//matches a command executes it,
//returns whether the shell should continue running.
bool match_command(struct CommandBuffer * cb,char ** cwd,const char ** path){
bool res = true;
if(strcmp(cb->command_buffer,"exit") == 0){
res = false;
}else{
char ** buff = parse_command(cb->command_buffer);
if(strcmp(buff[0],"cd") == 0){
change_dir(buff[0],cwd);
}else{
bool found_pipe = false;
size_t pos = 0;
while(buff[pos]){
if(strcmp(buff[pos],"|") == 0){
found_pipe = true;
buff[pos] = NULL;
break;
}
++pos;
}
if(found_pipe){
res = execute_pipe(path,buff[0],&buff[0],buff[pos+1],&buff[pos+1]);
}else{
res = execute(path,buff[0],&buff[0]);
}
}
free(buff);
}
return res;
}
void
execute_command(command_t c, int profiling) {
switch (c->type) {
case IF_COMMAND:
execute_if(c, profiling);
break;
case UNTIL_COMMAND:
execute_until(c, profiling);
break;
case WHILE_COMMAND:
execute_while(c, profiling);
break;
case SEQUENCE_COMMAND:
execute_sequence(c, profiling);
break;
case PIPE_COMMAND:
execute_pipe(c, profiling);
break;
case SIMPLE_COMMAND:
execute_simple(c, profiling);
break;
case SUBSHELL_COMMAND:
execute_subshell(c, profiling);
break;
default:
error (1, 0, "command not found");
}
}
int main(void)
{
int i, background;
char input[MAX];
char path[MAX] = ".";
char entry_dir[MAX] = {0};
char working_dir[MAX] = {0};
char *arguments[512] = {0}; /* enter up to 511 arguments, one is reserved for the execution cmd */
getcwd(entry_dir, sizeof(entry_dir)); /* get the entry directory */
/* infinite loop until the user enters exit */
while (1) {
signal(SIGINT, ctrlc_handler); /* signalhandler to avoid CTRL+C killing the shell */
prompt(path);
fgets(input, MAX, stdin); /* read from standardinput */
i = 0;
while (input[i] != '\n')
i++;
input[i] = '\0'; /* remove newline from read string and replace it with \0 */
background = parse_input(input, arguments); /* parse string and set background/pipe option */
if (*arguments != 0){ /* press Enter without SEGfault :P */
/* all ifs are built-ins for the shell, except for the else */
if (strcmp(arguments[0], "exit") == 0)
return 0;
else if (background == 2) {
execute_pipe(arguments);
} else if (strcmp(arguments[0], "cd") == 0) {
if (arguments[1] == NULL) { /* change to user's HOME if only cd is entered */
chdir(getenv("HOME"));
getcwd(working_dir, sizeof(working_dir));
print_current_dir(entry_dir, working_dir, path);
} else {
chdir(arguments[1]);
getcwd(working_dir, sizeof(working_dir));
print_current_dir(entry_dir, working_dir, path);
}
} else if (strcmp(arguments[0], "wait") == 0) {
if (arguments[1] == NULL) /* maybe there is no pid given by the user */
puts("No PID!");
else {
keepWaiting = 1;
waiting(arguments);
}
} else {
execute_cmd(arguments, background);
}
}
}
}
int execute_command_type(command_t c)
{
switch(c->type){
case SIMPLE_COMMAND:
execute(c);
break;
case PIPE_COMMAND:
execute_pipe(c);
break;
case AND_COMMAND:
// the first command already fails
if(execute_command_type(c->u.command[0]) != 0){
c->status = command_status(c->u.command[0]);
}else{
c->status = execute_command_type(c->u.command[1]);
}
break;
case OR_COMMAND:
if(execute_command_type(c->u.command[0]) == 0){
c->status = 0;
}else{
// try the second command if the first fails
c->status = execute_command_type(c->u.command[1]);
}
break;
case SUBSHELL_COMMAND:
c->status = execute_command_type(c->u.subshell_command);
break;
case SEQUENCE_COMMAND: // return the status of the last command
execute_sequence(c);
break;
}
return c->status;
}
void
execute_command (command_t c, bool time_travel)
{
char cmd_type = ' ';
switch(c->type) {
case SIMPLE_COMMAND:
execute_simple(c);
cmd_type = 's';
break;
case SUBSHELL_COMMAND:
execute_subshell(c, time_travel);
cmd_type = '(';
break;
case AND_COMMAND:
execute_and(c, time_travel);
cmd_type = 'a';
break;
case OR_COMMAND:
execute_or(c, time_travel);
cmd_type = 'o';
break;
case SEQUENCE_COMMAND:
execute_sequence(c, time_travel);
cmd_type = ';';
break;
case PIPE_COMMAND:
execute_pipe(c, time_travel);
cmd_type = '|';
break;
default:
return;
}
if (DEBUG) {
printf("%c cmd - exit status: %d\n", cmd_type, c->status);
}
}
