From 588f040a77c7998787396dba45aeee003d63f77b Mon Sep 17 00:00:00 2001 From: Filipe Brandenburger Date: Thu, 22 Aug 2019 21:07:24 -0700 Subject: [PATCH 1/2] Avoid the dependency on cgo through go-systemd/util package This dependency is only needed in package "github.com/coreos/go-systemd/util" and we only use it for IsRunningSystemd(), which is a simple Go function that just stats a file. Let's just borrow it here, so we remove the dependency and can remove that package from vendored build. This also removes dependencies on dlopen and on trying to find libsystemd.so or libsystemd-login.so in the system. Tested that this still builds and works as expected. Signed-off-by: Filipe Brandenburger --- libcontainer/cgroups/systemd/apply_systemd.go | 20 ++++++++++++++++--- 1 file changed, 17 insertions(+), 3 deletions(-) diff --git a/libcontainer/cgroups/systemd/apply_systemd.go b/libcontainer/cgroups/systemd/apply_systemd.go index 3bf723bf964..436c0200cbe 100644 --- a/libcontainer/cgroups/systemd/apply_systemd.go +++ b/libcontainer/cgroups/systemd/apply_systemd.go @@ -14,7 +14,6 @@ import ( "time" systemdDbus "github.com/coreos/go-systemd/dbus" - systemdUtil "github.com/coreos/go-systemd/util" "github.com/godbus/dbus" "github.com/opencontainers/runc/libcontainer/cgroups" "github.com/opencontainers/runc/libcontainer/cgroups/fs" @@ -86,8 +85,23 @@ func newProp(name string, units interface{}) systemdDbus.Property { } } +// NOTE: This function comes from package github.com/coreos/go-systemd/util +// It was borrowed here to avoid a dependency on cgo. +// +// IsRunningSystemd checks whether the host was booted with systemd as its init +// system. This functions similarly to systemd's `sd_booted(3)`: internally, it +// checks whether /run/systemd/system/ exists and is a directory. +// http://www.freedesktop.org/software/systemd/man/sd_booted.html +func isRunningSystemd() bool { + fi, err := os.Lstat("/run/systemd/system") + if err != nil { + return false + } + return fi.IsDir() +} + func UseSystemd() bool { - if !systemdUtil.IsRunningSystemd() { + if !isRunningSystemd() { return false } @@ -164,7 +178,7 @@ func UseSystemd() bool { } func NewSystemdCgroupsManager() (func(config *configs.Cgroup, paths map[string]string) cgroups.Manager, error) { - if !systemdUtil.IsRunningSystemd() { + if !isRunningSystemd() { return nil, fmt.Errorf("systemd not running on this host, can't use systemd as a cgroups.Manager") } return func(config *configs.Cgroup, paths map[string]string) cgroups.Manager { From 4ca00773eee9c20a0e99e53458e86684bcae6060 Mon Sep 17 00:00:00 2001 From: Filipe Brandenburger Date: Thu, 22 Aug 2019 21:09:40 -0700 Subject: [PATCH 2/2] Update vendored dependencies to remove go-systemd/util This removes "github.com/coreos/go-systemd/util", no longer needed after removing the dependency on it. It also gets rid of "github.com/coreos/pkg/dlopen", since that was only referred to by the aforementioned "util" package. Tested that everything builds and works as expected. Signed-off-by: Filipe Brandenburger --- vendor.conf | 1 - .../github.com/coreos/go-systemd/util/util.go | 90 -------- .../coreos/go-systemd/util/util_cgo.go | 174 --------------- .../coreos/go-systemd/util/util_stub.go | 23 -- vendor/github.com/coreos/pkg/LICENSE | 202 ------------------ vendor/github.com/coreos/pkg/NOTICE | 5 - vendor/github.com/coreos/pkg/README.md | 4 - vendor/github.com/coreos/pkg/dlopen/dlopen.go | 82 ------- .../coreos/pkg/dlopen/dlopen_example.go | 56 ----- 9 files changed, 637 deletions(-) delete mode 100644 vendor/github.com/coreos/go-systemd/util/util.go delete mode 100644 vendor/github.com/coreos/go-systemd/util/util_cgo.go delete mode 100644 vendor/github.com/coreos/go-systemd/util/util_stub.go delete mode 100644 vendor/github.com/coreos/pkg/LICENSE delete mode 100644 vendor/github.com/coreos/pkg/NOTICE delete mode 100644 vendor/github.com/coreos/pkg/README.md delete mode 100644 vendor/github.com/coreos/pkg/dlopen/dlopen.go delete mode 100644 vendor/github.com/coreos/pkg/dlopen/dlopen_example.go diff --git a/vendor.conf b/vendor.conf index b0bfb1ef83b..11abc94334d 100644 --- a/vendor.conf +++ b/vendor.conf @@ -12,7 +12,6 @@ github.com/syndtr/gocapability