From 34b2f4ffcab7b054fb9dbac93717c3695221a184 Mon Sep 17 00:00:00 2001
From: Sam Lantinga <[EMAIL REDACTED]>
Date: Sat, 14 Sep 2024 19:18:08 -0700
Subject: [PATCH] Use non-blocking pipes for process I/O on Windows
Fixes https://github.com/libsdl-org/SDL/issues/10846
---
src/file/SDL_iostream.c | 29 ++++++++++++++++++++----
src/process/windows/SDL_windowsprocess.c | 13 +++++++++++
2 files changed, 37 insertions(+), 5 deletions(-)
diff --git a/src/file/SDL_iostream.c b/src/file/SDL_iostream.c
index 0d9f39fbb055a..41ac90fd84267 100644
--- a/src/file/SDL_iostream.c
+++ b/src/file/SDL_iostream.c
@@ -202,8 +202,17 @@ static size_t SDLCALL windows_file_read(void *userdata, void *ptr, size_t size,
if (total_need < READAHEAD_BUFFER_SIZE) {
if (!ReadFile(iodata->h, iodata->data, READAHEAD_BUFFER_SIZE, &bytes, NULL)) {
- if (GetLastError() != ERROR_HANDLE_EOF && GetLastError() != ERROR_BROKEN_PIPE) {
+ DWORD error = GetLastError();
+ switch (error) {
+ case ERROR_BROKEN_PIPE:
+ case ERROR_HANDLE_EOF:
+ break;
+ case ERROR_NO_DATA:
+ *status = SDL_IO_STATUS_NOT_READY;
+ break;
+ default:
WIN_SetError("Error reading from datastream");
+ break;
}
return 0;
}
@@ -214,8 +223,17 @@ static size_t SDLCALL windows_file_read(void *userdata, void *ptr, size_t size,
total_read += read_ahead;
} else {
if (!ReadFile(iodata->h, ptr, (DWORD)total_need, &bytes, NULL)) {
- if (GetLastError() != ERROR_HANDLE_EOF && GetLastError() != ERROR_BROKEN_PIPE) {
+ DWORD error = GetLastError();
+ switch (error) {
+ case ERROR_BROKEN_PIPE:
+ case ERROR_HANDLE_EOF:
+ break;
+ case ERROR_NO_DATA:
+ *status = SDL_IO_STATUS_NOT_READY;
+ break;
+ default:
WIN_SetError("Error reading from datastream");
+ break;
}
return 0;
}
@@ -227,7 +245,6 @@ static size_t SDLCALL windows_file_read(void *userdata, void *ptr, size_t size,
static size_t SDLCALL windows_file_write(void *userdata, const void *ptr, size_t size, SDL_IOStatus *status)
{
IOStreamWindowsData *iodata = (IOStreamWindowsData *) userdata;
- const size_t total_bytes = size;
DWORD bytes;
if (iodata->left) {
@@ -248,11 +265,13 @@ static size_t SDLCALL windows_file_write(void *userdata, const void *ptr, size_t
}
}
- if (!WriteFile(iodata->h, ptr, (DWORD)total_bytes, &bytes, NULL)) {
+ if (!WriteFile(iodata->h, ptr, (DWORD)size, &bytes, NULL)) {
WIN_SetError("Error writing to datastream");
return 0;
}
-
+ if (bytes == 0 && size > 0) {
+ *status = SDL_IO_STATUS_NOT_READY;
+ }
return bytes;
}
diff --git a/src/process/windows/SDL_windowsprocess.c b/src/process/windows/SDL_windowsprocess.c
index 6ad61403e7d95..945edf716588c 100644
--- a/src/process/windows/SDL_windowsprocess.c
+++ b/src/process/windows/SDL_windowsprocess.c
@@ -200,6 +200,7 @@ bool SDL_SYS_CreateProcessWithProperties(SDL_Process *process, SDL_PropertiesID
HANDLE stdin_pipe[2] = { INVALID_HANDLE_VALUE, INVALID_HANDLE_VALUE };
HANDLE stdout_pipe[2] = { INVALID_HANDLE_VALUE, INVALID_HANDLE_VALUE };
HANDLE stderr_pipe[2] = { INVALID_HANDLE_VALUE, INVALID_HANDLE_VALUE };
+ DWORD pipe_mode = PIPE_NOWAIT;
bool result = false;
// Keep the malloc() before exec() so that an OOM won't run a process at all
@@ -263,6 +264,10 @@ bool SDL_SYS_CreateProcessWithProperties(SDL_Process *process, SDL_PropertiesID
stdin_pipe[WRITE_END] = INVALID_HANDLE_VALUE;
goto done;
}
+ if (!SetNamedPipeHandleState(stdin_pipe[WRITE_END], &pipe_mode, NULL, NULL)) {
+ WIN_SetError("SetNamedPipeHandleState()");
+ goto done;
+ }
if (!SetHandleInformation(stdin_pipe[WRITE_END], HANDLE_FLAG_INHERIT, 0) ) {
WIN_SetError("SetHandleInformation()");
goto done;
@@ -296,6 +301,10 @@ bool SDL_SYS_CreateProcessWithProperties(SDL_Process *process, SDL_PropertiesID
stdout_pipe[WRITE_END] = INVALID_HANDLE_VALUE;
goto done;
}
+ if (!SetNamedPipeHandleState(stdout_pipe[READ_END], &pipe_mode, NULL, NULL)) {
+ WIN_SetError("SetNamedPipeHandleState()");
+ goto done;
+ }
if (!SetHandleInformation(stdout_pipe[READ_END], HANDLE_FLAG_INHERIT, 0) ) {
WIN_SetError("SetHandleInformation()");
goto done;
@@ -338,6 +347,10 @@ bool SDL_SYS_CreateProcessWithProperties(SDL_Process *process, SDL_PropertiesID
stderr_pipe[WRITE_END] = INVALID_HANDLE_VALUE;
goto done;
}
+ if (!SetNamedPipeHandleState(stderr_pipe[READ_END], &pipe_mode, NULL, NULL)) {
+ WIN_SetError("SetNamedPipeHandleState()");
+ goto done;
+ }
if (!SetHandleInformation(stderr_pipe[READ_END], HANDLE_FLAG_INHERIT, 0) ) {
WIN_SetError("SetHandleInformation()");
goto done;