2 * Copyright (C) 2011-2012 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
;
30 char empty_line
[1000];
32 struct btr_node
*stdout_btrn
;
33 bool line_handler_running
;
37 static struct i9e_private i9e_private
, *i9ep
= &i9e_private
;
39 static bool is_prefix(const char *partial
, const char *full
, size_t len
)
42 len
= strlen(partial
);
43 return !strncmp(partial
, full
, len
);
47 * Generator function for command completion. STATE lets us know whether
48 * to start from scratch; without any state (i.e. STATE == 0), then we
49 * start at the top of the list.
51 static char *command_generator(const char *text
, int state
)
53 static int list_index
, len
;
55 struct i9e_client_info
*ici
= i9ep
->ici
;
57 rl_attempted_completion_over
= 1; /* disable filename completion */
59 * If this is a new word to complete, initialize now. This includes
60 * saving the length of TEXT for efficiency, and initializing the index
67 /* Return the next name which partially matches from the command list. */
68 while ((name
= ici
->completers
[list_index
].name
)) {
70 if (is_prefix(text
, name
, len
))
71 return para_strdup(name
);
73 return NULL
; /* no names matched */
76 static void reset_completion_result(struct i9e_completion_result
*cr
)
78 cr
->dont_append_space
= false;
79 cr
->filename_completion_desired
= false;
83 static void create_matches(struct i9e_completion_info
*ci
,
84 struct i9e_completer
*completers
,
85 struct i9e_completion_result
*cr
)
89 reset_completion_result(cr
);
91 ret
= create_argv(ci
->buffer
, " ", &ci
->argv
);
92 if (ret
< 0 || !ci
->argv
[0])
96 ci
->word_num
= compute_word_num(ci
->buffer
, " ", ci
->point
);
97 for (i
= 0; completers
[i
].name
; i
++) {
98 if (strcmp(completers
[i
].name
, ci
->argv
[0]) != 0)
100 completers
[i
].completer(ci
, cr
);
103 PARA_DEBUG_LOG("current word: %d (%s)\n", ci
->word_num
,
104 ci
->argv
[ci
->word_num
]);
106 for (i
= 0; cr
->matches
[i
]; i
++)
107 PARA_DEBUG_LOG("match %d: %s\n", i
, cr
->matches
[i
]);
110 static char *completion_generator(const char *word
, int state
)
112 static int list_index
;
113 static char **argv
, **matches
;
114 struct i9e_completer
*completers
= i9ep
->ici
->completers
;
115 struct i9e_completion_info ci
= {
116 .word
= (char *)word
,
118 .buffer
= rl_line_buffer
,
120 struct i9e_completion_result cr
= {.matches
= NULL
};
124 /* clean up previous matches and set defaults */
130 rl_completion_append_character
= ' ';
131 rl_completion_suppress_append
= false;
132 rl_attempted_completion_over
= true;
134 create_matches(&ci
, completers
, &cr
);
136 matches
= cr
.matches
;
138 rl_completion_suppress_append
= cr
.dont_append_space
;
139 rl_attempted_completion_over
= !cr
.filename_completion_desired
;
143 return matches
[list_index
++];
147 * Attempt to complete on the contents of TEXT. START and END bound the
148 * region of rl_line_buffer that contains the word to complete. TEXT is
149 * the word to complete. We can use the entire contents of rl_line_buffer
150 * in case we want to do some simple parsing. Return the array of matches,
151 * or NULL if there aren't any.
153 static char **i9e_completer(const char *text
, int start
, __a_unused
int end
)
155 struct i9e_client_info
*ici
= i9ep
->ici
;
157 if (!ici
->completers
)
159 /* Complete on command names if this is the first word in the line. */
161 return rl_completion_matches(text
, command_generator
);
162 return rl_completion_matches(text
, completion_generator
);
166 * Prepare writing to stdout.
168 * \param producer The buffer tree node which produces output.
170 * The i9e subsystem maintains a buffer tree node which may be attached to
171 * another node which generates output (a "producer"). When attached, the i9e
172 * buffer tree node copies the buffers generated by the producer to stdout.
