[PATCH] Fix random abort()

[Hristo Venev <hristo@xxxxxxxxxx>]

It is perfectly fine for the high nibble of the low 32 bits of a pointer
to be 6. Use NULL as a marker for missing entries.

Signed-off-by: Hristo Venev <hristo@xxxxxxxxxx>
---
 cachefilesd.c | 30 ++++++++++++------------------
 1 file changed, 12 insertions(+), 18 deletions(-)

diff --git a/cachefilesd.c b/cachefilesd.c
index d4d236f..851815d 100644
--- a/cachefilesd.c
+++ b/cachefilesd.c
@@ -30,6 +30,7 @@
 #define CACHEFILESD_VERSION "0.10.10"
 
 #define _GNU_SOURCE
+#include <assert.h>
 #include <stdarg.h>
 #include <stdbool.h>
 #include <stdio.h>
@@ -1092,7 +1093,6 @@ static void put_object(struct object *object)
 
 	parent = object->parent;
 
-	memset(object, 0x6d, sizeof(struct object));
 	free(object);
 
 	if (parent)
@@ -1213,7 +1213,7 @@ static void insert_into_cull_table(struct object *object)
 
 	/* newest object in table will be displaced by this one */
 	put_object(cullbuild[0]);
-	cullbuild[0] = (void *)(0x6b000000 | __LINE__);
+	cullbuild[0] = NULL;
 	object->usage++;
 
 	/* place directly in first slot if second is older */
@@ -1391,7 +1391,7 @@ next:
 
 			if (loop == nr_in_ready_table - 1) {
 				/* child was oldest object */
-				cullready[--nr_in_ready_table] = (void *)(0x6b000000 | __LINE__);
+				cullready[--nr_in_ready_table] = NULL;
 				put_object(child);
 				goto removed;
 			}
@@ -1400,7 +1400,7 @@ next:
 				memmove(&cullready[loop],
 					&cullready[loop + 1],
 					(nr_in_ready_table - (loop + 1)) * sizeof(cullready[0]));
-				cullready[--nr_in_ready_table] = (void *)(0x6b000000 | __LINE__);
+				cullready[--nr_in_ready_table] = NULL;
 				put_object(child);
 				goto removed;
 			}
@@ -1409,17 +1409,11 @@ next:
 				if (cullbuild[loop] == child)
 					break;
 
-			if (loop == nr_in_build_table - 1) {
-				/* child was oldest object */
-				cullbuild[--nr_in_build_table] = (void *)(0x6b000000 | __LINE__);
-				put_object(child);
-			}
-			else if (loop < nr_in_build_table - 1) {
-				/* child was somewhere in between */
+			if (loop < nr_in_build_table) {
 				memmove(&cullbuild[loop],
 					&cullbuild[loop + 1],
 					(nr_in_build_table - (loop + 1)) * sizeof(cullbuild[0]));
-				cullbuild[--nr_in_build_table] = (void *)(0x6b000000 | __LINE__);
+				cullbuild[--nr_in_build_table] = NULL;
 				put_object(child);
 			}
 
@@ -1531,7 +1525,7 @@ static void decant_cull_table(void)
 
 		n = copy * sizeof(cullready[0]);
 		memcpy(cullready, cullbuild, n);
-		memset(cullbuild, 0x6e, n);
+		memset(cullbuild, 0, n);
 		nr_in_ready_table = nr_in_build_table;
 		nr_in_build_table = 0;
 		goto check;
@@ -1558,8 +1552,9 @@ static void decant_cull_table(void)
 	memmove(&cullready[copy], &cullready[0], nr_in_ready_table * sizeof(cullready[0]));
 	nr_in_ready_table += copy;
 
-	memcpy(&cullready[0], &cullbuild[leave], copy * sizeof(cullready[0]));
-	memset(&cullbuild[leave], 0x6b, copy * sizeof(cullbuild[0]));
+	n = copy * sizeof(cullready[0]);
+	memcpy(&cullready[0], &cullbuild[leave], n);
+	memset(&cullbuild[leave], 0, n);
 	nr_in_build_table = leave;
 
 	if (copy + leave > culltable_size)
@@ -1567,8 +1562,7 @@ static void decant_cull_table(void)
 
 check:
 	for (loop = 0; loop < nr_in_ready_table; loop++)
-		if (((long)cullready[loop] & 0xf0000000) == 0x60000000)
-			abort();
+		assert(cullready[loop]);
 }
 
 /*****************************************************************************/
@@ -1645,6 +1639,6 @@ static void cull_objects(void)
 
 	if (cullready[nr_in_ready_table - 1]->cullable) {
 		cull_object(cullready[nr_in_ready_table - 1]);
-		cullready[--nr_in_ready_table] = (void *)(0x6b000000 | __LINE__);
+		cullready[--nr_in_ready_table] = NULL;
 	}
 }
-- 
2.43.0