add an example unbufcpy3 based on unbufcpy1, but use coroutine!

example/unbufcpy/CMakeLists.txt

@@ -1,5 +1,7 @@
 
 add_executable(unbufcp1 unbufcp1/unbufcp1.c)
 add_executable(unbufcp2 unbufcp2/unbufcp2.cpp)
+add_executable(unbufcp3 unbufcp3/unbufcp3.cpp)
 set_target_properties(unbufcp1 PROPERTIES FOLDER "examples")
 set_target_properties(unbufcp2 PROPERTIES FOLDER "examples")
+set_target_properties(unbufcp3 PROPERTIES FOLDER "examples")

example/unbufcpy/unbufcp3/unbufcp3.cpp

@@ -0,0 +1,294 @@
+/*++
+THIS CODE AND INFORMATION IS PROVIDED "AS IS" WITHOUT WARRANTY OF
+ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING BUT NOT LIMITED
+TO THE IMPLIED WARRANTIES OF MERCHANTABILITY AND/OR FITNESS FOR A
+PARTICULAR PURPOSE.
+
+Copyright (C) 2024 - 2025.  microcai.  All rights reserved.
+
+Module Name:
+
+    unbufcp3.cpp
+
+Abstract:
+
+    This single-threaded version shows how to multiplex I/O to a number of files with
+    a single thread. This is the most efficient mechanism if you do not need the
+    asynchronous completion model that the dual-threaded version offers.
+
+    Only one thread and one I/O completion port is used. The file handles for the
+    source and destination file are both associated with the same port.  The
+    thread starts off by posting a number of overlapped
+    reads from the source file.  It then waits on the I/O completion port.
+    Whenever a read completes, it immediately turns it around into a write to
+    the destination file. Whenever a write completes, it immediately posts the
+    next read from the source file.
+
+    Thread 1
+       |
+       |
+    kick off a few
+    overlapped reads
+       |
+       |
+  ->GetQueuedCompletionStatus(WritePort) <-----------
+  |    |                                            |
+  |    |-------------------------------             |
+  |    |                              |             |
+  | write has completed,      read has completed,   |
+  | kick off another          kick off the write.   |
+  | read                              |             |
+  |    |                              |             |
+  |____|                              |_____________|
+
+--*/
+#define BUFFER_SIZE (1024*1024*16)
+
+#include "universal_async.hpp"
+#include "universal_fiber.hpp"
+
+#include <chrono>
+
+//
+// Define the size of the buffers used to do the I/O.
+// 64K is a nice number.
+//
+
+//
+// The system's page size will always be a multiple of the
+// sector size. Do all I/Os in page-size chunks.
+//
+DWORD PageSize;
+
+static void copy_coroutine(HANDLE IoPort, std::string sourcefilename, std::string destfilename)
+{
+	ULARGE_INTEGER FileSize;
+	ULARGE_INTEGER InitialSize;
+
+    auto StartTime = std::chrono::steady_clock::now();
+
+	//
+	// Open the source file and create the destination file.
+	// Use FILE_FLAG_NO_BUFFERING to avoid polluting the
+	// system cache with two copies of the same data.
+	//
+
+	HANDLE SourceFile = CreateFileA(sourcefilename.c_str(),
+		GENERIC_READ | GENERIC_WRITE,
+		FILE_SHARE_READ,
+		NULL,
+		OPEN_EXISTING,
+		FILE_FLAG_NO_BUFFERING | FILE_FLAG_OVERLAPPED,
+		NULL);
+	if (SourceFile == INVALID_HANDLE_VALUE) {
+		fprintf(stderr, "failed to open %s, error %d\n", sourcefilename.c_str(), GetLastError());
+		exit(1);
+	}
+	FileSize.LowPart = GetFileSize(SourceFile, &FileSize.HighPart);
+	if ((FileSize.LowPart == 0xffffffff) && (GetLastError() != NO_ERROR)) {
