[Lldb-commits] [lldb] [lldb][windows] refactor FileAction (PR #179274)
Charles Zablit via lldb-commits
lldb-commits at lists.llvm.org
Mon Mar 30 08:23:55 PDT 2026
https://github.com/charles-zablit updated https://github.com/llvm/llvm-project/pull/179274
>From 9ed66c8d9f6653ad27960b308570ca556ce66eef Mon Sep 17 00:00:00 2001
From: Charles Zablit <c_zablit at apple.com>
Date: Mon, 30 Mar 2026 16:23:37 +0100
Subject: [PATCH] [lldb][windows] refactor FileAction
---
lldb/include/lldb/Host/FileAction.h | 42 +++++++++--
lldb/include/lldb/Host/ProcessLaunchInfo.h | 12 +++-
.../lldb/Host/windows/WindowsFileAction.h | 72 +++++++++++++++++++
lldb/source/Host/CMakeLists.txt | 1 +
lldb/source/Host/common/ProcessLaunchInfo.cpp | 12 ++++
.../Host/windows/ProcessLauncherWindows.cpp | 30 +++++---
.../source/Host/windows/WindowsFileAction.cpp | 64 +++++++++++++++++
.../gdb-remote/GDBRemoteCommunication.cpp | 4 +-
lldb/tools/lldb-server/lldb-platform.cpp | 4 +-
lldb/unittests/Host/HostTest.cpp | 3 +-
10 files changed, 223 insertions(+), 21 deletions(-)
create mode 100644 lldb/include/lldb/Host/windows/WindowsFileAction.h
create mode 100644 lldb/source/Host/windows/WindowsFileAction.cpp
diff --git a/lldb/include/lldb/Host/FileAction.h b/lldb/include/lldb/Host/FileAction.h
index b2cc8be32d296..261cf19b81b1d 100644
--- a/lldb/include/lldb/Host/FileAction.h
+++ b/lldb/include/lldb/Host/FileAction.h
@@ -14,6 +14,10 @@
namespace lldb_private {
+/// Represents a file descriptor action to be performed during process launch.
+///
+/// FileAction encapsulates operations like opening, closing, or duplicating
+/// file descriptors that should be applied when spawning a new process.
class FileAction {
public:
enum Action {
@@ -25,30 +29,58 @@ class FileAction {
FileAction();
+ /// Reset this FileAction to its default state.
void Clear();
+ /// Configure this action to close a file descriptor.
bool Close(int fd);
+ /// Configure this action to duplicate a file descriptor.
+ ///
+ /// \param[in] fd
+ /// The file descriptor to duplicate.
+ /// \param[in] dup_fd
+ /// The target file descriptor number.
bool Duplicate(int fd, int dup_fd);
+ /// Configure this action to open a file.
+ ///
+ /// \param[in] fd
+ /// The file descriptor to use for the opened file.
+ /// \param[in] file_spec
+ /// The file to open.
+ /// \param[in] read
+ /// Open for reading.
+ /// \param[in] write
+ /// Open for writing.
bool Open(int fd, const FileSpec &file_spec, bool read, bool write);
+ /// Get the file descriptor this action applies to.
int GetFD() const { return m_fd; }
+ /// Get the type of action.
Action GetAction() const { return m_action; }
+ /// Get the action-specific argument.
+ ///
+ /// For eFileActionOpen, returns the open flags (O_RDONLY, etc.).
+ /// For eFileActionDuplicate, returns the target fd to duplicate to.
int GetActionArgument() const { return m_arg; }
+ /// Get the file specification for open actions.
const FileSpec &GetFileSpec() const;
void Dump(Stream &stream) const;
protected:
- Action m_action = eFileActionNone; // The action for this file
- int m_fd = -1; // An existing file descriptor
- int m_arg = -1; // oflag for eFileActionOpen*, dup_fd for eFileActionDuplicate
- FileSpec
- m_file_spec; // A file spec to use for opening after fork or posix_spawn
+ /// The action for this file.
+ Action m_action = eFileActionNone;
+ /// The file descriptor this action applies to.
