X-Git-Url: http://nsz.repo.hu/git/?a=blobdiff_plain;f=src%2Fthread%2F__unmapself.c;h=1d3bee1d9b0404494db6d2745e31ebe780ed682e;hb=c30cbcb0a646b1f13a22c645616dce624465b883;hp=e69de29bb2d1d6434b8b29ae775ad8c2e48c5391;hpb=276904c2f6bde3a31a24ebfa201482601d18b4f9;p=musl

diff --git a/src/thread/__unmapself.c b/src/thread/__unmapself.c
index e69de29b..1d3bee1d 100644
--- a/src/thread/__unmapself.c
+++ b/src/thread/__unmapself.c
@@ -0,0 +1,29 @@
+#include "pthread_impl.h"
+#include "atomic.h"
+#include "syscall.h"
+/* cheat and reuse CRTJMP macro from dynlink code */
+#include "dynlink.h"
+
+static volatile int lock;
+static void *unmap_base;
+static size_t unmap_size;
+static char shared_stack[256];
+
+static void do_unmap()
+{
+	__syscall(SYS_munmap, unmap_base, unmap_size);
+	__syscall(SYS_exit);
+}
+
+void __unmapself(void *base, size_t size)
+{
+	int tid=__pthread_self()->tid;
+	char *stack = shared_stack + sizeof shared_stack;
+	stack -= (uintptr_t)stack % 16;
+	while (lock || a_cas(&lock, 0, tid))
+		a_spin();
+	__syscall(SYS_set_tid_address, &lock);
+	unmap_base = base;
+	unmap_size = size;
+	CRTJMP(do_unmap, stack);
+}