chore: clang-format

pid_t is supported on musl, unlike __pid_t

Makefile

@@ -17,10 +17,10 @@ LDFLAGS?=-Wl,--gc-sections
 
 LIBS=-lpam
 
-_DEPS = version.h log.h util.h ui.h ui_state.h config.h pam.h desktop.h desktop_exec.h auth.h ofield.h efield.h keys.h users.h sessions.h chvt.h macros.h launch_state.h
+_DEPS = version.h log.h util.h ui.h ui_state.h config.h pam.h desktop.h desktop_exec.h auth.h ofield.h efield.h keys.h users.h sessions.h chvt.h macros.h launch_state.h signal_handler.h
 DEPS = $(patsubst %,$(IDIR)/%,$(_DEPS))
 
-_OBJ = main.o log.o util.o ui.o ui_state.o config.o pam.o desktop.o desktop_exec.o auth.o ofield.o efield.o users.o sessions.o chvt.o launch_state.o
+_OBJ = main.o log.o util.o ui.o ui_state.o config.o pam.o desktop.o desktop_exec.o auth.o ofield.o efield.o users.o sessions.o chvt.o launch_state.o signal_handler.o
 OBJ = $(patsubst %,$(ODIR)/%,$(_OBJ))
 
 INFO_GIT_REV?=$$(git describe --long --tags --always || echo '?')

include/desktop_exec.h

@@ -6,6 +6,7 @@
 
   #include "macros.h"
 
+char* NULLABLE search_path(const char* NNULLABLE for_binary);
 int execvpe_desktop(char** args, char* NNULLABLE* NNULLABLE envlist);
 int parse_exec_string(const char* exec_s, int* arg_count, char*** args);
 void free_parsed_args(int arg_count, char** args);

include/signal_handler.h

@@ -0,0 +1,3 @@
+// handle SIGTERM by sending SIGTERM to all children, resulting
+// in a graceful graphical shutdown
+void setup_sigterm();

src/auth.c

@@ -23,9 +23,7 @@
 #include "ui.h"
 #include "util.h"
 
-#define DEFAULT_XORG_DISPLAY 0
-// no PATH search for now
-#define XORG_COMMAND "/usr/bin/X"
+#define XORG_MESSAGE_LENGTH 16
 
 static void try_source_file(struct Vector* NNULLABLE vec_envlist,
                             char* NNULLABLE filepath) {
@@ -98,64 +96,121 @@ struct child_msg {
   bool err;
 };
 
-// TODO: OR check if xorg_pid fail exited
-static int wait_for_x_ready(const int xorg_pipefd[1], __pid_t xorg_pid) {
-  // TODO
-  UNUSED(xorg_pipefd);
-  UNUSED(xorg_pid);
-  sleep(2);
-  return 0;
+/// block until X returns the display number or an error occurs
+static bool x_get_display(const int xorg_pipefd[2], int* display) {
+  char buffer[XORG_MESSAGE_LENGTH];
+  bool status;
+
+  close(xorg_pipefd[1]);
+  ssize_t bytes_read = read(xorg_pipefd[0], buffer, sizeof(buffer) - 1);
+  buffer[bytes_read] = '\0';
+
+  if (bytes_read > 0) {
+    char* endptr;
+    int val = (int)strtol(buffer, &endptr, 10);
+    if (endptr == buffer) {
+      (void)fputs("failed to parse Xorg display response\n", stderr);
+      status = false;
+    } else {
+      *display = val;
+      status = true;
+    }
+  } else if (bytes_read == 0) {
+    (void)fputs("Xorg pipe closed\n", stderr);
+    status = false;
+  } else {
+    perror("read");
+    status = false;
+  }
+
+  close(xorg_pipefd[0]);
+  return status;
+}
+
+/// small helper to push dyn arr
+static void push_dyn_arr(void*** arr, void* item) {
+  struct Vector vec = vec_from_raw(*arr);
+  vec_push(&vec, item);
+  *arr = vec_as_raw(vec);
 }
 
 // TODO: properly pass this down
 extern int vt;
-// TODO: add error msgs
-static void launch_with_xorg_server(struct session_exec* NNULLABLE exec,
-                                    struct passwd* pw,
-                                    char** NNULLABLE envlist) {
-  int xorg_pipefd[2];
-  pipe(xorg_pipefd);
-  (void)fflush(NULL);
-  __pid_t xorg_pid = fork();
-  if (xorg_pid == 0) {
+
+static void start_xorg_server(struct passwd* pw, char** NNULLABLE envlist,
+                              int xorg_pipefd[2]) {
+  close(xorg_pipefd[0]);
   if (!pw->pw_dir) _exit(EXIT_FAILURE);
   // !!!!!!!!!! ATTENTION: this fails silently, of course add failure msgs but
   // for now I can't so be careful
   if (vt == -1) _exit(EXIT_FAILURE);
 
