Make all file access 64-bit (uint64_t)

This changes the types of a big number of variables.

General rules:
- Using `uint64_t` in general. We also considered `int64_t` but eventually
  settled on keeping it unsigned, which is also closer to what one would expect
  with `size_t`/`off_t`.
- We only keep `int64_t` for `seek_end` (takes a negative offset from the end)
  and for the `Variant` bindings, since `Variant::INT` is `int64_t`. This means
  we only need to guard against passing negative values in `core_bind.cpp`.
- Using `uint32_t` integers for concepts not needing such a huge range, like
  pages, blocks, etc.

In addition:
- Improve usage of integer types in some related places; namely, `DirAccess`,
  core binds.

Note:
- On Windows, `_ftelli64` reports invalid values when using 32-bit MinGW with
  version < 8.0. This was an upstream bug fixed in 8.0. It breaks support for
  big files on 32-bit Windows builds made with that toolchain. We might add a
  workaround.

Fixes #44363.
Fixes godotengine/godot-proposals#400.

Co-authored-by: Rémi Verschelde <rverschelde@gmail.com>

19 files changed, 40 insertions, 50 deletions

diff --git a/modules/gdnative/pluginscript/pluginscript_script.cpp b/modules/gdnative/pluginscript/pluginscript_script.cpp
index 31e6a81975..a0d7fbf726 100644
--- a/modules/gdnative/pluginscript/pluginscript_script.cpp
+++ b/modules/gdnative/pluginscript/pluginscript_script.cpp
@@ -441,10 +441,10 @@ Error PluginScript::load_source_code(const String &p_path) {
 	FileAccess *f = FileAccess::open(p_path, FileAccess::READ, &err);
 	ERR_FAIL_COND_V_MSG(err, err, "Cannot open file '" + p_path + "'.");
 
-	int len = f->get_len();
+	uint64_t len = f->get_len();
 	sourcef.resize(len + 1);
 	uint8_t *w = sourcef.ptrw();
-	int r = f->get_buffer(w, len);
+	uint64_t r = f->get_buffer(w, len);
 	f->close();
 	memdelete(f);
 	ERR_FAIL_COND_V(r != len, ERR_CANT_OPEN);
diff --git a/modules/gdnative/videodecoder/video_stream_gdnative.cpp b/modules/gdnative/videodecoder/video_stream_gdnative.cpp
index f2fb0a2fdc..1b7838846f 100644
--- a/modules/gdnative/videodecoder/video_stream_gdnative.cpp
+++ b/modules/gdnative/videodecoder/video_stream_gdnative.cpp
@@ -47,11 +47,7 @@ godot_int GDAPI godot_videodecoder_file_read(void *ptr, uint8_t *buf, int buf_si
 
 	// if file exists
 	if (file) {
-		long bytes_read = file->get_buffer(buf, buf_size);
-		// No bytes to read => EOF
-		if (bytes_read == 0) {
-			return 0;
-		}
+		int64_t bytes_read = file->get_buffer(buf, buf_size);
 		return bytes_read;
 	}
 	return -1;
@@ -62,41 +58,35 @@ int64_t GDAPI godot_videodecoder_file_seek(void *ptr, int64_t pos, int whence) {
 	FileAccess *file = reinterpret_cast<FileAccess *>(ptr);
 
