1/* callback.c -- functions to use readline as an X `callback' mechanism. */
2
3/* Copyright (C) 1987-2005 Free Software Foundation, Inc.
4
5 This file is part of the GNU Readline Library, a library for
6 reading lines of text with interactive input and history editing.
7
8 The GNU Readline Library is free software; you can redistribute it
9 and/or modify it under the terms of the GNU General Public License
10 as published by the Free Software Foundation; either version 2, or
11 (at your option) any later version.
12
13 The GNU Readline Library is distributed in the hope that it will be
14 useful, but WITHOUT ANY WARRANTY; without even the implied warranty
15 of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
17
18 The GNU General Public License is often shipped with GNU software, and
19 is generally kept in a file called COPYING or LICENSE. If you do not
20 have a copy of the license, write to the Free Software Foundation,
21 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */
22#define READLINE_LIBRARY
23
24#if defined (HAVE_CONFIG_H)
25# include "config_readline.h"
26#endif
27
28#include "rlconf.h"
29
30#if defined (READLINE_CALLBACKS)
31
32#include <sys/types.h>
33
34#ifdef HAVE_STDLIB_H
35# include <stdlib.h>
36#else
37# include "ansi_stdlib.h"
38#endif
39
40#include <stdio.h>
41
42/* System-specific feature definitions and include files. */
43#include "rldefs.h"
44#include "readline.h"
45#include "rlprivate.h"
46#include "xmalloc.h"
47
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;
52
53/* **************************************************************** */
54/* */
55/* Callback Readline Functions */
56/* */
57/* **************************************************************** */
58
59/* Allow using readline in situations where a program may have multiple
60 things to handle at once, and dispatches them via select(). Call
61 rl_callback_handler_install() with the prompt and a function to call
62 whenever a complete line of input is ready. The user must then
63 call rl_callback_read_char() every time some input is available, and
64 rl_callback_read_char() will call the user's function with the complete
65 text read in at each end of line. The terminal is kept prepped and
66 signals handled all the time, except during calls to the user's function. */
67
68rl_vcpfunc_t *rl_linefunc; /* user callback function */
69static int in_handler; /* terminal_prepped and signals set? */
70
71/* Make sure the terminal is set up, initialize readline, and prompt. */
72static void
73_rl_callback_newline ()
74{
75 rl_initialize ();
76
77 if (in_handler == 0)
78 {
79 in_handler = 1;
80
81 if (rl_prep_term_function)
82 (*rl_prep_term_function) (_rl_meta_flag);
83
84#if defined (HANDLE_SIGNALS)
85 rl_set_signals ();
86#endif
87 }
88
89 readline_internal_setup ();
90}
91
92/* Install a readline handler, set up the terminal, and issue the prompt. */
93void
94rl_callback_handler_install (prompt, linefunc)
95 const char *prompt;
96 rl_vcpfunc_t *linefunc;
97{
98 rl_set_prompt (prompt);
99 RL_SETSTATE (RL_STATE_CALLBACK);
100 rl_linefunc = linefunc;
101 _rl_callback_newline ();
102}
103
104/* Read one character, and dispatch to the handler if it ends the line. */
105void
106rl_callback_read_char ()
107{
108 char *line;
109 int eof, jcode;
110 static procenv_t olevel;
111
112 if (rl_linefunc == NULL)
113 {
114 fprintf (stderr, "readline: readline_callback_read_char() called with no handler!\r\n");
115 abort ();
116 }
117
118 memcpy ((void *)olevel, (void *)readline_top_level, sizeof (procenv_t));
119 jcode = setjmp (readline_top_level);
120 if (jcode)
121 {
122 (*rl_redisplay_function) ();
