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#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <dirent.h>
#include <unistd.h>
#define MAX_HISTORY 100
#define MAX_COMMAND_LENGTH 256
struct com_struct {
char *com;
char *arg;
};
void test() {
printf("\nprint to output");
}
// exit() command
void exit_() {
exit(0);
}
// ls command
// get the requested path and put it into a const later on when getting the user input
void ls(const char *path) {
struct dirent *entry;
DIR *dP = opendir(path);
// check if the directory got opened successfully
if (dP == NULL) {
perror("opendir");
return;
}
// print the folder|directory name
while ((entry = readdir(dP)) != NULL) {
printf("%s", entry->d_name);
}
closedir(dP);
}
// echo command
char *echo(const char *command) {
const char *argv = (char *) malloc(sizeof(char) * 4);
char *command_argument = (char *) malloc(sizeof(char) * 100);
int separation_index = 0;
for (int i = 0; i < sizeof(command); i++) {
if (strcmp(&command[i], " ") == 0) {
separation_index = i;
for (int j = 0; j < separation_index; j++) {
argv = &command[j];
}
}
}
if (strcmp(argv, "echo") == 0) {
for (int i = separation_index + 1; i < (sizeof(command) - separation_index); i++) {
if (strcmp(&command[i], "\0") != 0) {
break;
} else {
strcpy(&command_argument[i - (separation_index - 1)], &command[i]);
}
}
}
return command_argument;
}
struct com_struct split_command(char *input) {
struct com_struct NEW_COMMAND;
const char *command = strtok(input, "");
const char *argument = strtok(NULL, "\n");
NEW_COMMAND.com = command ? strdup(command) : NULL;
NEW_COMMAND.arg = command ? strdup(argument) : NULL;
return NEW_COMMAND;
}
int main(void) {
while (1) {
char *input = malloc(MAX_COMMAND_LENGTH);
// print the shell sign
printf("\n $ ");
// get the user input, store it and split it up
fgets(input, MAX_COMMAND_LENGTH, stdin);
const struct com_struct new_input = split_command(input);
if (strcmp(new_input.com, "ls") == 0) {
ls(new_input.arg);
} else if (strcmp(new_input.com, "test") == 0) {
test();
} else if (strcmp(new_input.com, "exit") == 0) {
free(input);
free(new_input.com);
free(new_input.arg);
exit_();
}
}
return 0;
}
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