2 * Copyright (C) 2011-2014 Andre Noll <maan@systemlinux.org>
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>
20 #include "buffer_tree.h"
23 #include "interactive.h"
28 struct i9e_client_info
*ici
;
31 char empty_line
[1000];
33 struct btr_node
*stdout_btrn
;
34 bool last_write_was_status
;
35 bool line_handler_running
;
42 static struct i9e_private i9e_private
, *i9ep
= &i9e_private
;
45 * Return the error state of the i9e task.
47 * This is mainly useful for other tasks to tell whether the i9e task is still
50 * \return A negative return value of zero means the i9e task terminated. Only
51 * in this case it is safe to call ie9_close().
53 int i9e_get_error(void)
55 return i9ep
->task
->error
;
58 static bool is_prefix(const char *partial
, const char *full
, size_t len
)
61 len
= strlen(partial
);
62 return !strncmp(partial
, full
, len
);
66 * Generator function for command completion. STATE lets us know whether
67 * to start from scratch; without any state (i.e. STATE == 0), then we
68 * start at the top of the list.
70 static char *command_generator(const char *text
, int state
)
72 static int list_index
, len
;
74 struct i9e_client_info
*ici
= i9ep
->ici
;
76 rl_attempted_completion_over
= 1; /* disable filename completion */
78 * If this is a new word to complete, initialize now. This includes
79 * saving the length of TEXT for efficiency, and initializing the index
86 /* Return the next name which partially matches from the command list. */
87 while ((name
= ici
->completers
[list_index
].name
)) {
89 if (is_prefix(text
, name
, len
))
90 return para_strdup(name
);
92 return NULL
; /* no names matched */
95 static void reset_completion_result(struct i9e_completion_result
*cr
)
97 cr
->dont_append_space
= false;
98 cr
->filename_completion_desired
= false;
102 static void create_matches(struct i9e_completion_info
*ci
,
103 struct i9e_completer
*completers
,
104 struct i9e_completion_result
*cr
)
108 reset_completion_result(cr
);
110 ret
= create_argv(ci
->buffer
, " ", &ci
->argv
);
111 if (ret
< 0 || !ci
->argv
[0])
115 ci
->word_num
= compute_word_num(ci
->buffer
, " ", ci
->point
);
116 for (i
= 0; completers
[i
].name
; i
++) {
117 if (strcmp(completers
[i
].name
, ci
->argv
[0]) != 0)
119 completers
[i
].completer(ci
, cr
);
122 PARA_DEBUG_LOG("current word: %d (%s)\n", ci
->word_num
,
123 ci
->argv
[ci
->word_num
]);
125 for (i
= 0; cr
->matches
[i
]; i
++)
126 PARA_DEBUG_LOG("match %d: %s\n", i
, cr
->matches
[i
]);
129 static char *completion_generator(const char *word
, int state
)
131 static int list_index
;
132 static char **argv
, **matches
;
133 struct i9e_completer
*completers
= i9ep
->ici
->completers
;
134 struct i9e_completion_info ci
= {
135 .word
= (char *)word
,
137 .buffer
= rl_line_buffer
,
139 struct i9e_completion_result cr
= {.matches
= NULL
};
143 /* clean up previous matches and set defaults */
149 rl_completion_append_character
= ' ';
150 rl_completion_suppress_append
= false;
151 rl_attempted_completion_over
= true;
153 create_matches(&ci
, completers
, &cr
);
155 matches
= cr
.matches
;
157 rl_completion_suppress_append
= cr
.dont_append_space
;
158 rl_attempted_completion_over
= !cr
.filename_completion_desired
;
162 return matches
[list_index
++];
166 * Attempt to complete on the contents of TEXT. START and END bound the
167 * region of rl_line_buffer that contains the word to complete. TEXT is
168 * the word to complete. We can use the entire contents of rl_line_buffer
169 * in case we want to do some simple parsing. Return the array of matches,
170 * or NULL if there aren't any.
172 static char **i9e_completer(const char *text
, int start
, __a_unused
int end
)
174 struct i9e_client_info
*ici
= i9ep
->ici
;
176 if (!ici
->completers
)
178 /* Complete on command names if this is the first word in the line. */
180 return rl_completion_matches(text
, command_generator
);
181 return rl_completion_matches(text
, completion_generator
);
185 * Prepare writing to stdout.
