aboutsummaryrefslogtreecommitdiff
path: root/shared/toxy/plusbob.c
diff options
context:
space:
mode:
Diffstat (limited to 'shared/toxy/plusbob.c')
-rw-r--r--shared/toxy/plusbob.c75
1 files changed, 51 insertions, 24 deletions
diff --git a/shared/toxy/plusbob.c b/shared/toxy/plusbob.c
index 9dae191..350b3c8 100644
--- a/shared/toxy/plusbob.c
+++ b/shared/toxy/plusbob.c
@@ -1,4 +1,4 @@
-/* Copyright (c) 2003 krzYszcz and others.
+/* Copyright (c) 2003-2005 krzYszcz and others.
* For information on usage and redistribution, and for a DISCLAIMER OF ALL
* WARRANTIES, see the file, "LICENSE.txt," in this distribution. */
@@ -11,12 +11,30 @@
//#define PLUSBOB_DEBUG
#endif
-/* LATER let there be a choice of using either fake-symbols, or gpointers.
+/* The main failure of the current implementation is when a foreign object
+ stores a faked symbol beyond lifetime of a wrappee. There is no obvious
+ way of protecting against stale pointers, other than leaking small
+ portions of memory (four words) with every new faked symbol. In case of
+ plustot, this is not a very big deal, since for each [+tot] object the
+ number of wrapped tcl objects is small and constant.
+
+ Another failure is when a foreign object binds something to a faked
+ symbol (for example, when a faked symbol is passed to an array's rename
+ method). This should not happen in usual contexts, and even if it does,
+ it will unlikely cause any real harm.
+
+ LATER let there be a choice of using either fake-symbols, or gpointers.
The gpointer layout would be such: gs_un points to a plusbob-like
- structure (without the bob_tag field), a unique integer code has to be
+ structure (without the bob_stub field), a unique integer code has to be
reserved for gs_which, the fields gp_un and gp_valid are ignored.
Using bob_refcount instead of gs_refcount is likely to simplify code. */
+typedef struct _plusstub
+{
+ t_symbol sb_tag; /* common value for all bob types */
+ t_plusbob *sb_bob;
+} t_plusstub;
+
/* Currently, objects of all +bob types are tagged with the same name: */
static char plustag_name[] = "+bob";
@@ -27,11 +45,11 @@ static void plustag_init(t_symbol *tag)
tag->s_next = 0;
}
-/* silent if caller is empty */
-int plustag_isvalid(t_symbol *tag, t_pd *caller)
+/* returns tagged +bob if valid, null otherwise (silent if caller is empty) */
+t_plusbob *plustag_isvalid(t_symbol *tag, t_pd *caller)
{
if (tag->s_name == plustag_name)
- return (1);
+ return (((t_plusstub *)tag)->sb_bob);
else if (caller)
{
if (strcmp(tag->s_name, plustag_name))
@@ -43,6 +61,14 @@ int plustag_isvalid(t_symbol *tag, t_pd *caller)
return (0);
}
+static t_plusstub *plusstub_create(t_plusbob *bob)
+{
+ t_plusstub *stub = getbytes(sizeof(*stub));
+ plustag_init(&stub->sb_tag);
+ stub->sb_bob = bob;
+ return (stub);
+}
+
/* +bob is an object tossed around, a bobbing object. Currently, this is
a wrapping for Tcl_Interp, Tcl_Obj, or a tcl variable, but the +bob
interface is abstract enough to be suitable for other types of objects.