db04d3cc01c8b54962a58ec7e491717d06cfcc16 github.com/vishvananda/netlink 1e2e08e8a2dcdacaae3f14ac44c5cfa31361f270 # systemd integration. github.com/coreos/go-systemd v14 -github.com/coreos/pkg v3 github.com/godbus/dbus v3 github.com/golang/protobuf 18c9bb3261723cd5401db4d0c9fbc5c3b6c70fe8 # Command-line interface. diff --git a/vendor/github.com/coreos/go-systemd/util/util.go b/vendor/github.com/coreos/go-systemd/util/util.go deleted file mode 100644 index 7828ce6f049..00000000000 --- a/vendor/github.com/coreos/go-systemd/util/util.go +++ /dev/null @@ -1,90 +0,0 @@ -// Copyright 2015 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 util contains utility functions related to systemd that applications -// can use to check things like whether systemd is running. Note that some of -// these functions attempt to manually load systemd libraries at runtime rather -// than linking against them. -package util - -import ( - "fmt" - "io/ioutil" - "os" - "strings" -) - -var ( - ErrNoCGO = fmt.Errorf("go-systemd built with CGO disabled") -) - -// GetRunningSlice attempts to retrieve the name of the systemd slice in which -// the current process is running. -// This function is a wrapper around the libsystemd C library; if it cannot be -// opened, an error is returned. -func GetRunningSlice() (string, error) { - return getRunningSlice() -} - -// RunningFromSystemService tries to detect whether the current process has -// been invoked from a system service. The condition for this is whether the -// process is _not_ a user process. User processes are those running in session -// scopes or under per-user `systemd --user` instances. -// -// To avoid false positives on systems without `pam_systemd` (which is -// responsible for creating user sessions), this function also uses a heuristic -// to detect whether it's being invoked from a session leader process. This is -// the case if the current process is executed directly from a service file -// (e.g. with `ExecStart=/this/cmd`). Note that this heuristic will fail if the -// command is instead launched in a subshell or similar so that it is not -// session leader (e.g. `ExecStart=/bin/bash -c "/this/cmd"`) -// -// This function is a wrapper around the libsystemd C library; if this is -// unable to successfully open a handle to the library for any reason (e.g. it -// cannot be found), an error will be returned. -func RunningFromSystemService() (bool, error) { - return runningFromSystemService() -} - -// CurrentUnitName attempts to retrieve the name of the systemd system unit -// from which the calling process has been invoked. It wraps the systemd -// `sd_pid_get_unit` call, with the same caveat: for processes not part of a -// systemd system unit, this function will return an error. -func CurrentUnitName() (string, error) { - return currentUnitName() -} - -// IsRunningSystemd checks whether the host was booted with systemd as its init -// system. This functions similarly to systemd's `sd_booted(3)`: internally, it -// checks whether /run/systemd/system/ exists and is a directory. -// http://www.freedesktop.org/software/systemd/man/sd_booted.html -func IsRunningSystemd() bool { - fi, err := os.Lstat("/run/systemd/system") - if err != nil { - return false - } - return fi.IsDir() -} - -// GetMachineID returns a host's 128-bit machine ID as a string. This functions -// similarly to systemd's `sd_id128_get_machine`: internally, it simply reads -// the contents of /etc/machine-id -// http://www.freedesktop.org/software/systemd/man/sd_id128_get_machine.html -func GetMachineID() (string, error) { - machineID, err := ioutil.ReadFile("/etc/machine-id") - if err != nil { - return "", fmt.Errorf("failed to read /etc/machine-id: %v", err) - } - return strings.TrimSpace(string(machineID)), nil -} diff --git a/vendor/github.com/coreos/go-systemd/util/util_cgo.go b/vendor/github.com/coreos/go-systemd/util/util_cgo.go deleted file mode 100644 index 22c0d6099df..00000000000 --- a/vendor/github.com/coreos/go-systemd/util/util_cgo.go +++ /dev/null @@ -1,174 +0,0 @@ -// 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. - -// +build cgo - -package util - -// #include -// #include -// #include -// -// int -// my_sd_pid_get_owner_uid(void *f, pid_t pid, uid_t *uid) -// { -// int (*sd_pid_get_owner_uid)(pid_t, uid_t *); -// -// sd_pid_get_owner_uid = (int (*)(pid_t, uid_t *))f; -// return sd_pid_get_owner_uid(pid, uid); -// } -// -// int -// my_sd_pid_get_unit(void *f, pid_t pid, char **unit) -// { -// int (*sd_pid_get_unit)(pid_t, char **); -// -// sd_pid_get_unit = (int (*)(pid_t, char **))f; -// return sd_pid_get_unit(pid, unit); -// } -// -// int -// my_sd_pid_get_slice(void *f, pid_t pid, char **slice) -// { -// int (*sd_pid_get_slice)(pid_t, char **); -// -// sd_pid_get_slice = (int (*)(pid_t, char **))f; -// return sd_pid_get_slice(pid, slice); -// } -// -// int -// am_session_leader() -// { -// return (getsid(0) == getpid()); -// } -import "C" -import ( - "fmt" - "syscall" - "unsafe" - - "github.com/coreos/pkg/dlopen" -) - -var libsystemdNames = []string{ - // systemd < 209 - "libsystemd-login.so.0", - "libsystemd-login.so", - - // systemd >= 209 merged libsystemd-login into libsystemd proper - "libsystemd.so.0", - "libsystemd.so", -} - -func getRunningSlice() (slice string, err error) { - var h *dlopen.LibHandle - h, err = dlopen.GetHandle(libsystemdNames) - if err != nil { - return - } - defer func() { - if err1 := h.Close(); err1 != nil { - err = err1 - } - }() - - sd_pid_get_slice, err := h.GetSymbolPointer("sd_pid_get_slice") - if err != nil { - return - } - - var s string - sl := C.CString(s) - defer C.free(unsafe.Pointer(sl)) - - ret := C.my_sd_pid_get_slice(sd_pid_get_slice, 0, &sl) - if ret < 0 { - err = fmt.Errorf("error calling sd_pid_get_slice: %v", syscall.Errno(-ret)) - return - } - - return C.GoString(sl), nil -} - -func runningFromSystemService() (ret bool, err error) { - var h *dlopen.LibHandle - h, err = dlopen.GetHandle(libsystemdNames) - if err != nil { - return - } - defer func() { - if err1 := h.Close(); err1 != nil { - err = err1 - } - }() - - sd_pid_get_owner_uid, err := h.GetSymbolPointer("sd_pid_get_owner_uid") - if err != nil { - return - } - - var uid C.uid_t - errno := C.my_sd_pid_get_owner_uid(sd_pid_get_owner_uid, 0, &uid) - serrno := syscall.Errno(-errno) - // when we're running from a unit file, sd_pid_get_owner_uid returns - // ENOENT (systemd <220) or ENXIO (systemd >=220) - switch { - case errno >= 0: - ret = false - case serrno == syscall.ENOENT, serrno == syscall.ENXIO: - // Since the implementation of sessions in systemd relies on - // the `pam_systemd` module, using the sd_pid_get_owner_uid - // heuristic alone can result in false positives if that module - // (or PAM itself) is not present or properly configured on the - // system. As such, we also check if we're the session leader, - // which should be the case if we're invoked from a unit file, - // but not if e.g. we're invoked from the command line from a - // user's login session - ret = C.am_session_leader() == 1 - default: - err = fmt.Errorf("error calling sd_pid_get_owner_uid: %v", syscall.Errno(-errno)) - } - return -} - -func currentUnitName() (unit string, err error) { - var h *dlopen.LibHandle - h, err = dlopen.GetHandle(libsystemdNames) - if err != nil { - return - } - defer func() { - if err1 := h.Close(); err1 != nil { - err = err1 - } - }() - - sd_pid_get_unit, err := h.GetSymbolPointer("sd_pid_get_unit") - if err != nil { - return - } - - var s string - u := C.CString(s) - defer C.free(unsafe.Pointer(u)) - - ret := C.my_sd_pid_get_unit(sd_pid_get_unit, 0, &u) - if ret < 0 { - err = fmt.Errorf("error calling sd_pid_get_unit: %v", syscall.Errno(-ret)) - return - } - - unit = C.GoString(u) - return -} diff --git a/vendor/github.com/coreos/go-systemd/util/util_stub.go b/vendor/github.com/coreos/go-systemd/util/util_stub.go deleted file mode 100644 index 477589e1227..00000000000 --- a/vendor/github.com/coreos/go-systemd/util/util_stub.go +++ /dev/null @@ -1,23 +0,0 @@ -// 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. - -// +build !cgo - -package util - -func getRunningSlice() (string, error) { return "", ErrNoCGO } - -func runningFromSystemService() (bool, error) { return false, ErrNoCGO } - -func currentUnitName() (string, error) { return "", ErrNoCGO } diff --git a/vendor/github.com/coreos/pkg/LICENSE