123 _rl_want_redisplay = 0;
124 memcpy ((void *)readline_top_level, (void *)olevel, sizeof (procenv_t));
125 return;
126 }
127
128 do
129 {
130 if (RL_ISSTATE (RL_STATE_ISEARCH))
131 {
132 eof = _rl_isearch_callback (_rl_iscxt);
133 if (eof == 0 && (RL_ISSTATE (RL_STATE_ISEARCH) == 0) && RL_ISSTATE (RL_STATE_INPUTPENDING))
134 rl_callback_read_char ();
135
136 return;
137 }
138 else if (RL_ISSTATE (RL_STATE_NSEARCH))
139 {
140 eof = _rl_nsearch_callback (_rl_nscxt);
141 return;
142 }
143 else if (RL_ISSTATE (RL_STATE_NUMERICARG))
144 {
145 eof = _rl_arg_callback (_rl_argcxt);
146 if (eof == 0 && (RL_ISSTATE (RL_STATE_NUMERICARG) == 0) && RL_ISSTATE (RL_STATE_INPUTPENDING))
147 rl_callback_read_char ();
148 /* XXX - this should handle _rl_last_command_was_kill better */
149 else if (RL_ISSTATE (RL_STATE_NUMERICARG) == 0)
150 _rl_internal_char_cleanup ();
151
152 return;
153 }
154 else if (RL_ISSTATE (RL_STATE_MULTIKEY))
155 {
156 eof = _rl_dispatch_callback (_rl_kscxt); /* For now */
157 while ((eof == -1 || eof == -2) && RL_ISSTATE (RL_STATE_MULTIKEY) && _rl_kscxt && (_rl_kscxt->flags & KSEQ_DISPATCHED))
158 eof = _rl_dispatch_callback (_rl_kscxt);
159 if (RL_ISSTATE (RL_STATE_MULTIKEY) == 0)
160 {
161 _rl_internal_char_cleanup ();
162 _rl_want_redisplay = 1;
163 }
164 }
165 else if (_rl_callback_func)
166 {
167 /* This allows functions that simply need to read an additional
168 character (like quoted-insert) to register a function to be
169 called when input is available. _rl_callback_data is simply a
170 pointer to a struct that has the argument count originally
171 passed to the registering function and space for any additional
172 parameters. */
173 eof = (*_rl_callback_func) (_rl_callback_data);
174 /* If the function `deregisters' itself, make sure the data is
175 cleaned up. */
176 if (_rl_callback_func == 0)
177 {
178 if (_rl_callback_data)
179 {
180 _rl_callback_data_dispose (_rl_callback_data);
181 _rl_callback_data = 0;
182 }
183 _rl_internal_char_cleanup ();
184 }
185 }
186 else
187 eof = readline_internal_char ();
188
189 if (rl_done == 0 && _rl_want_redisplay)
190 {
191 (*rl_redisplay_function) ();
192 _rl_want_redisplay = 0;
193 }
194
195 if (rl_done)
196 {
197 line = readline_internal_teardown (eof);
198
199 if (rl_deprep_term_function)
200 (*rl_deprep_term_function) ();
201#if defined (HANDLE_SIGNALS)
202 rl_clear_signals ();
203#endif
204 in_handler = 0;
205 (*rl_linefunc) (line);
206
207 /* If the user did not clear out the line, do it for him. */
208 if (rl_line_buffer[0])
209 _rl_init_line_state ();
210
211 /* Redisplay the prompt if readline_handler_{install,remove}
212 not called. */
213 if (in_handler == 0 && rl_linefunc)
214 _rl_callback_newline ();
215 }
216 }
217 while (rl_pending_input || _rl_pushed_input_available () || RL_ISSTATE (RL_STATE_MACROINPUT));
218}
219
220/* Remove the handler, and make sure the terminal is in its normal state. */
221void
222rl_callback_handler_remove ()
223{
224 rl_linefunc = NULL;
225 RL_UNSETSTATE (RL_STATE_CALLBACK);
226 if (in_handler)
227 {
228 in_handler = 0;
229 if (rl_deprep_term_function)
230 (*rl_deprep_term_function) ();
231#if defined (HANDLE_SIGNALS)
232 rl_clear_signals ();
233#endif
234 }
235}
236
237_rl_callback_generic_arg *
238_rl_callback_data_alloc (count)
239 int count;
240{
241 _rl_callback_generic_arg *arg;
242
243 arg = (_rl_callback_generic_arg *)xmalloc (sizeof (_rl_callback_generic_arg));
244 arg->count = count;
245
246 arg->i1 = arg->i2 = 0;
247
248 return arg;
249}
250
251void _rl_callback_data_dispose (arg)
252 _rl_callback_generic_arg *arg;
253{
254 if (arg)
255 free (arg);
256}
257
258#endif
259