--- /dev/null
+/* Copyright (C) 1995,1996,1998,1999,2000,2001, 2003, 2006, 2008 Free Software Foundation, Inc.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+
+\f
+#ifdef HAVE_CONFIG_H
+# include <config.h>
+#endif
+
+#include <stdio.h>
+#include "libguile/_scm.h"
+
+#include "libguile/eval.h"
+#include "libguile/ports.h"
+#include "libguile/procprop.h"
+#include "libguile/root.h"
+#include "libguile/smob.h"
+#include "libguile/strings.h"
+
+#include "libguile/validate.h"
+#include "libguile/hooks.h"
+
+\f
+/* C level hooks
+ *
+ * Currently, this implementation is separate from the Scheme level
+ * hooks. The possibility exists to implement the Scheme level hooks
+ * using C level hooks.
+ */
+
+void
+scm_c_hook_init (scm_t_c_hook *hook, void *hook_data, scm_t_c_hook_type type)
+{
+ hook->first = 0;
+ hook->type = type;
+ hook->data = hook_data;
+}
+
+void
+scm_c_hook_add (scm_t_c_hook *hook,
+ scm_t_c_hook_function func,
+ void *fn_data,
+ int appendp)
+{
+ scm_t_c_hook_entry *entry = scm_malloc (sizeof (scm_t_c_hook_entry));
+ scm_t_c_hook_entry **loc = &hook->first;
+ if (appendp)
+ while (*loc)
+ loc = &(*loc)->next;
+ entry->next = *loc;
+ entry->func = func;
+ entry->data = fn_data;
+ *loc = entry;
+}
+
+void
+scm_c_hook_remove (scm_t_c_hook *hook,
+ scm_t_c_hook_function func,
+ void *fn_data)
+{
+ scm_t_c_hook_entry **loc = &hook->first;
+ while (*loc)
+ {
+ if ((*loc)->func == func && (*loc)->data == fn_data)
+ {
+ scm_t_c_hook_entry *entry = *loc;
+ *loc = (*loc)->next;
+ free (entry);
+ return;
+ }
+ loc = &(*loc)->next;
+ }
+ fprintf (stderr, "Attempt to remove non-existent hook function\n");
+ abort ();
+}
+
+void *
+scm_c_hook_run (scm_t_c_hook *hook, void *data)
+{
+ scm_t_c_hook_entry *entry = hook->first;
+ scm_t_c_hook_type type = hook->type;
+ void *res = 0;
+ while (entry)
+ {
+ res = (entry->func) (hook->data, entry->data, data);
+ if (res)
+ {
+ if (type == SCM_C_HOOK_OR)
+ break;
+ }
+ else
+ {
+ if (type == SCM_C_HOOK_AND)
+ break;
+ }
+ entry = entry->next;
+ }
+ return res;
+}
+
+\f
+/* Scheme level hooks
+ *
+ * A hook is basically a list of procedures to be called at well defined
+ * points in time.
+ *
+ * Hook arity is not a full member of this type and therefore lacks an
+ * accessor. It exists to aid debugging and is not intended to be used in
+ * programs.
+ */
+
+scm_t_bits scm_tc16_hook;
+
+
+static int
+hook_print (SCM hook, SCM port, scm_print_state *pstate)
+{
+ SCM ls, name;
+ scm_puts ("#<hook ", port);
+ scm_intprint (SCM_HOOK_ARITY (hook), 10, port);
+ scm_putc (' ', port);
+ scm_uintprint (SCM_UNPACK (hook), 16, port);
+ ls = SCM_HOOK_PROCEDURES (hook);
+ while (SCM_NIMP (ls))
+ {
+ scm_putc (' ', port);
+ name = scm_procedure_name (SCM_CAR (ls));
+ if (scm_is_true (name))
+ scm_iprin1 (name, port, pstate);
+ else
+ scm_putc ('?', port);
+ ls = SCM_CDR (ls);
+ }
+ scm_putc ('>', port);
+ return 1;
+}
+
+
+SCM_DEFINE (scm_make_hook, "make-hook", 0, 1, 0,
+ (SCM n_args),
+ "Create a hook for storing procedure of arity @var{n_args}.\n"
+ "@var{n_args} defaults to zero. The returned value is a hook\n"
+ "object to be used with the other hook procedures.")
+#define FUNC_NAME s_scm_make_hook
+{
+ unsigned int n;
+
+ if (SCM_UNBNDP (n_args))
+ n = 0;
+ else
+ n = scm_to_unsigned_integer (n_args, 0, 16);
+
+ SCM_RETURN_NEWSMOB (scm_tc16_hook + (n << 16), SCM_UNPACK (SCM_EOL));
+}
+#undef FUNC_NAME
+
+
+SCM_DEFINE (scm_hook_p, "hook?", 1, 0, 0,
+ (SCM x),
+ "Return @code{#t} if @var{x} is a hook, @code{#f} otherwise.")
+#define FUNC_NAME s_scm_hook_p
+{
+ return scm_from_bool (SCM_HOOKP (x));
+}
+#undef FUNC_NAME
+
+
+SCM_DEFINE (scm_hook_empty_p, "hook-empty?", 1, 0, 0,
+ (SCM hook),
+ "Return @code{#t} if @var{hook} is an empty hook, @code{#f}\n"
+ "otherwise.")
