1 /* callback.c -- functions to use readline as an X `callback' mechanism. */
3 /* Copyright (C) 1987-2015 Free Software Foundation, Inc.
5 This file is part of the GNU Readline Library (Readline), a library
6 for reading lines of text with interactive input and history editing.
8 Readline is free software: you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation, either version 3 of the License, or
11 (at your option) any later version.
13 Readline is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with Readline. If not, see <http://www.gnu.org/licenses/>.
22 #define READLINE_LIBRARY
24 #if defined (HAVE_CONFIG_H)
30 #if defined (READLINE_CALLBACKS)
32 #include <sys/types.h>
37 # include "ansi_stdlib.h"
42 /* System-specific feature definitions and include files. */
45 #include "rlprivate.h"
48 /* Private data for callback registration functions. See comments in
49 rl_callback_read_char for more details. */
50 _rl_callback_func_t
*_rl_callback_func
= 0;
51 _rl_callback_generic_arg
*_rl_callback_data
= 0;
53 /* Applications can set this to non-zero to have readline's signal handlers
54 installed during the entire duration of reading a complete line, as in
55 readline-6.2. This should be used with care, because it can result in
56 readline receiving signals and not handling them until it's called again
57 via rl_callback_read_char, thereby stealing them from the application.
58 By default, signal handlers are only active while readline is active. */
59 int rl_persistent_signal_handlers
= 0;
61 /* **************************************************************** */
63 /* Callback Readline Functions */
65 /* **************************************************************** */
67 /* Allow using readline in situations where a program may have multiple
68 things to handle at once, and dispatches them via select(). Call
69 rl_callback_handler_install() with the prompt and a function to call
70 whenever a complete line of input is ready. The user must then
71 call rl_callback_read_char() every time some input is available, and
72 rl_callback_read_char() will call the user's function with the complete
73 text read in at each end of line. The terminal is kept prepped
74 all the time, except during calls to the user's function. Signal
75 handlers are only installed when the application calls back into
76 readline, so readline doesn't `steal' signals from the application. */
78 rl_vcpfunc_t
*rl_linefunc
; /* user callback function */
79 static int in_handler
; /* terminal_prepped and signals set? */
81 /* Make sure the terminal is set up, initialize readline, and prompt. */
83 _rl_callback_newline ()
91 if (rl_prep_term_function
)
92 (*rl_prep_term_function
) (_rl_meta_flag
);
94 #if defined (HANDLE_SIGNALS)
95 if (rl_persistent_signal_handlers
)
100 readline_internal_setup ();
104 /* Install a readline handler, set up the terminal, and issue the prompt. */
106 rl_callback_handler_install (prompt
, linefunc
)
108 rl_vcpfunc_t
*linefunc
;
110 rl_set_prompt (prompt
);
111 RL_SETSTATE (RL_STATE_CALLBACK
);
112 rl_linefunc
= linefunc
;
113 _rl_callback_newline ();
116 #if defined (HANDLE_SIGNALS)
117 #define CALLBACK_READ_RETURN() \
119 if (rl_persistent_signal_handlers == 0) \
120 rl_clear_signals (); \
124 #define CALLBACK_READ_RETURN() return
127 /* Read one character, and dispatch to the handler if it ends the line. */
129 rl_callback_read_char ()
133 static procenv_t olevel
;
135 if (rl_linefunc
== NULL
)
137 _rl_errmsg ("readline_callback_read_char() called with no handler!");
141 memcpy ((void *)olevel
, (void *)_rl_top_level
, sizeof (procenv_t
));
142 #if defined (HAVE_POSIX_SIGSETJMP)
143 jcode
= sigsetjmp (_rl_top_level
, 0);
145 jcode
= setjmp (_rl_top_level
);
149 (*rl_redisplay_function
) ();
150 _rl_want_redisplay
= 0;
151 memcpy ((void *)_rl_top_level
, (void *)olevel
, sizeof (procenv_t
));
152 CALLBACK_READ_RETURN ();
155 #if defined (HANDLE_SIGNALS)
156 /* Install signal handlers only when readline has control. */
157 if (rl_persistent_signal_handlers
== 0)
164 if (RL_ISSTATE (RL_STATE_ISEARCH
))
166 eof
= _rl_isearch_callback (_rl_iscxt
);
167 if (eof
== 0 && (RL_ISSTATE (RL_STATE_ISEARCH
) == 0) && RL_ISSTATE (RL_STATE_INPUTPENDING
))
168 rl_callback_read_char ();
170 CALLBACK_READ_RETURN ();
172 else if (RL_ISSTATE (RL_STATE_NSEARCH
))
174 eof
= _rl_nsearch_callback (_rl_nscxt
);
176 CALLBACK_READ_RETURN ();
178 #if defined (VI_MODE)
