1 files changed, 505 insertions, 0 deletions

diff --git a/src/pty.c b/src/pty.c
new file mode 100644
index 0000000..e5d47ed
--- /dev/null
+++ b/src/pty.c
@@ -0,0 +1,505 @@
+#include <errno.h>
+#include <fcntl.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#ifndef _WIN32
+#include <sys/ioctl.h>
+#include <sys/wait.h>
+
+#if defined(__OpenBSD__) || defined(__APPLE__)
+#include <util.h>
+#elif defined(__FreeBSD__)
+#include <libutil.h>
+#else
+#include <pty.h>
+#endif
+
+#if defined(__APPLE__)
+#include <crt_externs.h>
+#define environ (*_NSGetEnviron())
+#else
+extern char **environ;
+#endif
+#endif
+
+#include "pty.h"
+#include "utils.h"
+
+#ifdef _WIN32
+HRESULT (WINAPI *pCreatePseudoConsole)(COORD, HANDLE, HANDLE, DWORD, HPCON *);
+HRESULT (WINAPI *pResizePseudoConsole)(HPCON, COORD);
+void (WINAPI *pClosePseudoConsole)(HPCON);
+#endif
+
+static void alloc_cb(uv_handle_t *unused, size_t suggested_size, uv_buf_t *buf) {
+  buf->base = xmalloc(suggested_size);
+  buf->len = suggested_size;
+}
+
+static void close_cb(uv_handle_t *handle) { free(handle); }
+
+pty_buf_t *pty_buf_init(char *base, size_t len) {
+  pty_buf_t *buf = xmalloc(sizeof(pty_buf_t));
+  buf->base = xmalloc(len);
+  memcpy(buf->base, base, len);
+  buf->len = len;
+  return buf;
+}
+
+void pty_buf_free(pty_buf_t *buf) {
+  free(buf->base);
+  free(buf);
+}
+
+static void read_cb(uv_stream_t *stream, ssize_t n, const uv_buf_t *buf) {
+  uv_read_stop(stream);
+  pty_io_t *io = (pty_io_t *) stream->data;
+  if (n <= 0) {
+    if (n == UV_ENOBUFS || n == 0) return;
+    if (n != UV_EOF) printf("== uv_read failed with error %ld: %s\n", n, uv_strerror(n));
+    io->read_cb(io->ctx, NULL, true);
+    goto done;
+  }
+  io->read_cb(io->ctx, pty_buf_init(buf->base, (size_t) n), false);
+
+done:
+  free(buf->base);
+}
+
+static void write_cb(uv_write_t *req, int unused) {
+  pty_buf_t *buf = (pty_buf_t *) req->data;
+  pty_buf_free(buf);
+  free(req);
+}
+
+static pty_io_t *pty_io_init(pty_process *process, pty_read_cb read_cb) {
+  pty_io_t *io = xmalloc(sizeof(pty_io_t));
+  io->in = xmalloc(sizeof(uv_pipe_t));
+  io->out = xmalloc(sizeof(uv_pipe_t));
+  uv_pipe_init(process->loop, io->in, 0);
+  uv_pipe_init(process->loop, io->out, 0);
+  io->paused = true;
+  io->read_cb = read_cb;
+  io->ctx = process->ctx;
+  return io;
+}
+
+static void pty_io_free(pty_io_t *io) {
+  uv_close((uv_handle_t *) io->in, close_cb);
+  uv_close((uv_handle_t *) io->out, close_cb);
+  free(io);
+}
+
+pty_process *process_init(void *ctx, uv_loop_t *loop, char *argv[], char *envp[]) {
+  pty_process *process = xmalloc(sizeof(pty_process));
+  memset(process, 0, sizeof(pty_process));
+  process->ctx = ctx;
+  process->loop = loop;
+  process->argv = argv;
+  process->envp = envp;
+  process->columns = 80;
+  process->rows = 24;
+  process->exit_code = -1;
+  return process;
+}
+
+bool process_running(pty_process *process) {