174 * This function attaches the i9e input queue to an output queue of \a
179 void i9e_attach_to_stdout(struct btr_node
*producer
)
181 assert(!i9ep
->stdout_btrn
);
182 i9ep
->stdout_btrn
= btr_new_node(&(struct btr_node_description
)
183 EMBRACE(.name
= "interactive_stdout", .parent
= producer
));
187 * Reset the terminal and save the in-memory command line history.
189 * This should be called before the caller exits.
193 char *hf
= i9ep
->ici
->history_file
;
195 rl_deprep_terminal();
196 fprintf(i9ep
->stderr_stream
, "\n");
199 fclose(i9ep
->stderr_stream
);
202 static void wipe_bottom_line(void)
204 fprintf(i9ep
->stderr_stream
, "\r%s\r", i9ep
->empty_line
);
207 static void clear_bottom_line(void)
212 if (rl_point
== 0 && rl_end
== 0)
213 return wipe_bottom_line();
215 * We might have a multi-line input that needs to be wiped here, so the
216 * simple printf("\r<space>\r") is insufficient. To workaround this, we
217 * remove the whole line, redisplay and restore the killed text.
220 text
= rl_copy_text(0, rl_end
);
221 rl_kill_full_line(0, 0);
223 wipe_bottom_line(); /* wipe out the prompt */
224 rl_insert_text(text
);
228 static bool input_available(void)
231 struct timeval tv
= {0, 0};
235 FD_SET(i9ep
->ici
->fds
[0], &rfds
);
236 ret
= para_select(1, &rfds
, NULL
, &tv
);
240 static void i9e_line_handler(char *line
)
244 i9ep
->line_handler_running
= true;
245 ret
= i9ep
->ici
->line_handler(line
);
246 i9ep
->line_handler_running
= false;
248 PARA_WARNING_LOG("%s\n", para_strerror(-ret
));
252 rl_set_prompt(i9ep
->ici
->prompt
);
258 i9ep
->input_eof
= true;
262 static void i9e_input(void)
265 rl_callback_read_char();
266 } while (input_available());
269 static void i9e_post_select(struct sched
*s
, struct task
*t
)
272 struct btr_node
*btrn
= i9ep
->stdout_btrn
;
273 struct i9e_client_info
*ici
= i9ep
->ici
;
277 if (i9ep
->input_eof
) {
278 t
->error
= -E_I9E_EOF
;
282 i9ep
->caught_sigint
= false;
283 if (FD_ISSET(ici
->fds
[0], &s
->rfds
))
287 if (i9ep
->caught_sigint
)
289 ret
= btr_node_status(i9ep
->stdout_btrn
, 0, BTR_NT_LEAF
);
292 sz
= btr_next_buffer(btrn
, &buf
);
295 ret
= write_nonblock(ici
->fds
[1], buf
, sz
);
298 btr_consume(btrn
, ret
);
301 btr_remove_node(btrn
);
303 i9ep
->stdout_btrn
= NULL
;
304 rl_set_prompt(i9ep
->ici
->prompt
);
305 rl_forced_update_display();
310 static void i9e_pre_select(struct sched
*s
, __a_unused
struct task
*t
)
314 if (i9ep
->input_eof
|| i9ep
->caught_sigint
) {
318 if (i9ep
->stdout_btrn
) {
319 ret
= btr_node_status(i9ep
->stdout_btrn
, 0, BTR_NT_LEAF
);
325 para_fd_set(i9ep
->ici
->fds
[1], &s
->wfds
, &s
->max_fileno
);
328 * fd[0] might have been reset to blocking mode if our job was moved to
329 * the background due to CTRL-Z or SIGSTOP, so set the fd back to
332 ret
= mark_fd_nonblocking(i9ep
->ici
->fds
[0]);
334 PARA_WARNING_LOG("set to nonblock failed: (fd0 %d, %s)\n",
335 i9ep
->ici
->fds
[0], para_strerror(-ret
));
336 para_fd_set(i9ep
->ici
->fds
[0], &s
->rfds
, &s
->max_fileno
);
340 static void update_winsize(void)
343 int ret
= ioctl(i9ep
->ici
->fds
[2], TIOCGWINSZ
, (char *)&w
);
344 int num_columns
= 80;
347 assert(w
.ws_col
< sizeof(i9ep
->empty_line
));
348 num_columns
= w
.ws_col
;
350 memset(i9ep
->empty_line
, ' ', num_columns
);
351 i9ep
->empty_line
[num_columns
] = '\0';
355 * Register the i9e task and initialize readline.
