Adding upstream version 115.7.0esr.upstream/115.7.0esr

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

12 files changed, 1835 insertions, 0 deletions

diff --git a/third_party/rust/pkg-config/.cargo-checksum.json b/third_party/rust/pkg-config/.cargo-checksum.json
new file mode 100644
index 0000000000..c5e73aa5cb
--- /dev/null
+++ b/third_party/rust/pkg-config/.cargo-checksum.json
@@ -0,0 +1 @@
+{"files":{"CHANGELOG.md":"bc1a9e53c60e64a9f30e81109eeae1273ee1f574291ff712c2cfa0ec78155c82","Cargo.toml":"e2faa7f58ba9688a2f1ab2708632b4f13d0c87e769c5909b7a30facad4d648de","LICENSE-APACHE":"a60eea817514531668d7e00765731449fe14d059d3249e0bc93b36de45f759f2","LICENSE-MIT":"378f5840b258e2779c39418f3f2d7b2ba96f1c7917dd6be0713f88305dbda397","README.md":"37f11a56c969237dcfd15368e96bf686ec92b0254e38fb84636e178d632c0492","src/lib.rs":"04de2653405cdbe3c662fb8e31ea3dcab7431b32dbfbd3243075de6cb5f84588","tests/escape.pc":"00caa4136799dbe5bd504239ba90d1156c12def365c8d761da319fe8a83b398e","tests/foo.pc":"4a1c442c5d1c10761ea1644f8fd58f93cc5a706391bc67b04c243bbd35d70d79","tests/framework.pc":"304fdb6cea92973650e410ab1f70ce1ebeb7718af3f139e806efbf182acd565c","tests/rpath.pc":"424a844e844edfef02692492def9864833391f581338962946646989a69c1180","tests/test.rs":"dc0c27302c599524c06be5b807e8e371f60c8296e9da280677c79db1a3fe146a"},"package":"6ac9a59f73473f1b8d852421e59e64809f025994837ef743615c6d0c5b305160"}
\ No newline at end of file
diff --git a/third_party/rust/pkg-config/CHANGELOG.md b/third_party/rust/pkg-config/CHANGELOG.md
new file mode 100644
index 0000000000..3ea463d030
--- /dev/null
+++ b/third_party/rust/pkg-config/CHANGELOG.md
@@ -0,0 +1,163 @@
+# Changelog
+
+All notable changes to this project will be documented in this file.
+
+The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/)
+and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
+
+## [0.3.26] - 2022-10-26
+
+### Added
+
+- Support for handling full paths to libraries in addition to normal `-l`
+  linker flags (#134).
+
+## [0.3.25] - 2022-03-31
+
+### Added
+
+- Support for parsing `-Wl` linker arguments from the `Libs` lines and
+  passing them to the linker as well as making them available via
+  `Library::ld_args` (#131).
+
+### Changed
+
+- Use SPDX license format and remove obsolete badge info (#129).
+
+## [0.3.24] - 2021-12-11
+
+### Fixed
+
+- Re-add `target_supported()`, which was accidentally removed in 0.3.15 (#128).
+
+## [0.3.23] - 2021-12-06
+
+### Changed
+
+- Improve error messages when a `pkg-config` package can't be found (#127).
+
+## [0.3.22] - 2021-10-24
+
+### Fixed
+
+- `pkg-config` compiles again with Rust 1.30 or newer. 0.3.21 accidentally
+  made use of API only available since 1.40 (#124, #125).
+
+### Changed
+
+- Switched from Travis to GitHub Actions for the CI. Travis is dysfunctional
+  since quite some time (#126).
+
+## [0.3.21] - 2021-10-22
+
+### Fixed
+
+- Tests succeed again on macOS (#122).
+
+### Changed
+
+- Improve error message in case of missing pkg-config and provide instructions
+  how it can be installed (#121).
+
+## [0.3.20] - 2021-09-25
+
+### Fixed
+
+- Use target-specific pkg-config consistently everywhere (#121, #118).