-    char* display_thing;
-    asprintf(&display_thing, ":%d", DEFAULT_XORG_DISPLAY);
-    if (!display_thing) _exit(EXIT_FAILURE);
+  // pass the pipe so Xorg can write the DISPLAY value in there
+  char* fd_str;
+  asprintf(&fd_str, "%d", xorg_pipefd[1]);
+  if (!fd_str) _exit(EXIT_FAILURE);
 
   char* vt_path;
   asprintf(&vt_path, "vt%d", vt);
   if (!vt_path) {
-      free(display_thing);
+    free(fd_str);
     _exit(EXIT_FAILURE);
   }
 
-    // dup2(xorg_pipefd[1], STDERR_FILENO);
-    // dup2(xorg_pipefd[1], STDOUT_FILENO);
-    // close(xorg_pipefd[0]);
-    // close(xorg_pipefd[1]);
+  char* xorg_path = search_path("Xorg");
+  if (!xorg_path) {
+    (void)fputs("couldn't find Xorg binary in PATH, sure it's installed?\n",
+                stderr);
+    _exit(EXIT_FAILURE);
+  }
 
-    int exit = execle(XORG_COMMAND, XORG_COMMAND, display_thing, vt_path, NULL,
+  int exit = execle(xorg_path, xorg_path, "-displayfd", fd_str, vt_path, NULL,
                     envlist);
   perror("exec");
-    // execle("X", "X", display_thing, vt_path, "-auth", xauth_path,
-    //        "-nolisten", "tcp", "-background", "none", NULL, envlist);
-
-    printf("wtf3\n");
-    (void)fflush(stdout);
 
   free(vt_path);
-    free(display_thing);
+  free(fd_str);
+  free(xorg_path);
   _exit(exit);
 }
 
-  wait_for_x_ready(xorg_pipefd, xorg_pid);
+// TODO: add error msgs
+/// returns on completion
+static void launch_with_xorg_server(struct session_exec* NNULLABLE exec,
+                                    struct passwd* pw,
+                                    char** NNULLABLE envlist) {
+  int xorg_pipefd[2];
+  if (pipe(xorg_pipefd) == -1) _exit(EXIT_FAILURE);
 
-  __pid_t xorg_session_pid = fork();
+  (void)fflush(NULL);
+  pid_t xorg_pid = fork();
+  if (xorg_pid == 0) {
+    start_xorg_server(pw, envlist, xorg_pipefd);
+  }
+
+  int display = 0;
+  if (!x_get_display(xorg_pipefd, &display)) {
+    (void)fputs("failed to get X display, aborting\n", stderr);
+    int status;
+    waitpid(xorg_pid, &status, 0);
+    _exit(EXIT_FAILURE);
+  }
+
+  char* display_env;
+  asprintf(&display_env, "DISPLAY=:%d", display);
+  if (!display_env) {
+    (void)fputs("failure allocating memory for DISPLAY string\n", stderr);
+    _exit(EXIT_FAILURE);
+  }
+  // convert back for convenient push-ing
+  push_dyn_arr((void***)&envlist, display_env);
+  if (!envlist) {
+    (void)fputs("failure allocating memory for DISPLAY env\n", stderr);
+    _exit(EXIT_FAILURE);
+  }
+
+  (void)fflush(NULL);
+  pid_t xorg_session_pid = fork();
   if (xorg_session_pid == 0) {
     int exit = session_exec_exec(exec, envlist);
     perror("exec error");
@@ -165,20 +220,16 @@ static void launch_with_xorg_server(struct session_exec* NNULLABLE exec,
 
   // looks weird, waiting on -1 should wait on any child and then just check if
   // its xorg server or the session and kill the other waiting on it
-  __pid_t pid;
+  pid_t pid;
   int status; // not even read for now
   while ((pid = waitpid(-1, &status, 0)) > 0) {
     if (pid == xorg_pid || pid == xorg_session_pid) {
-      __pid_t pid_to_kill = pid ^ xorg_pid ^ xorg_session_pid;
+      pid_t pid_to_kill = pid ^ xorg_pid ^ xorg_session_pid;
       if (pid == xorg_pid) printf("Xorg server died\n");
       if (pid == xorg_session_pid) printf("Xorg session died\n");
 
       kill(pid_to_kill, SIGTERM);
       waitpid(pid_to_kill, &status, 0);
-      printf("wtf %d, x%d s%d - k%d\n", status, xorg_pid, xorg_session_pid,
-             pid_to_kill);
-      (void)fflush(stdout);
-      sleep(10);
 
       break;
     }
@@ -218,6 +269,7 @@ inline static void forked(int pipefd[2], struct passwd* pw,
 
   if (session->type == XORG) {
     launch_with_xorg_server(&session->exec, pw, envlist);
+    _exit(EXIT_SUCCESS);
   } else {
     int exit = session_exec_exec(&session->exec, envlist);
     perror("exec error");
@@ -260,16 +312,6 @@ bool launch(char* user, char* passwd, struct session session, void (*cb)(void),
 
   struct Vector envlist_vec = vec_from_raw((void**)env_ret.envlist);
 
