whytofly
/
qt6-bb10
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Logging: make qEmergencyOut() not allocate from the heap 

Commit 6e6b74c0 introduced heap allocation in the form of
QString::fromLatin1().utf16() into qEmergencyOut(), a function
that's called in OOM situations and in cases where another
exception is still in flight.

Luckily, QString::fromLatin1().utf16() is just a funny way of
copying an array of chars into an array of wchar_ts, so we do
that manually now and use a static wchar_t buffer. While at it,
also throw text elision into the mix.

This commit also fixes the message passed to _CrtDbgReportW().
What should be displayed is the emergency_buf, not the format
string.

Also remove a similar allocation in qt_message_output().

Change-Id: I2c44a298fc0927bb992de4977a7e4a7b47b16b26
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>
bb10
Marc Mutz 2012-08-03 09:32:05 +02:00 committed by Qt by Nokia
parent a3e563c091
commit 6d56a21621
1 changed files with 38 additions and 11 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

49
src/corelib/global/qlogging.cpp
View File

@ -93,6 +93,22 @@ QT_BEGIN_NAMESPACE
extern bool usingWinMain;
#endif
#if defined(Q_OS_WIN) && defined(QT_BUILD_CORE_LIB) || defined(Q_CC_MSVC) && defined(QT_DEBUG) && defined(_DEBUG) && defined(_CRT_ERROR)
static void convert_to_wchar_t_elided(wchar_t *d, size_t space, const char *s) Q_DECL_NOEXCEPT
{
size_t len = qstrlen(s);
if (len + 1 > space) {
const size_t skip = len - space + 4; // 4 for "..." + '\0'
s += skip;
for (int i = 0; i < 3; ++i)
*d++ = L'.';
}
while (*s)
*d++ = *s++;
*d++ = 0;
}
#endif
#if !defined(QT_NO_EXCEPTIONS)
/*!
\internal
@ -103,22 +119,26 @@ extern bool usingWinMain;
static void qEmergencyOut(QtMsgType msgType, const char *msg, va_list ap) Q_DECL_NOEXCEPT
{
char emergency_buf[256] = { '\0' };
emergency_buf[255] = '\0';
emergency_buf[sizeof emergency_buf - 1] = '\0';
#if defined(Q_OS_WIN) && defined(QT_BUILD_CORE_LIB) || defined(Q_CC_MSVC) && defined(QT_DEBUG) && defined(_DEBUG) && defined(_CRT_ERROR)
wchar_t emergency_bufL[sizeof emergency_buf];
#endif
if (msg)
qvsnprintf(emergency_buf, 255, msg, ap);
qvsnprintf(emergency_buf, sizeof emergency_buf - 1, msg, ap);
#if defined(Q_OS_WIN) && defined(QT_BUILD_CORE_LIB)
#ifdef Q_OS_WINCE
OutputDebugStringW(reinterpret_cast<const wchar_t *> (
QString::fromLatin1(emergency_buf).utf16()));
#else
# ifdef Q_OS_WINCE
convert_to_wchar_t_elided(emergency_bufL, sizeof emergency_buf, emergency_buf);
OutputDebugStringW(emergency_bufL);
# else
if (usingWinMain) {
OutputDebugStringA(emergency_buf);
} else {
fprintf(stderr, "%s", emergency_buf);
fflush(stderr);
}
#endif
# endif
#else
fprintf(stderr, "%s", emergency_buf);
fflush(stderr);
@ -131,10 +151,12 @@ static void qEmergencyOut(QtMsgType msgType, const char *msg, va_list ap) Q_DECL
// get the current report mode
int reportMode = _CrtSetReportMode(_CRT_ERROR, _CRTDBG_MODE_WNDW);
_CrtSetReportMode(_CRT_ERROR, reportMode);
# ifndef Q_OS_WINCE // otherwise already converted to wchar_t above
convert_to_wchar_t_elided(emergency_bufL, sizeof emergency_buf, emergency_buf);
# endif
int ret = _CrtDbgReportW(_CRT_ERROR, _CRT_WIDE(__FILE__), __LINE__,
_CRT_WIDE(QT_VERSION_STR),
reinterpret_cast<const wchar_t *> (
QString::fromLatin1(msg).utf16()));
emergency_bufL);
if (ret == 1)
_CrtDbgBreak();
#endif
@ -729,12 +751,17 @@ void qt_message_output(QtMsgType msgType, const QMessageLogContext &context, con
&& qEnvironmentVariableIsSet("QT_FATAL_WARNINGS")) ) {
#if defined(Q_CC_MSVC) && defined(QT_DEBUG) && defined(_DEBUG) && defined(_CRT_ERROR)
wchar_t contextFileL[256];
// we probably should let the compiler do this for us, by
// declaring QMessageLogContext::file to be const wchar_t * in
// the first place, but the #ifdefery above is very complex
// and we wouldn't be able to change it later on...
convert_to_wchar_t_elided(contextFileL, sizeof contextFileL / sizeof *contextFileL, context.file);
// get the current report mode
int reportMode = _CrtSetReportMode(_CRT_ERROR, _CRTDBG_MODE_WNDW);
_CrtSetReportMode(_CRT_ERROR, reportMode);
int ret = _CrtDbgReportW(_CRT_ERROR, reinterpret_cast<const wchar_t *> (
QString::fromLatin1(context.file).utf16()),
int ret = _CrtDbgReportW(_CRT_ERROR, contextFileL,
context.line, _CRT_WIDE(QT_VERSION_STR),
reinterpret_cast<const wchar_t *> (
message.utf16()));