2 * Copyright (C) 2011 Andre Noll <maan@tuebingen.mpg.de>
4 * Licensed under the GPL v2. For licencing details see COPYING.
7 /** \file interactive.c Readline abstraction for interactive sessions. */
12 #include <readline/readline.h>
13 #include <readline/history.h>
14 #include <sys/ioctl.h>
18 #include "buffer_tree.h"
21 #include "interactive.h"
26 struct i9e_client_info *ici;
30 char empty_line[1000];
32 struct btr_node *stdout_btrn;
33 bool last_write_was_status;
34 bool line_handler_running;
41 static struct i9e_private i9e_private, *i9ep = &i9e_private;
44 * Return the error state of the i9e task.
46 * This is mainly useful for other tasks to tell whether the i9e task is still
49 * \return A negative return value of zero means the i9e task terminated. Only
50 * in this case it is safe to call ie9_close().
52 int i9e_get_error(void)
54 return task_status(i9ep->task);
57 static bool is_prefix(const char *partial, const char *full, size_t len)
60 len = strlen(partial);
61 return !strncmp(partial, full, len);
65 * Generator function for command completion. STATE lets us know whether
66 * to start from scratch; without any state (i.e. STATE == 0), then we
67 * start at the top of the list.
69 static char *command_generator(const char *text, int state)
71 static int list_index, len;
73 struct i9e_client_info *ici = i9ep->ici;
75 rl_attempted_completion_over = 1; /* disable filename completion */
77 * If this is a new word to complete, initialize now. This includes
78 * saving the length of TEXT for efficiency, and initializing the index
85 /* Return the next name which partially matches from the command list. */
86 while ((name = ici->completers[list_index].name)) {
88 if (is_prefix(text, name, len))
89 return para_strdup(name);
91 return NULL; /* no names matched */
94 static void reset_completion_result(struct i9e_completion_result *cr)
96 cr->dont_append_space = false;
97 cr->filename_completion_desired = false;
101 static void create_matches(struct i9e_completion_info *ci,
102 struct i9e_completer *completers,
103 struct i9e_completion_result *cr)
107 reset_completion_result(cr);
109 ret = create_argv(ci->buffer, " ", &ci->argv);
110 if (ret < 0 || !ci->argv[0])
114 ci->word_num = compute_word_num(ci->buffer, " ", ci->point);
115 for (i = 0; completers[i].name; i++) {
116 if (strcmp(completers[i].name, ci->argv[0]) != 0)
118 completers[i].completer(ci, cr);
121 PARA_DEBUG_LOG("current word: %d (%s)\n", ci->word_num,
122 ci->argv[ci->word_num]);
124 for (i = 0; cr->matches[i]; i++)
125 PARA_DEBUG_LOG("match %d: %s\n", i, cr->matches[i]);
128 static char *completion_generator(const char *word, int state)
130 static int list_index;
131 static char **argv, **matches;
132 struct i9e_completer *completers = i9ep->ici->completers;
133 struct i9e_completion_info ci = {
134 .word = (char *)word,
136 .buffer = rl_line_buffer,
138 struct i9e_completion_result cr = {.matches = NULL};
142 /* clean up previous matches and set defaults */
148 rl_completion_append_character = ' ';
149 rl_completion_suppress_append = false;
150 rl_attempted_completion_over = true;
152 create_matches(&ci, completers, &cr);
154 matches = cr.matches;
156 rl_completion_suppress_append = cr.dont_append_space;
157 rl_attempted_completion_over = !cr.filename_completion_desired;
161 return matches[list_index++];
165 * Attempt to complete on the contents of TEXT. START and END bound the
166 * region of rl_line_buffer that contains the word to complete. TEXT is
167 * the word to complete. We can use the entire contents of rl_line_buffer
168 * in case we want to do some simple parsing. Return the array of matches,
169 * or NULL if there aren't any.
