1 files changed, 85 insertions, 0 deletions
diff --git a/libc/arch-x86/bionic/__set_tls.c b/libc/arch-x86/bionic/__set_tls.c
new file mode 100755
index 0000000..8dff8d7
--- /dev/null
+++ b/libc/arch-x86/bionic/__set_tls.c
@@ -0,0 +1,85 @@
+/*
+ * Copyright (C) 2008 The Android Open Source Project
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *  * Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *  * Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+#include <pthread.h>
+
+struct user_desc {
+    unsigned int    entry_number;
+    unsigned long   base_addr;
+    unsigned int    limit;
+    unsigned int    seg_32bit:1;
+    unsigned int    contents:2;
+    unsigned int    read_exec_only:1;
+    unsigned int    limit_in_pages:1;
+    unsigned int    seg_not_present:1;
+    unsigned int    useable:1;
+    unsigned int    empty:25;
+};
+
+/* the following can't be const, since the first call will
+ * update the 'entry_number' field
+ */
+static struct user_desc  _tls_desc =
+{
+    -1,
+    0,
+    0x1000,
+    1,
+    0,
+    0,
+    1,
+    0,
+    1,
+    0
+};
+
+/* we implement thread local storage through the fs: segment descriptor
+ * we create a segment descriptor for the tls
+ */
+int __set_tls(void *ptr)
+{
+    int   rc, segment;
+
+    _tls_desc.base_addr = (unsigned long)ptr;
+
+    rc = __set_thread_area( &_tls_desc );
+    if (rc != 0)
+    {
+        /* could not set thread local area */
+        return -1;
+    }
+
+    /* this weird computation comes from GLibc */
+    segment = _tls_desc.entry_number*8 + 3;
+    asm __volatile__ (
+        "   movw %w0, %%fs" :: "r"(segment)
+    );
+    return 0;
+}
+
+
+