+  return process != NULL && process->pid > 0 && uv_kill(process->pid, 0) == 0;
+}
+
+void process_free(pty_process *process) {
+  if (process == NULL) return;
+#ifdef _WIN32
+  if (process->si.lpAttributeList != NULL) {
+    DeleteProcThreadAttributeList(process->si.lpAttributeList);
+    free(process->si.lpAttributeList);
+  }
+  if (process->pty != NULL) pClosePseudoConsole(process->pty);
+  if (process->handle != NULL) CloseHandle(process->handle);
+#else
+  uv_thread_join(&process->tid);
+#endif
+  if (process->io != NULL) pty_io_free(process->io);
+  if (process->argv != NULL) free(process->argv);
+  if (process->cwd != NULL) free(process->cwd);
+  char **p = process->envp;
+  for (; *p; p++) free(*p);
+  free(process->envp);
+  free(process);
+}
+
+void pty_pause(pty_process *process) {
+  if (process == NULL) return;
+  pty_io_t *io = process->io;
+  if (io->paused) return;
+  uv_read_stop((uv_stream_t *) io->out);
+}
+
+void pty_resume(pty_process *process) {
+  if (process == NULL) return;
+  pty_io_t *io = process->io;
+  if (!io->paused) return;
+  io->out->data = io;
+  uv_read_start((uv_stream_t *) io->out, alloc_cb, read_cb);
+}
+
+int pty_write(pty_process *process, pty_buf_t *buf) {
+  if (process == NULL) {
+    pty_buf_free(buf);
+    return UV_ESRCH;
+  }
+  pty_io_t *io = process->io;
+  uv_buf_t b = uv_buf_init(buf->base, buf->len);
+  uv_write_t *req = xmalloc(sizeof(uv_write_t));
+  req->data = buf;
+  return uv_write(req, (uv_stream_t *) io->in, &b, 1, write_cb);
+}
+
+bool pty_resize(pty_process *process) {
+  if (process == NULL) return false;
+  if (process->columns <= 0 || process->rows <= 0) return false;
+#ifdef _WIN32
+  COORD size = {(int16_t) process->columns, (int16_t) process->rows};
+  return pResizePseudoConsole(process->pty, size) == S_OK;
+#else
+  struct winsize size = {process->rows, process->columns, 0, 0};
+  return ioctl(process->pty, TIOCSWINSZ, &size) == 0;
+#endif
+}
+
+bool pty_kill(pty_process *process, int sig) {
+  if (process == NULL) return false;
+  process->killed = true;
+#ifdef _WIN32
+  return TerminateProcess(process->handle, 1) != 0;
+#else
+  return uv_kill(-process->pid, sig) == 0;
+#endif
+}
+
+#ifdef _WIN32
+bool conpty_init() {
+  uv_lib_t kernel;
+  if (uv_dlopen("kernel32.dll", &kernel)) {
+    uv_dlclose(&kernel);
+    return false;
+  }
+  static struct {
+    char *name;
+    FARPROC *ptr;
+  } conpty_entry[] = {{"CreatePseudoConsole", (FARPROC *) &pCreatePseudoConsole},
+                      {"ResizePseudoConsole", (FARPROC *) &pResizePseudoConsole},
+                      {"ClosePseudoConsole", (FARPROC *) &pClosePseudoConsole},
+                      {NULL, NULL}};
+  for (int i = 0; conpty_entry[i].name != NULL && conpty_entry[i].ptr != NULL; i++) {
+    if (uv_dlsym(&kernel, conpty_entry[i].name, (void **) conpty_entry[i].ptr)) {
+      uv_dlclose(&kernel);
+      return false;
+    }
+  }
+  return true;
+}
+
+// convert argv to cmdline for CreateProcessW