187 * \param producer The buffer tree node which produces output.
189 * The i9e subsystem maintains a buffer tree node which may be attached to
190 * another node which generates output (a "producer"). When attached, the i9e
191 * buffer tree node copies the buffers generated by the producer to stdout.
193 * This function attaches the i9e input queue to an output queue of \a
198 void i9e_attach_to_stdout(struct btr_node
*producer
)
200 btr_remove_node(&i9ep
->stdout_btrn
);
201 i9ep
->stdout_btrn
= btr_new_node(&(struct btr_node_description
)
202 EMBRACE(.name
= "interactive_stdout", .parent
= producer
));
203 rl_set_keymap(i9ep
->bare_km
);
206 static void wipe_bottom_line(void)
209 int n
= i9ep
->num_columns
;
212 * For reasons beyond my understanding, writing more than 68 characters
213 * here causes MacOS to mess up the terminal. Writing a line of spaces
214 * in smaller chunks works fine though. Weird.
216 fprintf(i9ep
->stderr_stream
, "\r");
218 if (n
>= sizeof(x
)) {
219 fprintf(i9ep
->stderr_stream
, "%s", x
);
224 fprintf(i9ep
->stderr_stream
, "%s", x
);
227 fprintf(i9ep
->stderr_stream
, "\r");
230 #ifndef RL_FREE_KEYMAP_DECLARED
232 * Free all storage associated with a keymap.
234 * This function is not declared in the readline headers although the symbol is
235 * exported and the function is documented in the readline info file. So we
236 * have to declare it here.
238 * \param keymap The keymap to deallocate.
240 void rl_free_keymap(Keymap keymap
);
244 * Reset the terminal and save the in-memory command line history.
246 * This should be called before the caller exits.
250 char *hf
= i9ep
->ici
->history_file
;
252 rl_free_keymap(i9ep
->bare_km
);
253 rl_callback_handler_remove();
259 static void clear_bottom_line(void)
264 if (rl_point
== 0 && rl_end
== 0)
265 return wipe_bottom_line();
267 * We might have a multi-line input that needs to be wiped here, so the
268 * simple printf("\r<space>\r") is insufficient. To workaround this, we
269 * remove the whole line, redisplay and restore the killed text.
272 text
= rl_copy_text(0, rl_end
);
273 rl_kill_full_line(0, 0);
275 wipe_bottom_line(); /* wipe out the prompt */
276 rl_insert_text(text
);
281 static bool input_available(void)
284 struct timeval tv
= {0, 0};
288 FD_SET(i9ep
->ici
->fds
[0], &rfds
);
289 ret
= para_select(1, &rfds
, NULL
, &tv
);
293 static void i9e_line_handler(char *line
)
296 struct btr_node
*dummy
;
299 i9ep
->input_eof
= true;
305 dummy
= btr_new_node(&(struct btr_node_description
)
306 EMBRACE(.name
= "dummy line handler"));
307 i9e_attach_to_stdout(dummy
);
308 ret
= i9ep
->ici
->line_handler(line
);
310 PARA_WARNING_LOG("%s\n", para_strerror(-ret
));
312 btr_remove_node(&dummy
);
317 static int i9e_post_select(__a_unused
struct sched
*s
, __a_unused
struct task
*t
)
320 struct i9e_client_info
*ici
= i9ep
->ici
;
322 size_t sz
, consumed
= 0;
327 ret
= -E_I9E_TERM_RQ
;
328 if (i9ep
->caught_sigterm
)
331 if (i9ep
->caught_sigint
)
333 while (input_available())
334 rl_callback_read_char();
335 if (!i9ep
->stdout_btrn
)
337 ret
= btr_node_status(i9ep
->stdout_btrn
, 0, BTR_NT_LEAF
);
345 sz
= btr_next_buffer(i9ep
->stdout_btrn
, &buf
);
348 if (i9ep
->last_write_was_status
)
349 fprintf(i9ep
->stderr_stream
, "\n");
350 i9ep
->last_write_was_status
= false;
351 ret
= xwrite(ici
->fds
[1], buf
, sz
);
354 btr_consume(i9ep
->stdout_btrn
, ret
);
