Userspace: Implement basic test for framebuffer mmap

userspace/CMakeLists.txt

@@ -24,6 +24,7 @@ set(USERSPACE_PROJECTS
 	tee
 	test
 	test-globals
+	test-framebuffer
 	touch
 	u8sum
 	whoami

userspace/test-framebuffer/CMakeLists.txt

@@ -0,0 +1,16 @@
+cmake_minimum_required(VERSION 3.26)
+
+project(test-framebuffer CXX)
+
+set(SOURCES
+	main.cpp
+)
+
+add_executable(test-framebuffer ${SOURCES})
+target_compile_options(test-framebuffer PUBLIC -O2 -g)
+target_link_libraries(test-framebuffer PUBLIC libc)
+
+add_custom_target(test-framebuffer-install
+	COMMAND ${CMAKE_COMMAND} -E copy ${CMAKE_CURRENT_BINARY_DIR}/test-framebuffer ${BANAN_BIN}/
+	DEPENDS test-framebuffer
+)

userspace/test-framebuffer/main.cpp

@@ -0,0 +1,45 @@
+#include <fcntl.h>
+#include <string.h>
+#include <sys/framebuffer.h>
+#include <sys/mman.h>
+
+int main()
+{
+	int fd = open("/dev/fb0", O_RDWR);
+	if (fd == -1)
+	{
+		perror("open");
+		return 1;
+	}
+
+	framebuffer_info_t fb_info;
+	if (pread(fd, &fb_info, sizeof(fb_info), -1) == -1)
+	{
+		perror("read");
+		return 1;
+	}
+
+	size_t fb_size = fb_info.width * fb_info.height * fb_info.bpp / 8;
+
+	void* addr = mmap(nullptr, fb_size, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
+	if (addr == MAP_FAILED)
+	{
+		perror("mmap");
+		return 1;
+	}
+
+	memset(addr, 0xFF, fb_size);
+
+	if (msync(addr, fb_size, MS_SYNC) == -1)
+	{
+		perror("msync");
+		return 1;
+	}
+
+	sleep(4);
+
+	munmap(addr, fb_size);
+	close(fd);
+
+	return 0;
+}