+static WCHAR *join_args(char **argv) {
+  char *args = NULL;
+  char **ptr = argv;
+  for (; *ptr; ptr++) {
+    char *quoted = (char *) quote_arg(*ptr);
+    size_t arg_len = args == NULL ? 1 : strlen(args) + 1;
+    size_t quoted_len = strlen(quoted);
+    args = xrealloc(args, arg_len + quoted_len);
+    if (arg_len == 1) memset(args, 0, 2);
+    if (arg_len != 1) strcat(args, " ");
+    strncat(args, quoted, quoted_len);
+    if (quoted != *ptr) free(quoted);
+  }
+
+  int len = MultiByteToWideChar(CP_UTF8, 0, args, -1, NULL, 0);
+  if (len <= 0) goto failed;
+  WCHAR *ws = (WCHAR *) xmalloc(len * sizeof(WCHAR));
+  if (len != MultiByteToWideChar(CP_UTF8, 0, args, -1, ws, len)) {
+    free(ws);
+    goto failed;
+  }
+  return ws;
+
+failed:
+  if (args != NULL) free(args);
+  return NULL;
+}
+
+static WCHAR *to_utf16(char *str) {
+  int len = MultiByteToWideChar(CP_UTF8, 0, str, -1, NULL, 0);
+  if (len <= 0) return NULL;
+  WCHAR *wstr = xmalloc((len + 1) * sizeof(WCHAR));
+  if (len != MultiByteToWideChar(CP_UTF8, 0, str, -1, wstr, len)) {
+    free(wstr);
+    return NULL;
+  }
+  wstr[len] = L'\0';
+  return wstr;
+}
+
+static bool conpty_setup(HPCON *hnd, COORD size, STARTUPINFOEXW *si_ex, char **in_name, char **out_name) {
+  static int count = 0;
+  char buf[256];
+  HPCON pty = INVALID_HANDLE_VALUE;
+  SECURITY_ATTRIBUTES sa = {0};
+  HANDLE in_pipe = INVALID_HANDLE_VALUE;
+  HANDLE out_pipe = INVALID_HANDLE_VALUE;
+  const DWORD open_mode = PIPE_ACCESS_INBOUND | PIPE_ACCESS_OUTBOUND | FILE_FLAG_FIRST_PIPE_INSTANCE;
+  const DWORD pipe_mode = PIPE_TYPE_BYTE | PIPE_READMODE_BYTE | PIPE_WAIT;
+  DWORD pid = GetCurrentProcessId();
+  bool ret = false;
+
+  sa.nLength = sizeof(sa);
+  snprintf(buf, sizeof(buf), "\\\\.\\pipe\\ttyd-term-in-%d-%d", pid, count);
+  *in_name = strdup(buf);
+  snprintf(buf, sizeof(buf), "\\\\.\\pipe\\ttyd-term-out-%d-%d", pid, count);
+  *out_name = strdup(buf);
+  in_pipe = CreateNamedPipeA(*in_name, open_mode, pipe_mode, 1, 0, 0, 30000, &sa);
+  out_pipe = CreateNamedPipeA(*out_name, open_mode, pipe_mode, 1, 0, 0, 30000, &sa);
+  if (in_pipe == INVALID_HANDLE_VALUE || out_pipe == INVALID_HANDLE_VALUE) {
+    print_error("CreateNamedPipeA");
+    goto failed;
+  }
+
+  HRESULT hr = pCreatePseudoConsole(size, in_pipe, out_pipe, 0, &pty);
+  if (FAILED(hr)) {
+    print_error("CreatePseudoConsole");
+    goto failed;
+  }
+
+  si_ex->StartupInfo.cb = sizeof(STARTUPINFOEXW);
+  si_ex->StartupInfo.dwFlags |= STARTF_USESTDHANDLES;
+  si_ex->StartupInfo.hStdError = NULL;
+  si_ex->StartupInfo.hStdInput = NULL;
+  si_ex->StartupInfo.hStdOutput = NULL;
+  size_t bytes_required;
+  InitializeProcThreadAttributeList(NULL, 1, 0, &bytes_required);
+  si_ex->lpAttributeList = (PPROC_THREAD_ATTRIBUTE_LIST) xmalloc(bytes_required);
+  if (!InitializeProcThreadAttributeList(si_ex->lpAttributeList, 1, 0, &bytes_required)) {
+    print_error("InitializeProcThreadAttributeList");