356 if (ret
== sz
&& consumed
< 10000)
360 if (i9ep
->stdout_btrn
) {
362 btr_remove_node(&i9ep
->stdout_btrn
);
363 rl_set_keymap(i9ep
->standard_km
);
364 rl_set_prompt(i9ep
->ici
->prompt
);
370 i9ep
->caught_sigint
= false;
374 static void i9e_pre_select(struct sched
*s
, __a_unused
struct task
*t
)
378 if (i9ep
->input_eof
|| i9ep
->caught_sigint
|| i9ep
->caught_sigterm
) {
382 if (i9ep
->stdout_btrn
) {
383 ret
= btr_node_status(i9ep
->stdout_btrn
, 0, BTR_NT_LEAF
);
389 para_fd_set(i9ep
->ici
->fds
[1], &s
->wfds
, &s
->max_fileno
);
392 * fd[0] might have been reset to blocking mode if our job was moved to
393 * the background due to CTRL-Z or SIGSTOP, so set the fd back to
396 ret
= mark_fd_nonblocking(i9ep
->ici
->fds
[0]);
398 PARA_WARNING_LOG("set to nonblock failed: (fd0 %d, %s)\n",
399 i9ep
->ici
->fds
[0], para_strerror(-ret
));
400 para_fd_set(i9ep
->ici
->fds
[0], &s
->rfds
, &s
->max_fileno
);
403 static void update_winsize(void)
406 int ret
= ioctl(i9ep
->ici
->fds
[2], TIOCGWINSZ
, (char *)&w
);
409 assert(w
.ws_col
< sizeof(i9ep
->empty_line
));
410 i9ep
->num_columns
= w
.ws_col
;
412 i9ep
->num_columns
= 80;
414 memset(i9ep
->empty_line
, ' ', i9ep
->num_columns
);
415 i9ep
->empty_line
[i9ep
->num_columns
] = '\0';
419 * Defined key sequences are mapped to keys starting with this offset. I.e.
420 * pressing the first defined key sequence yields the key number \p KEY_OFFSET.
422 #define KEY_OFFSET 64
424 static int dispatch_key(__a_unused
int count
, int key
)
428 assert(key
>= KEY_OFFSET
);
429 ret
= i9ep
->ici
->key_handler(key
- KEY_OFFSET
);
430 return ret
< 0? ret
: 0;
434 * Register the i9e task and initialize readline.
436 * \param ici The i9e configuration parameters set by the caller.
437 * \param s The scheduler instance to add the i9e task to.
439 * The caller must allocate and initialize the structure \a ici points to.
443 int i9e_open(struct i9e_client_info
*ici
, struct sched
*s
)
447 if (!isatty(ici
->fds
[0]))
448 return -E_I9E_SETUPTERM
;
449 ret
= mark_fd_nonblocking(ici
->fds
[0]);
452 ret
= mark_fd_nonblocking(ici
->fds
[1]);
455 i9ep
->task
= task_register(&(struct task_info
) {
457 .pre_select
= i9e_pre_select
,
458 .post_select
= i9e_post_select
,
462 rl_readline_name
= "para_i9e";
463 rl_basic_word_break_characters
= " ";
464 rl_attempted_completion_function
= i9e_completer
;
466 i9ep
->stderr_stream
= fdopen(ici
->fds
[2], "w");
467 setvbuf(i9ep
->stderr_stream
, NULL
, _IONBF
, 0);
469 i9ep
->standard_km
= rl_get_keymap();
470 i9ep
->bare_km
= rl_make_bare_keymap();
471 if (ici
->bound_keyseqs
) {
474 /* FIXME: This is an arbitrary constant. */
475 for (i
= 0; i
< 32 && (seq
= ici
->bound_keyseqs
[i
]); i
++) {
476 char buf
[2] = {KEY_OFFSET
+ i
, '\0'};
477 /* readline needs an allocated buffer for the macro */
478 rl_generic_bind(ISMACR
, seq
, para_strdup(buf
), i9ep
->bare_km
);
479 rl_bind_key_in_map(KEY_OFFSET
+ i
, dispatch_key
, i9ep
->bare_km
);
482 if (ici
->history_file
)
483 read_history(ici
->history_file
);
486 rl_callback_handler_install("", i9e_line_handler
);
487 i9e_attach_to_stdout(ici
->producer
);
488 rl_set_keymap(i9ep
->bare_km
);
490 rl_callback_handler_install(i9ep
->ici
->prompt
, i9e_line_handler
);
494 static void reset_line_state(void)
496 if (i9ep
->stdout_btrn
)
499 rl_reset_line_state();
500 rl_forced_update_display();
504 * The log function of the i9e subsystem.
