/***********************************************************************
* Factory routine -- connect to server and create remote device
**********************************************************************/
static SoapySDR::Device *makeRemote(const SoapySDR::Kwargs &args)
{
if (args.count(SOAPY_REMOTE_KWARG_STOP) != 0) //probably wont happen
{
throw std::runtime_error("SoapyRemoteDevice() -- factory loop");
}
if (args.count("remote") == 0)
{
throw std::runtime_error("SoapyRemoteDevice() -- missing URL");
}
auto url = SoapyURL(args.at("remote"));
//default url parameters when not specified
if (url.getScheme().empty()) url.setScheme("tcp");
if (url.getService().empty()) url.setService(SOAPY_REMOTE_DEFAULT_SERVICE);
return new SoapyRemoteDevice(url.toString(), translateArgs(args));
}
/***********************************************************************
* Discovery routine -- connect to server when key specified
**********************************************************************/
static std::vector<SoapySDR::Kwargs> findRemote(const SoapySDR::Kwargs &args)
{
std::vector<SoapySDR::Kwargs> result;
if (args.count(SOAPY_REMOTE_KWARG_STOP) != 0) return result;
//no remote specified, use the discovery protocol
if (args.count("remote") == 0)
{
//On non-windows platforms the endpoint instance can last the
//duration of the process because it can be cleaned up safely.
//Windows has issues cleaning up threads and sockets on exit.
#ifndef _MSC_VER
static
#endif //_MSC_VER
auto ssdpEndpoint = SoapySSDPEndpoint::getInstance();
//enable forces new search queries
ssdpEndpoint->enablePeriodicSearch(true);
//wait maximum timeout for replies
std::this_thread::sleep_for(std::chrono::microseconds(SOAPY_REMOTE_SOCKET_TIMEOUT_US));
for (const auto &url : SoapySSDPEndpoint::getInstance()->getServerURLs())
{
auto argsWithURL = args;
argsWithURL["remote"] = url;
const auto subResult = findRemote(argsWithURL);
result.insert(result.end(), subResult.begin(), subResult.end());
}
return result;
}
//otherwise connect to a specific url and enumerate
auto url = SoapyURL(args.at("remote"));
//default url parameters when not specified
if (url.getScheme().empty()) url.setScheme("tcp");
if (url.getService().empty()) url.setService(SOAPY_REMOTE_DEFAULT_SERVICE);
//try to connect to the remote server
SoapySocketSession sess;
SoapyRPCSocket s;
int ret = s.connect(url.toString());
if (ret != 0)
{
SoapySDR::logf(SOAPY_SDR_ERROR, "SoapyRemote::find() -- connect(%s) FAIL: %s", url.toString().c_str(), s.lastErrorMsg());
return result;
}
//find transaction
try
{
SoapyLogAcceptor logAcceptor(url.toString(), s);
SoapyRPCPacker packer(s);
packer & SOAPY_REMOTE_FIND;
packer & translateArgs(args);
packer();
SoapyRPCUnpacker unpacker(s);
unpacker & result;
//graceful disconnect
SoapyRPCPacker packerHangup(s);
packerHangup & SOAPY_REMOTE_HANGUP;
packerHangup();
SoapyRPCUnpacker unpackerHangup(s);
}
catch (const std::exception &ex)
{
SoapySDR::logf(SOAPY_SDR_ERROR, "SoapyRemote::find() -- transact FAIL: %s", ex.what());
}
//remove instances of the stop key from the result
for (auto &resultArgs : result)
{
resultArgs.erase(SOAPY_REMOTE_KWARG_STOP);
if (resultArgs.count("driver") != 0)
{
resultArgs["remote:driver"] = resultArgs.at("driver");
resultArgs.erase("driver");
}
if (resultArgs.count("type") != 0)
{
resultArgs["remote:type"] = resultArgs.at("type");
resultArgs.erase("type");
}
resultArgs["remote"] = url.toString();
}
return result;
}
/**
* @function executeCommand
*
* @abstract Execute the command, using the given pipe as stdin.
* @discussion Loads input / output files, create pipes, and forks off children
* to execute the task.
*
* @param command - a struct representing the command
* pipe - one end of a pipe to be used as stdin, or NULL if there is none
*
* @result Returns nothing.
*/
void executeCommand(Command* command, int inPipe) {
if (strcmp(command->args->arg, "exit") == 0) {
printf("Exiting\n");
exit(0);
}
else if (strcmp(command->args->arg, "cd") == 0
|| strcmp(command->args->arg, "chdir") == 0) {
// Change directories
char* path;
if (command->args->nextArg == NULL) {
char buff[PATH_MAX];
char* username = getpwuid(getuid())->pw_name;
sprintf(buff, "/home/%s", username);
path = buff;
}
else {
path = command->args->nextArg->arg;
}
if (chdir(path) == -1) {
printf("%s\n", strerror(errno));
}
return;
}
else if (strcmp(command->args->arg, "history") == 0) {
// Print history or error as to why that cannot be done.
print_sh_history(command);
return;
}
else if (command->args->arg[0] == '!') {
// If !n is argued, rerun the n-th line in history.
rerun_cmd_n(command);
return;
}
// Create a pipe if there is a next command
int pipefd[2] = {-1, -1};
if (command->pipe_destination != NULL) {
if (pipe(pipefd) == -1) {
printf("%s\n", strerror(errno));
}
}
pid_t pid = fork();
if (pid < 0) {
printf("Fork failed!\n");
exit(1);
}
else if (pid == 0) {
char** args = translateArgs(command->args);
// Load the input and output
// Use the pipe if it exists
// (output and input take precedence over pipe)
int in_fd, out_fd;
if (inPipe > -1) {
dup2(inPipe, STDIN_FILENO);
close(inPipe);
}
else if (command->input != NULL) {
in_fd = open(command->input, O_RDONLY);
if (in_fd == -1) {
printf("Failed to open input file \n");
return;
}
dup2(in_fd, STDIN_FILENO); /* Replace stdin */
close(in_fd);
}
if (pipefd[1] > -1) {
dup2(pipefd[1], STDOUT_FILENO);
close(pipefd[1]);
}
else if (command->output != NULL) {
out_fd = open(command->output, O_CREAT | O_TRUNC | O_WRONLY,
S_IRUSR | S_IRGRP | S_IROTH);
if (out_fd == -1) {
printf("Failed to open output file \n");
return;
}
dup2(out_fd, STDOUT_FILENO); /* Replace stdout */
close(out_fd);
}
if (execvp(args[0], args) == -1) {
printf("Could not execute %s!\n", args[0]);
exit(1);
}
}
else {
// Recurse on the next command if there is one, pass along the pipe
if (inPipe > -1) {
close(inPipe);
}
if (pipefd[1] > -1) {
close(pipefd[1]);
}
if (command->pipe_destination != NULL) {
executeCommand(command->pipe_destination, pipefd[0]);
}
}
}