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Diffstat (limited to 'vendor/github.com/coreos/pkg/dlopen/dlopen.go')
-rw-r--r--vendor/github.com/coreos/pkg/dlopen/dlopen.go82
1 files changed, 82 insertions, 0 deletions
diff --git a/vendor/github.com/coreos/pkg/dlopen/dlopen.go b/vendor/github.com/coreos/pkg/dlopen/dlopen.go
new file mode 100644
index 000000000..23774f612
--- /dev/null
+++ b/vendor/github.com/coreos/pkg/dlopen/dlopen.go
@@ -0,0 +1,82 @@
+// Copyright 2016 CoreOS, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package dlopen provides some convenience functions to dlopen a library and
+// get its symbols.
+package dlopen
+
+// #cgo LDFLAGS: -ldl
+// #include <stdlib.h>
+// #include <dlfcn.h>
+import "C"
+import (
+ "errors"
+ "fmt"
+ "unsafe"
+)
+
+var ErrSoNotFound = errors.New("unable to open a handle to the library")
+
+// LibHandle represents an open handle to a library (.so)
+type LibHandle struct {
+ Handle unsafe.Pointer
+ Libname string
+}
+
+// GetHandle tries to get a handle to a library (.so), attempting to access it
+// by the names specified in libs and returning the first that is successfully
+// opened. Callers are responsible for closing the handler. If no library can
+// be successfully opened, an error is returned.
+func GetHandle(libs []string) (*LibHandle, error) {
+ for _, name := range libs {
+ libname := C.CString(name)
+ defer C.free(unsafe.Pointer(libname))
+ handle := C.dlopen(libname, C.RTLD_LAZY)
+ if handle != nil {
+ h := &LibHandle{
+ Handle: handle,
+ Libname: name,
+ }
+ return h, nil
+ }
+ }
+ return nil, ErrSoNotFound
+}
+
+// GetSymbolPointer takes a symbol name and returns a pointer to the symbol.
+func (l *LibHandle) GetSymbolPointer(symbol string) (unsafe.Pointer, error) {
+ sym := C.CString(symbol)
+ defer C.free(unsafe.Pointer(sym))
+
+ C.dlerror()
+ p := C.dlsym(l.Handle, sym)
+ e := C.dlerror()
+ if e != nil {
+ return nil, fmt.Errorf("error resolving symbol %q: %v", symbol, errors.New(C.GoString(e)))
+ }
+
+ return p, nil
+}
+
+// Close closes a LibHandle.
+func (l *LibHandle) Close() error {
+ C.dlerror()
+ C.dlclose(l.Handle)
+ e := C.dlerror()
+ if e != nil {
+ return fmt.Errorf("error closing %v: %v", l.Libname, errors.New(C.GoString(e)))
+ }
+
+ return nil
+}