506 * \param ll Severity log level.
507 * \param fmt Printf-like format string.
509 * This clears the bottom line of the terminal if necessary and writes the
510 * string given by \a fmt to fd[2], where fd[] is the array provided earlier in
513 __printf_2_3
void i9e_log(int ll
, const char* fmt
,...)
517 if (ll
< i9ep
->ici
->loglevel
)
521 vfprintf(i9ep
->stderr_stream
, fmt
, argp
);
524 i9ep
->last_write_was_status
= false;
528 * Print the current status to stderr.
530 * \param buf The text to print.
531 * \param len The number of bytes in \a buf.
533 * This clears the bottom line, moves to the beginning of the line and prints
534 * the given text. If the length of this text exceeds the width of the
535 * terminal, the text is shortened by leaving out a part in the middle.
537 void ie9_print_status_bar(char *buf
, unsigned len
)
539 size_t x
= i9ep
->num_columns
, y
= (x
- 4) / 2;
544 fprintf(i9ep
->stderr_stream
, "\r%s", buf
);
545 fprintf(i9ep
->stderr_stream
, " .. ");
546 fprintf(i9ep
->stderr_stream
, "%s", buf
+ len
- y
);
552 strcpy(scratch
+ 1, buf
);
553 memset(scratch
+ 1 + len
, ' ', y
);
554 scratch
[1 + len
+ y
] = '\r';
555 scratch
[2 + len
+ y
] = '\0';
556 fprintf(i9ep
->stderr_stream
, "\r%s", scratch
);
558 i9ep
->last_write_was_status
= true;
562 * Tell i9e that the caller received a signal.
564 * \param sig_num The number of the signal received.
566 * Currently the function only cares about \p SIGINT, but this may change.
568 void i9e_signal_dispatch(int sig_num
)
570 if (sig_num
== SIGWINCH
)
571 return update_winsize();
572 if (sig_num
== SIGINT
) {
573 fprintf(i9ep
->stderr_stream
, "\n");
574 rl_replace_line ("", false /* clear_undo */);
576 i9ep
->caught_sigint
= true;
578 if (sig_num
== SIGTERM
)
579 i9ep
->caught_sigterm
= true;
583 * Wrapper for select(2) which does not restart on interrupts.
585 * \param n \sa \ref para_select().
586 * \param readfds \sa \ref para_select().
587 * \param writefds \sa \ref para_select().
588 * \param timeout_tv \sa \ref para_select().
590 * \return \sa \ref para_select().
592 * The only difference between this function and \ref para_select() is that
593 * \ref i9e_select() returns zero if the select call returned \p EINTR.
595 int i9e_select(int n
, fd_set
*readfds
, fd_set
*writefds
,
596 struct timeval
*timeout_tv
)
598 int ret
= select(n
, readfds
, writefds
, NULL
, timeout_tv
);
604 ret
= -ERRNO_TO_PARA_ERROR(errno
);
610 * Return the possible completions for a given word.
612 * \param word The word to complete.
613 * \param string_list All possible words in this context.
614 * \param result String list is returned here.
616 * This function never fails. If no completion was found, a string list of
617 * length zero is returned. In any case, the result must be freed by the caller
618 * using \ref free_argv().
620 * This function is independent of readline and may be called before
623 * \return The number of possible completions.
625 int i9e_extract_completions(const char *word
, char **string_list
,
628 char **matches
= para_malloc(sizeof(char *));
629 int match_count
= 0, matches_len
= 1;
631 int len
= strlen(word
);
633 for (p
= string_list
; *p
; p
++) {
634 if (!is_prefix(word
, *p
, len
))
637 if (match_count
>= matches_len
) {
639 matches
= para_realloc(matches
,
640 matches_len
* sizeof(char *));
642 matches
[match_count
- 1] = para_strdup(*p
);
644 matches
[match_count
] = NULL
;
650 * Return the list of partially matching words.
