internal/nvsandboxutils: Look up entry points with dlsym

internal/nvsandboxutils/cgo_helpers.h

@@ -18,6 +18,7 @@
 // Code generated by https://git.io/c-for-go. DO NOT EDIT.
 
 #include "nvsandboxutils.h"
+#include "dlsym_static.h"
 #include <stdlib.h>
 #pragma once
 

internal/nvsandboxutils/dlsym_static.c

@@ -0,0 +1,70 @@
+/**
+# Copyright 2026 NVIDIA CORPORATION
+#
+# 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.
+**/
+
+#include <dlfcn.h>
+#include <stddef.h>
+
+#include "dlsym_static.h"
+
+nvSandboxUtilsRet_t nvSandboxUtilsInit_dl(nvSandboxUtilsInitInput_t *input)
+{
+    nvSandboxUtilsRet_t (*fn)(nvSandboxUtilsInitInput_t *) = dlsym(RTLD_DEFAULT, "nvSandboxUtilsInit");
+    if (fn == NULL) {
+        return NVSANDBOXUTILS_ERROR_LIBRARY_LOAD;
+    }
+
+    return fn(input);
+}
+
+nvSandboxUtilsRet_t nvSandboxUtilsShutdown_dl(void)
+{
+    nvSandboxUtilsRet_t (*fn)(void) = dlsym(RTLD_DEFAULT, "nvSandboxUtilsShutdown");
+    if (fn == NULL) {
+        return NVSANDBOXUTILS_ERROR_LIBRARY_LOAD;
+    }
+
+    return fn();
+}
+
+nvSandboxUtilsRet_t nvSandboxUtilsGetDriverVersion_dl(char *version, unsigned int length)
+{
+    nvSandboxUtilsRet_t (*fn)(char *, unsigned int) = dlsym(RTLD_DEFAULT, "nvSandboxUtilsGetDriverVersion");
+    if (fn == NULL) {
+        return NVSANDBOXUTILS_ERROR_LIBRARY_LOAD;
+    }
+
+    return fn(version, length);
+}
+
+nvSandboxUtilsRet_t nvSandboxUtilsGetGpuResource_dl(nvSandboxUtilsGpuRes_t *request)
+{
+    nvSandboxUtilsRet_t (*fn)(nvSandboxUtilsGpuRes_t *) = dlsym(RTLD_DEFAULT, "nvSandboxUtilsGetGpuResource");
+    if (fn == NULL) {
+        return NVSANDBOXUTILS_ERROR_LIBRARY_LOAD;
+    }
+
+    return fn(request);
+}
+
+nvSandboxUtilsRet_t nvSandboxUtilsGetFileContent_dl(char *filePath, char *content, unsigned int *contentSize)
+{
+    nvSandboxUtilsRet_t (*fn)(char *, char *, unsigned int *) = dlsym(RTLD_DEFAULT, "nvSandboxUtilsGetFileContent");
+    if (fn == NULL) {
+        return NVSANDBOXUTILS_ERROR_LIBRARY_LOAD;
+    }
+
+    return fn(filePath, content, contentSize);
+}

internal/nvsandboxutils/dlsym_static.h

@@ -0,0 +1,28 @@
+/**
+# Copyright 2026 NVIDIA CORPORATION
+#
+# 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.
+**/
+
+#ifndef __NVSANDBOXUTILS_DLSYM_H__
+#define __NVSANDBOXUTILS_DLSYM_H__
+
+#include "nvsandboxutils.h"
+
+nvSandboxUtilsRet_t nvSandboxUtilsInit_dl(nvSandboxUtilsInitInput_t *input);
+nvSandboxUtilsRet_t nvSandboxUtilsShutdown_dl(void);
+nvSandboxUtilsRet_t nvSandboxUtilsGetDriverVersion_dl(char *version, unsigned int length);
+nvSandboxUtilsRet_t nvSandboxUtilsGetGpuResource_dl(nvSandboxUtilsGpuRes_t *request);
+nvSandboxUtilsRet_t nvSandboxUtilsGetFileContent_dl(char *filePath, char *content, unsigned int *contentSize);
+
+#endif // __NVSANDBOXUTILS_DLSYM_H__

internal/nvsandboxutils/gen/nvsandboxutils/nvsandboxutils.yml

@@ -30,12 +30,12 @@ GENERATOR:
     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.
-  Includes: ["nvsandboxutils.h"]
+  Includes: ["nvsandboxutils.h", "dlsym_static.h"]
   FlagGroups:
-    - {name: "LDFLAGS", traits: ["linux"], flags: ["-Wl,--export-dynamic","-Wl,--unresolved-symbols=ignore-in-object-files"]}
+    - {name: "LDFLAGS", traits: ["linux"], flags: ["-Wl,--export-dynamic"]}
     - {name: "LDFLAGS", traits: ["darwin"], flags: ["-Wl,-undefined,dynamic_lookup"]}
 PARSER:
-  SourcesPaths: ["nvsandboxutils.h"]
+  SourcesPaths: ["nvsandboxutils.h", "dlsym_static.h"]
 TRANSLATOR:
   ConstRules:
     defines: eval
@@ -62,5 +62,6 @@ TRANSLATOR:
       - {action: replace, from: "_t$"}
       - {transform: export}
     function:
-      - {action: accept, from: "^nvSandboxUtils"}
+      - {action: accept, from: "^nvSandboxUtils[[:alpha:]]+_dl$"}
+      - {action: replace, from: "_dl$"}
       - {transform: unexport}

