QWidget* createEnvs(QWidget* parent) {
parent->setObjectName("envs1");
QGridLayout* grid = new QGridLayout(parent);
grid->addWidget(createEnv(new QGroupBox(), 0), 0, 0);
grid->addWidget(createEnv(new QGroupBox(), 1), 0, 1);
grid->addWidget(createEnv(new QGroupBox(), 2), 0, 2);
grid->addWidget(createEnv(new QGroupBox(), 3), 0, 3);
grid->setRowStretch(1, 1);
grid->setHorizontalSpacing(5);
return parent;
}
//this function handles simple commands of cd, dirs, wait and the built ins
//parameters are the command list and the boolean of if the command is
//backgrounded
//returns
int simple(CMD *cmdList, bool bkgd){
pid_t pid, wpid;
int status;
//if the command is cd to move directories
if(strcmp(cmdList->argv[0], "cd") == 0){
int ret = 0;
if(cmdList->argc == 2) {
ret = chdir(cmdList->argv[1]);
} else if(cmdList->argc == 1){
ret = chdir(getenv("HOME"));
} else {
//incorrect number of arguments
perror("usage");
}
if (ret != 0) {
//problem with chdir
perror("chdir error");
}
//is if command is dirs command to print path to directory
} else if(strcmp(cmdList->argv[0], "dirs") == 0) {
char cwd[PATH_MAX];
if (getcwd(cwd, sizeof(cwd)) != NULL && cmdList->argc == 1){
printf( "%s\n", cwd);
} else {
//incorrect number of arguments
perror("usage");
}
//if command is to wait which means wait for previous processes to
//terminate
}else if(strcmp(cmdList->argv[0], "wait") == 0){
if(cmdList->argc != 1) perror("usage");
int status;
pid_t waiting;
//reap the zombies
while ((waiting = wait (&status)) > 0 )
fprintf(stderr, "Completed: %d (%d)\n",waiting, status);
}else {
pid = fork();
if (pid == 0) {
//Child Process
//start at the bottom of the function table
createEnv(cmdList);
//set file descriptors if necessary
int saved_stdout = NULL;
int saved_stdin = NULL;
int dupsval = dups(cmdList, &saved_stdout, &saved_stdin);
if(dupsval != -1) exit(EXIT_FAILURE);
//check return of exec
if (execvp(cmdList->argv[0], cmdList->argv) == -1) {
perror("execvp");
}
//reset file descriptors
resetDups(cmdList, &saved_stdout, &saved_stdin);
exit(EXIT_FAILURE);
} else if (pid < 0) {
// Error forking
perror("fork");
} else if(!bkgd){
// Parent process that is only done if not backgrounded
do {
//pointer to wait
wpid = waitpid(pid, &status, WUNTRACED);
// fprintf(stderr, "status %d wpid %d \n", status, wpid);
} while (!WIFEXITED(status) && !WIFSIGNALED(status));
int wistat = setStatus(status);
return wistat;
} else if(bkgd) fprintf(stderr, "Backgrounded: %d\n", pid);
}
return 0;
}