fix(editor): prevent UI redraw conflicts during editor suspend/resume

Guard against re-entrant editor launches, abort editor on Ctrl-Z,
and centralize suspend-aware redraws through prof_doupdate() to prevent
terminal corruption when SIGTSTP is received while editor is active.

Removes SIGUSR1 editor escape in favor of standard pkill <editor> recovery.

src/command/cmd_defs.c

@@ -2638,7 +2638,8 @@ static const struct cmd_t command_defs[] = {
       CMD_DESC(
               "Spawn external editor to edit message. "
               "After editing the inputline may appear empty. Press enter to send the text anyways. "
-              "Use /executable to set your favourite editor." )
+              "Use /executable to set your favourite editor. "
+              "Ctrl-Z in the editor aborts the session and returns to Profanity." )
     },
 
     { CMD_PREAMBLE("/correct-editor",

src/event/server_events.c

@@ -341,7 +341,7 @@ sv_ev_room_message(ProfMessage* message)
         status_bar_active(num, WIN_MUC, mucwin->roomjid);
 
         if ((g_strcmp0(mynick, message->from_jid->resourcepart) != 0) && (prefs_get_boolean(PREF_BEEP))) {
-            beep();
+            ui_beep();
         }
 
         // not currently on groupchat window
@@ -349,7 +349,7 @@ sv_ev_room_message(ProfMessage* message)
         status_bar_new(num, WIN_MUC, mucwin->roomjid);
 
         if ((g_strcmp0(mynick, message->from_jid->resourcepart) != 0) && (prefs_get_boolean(PREF_FLASH))) {
-            flash();
+            ui_flash();
         }
 
         cons_show_incoming_room_message(message->from_jid->resourcepart, mucwin->roomjid, num, mention, triggers, mucwin->unread, window);

src/profanity.c

@@ -70,6 +70,38 @@ static void _connect_default(const char* const account);
 pthread_mutex_t lock;
 static gboolean force_quit = FALSE;
 
+static volatile sig_atomic_t suspend_requested = FALSE;
+static volatile sig_atomic_t cont_requested = FALSE;
+
+static void
+_handle_suspend_signals(void)
+{
+    if (cont_requested) {
+        cont_requested = FALSE;
+        if (!editor_is_active()) {
+            clearok(stdscr, TRUE);
+            ui_resize();
+        }
+    }
+
+    if (editor_check_stopped()) {
+        log_info("[Editor] stopped; aborting back to profanity");
+        suspend_requested = FALSE;
+        editor_emergency_kill();
+    } else if (suspend_requested) {
+        suspend_requested = FALSE;
+        if (editor_is_active()) {
+            log_info("[Editor] SIGTSTP from vim group; deferring to next poll");
+        } else {
+            log_info("[Suspend] dropping to shell");
+            if (!isendwin()) {
+                endwin();
+            }
+            kill(0, SIGSTOP);
+        }
+    }
+}
+
 void
 prof_run(gchar* log_level, gchar* account_name, gchar* config_file, gchar* log_file, gchar* theme_name, gchar** commands)
 {
@@ -93,6 +125,7 @@ prof_run(gchar* log_level, gchar* account_name, gchar* config_file, gchar* log_f
     int waittime = 0;
     while (cont && !force_quit) {
         log_stderr_handler();
+        _handle_suspend_signals();
         session_check_autoaway();
 
         line = commands ? *commands : inp_readline();
@@ -182,6 +215,18 @@ sigterm_handler(int sig)
     force_quit = TRUE;
 }
 
+static void
+sigtstp_handler(int sig)
+{
+    suspend_requested = TRUE;
+}
+
+static void
+sigcont_handler(int sig)
+{
+    cont_requested = TRUE;
+}
+
 static void
 _init(char* log_level, char* config_file, char* log_file, char* theme_name)
 {
@@ -189,7 +234,8 @@ _init(char* log_level, char* config_file, char* log_file, char* theme_name)
     // ignore SIGPIPE
     signal(SIGPIPE, SIG_IGN);
     signal(SIGINT, SIG_IGN);
-    signal(SIGTSTP, SIG_IGN);
+    signal(SIGTSTP, sigtstp_handler);
+    signal(SIGCONT, sigcont_handler);
     signal(SIGWINCH, ui_sigwinch_handler);
     signal(SIGTERM, sigterm_handler);
     signal(SIGHUP, sigterm_handler);

src/tools/editor.c

@@ -32,9 +32,15 @@ typedef struct EditorContext
     void* user_data;
 } EditorContext;
 