+
+## [0.3.19] - 2020-10-13
+
+### Added
+
+- Add `README.md` to be displayed on crates.io (#111).
+
+- Support for `-isystem`, `-iquote` and `-idirafter` include flags (#115).
+
+### Changed
+
+- Improve documentation for cross-compilation (#113).
+
+- Allow overriding system root via the `PKG_CONFIG_SYSROOT_DIR` or `SYSROOT`
+  environment variable (#82).
+
+## [0.3.18] - 2020-07-11
+
+### Fixed
+
+- Use `env::var_os()` almost everywhere to handle non-UTF8 paths in
+  environment variables, and also improve error handling around environment
+  variable handling (#106).
+
+### Changed
+
+- Default the `env_metadata` build parameter to `true` instead of `false`.
+  Whenever a pkg-config related environment variable changes it would make
+  sense to rebuild crates that use pkg-config, or otherwise changes might not
+  be picked up. As such the previous default didn't make much sense (#105).
+
+## [0.3.17] - 2019-11-02
+
+### Fixed
+
+- Fix support for multiple version number constraints (#95)
+
+## [0.3.16] - 2019-09-09
+
+### Changed
+- Stop using deprecated functions and require Rust 1.30 (#84)
+
+### Fixed
+- Fix repository URL in README.md
+- Fix various clippy warnings
+
+### Added
+- Run `cargo fmt` as part of the CI (#89)
+- Derive `Clone` for `Library` and `Debug` for `Config (#91)
+- Add support for `PKG_CONFIG_ALLOW_SYSTEM_CFLAGS` and enable by default (#93)
+
+## [0.3.15] - 2019-07-25
+
+### Changed
+- Changes minimum documented rust version to 1.28 (#76)
+
+### Fixed
+- Fix Travis CI badge url (#78)
+- Fix project name in README.md (#81)
+
+### Added
+- Support specifying range of versions (#75)
+- Allow cross-compilation if pkg-config is customized (#44, #86)
+
+## [0.3.14] - 2018-08-28
+
+### Fixed
+- Don't append .lib suffix on MSVC builds (#72)
+
+## [0.3.13] - 2018-08-06
+
+### Fixed
+- Fix MSVC support to actually work and consider library paths too (#71)
+
+## [0.3.12] - 2018-06-18
+
+### Added
+- Support for MSVC (#70)
+- Document and test Rust 1.13 as minimally supported version (#66)
+
+## [0.3.11] - 2018-04-24
+
+### Fixed
+- Re-added AsciiExt import (#65)
+
+## [0.3.10] - 2018-04-23
+
+### Added
+- Allow static linking of /usr/ on macOS (#42)
+- Add support for parsing `-Wl,` style framework flags (#48)
+- Parse defines in `pkg-config` output (#49)
+- Rerun on `PKG_CONFIG_PATH` changes (#50)
+- Introduce target-scoped variables (#58)
+- Respect pkg-config escaping rules used with --cflags and --libs (#61)
+
+### Changed
+- Use `?` instead of `try!()` in the codebase (#63)
diff --git a/third_party/rust/pkg-config/Cargo.toml b/third_party/rust/pkg-config/Cargo.toml
new file mode 100644
index 0000000000..abd63e3d7a
--- /dev/null
+++ b/third_party/rust/pkg-config/Cargo.toml
@@ -0,0 +1,27 @@
+# THIS FILE IS AUTOMATICALLY GENERATED BY CARGO
+#
+# When uploading crates to the registry Cargo will automatically
+# "normalize" Cargo.toml files for maximal compatibility
+# with all versions of Cargo and also rewrite `path` dependencies
+# to registry (e.g., crates.io) dependencies.
+#
+# If you are reading this file be aware that the original Cargo.toml
+# will likely look very different (and much more reasonable).
+# See Cargo.toml.orig for the original contents.
+
+[package]
+name = "pkg-config"
+version = "0.3.26"
+authors = ["Alex Crichton <alex@alexcrichton.com>"]
+description = """
+A library to run the pkg-config system tool at build time in order to be used in
+Cargo build scripts.