+		fprintf(stderr, "GetFileSize failed, error %d\n", GetLastError());
+		exit(1);
+	}
+
+	HANDLE DestFile = CreateFileA(destfilename.c_str(),
+		GENERIC_WRITE,
+		FILE_SHARE_READ,
+		NULL,
+		CREATE_ALWAYS,
+		FILE_FLAG_NO_BUFFERING | FILE_FLAG_OVERLAPPED,
+		SourceFile);
+	if (DestFile == INVALID_HANDLE_VALUE) {
+		fprintf(stderr, "failed to open %s, error %d\n", destfilename.c_str(), GetLastError());
+		exit(1);
+	}
+
+	//
+	// Extend the destination file so that the filesystem does not
+	// turn our asynchronous writes into synchronous ones.
+	//
+	InitialSize.QuadPart = (FileSize.QuadPart + PageSize - 1) & ~((DWORD_PTR)(PageSize - 1));
+	auto Status = SetFilePointer(DestFile,
+		InitialSize.LowPart,
+		(PLONG)&InitialSize.HighPart,
+		FILE_BEGIN);
+	if ((Status == INVALID_SET_FILE_POINTER) && (GetLastError() != NO_ERROR)) {
+		fprintf(stderr, "initial SetFilePointer failed, error %d\n", GetLastError());
+		exit(1);
+	}
+	auto Success = SetEndOfFile(DestFile);
+	if (!Success) {
+		fprintf(stderr, "SetEndOfFile failed, error %d\n", GetLastError());
+		exit(1);
+	}
+
+	SetFilePointer(DestFile, 0, 0, FILE_BEGIN);
+
+	bind_stackfull_iocp(SourceFile, IoPort);
+	bind_stackfull_iocp(DestFile, IoPort);
+
+	FiberOVERLAPPED read_ov, write_ov;
+    read_ov.set_offset(0);
+    write_ov.set_offset(0);
+
+    char* pri_buf, *back_buf;
+	std::array<char*, 2> buffer;
+
+	pri_buf = buffer[0] = (char*) malloc(BUFFER_SIZE);
+	back_buf = buffer[1] = (char*) malloc(BUFFER_SIZE);
+
+	DWORD readLength = 0, back_readLength = 0, written = 0;
+	auto ret = ReadFile(SourceFile, pri_buf, BUFFER_SIZE, &readLength, &read_ov);
+    read_ov.last_error = GetLastError();
+	if (!(!ret && read_ov.last_error != ERROR_IO_PENDING && read_ov.last_error != ERROR_MORE_DATA))
+		readLength = get_overlapped_result(read_ov);
+
+	while (readLength > 0)
+	{
+        read_ov.add_offset(readLength);
+		ret = ReadFile(SourceFile, back_buf, BUFFER_SIZE, &back_readLength, &read_ov);
+        read_ov.last_error = GetLastError();
+
+		bool read_file_pending = !(!ret && read_ov.last_error != ERROR_IO_PENDING && read_ov.last_error != ERROR_MORE_DATA);
+
+		auto result = WriteFile(DestFile, pri_buf, (readLength + PageSize - 1) & ~(PageSize - 1), &written, &write_ov);
+        write_ov.last_error = WSAGetLastError();
+		if (!(!result && write_ov.last_error != ERROR_IO_PENDING))
+		{
+            written = get_overlapped_result(write_ov);
+		}
+        write_ov.add_offset(written);
+
+		if (write_ov.last_error)
+		{
+			if (read_file_pending)
+			{
+				// socket 发送错误，取消已经投递的文件读取请求
+				CancelIoEx(SourceFile, &read_ov);
+				// 无视取消是否成功，都等待文件读取请求。
+				// 如果取消失败，（比如实际上文件已经读取成功）
+				// 那么就当是无所谓了。
+				// 如果取消成功，则 get_overlapped_result 会返回个错误
+				// 但是不管 get_overlapped_result 返回的是啥，都已经无关紧要了
+				// 这里还要调用 get_overlapped_result 仅仅是为了避免 退出本
+				// 协程后，&file_ov 已经被系统 API给引用，防止野指针问题.
+				back_readLength = get_overlapped_result(read_ov);
+				// 现在，可以安全的执行 co_return -1 退出协程了.
+			}
+
+			exit(1);
+		}
+
+		if (read_file_pending)
+		{
+			back_readLength = get_overlapped_result(read_ov);
+		}
+		readLength = back_readLength;
+		std::swap(pri_buf, back_buf);
+	}
+    //
+    // All done. There is no need to call VirtualFree() to free CopyChunk
+    // buffers here. The buffers will be freed when this process exits.
+    //
+
+    CloseHandle(SourceFile);
+    CloseHandle(DestFile);
+
+    //
+    // We need another handle to the destination file that is
