+
+
+/**
+ * Put a tag (arbitrary integer) on a memory block.
+ * Can be useful for debugging.
+ */
+void
+debug_memory_tag(void *ptr, unsigned tag)
+{
+ struct debug_memory_header *hdr;
+
+ if (!ptr)
+ return;
+
+ hdr = header_from_data(ptr);
+ if (hdr->magic != DEBUG_MEMORY_MAGIC) {
+ debug_printf("%s corrupted memory at %p\n", __FUNCTION__, ptr);
+ debug_assert(0);
+ }
+
+ hdr->tag = tag;
+}
+
+
+/**
+ * Check the given block of memory for validity/corruption.
+ */
+void
+debug_memory_check_block(void *ptr)
+{
+ struct debug_memory_header *hdr;
+ struct debug_memory_footer *ftr;
+
+ if (!ptr)
+ return;
+
+ hdr = header_from_data(ptr);
+ ftr = footer_from_header(hdr);
+
+ if (hdr->magic != DEBUG_MEMORY_MAGIC) {
+ debug_printf("%s:%u:%s: bad or corrupted memory %p\n",
+ hdr->file, hdr->line, hdr->function, ptr);
+ debug_assert(0);
+ }
+
+ if (ftr->magic != DEBUG_MEMORY_MAGIC) {
+ debug_printf("%s:%u:%s: buffer overflow %p\n",
+ hdr->file, hdr->line, hdr->function, ptr);
+ debug_assert(0);
+ }
+}
+
+
+
+/**
+ * We can periodically call this from elsewhere to do a basic sanity
+ * check of the heap memory we've allocated.
+ */
+void
+debug_memory_check(void)
+{
+ struct list_head *entry;
+
+ entry = list.prev;
+ for (; entry != &list; entry = entry->prev) {
+ struct debug_memory_header *hdr;
+ struct debug_memory_footer *ftr;
+ const char *ptr;
+
+ hdr = LIST_ENTRY(struct debug_memory_header, entry, head);
+ ftr = footer_from_header(hdr);
+ ptr = (const char *) data_from_header(hdr);
+
+ if (hdr->magic != DEBUG_MEMORY_MAGIC) {
+ debug_printf("%s:%u:%s: bad or corrupted memory %p\n",
+ hdr->file, hdr->line, hdr->function, ptr);
+ debug_assert(0);
+ }
+
+ if (ftr->magic != DEBUG_MEMORY_MAGIC) {
+ debug_printf("%s:%u:%s: buffer overflow %p\n",
+ hdr->file, hdr->line, hdr->function, ptr);
+ debug_assert(0);
+ }
+
+#if DEBUG_FREED_MEMORY
+ /* If this block is marked as freed, check that it hasn't been touched */
+ if (hdr->freed) {
+ int i;
+ for (i = 0; i < hdr->size; i++) {
+ if (ptr[i] != DEBUG_FREED_BYTE) {
+ debug_printf("Memory error: byte %d of block at %p of size %d is 0x%x\n",
+ i, ptr, hdr->size, ptr[i]);
+ debug_printf("Block was freed at %s:%d\n", hdr->file, hdr->line);
+ }
+ assert(ptr[i] == DEBUG_FREED_BYTE);
+ }
+ }
+#endif
+ }
+}