+#define FUNC_NAME s_scm_hook_empty_p
+{
+ SCM_VALIDATE_HOOK (1, hook);
+ return scm_from_bool (scm_is_null (SCM_HOOK_PROCEDURES (hook)));
+}
+#undef FUNC_NAME
+
+
+SCM_DEFINE (scm_add_hook_x, "add-hook!", 2, 1, 0,
+ (SCM hook, SCM proc, SCM append_p),
+ "Add the procedure @var{proc} to the hook @var{hook}. The\n"
+ "procedure is added to the end if @var{append_p} is true,\n"
+ "otherwise it is added to the front. The return value of this\n"
+ "procedure is not specified.")
+#define FUNC_NAME s_scm_add_hook_x
+{
+ SCM arity, rest;
+ int n_args;
+ SCM_VALIDATE_HOOK (1, hook);
+ SCM_ASSERT (scm_is_true (arity = scm_i_procedure_arity (proc)),
+ proc, SCM_ARG2, FUNC_NAME);
+ n_args = SCM_HOOK_ARITY (hook);
+ if (scm_to_int (SCM_CAR (arity)) > n_args
+ || (scm_is_false (SCM_CADDR (arity))
+ && (scm_to_int (SCM_CAR (arity)) + scm_to_int (SCM_CADR (arity))
+ < n_args)))
+ scm_wrong_type_arg (FUNC_NAME, 2, proc);
+ rest = scm_delq_x (proc, SCM_HOOK_PROCEDURES (hook));
+ SCM_SET_HOOK_PROCEDURES (hook,
+ (!SCM_UNBNDP (append_p) && scm_is_true (append_p)
+ ? scm_append_x (scm_list_2 (rest, scm_list_1 (proc)))
+ : scm_cons (proc, rest)));
+ return SCM_UNSPECIFIED;
+}
+#undef FUNC_NAME
+
+
+SCM_DEFINE (scm_remove_hook_x, "remove-hook!", 2, 0, 0,
+ (SCM hook, SCM proc),
+ "Remove the procedure @var{proc} from the hook @var{hook}. The\n"
+ "return value of this procedure is not specified.")
+#define FUNC_NAME s_scm_remove_hook_x
+{
+ SCM_VALIDATE_HOOK (1, hook);
+ SCM_SET_HOOK_PROCEDURES (hook,
+ scm_delq_x (proc, SCM_HOOK_PROCEDURES (hook)));
+ return SCM_UNSPECIFIED;
+}
+#undef FUNC_NAME
+
+
+SCM_DEFINE (scm_reset_hook_x, "reset-hook!", 1, 0, 0,
+ (SCM hook),
+ "Remove all procedures from the hook @var{hook}. The return\n"
+ "value of this procedure is not specified.")
+#define FUNC_NAME s_scm_reset_hook_x
+{
+ SCM_VALIDATE_HOOK (1, hook);
+ SCM_SET_HOOK_PROCEDURES (hook, SCM_EOL);
+ return SCM_UNSPECIFIED;
+}
+#undef FUNC_NAME
+
+
+SCM_DEFINE (scm_run_hook, "run-hook", 1, 0, 1,
+ (SCM hook, SCM args),
+ "Apply all procedures from the hook @var{hook} to the arguments\n"
+ "@var{args}. The order of the procedure application is first to\n"
+ "last. The return value of this procedure is not specified.")
+#define FUNC_NAME s_scm_run_hook
+{
+ SCM_VALIDATE_HOOK (1, hook);
+ if (scm_ilength (args) != SCM_HOOK_ARITY (hook))
+ SCM_MISC_ERROR ("Hook ~S requires ~A arguments",
+ scm_list_2 (hook, scm_from_int (SCM_HOOK_ARITY (hook))));
+ scm_c_run_hook (hook, args);
+ return SCM_UNSPECIFIED;
+}
+#undef FUNC_NAME
+
+
+void
+scm_c_run_hook (SCM hook, SCM args)
+{
+ SCM procs = SCM_HOOK_PROCEDURES (hook);
+ while (SCM_NIMP (procs))
+ {
+ scm_apply_0 (SCM_CAR (procs), args);
+ procs = SCM_CDR (procs);
+ }
+}
+
+
+SCM_DEFINE (scm_hook_to_list, "hook->list", 1, 0, 0,
+ (SCM hook),
+ "Convert the procedure list of @var{hook} to a list.")
+#define FUNC_NAME s_scm_hook_to_list
+{
+ SCM_VALIDATE_HOOK (1, hook);
+ return scm_list_copy (SCM_HOOK_PROCEDURES (hook));
+}
+#undef FUNC_NAME
+
+
+\f
+
+void
+scm_init_hooks ()
+{
+ scm_tc16_hook = scm_make_smob_type ("hook", 0);
+ scm_set_smob_mark (scm_tc16_hook, scm_markcdr);
+ scm_set_smob_print (scm_tc16_hook, hook_print);
+#include "libguile/hooks.x"
+}
+
+/*
+ Local Variables:
+ c-file-style: "gnu"
+ End:
+*/
projects / lilypond.git / blobdiff