171 static char **i9e_completer(const char *text, int start, __a_unused int end)
173 struct i9e_client_info *ici = i9ep->ici;
175 if (!ici->completers)
177 /* Complete on command names if this is the first word in the line. */
179 return rl_completion_matches(text, command_generator);
180 return rl_completion_matches(text, completion_generator);
184 * Prepare writing to stdout.
186 * \param producer The buffer tree node which produces output.
188 * The i9e subsystem maintains a buffer tree node which may be attached to
189 * another node which generates output (a "producer"). When attached, the i9e
190 * buffer tree node copies the buffers generated by the producer to stdout.
192 * This function attaches the i9e input queue to an output queue of \a
197 void i9e_attach_to_stdout(struct btr_node *producer)
199 btr_remove_node(&i9ep->stdout_btrn);
200 i9ep->stdout_btrn = btr_new_node(&(struct btr_node_description)
201 EMBRACE(.name = "interactive_stdout", .parent = producer));
202 rl_set_keymap(i9ep->bare_km);
205 static void wipe_bottom_line(void)
208 int n = i9ep->num_columns;
211 * For reasons beyond my understanding, writing more than 68 characters
212 * here causes MacOS to mess up the terminal. Writing a line of spaces
213 * in smaller chunks works fine though. Weird.
215 fprintf(i9ep->stderr_stream, "\r");
217 if (n >= sizeof(x)) {
218 fprintf(i9ep->stderr_stream, "%s", x);
223 fprintf(i9ep->stderr_stream, "%s", x);
226 fprintf(i9ep->stderr_stream, "\r");
229 #ifndef RL_FREE_KEYMAP_DECLARED
231 * Free all storage associated with a keymap.
233 * This function is not declared in the readline headers although the symbol is
234 * exported and the function is documented in the readline info file. So we
235 * have to declare it here.
237 * \param keymap The keymap to deallocate.
239 void rl_free_keymap(Keymap keymap);
243 * Reset the terminal and save the in-memory command line history.
245 * This should be called before the caller exits.
249 char *hf = i9ep->ici->history_file;
251 rl_free_keymap(i9ep->bare_km);
252 rl_callback_handler_remove();
258 static void clear_bottom_line(void)
263 if (rl_point == 0 && rl_end == 0)
264 return wipe_bottom_line();
266 * We might have a multi-line input that needs to be wiped here, so the
267 * simple printf("\r<space>\r") is insufficient. To workaround this, we
268 * remove the whole line, redisplay and restore the killed text.
271 text = rl_copy_text(0, rl_end);
272 rl_kill_full_line(0, 0);
274 wipe_bottom_line(); /* wipe out the prompt */
275 rl_insert_text(text);
280 static bool input_available(void)
283 struct timeval tv = {0, 0};
287 FD_SET(i9ep->ici->fds[0], &rfds);
288 ret = para_select(1, &rfds, NULL, &tv);
292 static void i9e_line_handler(char *line)
295 struct btr_node *dummy;
298 i9ep->input_eof = true;
304 dummy = btr_new_node(&(struct btr_node_description)
305 EMBRACE(.name = "dummy line handler"));
306 i9e_attach_to_stdout(dummy);
307 ret = i9ep->ici->line_handler(line);
309 PARA_WARNING_LOG("%s\n", para_strerror(-ret));
311 btr_remove_node(&dummy);
316 static int i9e_post_select(__a_unused struct sched *s, __a_unused void *context)
319 struct i9e_client_info *ici = i9ep->ici;
321 size_t sz, consumed = 0;
326 ret = -E_I9E_TERM_RQ;
327 if (i9ep->caught_sigterm)
330 if (i9ep->caught_sigint)
332 while (input_available())
333 rl_callback_read_char();
334 if (!i9ep->stdout_btrn)
336 ret = btr_node_status(i9ep->stdout_btrn, 0, BTR_NT_LEAF);
