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#include <init/shell.h>
#include <init/stdlib.h>
#include <init/tests/main.h>
#include <shared/syscalls.h>
#include <stdbool.h>
static char *split(char *base) {
while (*base) {
if (*base == ' ' || *base == '\t') {
*base++ = '\0';
return base;
}
base++;
}
return NULL;
}
static int readline(char *buf, size_t max) {
char c;
size_t pos = 0;
while (file_read(&__stdin, &c, 1)) {
switch (c) {
case '\b':
case 0x7f:
/* for some reason backspace outputs 0x7f (DEL) */
if (pos != 0) {
printf("\b \b");
pos--;
}
break;
case '\n':
case '\r':
printf("\n");
buf[pos++] = '\0';
return pos;
default:
if (pos < max) {
printf("%c", c);
buf[pos] = c;
pos++;
}
}
}
return -1; // error
}
static void cmd_cat_ls(const char *args, bool ls) {
libc_file file;
static char buf[512];
int len; // first used for strlen(args), then length of buffer
if (!args) args = "/";
len = strlen(args);
memcpy(buf, args, len + 1); // no overflow check - the shell is just a PoC
if (ls) { // paths to directories always have a trailing slash
char *p = buf;
while (*p) p++;
if (p[-1] != '/') {
p[0] = '/';
p[1] = '\0';
len++;
}
}
if (file_open(&file, buf) < 0) {
printf("couldn't open.\n");
return;
}
while (!file.eof) {
int len = file_read(&file, buf, sizeof buf);
if (len <= 0) break;
if (ls) {
for (int i = 0; i < len; i++)
if (buf[i] == '\0') buf[i] = '\n';
}
file_write(&__stdout, buf, len);
}
file_close(&file);
}
static void cmd_hexdump(const char *args) {
static uint8_t buf[512];
int fd, len;
fd = _syscall_open(args, strlen(args));
if (fd < 0) {
printf("couldn't open.\n");
return;
}
len = _syscall_read(fd, buf, sizeof buf, 0);
for (int i = 0; i < len; i += 16) {
printf("%08x ", i);
for (int j = i; j < i + 8 && j < len; j++)
printf("%02x ", buf[j]);
printf(" ");
for (int j = i + 8; j < i + 16 && j < len; j++)
printf("%02x ", buf[j]);
printf(" |");
for (int j = i; j < i + 16 && j < len; j++) {
char c = '.';
if (0x20 <= buf[j] && buf[j] < 0x7f) c = buf[j];
printf("%c", c);
}
printf("|\n");
}
_syscall_close(fd);
}
void shell_loop(void) {
static char cmd[256];
int level = 0;
char *args;
for (;;) {
printf("%x$ ", level);
readline(cmd, 256);
args = split(cmd);
if (!strcmp(cmd, "echo")) {
printf("%s\n", args);
} else if (!strcmp(cmd, "cat")) {
cmd_cat_ls(args, false);
} else if (!strcmp(cmd, "ls")) {
cmd_cat_ls(args, true);
} else if (!strcmp(cmd, "hexdump")) {
cmd_hexdump(args);
} else if (!strcmp(cmd, "catall")) {
const char *files[] = {
"/init/fake.txt",
"/init/1.txt", "/init/2.txt",
"/init/dir/3.txt", NULL};
for (int i = 0; files[i]; i++) {
printf("%s:\n", files[i]);
cmd_cat_ls(files[i], false);
printf("\n");
}
} else if (!strcmp(cmd, "shadow")) {
_syscall_mount(-1, args, strlen(args));
} else if (!strcmp(cmd, "exit")) {
_syscall_exit(0);
} else if (!strcmp(cmd, "fork")) {
if (_syscall_fork(0, NULL))
_syscall_await();
else level++;
} else if (!strcmp(cmd, "run_tests")) {
test_all();
} else {
printf("unknown command :(\n");
}
}
}
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