+"""
+documentation = "https://docs.rs/pkg-config"
+readme = "README.md"
+keywords = ["build-dependencies"]
+license = "MIT OR Apache-2.0"
+repository = "https://github.com/rust-lang/pkg-config-rs"
+
+[dev-dependencies.lazy_static]
+version = "1"
diff --git a/third_party/rust/pkg-config/LICENSE-APACHE b/third_party/rust/pkg-config/LICENSE-APACHE
new file mode 100644
index 0000000000..16fe87b06e
--- /dev/null
+++ b/third_party/rust/pkg-config/LICENSE-APACHE
@@ -0,0 +1,201 @@
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+Copyright [yyyy] [name of copyright owner]
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+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
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+Unless required by applicable law or agreed to in writing, software
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diff --git a/third_party/rust/pkg-config/LICENSE-MIT b/third_party/rust/pkg-config/LICENSE-MIT
new file mode 100644
index 0000000000..39e0ed6602
--- /dev/null
+++ b/third_party/rust/pkg-config/LICENSE-MIT
@@ -0,0 +1,25 @@
+Copyright (c) 2014 Alex Crichton
+
+Permission is hereby granted, free of charge, to any
+person obtaining a copy of this software and associated
+documentation files (the "Software"), to deal in the
+Software without restriction, including without
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+publish, distribute, sublicense, and/or sell copies of
+the Software, and to permit persons to whom the Software
+is furnished to do so, subject to the following
+conditions:
+
+The above copyright notice and this permission notice
+shall be included in all copies or substantial portions
+of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF
+ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED
+TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
+PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT
+SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
+CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR
+IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+DEALINGS IN THE SOFTWARE.
diff --git a/third_party/rust/pkg-config/README.md b/third_party/rust/pkg-config/README.md
new file mode 100644
index 0000000000..61f1244c8d
--- /dev/null
+++ b/third_party/rust/pkg-config/README.md
@@ -0,0 +1,79 @@
+# pkg-config-rs
+
+[![Build Status](https://github.com/rust-lang/pkg-config-rs/actions/workflows/ci.yml/badge.svg)](https://github.com/rust-lang/pkg-config-rs/actions)
+[![Rust](https://img.shields.io/badge/rust-1.30%2B-blue.svg?maxAge=3600)](https://github.com/rust-lang/pkg-config-rs/)
+
+[Documentation](https://docs.rs/pkg-config)
+
+A simple library meant to be used as a build dependency with Cargo packages in
+order to use the system `pkg-config` tool (if available) to determine where a
+library is located.
+
+You can use this crate directly to probe for specific libraries, or use
+[system-deps](https://github.com/gdesmott/system-deps) to declare all your
+`pkg-config` dependencies in `Cargo.toml`.
+
+This library requires Rust 1.30+.
+
+# Example
+
+Find the system library named `foo`, with minimum version 1.2.3:
+
+```rust
+extern crate pkg_config;
+
+fn main() {
+    pkg_config::Config::new().atleast_version("1.2.3").probe("foo").unwrap();
+}
+```
+
+Find the system library named `foo`, with no version requirement (not
+recommended):
+
+```rust
+extern crate pkg_config;
+
+fn main() {
+    pkg_config::probe_library("foo").unwrap();
+}
+```
+
+# External configuration via target-scoped environment variables
+
+In cross-compilation context, it is useful to manage separately `PKG_CONFIG_PATH`
+and a few other variables for the `host` and the `target` platform.
+
+The supported variables are: `PKG_CONFIG_PATH`, `PKG_CONFIG_LIBDIR`, and
+`PKG_CONFIG_SYSROOT_DIR`.
