Merge pull request #69961 from lawnjelly/variant_parser_optional_readahead

VariantParser make readahead optional

3 files changed, 25 insertions, 5 deletions

diff --git a/core/variant/variant_parser.cpp b/core/variant/variant_parser.cpp
index 9f500dbf5e..f122ed5f8f 100644
--- a/core/variant/variant_parser.cpp
+++ b/core/variant/variant_parser.cpp
@@ -42,7 +42,7 @@ char32_t VariantParser::Stream::get_char() {
 	}
 
 	// attempt to readahead
-	readahead_filled = _read_buffer(readahead_buffer, READAHEAD_SIZE);
+	readahead_filled = _read_buffer(readahead_buffer, readahead_enabled ? READAHEAD_SIZE : 1);
 	if (readahead_filled) {
 		readahead_pointer = 0;
 	} else {
@@ -54,10 +54,21 @@ char32_t VariantParser::Stream::get_char() {
 	return get_char();
 }
 
+bool VariantParser::Stream::is_eof() const {
+	if (readahead_enabled) {
+		return eof;
+	}
+	return _is_eof();
+}
+
 bool VariantParser::StreamFile::is_utf8() const {
 	return true;
 }
 
+bool VariantParser::StreamFile::_is_eof() const {
+	return f->eof_reached();
+}
+
 uint32_t VariantParser::StreamFile::_read_buffer(char32_t *p_buffer, uint32_t p_num_chars) {
 	// The buffer is assumed to include at least one character (for null terminator)
 	ERR_FAIL_COND_V(!p_num_chars, 0);
@@ -79,6 +90,10 @@ bool VariantParser::StreamString::is_utf8() const {
 	return false;
 }
 
+bool VariantParser::StreamString::_is_eof() const {
+	return pos > s.length();
+}
+
 uint32_t VariantParser::StreamString::_read_buffer(char32_t *p_buffer, uint32_t p_num_chars) {
 	// The buffer is assumed to include at least one character (for null terminator)
 	ERR_FAIL_COND_V(!p_num_chars, 0);
diff --git a/core/variant/variant_parser.h b/core/variant/variant_parser.h
index 6b1d095ab5..fdea355c4b 100644
--- a/core/variant/variant_parser.h
+++ b/core/variant/variant_parser.h
@@ -46,14 +46,16 @@ public:
 		bool eof = false;
 
 	protected:
+		bool readahead_enabled = true;
 		virtual uint32_t _read_buffer(char32_t *p_buffer, uint32_t p_num_chars) = 0;
+		virtual bool _is_eof() const = 0;
 
 	public:
 		char32_t saved = 0;
 
 		char32_t get_char();
 		virtual bool is_utf8() const = 0;
-		bool is_eof() const { return eof; }
+		bool is_eof() const;
 
 		Stream() {}
 		virtual ~Stream() {}
@@ -62,13 +64,14 @@ public:
 	struct StreamFile : public Stream {
 	protected:
 		virtual uint32_t _read_buffer(char32_t *p_buffer, uint32_t p_num_chars) override;
+		virtual bool _is_eof() const override;
 
 	public:
 		Ref<FileAccess> f;
 
 		virtual bool is_utf8() const override;
 
-		StreamFile() {}
+		StreamFile(bool p_readahead_enabled = true) { readahead_enabled = p_readahead_enabled; }
 	};
 
 	struct StreamString : public Stream {
@@ -79,10 +82,11 @@ public:
 
 	protected:
 		virtual uint32_t _read_buffer(char32_t *p_buffer, uint32_t p_num_chars) override;
+		virtual bool _is_eof() const override;
 
 	public:
 		virtual bool is_utf8() const override;
-		StreamString() {}
+		StreamString(bool p_readahead_enabled = true) { readahead_enabled = p_readahead_enabled; }
 	};
 
 	typedef Error (*ParseResourceFunc)(void *p_self, Stream *p_stream, Ref<Resource> &r_res, int &line, String &r_err_str);
diff --git a/scene/resources/resource_format_text.cpp b/scene/resources/resource_format_text.cpp
index 36e4a8ea37..e871ca007c 100644
--- a/scene/resources/resource_format_text.cpp
+++ b/scene/resources/resource_format_text.cpp
@@ -836,7 +836,8 @@ void ResourceLoaderText::set_translation_remapped(bool p_remapped) {
 	translation_remapped = p_remapped;
 }
 
-ResourceLoaderText::ResourceLoaderText() {}
+ResourceLoaderText::ResourceLoaderText() :
+		stream(false) {}
 
 void ResourceLoaderText::get_dependencies(Ref<FileAccess> p_f, List<String> *p_dependencies, bool p_add_types) {
 	open(p_f);