+    // opened without FILE_FLAG_NO_BUFFERING. This allows us to set
+    // the end-of-file marker to a position that is not sector-aligned.
+    //
+    HANDLE BufferedHandle = CreateFileA(destfilename.c_str(),
+                                GENERIC_WRITE,
+                                FILE_SHARE_READ | FILE_SHARE_WRITE,
+                                NULL,
+                                OPEN_EXISTING,
+                                0,
+                                NULL);
+    if (BufferedHandle == INVALID_HANDLE_VALUE) {
+        fprintf(stderr,
+                "failed to open buffered handle to %s, error %d\n",
+                destfilename.c_str(),
+                GetLastError());
+        exit(1);
+    }
+
+
+    //
+    // Set the destination's file size to the size of the
+    // source file, in case the size of the source file was
+    // not a multiple of the page size.
+    //
+    Status = SetFilePointer(BufferedHandle,
+                            FileSize.LowPart,
+                            (PLONG)&FileSize.HighPart,
+                            FILE_BEGIN);
+    if ((Status == INVALID_SET_FILE_POINTER) && (GetLastError() != NO_ERROR)) {
+        fprintf(stderr, "final SetFilePointer failed, error %d\n", GetLastError());
+        exit(1);
+    }
+    Success = SetEndOfFile(BufferedHandle);
+    if (!Success) {
+        fprintf(stderr, "SetEndOfFile failed, error %d\n", GetLastError());
+        exit(1);
+    }
+    CloseHandle(BufferedHandle);
+
+    auto EndTime = std::chrono::steady_clock::now();
+
+    auto duration = EndTime - StartTime;
+    auto dur_sec = std::chrono::duration_cast<std::chrono::milliseconds>(duration).count() / 1000.0f;
+
+    printf("%llu bytes copied in %.3f seconds\n", FileSize.QuadPart, dur_sec);
+    printf("%.2f MB/sec\n", ((LONGLONG)FileSize.QuadPart/(1024.0*1024.0)) / dur_sec);
+
+
+	create_detached_coroutine(std::bind(&copy_coroutine, IoPort, sourcefilename, destfilename));
+	//exit(0);
+}
+
+
+int main(int argc, char* argv[])
+{
+
+	//
+	// I/O completion port. All read and writes to the files complete
+	// to this port.
+	//
+	HANDLE IoPort;
+
+	if (argc != 3) {
+		fprintf(stderr, "Usage: %s SourceFile DestinationFile\n", argv[0]);
+		exit(1);
+	}
+
+#ifdef _WIN32
+	SYSTEM_INFO SystemInfo;
+	GetSystemInfo(&SystemInfo);
+	PageSize = SystemInfo.dwPageSize;
+#else
+	PageSize = 4096;
+#endif
+
+	//
+	//we are running on NT 3.51 or greater.
+	//Create the I/O Completion Port
+	//
+	IoPort = CreateIoCompletionPort(INVALID_HANDLE_VALUE,//file handle to associate with I/O completion port
+		NULL,                //optional handle to existing I/O completion port
+		0,                            //completion key
+		1);               //# of threads allowed to execute concurrently
+
+
+	if (IoPort == NULL) {
+		fprintf(stderr, "failed to create ReadPort, error %d\n", GetLastError());
+		exit(1);
+	}
+
+	//
+	// Do the copy
+	//
+	create_detached_coroutine(std::bind(&copy_coroutine, IoPort, std::string(argv[1]), std::string(argv[2])));
+
+	iocp::run_event_loop(IoPort);
+}

uasync/include/universal_fiber.hpp

@@ -184,7 +184,11 @@ struct FiberCallableArgument
 	alignas(64) char callable_storage[sizeof(Callable)];
 };
 
-inline constexpr std::size_t FiberContextSize = 65536;
+#ifndef COROTINE_STACK_SIZE
+#define COROTINE_STACK_SIZE 65536
+#endif
+
+inline constexpr std::size_t FiberContextSize = COROTINE_STACK_SIZE;
 
 template<typename Callable>
 struct FiberContext