 	if (file) {
-		size_t len = file->get_len();
+		int64_t len = file->get_len();
 		switch (whence) {
 			case SEEK_SET: {
-				// Just for explicitness
-				size_t new_pos = static_cast<size_t>(pos);
-				if (new_pos > len) {
+				if (pos > len) {
 					return -1;
 				}
-				file->seek(new_pos);
-				pos = static_cast<int64_t>(file->get_position());
-				return pos;
+				file->seek(pos);
+				return file->get_position();
 			} break;
 			case SEEK_CUR: {
 				// Just in case it doesn't exist
-				if (pos < 0 && (size_t)-pos > file->get_position()) {
+				if (pos < 0 && -pos > (int64_t)file->get_position()) {
 					return -1;
 				}
-				pos = pos + static_cast<int>(file->get_position());
-				file->seek(pos);
-				pos = static_cast<int64_t>(file->get_position());
-				return pos;
+				file->seek(file->get_position() + pos);
+				return file->get_position();
 			} break;
 			case SEEK_END: {
 				// Just in case something goes wrong
-				if ((size_t)-pos > len) {
+				if (-pos > len) {
 					return -1;
 				}
 				file->seek_end(pos);
-				pos = static_cast<int64_t>(file->get_position());
-				return pos;
+				return file->get_position();
 			} break;
 			default: {
 				// Only 4 possible options, hence default = AVSEEK_SIZE
 				// Asks to return the length of file
-				return static_cast<int64_t>(len);
+				return len;
 			} break;
 		}
 	}
diff --git a/modules/gdscript/gdscript.cpp b/modules/gdscript/gdscript.cpp
index 859c1acde9..9206f4095a 100644
--- a/modules/gdscript/gdscript.cpp
+++ b/modules/gdscript/gdscript.cpp
@@ -1045,10 +1045,10 @@ Error GDScript::load_source_code(const String &p_path) {
 		ERR_FAIL_COND_V(err, err);
 	}
 
-	int len = f->get_len();
+	uint64_t len = f->get_len();
 	sourcef.resize(len + 1);
 	uint8_t *w = sourcef.ptrw();
-	int r = f->get_buffer(w, len);
+	uint64_t r = f->get_buffer(w, len);
 	f->close();
 	memdelete(f);
 	ERR_FAIL_COND_V(r != len, ERR_CANT_OPEN);
diff --git a/modules/gdscript/gdscript_cache.cpp b/modules/gdscript/gdscript_cache.cpp
index 113d36be98..6aa76703f1 100644
--- a/modules/gdscript/gdscript_cache.cpp
+++ b/modules/gdscript/gdscript_cache.cpp
@@ -153,9 +153,9 @@ String GDScriptCache::get_source_code(const String &p_path) {
 		ERR_FAIL_COND_V(err, "");
 	}
 
-	int len = f->get_len();
+	uint64_t len = f->get_len();
 	source_file.resize(len + 1);
-	int r = f->get_buffer(source_file.ptrw(), len);
+	uint64_t r = f->get_buffer(source_file.ptrw(), len);
 	f->close();
 	ERR_FAIL_COND_V(r != len, "");
 	source_file.write[len] = 0;
diff --git a/modules/gdscript/tests/test_gdscript.cpp b/modules/gdscript/tests/test_gdscript.cpp
index 36da64bbaa..8ad5cdacad 100644
--- a/modules/gdscript/tests/test_gdscript.cpp
+++ b/modules/gdscript/tests/test_gdscript.cpp
@@ -215,7 +215,7 @@ void test(TestType p_type) {
 	init_language(fa->get_path_absolute().get_base_dir());
 
 	Vector<uint8_t> buf;
-	int flen = fa->get_len();
+	uint64_t flen = fa->get_len();
 	buf.resize(fa->get_len() + 1);
 	fa->get_buffer(buf.ptrw(), flen);
 	buf.write[flen] = 0;
diff --git a/modules/jpg/image_loader_jpegd.cpp b/modules/jpg/image_loader_jpegd.cpp
index 7daf6a3a57..18beff41d8 100644
--- a/modules/jpg/image_loader_jpegd.cpp
+++ b/modules/jpg/image_loader_jpegd.cpp
@@ -105,7 +105,7 @@ Error jpeg_load_image_from_buffer(Image *p_image, const uint8_t *p_buffer, int p
 
 Error ImageLoaderJPG::load_image(Ref<Image> p_image, FileAccess *f, bool p_force_linear, float p_scale) {
 	Vector<uint8_t> src_image;
-	int src_image_len = f->get_len();
+	uint64_t src_image_len = f->get_len();
 	ERR_FAIL_COND_V(src_image_len == 0, ERR_FILE_CORRUPT);
 	src_image.resize(src_image_len);
 
diff --git a/modules/mbedtls/crypto_mbedtls.cpp b/modules/mbedtls/crypto_mbedtls.cpp
index 987306af2a..4a42e9af0d 100644
--- a/modules/mbedtls/crypto_mbedtls.cpp
+++ b/modules/mbedtls/crypto_mbedtls.cpp
@@ -58,7 +58,7 @@ Error CryptoKeyMbedTLS::load(String p_path, bool p_public_only) {
 	FileAccess *f = FileAccess::open(p_path, FileAccess::READ);
 	ERR_FAIL_COND_V_MSG(!f, ERR_INVALID_PARAMETER, "Cannot open CryptoKeyMbedTLS file '" + p_path + "'.");
 
