1 /* Copyright (C) 1995,1996,1998,1999,2000,2001, 2003, 2006, 2008 Free Software Foundation, Inc.
3 * This library is free software; you can redistribute it and/or
4 * modify it under the terms of the GNU Lesser General Public
5 * License as published by the Free Software Foundation; either
6 * version 2.1 of the License, or (at your option) any later version.
8 * This library is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 * Lesser General Public License for more details.
13 * You should have received a copy of the GNU Lesser General Public
14 * License along with this library; if not, write to the Free Software
15 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
25 #include "libguile/_scm.h"
27 #include "libguile/eval.h"
28 #include "libguile/ports.h"
29 #include "libguile/procprop.h"
30 #include "libguile/root.h"
31 #include "libguile/smob.h"
32 #include "libguile/strings.h"
34 #include "libguile/validate.h"
35 #include "libguile/hooks.h"
40 * Currently, this implementation is separate from the Scheme level
41 * hooks. The possibility exists to implement the Scheme level hooks
42 * using C level hooks.
46 scm_c_hook_init (scm_t_c_hook *hook, void *hook_data, scm_t_c_hook_type type)
50 hook->data = hook_data;
54 scm_c_hook_add (scm_t_c_hook *hook,
55 scm_t_c_hook_function func,
59 scm_t_c_hook_entry *entry = scm_malloc (sizeof (scm_t_c_hook_entry));
60 scm_t_c_hook_entry **loc = &hook->first;
66 entry->data = fn_data;
71 scm_c_hook_remove (scm_t_c_hook *hook,
72 scm_t_c_hook_function func,
75 scm_t_c_hook_entry **loc = &hook->first;
78 if ((*loc)->func == func && (*loc)->data == fn_data)
80 scm_t_c_hook_entry *entry = *loc;
87 fprintf (stderr, "Attempt to remove non-existent hook function\n");
92 scm_c_hook_run (scm_t_c_hook *hook, void *data)
94 scm_t_c_hook_entry *entry = hook->first;
95 scm_t_c_hook_type type = hook->type;
99 res = (entry->func) (hook->data, entry->data, data);
102 if (type == SCM_C_HOOK_OR)
107 if (type == SCM_C_HOOK_AND)
116 /* Scheme level hooks
118 * A hook is basically a list of procedures to be called at well defined
121 * Hook arity is not a full member of this type and therefore lacks an
122 * accessor. It exists to aid debugging and is not intended to be used in
126 scm_t_bits scm_tc16_hook;
130 hook_print (SCM hook, SCM port, scm_print_state *pstate)
133 scm_puts ("#<hook ", port);
134 scm_intprint (SCM_HOOK_ARITY (hook), 10, port);
135 scm_putc (' ', port);
136 scm_uintprint (SCM_UNPACK (hook), 16, port);
137 ls = SCM_HOOK_PROCEDURES (hook);
138 while (SCM_NIMP (ls))
140 scm_putc (' ', port);
141 name = scm_procedure_name (SCM_CAR (ls));
142 if (scm_is_true (name))
143 scm_iprin1 (name, port, pstate);
145 scm_putc ('?', port);
148 scm_putc ('>', port);
153 SCM_DEFINE (scm_make_hook, "make-hook", 0, 1, 0,
155 "Create a hook for storing procedure of arity @var{n_args}.\n"
156 "@var{n_args} defaults to zero. The returned value is a hook\n"
157 "object to be used with the other hook procedures.")
158 #define FUNC_NAME s_scm_make_hook
162 if (SCM_UNBNDP (n_args))
165 n = scm_to_unsigned_integer (n_args, 0, 16);
167 SCM_RETURN_NEWSMOB (scm_tc16_hook + (n << 16), SCM_UNPACK (SCM_EOL));
172 SCM_DEFINE (scm_hook_p, "hook?", 1, 0, 0,
174 "Return @code{#t} if @var{x} is a hook, @code{#f} otherwise.")