+    goto failed;
+  }
+  if (!UpdateProcThreadAttribute(si_ex->lpAttributeList, 0, PROC_THREAD_ATTRIBUTE_PSEUDOCONSOLE, pty, sizeof(HPCON),
+                                 NULL, NULL)) {
+    print_error("UpdateProcThreadAttribute");
+    goto failed;
+  }
+  count++;
+  *hnd = pty;
+  ret = true;
+  goto done;
+
+failed:
+  ret = false;
+  free(*in_name);
+  *in_name = NULL;
+  free(*out_name);
+  *out_name = NULL;
+done:
+  if (in_pipe != INVALID_HANDLE_VALUE) CloseHandle(in_pipe);
+  if (out_pipe != INVALID_HANDLE_VALUE) CloseHandle(out_pipe);
+  return ret;
+}
+
+static void connect_cb(uv_connect_t *req, int status) { free(req); }
+
+static void CALLBACK conpty_exit(void *context, BOOLEAN unused) {
+  pty_process *process = (pty_process *) context;
+  uv_async_send(&process->async);
+}
+
+static void async_cb(uv_async_t *async) {
+  pty_process *process = (pty_process *) async->data;
+  UnregisterWait(process->wait);
+
+  DWORD exit_code;
+  GetExitCodeProcess(process->handle, &exit_code);
+  process->exit_code = (int) exit_code;
+  process->exit_signal = 1;
+  process->exit_cb(process->ctx, process);
+
+  uv_close((uv_handle_t *) async, NULL);
+  process_free(process);
+}
+
+int pty_spawn(pty_process *process, pty_read_cb read_cb, pty_exit_cb exit_cb) {
+  char *in_name = NULL;
+  char *out_name = NULL;
+  DWORD flags = EXTENDED_STARTUPINFO_PRESENT | CREATE_UNICODE_ENVIRONMENT;
+  COORD size = {(int16_t) process->columns, (int16_t) process->rows};
+
+  if (!conpty_setup(&process->pty, size, &process->si, &in_name, &out_name)) return 1;
+
+  SetConsoleCtrlHandler(NULL, FALSE);
+
+  int status = 1;
+  pty_io_t *io = pty_io_init(process, read_cb);
+
+  uv_connect_t *in_req = xmalloc(sizeof(uv_connect_t));
+  uv_connect_t *out_req = xmalloc(sizeof(uv_connect_t));
+  uv_pipe_connect(in_req, io->in, in_name, connect_cb);
+  uv_pipe_connect(out_req, io->out, out_name, connect_cb);
+
+  PROCESS_INFORMATION pi = {0};
+  WCHAR *cmdline, *cwd;
+  cmdline = join_args(process->argv);
+  if (cmdline == NULL) goto cleanup;
+  if (process->envp != NULL) {
+    char **p = process->envp;
+    for (; *p; p++) {
+      WCHAR *env = to_utf16(*p);
+      if (env == NULL) goto cleanup;
+      _wputenv(env);
+      free(env);
+    }
+  }
+  if (process->cwd != NULL) {
+    cwd = to_utf16(process->cwd);
+    if (cwd == NULL) goto cleanup;
+  }
+
+  if (!CreateProcessW(NULL, cmdline, NULL, NULL, FALSE, flags, NULL, cwd, &process->si.StartupInfo, &pi)) {
+    print_error("CreateProcessW");
+    goto cleanup;
+  }
+
+  process->pid = pi.dwProcessId;
+  process->handle = pi.hProcess;
+  process->io = io;
+  process->exit_cb = exit_cb;
+  process->async.data = process;
+  uv_async_init(process->loop, &process->async, async_cb);
+
+  if (!RegisterWaitForSingleObject(&process->wait, pi.hProcess, conpty_exit, process, INFINITE, WT_EXECUTEONLYONCE)) {
+    print_error("RegisterWaitForSingleObject");