+ int m_fd = -1;
+ /// oflag for eFileActionOpen, dup_fd for eFileActionDuplicate.
+ int m_arg = -1;
+ /// File spec to use for opening after fork or posix_spawn.
+ FileSpec m_file_spec;
};
} // namespace lldb_private
diff --git a/lldb/include/lldb/Host/ProcessLaunchInfo.h b/lldb/include/lldb/Host/ProcessLaunchInfo.h
index 7801662b244ad..69d0686b12e68 100644
--- a/lldb/include/lldb/Host/ProcessLaunchInfo.h
+++ b/lldb/include/lldb/Host/ProcessLaunchInfo.h
@@ -19,6 +19,7 @@
#include "lldb/Host/Host.h"
#ifdef _WIN32
#include "lldb/Host/windows/PseudoConsole.h"
+#include "lldb/Host/windows/WindowsFileAction.h"
#else
#include "lldb/Host/PseudoTerminal.h"
#endif
@@ -29,8 +30,10 @@ namespace lldb_private {
#if defined(_WIN32)
using PTY = PseudoConsole;
+using FileActionImpl = WindowsFileAction;
#else
using PTY = PseudoTerminal;
+using FileActionImpl = FileAction;
#endif
// ProcessLaunchInfo
@@ -46,7 +49,7 @@ class ProcessLaunchInfo : public ProcessInfo {
const FileSpec &stderr_file_spec,
const FileSpec &working_dir, uint32_t launch_flags);
- void AppendFileAction(const FileAction &info) {
+ void AppendFileAction(const FileActionImpl &info) {
m_file_actions.push_back(info);
}
@@ -54,6 +57,10 @@ class ProcessLaunchInfo : public ProcessInfo {
bool AppendDuplicateFileAction(int fd, int dup_fd);
+#ifdef _WIN32
+ bool AppendDuplicateFileAction(HANDLE fh, HANDLE dup_fh);
+#endif
+
bool AppendOpenFileAction(int fd, const FileSpec &file_spec, bool read,
bool write);
@@ -160,7 +167,8 @@ class ProcessLaunchInfo : public ProcessInfo {
std::string m_plugin_name;
FileSpec m_shell;
Flags m_flags; // Bitwise OR of bits from lldb::LaunchFlags
- std::vector<FileAction> m_file_actions; // File actions for any other files
+ std::vector<FileActionImpl>
+ m_file_actions; // File actions for any other files
std::shared_ptr<PTY> m_pty;
uint32_t m_resume_count = 0; // How many times do we resume after launching
Host::MonitorChildProcessCallback m_monitor_callback;
diff --git a/lldb/include/lldb/Host/windows/WindowsFileAction.h b/lldb/include/lldb/Host/windows/WindowsFileAction.h
new file mode 100644
index 0000000000000..fcd6f6f0b0c59
--- /dev/null
+++ b/lldb/include/lldb/Host/windows/WindowsFileAction.h
@@ -0,0 +1,72 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLDB_HOST_WINDOWS_WINDOWSFILEACTION_H
+#define LLDB_HOST_WINDOWS_WINDOWSFILEACTION_H
+
+#include "lldb/Host/FileAction.h"
+#include "lldb/lldb-types.h"
+
+typedef void *HANDLE;
+
+namespace lldb_private {
+
+/// A Windows-specific extension of FileAction that supports HANDLE-based
+/// file operations in addition to the standard file descriptor operations.
+class WindowsFileAction : public FileAction {
+public:
+ WindowsFileAction() = default;
+
+ /// Allow implicit conversion from a base FileAction. The Windows-specific
+ /// handle fields default to INVALID_HANDLE_VALUE.
+ WindowsFileAction(const FileAction &fa) : FileAction(fa) {}
+
+ /// Reset this WindowsFileAction to its default state.
+ void Clear() {
+ FileAction::Clear();
+ m_handle = LLDB_INVALID_PIPE;
+ m_arg_handle = LLDB_INVALID_PIPE;
+ }
+
+ /// Configure this action to duplicate a Windows file handle.