175 #define FUNC_NAME s_scm_hook_p
177 return scm_from_bool (SCM_HOOKP (x));
182 SCM_DEFINE (scm_hook_empty_p, "hook-empty?", 1, 0, 0,
184 "Return @code{#t} if @var{hook} is an empty hook, @code{#f}\n"
186 #define FUNC_NAME s_scm_hook_empty_p
188 SCM_VALIDATE_HOOK (1, hook);
189 return scm_from_bool (scm_is_null (SCM_HOOK_PROCEDURES (hook)));
194 SCM_DEFINE (scm_add_hook_x, "add-hook!", 2, 1, 0,
195 (SCM hook, SCM proc, SCM append_p),
196 "Add the procedure @var{proc} to the hook @var{hook}. The\n"
197 "procedure is added to the end if @var{append_p} is true,\n"
198 "otherwise it is added to the front. The return value of this\n"
199 "procedure is not specified.")
200 #define FUNC_NAME s_scm_add_hook_x
204 SCM_VALIDATE_HOOK (1, hook);
205 SCM_ASSERT (scm_is_true (arity = scm_i_procedure_arity (proc)),
206 proc, SCM_ARG2, FUNC_NAME);
207 n_args = SCM_HOOK_ARITY (hook);
208 if (scm_to_int (SCM_CAR (arity)) > n_args
209 || (scm_is_false (SCM_CADDR (arity))
210 && (scm_to_int (SCM_CAR (arity)) + scm_to_int (SCM_CADR (arity))
212 scm_wrong_type_arg (FUNC_NAME, 2, proc);
213 rest = scm_delq_x (proc, SCM_HOOK_PROCEDURES (hook));
214 SCM_SET_HOOK_PROCEDURES (hook,
215 (!SCM_UNBNDP (append_p) && scm_is_true (append_p)
216 ? scm_append_x (scm_list_2 (rest, scm_list_1 (proc)))
217 : scm_cons (proc, rest)));
218 return SCM_UNSPECIFIED;
223 SCM_DEFINE (scm_remove_hook_x, "remove-hook!", 2, 0, 0,
224 (SCM hook, SCM proc),
225 "Remove the procedure @var{proc} from the hook @var{hook}. The\n"
226 "return value of this procedure is not specified.")
227 #define FUNC_NAME s_scm_remove_hook_x
229 SCM_VALIDATE_HOOK (1, hook);
230 SCM_SET_HOOK_PROCEDURES (hook,
231 scm_delq_x (proc, SCM_HOOK_PROCEDURES (hook)));
232 return SCM_UNSPECIFIED;
237 SCM_DEFINE (scm_reset_hook_x, "reset-hook!", 1, 0, 0,
239 "Remove all procedures from the hook @var{hook}. The return\n"
240 "value of this procedure is not specified.")
241 #define FUNC_NAME s_scm_reset_hook_x
243 SCM_VALIDATE_HOOK (1, hook);
244 SCM_SET_HOOK_PROCEDURES (hook, SCM_EOL);
245 return SCM_UNSPECIFIED;
250 SCM_DEFINE (scm_run_hook, "run-hook", 1, 0, 1,
251 (SCM hook, SCM args),
252 "Apply all procedures from the hook @var{hook} to the arguments\n"
253 "@var{args}. The order of the procedure application is first to\n"
254 "last. The return value of this procedure is not specified.")
255 #define FUNC_NAME s_scm_run_hook
257 SCM_VALIDATE_HOOK (1, hook);
258 if (scm_ilength (args) != SCM_HOOK_ARITY (hook))
259 SCM_MISC_ERROR ("Hook ~S requires ~A arguments",
260 scm_list_2 (hook, scm_from_int (SCM_HOOK_ARITY (hook))));
261 scm_c_run_hook (hook, args);
262 return SCM_UNSPECIFIED;
268 scm_c_run_hook (SCM hook, SCM args)
270 SCM procs = SCM_HOOK_PROCEDURES (hook);
271 while (SCM_NIMP (procs))
273 scm_apply_0 (SCM_CAR (procs), args);
274 procs = SCM_CDR (procs);
279 SCM_DEFINE (scm_hook_to_list, "hook->list", 1, 0, 0,
281 "Convert the procedure list of @var{hook} to a list.")
282 #define FUNC_NAME s_scm_hook_to_list
284 SCM_VALIDATE_HOOK (1, hook);
285 return scm_list_copy (SCM_HOOK_PROCEDURES (hook));
295 scm_tc16_hook = scm_make_smob_type ("hook", 0);
296 scm_set_smob_mark (scm_tc16_hook, scm_markcdr);
297 scm_set_smob_print (scm_tc16_hook, hook_print);
298 #include "libguile/hooks.x"