-  if (session.type == XORG) {
-    char* display_env;
-    asprintf(&display_env, "DISPLAY=:%d", DEFAULT_XORG_DISPLAY);
-    if (!display_env) {
-      print_err("alloc error");
-      return false;
-    }
-    vec_push(&envlist_vec, display_env);
-  }
-
   source_paths(&envlist_vec, &config->behavior.source, pw->pw_dir,
                &config->behavior.user_source);
   char** envlist = (char**)vec_as_raw(envlist_vec);

src/desktop_exec.c

@@ -17,7 +17,7 @@
 
 // returns NULL on any error
 // otherwise it returns the absolute path of the program that MUST BE FREED
-static char* NULLABLE search_path(const char* NNULLABLE for_binary) {
+char* NULLABLE search_path(const char* NNULLABLE for_binary) {
   if (strchr(for_binary, '/') != NULL) {
     // skip absolute paths
     return strdup(for_binary);

src/launch_state.c

@@ -21,19 +21,17 @@ int read_launch_state(struct LaunchState* NNULLABLE state) {
   };
 
   size_t num = 0;
-  if (getline(&state->username, &num, state_fd) < 0) goto fail;
-  // not sure I can actually prove it but ughh, getline < 0 will ensure there's
-  // something in the string and then I think strcspn is bounded to the final
-  // null byte, so it shouldn't go over
-  // NOLINTNEXTLINE(clang-analyzer-security.ArrayBound)
-  state->username[strcspn(state->username, "\n")] = 0;
+  ssize_t chars = getline(&state->username, &num, state_fd);
+  if (chars  < 0) goto fail;
+  if (state->username[chars] == '\n') state->username[chars] = 0;
 
   num = 0;
-  if (getline(&state->session_opt, &num, state_fd) < 0) {
+  chars = getline(&state->session_opt, &num, state_fd);
+  if (chars < 0) {
     free(state->session_opt);
     goto fail;
   }
-  state->session_opt[strcspn(state->session_opt, "\n")] = 0;
+  if (state->session_opt[chars] == '\n') state->session_opt[chars] = 0;
 
   (void)fclose(state_fd);
   return 0;

src/main.c

@@ -12,12 +12,14 @@
 #include "log.h"
 #include "macros.h"
 #include "sessions.h"
+#include "signal_handler.h"
 #include "ui.h"
 #include "users.h"
 #include "util.h"
 #include "version.h"
 
 #define DATESTR_MAXBUFSIZE 0x20
+
 int main(int argc, char* argv[]) {
   // Logger
   char* log_output = getenv("LIDM_LOG");
@@ -85,6 +87,8 @@ int main(int argc, char* argv[]) {
   struct Vector users = get_human_users();
   struct Vector sessions = get_avaliable_sessions();
 
+  setup_sigterm();
+
   int ret = load(&users, &sessions);
   if (ret == 0) execl(argv[0], argv[0], NULL);
 }

src/signal_handler.c

@@ -0,0 +1,27 @@
+#include <errno.h>
+#include <stddef.h>
+#include <sys/wait.h>
+#include <unistd.h>
+
+static void handle_sigterm(int sig) {
+  (void)sig;
+
+  (void)signal(SIGTERM, SIG_IGN);
+  kill(-getpgrp(), SIGTERM);
+
+  int status;
+  while (waitpid(-1, &status, 0) > 0 || errno == EINTR) {
+  }
+
+  _exit(0);
+}
+
+void setup_sigterm() {
+  setpgid(0, 0);
+
+  struct sigaction sa;
+  sa.sa_handler = handle_sigterm;
+  sigemptyset(&sa.sa_mask);
+  sa.sa_flags = 0;
+  sigaction(SIGTERM, &sa, NULL);
+}

src/ui.c

@@ -186,6 +186,7 @@ void ui_update_ofield(struct opts_field* NNULLABLE self) {
   ui_update_field(input);
 }
 
+/// draw everything
 void scratch_print_ui() {
   ioctl(STDOUT_FILENO, TIOCGWINSZ, &window);
   box_start = (struct uint_point){
@@ -201,7 +202,7 @@ void scratch_print_ui() {
     return;
   }
 
-  printf("\033[2J\033[H"); // Clear screen
+  printf("\033[2J\033[H\033c"); // Clear screen
 
   /// PRINTING
   // printf box
@@ -313,6 +314,8 @@ int load(struct Vector* users, struct Vector* sessions) {
                       &restore_all, g_config)) {
             print_passwd(utf8len(of_passwd.efield.content), true);
             ui_update_cursor_focus();
+          } else {
+            scratch_print_ui();
           }
         } else if (ansi_key == A_UP || ansi_key == A_DOWN) {
           st_ch_focus(ansi_key == A_DOWN ? 1 : -1);
@@ -336,6 +339,8 @@ int load(struct Vector* users, struct Vector* sessions) {
                     &restore_all, g_config)) {
           print_passwd(utf8len(of_passwd.efield.content), true);
           ui_update_cursor_focus();
+        } else {
+          scratch_print_ui();
         }
       } else
         st_kbd_type(seq, g_config->behavior.include_defshell);