344 sz = btr_next_buffer(i9ep->stdout_btrn, &buf);
347 if (i9ep->last_write_was_status)
348 fprintf(i9ep->stderr_stream, "\n");
349 i9ep->last_write_was_status = false;
350 ret = xwrite(ici->fds[1], buf, sz);
353 btr_consume(i9ep->stdout_btrn, ret);
355 if (ret == sz && consumed < 10000)
359 if (i9ep->stdout_btrn) {
361 btr_remove_node(&i9ep->stdout_btrn);
362 rl_set_keymap(i9ep->standard_km);
363 rl_set_prompt(i9ep->ici->prompt);
369 i9ep->caught_sigint = false;
373 static void i9e_pre_select(struct sched *s, __a_unused void *context)
377 if (i9ep->input_eof || i9ep->caught_sigint || i9ep->caught_sigterm) {
381 if (i9ep->stdout_btrn) {
382 ret = btr_node_status(i9ep->stdout_btrn, 0, BTR_NT_LEAF);
388 para_fd_set(i9ep->ici->fds[1], &s->wfds, &s->max_fileno);
391 * fd[0] might have been reset to blocking mode if our job was moved to
392 * the background due to CTRL-Z or SIGSTOP, so set the fd back to
395 ret = mark_fd_nonblocking(i9ep->ici->fds[0]);
397 PARA_WARNING_LOG("set to nonblock failed: (fd0 %d, %s)\n",
398 i9ep->ici->fds[0], para_strerror(-ret));
399 para_fd_set(i9ep->ici->fds[0], &s->rfds, &s->max_fileno);
402 static void update_winsize(void)
405 int ret = ioctl(i9ep->ici->fds[2], TIOCGWINSZ, (char *)&w);
408 assert(w.ws_col < sizeof(i9ep->empty_line));
409 i9ep->num_columns = w.ws_col;
411 i9ep->num_columns = 80;
413 memset(i9ep->empty_line, ' ', i9ep->num_columns);
414 i9ep->empty_line[i9ep->num_columns] = '\0';
418 * Defined key sequences are mapped to keys starting with this offset. I.e.
419 * pressing the first defined key sequence yields the key number \p KEY_OFFSET.
421 static int dispatch_key(__a_unused int count, __a_unused int key)
425 for (i = i9ep->num_key_bindings - 1; i >= 0; i--) {
426 if (strcmp(rl_executing_keyseq, i9ep->ici->bound_keyseqs[i]))
428 ret = i9ep->ici->key_handler(i);
429 return ret < 0? ret : 0;
435 * Register the i9e task and initialize readline.
437 * \param ici The i9e configuration parameters set by the caller.
438 * \param s The scheduler instance to add the i9e task to.
440 * The caller must allocate and initialize the structure \a ici points to.
444 int i9e_open(struct i9e_client_info *ici, struct sched *s)
448 if (!isatty(ici->fds[0]))
449 return -E_I9E_SETUPTERM;
450 ret = mark_fd_nonblocking(ici->fds[0]);
453 ret = mark_fd_nonblocking(ici->fds[1]);
456 i9ep->task = task_register(&(struct task_info) {
458 .pre_select = i9e_pre_select,
459 .post_select = i9e_post_select,
463 rl_readline_name = "para_i9e";
464 rl_basic_word_break_characters = " ";
465 rl_attempted_completion_function = i9e_completer;
467 i9ep->stderr_stream = fdopen(ici->fds[2], "w");
468 setvbuf(i9ep->stderr_stream, NULL, _IONBF, 0);
470 i9ep->standard_km = rl_get_keymap();
471 i9ep->bare_km = rl_make_bare_keymap();
472 if (ici->bound_keyseqs) {
475 /* bind each key sequence to the our dispatcher */
476 for (i = 0; (seq = ici->bound_keyseqs[i]); i++)
477 rl_generic_bind(ISFUNC, seq, (char *)dispatch_key,
479 i9ep->num_key_bindings = i;
481 if (ici->history_file)
482 read_history(ici->history_file);
485 rl_callback_handler_install("", i9e_line_handler);
486 i9e_attach_to_stdout(ici->producer);
487 rl_set_keymap(i9ep->bare_km);
489 rl_callback_handler_install(i9ep->ici->prompt, i9e_line_handler);
493 static void reset_line_state(void)
495 if (i9ep->stdout_btrn)
498 rl_reset_line_state();
499 rl_forced_update_display();
503 * The log function of the i9e subsystem.
