ProcessHandleImpl* ProcessImpl::launchImpl(const std::string& command, const ArgsImpl& args, const std::string& initialDirectory, Pipe* inPipe, Pipe* outPipe, Pipe* errPipe, const EnvImpl& env)
{
#if defined(__QNX__)
if (initialDirectory.empty())
{
/// use QNX's spawn system call which is more efficient than fork/exec.
char** argv = new char*[args.size() + 2];
int i = 0;
argv[i++] = const_cast<char*>(command.c_str());
for (ArgsImpl::const_iterator it = args.begin(); it != args.end(); ++it)
argv[i++] = const_cast<char*>(it->c_str());
argv[i] = NULL;
struct inheritance inherit;
std::memset(&inherit, 0, sizeof(inherit));
inherit.flags = SPAWN_ALIGN_DEFAULT | SPAWN_CHECK_SCRIPT | SPAWN_SEARCH_PATH;
int fdmap[3];
fdmap[0] = inPipe ? inPipe->readHandle() : 0;
fdmap[1] = outPipe ? outPipe->writeHandle() : 1;
fdmap[2] = errPipe ? errPipe->writeHandle() : 2;
char** envPtr = 0;
std::vector<char> envChars;
std::vector<char*> envPtrs;
if (!env.empty())
{
envChars = getEnvironmentVariablesBuffer(env);
envPtrs.reserve(env.size() + 1);
char* p = &envChars[0];
while (*p)
{
envPtrs.push_back(p);
while (*p) ++p;
++p;
}
envPtrs.push_back(0);
envPtr = &envPtrs[0];
}
int pid = spawn(command.c_str(), 3, fdmap, &inherit, argv, envPtr);
delete [] argv;
if (pid == -1)
throw SystemException("cannot spawn", command);
if (inPipe) inPipe->close(Pipe::CLOSE_READ);
if (outPipe) outPipe->close(Pipe::CLOSE_WRITE);
if (errPipe) errPipe->close(Pipe::CLOSE_WRITE);
return new ProcessHandleImpl(pid);
}
else
{
return launchByForkExecImpl(command, args, initialDirectory, inPipe, outPipe, errPipe, env);
}
#else
return launchByForkExecImpl(command, args, initialDirectory, inPipe, outPipe, errPipe, env);
#endif
}
ProcessHandleImpl* ProcessImpl::launchByForkExecImpl(const std::string& command, const ArgsImpl& args, const std::string& initialDirectory, Pipe* inPipe, Pipe* outPipe, Pipe* errPipe, const EnvImpl& env)
{
int pid = fork();
if (pid < 0)
{
throw SystemException("Cannot fork process for", command);
}
else if (pid == 0)
{
if (!initialDirectory.empty())
{
if (chdir(initialDirectory.c_str()) != 0)
{
_exit(72);
}
}
setEnvironmentVariables(env);
// setup redirection
if (inPipe)
{
dup2(inPipe->readHandle(), STDIN_FILENO);
inPipe->close(Pipe::CLOSE_BOTH);
}
// outPipe and errPipe may be the same, so we dup first and close later
if (outPipe) dup2(outPipe->writeHandle(), STDOUT_FILENO);
if (errPipe) dup2(errPipe->writeHandle(), STDERR_FILENO);
if (outPipe) outPipe->close(Pipe::CLOSE_BOTH);
if (errPipe) errPipe->close(Pipe::CLOSE_BOTH);
// close all open file descriptors other than stdin, stdout, stderr
for (int i = 3; i < getdtablesize(); ++i)
close(i);
char** argv = new char*[args.size() + 2];
int i = 0;
argv[i++] = const_cast<char*>(command.c_str());
for (ArgsImpl::const_iterator it = args.begin(); it != args.end(); ++it)
argv[i++] = const_cast<char*>(it->c_str());
argv[i] = NULL;
execvp(command.c_str(), argv);
_exit(72);
}
if (inPipe) inPipe->close(Pipe::CLOSE_READ);
if (outPipe) outPipe->close(Pipe::CLOSE_WRITE);
if (errPipe) errPipe->close(Pipe::CLOSE_WRITE);
return new ProcessHandleImpl(pid);
}
ProcessHandleImpl* ProcessImpl::launchImpl(const std::string& command, const ArgsImpl& args, const std::string& initialDirectory, Pipe* inPipe, Pipe* outPipe, Pipe* errPipe, const EnvImpl& env)
{
char** argv = new char*[args.size() + 2];
int i = 0;
argv[i++] = const_cast<char*>(command.c_str());
for (ArgsImpl::const_iterator it = args.begin(); it != args.end(); ++it)
argv[i++] = const_cast<char*>(it->c_str());
argv[i] = NULL;
try
{
int pid = vfork();
if (pid < 0)
{
throw SystemException("Cannot fork process for", command);
}
else if (pid == 0)
{
if (!initialDirectory.empty())
{
if (chdir(initialDirectory.c_str()) != 0)
{
std::stringstream str;
str << "Cannot set initial directory to '" << initialDirectory << "' when forking process for";
throw SystemException(str.str(), command);
}
}
setEnvironmentVariables(environment_variables);
if (execvp(command.c_str(), argv) == -1)
throw SystemException("Cannot execute command", command);
}
else
{
delete [] argv;
return new ProcessHandleImpl(pid);
}
}
catch (...)
{
delete [] argv;
throw;
}
}