msh-console/shell.cpp

#include "shell.h"

string Shell::getPs() const
{
    return ps;
}

void Shell::setPs(const string &value)
{
    ps = value;
}

string Shell::getName() const
{
    return name;
}

void Shell::setName(const string &value)
{
    name = value;
}

Shell::Shell( string n, string ps,void (*s)(Shell*)) : cmds(this)
{
    shellSetup = s;
    name = n;
    this->ps = ps;
    notLoop = false;
}

void Shell::launch(){
  //launch setup
  if(notLoop) {
      throw ShellLaunchInSetupException();
      return;
  }
  if(shellSetup!=0) {
      notLoop = true;
      (*shellSetup)(this);
      notLoop = false;
  }
  //launch loop
  string* line;
  vector<string>* args;
  int status;
  do {
    bool readSuccess;
    do{
        cout << ps << " ";
        try{
            line = read_line();
            readSuccess = true;
        }
        catch (IsUndoingLineException){
            cout << "\n";
            readSuccess = false;
        }
    }while(!readSuccess);
    args = split_line(line);
    status = executeCmd(args);
    delete args;
  } while (status);
}

int Shell::launchCmd(vector<string>* args)
{
    int status;

    pid_t pid = fork();
    if (pid == 0) {
        //child process

        //execute threadCommand
        int a;
        try {
            a=cmds.launch(args, true);
        }
        catch (CommandNotFoundException){
            //execute bash command or program
            vector<char *> argv(args->size() + 1);
            size_t i;
            for (i = 0; i != args->size()-1; ++i)
            {
                argv[i] = &(args->operator[](i)[0]);
            }
            argv[i] = NULL;
            if((a=execvp(argv[0], argv.data())) == -1) {
                cerr << name <<": command " << args->operator [](0) << " not found\n";
            }
            exit(EXIT_FAILURE);
        }
        exit(EXIT_SUCCESS);
    }
    else if (pid < 0) {
        // Error forking
        cerr << name <<": error forking the process\n";
    }
    else {
        // Parent process
        do {
            //wait until child finished
            waitpid(pid, &status, WUNTRACED);
        } while (!WIFEXITED(status) && !WIFSIGNALED(status));
    }
    return 1;
}

int Shell::executeCmd(vector<string>* args)
{
    if (args->operator [](0) == "\0") {
        // An empty command was entered.
        return 1;
    }
    int ret;
    try {
        ret = cmds.launch(args, false);
    }
    catch(CommandNotFoundException) {
        ret = launchCmd(args);
    }
    return ret;
}

inline int Shell::executeCmd(const std::string &args){
    return executeCmd(split_line(&args));
}

void Shell::EofHandler(int){
    undoingLine = true;
}

void setEofHandler(void (*funcptr)(int)){
    struct sigaction *sa = new struct sigaction();
    sa->sa_handler = funcptr;
    sa->sa_flags = 0; // not SA_RESTART!;
    sigaction(SIGINT, sa, NULL);
    delete sa;
}

string* Shell::read_line()
{
    string* buffer = new string();
    setEofHandler(EofHandler);
    getline(cin,*buffer); // get command
    cin.clear();  // clear flags

    if(undoingLine){
        undoingLine=false;
        throw IsUndoingLineException();
    }
    return buffer;
}

vector<string>* Shell::split_line(const string* line)
{
    vector<string>* tokens = new vector<string>();
    string ln = *line;
    istringstream is(ln);
    int i;
    for(i=0; getline(is, ln, ' '); i++){
        tokens->push_back(ln);
    }
    tokens->push_back("\0");
    return tokens;
}

bool Shell::undoingLine = false;

void Shell::addCmd(Command* cmd, bool isthread){
    cmds.add(cmd, isthread);
}

size_t Shell::howManyCmds() const{
    return cmds.howMany();
}