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changeset 5891:aa673ac29a70 draft

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(svn r8508) -Codechange (r5762): [win32] Use an atomic operation to query and set the value of _global_dir_is_in_use for opendir etc to guarantee concurrency.
author Darkvater <Darkvater@openttd.org>
date Thu, 01 Feb 2007 13:01:05 +0000
parents 20ba2da91f50
children 64960d9ae9f3
files src/win32.cpp
diffstat 1 files changed, 4 insertions(+), 5 deletions(-) [+]
line wrap: on
line diff
--- a/src/win32.cpp
+++ b/src/win32.cpp
@@ -625,20 +625,19 @@
 
 /* suballocator - satisfies most requests with a reusable static instance.
  * this avoids hundreds of alloc/free which would fragment the heap.
- * To guarantee reentrancy, we fall back to malloc if the instance is
+ * To guarantee concurrency, we fall back to malloc if the instance is
  * already in use (it's important to avoid suprises since this is such a
  * low-level routine). */
 static DIR _global_dir;
-static bool _global_dir_is_in_use = false;
+static LONG _global_dir_is_in_use = false;
 
 static inline DIR *dir_calloc(void)
 {
 	DIR *d;
 
-	if (_global_dir_is_in_use) {
+	if (InterlockedExchange(&_global_dir_is_in_use, true) == (LONG)true) {
 		d = CallocT<DIR>(1);
 	} else {
-		_global_dir_is_in_use = true;
 		d = &_global_dir;
 		memset(d, 0, sizeof(*d));
 	}
@@ -648,7 +647,7 @@
 static inline void dir_free(DIR *d)
 {
 	if (d == &_global_dir) {
-		_global_dir_is_in_use = false;
+		_global_dir_is_in_use = (LONG)false;
 	} else {
 		free(d);
 	}