+static gboolean editor_active = FALSE; // re-entrancy guard
+static pid_t editor_pid = 0;
+
 static void
 _editor_exit_cb(GPid pid, gint status, gpointer data)
 {
+    editor_active = FALSE;
+    editor_pid = 0;
+
     EditorContext* ctx = data;
     gchar* contents = NULL;
     GError* error = NULL;
@@ -52,8 +58,10 @@ _editor_exit_cb(GPid pid, gint status, gpointer data)
             cons_show_error("Could not read edited content: %s", error->message);
             g_error_free(error);
         }
-    } else {
-        cons_show_error("Editor exited with error status %d", WEXITSTATUS(status));
+    } else if (WIFEXITED(status)) {
+        cons_show_error("Editor exited with status %d", WEXITSTATUS(status));
+    } else if (WIFSIGNALED(status)) {
+        cons_show("Editor session cancelled.");
     }
 
     if (remove(ctx->filename) != 0) {
@@ -70,6 +78,11 @@ _editor_exit_cb(GPid pid, gint status, gpointer data)
 gboolean
 launch_editor(gchar* initial_content, void (*callback)(gchar* content, void* data), void* user_data)
 {
+    if (editor_active) {
+        cons_show_error("An editor session is already active.");
+        return TRUE;
+    }
+
     auto_gchar gchar* filename = NULL;
     auto_gerror GError* glib_error = NULL;
     const char* jid = connection_get_barejid();
@@ -118,6 +131,7 @@ launch_editor(gchar* initial_content, void (*callback)(gchar* content, void* dat
     ctx->callback = callback;
     ctx->user_data = user_data;
 
+    editor_active = TRUE;
     ui_suspend();
 
     // Force GLib to install its SIGCHLD handler before forking. Creating a
@@ -129,6 +143,7 @@ launch_editor(gchar* initial_content, void (*callback)(gchar* content, void* dat
     pid_t pid = fork();
     if (pid == -1) {
         log_error("[Editor] Failed to fork: %s", strerror(errno));
+        editor_active = FALSE;
         ui_resume();
         ui_resize();
         cons_show_error("Failed to start editor: %s", strerror(errno));
@@ -139,7 +154,8 @@ launch_editor(gchar* initial_content, void (*callback)(gchar* content, void* dat
     } else if (pid == 0) {
         // Child process: Inherits TTY from parent
 
-        // Reset signal handlers that profanity sets so the editor doesn't inherit them
+        // SIGTSTP=SIG_DFL lets vim's :stop / Ctrl-Z work; profanity catches
+        // the STOPPED state via editor_check_stopped() and drops to the shell.
         signal(SIGINT, SIG_DFL);
         signal(SIGTSTP, SIG_DFL);
         signal(SIGPIPE, SIG_DFL);
@@ -151,7 +167,39 @@ launch_editor(gchar* initial_content, void (*callback)(gchar* content, void* dat
     }
 
     // Parent process: Watch the child asynchronously
+    editor_pid = pid;
     g_child_watch_add((GPid)pid, _editor_exit_cb, ctx);
     g_strfreev(editor_argv);
     return FALSE;
 }
+
+void
+editor_emergency_kill(void)
+{
+    if (!editor_active || editor_pid <= 0) {
+        return;
+    }
+    log_warning("[Editor] aborting editor pid %d", editor_pid);
+    kill(editor_pid, SIGCONT); // wake if STOPPED; no-op otherwise
+    kill(editor_pid, SIGTERM);
+    // _editor_exit_cb will restore the UI when the child reaps.
+}
+
+gboolean
+editor_is_active(void)
+{
+    return editor_active;
+}
+
+gboolean
+editor_check_stopped(void)
+{
+    // Poll for STOPPED without reaping (g_child_watch handles exit via its
+    // own WNOHANG). Lets prof_run drop the group to the shell on Ctrl-Z.
+    if (!editor_active || editor_pid <= 0) {
+        return FALSE;
+    }
+    int status;
+    pid_t r = waitpid(editor_pid, &status, WNOHANG | WUNTRACED);
+    return (r == editor_pid && WIFSTOPPED(status));
+}