357 * \param ici The i9e configuration parameters set by the caller.
358 * \param s The scheduler instance to add the i9e task to.
360 * The caller must allocate and initialize the structure \a ici points to.
363 * \sa \ref register_task().
365 int i9e_open(struct i9e_client_info
*ici
, struct sched
*s
)
369 if (!isatty(ici
->fds
[0]))
370 return -E_I9E_SETUPTERM
;
371 ret
= mark_fd_nonblocking(ici
->fds
[0]);
374 ret
= mark_fd_nonblocking(ici
->fds
[1]);
377 i9ep
->task
.pre_select
= i9e_pre_select
;
378 i9ep
->task
.post_select
= i9e_post_select
;
379 register_task(s
, &i9ep
->task
);
380 rl_readline_name
= "para_i9e";
381 rl_basic_word_break_characters
= " ";
382 rl_attempted_completion_function
= i9e_completer
;
384 i9ep
->stderr_stream
= fdopen(ici
->fds
[2], "w");
386 if (ici
->history_file
)
387 read_history(ici
->history_file
);
389 rl_callback_handler_install(i9ep
->ici
->prompt
, i9e_line_handler
);
393 static void reset_line_state(void)
395 if (i9ep
->line_handler_running
)
398 rl_reset_line_state();
399 rl_forced_update_display();
403 * The log function of the i9e subsystem.
405 * \param ll Severity log level.
406 * \param fmt Printf-like format string.
408 * This clears the bottom line of the terminal if necessary and writes the
409 * string given by \a fmt to fd[2], where fd[] is the array provided earlier in
412 __printf_2_3
void i9e_log(int ll
, const char* fmt
,...)
416 if (ll
< i9ep
->ici
->loglevel
)
418 if (i9ep
->line_handler_running
== false)
421 vfprintf(i9ep
->stderr_stream
, fmt
, argp
);
427 * Tell i9e that the caller received a signal.
429 * \param sig_num The number of the signal received.
431 * Currently the function only cares about \p SIGINT, but this may change.
433 void i9e_signal_dispatch(int sig_num
)
435 if (sig_num
== SIGINT
) {
436 fprintf(i9ep
->stderr_stream
, "\n");
437 rl_replace_line ("", false /* clear_undo */);
439 i9ep
->caught_sigint
= true;
444 * Wrapper for select(2) which does not restart on interrupts.
446 * \param n \sa \ref para_select().
447 * \param readfds \sa \ref para_select().
448 * \param writefds \sa \ref para_select().
449 * \param timeout_tv \sa \ref para_select().
451 * \return \sa \ref para_select().
453 * The only difference between this function and \ref para_select() is that
454 * \ref i9e_select() returns zero if the select call returned \p EINTR.
456 int i9e_select(int n
, fd_set
*readfds
, fd_set
*writefds
,
457 struct timeval
*timeout_tv
)
459 int ret
= select(n
, readfds
, writefds
, NULL
, timeout_tv
);
465 ret
= -ERRNO_TO_PARA_ERROR(errno
);
471 * Return the possible completions for a given word.
473 * \param word The word to complete.
474 * \param string_list All possible words in this context.
475 * \param result String list is returned here.
477 * This function never fails. If no completion was found, a string list of
478 * length zero is returned. In any case, the result must be freed by the caller
479 * using \ref free_argv().
481 * This function is independent of readline and may be called before
484 * \return The number of possible completions.
486 int i9e_extract_completions(const char *word
, char **string_list
,
489 char **matches
= para_malloc(sizeof(char *));
490 int match_count
= 0, matches_len
= 1;
492 int len
= strlen(word
);
494 for (p
= string_list
; *p
; p
++) {
495 if (!is_prefix(word
, *p
, len
))
498 if (match_count
>= matches_len
) {
500 matches
= para_realloc(matches
,
501 matches_len
* sizeof(char *));
503 matches
[match_count
- 1] = para_strdup(*p
);
505 matches
[match_count
] = NULL
;
511 * Return the list of partially matching words.
