From 75a2c81b0041df4ca59178cf52d9e5a8815f3524 Mon Sep 17 00:00:00 2001 From: Thiago Macieira Date: Thu, 24 Jul 2014 12:59:14 -0700 Subject: Handle posix_spawn using exit code 127 to indicate fail-to-start Most posix_spawn implementations are done using fork(), so the only way to report errors afer fork() is via a special exit code. Reference: http://pubs.opengroup.org/onlinepubs/009695399/functions/posix_spawn.html Change-Id: I3a37f81b0cb278bb31e5cb83c87e6b4c034dbc19 Reviewed-by: Thiago Macieira --- src/corelib/io/qprocess.cpp | 18 ++++++++++++++++-- 1 file changed, 16 insertions(+), 2 deletions(-) (limited to 'src/corelib/io') diff --git a/src/corelib/io/qprocess.cpp b/src/corelib/io/qprocess.cpp index 976d8503f3..a7d521fc6c 100644 --- a/src/corelib/io/qprocess.cpp +++ b/src/corelib/io/qprocess.cpp @@ -1078,6 +1078,17 @@ bool QProcessPrivate::_q_processDied() processError = QProcess::Crashed; q->setErrorString(QProcess::tr("Process crashed")); emit q->error(processError); + } else { +#ifdef QPROCESS_USE_SPAWN + // if we're using posix_spawn, waitForStarted always succeeds. + // POSIX documents that the sub-process launched by posix_spawn will exit with code + // 127 if anything prevents the target program from starting. + // http://pubs.opengroup.org/onlinepubs/009695399/functions/posix_spawn.html + if (exitStatus == QProcess::NormalExit && exitCode == 127) { + processError = QProcess::FailedToStart; + q->setErrorString(QProcess::tr("Process failed to start (spawned process exited with code 127)")); + } +#endif } bool wasRunning = (processState == QProcess::Running); @@ -1753,6 +1764,9 @@ QProcessEnvironment QProcess::processEnvironment() const If msecs is -1, this function will not time out. + \note On some UNIX operating systems, this function may return true but + the process may later report a QProcess::FailedToStart error. + \sa started(), waitForReadyRead(), waitForBytesWritten(), waitForFinished() */ bool QProcess::waitForStarted(int msecs) @@ -2347,7 +2361,7 @@ int QProcess::execute(const QString &program, const QStringList &arguments) QProcess process; process.setReadChannelMode(ForwardedChannels); process.start(program, arguments); - if (!process.waitForFinished(-1)) + if (!process.waitForFinished(-1) || process.error() == FailedToStart) return -2; return process.exitStatus() == QProcess::NormalExit ? process.exitCode() : -1; } @@ -2370,7 +2384,7 @@ int QProcess::execute(const QString &command) QProcess process; process.setReadChannelMode(ForwardedChannels); process.start(command); - if (!process.waitForFinished(-1)) + if (!process.waitForFinished(-1) || process.error() == FailedToStart) return -2; return process.exitStatus() == QProcess::NormalExit ? process.exitCode() : -1; } -- cgit v1.2.3