652 * \param word The command to complete.
653 * \param completers The array containing all command names.
655 * This is similar to \ref i9e_extract_completions(), but completes on the
656 * command names in \a completers.
658 * \return See \ref i9e_extract_completions().
660 char **i9e_complete_commands(const char *word
, struct i9e_completer
*completers
)
664 int i
, match_count
, len
= strlen(word
);
667 * In contrast to completing against an arbitrary string list, here we
668 * know all possible completions and expect that there will not be many
669 * of them. So it should be OK to iterate twice over all commands which
670 * simplifies the code a bit.
672 for (i
= 0, match_count
= 0; (cmd
= completers
[i
].name
); i
++) {
673 if (is_prefix(word
, cmd
, len
))
676 matches
= para_malloc((match_count
+ 1) * sizeof(*matches
));
677 for (i
= 0, match_count
= 0; (cmd
= completers
[i
].name
); i
++)
678 if (is_prefix(word
, cmd
, len
))
679 matches
[match_count
++] = para_strdup(cmd
);
680 matches
[match_count
] = NULL
;
685 * Complete according to the given options.
687 * \param opts All available options.
688 * \param ci Information which was passed to the completer.
689 * \param cr Result pointer.
691 * This convenience helper can be used to complete an option. The array of all
692 * possible options is passed as the first argument. Flags, i.e. options
693 * without an argument, are expected to be listed as strings of type "-X" in \a
694 * opts while options which require an argument should be passed with a
695 * trailing "=" character like "-X=".
697 * If the word can be uniquely completed to a flag option, an additional space
698 * character is appended to the output. For non-flag options no space character
701 void i9e_complete_option(char **opts
, struct i9e_completion_info
*ci
,
702 struct i9e_completion_result
*cr
)
706 num_matches
= i9e_extract_completions(ci
->word
, opts
, &cr
->matches
);
707 if (num_matches
== 1) {
708 char *opt
= cr
->matches
[0];
709 char c
= opt
[strlen(opt
) - 1];
711 cr
->dont_append_space
= true;
716 * Print possible completions to stdout.
718 * \param completers The array of completion functions.
720 * At the end of the output a line starting with "-o=", followed by the
721 * (possibly empty) list of completion options is printed. Currently, the only
722 * two completion options are "nospace" and "filenames". The former indicates
723 * that no space should be appended even for a unique match while the latter
724 * indicates that usual filename completion should be performed in addition to
725 * the previously printed options.
729 int i9e_print_completions(struct i9e_completer
*completers
)
731 struct i9e_completion_result cr
;
732 struct i9e_completion_info ci
;
737 reset_completion_result(&cr
);
738 buf
= getenv("COMP_POINT");
739 ci
.point
= buf
? atoi(buf
) : 0;
740 ci
.buffer
= para_strdup(getenv("COMP_LINE"));
742 ci
.argc
= create_argv(ci
.buffer
, " ", &ci
.argv
);
743 ci
.word_num
= compute_word_num(ci
.buffer
, " ", ci
.point
);
745 end
= ci
.buffer
+ ci
.point
;
746 for (p
= end
; p
> ci
.buffer
&& *p
!= ' '; p
--)
752 ci
.word
= para_malloc(n
+ 1);
753 strncpy(ci
.word
, p
, n
);
756 PARA_DEBUG_LOG("line: %s, point: %d (%c), wordnum: %d, word: %s\n",
757 ci
.buffer
, ci
.point
, ci
.buffer
[ci
.point
], ci
.word_num
, ci
.word
);
758 if (ci
.word_num
== 0)
759 cr
.matches
= i9e_complete_commands(ci
.word
, completers
);
761 create_matches(&ci
, completers
, &cr
);
763 if (cr
.matches
&& cr
.matches
[0]) {
764 for (i
= 0; cr
.matches
[i
]; i
++)
765 printf("%s\n", cr
.matches
[i
]);
769 if (cr
.dont_append_space
)
771 if (cr
.filename_completion_desired
)
772 printf(",filenames");
774 free_argv(cr
.matches
);