions
diff --git a/source/OSSupport/File.cpp b/source/OSSupport/File.cpp
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+++ b/source/OSSupport/File.cpp
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+
+// cFile.cpp
+
+// Implements the cFile class providing an OS-independent abstraction of a file.
+
+#include "Globals.h" // NOTE: MSVC stupidness requires this to be the same across all modules
+
+#include "File.h"
+
+
+
+
+
+
+/// Simple constructor - creates an unopened file object, use Open() to open / create a real file
+cFile::cFile(void) :
+ #ifdef USE_STDIO_FILE
+ m_File(NULL)
+ #else
+ m_File(INVALID_HANDLE_VALUE)
+ #endif // USE_STDIO_FILE
+{
+ // Nothing needed yet
+}
+
+
+
+
+
+/// Constructs and opens / creates the file specified, use IsOpen() to check for success
+cFile::cFile(const AString & iFileName, EMode iMode) :
+ #ifdef USE_STDIO_FILE
+ m_File(NULL)
+ #else
+ m_File(INVALID_HANDLE_VALUE)
+ #endif // USE_STDIO_FILE
+{
+ Open(iFileName, iMode);
+}
+
+
+
+
+
+/// Auto-closes the file, if open
+cFile::~cFile()
+{
+ if (IsOpen())
+ {
+ Close();
+ }
+}
+
+
+
+
+
+bool cFile::Open(const AString & iFileName, EMode iMode)
+{
+ ASSERT(!IsOpen()); // You should close the file before opening another one
+
+ if (IsOpen())
+ {
+ Close();
+ }
+
+ const char * Mode = NULL;
+ switch (iMode)
+ {
+ case fmRead: Mode = "rb"; break;
+ case fmWrite: Mode = "wb"; break;
+ case fmReadWrite: Mode = "rb+"; break;
+ default:
+ {
+ ASSERT(!"Unhandled file mode");
+ return false;
+ }
+ }
+ m_File = fopen( (FILE_IO_PREFIX + iFileName).c_str(), Mode);
+ if ((m_File == NULL) && (iMode == fmReadWrite))
+ {
+ // Fix for MS not following C spec, opening "a" mode files for writing at the end only
+ // The file open operation has been tried with "read update", fails if file not found
+ // So now we know either the file doesn't exist or we don't have rights, no need to worry about file contents.
+ // Simply re-open for read-writing, erasing existing contents:
+ m_File = fopen( (FILE_IO_PREFIX + iFileName).c_str(), "wb+");
+ }
+ return (m_File != NULL);
+}
+
+
+
+
+
+void cFile::Close(void)
+{
+ ASSERT(IsOpen()); // You should not close file objects that don't have an open file.
+
+ if (!IsOpen())
+ {
+ return;
+ }
+
+ fclose(m_File);
+ m_File = NULL;
+}
+
+
+
+
+
+bool cFile::IsOpen(void) const
+{
+ return (m_File != NULL);
+}
+
+
+
+
+
+bool cFile::IsEOF(void) const
+{
+ ASSERT(IsOpen());
+
+ if (!IsOpen())
+ {
+ // Unopened files behave as at EOF
+ return true;
+ }
+
+ return (feof(m_File) != 0);
+}
+
+
+
+
+
+/// Reads up to iNumBytes bytes into iBuffer, returns the number of bytes actually read, or -1 on failure; asserts if not open
+int cFile::Read (void * iBuffer, int iNumBytes)
+{
+ ASSERT(IsOpen());
+
+ if (!IsOpen())
+ {
+ return -1;
+ }
+
+ return fread(iBuffer, 1, iNumBytes, m_File); // fread() returns the portion of Count parameter actually read, so we need to send iNumBytes as Count
+}
+
+
+
+
+
+/// Writes up to iNumBytes bytes from iBuffer, returns the number of bytes actually written, or -1 on failure; asserts if not open
+int cFile::Write(const void * iBuffer, int iNumBytes)
+{
+ ASSERT(IsOpen());
+
+ if (!IsOpen())
+ {
+ return -1;
+ }
+
+ int res = fwrite(iBuffer, 1, iNumBytes, m_File); // fwrite() returns the portion of Count parameter actually written, so we need to send iNumBytes as Count
+ return res;
+}
+
+
+
+
+
+/// Seeks to iPosition bytes from file start, returns old position or -1 for failure
+int cFile::Seek (int iPosition)
+{
+ ASSERT(IsOpen());
+
+ if (!IsOpen())
+ {
+ return -1;
+ }
+
+ if (fseek(m_File, iPosition, SEEK_SET) != 0)
+ {
+ return -1;
+ }
+ return ftell(m_File);
+}
+
+
+
+
+
+
+/// Returns the current position (bytes from file start)
+int cFile::Tell (void) const
+{
+ ASSERT(IsOpen());
+
+ if (!IsOpen())
+ {
+ return -1;
+ }
+
+ return ftell(m_File);
+}
+
+
+
+
+
+/// Returns the size of file, in bytes, or -1 for failure; asserts if not open
+int cFile::GetSize(void) const
+{
+ ASSERT(IsOpen());
+
+ if (!IsOpen())
+ {
+ return -1;
+ }
+
+ int CurPos = ftell(m_File);
+ if (CurPos < 0)
+ {
+ return -1;
+ }
+ if (fseek(m_File, 0, SEEK_END) != 0)
+ {
+ return -1;
+ }
+ int res = ftell(m_File);
+ if (fseek(m_File, CurPos, SEEK_SET) != 0)
+ {
+ return -1;
+ }
+ return res;
+}
+
+
+
+
+
+int cFile::ReadRestOfFile(AString & a_Contents)
+{
+ ASSERT(IsOpen());
+
+ if (!IsOpen())
+ {
+ return -1;
+ }
+
+ int DataSize = GetSize() - Tell();
+
+ // HACK: This depends on the internal knowledge that AString's data() function returns the internal buffer directly
+ a_Contents.assign(DataSize, '\0');
+ return Read((void *)a_Contents.data(), DataSize);
+}
+
+
+
+
+
+bool cFile::Exists(const AString & a_FileName)
+{
+ cFile test(a_FileName, fmRead);
+ return test.IsOpen();
+}
+
+
+
+