+ ///
+ /// \param[in] fh
+ /// The source file handle to duplicate.
+ /// \param[in] dup_fh
+ /// The target file handle.
+ bool Duplicate(HANDLE fh, HANDLE dup_fh);
+
+ /// Configure this action to associate a Windows file handle with a file.
+ ///
+ /// \param[in] fh
+ /// The file handle to use for the opened file.
+ /// \param[in] file_spec
+ /// The file to open.
+ /// \param[in] read
+ /// Open for reading.
+ /// \param[in] write
+ /// Open for writing.
+ bool Open(HANDLE fh, const FileSpec &file_spec, bool read, bool write);
+
+ /// Get the Windows HANDLE for this action's file.
+ ///
+ /// If a HANDLE was stored directly, it is returned. Otherwise, the standard
+ /// handles for STDIN/STDOUT/STDERR are returned based on the stored fd.
+ HANDLE GetHandle() const;
+
+ /// Get the Windows HANDLE argument for eFileActionDuplicate actions.
+ HANDLE GetActionArgumentHandle() const;
+
+private:
+ HANDLE m_handle = LLDB_INVALID_PIPE;
+ HANDLE m_arg_handle = LLDB_INVALID_PIPE;
+};
+
+} // namespace lldb_private
+
+#endif // LLDB_HOST_WINDOWS_WINDOWSFILEACTION_H
diff --git a/lldb/source/Host/CMakeLists.txt b/lldb/source/Host/CMakeLists.txt
index 651f3f09c471c..d52183f2f968e 100644
--- a/lldb/source/Host/CMakeLists.txt
+++ b/lldb/source/Host/CMakeLists.txt
@@ -80,6 +80,7 @@ if (CMAKE_SYSTEM_NAME MATCHES "Windows")
windows/ProcessLauncherWindows.cpp
windows/PseudoConsole.cpp
windows/ProcessRunLock.cpp
+ windows/WindowsFileAction.cpp
)
else()
add_host_subdirectory(posix
diff --git a/lldb/source/Host/common/ProcessLaunchInfo.cpp b/lldb/source/Host/common/ProcessLaunchInfo.cpp
index 2f67a417996ac..b113f807196ed 100644
--- a/lldb/source/Host/common/ProcessLaunchInfo.cpp
+++ b/lldb/source/Host/common/ProcessLaunchInfo.cpp
@@ -22,6 +22,7 @@
#ifdef _WIN32
#include "lldb/Host/windows/PseudoConsole.h"
+#include "lldb/Host/windows/WindowsFileAction.h"
#else
#include <climits>
#endif
@@ -92,6 +93,17 @@ bool ProcessLaunchInfo::AppendDuplicateFileAction(int fd, int dup_fd) {
return false;
}
+#ifdef _WIN32
+bool ProcessLaunchInfo::AppendDuplicateFileAction(HANDLE fh, HANDLE dup_fh) {
+ WindowsFileAction file_action;
+ if (file_action.Duplicate(fh, dup_fh)) {
+ AppendFileAction(file_action);
+ return true;
+ }
+ return false;
+}
+#endif
+
bool ProcessLaunchInfo::AppendOpenFileAction(int fd, const FileSpec &file_spec,
bool read, bool write) {
FileAction file_action;
diff --git a/lldb/source/Host/windows/ProcessLauncherWindows.cpp b/lldb/source/Host/windows/ProcessLauncherWindows.cpp
index fb091eb75d9b8..71091e858ffc6 100644
--- a/lldb/source/Host/windows/ProcessLauncherWindows.cpp
+++ b/lldb/source/Host/windows/ProcessLauncherWindows.cpp
@@ -9,6 +9,7 @@
#include "lldb/Host/windows/ProcessLauncherWindows.h"
#include "lldb/Host/HostProcess.h"
#include "lldb/Host/windows/PseudoConsole.h"
+#include "lldb/Host/windows/WindowsFileAction.h"
#include "lldb/Host/windows/windows.h"
#include "llvm/ADT/SmallVector.h"
@@ -255,10 +256,19 @@ llvm::ErrorOr<std::vector<HANDLE>> ProcessLauncherWindows::GetInheritedHandles(
if (launch_info) {
for (size_t i = 0; i < launch_info->GetNumFileActions(); ++i) {
- const FileAction *act = launch_info->GetFileActionAtIndex(i);
- if (act->GetAction() == FileAction::eFileActionDuplicate &&
+ const WindowsFileAction *act = static_cast<const WindowsFileAction *>(
+ launch_info->GetFileActionAtIndex(i));
+ if (std::find(inherited_handles.begin(), inherited_handles.end(),
