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Get rid of undefined behavior that source and destination buffers ove…
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…rlap
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@nobu
nobu committed May 20, 2019
1 parent 8c8f2d9 commit e83f10b
Showing 1 changed file with 42 additions and 35 deletions.
77 changes: 42 additions & 35 deletions gc.c
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Expand Up @@ -11024,10 +11024,10 @@ method_type_name(rb_method_type_t type)
static void
rb_raw_iseq_info(char *buff, const int buff_size, const rb_iseq_t *iseq)
{
if (iseq->body && iseq->body->location.label && !RB_TYPE_P(iseq->body->location.pathobj, T_MOVED)) {
if (buff_size > 0 && iseq->body && iseq->body->location.label && !RB_TYPE_P(iseq->body->location.pathobj, T_MOVED)) {
VALUE path = rb_iseq_path(iseq);
VALUE n = iseq->body->location.first_lineno;
snprintf(buff, buff_size, "%s %s@%s:%d", buff,
snprintf(buff, buff_size, " %s@%s:%d",
RSTRING_PTR(iseq->body->location.label),
RSTRING_PTR(path),
n ? FIX2INT(n) : 0 );
Expand All @@ -11037,14 +11037,18 @@ rb_raw_iseq_info(char *buff, const int buff_size, const rb_iseq_t *iseq)
const char *
rb_raw_obj_info(char *buff, const int buff_size, VALUE obj)
{
int pos = 0;

#define BUFF_ARGS buff + pos, buff_size - pos
#define APPENDF(f) if ((pos += snprintf f) >= buff_size) goto end
if (SPECIAL_CONST_P(obj)) {
snprintf(buff, buff_size, "%s", obj_type_name(obj));
APPENDF((BUFF_ARGS, "%s", obj_type_name(obj)));

if (FIXNUM_P(obj)) {
snprintf(buff, buff_size, "%s %ld", buff, FIX2LONG(obj));
APPENDF((BUFF_ARGS, " %ld", FIX2LONG(obj)));
}
else if (SYMBOL_P(obj)) {
snprintf(buff, buff_size, "%s %s", buff, rb_id2name(SYM2ID(obj)));
APPENDF((BUFF_ARGS, " %s", rb_id2name(SYM2ID(obj))));
}
}
else {
Expand All @@ -11055,45 +11059,45 @@ rb_raw_obj_info(char *buff, const int buff_size, VALUE obj)
const int age = RVALUE_FLAGS_AGE(RBASIC(obj)->flags);

if (is_pointer_to_heap(&rb_objspace, (void *)obj)) {
snprintf(buff, buff_size, "%p [%d%s%s%s%s%s] %s",
APPENDF((BUFF_ARGS, "%p [%d%s%s%s%s%s] %s",
(void *)obj, age,
C(RVALUE_UNCOLLECTIBLE_BITMAP(obj), "L"),
C(RVALUE_MARK_BITMAP(obj), "M"),
C(RVALUE_PIN_BITMAP(obj), "P"),
C(RVALUE_MARKING_BITMAP(obj), "R"),
C(RVALUE_WB_UNPROTECTED_BITMAP(obj), "U"),
obj_type_name(obj));
obj_type_name(obj)));
}
else {
/* fake */
snprintf(buff, buff_size, "%p [%dXXXX] %s",
APPENDF((BUFF_ARGS, "%p [%dXXXX] %s",
(void *)obj, age,
obj_type_name(obj));
obj_type_name(obj)));
}
#else
snprintf(buff, buff_size, "%p [%s] %s",
APPENDF((BUFF_ARGS, "%p [%s] %s",
(void *)obj,
C(RVALUE_MARK_BITMAP(obj), "M"),
obj_type_name(obj));
obj_type_name(obj)));
#endif

if (internal_object_p(obj)) {
/* ignore */
}
else if (RBASIC(obj)->klass == 0) {
snprintf(buff, buff_size, "%s (temporary internal)", buff);
APPENDF((BUFF_ARGS, "(temporary internal)"));
}
else {
if (RTEST(RBASIC(obj)->klass)) {
VALUE class_path = rb_class_path_cached(RBASIC(obj)->klass);
if (!NIL_P(class_path)) {
snprintf(buff, buff_size, "%s (%s)", buff, RSTRING_PTR(class_path));
APPENDF((BUFF_ARGS, "(%s)", RSTRING_PTR(class_path)));
}
}
}

#if GC_DEBUG
snprintf(buff, buff_size, "%s @%s:%d", buff, RANY(obj)->file, RANY(obj)->line);
APPENDF((BUFF_ARGS, "@%s:%d", RANY(obj)->file, RANY(obj)->line));
#endif