505 * \param ll Severity log level.
506 * \param fmt Printf-like format string.
508 * This clears the bottom line of the terminal if necessary and writes the
509 * string given by \a fmt to fd[2], where fd[] is the array provided earlier in
512 __printf_2_3 void i9e_log(int ll, const char* fmt,...)
516 if (ll < i9ep->ici->loglevel)
520 vfprintf(i9ep->stderr_stream, fmt, argp);
523 i9ep->last_write_was_status = false;
527 * Print the current status to stderr.
529 * \param buf The text to print.
530 * \param len The number of bytes in \a buf.
532 * This clears the bottom line, moves to the beginning of the line and prints
533 * the given text. If the length of this text exceeds the width of the
534 * terminal, the text is shortened by leaving out a part in the middle.
536 void ie9_print_status_bar(char *buf, unsigned len)
538 size_t x = i9ep->num_columns, y = (x - 4) / 2;
543 fprintf(i9ep->stderr_stream, "\r%s", buf);
544 fprintf(i9ep->stderr_stream, " .. ");
545 fprintf(i9ep->stderr_stream, "%s", buf + len - y);
551 strcpy(scratch + 1, buf);
552 memset(scratch + 1 + len, ' ', y);
553 scratch[1 + len + y] = '\r';
554 scratch[2 + len + y] = '\0';
555 fprintf(i9ep->stderr_stream, "\r%s", scratch);
557 i9ep->last_write_was_status = true;
561 * Tell i9e that the caller received a signal.
563 * \param sig_num The number of the signal received.
565 * Currently the function only cares about \p SIGINT, but this may change.
567 void i9e_signal_dispatch(int sig_num)
569 if (sig_num == SIGWINCH)
570 return update_winsize();
571 if (sig_num == SIGINT) {
572 fprintf(i9ep->stderr_stream, "\n");
573 rl_replace_line ("", false /* clear_undo */);
575 i9ep->caught_sigint = true;
577 if (sig_num == SIGTERM)
578 i9ep->caught_sigterm = true;
582 * Wrapper for select(2) which does not restart on interrupts.
584 * \param n \sa \ref para_select().
585 * \param readfds \sa \ref para_select().
586 * \param writefds \sa \ref para_select().
587 * \param timeout_tv \sa \ref para_select().
589 * \return \sa \ref para_select().
591 * The only difference between this function and \ref para_select() is that
592 * \ref i9e_select() returns zero if the select call returned \p EINTR.
594 int i9e_select(int n, fd_set *readfds, fd_set *writefds,
595 struct timeval *timeout_tv)
597 int ret = select(n, readfds, writefds, NULL, timeout_tv);
603 ret = -ERRNO_TO_PARA_ERROR(errno);
609 * Return the possible completions for a given word.
611 * \param word The word to complete.
612 * \param string_list All possible words in this context.
613 * \param result String list is returned here.
615 * This function never fails. If no completion was found, a string list of
616 * length zero is returned. In any case, the result must be freed by the caller
617 * using \ref free_argv().
619 * This function is independent of readline and may be called before
622 * \return The number of possible completions.
624 int i9e_extract_completions(const char *word, char **string_list,
627 char **matches = para_malloc(sizeof(char *));
628 int match_count = 0, matches_len = 1;
630 int len = strlen(word);
632 for (p = string_list; *p; p++) {
633 if (!is_prefix(word, *p, len))
636 if (match_count >= matches_len) {
638 matches = para_realloc(matches,
639 matches_len * sizeof(char *));
641 matches[match_count - 1] = para_strdup(*p);
643 matches[match_count] = NULL;
649 * Return the list of partially matching words.