@@ -128,7 +154,7 @@ t_plusbob *plusbob_create(t_plustype *tp, t_plusbob *parent)
}
if (bob = getbytes(tp->tp_size))
{
- plustag_init(&bob->bob_tag);
+ bob->bob_stub = (t_symbol *)plusstub_create(bob);
bob->bob_type = tp;
while (tp->tp_base) tp = tp->tp_base;
bob->bob_root = tp;
@@ -154,6 +180,7 @@ static void plusbob_free(t_plusbob *bob)
for (tp = bob->bob_type; tp; tp = tp->tp_base)
if (tp->tp_deletefn) (*tp->tp_deletefn)(bob);
freebytes(bob, (bob->bob_type ? bob->bob_type->tp_size : sizeof(*bob)));
+ /* the stub remains... */
}
void plusbob_preserve(t_plusbob *bob)
@@ -251,21 +278,21 @@ t_pd *plusbob_getowner(t_plusbob *bob)
void outlet_plusbob(t_outlet *o, t_plusbob *bob)
{
- outlet_symbol(o, (t_symbol *)bob);
+ outlet_symbol(o, bob->bob_stub);
}
-/* silent if caller is empty */
-int plustag_validtype(t_symbol *tag, t_symbol *tname, t_pd *caller)
+/* returns tagged +bob if valid, null otherwise (silent if caller is empty) */
+t_plusbob *plustag_validtype(t_symbol *tag, t_symbol *tname, t_pd *caller)
{
if (tag->s_name == plustag_name)
{
- if (((t_plusbob *)tag)->bob_type->tp_name == tname)
- return (1);
+ t_plusbob *bob = ((t_plusstub *)tag)->sb_bob;
+ if (bob->bob_type->tp_name == tname)
+ return (bob);
else if (caller)
{
- t_symbol *s = ((t_plusbob *)tag)->bob_type->tp_name;
- loud_error((caller == PLUSBOB_OWNER ?
- ((t_plusbob *)tag)->bob_owner : caller),
+ t_symbol *s = bob->bob_type->tp_name;
+ loud_error((caller == PLUSBOB_OWNER ? bob->bob_owner : caller),
"invalid type '%s' ('%s' expected)",
(s ? s->s_name : "<unknown>"),
(tname ? tname->s_name : "<unknown>"));
@@ -276,18 +303,18 @@ int plustag_validtype(t_symbol *tag, t_symbol *tname, t_pd *caller)
return (0);
}
-/* silent if caller is empty */
-int plustag_validroot(t_symbol *tag, t_symbol *rname, t_pd *caller)
+/* returns tagged +bob if valid, null otherwise (silent if caller is empty) */
+t_plusbob *plustag_validroot(t_symbol *tag, t_symbol *rname, t_pd *caller)
{
if (tag->s_name == plustag_name)
{
- if (((t_plusbob *)tag)->bob_root->tp_name == rname)
- return (1);
+ t_plusbob *bob = ((t_plusstub *)tag)->sb_bob;
+ if (bob->bob_root->tp_name == rname)
+ return (bob);
else if (caller)
{
- t_symbol *s = ((t_plusbob *)tag)->bob_root->tp_name;
- loud_error((caller == PLUSBOB_OWNER ?
- ((t_plusbob *)tag)->bob_owner : caller),
+ t_symbol *s = bob->bob_root->tp_name;
+ loud_error((caller == PLUSBOB_OWNER ? bob->bob_owner : caller),
"invalid base type '%s' ('%s' expected)",
(s ? s->s_name : "<unknown>"),
(rname ? rname->s_name : "<unknown>"));
@@ -301,7 +328,7 @@ int plustag_validroot(t_symbol *tag, t_symbol *rname, t_pd *caller)
t_symbol *plustag_typename(t_symbol *tag, int validate, t_pd *caller)
{
if (!validate || tag->s_name == plustag_name)
- return (((t_plusbob *)tag)->bob_type->tp_name);
+ return (((t_plusstub *)tag)->sb_bob->bob_type->tp_name);
else if (plustag_isvalid(tag, caller)) /* print the error there */
loudbug_bug("plustag_typename");
return (0);
@@ -310,7 +337,7 @@ t_symbol *plustag_typename(t_symbol *tag, int validate, t_pd *caller)
t_symbol *plustag_rootname(t_symbol *tag, int validate, t_pd *caller)
{
if (!validate || tag->s_name == plustag_name)
- return (((t_plusbob *)tag)->bob_root->tp_name);
+ return (((t_plusstub *)tag)->sb_bob->bob_root->tp_name);
else if (plustag_isvalid(tag, caller)) /* print the error there */
loudbug_bug("plustag_rootname");
return (0);
generated by cgit v1.2.1 (git 2.18.0) at 2024-12-24 17:14:28 +0000