internal/nvsandboxutils/nvsandboxutils_test.go

@@ -0,0 +1,191 @@
+/**
+# Copyright 2026 NVIDIA CORPORATION
+#
+# 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 nvsandboxutils
+
+import (
+	"os"
+	"os/exec"
+	"path/filepath"
+	"testing"
+
+	"github.com/stretchr/testify/require"
+)
+
+const (
+	mockRootfs        = "/mock/rootfs"
+	mockGpuUUID       = "GPU-6fd91e39-6ba7-4d6b-b1d6-1dffb0bc7a2f"
+	mockMigUUID       = "MIG-6fd91e39-6ba7-4d6b-b1d6-1dffb0bc7a2f"
+	mockDriverVersion = "999.88.77"
+
+	mockSymlinkPath   = "/dev/dri/by-path/pci-0000:41:00.0-card"
+	mockSymlinkTarget = "../card1"
+)
+
+func buildMockLibrary(t *testing.T) string {
+	t.Helper()
+
+	cc := os.Getenv("CC")
+	if cc == "" {
+		cc = "cc"
+	}
+	if _, err := exec.LookPath(cc); err != nil {
+		t.Skipf("no C compiler available: %v", err)
+	}
+
+	path := filepath.Join(t.TempDir(), "mock_nvsandbox.so")
+	cmd := exec.Command(cc, "-shared", "-fPIC", "-I", ".", "-o", path, filepath.Join("testdata", "mock_nvsandbox.c"))
+	output, err := cmd.CombinedOutput()
+	require.NoErrorf(t, err, "failed to build mock library: %s", output)
+
+	return path
+}
+
+func newMockLibrary(t *testing.T) *library {
+	t.Helper()
+
+	l := newLibrary(WithLibraryPath(buildMockLibrary(t)))
+	t.Cleanup(func() { _ = l.close() })
+
+	return l
+}
+
+func newInitializedMockLibrary(t *testing.T) *library {
+	t.Helper()
+
+	l := newMockLibrary(t)
+	require.Equal(t, SUCCESS, l.Init(mockRootfs))
+
+	return l
+}
+
+func TestEntryPointBeforeLoadReturnsLibraryLoadError(t *testing.T) {
+	require.Equal(t, ERROR_LIBRARY_LOAD, nvSandboxUtilsShutdown())
+}
+
+func TestInitRejectsAnUnexpectedRootfs(t *testing.T) {
+	l := newMockLibrary(t)
+
+	require.Equal(t, ERROR_INVALID_ARG, l.Init("/not/the/mock/rootfs"))
+}
+
+func TestGetDriverVersion(t *testing.T) {
+	l := newInitializedMockLibrary(t)
+
+	version, ret := l.GetDriverVersion()
+	require.Equal(t, SUCCESS, ret)
+	require.Equal(t, mockDriverVersion, version)
+}
+
+func TestGetFileContent(t *testing.T) {
+	testCases := []struct {
+		description     string
+		path            string
+		expectedContent string
+		expectedRet     Ret
+	}{
+		{
+			description:     "known path",
+			path:            mockSymlinkPath,
+			expectedContent: mockSymlinkTarget,
+			expectedRet:     SUCCESS,
+		},
+		{
+			description: "unknown path",
+			path:        "/not/a/known/path",
+			expectedRet: ERROR_FILEPATH_NOT_FOUND,
+		},
+	}
+
+	l := newInitializedMockLibrary(t)
+
+	for _, tc := range testCases {
+		t.Run(tc.description, func(t *testing.T) {
+			content, ret := l.GetFileContent(tc.path)
+			require.Equal(t, tc.expectedRet, ret)
+			if tc.expectedRet == SUCCESS {
+				require.Equal(t, tc.expectedContent, content)
+			}
+		})
+	}
+}
+
+func TestGetGpuResource(t *testing.T) {
+	testCases := []struct {
+		description string
+		uuid        string
+		expected    []GpuFileInfo
+		expectedRet Ret
+	}{
+		{
+			description: "GPU UUID returns the full list",
+			uuid:        mockGpuUUID,
+			expected: []GpuFileInfo{
+				{
+					Path:    "/dev/nvidia0",
+					Type:    NV_DEV,
+					SubType: NV_DEV_NVIDIA,
+					Module:  NV_GPU,
+					Flags:   NV_FILE_FLAG_HINT,
+				},
+				{
+					Path:    "/dev/nvidiactl",
+					Type:    NV_DEV,
+					SubType: NV_DEV_NVIDIA_CTL,
+					Module:  NV_DRIVER_NVIDIA,
+					Flags:   NV_FILE_FLAG_HINT,
+				},
+			},
+			expectedRet: SUCCESS,
+		},
+		{
+			description: "MIG UUID selects the MIG input type",
+			uuid:        mockMigUUID,
+			expected: []GpuFileInfo{
+				{
+					Path:    "/dev/nvidiactl",
+					Type:    NV_DEV,
+					SubType: NV_DEV_NVIDIA_CTL,
+					Module:  NV_DRIVER_NVIDIA,
+					Flags:   NV_FILE_FLAG_HINT,
+				},
+			},
+			expectedRet: SUCCESS,
+		},
+		{
+			description: "unknown UUID",
+			uuid:        "GPU-unknown",
+			expectedRet: ERROR_DEVICE_NOT_FOUND,
+		},
+	}
+
+	l := newInitializedMockLibrary(t)
+
+	for _, tc := range testCases {
+		t.Run(tc.description, func(t *testing.T) {
+			files, ret := l.GetGpuResource(tc.uuid)
+			require.Equal(t, tc.expectedRet, ret)
+			require.Equal(t, tc.expected, files)
+		})
+	}
+}
+
+func TestShutdownUnloadsTheLibrary(t *testing.T) {
+	l := newInitializedMockLibrary(t)
+
+	require.Equal(t, SUCCESS, l.Shutdown())
+	require.Equal(t, refcount(0), l.refcount)
+}