+
+Each of these variables can also be supplied with certain prefixes and suffixes, in the following prioritized order:
+
+1. `<var>_<target>` - for example, `PKG_CONFIG_PATH_x86_64-unknown-linux-gnu`
+2. `<var>_<target_with_underscores>` - for example, `PKG_CONFIG_PATH_x86_64_unknown_linux_gnu`
+3. `<build-kind>_<var>` - for example, `HOST_PKG_CONFIG_PATH` or `TARGET_PKG_CONFIG_PATH`
+4. `<var>` - a plain `PKG_CONFIG_PATH`
+
+This crate will allow `pkg-config` to be used in cross-compilation
+if `PKG_CONFIG_SYSROOT_DIR` or `PKG_CONFIG` is set. You can set `PKG_CONFIG_ALLOW_CROSS=1`
+to bypass the compatibility check, but please note that enabling use of `pkg-config` in
+cross-compilation without appropriate sysroot and search paths set is likely to break builds.
+
+Some Rust sys crates support building vendored libraries from source, which may be a work
+around for lack of cross-compilation support in `pkg-config`.
+
+# License
+
+This project is licensed under either of
+
+ * Apache License, Version 2.0, ([LICENSE-APACHE](LICENSE-APACHE) or
+   https://www.apache.org/licenses/LICENSE-2.0)
+ * MIT license ([LICENSE-MIT](LICENSE-MIT) or
+   https://opensource.org/licenses/MIT)
+
+at your option.
+
+### Contribution
+
+Unless you explicitly state otherwise, any contribution intentionally submitted
+for inclusion in pkg-config-rs by you, as defined in the Apache-2.0 license, shall be
+dual licensed as above, without any additional terms or conditions.
diff --git a/third_party/rust/pkg-config/src/lib.rs b/third_party/rust/pkg-config/src/lib.rs
new file mode 100644
index 0000000000..e9395be465
--- /dev/null
+++ b/third_party/rust/pkg-config/src/lib.rs
@@ -0,0 +1,972 @@
+//! A build dependency for Cargo libraries to find system artifacts through the
+//! `pkg-config` utility.
+//!
+//! This library will shell out to `pkg-config` as part of build scripts and
+//! probe the system to determine how to link to a specified library. The
+//! `Config` structure serves as a method of configuring how `pkg-config` is
+//! invoked in a builder style.
+//!
+//! A number of environment variables are available to globally configure how
+//! this crate will invoke `pkg-config`:
+//!
+//! * `FOO_NO_PKG_CONFIG` - if set, this will disable running `pkg-config` when
+//!   probing for the library named `foo`.
+//!
+//! * `PKG_CONFIG_ALLOW_CROSS` - The `pkg-config` command usually doesn't
+//!   support cross-compilation, and this crate prevents it from selecting
+//!   incompatible versions of libraries.
+//!   Setting `PKG_CONFIG_ALLOW_CROSS=1` disables this protection, which is
+//!   likely to cause linking errors, unless `pkg-config` has been configured
+//!   to use appropriate sysroot and search paths for the target platform.
+//!
+//! There are also a number of environment variables which can configure how a
+//! library is linked to (dynamically vs statically). These variables control
+//! whether the `--static` flag is passed. Note that this behavior can be
+//! overridden by configuring explicitly on `Config`. The variables are checked
+//! in the following order:
+//!
+//! * `FOO_STATIC` - pass `--static` for the library `foo`
+//! * `FOO_DYNAMIC` - do not pass `--static` for the library `foo`
+//! * `PKG_CONFIG_ALL_STATIC` - pass `--static` for all libraries
+//! * `PKG_CONFIG_ALL_DYNAMIC` - do not pass `--static` for all libraries
+//!
+//! After running `pkg-config` all appropriate Cargo metadata will be printed on
+//! stdout if the search was successful.
+//!
+//! # Example
+//!
+//! Find the system library named `foo`, with minimum version 1.2.3:
+//!
+//! ```no_run
+//! fn main() {
+//!     pkg_config::Config::new().atleast_version("1.2.3").probe("foo").unwrap();
+//! }
+//! ```
+//!
+//! Find the system library named `foo`, with no version requirement (not
+//! recommended):
+//!
+//! ```no_run
+//! fn main() {
+//!     pkg_config::probe_library("foo").unwrap();
+//! }
+//! ```
+//!