b/vendor/github.com/coreos/pkg/LICENSE deleted file mode 100644 index e06d2081865..00000000000 --- a/vendor/github.com/coreos/pkg/LICENSE +++ /dev/null @@ -1,202 +0,0 @@ -Apache License - Version 2.0, January 2004 - http://www.apache.org/licenses/ - - TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION - - 1. Definitions. - - "License" shall mean the terms and conditions for use, reproduction, - and distribution as defined by Sections 1 through 9 of this document. - - "Licensor" shall mean the copyright owner or entity authorized by - the copyright owner that is granting the License. - - "Legal Entity" shall mean the union of the acting entity and all - other entities that control, are controlled by, or are under common - control with that entity. For the purposes of this definition, - "control" means (i) the power, direct or indirect, to cause the - direction or management of such entity, whether by contract or - otherwise, or (ii) ownership of fifty percent (50%) or more of the - outstanding shares, or (iii) beneficial ownership of such entity. - - "You" (or "Your") shall mean an individual or Legal Entity - exercising permissions granted by this License. - - "Source" form shall mean the preferred form for making modifications, - including but not limited to software source code, documentation - source, and configuration files. - - "Object" form shall mean any form resulting from mechanical - transformation or translation of a Source form, including but - not limited to compiled object code, generated documentation, - and conversions to other media types. - - "Work" shall mean the work of authorship, whether in Source or - Object form, made available under the License, as indicated by a - copyright notice that is included in or attached to the work - (an example is provided in the Appendix below). - - "Derivative Works" shall mean any work, whether in Source or Object - form, that is based on (or derived from) the Work and for which the - editorial revisions, annotations, elaborations, or other modifications - represent, as a whole, an original work of authorship. For the purposes - of this License, Derivative Works shall not include works that remain - separable from, or merely link (or bind by name) to the interfaces of, - the Work and Derivative Works thereof. - - "Contribution" shall mean any work of authorship, including - the original version of the Work and any modifications or additions - to that Work or Derivative Works thereof, that is intentionally - submitted to Licensor for inclusion in the Work by the copyright owner - or by an individual or Legal Entity authorized to submit on behalf of - the copyright owner. For the purposes of this definition, "submitted" - means any form of electronic, verbal, or written communication sent - to the Licensor or its representatives, including but not limited to - communication on electronic mailing lists, source code control systems, - and issue tracking systems that are managed by, or on behalf of, the - Licensor for the purpose of discussing and improving the Work, but - excluding communication that is conspicuously marked or otherwise - designated in writing by the copyright owner as "Not a Contribution." - - "Contributor" shall mean Licensor and any individual or Legal Entity - on behalf of whom a Contribution has been received by Licensor and - subsequently incorporated within the Work. - - 2. Grant of Copyright License. Subject to the terms and conditions of - this License, each Contributor hereby grants to You a perpetual, - worldwide, non-exclusive, no-charge, royalty-free, irrevocable - copyright license to reproduce, prepare Derivative Works of, - publicly display, publicly perform, sublicense, and distribute the - Work and such Derivative Works in Source or Object form. - - 3. Grant of Patent License. Subject to the terms and conditions of - this License, each Contributor hereby grants to You a perpetual, - worldwide, non-exclusive, no-charge, royalty-free, irrevocable - (except as stated in this section) patent license to make, have made, - use, offer to sell, sell, import, and otherwise transfer the Work, - where such license applies only to