From 950fc21ecf209891bd5fde61296277188c47f59a Mon Sep 17 00:00:00 2001 From: Přemysl Janouch Date: Tue, 7 Apr 2015 02:58:59 +0200 Subject: Make asynchronous status messages possible I. HATE. GNU. READLINE. --- json-rpc-shell.c | 52 ++++++++++++++++++++++++++++++++++++++++++++++------ 1 file changed, 46 insertions(+), 6 deletions(-) diff --git a/json-rpc-shell.c b/json-rpc-shell.c index ed287e9..1ff3120 100644 --- a/json-rpc-shell.c +++ b/json-rpc-shell.c @@ -190,6 +190,9 @@ static struct app_context iconv_t term_to_utf8; ///< Terminal encoding to UTF-8 iconv_t term_from_utf8; ///< UTF-8 to terminal encoding + + char *readline_prompt; ///< The prompt we use for readline + bool readline_prompt_shown; ///< Whether the prompt is shown now } g_ctx; @@ -302,9 +305,33 @@ log_message_attributed (void *user_data, const char *quote, const char *fmt, { FILE *stream = stderr; + // GNU readline is a huge piece of total crap; it seems that we must do + // these incredible shenanigans in order to intersperse readline output + // with asynchronous status messages + char *saved_line; + int saved_point; + + if (g_ctx.readline_prompt_shown) + { + saved_point = rl_point; + saved_line = rl_copy_text (0, rl_end); + rl_set_prompt (""); + rl_replace_line ("", 0); + rl_redisplay (); + } + print_attributed (&g_ctx, stream, user_data, "%s", quote); vprint_attributed (&g_ctx, stream, user_data, fmt, ap); fputs ("\n", stream); + + if (g_ctx.readline_prompt_shown) + { + rl_set_prompt (g_ctx.readline_prompt); + rl_replace_line (saved_line, 0); + rl_point = saved_point; + rl_redisplay (); + free (saved_line); + } } static void @@ -1691,10 +1718,19 @@ on_winch (EV_P_ ev_signal *handle, int revents) static void on_readline_input (char *line) { + // Otherwise the prompt is shown at all times + g_ctx.readline_prompt_shown = false; + if (!line) { + ev_break (EV_DEFAULT_ EVBREAK_ALL); + + // We must do this here, or the prompt gets printed twice. *shrug* rl_callback_handler_remove (); - ev_break (EV_DEFAULT_ EVBREAK_ONE); + + // Note that we don't set "readline_prompt_shown" back to true. + // This is so that we can safely do rl_callback_handler_remove when + // the program is terminated in an unusual manner (other than ^D). return; } @@ -1704,6 +1740,8 @@ on_readline_input (char *line) // Stupid readline forces us to use a global variable process_input (&g_ctx, line); free (line); + + g_ctx.readline_prompt_shown = true; } static void @@ -1876,15 +1914,14 @@ main (int argc, char *argv[]) xstrdup_printf ("%s/" PROGRAM_NAME "/history", data_home); (void) read_history (history_path); - char *prompt; if (!get_attribute_printer (stdout)) - prompt = xstrdup_printf ("json-rpc> "); + g_ctx.readline_prompt = xstrdup_printf ("json-rpc> "); else { // XXX: to be completely correct, we should use tputs, but we cannot const char *prompt_attrs = str_map_find (&g_ctx.config, ATTR_PROMPT); const char *reset_attrs = str_map_find (&g_ctx.config, ATTR_RESET); - prompt = xstrdup_printf ("%c%s%cjson-rpc> %c%s%c", + g_ctx.readline_prompt = xstrdup_printf ("%c%s%cjson-rpc> %c%s%c", RL_PROMPT_START_IGNORE, prompt_attrs, RL_PROMPT_END_IGNORE, RL_PROMPT_START_IGNORE, reset_attrs, RL_PROMPT_END_IGNORE); } @@ -1909,9 +1946,11 @@ main (int argc, char *argv[]) ev_io_start (EV_DEFAULT_ &tty_watcher); rl_catch_sigwinch = false; - rl_callback_handler_install (prompt, on_readline_input); - + g_ctx.readline_prompt_shown = true; + rl_callback_handler_install (g_ctx.readline_prompt, on_readline_input); ev_run (loop, 0); + if (g_ctx.readline_prompt_shown) + rl_callback_handler_remove (); putchar ('\n'); // User has terminated the program, let's save the history and clean up @@ -1928,6 +1967,7 @@ main (int argc, char *argv[]) iconv_close (g_ctx.term_to_utf8); g_ctx.backend->destroy (&g_ctx); free (origin); + free (g_ctx.readline_prompt); str_map_free (&g_ctx.config); free_terminal (); ev_loop_destroy (loop); -- cgit v1.2.3-70-g09d2