src/tools/editor.h

@@ -16,4 +16,13 @@
 
 gboolean launch_editor(gchar* initial_content, void (*callback)(gchar* content, void* data), void* user_data);
 
+void editor_emergency_kill(void); // SIGCONT+SIGTERM the editor child
+
+// TRUE if editor child is STOPPED (Ctrl-Z / :stop / gdb-attach). Does not
+// reap; g_child_watch keeps handling exit.
+gboolean editor_check_stopped(void);
+
+// Editor-session flag accessor. Used by prof_run on SIGCONT resume.
+gboolean editor_is_active(void);
+
 #endif

src/ui/chatwin.c

@@ -327,7 +327,7 @@ chatwin_incoming_msg(ProfChatWin* chatwin, ProfMessage* message, gboolean win_cr
             cons_show_incoming_message(display_name, num, chatwin->unread, window);
 
             if (prefs_get_boolean(PREF_FLASH)) {
-                flash();
+                ui_flash();
             }
 
             chatwin->unread++;
@@ -364,7 +364,7 @@ chatwin_incoming_msg(ProfChatWin* chatwin, ProfMessage* message, gboolean win_cr
         wins_add_quotes_ac(window, message->plain, FALSE);
 
         if (prefs_get_boolean(PREF_BEEP)) {
-            beep();
+            ui_beep();
         }
     }
 

src/ui/core.c

@@ -54,6 +54,7 @@
 
 static int inp_size;
 static gboolean perform_resize = FALSE;
+static gboolean ui_suspended = FALSE;
 static GTimer* ui_idle_time;
 static WINDOW* main_scr;
 
@@ -63,6 +64,14 @@ static Display* display;
 
 static void _ui_draw_term_title(void);
 
+// Fail-safe gate: authoritative flag (doesn't depend on isendwin staying
+// TRUE), plus the regular endwin check for shutdown.
+static gboolean
+_ui_redraw_suspended(void)
+{
+    return ui_suspended || isendwin();
+}
+
 static void
 _ui_close(void)
 {
@@ -120,8 +129,7 @@ ui_sigwinch_handler(int sig)
 void
 ui_update(void)
 {
-    // UI is suspended
-    if (isendwin()) {
+    if (_ui_redraw_suspended()) {
         return;
     }
 
@@ -138,7 +146,7 @@ ui_update(void)
     title_bar_update_virtual();
     status_bar_draw();
     inp_put_back();
-    doupdate();
+    prof_doupdate();
 
     if (perform_resize) {
         perform_resize = FALSE;
@@ -180,21 +188,49 @@ void
 ui_suspend(void)
 {
     inp_suspend();
+    // Flush before flipping the flag (prof_doupdate skips while suspended).
+    prof_doupdate();
+    ui_suspended = TRUE;
     endwin();
 }
 
 void
 ui_resume(void)
 {
+    ui_suspended = FALSE;
+    clearok(stdscr, TRUE); // ncurses can't see vim's screen clobber
     refresh();
     inp_resume();
 }
 
+void
+ui_beep(void)
+{
+    if (!isendwin()) {
+        beep();
+    }
+}
+
+void
+ui_flash(void)
+{
+    if (!isendwin()) {
+        flash();
+    }
+}
+
+void
+prof_doupdate(void)
+{
+    if (!_ui_redraw_suspended()) {
+        doupdate();
+    }
+}
+
 void
 ui_resize(void)
 {
-    // UI is suspended
-    if (isendwin()) {
+    if (_ui_redraw_suspended()) {
         return;
     }
 