those patent claims licensable - by such Contributor that are necessarily infringed by their - Contribution(s) alone or by combination of their Contribution(s) - with the Work to which such Contribution(s) was submitted. If You - institute patent litigation against any entity (including a - cross-claim or counterclaim in a lawsuit) alleging that the Work - or a Contribution incorporated within the Work constitutes direct - or contributory patent infringement, then any patent licenses - granted to You under this License for that Work shall terminate - as of the date such litigation is filed. - - 4. Redistribution. You may reproduce and distribute copies of the - Work or Derivative Works thereof in any medium, with or without - modifications, and in Source or Object form, provided that You - meet the following conditions: - - (a) You must give any other recipients of the Work or - Derivative Works a copy of this License; and - - (b) You must cause any modified files to carry prominent notices - stating that You changed the files; and - - (c) You must retain, in the Source form of any Derivative Works - that You distribute, all copyright, patent, trademark, and - attribution notices from the Source form of the Work, - excluding those notices that do not pertain to any part of - the Derivative Works; and - - (d) If the Work includes a "NOTICE" text file as part of its - distribution, then any Derivative Works that You distribute must - include a readable copy of the attribution notices contained - within such NOTICE file, excluding those notices that do not - pertain to any part of the Derivative Works, in at least one - of the following places: within a NOTICE text file distributed - as part of the Derivative Works; within the Source form or - documentation, if provided along with the Derivative Works; or, - within a display generated by the Derivative Works, if and - wherever such third-party notices normally appear. The contents - of the NOTICE file are for informational purposes only and - do not modify the License. You may add Your own attribution - notices within Derivative Works that You distribute, alongside - or as an addendum to the NOTICE text from the Work, provided - that such additional attribution notices cannot be construed - as modifying the License. - - You may add Your own copyright statement to Your modifications and - may provide additional or different license terms and conditions - for use, reproduction, or distribution of Your modifications, or - for any such Derivative Works as a whole, provided Your use, - reproduction, and distribution of the Work otherwise complies with - the conditions stated in this License. - - 5. Submission of Contributions. Unless You explicitly state otherwise, - any Contribution intentionally submitted for inclusion in the Work - by You to the Licensor shall be under the terms and conditions of - this License, without any additional terms or conditions. - Notwithstanding the above, nothing herein shall supersede or modify - the terms of any separate license agreement you may have executed - with Licensor regarding such Contributions. - - 6. Trademarks. This License does not grant permission to use the trade - names, trademarks, service marks, or product names of the Licensor, - except as required for reasonable and customary use in describing the - origin of the Work and reproducing the content of the NOTICE file. - - 7. Disclaimer of Warranty. Unless required by applicable law or - agreed to in writing, Licensor provides the Work (and each - Contributor provides its Contributions) on an "AS IS" BASIS, - WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or - implied, including, without limitation, any warranties or conditions - of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A - PARTICULAR PURPOSE. You are solely responsible for determining the - appropriateness of using or redistributing the Work and assume any - risks associated with Your exercise of permissions under this License. - - 8. Limitation of Liability. In no event and under no legal theory, - whether in tort (including negligence), contract, or otherwise, - unless required by applicable law (such as