int cleanup_nodes(node *n) {
if(n != NULL) {
free(n->datum);
if(n->args != NULL) {
for(int i = 0; n->args[i] != NULL; i++) {
free(n->args[i]);
}
free(n->args);
}
cleanup_nodes(n->next);
}
free(n);
}
//-----------------------------------------------------------------------------
// Main... process command line parameters, and then setup our listening
// sockets and event loop.
int main(int argc, char **argv)
{
system_data_t sysdata;
///============================================================================
/// Initialization.
///============================================================================
init_sysdata(&sysdata);
init_settings(&sysdata);
get_options(sysdata.settings, argc, argv);
init_maxconns(&sysdata);
init_daemon(&sysdata);
init_events(&sysdata);
init_logging(&sysdata);
logger(sysdata.logging, 1, "System starting up");
init_signals(&sysdata);
init_buffers(&sysdata);
init_servers(&sysdata);
init_stats(&sysdata);
init_risp(&sysdata);
init_nodes(&sysdata);
init_msglist(&sysdata);
init_queues(&sysdata);
init_controllers(&sysdata);
///============================================================================
/// Main Event Loop.
///============================================================================
// enter the event loop.
logger(sysdata.logging, 1, "Starting Event Loop");
assert(sysdata.evbase);
event_base_loop(sysdata.evbase, 0);
logger(sysdata.logging, 1, "Shutdown preparations complete. Shutting down now.");
///============================================================================
/// Shutdown
///============================================================================
cleanup_events(&sysdata);
cleanup_controllers(&sysdata);
cleanup_queues(&sysdata);
cleanup_msglist(&sysdata);
cleanup_nodes(&sysdata);
cleanup_risp(&sysdata);
cleanup_stats(&sysdata);
cleanup_servers(&sysdata);
cleanup_buffers(&sysdata);
cleanup_signals(&sysdata);
logger(sysdata.logging, 1, "Shutdown complete.\n");
cleanup_logging(&sysdata);
cleanup_daemon(&sysdata);
cleanup_maxconns(&sysdata);
cleanup_settings(&sysdata);
cleanup_sysdata(&sysdata);
// good-bye.
return 0;
}
int main(int argc, char** argv) {
char* bucket;
int bucket_read = 0;
int bucket_size = 256;
int arg_c = 0;
int args_size = 256;
node *head = NULL;
node *cur = NULL;
//initialize with prompt
char *prompt;
if(argc >= 2)
prompt = argv[1];
else
prompt = "myshell:";
//parsing section
bucket = (char *) safe_malloc(bucket_size*sizeof(char), "fatal error in main: bucket could not be malloced");
while(1) {
printf("\n%s", prompt);
char c;
cur = create_node();
while((c = getchar())) {
if(c == EOF) {
cleanup_nodes(head);
free(cur);
free(bucket);
exit(0);
}
if(isalnum(c) || c >= 33 && c <=37 || c >=39 && c <= 47 || c >= 91 && c <= 96 || c == 123 || c == 125 || c == 126) {
bucket = (char *) chksize(bucket, bucket_read, &bucket_size, bucket_size*2+1);
bucket[bucket_read] = c;
bucket_read += 1;
} else if (c == SPACE || c == '\n'){
if(bucket_read >= 1) {
if(cur->args == NULL)
cur->args = safe_malloc(args_size*sizeof(char *), "fatal error: could not malloc args array");
cur->args[arg_c] = (char *) safe_malloc(bucket_read*sizeof(char)+2, "could not malloc datum in node");
strncpy(cur->args[arg_c], bucket, bucket_read);
cur->args[arg_c+1] = '\0';
cur->args[arg_c][bucket_read] = '\0';
bucket_read = 0;
arg_c += 1;
}
if(c == '\n') {
arg_c = 0;
if(head == NULL)
head = cur;
break;
}
} else if(memchr(cmds, c, 5)) {
if(bucket_read >= 1) {
if(cur->args == NULL)
cur->args = safe_malloc(args_size*sizeof(char *), "fatal error: could not malloc args array");
cur->args[arg_c] = (char *) safe_malloc(bucket_read*sizeof(char)+1, "could not malloc datum in node");
strncpy(cur->args[arg_c], bucket, bucket_read);
cur->args[arg_c+1] = '\0';