@@ -216,8 +252,7 @@ ui_resize(void)
 void
 ui_redraw(void)
 {
-    // UI is suspended
-    if (isendwin()) {
+    if (_ui_redraw_suspended()) {
         return;
     }
 

src/ui/inputwin.c

@@ -182,7 +182,11 @@ inp_readline(void)
 {
     // UI is suspended
     if (is_suspended || isendwin()) {
+        // Mirror the normal-path unlock so workers aren't starved
+        // for the whole editor session.
+        pthread_mutex_unlock(&lock);
         g_usleep(100000); // 100ms
+        pthread_mutex_lock(&lock);
         return NULL;
     }
 
@@ -311,11 +315,13 @@ inp_get_line(void)
     werase(inp_win);
     wmove(inp_win, 0, 0);
     _inp_win_update_virtual();
-    doupdate();
+    prof_doupdate();
     char* line = NULL;
     while (!line) {
         line = inp_readline();
         ui_update();
+        while (g_main_context_iteration(NULL, FALSE)) // non-blocking; bounded by ready sources
+            ;
     }
     status_bar_clear_prompt();
     return line;
@@ -338,12 +344,14 @@ inp_get_password(void)
     werase(inp_win);
     wmove(inp_win, 0, 0);
     _inp_win_update_virtual();
-    doupdate();
+    prof_doupdate();
     char* password = NULL;
     get_password = TRUE;
     while (!password) {
         password = inp_readline();
         ui_update();
+        while (g_main_context_iteration(NULL, FALSE)) // non-blocking; bounded by ready sources
+            ;
     }
     get_password = FALSE;
     status_bar_clear_prompt();
@@ -459,7 +467,7 @@ _inp_write(char* line, int offset)
     _inp_win_handle_scroll();
 
     _inp_win_update_virtual();
-    doupdate();
+    prof_doupdate();
 }
 
 static int

src/ui/privwin.c

@@ -57,7 +57,7 @@ privwin_incoming_msg(ProfPrivateWin* privatewin, ProfMessage* message)
         privatewin->unread++;
 
         if (prefs_get_boolean(PREF_FLASH)) {
-            flash();
+            ui_flash();
         }
     }
 
@@ -65,7 +65,7 @@ privwin_incoming_msg(ProfPrivateWin* privatewin, ProfMessage* message)
     wins_add_quotes_ac(window, message->plain, TRUE);
 
     if (prefs_get_boolean(PREF_BEEP)) {
-        beep();
+        ui_beep();
     }
 
     if (notify) {

src/ui/ui.h

@@ -43,6 +43,9 @@ void ui_load_colours(void);
 void ui_update(void);
 void ui_redraw(void);
 void ui_resize(void);
+// doupdate() wrapper that skips when the UI is suspended. Use this instead
+// of raw doupdate() to avoid the per-site whitelist class of bug.
+void prof_doupdate(void);
 void ui_focus_win(ProfWin* window);
 void ui_sigwinch_handler(int sig);
 void ui_handle_otr_error(const char* const barejid, const char* const message);
@@ -84,6 +87,8 @@ void ui_handle_recipient_error(const char* const recipient, const char* const er
 void ui_handle_error(const char* const err_msg);
 void ui_clear_win_title(void);
 void ui_goodbye_title(void);
+void ui_beep(void);
+void ui_flash(void);
 void ui_handle_room_configuration_form_error(const char* const roomjid, const char* const message);
 void ui_handle_room_config_submit_result(const char* const roomjid);
 void ui_handle_room_config_submit_result_error(const char* const roomjid, const char* const message);

tests/unittests/ui/stub_ui.c

@@ -85,6 +85,10 @@ void
 ui_resize(void)
 {
 }
+void
+prof_doupdate(void)
+{
+}
 
 void
 ui_focus_win(ProfWin* win)
@@ -1475,3 +1479,13 @@ ui_is_suspended(void)
 {
     return FALSE;
 }
+
+void
+ui_beep(void)
+{
+}
+
+void
+ui_flash(void)
+{
+}