1 files changed, 99 insertions, 0 deletions
diff --git a/vendor/github.com/ebitengine/purego/dlfcn.go b/vendor/github.com/ebitengine/purego/dlfcn.go
new file mode 100644
index 0000000..f70a245
--- /dev/null
+++ b/vendor/github.com/ebitengine/purego/dlfcn.go
@@ -0,0 +1,99 @@
+// SPDX-License-Identifier: Apache-2.0
+// SPDX-FileCopyrightText: 2022 The Ebitengine Authors
+
+//go:build (darwin || freebsd || linux) && !android && !faketime
+
+package purego
+
+import (
+	"unsafe"
+)
+
+// Unix Specification for dlfcn.h: https://pubs.opengroup.org/onlinepubs/7908799/xsh/dlfcn.h.html
+
+var (
+	fnDlopen  func(path string, mode int) uintptr
+	fnDlsym   func(handle uintptr, name string) uintptr
+	fnDlerror func() string
+	fnDlclose func(handle uintptr) bool
+)
+
+func init() {
+	RegisterFunc(&fnDlopen, dlopenABI0)
+	RegisterFunc(&fnDlsym, dlsymABI0)
+	RegisterFunc(&fnDlerror, dlerrorABI0)
+	RegisterFunc(&fnDlclose, dlcloseABI0)
+}
+
+// Dlopen examines the dynamic library or bundle file specified by path. If the file is compatible
+// with the current process and has not already been loaded into the
+// current process, it is loaded and linked. After being linked, if it contains
+// any initializer functions, they are called, before Dlopen
+// returns. It returns a handle that can be used with Dlsym and Dlclose.
+// A second call to Dlopen with the same path will return the same handle, but the internal
+// reference count for the handle will be incremented. Therefore, all
+// Dlopen calls should be balanced with a Dlclose call.
+//
+// This function is not available on Windows.
+// Use [golang.org/x/sys/windows.LoadLibrary], [golang.org/x/sys/windows.LoadLibraryEx],
+// [golang.org/x/sys/windows.NewLazyDLL], or [golang.org/x/sys/windows.NewLazySystemDLL] for Windows instead.
+func Dlopen(path string, mode int) (uintptr, error) {
+	u := fnDlopen(path, mode)
+	if u == 0 {
+		return 0, Dlerror{fnDlerror()}
+	}
+	return u, nil
+}
+
+// Dlsym takes a "handle" of a dynamic library returned by Dlopen and the symbol name.
+// It returns the address where that symbol is loaded into memory. If the symbol is not found,
+// in the specified library or any of the libraries that were automatically loaded by Dlopen
+// when that library was loaded, Dlsym returns zero.
+//
+// This function is not available on Windows.
+// Use [golang.org/x/sys/windows.GetProcAddress] for Windows instead.
+func Dlsym(handle uintptr, name string) (uintptr, error) {
+	u := fnDlsym(handle, name)
+	if u == 0 {
+		return 0, Dlerror{fnDlerror()}
+	}
+	return u, nil
+}
+
+// Dlclose decrements the reference count on the dynamic library handle.
+// If the reference count drops to zero and no other loaded libraries
+// use symbols in it, then the dynamic library is unloaded.
+//
+// This function is not available on Windows.
+// Use [golang.org/x/sys/windows.FreeLibrary] for Windows instead.
+func Dlclose(handle uintptr) error {
+	if fnDlclose(handle) {
+		return Dlerror{fnDlerror()}
+	}
+	return nil
+}
+
+func loadSymbol(handle uintptr, name string) (uintptr, error) {
+	return Dlsym(handle, name)
+}
+
+// these functions exist in dlfcn_stubs.s and are calling C functions linked to in dlfcn_GOOS.go
+// the indirection is necessary because a function is actually a pointer to the pointer to the code.
+// sadly, I do not know of anyway to remove the assembly stubs entirely because //go:linkname doesn't
+// appear to work if you link directly to the C function on darwin arm64.
+
+//go:linkname dlopen dlopen
+var dlopen uintptr
+var dlopenABI0 = uintptr(unsafe.Pointer(&dlopen))
+
+//go:linkname dlsym dlsym
+var dlsym uintptr
+var dlsymABI0 = uintptr(unsafe.Pointer(&dlsym))
+
+//go:linkname dlclose dlclose
+var dlclose uintptr
+var dlcloseABI0 = uintptr(unsafe.Pointer(&dlclose))
+
+//go:linkname dlerror dlerror
+var dlerror uintptr
+var dlerrorABI0 = uintptr(unsafe.Pointer(&dlerror))