513 * \param word The command to complete.
514 * \param completers The array containing all command names.
516 * This is similar to \ref i9e_extract_completions(), but completes on the
517 * command names in \a completers.
519 * \return See \ref i9e_extract_completions().
521 char **i9e_complete_commands(const char *word
, struct i9e_completer
*completers
)
525 int i
, match_count
, len
= strlen(word
);
528 * In contrast to completing against an arbitrary string list, here we
529 * know all possible completions and expect that there will not be many
530 * of them. So it should be OK to iterate twice over all commands which
531 * simplifies the code a bit.
533 for (i
= 0, match_count
= 0; (cmd
= completers
[i
].name
); i
++) {
534 if (is_prefix(word
, cmd
, len
))
537 matches
= para_malloc((match_count
+ 1) * sizeof(*matches
));
538 for (i
= 0, match_count
= 0; (cmd
= completers
[i
].name
); i
++)
539 if (is_prefix(word
, cmd
, len
))
540 matches
[match_count
++] = para_strdup(cmd
);
541 matches
[match_count
] = NULL
;
546 * Complete according to the given options.
548 * \param opts All available options.
549 * \param ci Information which was passed to the completer.
550 * \param cr Result pointer.
552 * This convenience helper can be used to complete an option. The array of all
553 * possible options is passed as the first argument. Flags, i.e. options
554 * without an argument, are expected to be listed as strings of type "-X" in \a
555 * opts while options which require an argument should be passed with a
556 * trailing "=" character like "-X=".
558 * If the word can be uniquely completed to a flag option, an additional space
559 * character is appended to the output. For non-flag options no space character
562 void i9e_complete_option(char **opts
, struct i9e_completion_info
*ci
,
563 struct i9e_completion_result
*cr
)
567 num_matches
= i9e_extract_completions(ci
->word
, opts
, &cr
->matches
);
568 if (num_matches
== 1) {
569 char *opt
= cr
->matches
[0];
570 char c
= opt
[strlen(opt
) - 1];
572 cr
->dont_append_space
= true;
577 * Print possible completions to stdout.
579 * \param completers The array of completion functions.
581 * At the end of the output a line starting with "-o=", followed by the
582 * (possibly empty) list of completion options is printed. Currently, the only
583 * two completion options are "nospace" and "filenames". The former indicates
584 * that no space should be appended even for a unique match while the latter
585 * indicates that usual filename completion should be performed in addition to
586 * the previously printed options.
590 int i9e_print_completions(struct i9e_completer
*completers
)
592 struct i9e_completion_result cr
;
593 struct i9e_completion_info ci
;
598 reset_completion_result(&cr
);
599 buf
= getenv("COMP_POINT");
600 ci
.point
= buf
? atoi(buf
) : 0;
601 ci
.buffer
= para_strdup(getenv("COMP_LINE"));
603 ci
.argc
= create_argv(ci
.buffer
, " ", &ci
.argv
);
604 ci
.word_num
= compute_word_num(ci
.buffer
, " ", ci
.point
);
606 end
= ci
.buffer
+ ci
.point
;
607 for (p
= end
; p
> ci
.buffer
&& *p
!= ' '; p
--)
613 ci
.word
= para_malloc(n
+ 1);
614 strncpy(ci
.word
, p
, n
);
617 PARA_DEBUG_LOG("line: %s, point: %d (%c), wordnum: %d, word: %s\n",
618 ci
.buffer
, ci
.point
, ci
.buffer
[ci
.point
], ci
.word_num
, ci
.word
);
619 if (ci
.word_num
== 0)
620 cr
.matches
= i9e_complete_commands(ci
.word
, completers
);
622 create_matches(&ci
, completers
, &cr
);
624 if (cr
.matches
&& cr
.matches
[0]) {
625 for (i
= 0; cr
.matches
[i
]; i
++)
626 printf("%s\n", cr
.matches
[i
]);
630 if (cr
.dont_append_space
)
632 if (cr
.filename_completion_desired
)
633 printf(",filenames");
635 free_argv(cr
.matches
);