-	int flen = f->get_len();
+	uint64_t flen = f->get_len();
 	out.resize(flen + 1);
 	f->get_buffer(out.ptrw(), flen);
 	out.write[flen] = 0; // string terminator
@@ -146,7 +146,7 @@ Error X509CertificateMbedTLS::load(String p_path) {
 	FileAccess *f = FileAccess::open(p_path, FileAccess::READ);
 	ERR_FAIL_COND_V_MSG(!f, ERR_INVALID_PARAMETER, "Cannot open X509CertificateMbedTLS file '" + p_path + "'.");
 
-	int flen = f->get_len();
+	uint64_t flen = f->get_len();
 	out.resize(flen + 1);
 	f->get_buffer(out.ptrw(), flen);
 	out.write[flen] = 0; // string terminator
diff --git a/modules/minimp3/resource_importer_mp3.cpp b/modules/minimp3/resource_importer_mp3.cpp
index afd26fb79e..96cce49c86 100644
--- a/modules/minimp3/resource_importer_mp3.cpp
+++ b/modules/minimp3/resource_importer_mp3.cpp
@@ -79,7 +79,7 @@ Error ResourceImporterMP3::import(const String &p_source_file, const String &p_s
 
 	ERR_FAIL_COND_V(!f, ERR_CANT_OPEN);
 
-	size_t len = f->get_len();
+	uint64_t len = f->get_len();
 
 	Vector<uint8_t> data;
 	data.resize(len);
diff --git a/modules/mono/utils/string_utils.cpp b/modules/mono/utils/string_utils.cpp
index 43de77005e..5d53394658 100644
--- a/modules/mono/utils/string_utils.cpp
+++ b/modules/mono/utils/string_utils.cpp
@@ -170,10 +170,10 @@ Error read_all_file_utf8(const String &p_path, String &r_content) {
 	FileAccess *f = FileAccess::open(p_path, FileAccess::READ, &err);
 	ERR_FAIL_COND_V_MSG(err != OK, err, "Cannot open file '" + p_path + "'.");
 
-	int len = f->get_len();
+	uint64_t len = f->get_len();
 	sourcef.resize(len + 1);
 	uint8_t *w = sourcef.ptrw();
-	int r = f->get_buffer(w, len);
+	uint64_t r = f->get_buffer(w, len);
 	f->close();
 	memdelete(f);
 	ERR_FAIL_COND_V(r != len, ERR_CANT_OPEN);
diff --git a/modules/stb_vorbis/resource_importer_ogg_vorbis.cpp b/modules/stb_vorbis/resource_importer_ogg_vorbis.cpp
index ec1c30783a..17380001f5 100644
--- a/modules/stb_vorbis/resource_importer_ogg_vorbis.cpp
+++ b/modules/stb_vorbis/resource_importer_ogg_vorbis.cpp
@@ -79,7 +79,7 @@ Error ResourceImporterOGGVorbis::import(const String &p_source_file, const Strin
 
 	ERR_FAIL_COND_V_MSG(!f, ERR_CANT_OPEN, "Cannot open file '" + p_source_file + "'.");
 
-	size_t len = f->get_len();
+	uint64_t len = f->get_len();
 
 	Vector<uint8_t> data;
 	data.resize(len);
diff --git a/modules/svg/image_loader_svg.cpp b/modules/svg/image_loader_svg.cpp
index 6ce3e4b4b3..24fe654946 100644
--- a/modules/svg/image_loader_svg.cpp
+++ b/modules/svg/image_loader_svg.cpp
@@ -140,7 +140,7 @@ Error ImageLoaderSVG::create_image_from_string(Ref<Image> p_image, const char *p
 }
 