+ act->GetHandle()) != inherited_handles.end())
+ continue;
+ if (act->GetAction() != FileAction::eFileActionDuplicate)
+ continue;
+ if (act->GetActionArgument() != -1 &&
act->GetFD() == act->GetActionArgument())
- inherited_handles.push_back(reinterpret_cast<HANDLE>(act->GetFD()));
+ inherited_handles.push_back(act->GetHandle());
+ else if (act->GetActionArgumentHandle() != INVALID_HANDLE_VALUE &&
+ act->GetHandle() == act->GetActionArgumentHandle())
+ inherited_handles.push_back(act->GetHandle());
}
}
@@ -298,16 +308,20 @@ HANDLE ProcessLauncherWindows::GetStdioHandle(const llvm::StringRef path,
DWORD share = FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE;
DWORD create = 0;
DWORD flags = 0;
- if (fd == STDIN_FILENO) {
+ switch (fd) {
+ case STDIN_FILENO:
access = GENERIC_READ;
create = OPEN_EXISTING;
flags = FILE_ATTRIBUTE_READONLY;
- }
- if (fd == STDOUT_FILENO || fd == STDERR_FILENO) {
+ break;
+ case STDERR_FILENO:
+ flags = FILE_FLAG_WRITE_THROUGH;
+ case STDOUT_FILENO:
access = GENERIC_WRITE;
create = CREATE_ALWAYS;
- if (fd == STDERR_FILENO)
- flags = FILE_FLAG_WRITE_THROUGH;
+ break;
+ default:
+ break;
}
std::wstring wpath;
diff --git a/lldb/source/Host/windows/WindowsFileAction.cpp b/lldb/source/Host/windows/WindowsFileAction.cpp
new file mode 100644
index 0000000000000..7409962145ef7
--- /dev/null
+++ b/lldb/source/Host/windows/WindowsFileAction.cpp
@@ -0,0 +1,64 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include <fcntl.h>
+
+#include "lldb/Host/PosixApi.h"
+#include "lldb/Host/windows/WindowsFileAction.h"
+#include "lldb/Host/windows/windows.h"
+
+using namespace lldb_private;
+
+bool WindowsFileAction::Duplicate(HANDLE fh, HANDLE dup_fh) {
+ Clear();
+ if (fh != INVALID_HANDLE_VALUE && dup_fh != INVALID_HANDLE_VALUE) {
+ m_action = eFileActionDuplicate;
+ m_handle = fh;
+ m_arg_handle = dup_fh;
+ return true;
+ }
+ return false;
+}
+
+bool WindowsFileAction::Open(HANDLE fh, const FileSpec &file_spec, bool read,
+ bool write) {
+ if ((read || write) && fh != INVALID_HANDLE_VALUE && file_spec) {
+ m_action = eFileActionOpen;
+ m_handle = fh;
+ if (read && write)
+ m_arg = O_NOCTTY | O_CREAT | O_RDWR;
+ else if (read)
+ m_arg = O_NOCTTY | O_RDONLY;
+ else
+ m_arg = O_NOCTTY | O_CREAT | O_WRONLY | O_TRUNC;
+ m_file_spec = file_spec;
+ return true;
+ } else {
+ Clear();
+ }
+ return false;
+}
+
+HANDLE WindowsFileAction::GetHandle() const {
+ if (m_handle != INVALID_HANDLE_VALUE)
+ return m_handle;
+ switch (m_fd) {
+ case STDIN_FILENO:
+ return GetStdHandle(STD_INPUT_HANDLE);
+ case STDOUT_FILENO:
+ return GetStdHandle(STD_OUTPUT_HANDLE);
+ case STDERR_FILENO:
+ return GetStdHandle(STD_ERROR_HANDLE);
+ default:
+ return INVALID_HANDLE_VALUE;
+ }
+}
+
+HANDLE WindowsFileAction::GetActionArgumentHandle() const {
+ return m_arg_handle;
+}
diff --git a/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunication.cpp b/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunication.cpp
index 7798abab0ad3b..781faffdc0f74 100644
--- a/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunication.cpp
+++ b/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunication.cpp
@@ -859,7 +859,7 @@ Status GDBRemoteCommunication::StartDebugserverProcess(
debugserver_args.AppendArgument(llvm::formatv("--fd={0}", *comm_fd).str());
// Send "comm_fd" down to the inferior so it can use it to communicate back
// with this process.
