Merge branch 'ldcache-resolve-circular' into 'main'

Fix infinite recursion when resolving libraries in LDCache

Closes #13

See merge request nvidia/container-toolkit/container-toolkit!406

cmd/nvidia-ctk/info/info.go

@@ -35,13 +35,13 @@ func NewCommand(logger *logrus.Logger) *cli.Command {
 
 // build
 func (m command) build() *cli.Command {
-	// Create the 'hook' command
-	hook := cli.Command{
+	// Create the 'info' command
+	info := cli.Command{
 		Name:  "info",
 		Usage: "Provide information about the system",
 	}
 
-	hook.Subcommands = []*cli.Command{}
+	info.Subcommands = []*cli.Command{}
 
-	return &hook
+	return &info
 }

cmd/nvidia-ctk/system/print-ldcache/print-ldcache.go

@@ -0,0 +1,101 @@
+/**
+# Copyright (c) NVIDIA CORPORATION.  All rights reserved.
+#
+# 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 createdevicenodes
+
+import (
+	"fmt"
+
+	"github.com/NVIDIA/nvidia-container-toolkit/internal/ldcache"
+	"github.com/sirupsen/logrus"
+	"github.com/urfave/cli/v2"
+)
+
+type command struct {
+	logger *logrus.Logger
+}
+
+type options struct {
+	driverRoot string
+}
+
+// NewCommand constructs a command sub-command with the specified logger
+func NewCommand(logger *logrus.Logger) *cli.Command {
+	c := command{
+		logger: logger,
+	}
+	return c.build()
+}
+
+// build
+func (m command) build() *cli.Command {
+	opts := options{}
+
+	c := cli.Command{
+		Name:  "print-ldcache",
+		Usage: "A utility to print the contents of the ldcache",
+		Before: func(c *cli.Context) error {
+			return m.validateFlags(c, &opts)
+		},
+		Action: func(c *cli.Context) error {
+			return m.run(c, &opts)
+		},
+	}
+
+	c.Flags = []cli.Flag{
+		&cli.StringFlag{
+			Name:        "driver-root",
+			Usage:       "the path to the driver root. Device nodes will be created at `DRIVER_ROOT`/dev",
+			Value:       "/",
+			Destination: &opts.driverRoot,
+			EnvVars:     []string{"DRIVER_ROOT"},
+		},
+	}
+
+	return &c
+}
+
+func (m command) validateFlags(r *cli.Context, opts *options) error {
+	return nil
+}
+
+func (m command) run(c *cli.Context, opts *options) error {
+	cache, err := ldcache.New(m.logger, opts.driverRoot)
+	if err != nil {
+		return fmt.Errorf("failed to create ldcache: %v", err)
+	}
+
+	lib32, lib64 := cache.List()
+
+	if len(lib32) == 0 {
+		m.logger.Info("No 32-bit libraries found")
+	} else {
+		m.logger.Infof("%d 32-bit libraries found", len(lib32))
+		for _, lib := range lib32 {
+			m.logger.Infof("%v", lib)
+		}
+	}
+	if len(lib64) == 0 {
+		m.logger.Info("No 64-bit libraries found")
+	} else {
+		m.logger.Infof("%d 64-bit libraries found", len(lib64))
+		for _, lib := range lib64 {
+			m.logger.Infof("%v", lib)
+		}
+	}
+
+	return nil
+}

cmd/nvidia-ctk/system/system.go

@@ -19,6 +19,7 @@ package system
 import (
 	devchar "github.com/NVIDIA/nvidia-container-toolkit/cmd/nvidia-ctk/system/create-dev-char-symlinks"
 	devicenodes "github.com/NVIDIA/nvidia-container-toolkit/cmd/nvidia-ctk/system/create-device-nodes"
+	ldcache "github.com/NVIDIA/nvidia-container-toolkit/cmd/nvidia-ctk/system/print-ldcache"
 	"github.com/sirupsen/logrus"
 	"github.com/urfave/cli/v2"
 )
@@ -45,6 +46,7 @@ func (m command) build() *cli.Command {
 	system.Subcommands = []*cli.Command{
 		devchar.NewCommand(m.logger),
 		devicenodes.NewCommand(m.logger),
+		ldcache.NewCommand(m.logger),
 	}
 
 	return &system

internal/ldcache/ldcache.go

@@ -293,6 +293,9 @@ func (c *ldcache) resolve(target string) (string, error) {
 	if err != nil {
 		return "", fmt.Errorf("failed to resolve symlink: %v", err)
 	}
+	if link == name {
+		return name, nil
+	}
 
 	// We return absolute paths for all targets
 	if !filepath.IsAbs(link) || strings.HasPrefix(link, ".") {