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#include <LibC/stdio.h>
#include <LibC/unistd.h>
#include <LibC/process.h>
#include <LibC/errno.h>
#include <LibC/string.h>
#include <LibC/stdlib.h>
char* g_cwd = nullptr;
static void prompt()
{
if (getuid() == 0)
printf("# ");
else
printf("$ ");
}
static int sh_pwd(int, const char**)
{
printf("cwd: %s\n", g_cwd);
}
static int sh_cd(int argc, const char** argv)
{
if (argc == 1) {
printf("usage: cd <path>\n");
return 0;
}
char pathbuf[128];
if (argv[1][1] == '/')
memcpy(pathbuf, argv[1], strlen(argv[1]));
else
sprintf(pathbuf, "%s/%s", g_cwd, argv[1]);
struct stat st;
int rc = lstat(pathbuf, &st);
if (rc < 0) {
printf("lstat(%s) failed: %s\n", pathbuf, strerror(errno));
return 1;
}
if (!S_ISDIR(st.st_mode)) {
printf("Not a directory: %s\n", pathbuf);
return 1;
}
rc = chdir(pathbuf);
if (rc < 0) {
printf("chdir(%s) failed: %s\n", pathbuf, strerror(errno));
return 1;
}
memcpy(g_cwd, pathbuf, strlen(pathbuf));
return 0;
}
static bool handle_builtin(int argc, const char** argv, int& retval)
{
if (argc == 0)
return false;
if (!strcmp(argv[0], "cd")) {
retval = sh_cd(argc, argv);
return true;
}
if (!strcmp(argv[0], "pwd")) {
retval = sh_pwd(argc, argv);
return true;
}
return false;
}
static int runcmd(char* cmd)
{
if (cmd[0] == 0)
return 0;
char buf[128];
memcpy(buf, cmd, 128);
const char* argv[32];
size_t argi = 1;
argv[0] = &buf[0];
size_t buflen = strlen(buf);
for (size_t i = 0; i < buflen; ++i) {
if (buf[i] == ' ') {
buf[i] = '\0';
argv[argi++] = &buf[i + 1];
}
}
argv[argi + 1] = nullptr;
int retval = 0;
if (handle_builtin(argi, argv, retval)) {
return 0;
}
const char* search_path = "/bin";
char pathbuf[128];
sprintf(pathbuf, "%s/%s", search_path, argv[0]);
int ret = spawn(pathbuf, argv);
if (ret == -1) {
printf("spawn failed: %s (%s)\n", cmd, strerror(errno));
return 1;
}
// FIXME: waitpid should give us the spawned process's exit status
waitpid(ret);
return retval;
}
int main(int, char**)
{
char linebuf[128];
int linedx = 0;
linebuf[0] = '\0';
int fd = open("/dev/keyboard");
if (fd == -1) {
printf("failed to open /dev/keyboard :(\n");
return 1;
}
g_cwd = (char*)malloc(1024);
g_cwd[0] = '/';
g_cwd[1] = '\0';
prompt();
for (;;) {
char keybuf[16];
ssize_t nread = read(fd, keybuf, sizeof(keybuf));
if (nread < 0) {
printf("failed to read :(\n");
return 2;
}
if (nread > 2)
printf("read %u bytes\n", nread);
if (nread > (ssize_t)sizeof(keybuf)) {
printf("read() overran the buffer i gave it!\n");
return 3;
}
for (ssize_t i = 0; i < nread; ++i) {
putchar(keybuf[i]);
if (keybuf[i] != '\n') {
linebuf[linedx++] = keybuf[i];
linebuf[linedx] = '\0';
} else {
runcmd(linebuf);
linebuf[0] = '\0';
linedx = 0;
prompt();
}
}
}
return 0;
}
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