- launch_info.AppendDuplicateFileAction((int64_t)*comm_fd, (int64_t)*comm_fd);
+ launch_info.AppendDuplicateFileAction(*comm_fd, *comm_fd);
} else {
llvm::StringRef url = std::get<llvm::StringRef>(comm);
LLDB_LOG(log, "debugserver listens on: {0}", url);
@@ -885,7 +885,7 @@ Status GDBRemoteCommunication::StartDebugserverProcess(
pipe_t write = socket_pipe.GetWritePipe();
debugserver_args.AppendArgument(llvm::StringRef("--pipe"));
debugserver_args.AppendArgument(llvm::to_string(write));
- launch_info.AppendDuplicateFileAction((int64_t)write, (int64_t)write);
+ launch_info.AppendDuplicateFileAction(write, write);
#endif
}
diff --git a/lldb/tools/lldb-server/lldb-platform.cpp b/lldb/tools/lldb-server/lldb-platform.cpp
index bef0c61532f3c..ec2ef053241ca 100644
--- a/lldb/tools/lldb-server/lldb-platform.cpp
+++ b/lldb/tools/lldb-server/lldb-platform.cpp
@@ -325,8 +325,8 @@ static Status spawn_process(const char *progname, const FileSpec &prog,
self_args.AppendArgument(llvm::StringRef("platform"));
self_args.AppendArgument(llvm::StringRef("--child-platform-fd"));
self_args.AppendArgument(llvm::to_string(shared_socket.GetSendableFD()));
- launch_info.AppendDuplicateFileAction((int64_t)shared_socket.GetSendableFD(),
- (int64_t)shared_socket.GetSendableFD());
+ launch_info.AppendDuplicateFileAction(shared_socket.GetSendableFD(),
+ shared_socket.GetSendableFD());
if (gdb_port) {
self_args.AppendArgument(llvm::StringRef("--gdbserver-port"));
self_args.AppendArgument(llvm::to_string(gdb_port));
diff --git a/lldb/unittests/Host/HostTest.cpp b/lldb/unittests/Host/HostTest.cpp
index c88c764f24646..6ae74d3a2300b 100644
--- a/lldb/unittests/Host/HostTest.cpp
+++ b/lldb/unittests/Host/HostTest.cpp
@@ -157,8 +157,7 @@ TEST(Host, LaunchProcessDuplicatesHandle) {
"--gtest_filter=Host.LaunchProcessDuplicatesHandle");
info.GetArguments().AppendArgument(
("--test-arg=" + llvm::Twine((uint64_t)pipe.GetWritePipe())).str());
- info.AppendDuplicateFileAction((uint64_t)pipe.GetWritePipe(),
- (uint64_t)pipe.GetWritePipe());
+ info.AppendDuplicateFileAction(pipe.GetWritePipe(), pipe.GetWritePipe());
info.SetMonitorProcessCallback(&ProcessLaunchInfo::NoOpMonitorCallback);
ASSERT_THAT_ERROR(Host::LaunchProcess(info).takeError(), llvm::Succeeded());
pipe.CloseWriteFileDescriptor();
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