179 /* States that can occur while in state VIMOTION have to be checked
180 before RL_STATE_VIMOTION */
181 else if (RL_ISSTATE (RL_STATE_CHARSEARCH
))
185 k
= _rl_callback_data
->i2
;
187 eof
= (*_rl_callback_func
) (_rl_callback_data
);
188 /* If the function `deregisters' itself, make sure the data is
190 if (_rl_callback_func
== 0) /* XXX - just sanity check */
192 if (_rl_callback_data
)
194 _rl_callback_data_dispose (_rl_callback_data
);
195 _rl_callback_data
= 0;
199 /* Messy case where vi motion command can be char search */
200 if (RL_ISSTATE (RL_STATE_VIMOTION
))
202 _rl_vi_domove_motion_cleanup (k
, _rl_vimvcxt
);
203 _rl_internal_char_cleanup ();
204 CALLBACK_READ_RETURN ();
207 _rl_internal_char_cleanup ();
209 else if (RL_ISSTATE (RL_STATE_VIMOTION
))
211 eof
= _rl_vi_domove_callback (_rl_vimvcxt
);
212 /* Should handle everything, including cleanup, numeric arguments,
213 and turning off RL_STATE_VIMOTION */
214 if (RL_ISSTATE (RL_STATE_NUMERICARG
) == 0)
215 _rl_internal_char_cleanup ();
217 CALLBACK_READ_RETURN ();
220 else if (RL_ISSTATE (RL_STATE_NUMERICARG
))
222 eof
= _rl_arg_callback (_rl_argcxt
);
223 if (eof
== 0 && (RL_ISSTATE (RL_STATE_NUMERICARG
) == 0) && RL_ISSTATE (RL_STATE_INPUTPENDING
))
224 rl_callback_read_char ();
225 /* XXX - this should handle _rl_last_command_was_kill better */
226 else if (RL_ISSTATE (RL_STATE_NUMERICARG
) == 0)
227 _rl_internal_char_cleanup ();
229 CALLBACK_READ_RETURN ();
231 else if (RL_ISSTATE (RL_STATE_MULTIKEY
))
233 eof
= _rl_dispatch_callback (_rl_kscxt
); /* For now */
234 while ((eof
== -1 || eof
== -2) && RL_ISSTATE (RL_STATE_MULTIKEY
) && _rl_kscxt
&& (_rl_kscxt
->flags
& KSEQ_DISPATCHED
))
235 eof
= _rl_dispatch_callback (_rl_kscxt
);
236 if (RL_ISSTATE (RL_STATE_MULTIKEY
) == 0)
238 _rl_internal_char_cleanup ();
239 _rl_want_redisplay
= 1;
242 else if (_rl_callback_func
)
244 /* This allows functions that simply need to read an additional
245 character (like quoted-insert) to register a function to be
246 called when input is available. _rl_callback_data is a
247 pointer to a struct that has the argument count originally
248 passed to the registering function and space for any additional
250 eof
= (*_rl_callback_func
) (_rl_callback_data
);
251 /* If the function `deregisters' itself, make sure the data is
253 if (_rl_callback_func
== 0)
255 if (_rl_callback_data
)
257 _rl_callback_data_dispose (_rl_callback_data
);
258 _rl_callback_data
= 0;
260 _rl_internal_char_cleanup ();
264 eof
= readline_internal_char ();
267 if (rl_done
== 0 && _rl_want_redisplay
)
269 (*rl_redisplay_function
) ();
270 _rl_want_redisplay
= 0;
275 line
= readline_internal_teardown (eof
);
277 if (rl_deprep_term_function
)
278 (*rl_deprep_term_function
) ();
279 #if defined (HANDLE_SIGNALS)
283 (*rl_linefunc
) (line
);
285 /* If the user did not clear out the line, do it for him. */
286 if (rl_line_buffer
[0])
287 _rl_init_line_state ();
289 /* Redisplay the prompt if readline_handler_{install,remove}
291 if (in_handler
== 0 && rl_linefunc
)
292 _rl_callback_newline ();
295 while (rl_pending_input
|| _rl_pushed_input_available () || RL_ISSTATE (RL_STATE_MACROINPUT
));
297 CALLBACK_READ_RETURN ();
300 /* Remove the handler, and make sure the terminal is in its normal state. */
302 rl_callback_handler_remove ()
305 RL_UNSETSTATE (RL_STATE_CALLBACK
);
310 if (rl_deprep_term_function
)
311 (*rl_deprep_term_function
) ();
312 #if defined (HANDLE_SIGNALS)
318 _rl_callback_generic_arg
*
319 _rl_callback_data_alloc (count
)
322 _rl_callback_generic_arg
*arg
;
324 arg
= (_rl_callback_generic_arg
*)xmalloc (sizeof (_rl_callback_generic_arg
));
327 arg
->i1
= arg
->i2
= 0;
333 _rl_callback_data_dispose (arg
)
334 _rl_callback_generic_arg
*arg
;
339 /* Make sure that this agrees with cases in rl_callback_read_char */
341 rl_callback_sigcleanup ()
343 if (RL_ISSTATE (RL_STATE_CALLBACK
) == 0)
346 if (RL_ISSTATE (RL_STATE_ISEARCH
))
347 _rl_isearch_cleanup (_rl_iscxt
, 0);
348 else if (RL_ISSTATE (RL_STATE_NSEARCH
))
349 _rl_nsearch_cleanup (_rl_nscxt
, 0);
350 else if (RL_ISSTATE (RL_STATE_VIMOTION
))
351 RL_UNSETSTATE (RL_STATE_VIMOTION
);
352 else if (RL_ISSTATE (RL_STATE_NUMERICARG
))
355 RL_UNSETSTATE (RL_STATE_NUMERICARG
);
357 else if (RL_ISSTATE (RL_STATE_MULTIKEY
))
358 RL_UNSETSTATE (RL_STATE_MULTIKEY
);
359 if (RL_ISSTATE (RL_STATE_CHARSEARCH
))
360 RL_UNSETSTATE (RL_STATE_CHARSEARCH
);
362 _rl_callback_func
= 0;