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#include <shared/syscalls.h>
#include <stdbool.h>
#include <user/app/init/shell.h>
#include <user/lib/elfload.h>
#include <user/lib/stdlib.h>
#include <user/app/init/tests/main.h>
static bool isspace(char c) {
return c == ' ' || c == '\t' || c == '\n';
}
static char *strsplit(char *base, char delim) {
if (!base) return NULL;
while (*base) {
if (delim ? *base == delim : isspace(*base)) {
*base++ = '\0';
return base;
}
base++;
}
return NULL;
}
static char *strtrim(char *s) {
char *end;
if (!s) return NULL;
while (isspace(*s)) s++;
end = s + strlen(s);
while (end > s && isspace(end[-1])) end--;
*end = '\0';
return s;
}
// TODO fgets
static int readline(char *buf, size_t max) {
char c = '\0';
size_t pos = 0;
while (pos < (max-1) && c != '\n' && file_read(stdin, &c, 1))
buf[pos++] = c;
buf[pos++] = '\0';
return pos;
}
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) {
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
if (buf[len-1] != '/') {
buf[len] = '/';
buf[len+1] = '\0';
}
}
file = file_open(buf, 0);
} else if (ls) { /* ls default argument */
file = file_open("/", 0);
} else { /* cat default argument */
file = file_clone(stdin);
}
if (!file) {
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), 0);
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");
}
close(fd);
}
static void cmd_touch(const char *args) {
int fd = _syscall_open(args, strlen(args), OPEN_CREATE);
if (fd < 0) {
printf("couldn't create file.\n");
return;
}
close(fd);
}
void shell_loop(void) {
static char buf[256];
int level = 0;
char *cmd, *args, *redir;
for (;;) {
printf("%x$ ", level);
readline(buf, 256);
redir = strtrim(strsplit(buf, '>'));
cmd = strtrim(buf);
args = strtrim(strsplit(cmd, 0));
/* "special" commands that can't be handled in a subprocess */
if (!strcmp(cmd, "shadow")) {
_syscall_mount(-1, args, strlen(args));
continue;
} else if (!strcmp(cmd, "exit")) {
_syscall_exit(0);
continue;
} else if (!strcmp(cmd, "fork")) {
if (!fork()) level++;
else _syscall_await();
continue;
}
if (!fork()) {
if (redir && !file_reopen(stdout, redir, OPEN_CREATE)) {
// TODO stderr
_syscall_exit(0);
}
if (!strcmp(cmd, "echo")) {
printf("%s\n", args);
} else if (!strcmp(cmd, "exec")) {
libc_file *file = file_open(args, 0);
if (!file) {
printf("couldn't open file\n");
} else {
elf_execf(file);
file_close(file);
printf("elf_execf failed\n");
}
} 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, "touch")) {
cmd_touch(args);
} else if (!strcmp(cmd, "run_tests")) {
test_all();
} else if (!strcmp(cmd, "stress")) {
stress_all();
} else {
printf("unknown command :(\n");
}
_syscall_exit(0);
} else {
_syscall_await();
}
}
}
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