+//! Configure how library `foo` is linked to.
+//!
+//! ```no_run
+//! fn main() {
+//!     pkg_config::Config::new().atleast_version("1.2.3").statik(true).probe("foo").unwrap();
+//! }
+//! ```
+
+#![doc(html_root_url = "https://docs.rs/pkg-config/0.3")]
+
+use std::collections::HashMap;
+use std::env;
+use std::error;
+use std::ffi::{OsStr, OsString};
+use std::fmt;
+use std::io;
+use std::ops::{Bound, RangeBounds};
+use std::path::PathBuf;
+use std::process::{Command, Output};
+use std::str;
+
+#[derive(Clone, Debug)]
+pub struct Config {
+    statik: Option<bool>,
+    min_version: Bound<String>,
+    max_version: Bound<String>,
+    extra_args: Vec<OsString>,
+    cargo_metadata: bool,
+    env_metadata: bool,
+    print_system_libs: bool,
+    print_system_cflags: bool,
+}
+
+#[derive(Clone, Debug)]
+pub struct Library {
+    /// Libraries specified by -l
+    pub libs: Vec<String>,
+    /// Library search paths specified by -L
+    pub link_paths: Vec<PathBuf>,
+    /// Library file paths specified without -l
+    pub link_files: Vec<PathBuf>,
+    /// Darwin frameworks specified by -framework
+    pub frameworks: Vec<String>,
+    /// Darwin framework search paths specified by -F
+    pub framework_paths: Vec<PathBuf>,
+    /// C/C++ header include paths specified by -I
+    pub include_paths: Vec<PathBuf>,
+    /// Linker options specified by -Wl
+    pub ld_args: Vec<Vec<String>>,
+    /// C/C++ definitions specified by -D
+    pub defines: HashMap<String, Option<String>>,
+    /// Version specified by .pc file's Version field
+    pub version: String,
+    /// Ensure that this struct can only be created via its private `[Library::new]` constructor.
+    /// Users of this crate can only access the struct via `[Config::probe]`.
+    _priv: (),
+}
+
+/// Represents all reasons `pkg-config` might not succeed or be run at all.
+pub enum Error {
+    /// Aborted because of `*_NO_PKG_CONFIG` environment variable.
+    ///
+    /// Contains the name of the responsible environment variable.
+    EnvNoPkgConfig(String),
+
+    /// Detected cross compilation without a custom sysroot.
+    ///
+    /// Ignore the error with `PKG_CONFIG_ALLOW_CROSS=1`,
+    /// which may let `pkg-config` select libraries
+    /// for the host's architecture instead of the target's.
+    CrossCompilation,
+
+    /// Failed to run `pkg-config`.
+    ///
+    /// Contains the command and the cause.
+    Command { command: String, cause: io::Error },
+
+    /// `pkg-config` did not exit sucessfully after probing a library.
+    ///
+    /// Contains the command and output.
+    Failure { command: String, output: Output },
+
+    /// `pkg-config` did not exit sucessfully on the first attempt to probe a library.
+    ///
+    /// Contains the command and output.
