From 125ce7137987ec91b931b4fb97d9c3c7af88c377 Mon Sep 17 00:00:00 2001
From: Anonymous Maarten <[EMAIL REDACTED]>
Date: Wed, 7 Aug 2024 23:49:02 +0200
Subject: [PATCH] SDL_Log: avoid sending text to the debug stream twice
When debugging a GUI application in Visual Studio,
text printed with fprintf(stderr) will also be sent to the debug stream.
When buiding SDL with SDL_LIBC=ON, this patch makes logging skip
OutputDebugString and rely on fprintf(stderr) to send the text to
the debugger.
---
src/SDL_log.c | 47 +++++++++++++++++++++++++++++++----------------
1 file changed, 31 insertions(+), 16 deletions(-)
diff --git a/src/SDL_log.c b/src/SDL_log.c
index 2b2680f5fdef7..000c90e642105 100644
--- a/src/SDL_log.c
+++ b/src/SDL_log.c
@@ -510,9 +510,14 @@ void SDL_LogMessageV(int category, SDL_LogPriority priority, SDL_PRINTF_FORMAT_S
}
}
-#if defined(SDL_PLATFORM_WIN32) && !defined(HAVE_STDIO_H) && !defined(SDL_PLATFORM_WINRT) && !defined(SDL_PLATFORM_GDK)
-/* Flag tracking the attachment of the console: 0=unattached, 1=attached to a console, 2=attached to a file, -1=error */
-static int consoleAttached = 0;
+#if defined(SDL_PLATFORM_WIN32) && !defined(SDL_PLATFORM_WINRT) && !defined(SDL_PLATFORM_GDK)
+enum {
+ CONSOLE_UNATTACHED = 0,
+ CONSOLE_ATTACHED_CONSOLE = 1,
+ CONSOLE_ATTACHED_FILE = 2,
+ CONSOLE_ATTACHED_MSVC = 3,
+ CONSOLE_ATTACHED_ERROR = -1,
+} consoleAttached = CONSOLE_UNATTACHED;
/* Handle to stderr output of console. */
static HANDLE stderrHandle = NULL;
@@ -530,58 +535,68 @@ static void SDLCALL SDL_LogOutput(void *userdata, int category, SDL_LogPriority
LPTSTR tstr;
SDL_bool isstack;
-#if !defined(HAVE_STDIO_H) && !defined(SDL_PLATFORM_WINRT) && !defined(SDL_PLATFORM_GDK)
+#if !defined(SDL_PLATFORM_WINRT) && !defined(SDL_PLATFORM_GDK)
BOOL attachResult;
DWORD attachError;
- DWORD charsWritten;
DWORD consoleMode;
+#if !defined(HAVE_STDIO_H)
+ DWORD charsWritten;
+#endif
/* Maybe attach console and get stderr handle */
- if (consoleAttached == 0) {
+ if (consoleAttached == CONSOLE_UNATTACHED) {
attachResult = AttachConsole(ATTACH_PARENT_PROCESS);
if (!attachResult) {
attachError = GetLastError();
if (attachError == ERROR_INVALID_HANDLE) {
/* This is expected when running from Visual Studio */
/*OutputDebugString(TEXT("Parent process has no console\r\n"));*/
- consoleAttached = -1;
+ consoleAttached = CONSOLE_ATTACHED_MSVC;
} else if (attachError == ERROR_GEN_FAILURE) {
OutputDebugString(TEXT("Could not attach to console of parent process\r\n"));
- consoleAttached = -1;
+ consoleAttached = CONSOLE_ATTACHED_ERROR;
} else if (attachError == ERROR_ACCESS_DENIED) {
/* Already attached */
- consoleAttached = 1;
+ consoleAttached = CONSOLE_ATTACHED_CONSOLE;
} else {
OutputDebugString(TEXT("Error attaching console\r\n"));
- consoleAttached = -1;
+ consoleAttached = CONSOLE_ATTACHED_ERROR;
}
} else {
/* Newly attached */
- consoleAttached = 1;
+ consoleAttached = CONSOLE_ATTACHED_CONSOLE;
}
- if (consoleAttached == 1) {
+ if (consoleAttached == CONSOLE_ATTACHED_CONSOLE) {
stderrHandle = GetStdHandle(STD_ERROR_HANDLE);
if (GetConsoleMode(stderrHandle, &consoleMode) == 0) {
/* WriteConsole fails if the output is redirected to a file. Must use WriteFile instead. */
- consoleAttached = 2;
+ consoleAttached = CONSOLE_ATTACHED_FILE;
}
}
}
#endif /* !defined(HAVE_STDIO_H) && !defined(SDL_PLATFORM_WINRT) && !defined(SDL_PLATFORM_GDK) */
-
length = SDL_strlen(SDL_GetLogPriorityPrefix(priority)) + SDL_strlen(message) + 1 + 1 + 1;
output = SDL_small_alloc(char, length, &isstack);
(void)SDL_snprintf(output, length, "%s%s\r\n", SDL_GetLogPriorityPrefix(priority), message);
tstr = WIN_UTF8ToString(output);
+
+#if defined(HAVE_STDIO_H) && !defined(SDL_PLATFORM_WINRT) && !defined(SDL_PLATFORM_GDK)
+ /* When running in MSVC and using stdio, rely on forwarding of stderr to the debug stream */
+ if (consoleAttached != CONSOLE_ATTACHED_MSVC) {
+ /* Output to debugger */
+ OutputDebugString(tstr);
+ }
+#else
/* Output to debugger */
OutputDebugString(tstr);
+#endif
#if !defined(HAVE_STDIO_H) && !defined(SDL_PLATFORM_WINRT) && !defined(SDL_PLATFORM_GDK)
/* Screen output to stderr, if console was attached. */
- if (consoleAttached == 1) {
+ if (consoleAttached == CONSOLE_ATTACHED_CONSOLE) {
if (!WriteConsole(stderrHandle, tstr, (DWORD)SDL_tcslen(tstr), &charsWritten, NULL)) {
OutputDebugString(TEXT("Error calling WriteConsole\r\n"));
if (GetLastError() == ERROR_NOT_ENOUGH_MEMORY) {
@@ -589,7 +604,7 @@ static void SDLCALL SDL_LogOutput(void *userdata, int category, SDL_LogPriority
}
}
- } else if (consoleAttached == 2) {
+ } else if (consoleAttached == CONSOLE_ATTACHED_FILE) {
if (!WriteFile(stderrHandle, output, (DWORD)SDL_strlen(output), &charsWritten, NULL)) {
OutputDebugString(TEXT("Error calling WriteFile\r\n"));
}