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#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <fcntl.h>
#include <signal.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <unistd.h>
#include "array.h"
#include "errno.h"
#include <stdbool.h>
void print_prompt();
// returns the return code of the executed program
int exec_command(const char *path, char *const argv[], unsigned timeout);
int main(int argc, char* argv[]) {
char *argument;
char **arguments;
if (arrayInit(argument) != 0 || arrayInit(arguments) != 0) {
fprintf(stderr, "Failed to prepare new argument array");
exit(-1);
}
while (true) {
char *command = NULL;
size_t cap = 0;
size_t length = 0;
print_prompt();
if ((length = getline(&command, &cap, stdin)) < 0) {
fprintf(stderr, "Failed to read from STDIN");
exit(-1);
}
command[length - 1] = '\0'; // cut the line feed
/*
char c;
int i = 0;
while (true) {
c = command[i++];
if (c == ' ') {
arrayPush(argument) = '\0';
arrayPush(arguments) = argument;
printf("+ %s\n", argument);
arrayRelease(argument);
arrayInit(argument);
} else if (c == '\0') {
} else {
arrayPush(argument) = c;
}
}
*/
if (strstr(command, "cd") != NULL) {
printf("Changing dirs \n");
chdir("beispiele");
} else if (strcmp(command, "exit\n") == 0) {
exit(0);
} else {
exec_command(command, (char *const []) {command, NULL}, 0);
}
free((void *)command);
}
}
void print_prompt() {
size_t length = 1024;
char *buffer = malloc(length * sizeof(char));
getcwd(buffer, length);
if (buffer == NULL) {
printf(".> ");
} else {
printf("%s > ", buffer);
}
}
int exec_command(const char *path, char *const argv[], unsigned timeout) {
int pid;
int pipefd[2];
int status;
char buf[512];
pipe(pipefd);
if ((pid = fork()) == 0) {
close(pipefd[0]);
dup2(pipefd[1], 1); // includes close(1);
close(pipefd[1]);
execvp(path, argv);
fprintf(stderr, "no program\n");
exit(-1);
}
if (pid < 0) {
fprintf(stderr, "no fork\n");
exit(-2);
}
close(pipefd[1]);
size_t length = 0;
if ((length = read(pipefd[0], buf, 512)) <= 0) {
fprintf(stderr, "error\n");
exit(-3);
}
waitpid(pid, &status, 0);
close(pipefd[0]);
buf[length] = '\0';
printf("%s", buf);
return WEXITSTATUS(status);
}
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