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authorRuss Cox <rsc@golang.org>2014-12-05 11:43:41 -0500
committerRuss Cox <rsc@golang.org>2014-12-05 11:43:41 -0500
commit8670c52abcdb260f5366d6fa205a7c7f9b5b1067 (patch)
tree3781a05c976360f88b736c71316dadc789e02062 /src/runtime/cgo/callbacks.go
parent3ebebda3a7495402239db4369d59d73749c1bfa2 (diff)
parent6d3ba1914e289ed223f7bb69f34604c0e2ae5384 (diff)
downloadgo-8670c52abcdb260f5366d6fa205a7c7f9b5b1067.tar.gz
all: merge dev.cc (81884b89bd88) into default
With this change, default now contains Go 1.5 work. Any future bug fixes for Go 1.4 in the compilers or the runtime will have to be made directly to the release branch.
Diffstat (limited to 'src/runtime/cgo/callbacks.go')
-rw-r--r--src/runtime/cgo/callbacks.go95
1 files changed, 95 insertions, 0 deletions
diff --git a/src/runtime/cgo/callbacks.go b/src/runtime/cgo/callbacks.go
new file mode 100644
index 000000000..1e8b59054
--- /dev/null
+++ b/src/runtime/cgo/callbacks.go
@@ -0,0 +1,95 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package cgo
+
+import "unsafe"
+
+// These utility functions are available to be called from code
+// compiled with gcc via crosscall2.
+
+// cgocallback is defined in runtime
+//go:linkname _runtime_cgocallback runtime.cgocallback
+func _runtime_cgocallback(unsafe.Pointer, unsafe.Pointer, uintptr)
+
+// The declaration of crosscall2 is:
+// void crosscall2(void (*fn)(void *, int), void *, int);
+//
+// We need to export the symbol crosscall2 in order to support
+// callbacks from shared libraries. This applies regardless of
+// linking mode.
+//go:cgo_export_static crosscall2
+//go:cgo_export_dynamic crosscall2
+
+// Allocate memory. This allocates the requested number of bytes in
+// memory controlled by the Go runtime. The allocated memory will be
+// zeroed. You are responsible for ensuring that the Go garbage
+// collector can see a pointer to the allocated memory for as long as
+// it is valid, e.g., by storing a pointer in a local variable in your
+// C function, or in memory allocated by the Go runtime. If the only
+// pointers are in a C global variable or in memory allocated via
+// malloc, then the Go garbage collector may collect the memory.
+
+// Call like this in code compiled with gcc:
+// struct { size_t len; void *ret; } a;
+// a.len = /* number of bytes to allocate */;
+// crosscall2(_cgo_allocate, &a, sizeof a);
+// /* Here a.ret is a pointer to the allocated memory. */
+
+//go:linkname _runtime_cgo_allocate_internal runtime._cgo_allocate_internal
+var _runtime_cgo_allocate_internal byte
+
+//go:linkname _cgo_allocate _cgo_allocate
+//go:cgo_export_static _cgo_allocate
+//go:cgo_export_dynamic _cgo_allocate
+//go:nosplit
+func _cgo_allocate(a unsafe.Pointer, n int32) {
+ _runtime_cgocallback(unsafe.Pointer(&_runtime_cgo_allocate_internal), a, uintptr(n))
+}
+
+// Panic. The argument is converted into a Go string.
+
+// Call like this in code compiled with gcc:
+// struct { const char *p; } a;
+// a.p = /* string to pass to panic */;
+// crosscall2(_cgo_panic, &a, sizeof a);
+// /* The function call will not return. */
+
+//go:linkname _runtime_cgo_panic_internal runtime._cgo_panic_internal
+var _runtime_cgo_panic_internal byte
+
+//go:linkname _cgo_panic _cgo_panic
+//go:cgo_export_static _cgo_panic
+//go:cgo_export_dynamic _cgo_panic
+//go:nosplit
+func _cgo_panic(a unsafe.Pointer, n int32) {
+ _runtime_cgocallback(unsafe.Pointer(&_runtime_cgo_panic_internal), a, uintptr(n))
+}
+
+//go:cgo_import_static x_cgo_init
+//go:linkname x_cgo_init x_cgo_init
+//go:linkname _cgo_init _cgo_init
+var x_cgo_init byte
+var _cgo_init = &x_cgo_init
+
+//go:cgo_import_static x_cgo_malloc
+//go:linkname x_cgo_malloc x_cgo_malloc
+//go:linkname _cgo_malloc _cgo_malloc
+var x_cgo_malloc byte
+var _cgo_malloc = &x_cgo_malloc
+
+//go:cgo_import_static x_cgo_free
+//go:linkname x_cgo_free x_cgo_free
+//go:linkname _cgo_free _cgo_free
+var x_cgo_free byte
+var _cgo_free = &x_cgo_free
+
+//go:cgo_import_static x_cgo_thread_start
+//go:linkname x_cgo_thread_start x_cgo_thread_start
+//go:linkname _cgo_thread_start _cgo_thread_start
+var x_cgo_thread_start byte
+var _cgo_thread_start = &x_cgo_thread_start
+
+//go:cgo_export_static _cgo_topofstack
+//go:cgo_export_dynamic _cgo_topofstack