FXC as DownstreamCompiler (#1844)

* #include an absolute path didn't work - because paths were taken to always be relative.

* WIP Fxc as downstream compiler.

* First pass FXC downstream compiler working.

* GCC compile fix.

* Fix FXC parsing issue.

* Special case filesystem access.

* Use StringUtil getSlice.

* Fix isses with not emitting source for FXC.

* Small fixes for DXBC handling.

2 files changed, 10 insertions, 4 deletions

diff --git a/source/core/slang-string-util.cpp b/source/core/slang-string-util.cpp
index cddee4bc4..7a142f643 100644
--- a/source/core/slang-string-util.cpp
+++ b/source/core/slang-string-util.cpp
@@ -293,7 +293,7 @@ UnownedStringSlice StringUtil::getAtInSplit(const UnownedStringSlice& in, char s
     return builder;
 }
 
-/* static */String StringUtil::getString(ISlangBlob* blob)
+/* static */UnownedStringSlice StringUtil::getSlice(ISlangBlob* blob)
 {
     if (blob)
     {
@@ -301,15 +301,20 @@ UnownedStringSlice StringUtil::getAtInSplit(const UnownedStringSlice& in, char s
         if (size > 0)
         {
             const char* contents = (const char*)blob->getBufferPointer();
-            // Check it has terminating 0, if not we must construct as if it does
+            // Check it has terminating 0, if it has we skip it, because slices do not need zero termination 
             if (contents[size - 1] == 0)
             {
                 size--;
             }
-            return String(contents, contents + size);
+            return UnownedStringSlice(contents, contents + size);
         }
     }
-    return String();
+    return UnownedStringSlice();
+}
+
+/* static */String StringUtil::getString(ISlangBlob* blob)
+{
+    return getSlice(blob);
 }
 
 ComPtr<ISlangBlob> StringUtil::createStringBlob(const String& string)
diff --git a/source/core/slang-string-util.h b/source/core/slang-string-util.h
index 5b375a09e..2b30120b7 100644
--- a/source/core/slang-string-util.h
+++ b/source/core/slang-string-util.h
@@ -69,6 +69,7 @@ struct StringUtil
         /// Given a string held in a blob, returns as a String
         /// Returns an empty string if blob is nullptr 
     static String getString(ISlangBlob* blob);
+    static UnownedStringSlice getSlice(ISlangBlob* blob);
 
         /// Given a string or slice, replaces all instances of fromChar with toChar
     static String calcCharReplaced(const UnownedStringSlice& slice, char fromChar, char toChar);