+    ProbeFailure {
+        name: String,
+        command: String,
+        output: Output,
+    },
+
+    #[doc(hidden)]
+    // please don't match on this, we're likely to add more variants over time
+    __Nonexhaustive,
+}
+
+impl error::Error for Error {}
+
+impl fmt::Debug for Error {
+    fn fmt(&self, f: &mut fmt::Formatter) -> Result<(), fmt::Error> {
+        // Failed `unwrap()` prints Debug representation, but the default debug format lacks helpful instructions for the end users
+        <Error as fmt::Display>::fmt(self, f)
+    }
+}
+
+impl fmt::Display for Error {
+    fn fmt(&self, f: &mut fmt::Formatter) -> Result<(), fmt::Error> {
+        match *self {
+            Error::EnvNoPkgConfig(ref name) => write!(f, "Aborted because {} is set", name),
+            Error::CrossCompilation => f.write_str(
+                "pkg-config has not been configured to support cross-compilation.\n\
+                \n\
+                Install a sysroot for the target platform and configure it via\n\
+                PKG_CONFIG_SYSROOT_DIR and PKG_CONFIG_PATH, or install a\n\
+                cross-compiling wrapper for pkg-config and set it via\n\
+                PKG_CONFIG environment variable.",
+            ),
+            Error::Command {
+                ref command,
+                ref cause,
+            } => {
+                match cause.kind() {
+                    io::ErrorKind::NotFound => {
+                        let crate_name =
+                            std::env::var("CARGO_PKG_NAME").unwrap_or_else(|_| "sys".to_owned());
+                        let instructions = if cfg!(target_os = "macos") || cfg!(target_os = "ios") {
+                            "Try `brew install pkg-config` if you have Homebrew.\n"
+                        } else if cfg!(unix) {
+                            "Try `apt install pkg-config`, or `yum install pkg-config`,\n\
+                            or `pkg install pkg-config`, or `apk add pkgconfig` \
+                            depending on your distribution.\n"
+                        } else {
+                            "" // There's no easy fix for Windows users
+                        };
+                        write!(f, "Could not run `{command}`\n\
+                        The pkg-config command could not be found.\n\
+                        \n\
+                        Most likely, you need to install a pkg-config package for your OS.\n\
+                        {instructions}\
+                        \n\
+                        If you've already installed it, ensure the pkg-config command is one of the\n\
+                        directories in the PATH environment variable.\n\
+                        \n\
+                        If you did not expect this build to link to a pre-installed system library,\n\
+                        then check documentation of the {crate_name} crate for an option to\n\
+                        build the library from source, or disable features or dependencies\n\
+                        that require pkg-config.", command = command, instructions = instructions, crate_name = crate_name)
+                    }
+                    _ => write!(f, "Failed to run command `{}`, because: {}", command, cause),
+                }
+            }
+            Error::ProbeFailure {
+                ref name,
+                ref command,
+                ref output,
+            } => {
+                write!(
+                    f,
+                    "`{}` did not exit successfully: {}\nerror: could not find system library '{}' required by the '{}' crate\n",
+                    command, output.status, name, env::var("CARGO_PKG_NAME").unwrap_or_default(),
+                )?;
+                format_output(output, f)
+            }
+            Error::Failure {
+                ref command,
+                ref output,
+            } => {
+                write!(
+                    f,
+                    "`{}` did not exit successfully: {}",
+                    command, output.status
+                )?;
+                format_output(output, f)
+            }
+            Error::__Nonexhaustive => panic!(),
+        }
+    }
+}
+
+fn format_output(output: &Output, f: &mut fmt::Formatter) -> fmt::Result {
+    let stdout = String::from_utf8_lossy(&output.stdout);
+    if !stdout.is_empty() {
+        write!(f, "\n--- stdout\n{}", stdout)?;
+    }
+    let stderr = String::from_utf8_lossy(&output.stderr);
+    if !stderr.is_empty() {
+        write!(f, "\n--- stderr\n{}", stderr)?;
+    }
+    Ok(())
+}
+
+/// Deprecated in favor of the probe_library function
+#[doc(hidden)]
+pub fn find_library(name: &str) -> Result<Library, String> {
+    probe_library(name).map_err(|e| e.to_string())
+}
+
+/// Simple shortcut for using all default options for finding a library.
+pub fn probe_library(name: &str) -> Result<Library, Error> {
+    Config::new().probe(name)
+}
+
+#[doc(hidden)]
+#[deprecated(note = "use config.target_supported() instance method instead")]
+pub fn target_supported() -> bool {
+    Config::new().target_supported()
+}
+
+/// Run `pkg-config` to get the value of a variable from a package using
+/// `--variable`.
+///
+/// The content of `PKG_CONFIG_SYSROOT_DIR` is not injected in paths that are
+/// returned by `pkg-config --variable`, which makes them unsuitable to use
+/// during cross-compilation unless specifically designed to be used
+/// at that time.
