Centralise handling & ignoring of SIGPIPE in qcore_unix_p.h

We had two instances of this function in the Qt source code, one clearly
a copy of the other, so both had the same thread-safety issue. Instead,
let's have one copy and have both write_nosignal() and sendto() call
them.

Q_NO_POSIX_SIGNALS is also gone. It was only used with Symbian.

Change-Id: I0f1354a8e9df8e6b10a02f86a940e3c6d1222087
Reviewed-by: Peter Hartmann <phartmann@rim.com>
Reviewed-by: Shane Kearns <shane.kearns@accenture.com>
This commit is contained in:
Thiago Macieira 2012-09-11 15:53:17 +02:00 committed by The Qt Project
parent eb42be700a
commit cb7d64170d
4 changed files with 28 additions and 46 deletions

View File

@ -949,27 +949,9 @@ qint64 QProcessPrivate::readFromStderr(char *data, qint64 maxlen)
return bytesRead;
}
static void qt_ignore_sigpipe()
{
// Set to ignore SIGPIPE once only.
static QBasicAtomicInt atom = Q_BASIC_ATOMIC_INITIALIZER(0);
if (!atom.load()) {
// More than one thread could turn off SIGPIPE at the same time
// But that's acceptable because they all would be doing the same
// action
struct sigaction noaction;
memset(&noaction, 0, sizeof(noaction));
noaction.sa_handler = SIG_IGN;
::sigaction(SIGPIPE, &noaction, 0);
atom.store(1);
}
}
qint64 QProcessPrivate::writeToStdin(const char *data, qint64 maxlen)
{
qt_ignore_sigpipe();
qint64 written = qt_safe_write(stdinChannel.pipe[1], data, maxlen);
qint64 written = qt_safe_write_nosignal(stdinChannel.pipe[1], data, maxlen);
#if defined QPROCESS_DEBUG
qDebug("QProcessPrivate::writeToStdin(%p \"%s\", %lld) == %lld",
data, qt_prettyDebug(data, maxlen, 16).constData(), maxlen, written);

View File

@ -54,11 +54,13 @@
//
#include "qplatformdefs.h"
#include "qatomic.h"
#ifndef Q_OS_UNIX
# error "qcore_unix_p.h included on a non-Unix system"
#endif
#include <string.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>
@ -143,6 +145,22 @@ inline timeval operator*(const timeval &t1, int mul)
return normalizedTimeval(tmp);
}
inline void qt_ignore_sigpipe()
{
// Set to ignore SIGPIPE once only.
static QBasicAtomicInt atom = Q_BASIC_ATOMIC_INITIALIZER(0);
if (!atom.load()) {
// More than one thread could turn off SIGPIPE at the same time
// But that's acceptable because they all would be doing the same
// action
struct sigaction noaction;
memset(&noaction, 0, sizeof(noaction));
noaction.sa_handler = SIG_IGN;
::sigaction(SIGPIPE, &noaction, 0);
atom.store(1);
}
}
// don't call QT_OPEN or ::open
// call qt_safe_open
static inline int qt_safe_open(const char *pathname, int flags, mode_t mode = 0777)
@ -265,6 +283,12 @@ static inline qint64 qt_safe_write(int fd, const void *data, qint64 len)
#undef QT_WRITE
#define QT_WRITE qt_safe_write
static inline qint64 qt_safe_write_nosignal(int fd, const void *data, qint64 len)
{
qt_ignore_sigpipe();
return qt_safe_write(fd, data, len);
}
static inline int qt_safe_close(int fd)
{
register int ret;

View File

@ -98,27 +98,6 @@ static QByteArray qt_prettyDebug(const char *data, int len, int maxSize)
}
#endif
static void qt_ignore_sigpipe()
{
#ifndef Q_NO_POSIX_SIGNALS
// Set to ignore SIGPIPE once only.
static QBasicAtomicInt atom = Q_BASIC_ATOMIC_INITIALIZER(0);
if (!atom.load()) {
// More than one thread could turn off SIGPIPE at the same time
// But that's acceptable because they all would be doing the same
// action
struct sigaction noaction;
memset(&noaction, 0, sizeof(noaction));
noaction.sa_handler = SIG_IGN;
::sigaction(SIGPIPE, &noaction, 0);
atom.store(1);
}
#else
// Posix signals are not supported by the underlying platform
// so we don't need to ignore sigpipe signal explicitly
#endif
}
/*
Extracts the port and address from a sockaddr, and stores them in
\a port and \a addr if they are non-null.
@ -900,8 +879,6 @@ qint64 QNativeSocketEnginePrivate::nativeSendDatagram(const char *data, qint64 l
sockAddrPtr = (struct sockaddr *)&sockAddrIPv4;
}
// ignore the SIGPIPE signal
qt_ignore_sigpipe();
ssize_t sentBytes = qt_safe_sendto(socketDescriptor, data, len,
0, sockAddrPtr, sockAddrSize);
@ -1025,11 +1002,8 @@ qint64 QNativeSocketEnginePrivate::nativeWrite(const char *data, qint64 len)
{
Q_Q(QNativeSocketEngine);
// ignore the SIGPIPE signal
qt_ignore_sigpipe();
ssize_t writtenBytes;
writtenBytes = qt_safe_write(socketDescriptor, data, len);
writtenBytes = qt_safe_write_nosignal(socketDescriptor, data, len);
if (writtenBytes < 0) {
switch (errno) {

View File

@ -188,6 +188,8 @@ static inline int qt_safe_sendto(int sockfd, const void *buf, size_t len, int fl
{
#ifdef MSG_NOSIGNAL
flags |= MSG_NOSIGNAL;
#else
qt_ignore_sigpipe();
#endif
register int ret;