switch (type) {
Expand All @@ -11102,54 +11106,54 @@ rb_raw_obj_info(char *buff, const int buff_size, VALUE obj)
break;
case T_ARRAY:
if (FL_TEST(obj, ELTS_SHARED)) {
snprintf(buff, buff_size, "%s shared -> %s", buff,
rb_obj_info(RARRAY(obj)->as.heap.aux.shared));
APPENDF((BUFF_ARGS, "shared -> %s",
rb_obj_info(RARRAY(obj)->as.heap.aux.shared)));
}
else if (FL_TEST(obj, RARRAY_EMBED_FLAG)) {
snprintf(buff, buff_size, "%s [%s%s] len: %d (embed)", buff,
APPENDF((BUFF_ARGS, "[%s%s] len: %d (embed)",
C(ARY_EMBED_P(obj), "E"),
C(ARY_SHARED_P(obj), "S"),
(int)RARRAY_LEN(obj));
(int)RARRAY_LEN(obj)));
}
else {
snprintf(buff, buff_size, "%s [%s%s%s] len: %d, capa:%d ptr:%p", buff,
APPENDF((BUFF_ARGS, "[%s%s%s] len: %d, capa:%d ptr:%p",
C(ARY_EMBED_P(obj), "E"),
C(ARY_SHARED_P(obj), "S"),
C(RARRAY_TRANSIENT_P(obj), "T"),
(int)RARRAY_LEN(obj),
ARY_EMBED_P(obj) ? -1 : (int)RARRAY(obj)->as.heap.aux.capa,
(void *)RARRAY_CONST_PTR_TRANSIENT(obj));
(void *)RARRAY_CONST_PTR_TRANSIENT(obj)));
}
break;
case T_STRING: {
snprintf(buff, buff_size, "%s %s", buff, RSTRING_PTR(obj));
APPENDF((BUFF_ARGS, "%s", RSTRING_PTR(obj)));
break;
}
case T_MOVED: {
snprintf(buff, buff_size, "-> %p", (void*)rb_gc_location(obj));
APPENDF((BUFF_ARGS, "-> %p", (void*)rb_gc_location(obj)));
break;
}
case T_HASH: {
snprintf(buff, buff_size, "%s [%c%c] %d", buff,
APPENDF((BUFF_ARGS, "[%c%c] %d",
RHASH_AR_TABLE_P(obj) ? 'A' : 'S',
RHASH_TRANSIENT_P(obj) ? 'T' : ' ',
(int)RHASH_SIZE(obj));
(int)RHASH_SIZE(obj)));
break;
}
case T_CLASS:
case T_MODULE:
{
VALUE class_path = rb_class_path_cached(obj);
if (!NIL_P(class_path)) {
snprintf(buff, buff_size, "%s %s", buff, RSTRING_PTR(class_path));
APPENDF((BUFF_ARGS, "%s", RSTRING_PTR(class_path)));
}
break;
}
case T_ICLASS:
{
VALUE class_path = rb_class_path_cached(RBASIC_CLASS(obj));
if (!NIL_P(class_path)) {
snprintf(buff, buff_size, "%s src:%s", buff, RSTRING_PTR(class_path));
APPENDF((BUFF_ARGS, "src:%s", RSTRING_PTR(class_path)));
}
break;
}
Expand All @@ -11158,11 +11162,11 @@ rb_raw_obj_info(char *buff, const int buff_size, VALUE obj)
uint32_t len = ROBJECT_NUMIV(obj);

if (RANY(obj)->as.basic.flags & ROBJECT_EMBED) {
snprintf(buff, buff_size, "%s (embed) len:%d", buff, len);
APPENDF((BUFF_ARGS, "(embed) len:%d", len));
}
else {
VALUE *ptr = ROBJECT_IVPTR(obj);
snprintf(buff, buff_size, "%s len:%d ptr:%p", buff, len, (void *)ptr);
APPENDF((BUFF_ARGS, "len:%d ptr:%p", len, (void *)ptr));
}
}
break;
Expand All @@ -11173,12 +11177,12 @@ rb_raw_obj_info(char *buff, const int buff_size, VALUE obj)
(block = vm_proc_block(obj)) != NULL &&
(vm_block_type(block) == block_type_iseq) &&
(iseq = vm_block_iseq(block)) != NULL) {
rb_raw_iseq_info(buff, buff_size, iseq);
rb_raw_iseq_info(BUFF_ARGS, iseq);
}
else {
const char * const type_name = rb_objspace_data_type_name(obj);
if (type_name) {
snprintf(buff, buff_size, "%s %s", buff, type_name);
APPENDF((BUFF_ARGS, "%s", type_name));
}
}
break;
Expand All @@ -11201,27 +11205,27 @@ rb_raw_obj_info(char *buff, const int buff_size, VALUE obj)
#undef IMEMO_NAME
default: UNREACHABLE;
}
snprintf(buff, buff_size, "%s %s", buff, imemo_name);
APPENDF((BUFF_ARGS, "%s", imemo_name));

switch (imemo_type(obj)) {
case imemo_ment: {
const rb_method_entry_t *me = &RANY(obj)->as.imemo.ment;
if (me->def) {
snprintf(buff, buff_size, "%s (called_id: %s, type: %s, alias: %d, owner: %s, defined_class: %s)", buff,
APPENDF((BUFF_ARGS, "(called_id: %s, type: %s, alias: %d, owner: %s, defined_class: %s)",
rb_id2name(me->called_id),
method_type_name(me->def->type),
me->def->alias_count,
obj_info(me->owner),
obj_info(me->defined_class));
obj_info(me->defined_class)));
}
else {
snprintf(buff, buff_size, "%s", rb_id2name(me->called_id));
APPENDF((BUFF_ARGS, "%s", rb_id2name(me->called_id)));
}
break;
}
case imemo_iseq: {
const rb_iseq_t *iseq = (const rb_iseq_t *)obj;
rb_raw_iseq_info(buff, buff_size, iseq);
rb_raw_iseq_info(BUFF_ARGS, iseq);
break;
}
default:
Expand All @@ -11234,7 +11238,10 @@ rb_raw_obj_info(char *buff, const int buff_size, VALUE obj)
#undef TF
#undef C
}
end:
return buff;
#undef APPENDF
#undef BUFF_ARGS
}

#if RGENGC_OBJ_INFO
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