 Error ImageLoaderSVG::load_image(Ref<Image> p_image, FileAccess *f, bool p_force_linear, float p_scale) {
-	uint32_t size = f->get_len();
+	uint64_t size = f->get_len();
 	Vector<uint8_t> src_image;
 	src_image.resize(size + 1);
 	uint8_t *src_w = src_image.ptrw();
diff --git a/modules/text_server_adv/dynamic_font_adv.cpp b/modules/text_server_adv/dynamic_font_adv.cpp
index 326af7f0ee..faeb83f920 100644
--- a/modules/text_server_adv/dynamic_font_adv.cpp
+++ b/modules/text_server_adv/dynamic_font_adv.cpp
@@ -66,7 +66,7 @@ DynamicFontDataAdvanced::DataAtSize *DynamicFontDataAdvanced::get_data_for_size(
 					ERR_FAIL_V_MSG(nullptr, "Cannot open font file '" + font_path + "'.");
 				}
 
-				size_t len = f->get_len();
+				uint64_t len = f->get_len();
 				font_mem_cache.resize(len);
 				f->get_buffer(font_mem_cache.ptrw(), len);
 				font_mem = font_mem_cache.ptr();
diff --git a/modules/text_server_adv/text_server_adv.cpp b/modules/text_server_adv/text_server_adv.cpp
index 8b8b6b7cd3..361852547f 100644
--- a/modules/text_server_adv/text_server_adv.cpp
+++ b/modules/text_server_adv/text_server_adv.cpp
@@ -181,7 +181,7 @@ bool TextServerAdvanced::load_support_data(const String &p_filename) {
 		UErrorCode err = U_ZERO_ERROR;
 
 		// ICU data found.
-		size_t len = f->get_len();
+		uint64_t len = f->get_len();
 		icu_data = (uint8_t *)memalloc(len);
 		f->get_buffer(icu_data, len);
 		f->close();
diff --git a/modules/text_server_fb/dynamic_font_fb.cpp b/modules/text_server_fb/dynamic_font_fb.cpp
index dec1d6f83f..406f60b6f5 100644
--- a/modules/text_server_fb/dynamic_font_fb.cpp
+++ b/modules/text_server_fb/dynamic_font_fb.cpp
@@ -65,7 +65,7 @@ DynamicFontDataFallback::DataAtSize *DynamicFontDataFallback::get_data_for_size(
 					ERR_FAIL_V_MSG(nullptr, "Cannot open font file '" + font_path + "'.");
 				}
 
-				size_t len = f->get_len();
+				uint64_t len = f->get_len();
 				font_mem_cache.resize(len);
 				f->get_buffer(font_mem_cache.ptrw(), len);
 				font_mem = font_mem_cache.ptr();
diff --git a/modules/tga/image_loader_tga.cpp b/modules/tga/image_loader_tga.cpp
index ef53661557..52b92ee930 100644
--- a/modules/tga/image_loader_tga.cpp
+++ b/modules/tga/image_loader_tga.cpp
@@ -226,9 +226,9 @@ Error ImageLoaderTGA::convert_to_image(Ref<Image> p_image, const uint8_t *p_buff
 
 Error ImageLoaderTGA::load_image(Ref<Image> p_image, FileAccess *f, bool p_force_linear, float p_scale) {
 	Vector<uint8_t> src_image;
-	int src_image_len = f->get_len();
+	uint64_t src_image_len = f->get_len();
 	ERR_FAIL_COND_V(src_image_len == 0, ERR_FILE_CORRUPT);
-	ERR_FAIL_COND_V(src_image_len < (int)sizeof(tga_header_s), ERR_FILE_CORRUPT);
+	ERR_FAIL_COND_V(src_image_len < (int64_t)sizeof(tga_header_s), ERR_FILE_CORRUPT);
 	src_image.resize(src_image_len);
 
 	Error err = OK;
diff --git a/modules/theora/video_stream_theora.cpp b/modules/theora/video_stream_theora.cpp
index 54f5b3f424..7b421bdc16 100644
--- a/modules/theora/video_stream_theora.cpp
+++ b/modules/theora/video_stream_theora.cpp
@@ -58,7 +58,7 @@ int VideoStreamPlaybackTheora::buffer_data() {
 