+    pty_io_free(io);
+    goto cleanup;
+  }
+
+  status = 0;
+
+cleanup:
+  if (in_name != NULL) free(in_name);
+  if (out_name != NULL) free(out_name);
+  if (cmdline != NULL) free(cmdline);
+  if (cwd != NULL) free(cwd);
+  return status;
+}
+#else
+static bool fd_set_cloexec(const int fd) {
+  int flags = fcntl(fd, F_GETFD);
+  if (flags < 0) return false;
+  return (flags & FD_CLOEXEC) == 0 || fcntl(fd, F_SETFD, flags | FD_CLOEXEC) != -1;
+}
+
+static bool fd_duplicate(int fd, uv_pipe_t *pipe) {
+  int fd_dup = dup(fd);
+  if (fd_dup < 0) return false;
+
+  if (!fd_set_cloexec(fd_dup)) return false;
+
+  int status = uv_pipe_open(pipe, fd_dup);
+  if (status) close(fd_dup);
+  return status == 0;
+}
+
+static void wait_cb(void *arg) {
+  pty_process *process = (pty_process *) arg;
+
+  pid_t pid;
+  int stat;
+  do
+    pid = waitpid(process->pid, &stat, 0);
+  while (pid != process->pid && errno == EINTR);
+
+  if (WIFEXITED(stat)) {
+    process->exit_code = WEXITSTATUS(stat);
+  }
+  if (WIFSIGNALED(stat)) {
+    int sig = WTERMSIG(stat);
+    process->exit_code = 128 + sig;
+    process->exit_signal = sig;
+  }
+
+  uv_async_send(&process->async);
+}
+
+static void async_cb(uv_async_t *async) {
+  pty_process *process = (pty_process *) async->data;
+  process->exit_cb(process->ctx, process);
+
+  uv_close((uv_handle_t *) async, NULL);
+  process_free(process);
+}
+
+int pty_spawn(pty_process *process, pty_read_cb read_cb, pty_exit_cb exit_cb) {
+  int status = 0;
+
+  uv_disable_stdio_inheritance();
+
+  int master, pid;
+  struct winsize size = {process->rows, process->columns, 0, 0};
+  pid = forkpty(&master, NULL, NULL, &size);
+  if (pid < 0) {
+    status = -errno;
+    return status;
+  } else if (pid == 0) {
+    setsid();
+    if (process->cwd != NULL) chdir(process->cwd);
+    if (process->envp != NULL) {
+      char **p = process->envp;
+      for (; *p; p++) putenv(*p);
+    }
+    int ret = execvp(process->argv[0], process->argv);
+    if (ret < 0) {
+      perror("execvp failed\n");
+      _exit(-errno);
+    }
+  }
+
+  int flags = fcntl(master, F_GETFL);
+  if (flags == -1) {
+    status = -errno;
+    goto error;
+  }
+  if (fcntl(master, F_SETFD, flags | O_NONBLOCK) == -1) {
+    status = -errno;
+    goto error;
+  }
+  if (!fd_set_cloexec(master)) {
+    status = -errno;
+    goto error;
+  }
+
+  pty_io_t *io = pty_io_init(process, read_cb);
+  if (!fd_duplicate(master, io->in) || !fd_duplicate(master, io->out)) {
+    status = -errno;
+    pty_io_free(io);
+    goto error;
+  }
+
+  process->pty = master;
+  process->pid = pid;
+  process->io = io;
+  process->exit_cb = exit_cb;
+  process->async.data = process;
+  uv_async_init(process->loop, &process->async, async_cb);
+  uv_thread_create(&process->tid, wait_cb, process);
+
+  return 0;
+
+error:
+  close(master);
+  uv_kill(pid, SIGKILL);
+  waitpid(pid, NULL, 0);
+  return status;
+}
+#endif
\ No newline at end of file