651 * \param word The command to complete.
652 * \param completers The array containing all command names.
654 * This is similar to \ref i9e_extract_completions(), but completes on the
655 * command names in \a completers.
657 * \return See \ref i9e_extract_completions().
659 char **i9e_complete_commands(const char *word, struct i9e_completer *completers)
663 int i, match_count, len = strlen(word);
666 * In contrast to completing against an arbitrary string list, here we
667 * know all possible completions and expect that there will not be many
668 * of them. So it should be OK to iterate twice over all commands which
669 * simplifies the code a bit.
671 for (i = 0, match_count = 0; (cmd = completers[i].name); i++) {
672 if (is_prefix(word, cmd, len))
675 matches = para_malloc((match_count + 1) * sizeof(*matches));
676 for (i = 0, match_count = 0; (cmd = completers[i].name); i++)
677 if (is_prefix(word, cmd, len))
678 matches[match_count++] = para_strdup(cmd);
679 matches[match_count] = NULL;
684 * Complete according to the given options.
686 * \param opts All available options.
687 * \param ci Information which was passed to the completer.
688 * \param cr Result pointer.
690 * This convenience helper can be used to complete an option. The array of all
691 * possible options is passed as the first argument. Flags, i.e. options
692 * without an argument, are expected to be listed as strings of type "-X" in \a
693 * opts while options which require an argument should be passed with a
694 * trailing "=" character like "-X=".
696 * If the word can be uniquely completed to a flag option, an additional space
697 * character is appended to the output. For non-flag options no space character
700 void i9e_complete_option(char **opts, struct i9e_completion_info *ci,
701 struct i9e_completion_result *cr)
705 num_matches = i9e_extract_completions(ci->word, opts, &cr->matches);
706 if (num_matches == 1) {
707 char *opt = cr->matches[0];
708 char c = opt[strlen(opt) - 1];
710 cr->dont_append_space = true;
715 * Print possible completions to stdout.
717 * \param completers The array of completion functions.
719 * At the end of the output a line starting with "-o=", followed by the
720 * (possibly empty) list of completion options is printed. Currently, the only
721 * two completion options are "nospace" and "filenames". The former indicates
722 * that no space should be appended even for a unique match while the latter
723 * indicates that usual filename completion should be performed in addition to
724 * the previously printed options.
728 int i9e_print_completions(struct i9e_completer *completers)
730 struct i9e_completion_result cr;
731 struct i9e_completion_info ci;
736 reset_completion_result(&cr);
737 buf = getenv("COMP_POINT");
738 ci.point = buf? atoi(buf) : 0;
739 ci.buffer = para_strdup(getenv("COMP_LINE"));
741 ci.argc = create_argv(ci.buffer, " ", &ci.argv);
742 ci.word_num = compute_word_num(ci.buffer, " ", ci.point);
744 end = ci.buffer + ci.point;
745 for (p = end; p > ci.buffer && *p != ' '; p--)
751 ci.word = para_malloc(n + 1);
752 strncpy(ci.word, p, n);
755 PARA_DEBUG_LOG("line: %s, point: %d (%c), wordnum: %d, word: %s\n",
756 ci.buffer, ci.point, ci.buffer[ci.point], ci.word_num, ci.word);
757 if (ci.word_num == 0)
758 cr.matches = i9e_complete_commands(ci.word, completers);
760 create_matches(&ci, completers, &cr);
762 if (cr.matches && cr.matches[0]) {
763 for (i = 0; cr.matches[i]; i++)
764 printf("%s\n", cr.matches[i]);
768 if (cr.dont_append_space)
770 if (cr.filename_completion_desired)
771 printf(",filenames");
773 free_argv(cr.matches);