svn commit: samba r15824 - in branches/SAMBA_4_0/source/lib/talloc:
.
tridge at samba.org
tridge at samba.org
Tue May 23 03:51:46 GMT 2006
Author: tridge
Date: 2006-05-23 03:51:44 +0000 (Tue, 23 May 2006)
New Revision: 15824
WebSVN: http://websvn.samba.org/cgi-bin/viewcvs.cgi?view=rev&root=samba&rev=15824
Log:
fixed a subtle talloc bug to do with memory context loops. When you
have a structure that references one of its parents, and a parent of
that parent is freed, then the whole structure should be freed, not
just the reference.
this was found by the change notify code, as a side effect of fixing
the memory leak yesterday
Modified:
branches/SAMBA_4_0/source/lib/talloc/talloc.c
branches/SAMBA_4_0/source/lib/talloc/talloc.h
branches/SAMBA_4_0/source/lib/talloc/testsuite.c
Changeset:
Modified: branches/SAMBA_4_0/source/lib/talloc/talloc.c
===================================================================
--- branches/SAMBA_4_0/source/lib/talloc/talloc.c 2006-05-22 23:48:09 UTC (rev 15823)
+++ branches/SAMBA_4_0/source/lib/talloc/talloc.c 2006-05-23 03:51:44 UTC (rev 15824)
@@ -542,7 +542,13 @@
tc = talloc_chunk_from_ptr(ptr);
if (tc->refs) {
+ int is_child;
+ struct talloc_reference_handle *handle = tc->refs;
+ is_child = talloc_is_parent(handle, handle->ptr);
talloc_reference_destructor(tc->refs);
+ if (is_child) {
+ return talloc_free(ptr);
+ }
return -1;
}
@@ -1197,7 +1203,9 @@
return TC_PTR_FROM_CHUNK(tc);
}
while (tc && tc->prev) tc = tc->prev;
- tc = tc->parent;
+ if (tc) {
+ tc = tc->parent;
+ }
}
return NULL;
}
@@ -1219,6 +1227,30 @@
while (tc) {
fprintf(file, "\t'%s'\n", talloc_get_name(TC_PTR_FROM_CHUNK(tc)));
while (tc && tc->prev) tc = tc->prev;
- tc = tc->parent;
+ if (tc) {
+ tc = tc->parent;
+ }
}
}
+
+/*
+ return 1 if ptr is a parent of context
+*/
+int talloc_is_parent(const void *context, const char *ptr)
+{
+ struct talloc_chunk *tc;
+
+ if (context == NULL) {
+ return 0;
+ }
+
+ tc = talloc_chunk_from_ptr(context);
+ while (tc) {
+ if (TC_PTR_FROM_CHUNK(tc) == ptr) return 1;
+ while (tc && tc->prev) tc = tc->prev;
+ if (tc) {
+ tc = tc->parent;
+ }
+ }
+ return 0;
+}
Modified: branches/SAMBA_4_0/source/lib/talloc/talloc.h
===================================================================
--- branches/SAMBA_4_0/source/lib/talloc/talloc.h 2006-05-22 23:48:09 UTC (rev 15823)
+++ branches/SAMBA_4_0/source/lib/talloc/talloc.h 2006-05-23 03:51:44 UTC (rev 15824)
@@ -137,6 +137,7 @@
size_t talloc_get_size(const void *ctx);
void *talloc_find_parent_byname(const void *ctx, const char *name);
void talloc_show_parents(const void *context, FILE *file);
+int talloc_is_parent(const void *context, const char *ptr);
#endif
Modified: branches/SAMBA_4_0/source/lib/talloc/testsuite.c
===================================================================
--- branches/SAMBA_4_0/source/lib/talloc/testsuite.c 2006-05-22 23:48:09 UTC (rev 15823)
+++ branches/SAMBA_4_0/source/lib/talloc/testsuite.c 2006-05-23 03:51:44 UTC (rev 15824)
@@ -824,7 +824,7 @@
}
-BOOL test_lifeless(void)
+static BOOL test_lifeless(void)
{
char *top = talloc_new(NULL);
char *parent, *child;
@@ -836,14 +836,57 @@
child = talloc_strdup(parent, "child");
talloc_reference(child, parent);
talloc_reference(child_owner, child);
+ talloc_report_full(top, stdout);
talloc_unlink(top, parent);
talloc_free(child);
talloc_report_full(top, stdout);
talloc_free(top);
+ talloc_free(child_owner);
+#if 0
+ talloc_free(child);
+#endif
return True;
}
+static int loop_destructor_count;
+static int test_loop_destructor(void *ptr)
+{
+ printf("loop destructor\n");
+ loop_destructor_count++;
+ return 0;
+}
+
+static BOOL test_loop(void)
+{
+ char *top = talloc_new(NULL);
+ char *parent;
+ struct req1 {
+ char *req2, *req3;
+ } *req1;
+
+ printf("TESTING TALLOC LOOP DESTRUCTION\n");
+ parent = talloc_strdup(top, "parent");
+ req1 = talloc(parent, struct req1);
+ req1->req2 = talloc_strdup(req1, "req2");
+ talloc_set_destructor(req1->req2, test_loop_destructor);
+ req1->req3 = talloc_strdup(req1, "req3");
+ talloc_reference(req1->req3, req1);
+ talloc_report_full(top, stdout);
+ talloc_free(parent);
+ talloc_report_full(top, stdout);
+ talloc_report_full(NULL, stdout);
+ talloc_free(top);
+
+ if (loop_destructor_count != 1) {
+ printf("FAILED TO FIRE LOOP DESTRUCTOR\n");
+ return False;
+ }
+
+ return True;
+}
+
+
BOOL torture_local_talloc(struct torture_context *torture)
{
BOOL ret = True;
@@ -861,6 +904,7 @@
ret &= test_realloc_fn();
ret &= test_type();
ret &= test_lifeless();
+ ret &= test_loop();
if (ret) {
ret &= test_speed();
}
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