cur->args[arg_c][bucket_read] = '\0';
bucket_read = 0;
arg_c += 1;
}
node *next = create_node();
cur->next = next;
next->prev = cur;
next->datum = (char *) safe_malloc(2*sizeof(char), "could not malloc datum in node");
next->datum[0] = c;
next->datum[1] = '\0';
if(head == NULL)
head = cur;
cur = cur->next;
node *tmp = create_node();
cur->next = tmp;
tmp->prev = cur;
cur = tmp;
arg_c = 0;
}
}
cur=head;
if(head != NULL && head->args != NULL && strstr(head->args[0], "exit")) {
cleanup_nodes(head);
free(cur);
free(bucket);
exit(0);
}
cur = head;
//arguments section
int pid, status;
while(cur != NULL) {
int AMPERSAND = 0;
//start command states:
if(cur->datum != NULL && cur->datum[0] == '&'){
AMPERSAND = WNOHANG;
node *tmp = cur->prev;
if(cur->next != NULL && cur->next->datum != NULL || cur->next->args != NULL){
tmp->next = cur->next;
cur->next->prev = tmp;
} else {
tmp->next = NULL;
free(cur->next);
}
free(cur->datum);
free(cur->args);
free(cur);
cur = tmp;
}
if(cur->args != NULL && cur->args[0] != NULL && strstr(cur->args[0], "cd")) { //cd as a builtin command
if(chdir(cur->args[1]) != 0) {
perror("changing directory failed: invalid path");
}
} else if(cur != NULL && cur->datum != NULL && cur->datum[0] == '|') { //pipe
cur = pipline(cur->prev);
} else if (cur != NULL && cur->datum != NULL && cur->datum[0] == '>') { //redirect output
if((pid = fork()) == -1)
perror("could not fork in output redirecton");
if(pid == 0) { //child
char **args = cur->prev->args;
if(cur->next->datum == NULL && cur->next->args == NULL) { //handle >> command
cur = cur->next->next->next; //advance the args list past the second >
cur->fd[1] = -1;
cur->fd[0] = -1;
if((cur->fd[1] = open(cur->args[0], O_RDWR | O_CREAT | O_APPEND, 0666)) < 0)
perror("could not open fd in input redirection");
} else {
cur = cur->next;
cur->fd[1] = -1;
cur->fd[0] = -1;
if((cur->fd[1] = open(cur->args[0], O_RDWR | O_CREAT, 0666)) < 0)
perror("could not open fd in input redirection");
}
if(dup2(cur->fd[1], STDOUT_FILENO) < 0) {
perror("fatal error: dup2 failed in file redirection");
}
if(close(cur->fd[1]) < 0) {
perror("close operation in redirection failed");
}
execvp(args[0], args);
perror("");
} else {
if(cur != NULL && cur->next->datum != NULL && cur->next->datum[0] == '>')
cur = cur->next; //advance the args list past the second >
cur = cur->next;
waitpid(-1, &status, AMPERSAND);
}
//redirect file
} else if (cur != NULL && cur->datum != NULL && cur->datum[0] == '<') {
if((pid = fork()) == -1)
perror("could not fork in file redirecton");
if(pid == 0) { //child
cur->next->fd[1] = -1;
cur->next->fd[0] = -1;
char* arg = cur->prev->datum;
if((cur->next->fd[0] = open(cur->next->args[0], O_RDONLY)) < 0){
perror("could not open fd in input redirection");
} else {
if(dup2(cur->next->fd[0], STDIN_FILENO) == -1) {
perror("fatal error: dup2 failed in file redirection");
}
if(close(cur->next->fd[0]) < 0) {
perror("close operation in redirection failed");
}
execvp(cur->prev->args[0], cur->prev->args);
perror("");
}
} else { //parent
cur = cur->next;
waitpid(-1, &status, AMPERSAND);
}
} else if (AMPERSAND || cur->next == NULL || cur->datum != NULL && cur->datum[0] ==';') {
if((pid = fork()) == -1)
perror("could not fork in run command");
if(pid == 0) { //child
if(cur->datum != NULL && cur->datum[0] == ';')
cur = cur->prev;
execvp(cur->args[0], cur->args);
perror("");
} else {
if(AMPERSAND) {
if(cur->next != NULL && cur->next->datum != NULL && cur->next->datum[0] == ';')
cur = cur->next;
}
waitpid(-1, &status, AMPERSAND);
}
}
if(cur != NULL)
cur = cur->next;
} //while cur !NULL
cleanup_nodes(head);
head = NULL;
cur = NULL;
for(int i = 0; i < bucket_size; i++) { bucket[i] = '\0';}
arg_c = 0;
} //while 1
free(bucket);
return 0;
}