deliberate and grossly - negligent acts) or agreed to in writing, shall any Contributor be - liable to You for damages, including any direct, indirect, special, - incidental, or consequential damages of any character arising as a - result of this License or out of the use or inability to use the - Work (including but not limited to damages for loss of goodwill, - work stoppage, computer failure or malfunction, or any and all - other commercial damages or losses), even if such Contributor - has been advised of the possibility of such damages. - - 9. Accepting Warranty or Additional Liability. While redistributing - the Work or Derivative Works thereof, You may choose to offer, - and charge a fee for, acceptance of support, warranty, indemnity, - or other liability obligations and/or rights consistent with this - License. However, in accepting such obligations, You may act only - on Your own behalf and on Your sole responsibility, not on behalf - of any other Contributor, and only if You agree to indemnify, - defend, and hold each Contributor harmless for any liability - incurred by, or claims asserted against, such Contributor by reason - of your accepting any such warranty or additional liability. - - END OF TERMS AND CONDITIONS - - APPENDIX: How to apply the Apache License to your work. - - To apply the Apache License to your work, attach the following - boilerplate notice, with the fields enclosed by brackets "{}" - replaced with your own identifying information. (Don't include - the brackets!) The text should be enclosed in the appropriate - comment syntax for the file format. We also recommend that a - file or class name and description of purpose be included on the - same "printed page" as the copyright notice for easier - identification within third-party archives. - - Copyright {yyyy} {name of copyright owner} - - 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. - diff --git a/vendor/github.com/coreos/pkg/NOTICE b/vendor/github.com/coreos/pkg/NOTICE deleted file mode 100644 index b39ddfa5cbd..00000000000 --- a/vendor/github.com/coreos/pkg/NOTICE +++ /dev/null @@ -1,5 +0,0 @@ -CoreOS Project -Copyright 2014 CoreOS, Inc - -This product includes software developed at CoreOS, Inc. -(http://www.coreos.com/). diff --git a/vendor/github.com/coreos/pkg/README.md b/vendor/github.com/coreos/pkg/README.md deleted file mode 100644 index ca68a07f0fa..00000000000 --- a/vendor/github.com/coreos/pkg/README.md +++ /dev/null @@ -1,4 +0,0 @@ -a collection of go utility packages - -[![Build Status](https://travis-ci.org/coreos/pkg.png?branch=master)](https://travis-ci.org/coreos/pkg) -[![Godoc](http://img.shields.io/badge/godoc-reference-blue.svg?style=flat)](https://godoc.org/github.com/coreos/pkg) diff --git a/vendor/github.com/coreos/pkg/dlopen/dlopen.go b/vendor/github.com/coreos/pkg/dlopen/dlopen.go deleted file mode 100644 index 23774f612e0..00000000000 --- a/vendor/github.com/coreos/pkg/dlopen/dlopen.go +++ /dev/null @@ -1,82 +0,0 @@ -// 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 -// #include -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 -} diff --git a/vendor/github.com/coreos/pkg/dlopen/dlopen_example.go b/vendor/github.com/coreos/pkg/dlopen/dlopen_example.go deleted file mode 100644 index 48a660104fb..00000000000 --- a/vendor/github.com/coreos/pkg/dlopen/dlopen_example.go +++ /dev/null @@ -1,56 +0,0 @@ -// Copyright 2015 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. -// -// +build linux - -package dlopen - -// #include -// #include -// -// int -// my_strlen(void *f, const char *s) -// { -// size_t (*strlen)(const char *); -// -// strlen = (size_t (*)(const char *))f; -// return strlen(s); -// } -import "C" - -import ( - "fmt" - "unsafe" -) - -func strlen(libs []string, s string) (int, error) { - h, err := GetHandle(libs) - if err != nil { - return -1, fmt.Errorf(`couldn't get a handle to the library: %v`, err) - } - defer h.Close() - - f := "strlen" - cs := C.CString(s) - defer C.free(unsafe.Pointer(cs)) - - strlen, err := h.GetSymbolPointer(f) - if err != nil { - return -1, fmt.Errorf(`couldn't get symbol %q: %v`, f, err) - } - - len := C.my_strlen(strlen, cs) - - return int(len), nil -}