Feature/include refactor (#675)

* Refactor of path handling.
* Added PathInfo
* Changed ISlangFileSystem - such that has separate concepts of reading a file, getting a relative path and getting a canonical path
* Added support for getting a canonical path for windows/linux
* Made maps/testing around canonicalPaths
* User output remains around 'foundPath' - which is the same as before

* Small improvements around PathInfo
* Added a type and make constructors to make clear the different 'path' uses
* Fixed bug in findViewRecursively

* Checking and reporting for ignored #pragma once.

* Removed SLANG_PATH_TYPE_NONE as doesn't serve any useful purpose.

* Improve comments in slang.h aroung ISlangFileSystem

* Remove the need for <windows.h> in slang-io.cpp

* Ran premake5.

* Improvements and fixes around PathInfo.

* Fix typo on linix GetCanonical

* Make the ISlangFileSystem the same as before, and ISlangFileSystem contain the new methods.
Internally it always uses the ISlangFileSystemExt, and will wrap a ISlangFileSystem with WrapFileSystem, if it is determined (via queryInterface) that it doesn't implement the full interface.

1 files changed, 81 insertions, 0 deletions

diff --git a/source/slang/include-file-system.h b/source/slang/include-file-system.h
new file mode 100644
index 000000000..4b34c2a0f
--- /dev/null
+++ b/source/slang/include-file-system.h
@@ -0,0 +1,81 @@
+#ifndef SLANG_INCLUDE_FILE_SYSTEM_H_INCLUDED
+#define SLANG_INCLUDE_FILE_SYSTEM_H_INCLUDED
+
+#include "../../slang.h"
+#include "../../slang-com-helper.h"
+#include "../../slang-com-ptr.h"
+
+namespace Slang
+{
+
+class IncludeFileSystem : public ISlangFileSystemExt
+{
+public:
+    // ISlangUnknown
+    SLANG_IUNKNOWN_ALL
+        
+    // ISlangFileSystem
+    virtual SLANG_NO_THROW SlangResult SLANG_MCALL loadFile(
+        char const*     path,
+        ISlangBlob**    outBlob) SLANG_OVERRIDE;
+
+    // ISlangFileSystemExt
+    virtual SLANG_NO_THROW SlangResult SLANG_MCALL getCanoncialPath(
+            const char* path,
+            ISlangBlob** canonicalPathOut) SLANG_OVERRIDE;
+
+    virtual SLANG_NO_THROW SlangResult SLANG_MCALL calcRelativePath(
+        SlangPathType fromPathType,
+        const char* fromPath,
+        const char* path,
+        ISlangBlob** pathOut) SLANG_OVERRIDE;
+
+        /// Get a default instance
+    static ISlangFileSystemExt* getDefault();
+
+protected:
+  
+        /// If no ref, add one to the ref
+    void ensureRef() { m_refCount += (m_refCount == 0); }
+
+    ISlangUnknown* getInterface(const Guid& guid);
+    uint32_t m_refCount = 0;
+};
+
+/* Wraps an ISlangFileSystem, and provides the extra methods required to make a ISlangFileSystemExt 
+interface, deferring to the contained file system to do reading. 
+
+NOTE! That this behavior is the same as previously in that.... 
+1) getRelativePath, just returns the path as processed by the Path:: methods 
+2) getCanonicalPath, just returns the input path as the 'canonical' path. This will be wrong with a file multiply referenced through paths with .. and or . but 
+doing it this way means it works as before and requires no new functions.
+*/
+class WrapFileSystem : public IncludeFileSystem
+{
+public:
+    // So we don't need virtual dtor
+    SLANG_IUNKNOWN_RELEASE
+
+    // ISlangFileSystem
+    virtual SLANG_NO_THROW SlangResult SLANG_MCALL loadFile(
+        char const*     path,
+        ISlangBlob**    outBlob) SLANG_OVERRIDE;
+
+    // ISlangFileSystemExt
+    virtual SLANG_NO_THROW SlangResult SLANG_MCALL getCanoncialPath(
+        const char* path,
+        ISlangBlob** canonicalPathOut) SLANG_OVERRIDE;
+
+        /// Ctor
+    WrapFileSystem(ISlangFileSystem* fileSystem):
+        m_fileSystem(fileSystem)
+    {
+    }
+
+protected:
+    ComPtr<ISlangFileSystem> m_fileSystem;                  ///< The wrapped file system
+};
+
+}
+
+#endif
\ No newline at end of file