From 927ec78b6e7002dc11b4432e50e41d881960766b Mon Sep 17 00:00:00 2001 From: Evan Lezar Date: Thu, 11 May 2023 14:04:16 +0200 Subject: [PATCH] Add symlinks package with Resolve function This change adds a symlinks.Resolve function for resolving symlinks and updates usages across the code to make use of it. Signed-off-by: Evan Lezar --- .../hook/create-symlinks/create-symlinks.go | 12 +++---- internal/ldcache/ldcache.go | 12 ++----- internal/lookup/symlinks.go | 13 ++----- internal/lookup/symlinks/symlink.go | 35 +++++++++++++++++++ 4 files changed, 45 insertions(+), 27 deletions(-) create mode 100644 internal/lookup/symlinks/symlink.go diff --git a/cmd/nvidia-ctk/hook/create-symlinks/create-symlinks.go b/cmd/nvidia-ctk/hook/create-symlinks/create-symlinks.go index 8fe92e32..39ade7f0 100644 --- a/cmd/nvidia-ctk/hook/create-symlinks/create-symlinks.go +++ b/cmd/nvidia-ctk/hook/create-symlinks/create-symlinks.go @@ -24,6 +24,7 @@ import ( "github.com/NVIDIA/nvidia-container-toolkit/internal/discover/csv" "github.com/NVIDIA/nvidia-container-toolkit/internal/lookup" + "github.com/NVIDIA/nvidia-container-toolkit/internal/lookup/symlinks" "github.com/NVIDIA/nvidia-container-toolkit/internal/oci" "github.com/sirupsen/logrus" "github.com/urfave/cli/v2" @@ -125,21 +126,18 @@ func (m command) run(c *cli.Context, cfg *config) error { created := make(map[string]bool) // candidates is a list of absolute paths to symlinks in a chain, or the final target of the chain. for _, candidate := range candidates { - targets, err := m.Locate(candidate) + target, err := symlinks.Resolve(candidate) if err != nil { m.logger.Debugf("Skipping invalid link: %v", err) continue - } else if len(targets) != 1 { - m.logger.Debugf("Unexepected number of targets: %v", targets) - continue - } else if targets[0] == candidate { + } else if target == candidate { m.logger.Debugf("%v is not a symlink", candidate) continue } - err = m.createLink(created, cfg.hostRoot, containerRoot, targets[0], candidate) + err = m.createLink(created, cfg.hostRoot, containerRoot, target, candidate) if err != nil { - m.logger.Warnf("Failed to create link %v: %v", []string{targets[0], candidate}, err) + m.logger.Warnf("Failed to create link %v: %v", []string{target, candidate}, err) } } diff --git a/internal/ldcache/ldcache.go b/internal/ldcache/ldcache.go index 5493dc31..1fe7d074 100644 --- a/internal/ldcache/ldcache.go +++ b/internal/ldcache/ldcache.go @@ -29,6 +29,7 @@ import ( "syscall" "unsafe" + "github.com/NVIDIA/nvidia-container-toolkit/internal/lookup/symlinks" log "github.com/sirupsen/logrus" ) @@ -288,16 +289,7 @@ func (c *ldcache) resolve(target string) (string, error) { c.logger.Debugf("checking %v", string(name)) - info, err := os.Lstat(name) - if err != nil { - return "", fmt.Errorf("failed to get file info: %v", info) - } - if info.Mode()&os.ModeSymlink == 0 { - c.logger.Debugf("Resolved regular file: %v", name) - return name, nil - } - - link, err := os.Readlink(name) + link, err := symlinks.Resolve(name) if err != nil { return "", fmt.Errorf("failed to resolve symlink: %v", err) } diff --git a/internal/lookup/symlinks.go b/internal/lookup/symlinks.go index 0d82a9e1..438e42d5 100644 --- a/internal/lookup/symlinks.go +++ b/internal/lookup/symlinks.go @@ -18,9 +18,9 @@ package lookup import ( "fmt" - "os" "path/filepath" + "github.com/NVIDIA/nvidia-container-toolkit/internal/lookup/symlinks" "github.com/sirupsen/logrus" ) @@ -74,16 +74,9 @@ func (p symlinkChain) Locate(pattern string) ([]string, error) { } found[candidate] = true - info, err := os.Lstat(candidate) + target, err := symlinks.Resolve(candidate) if err != nil { - return nil, fmt.Errorf("failed to get file info: %v", info) - } - if info.Mode()&os.ModeSymlink == 0 { - continue - } - target, err := os.Readlink(candidate) - if err != nil { - return nil, fmt.Errorf("error checking symlink: %v", err) + return nil, fmt.Errorf("error resolving symlink: %v", err) } if !filepath.IsAbs(target) { diff --git a/internal/lookup/symlinks/symlink.go b/internal/lookup/symlinks/symlink.go new file mode 100644 index 00000000..991d47cb --- /dev/null +++ b/internal/lookup/symlinks/symlink.go @@ -0,0 +1,35 @@ +/** +# 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 symlinks + +import ( + "fmt" + "os" +) + +// Resolve returns the link target of the specified filename or the filename if it is not a link. +func Resolve(filename string) (string, error) { + info, err := os.Lstat(filename) + if err != nil { + return filename, fmt.Errorf("failed to get file info: %v", info) + } + if info.Mode()&os.ModeSymlink == 0 { + return filename, nil + } + + return os.Readlink(filename) +}