[threads] Add function to stringify thread state names.

[mono.git] / mono / utils / mach-support-x86.c

diff --git a/mono/utils/mach-support-x86.c b/mono/utils/mach-support-x86.c
index e65fe6bdeefe05a40f603c9d482fedbb2baa8b04..5650e8b92c916b7a584ccfe073d9e915a30ff489 100644 (file)
--- a/mono/utils/mach-support-x86.c
+++ b/mono/utils/mach-support-x86.c
@@ -16,6 +16,22 @@
 #include "utils/mono-sigcontext.h"
 #include "mach-support.h"
 
+/* Known offsets used for TLS storage*/
+
+/* All OSX versions up to 10.8 */
+#define TLS_VECTOR_OFFSET_CATS 0x48
+#define TLS_VECTOR_OFFSET_10_9 0xb0
+#define TLS_VECTOR_OFFSET_10_11 0x100
+
+
+/* This is 2 slots less than the known low */
+#define TLS_PROBE_LOW_WATERMARK 0x40
+/* This is 28 slots above the know high, which is more than the known high-low*/
+#define TLS_PROBE_HIGH_WATERMARK 0x120
+
+
+static int tls_vector_offset;
+
 void *
 mono_mach_arch_get_ip (thread_state_t state)
 {
@@ -65,31 +81,39 @@ mono_mach_arch_get_thread_state_size ()
 kern_return_t
 mono_mach_arch_get_thread_state (thread_port_t thread, thread_state_t state, mach_msg_type_number_t *count)
 {
+#if defined(HOST_WATCHOS)
+       g_error ("thread_get_state() is not supported by this platform");
+#else
        x86_thread_state32_t *arch_state = (x86_thread_state32_t *) state;
        kern_return_t ret;
 
        *count = x86_THREAD_STATE32_COUNT;
-
        ret = thread_get_state (thread, x86_THREAD_STATE32, (thread_state_t) arch_state, count);
 
        return ret;
+#endif
 }
 
 kern_return_t
 mono_mach_arch_set_thread_state (thread_port_t thread, thread_state_t state, mach_msg_type_number_t count)
 {
+#if defined(HOST_WATCHOS)
+       g_error ("thread_set_state() is not supported by this platform");
+#else
        return thread_set_state (thread, x86_THREAD_STATE32, state, count);
+#endif 
 }
 
 void *
 mono_mach_get_tls_address_from_thread (pthread_t thread, pthread_key_t key)
 {
        /* OSX stores TLS values in a hidden array inside the pthread_t structure
-        * They are keyed off a giant array offset 0x48 into the pointer.  This value
+        * They are keyed off a giant array from a known offset into the pointer.  This value
         * is baked into their pthread_getspecific implementation
         */
        intptr_t *p = (intptr_t *) thread;
-       intptr_t **tsd = (intptr_t **) ((char*)p + 0x48);
+       intptr_t **tsd = (intptr_t **) ((char*)p + tls_vector_offset);
+       g_assert (tls_vector_offset != -1);
 
        return (void *) &tsd [key];     
 }
@@ -100,5 +124,44 @@ mono_mach_arch_get_tls_value_from_thread (pthread_t thread, guint32 key)
        return *(void**)mono_mach_get_tls_address_from_thread (thread, key);
 }
 
+void
+mono_mach_init (pthread_key_t key)
+{
+       int i;
+       void *old_value = pthread_getspecific (key);
+       void *canary = (void*)0xDEADBEEFu;
+
+       pthread_key_create (&key, NULL);
+       g_assert (old_value != canary);
+
+       pthread_setspecific (key, canary);
+
+       /*First we probe for cats*/
+       tls_vector_offset = TLS_VECTOR_OFFSET_CATS;
+       if (mono_mach_arch_get_tls_value_from_thread (pthread_self (), key) == canary)
+               goto ok;
+
+       tls_vector_offset = TLS_VECTOR_OFFSET_10_9;
+       if (mono_mach_arch_get_tls_value_from_thread (pthread_self (), key) == canary)
+               goto ok;
+
+       tls_vector_offset = TLS_VECTOR_OFFSET_10_11;
+       if (mono_mach_arch_get_tls_value_from_thread (pthread_self (), key) == canary)
+               goto ok;
+
+       /*Fallback to scanning a large range of offsets*/
+       for (i = TLS_PROBE_LOW_WATERMARK; i <= TLS_PROBE_HIGH_WATERMARK; i += 4) {
+               tls_vector_offset = i;
+               if (mono_mach_arch_get_tls_value_from_thread (pthread_self (), key) == canary) {
+                       g_warning ("Found new TLS offset at %d", i);
+                       goto ok;
+               }
+       }
+
+       tls_vector_offset = -1;
+       g_warning ("could not discover the mach TLS offset");
+ok:
+       pthread_setspecific (key, old_value);
+}
 
 #endif