 #else
 
-	int bytes = file->get_buffer((uint8_t *)buffer, 4096);
+	uint64_t bytes = file->get_buffer((uint8_t *)buffer, 4096);
 	ogg_sync_wrote(&oy, bytes);
 	return (bytes);
 
@@ -176,7 +176,7 @@ void VideoStreamPlaybackTheora::set_file(const String &p_file) {
 	thread_eof = false;
 	//pre-fill buffer
 	int to_read = ring_buffer.space_left();
-	int read = file->get_buffer(read_buffer.ptr(), to_read);
+	uint64_t read = file->get_buffer(read_buffer.ptr(), to_read);
 	ring_buffer.write(read_buffer.ptr(), read);
 
 	thread.start(_streaming_thread, this);
@@ -632,8 +632,8 @@ void VideoStreamPlaybackTheora::_streaming_thread(void *ud) {
 		//just fill back the buffer
 		if (!vs->thread_eof) {
 			int to_read = vs->ring_buffer.space_left();
-			if (to_read) {
-				int read = vs->file->get_buffer(vs->read_buffer.ptr(), to_read);
+			if (to_read > 0) {
+				uint64_t read = vs->file->get_buffer(vs->read_buffer.ptr(), to_read);
 				vs->ring_buffer.write(vs->read_buffer.ptr(), read);
 				vs->thread_eof = vs->file->eof_reached();
 			}
diff --git a/modules/tinyexr/image_loader_tinyexr.cpp b/modules/tinyexr/image_loader_tinyexr.cpp
index 47214e6974..cfb75fb93b 100644
--- a/modules/tinyexr/image_loader_tinyexr.cpp
+++ b/modules/tinyexr/image_loader_tinyexr.cpp
@@ -37,7 +37,7 @@
 
 Error ImageLoaderTinyEXR::load_image(Ref<Image> p_image, FileAccess *f, bool p_force_linear, float p_scale) {
 	Vector<uint8_t> src_image;
-	int src_image_len = f->get_len();
+	uint64_t src_image_len = f->get_len();
 	ERR_FAIL_COND_V(src_image_len == 0, ERR_FILE_CORRUPT);
 	src_image.resize(src_image_len);
 
diff --git a/modules/webm/video_stream_webm.cpp b/modules/webm/video_stream_webm.cpp
index a6b64b342e..15bf9dbf2d 100644
--- a/modules/webm/video_stream_webm.cpp
+++ b/modules/webm/video_stream_webm.cpp
@@ -62,10 +62,10 @@ public:
 
 	virtual int Read(long long pos, long len, unsigned char *buf) {
 		if (file) {
-			if (file->get_position() != (size_t)pos) {
+			if (file->get_position() != (uint64_t)pos) {
 				file->seek(pos);
 			}
-			if (file->get_buffer(buf, len) == len) {
+			if (file->get_buffer(buf, len) == (uint64_t)len) {
 				return 0;
 			}
 		}
@@ -74,7 +74,7 @@ public:
 
 	virtual int Length(long long *total, long long *available) {
 		if (file) {
-			const size_t len = file->get_len();
+			const uint64_t len = file->get_len();
 			if (total) {
 				*total = len;
 			}
diff --git a/modules/webp/image_loader_webp.cpp b/modules/webp/image_loader_webp.cpp
index 6e62840a3e..d7e88d76b1 100644
--- a/modules/webp/image_loader_webp.cpp
+++ b/modules/webp/image_loader_webp.cpp
@@ -147,7 +147,7 @@ static Ref<Image> _webp_mem_loader_func(const uint8_t *p_png, int p_size) {
 
 Error ImageLoaderWEBP::load_image(Ref<Image> p_image, FileAccess *f, bool p_force_linear, float p_scale) {
 	Vector<uint8_t> src_image;
-	int src_image_len = f->get_len();
+	uint64_t src_image_len = f->get_len();
 	ERR_FAIL_COND_V(src_image_len == 0, ERR_FILE_CORRUPT);
 	src_image.resize(src_image_len);