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/* noshmore
* an extended version of nosh,
* the minimal POSIX C shell.
* -> generally: adds some functionality.
*
* von 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>
#include <readline/readline.h>
#include <readline/history.h>
void handlecc(int sig);
void FreeAll();
char *line = NULL;
wordexp_t p;
int main(void)
{
signal(SIGINT, handlecc);
char *USER = getenv("USER");
if (!USER)
USER = "god";
while (true) {
char prompt[strlen(USER) + strlen("$ ") + 1];
snprintf(prompt, sizeof(prompt), "%s$ ", USER);
line = readline(prompt);
if (!line)
break;
if (*line)
add_history(line);
if (wordexp(line, &p, 0) != 0) {
fprintf(stderr, "nsh+! parse error\n");
free(line);
continue;
}
// built-ins
if (p.we_wordc == 0) {
FreeAll();
continue;
}
if (strcmp(p.we_wordv[0], ":q") == 0 || strcmp(p.we_wordv[0], "exit") == 0) {
FreeAll();
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)
printf("\n");
else continue;
}
}
else if (strcmp(p.we_wordv[0], "cd") == 0) {
if (p.we_wordc <= 1) {
printf("nsh+! cd: no arguments were given.\n");
FreeAll();
continue;
}
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 if (strcmp(p.we_wordv[0], "help") == 0) {
printf(
"noshmore\n"
"an extended version of nosh, the minimal POSIX C shell.\n"
"\n"
"built-ins:\n"
"echo -> outputs a string of text, doesn't need \" enclosure.\n"
" supports '-c' for output without '\\n'"
"clear -> clears screen (and scrollback)\n"
"cd -> change working directory\n"
"help -> prints this screen\n"
"\ngithub repo: github.com/jstmaxlol/noshmore\n"
);
}
else {
pid_t pid = fork();
char **argv = p.we_wordv; // pray with me now
if (pid == 0) {
execvp(p.we_wordv[0], argv);
perror("nsh+! ERROR: failed to execvp()");
FreeAll();
_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);
FreeAll();
exit(0);
}
void FreeAll()
{
wordfree(&p);
free(line);
line = NULL;
}
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