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/*
* nosh - noshell
* a 2-hour C shell for POSIX mates
*
* czjstmax <jstmaxlol at disroot dot org>
*
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <signal.h>
#include <stdbool.h>
#include <wordexp.h>
#include <sys/wait.h>
//
void handlecc(int sig);
void freeStuff();
//
char *line = NULL;
size_t len = 0;
wordexp_t p;
int main(void)
{
signal(SIGINT, handlecc);
while (true) {
printf("$ ");
getline(&line, &len, stdin);
line[strcspn(line, "\n")] = '\0';
wordexp(line, &p, 0);
// debug
// for (size_t i = 0; i < p.we_wordc; i++) {
// printf("argv[%zu] = %s\n", i, p.we_wordv[i]);
// }
if (strlen(line) == 0)
continue; //otherwise.. SIGSEGV!
if (strcmp(p.we_wordv[0], ":q") == 0 || strcmp(p.we_wordv[0], "exit") == 0) {
freeStuff();
return 0;
}
else if (strcmp(p.we_wordv[0], "echo") == 0) {
for (size_t i = 1; i < p.we_wordc; i++)
printf("%s ", p.we_wordv[i]);
if (p.we_wordc >= 2) {
if (strcmp(p.we_wordv[1], "-c") == 0)
continue;
printf("\n");
}
}
else if (strcmp(p.we_wordv[0], "cd") == 0) {
if (chdir(p.we_wordv[1]))
perror("nsh! ERROR: failed to change directory");
}
else if (strcmp(p.we_wordv[0], "clear") == 0) {
printf("\033[2J\033[H\033[3J");
fflush(stdout);
}
else {
pid_t pid = fork();
char **argv = p.we_wordv; // pray with me now
if (pid == 0) {
char path[strlen("/usr/bin/") + strlen(p.we_wordv[0]) + 1];
sprintf(path, "/usr/bin/%s", p.we_wordv[0]);
execv(path, argv);
perror("nsh! ERROR: failed to execv()");
_exit(1);
}
else if (pid > 0) {
int status;
waitpid(pid, &status, 0);
}
else {
printf("nsh! couldn't open %s", p.we_wordv[0]);
}
}
}
}
void handlecc(int sig)
{
printf("\nnsh! %d caught.\nfreeing stuff before quitting.\n", sig);
freeStuff();
exit(0);
}
void freeStuff()
{
wordfree(&p);
free(line);
}
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