From f354c0ec3f1c5472e6dca21ff01dde123b835364 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Micha=C5=82=20Janiszewski?= <janisozaur@gmail.com>
Date: Tue, 6 Sep 2016 14:55:44 +0200
Subject: [PATCH] Fix testpaint target for Linux

---
 CMakeLists.txt          |  2 +-
 src/openrct2.c          |  2 +-
 test/testpaint/main.cpp | 99 +++++++++++++++++++++++++++++++++++++++++
 3 files changed, 101 insertions(+), 2 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index ae260cfc2d..7ab7d3572f 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -370,7 +370,7 @@ file(GLOB_RECURSE ORCT2_RIDE_SOURCES "src/ride/*/*.c")
 file(GLOB_RECURSE ORCT2_RIDE_DEP_SOURCES "src/ride/ride_data.c" "src/ride/track_data.c" "src/ride/track_paint.c" "src/addresses.c" "src/diagnostic.c" "src/hook.c" "src/paint/map_element/map_element.c")
 file(GLOB_RECURSE ORCT2_PAINT_TEST_SOURCES "test/testpaint/*.c" "test/testpaint/*.cpp" "test/testpaint/*.h")
 
-add_executable(testpaint EXCLUDE_FROM_ALL ${ORCT2_RIDE_SOURCES} ${ORCT2_RIDE_DEP_SOURCES} ${ORCT2_PAINT_TEST_SOURCES})
+add_executable(testpaint EXCLUDE_FROM_ALL ${ORCT2_RIDE_SOURCES} ${ORCT2_RIDE_DEP_SOURCES} ${ORCT2_PAINT_TEST_SOURCES} ${RCT2_SECTIONS})
 set_target_properties(testpaint PROPERTIES COMPILE_FLAGS "-DNO_VEHICLES")
 add_dependencies(testpaint segfiles)
 
diff --git a/src/openrct2.c b/src/openrct2.c
index 94a9546c67..44c980e5c7 100644
--- a/src/openrct2.c
+++ b/src/openrct2.c
@@ -594,7 +594,7 @@ bool openrct2_setup_rct2_segment()
 	}
 #if !defined(USE_MMAP)
 	// section: text
-	err = mprotect((void *)0x401000, 0x8a4000 - 0x401000, PROT_READ | PROT_EXEC);
+	err = mprotect((void *)0x401000, 0x8a4000 - 0x401000, PROT_READ | PROT_EXEC | PROT_WRITE);
 	if (err != 0)
 	{
 		perror("mprotect");
diff --git a/test/testpaint/main.cpp b/test/testpaint/main.cpp
index cf4e3572b2..7e3ac58b90 100644
--- a/test/testpaint/main.cpp
+++ b/test/testpaint/main.cpp
@@ -18,6 +18,11 @@
 #include <string>
 #include <vector>
 
+#if defined(__unix__)
+#include <unistd.h>
+#include <sys/mman.h>
+#endif // defined(__unix__)
+
 extern "C" {
 #include "data.h"
 #include "intercept.h"
@@ -124,6 +129,99 @@ __declspec(dllexport) int StartOpenRCT(HINSTANCE hInstance, HINSTANCE hPrevInsta
 
 #endif
 
+char *segments = (char *)(GOOD_PLACE_FOR_DATA_SEGMENT);
+
+static uint32 sawyercoding_calculate_checksum(const uint8* buffer, size_t length)
+{
+	size_t i;
+	uint32 checksum = 0;
+	for (i = 0; i < length; i++)
+		checksum += buffer[i];
+
+	return checksum;
+}
+
+/**
+ * Loads RCT2's data model and remaps the addresses.
+ * @returns true if the data integrity check succeeded, otherwise false.
+ */
+static bool openrct2_setup_rct2_segment()
+{
+	// OpenRCT2 on Linux and macOS is wired to have the original Windows PE sections loaded
+	// necessary. Windows does not need to do this as OpenRCT2 runs as a DLL loaded from the Windows PE.
+	int len = 0x01429000 - 0x8a4000; // 0xB85000, 12079104 bytes or around 11.5MB
+	int err = 0;
+
+#if defined(__unix__)
+	int pageSize = getpagesize();
+	int numPages = (len + pageSize - 1) / pageSize;
+	unsigned char *dummy = (unsigned char *)malloc(numPages);
+
+	err = mincore((void *)segments, len, dummy);
+	bool pagesMissing = false;
+	if (err != 0)
+	{
+		err = errno;
+#ifdef __LINUX__
+		// On Linux ENOMEM means all requested range is unmapped
+		if (err != ENOMEM)
+		{
+			pagesMissing = true;
+			perror("mincore");
+		}
+#else
+		pagesMissing = true;
+		perror("mincore");
+#endif // __LINUX__
+	} else {
+		for (int i = 0; i < numPages; i++)
+		{
+			if (dummy[i] != 1)
+			{
+				pagesMissing = true;
+				void *start = (void *)(segments + i * pageSize);
+				void *end = (void *)(segments + (i + 1) * pageSize - 1);
+				log_warning("required page %p - %p is not in memory!", start, end);
+			}
+		}
+	}
+	free(dummy);
+	if (pagesMissing)
+	{
+		log_error("At least one of required pages was not found in memory. This can cause segfaults later on.");
+	}
+
+	// section: text
+	err = mprotect((void *)0x401000, 0x8a4000 - 0x401000, PROT_READ | PROT_EXEC | PROT_WRITE);
+	if (err != 0)
+	{
+		perror("mprotect");
+	}
+
+	// section: rw data
+	err = mprotect((void *)segments, 0x01429000 - 0x8a4000, PROT_READ | PROT_WRITE);
+	if (err != 0)
+	{
+		perror("mprotect");
+	}
+#endif // defined(__unix__)
+
+	// Check that the expected data is at various addresses.
+	// Start at 0x9a6000, which is start of .data, to skip the region containing addresses to DLL
+	// calls, which can be changed by windows/wine loader.
+	const uint32 c1 = sawyercoding_calculate_checksum((const uint8*)(segments + (uintptr_t)(0x009A6000 - 0x8a4000)), 0x009E0000 - 0x009A6000);
+	const uint32 c2 = sawyercoding_calculate_checksum((const uint8*)(segments + (uintptr_t)(0x01428000 - 0x8a4000)), 0x014282BC - 0x01428000);
+	const uint32 exp_c1 = 10114815;
+	const uint32 exp_c2 = 23564;
+	if (c1 != exp_c1 || c2 != exp_c2) {
+		log_warning("c1 = %u, expected %u, match %d", c1, exp_c1, c1 == exp_c1);
+		log_warning("c2 = %u, expected %u, match %d", c2, exp_c2, c2 == exp_c2);
+		return false;
+	}
+
+	return true;
+}
+
 int main(int argc, char *argv[]) {
 	std::vector<TestCase> testCases;
 
@@ -166,6 +264,7 @@ int main(int argc, char *argv[]) {
 
 	ColouredPrintF(CLIColour::GREEN, "[----------] ");
 	printf("Global test environment set-up.\n");
+	openrct2_setup_rct2_segment();
 	initHooks();
 
 	int successCount = 0;