+pub fn get_variable(package: &str, variable: &str) -> Result<String, Error> {
+    let arg = format!("--variable={}", variable);
+    let cfg = Config::new();
+    let out = run(cfg.command(package, &[&arg]))?;
+    Ok(str::from_utf8(&out).unwrap().trim_end().to_owned())
+}
+
+impl Config {
+    /// Creates a new set of configuration options which are all initially set
+    /// to "blank".
+    pub fn new() -> Config {
+        Config {
+            statik: None,
+            min_version: Bound::Unbounded,
+            max_version: Bound::Unbounded,
+            extra_args: vec![],
+            print_system_cflags: true,
+            print_system_libs: true,
+            cargo_metadata: true,
+            env_metadata: true,
+        }
+    }
+
+    /// Indicate whether the `--static` flag should be passed.
+    ///
+    /// This will override the inference from environment variables described in
+    /// the crate documentation.
+    pub fn statik(&mut self, statik: bool) -> &mut Config {
+        self.statik = Some(statik);
+        self
+    }
+
+    /// Indicate that the library must be at least version `vers`.
+    pub fn atleast_version(&mut self, vers: &str) -> &mut Config {
+        self.min_version = Bound::Included(vers.to_string());
+        self.max_version = Bound::Unbounded;
+        self
+    }
+
+    /// Indicate that the library must be equal to version `vers`.
+    pub fn exactly_version(&mut self, vers: &str) -> &mut Config {
+        self.min_version = Bound::Included(vers.to_string());
+        self.max_version = Bound::Included(vers.to_string());
+        self
+    }
+
+    /// Indicate that the library's version must be in `range`.
+    pub fn range_version<'a, R>(&mut self, range: R) -> &mut Config
+    where
+        R: RangeBounds<&'a str>,
+    {
+        self.min_version = match range.start_bound() {
+            Bound::Included(vers) => Bound::Included(vers.to_string()),
+            Bound::Excluded(vers) => Bound::Excluded(vers.to_string()),
+            Bound::Unbounded => Bound::Unbounded,
+        };
+        self.max_version = match range.end_bound() {
+            Bound::Included(vers) => Bound::Included(vers.to_string()),
+            Bound::Excluded(vers) => Bound::Excluded(vers.to_string()),
+            Bound::Unbounded => Bound::Unbounded,
+        };
+        self
+    }
+
+    /// Add an argument to pass to pkg-config.
+    ///
+    /// It's placed after all of the arguments generated by this library.
+    pub fn arg<S: AsRef<OsStr>>(&mut self, arg: S) -> &mut Config {
+        self.extra_args.push(arg.as_ref().to_os_string());
+        self
+    }
+
+    /// Define whether metadata should be emitted for cargo allowing it to
+    /// automatically link the binary. Defaults to `true`.
+    pub fn cargo_metadata(&mut self, cargo_metadata: bool) -> &mut Config {
+        self.cargo_metadata = cargo_metadata;
+        self
+    }
+
+    /// Define whether metadata should be emitted for cargo allowing to
+    /// automatically rebuild when environment variables change. Defaults to
+    /// `true`.
+    pub fn env_metadata(&mut self, env_metadata: bool) -> &mut Config {
+        self.env_metadata = env_metadata;
+        self
+    }
+
+    /// Enable or disable the `PKG_CONFIG_ALLOW_SYSTEM_LIBS` environment
+    /// variable.
+    ///
+    /// This env var is enabled by default.
+    pub fn print_system_libs(&mut self, print: bool) -> &mut Config {
+        self.print_system_libs = print;
+        self
+    }
+
+    /// Enable or disable the `PKG_CONFIG_ALLOW_SYSTEM_CFLAGS` environment
+    /// variable.
+    ///
+    /// This env var is enabled by default.
+    pub fn print_system_cflags(&mut self, print: bool) -> &mut Config {
+        self.print_system_cflags = print;
+        self
+    }
+
+    /// Deprecated in favor fo the `probe` function
+    #[doc(hidden)]
+    pub fn find(&self, name: &str) -> Result<Library, String> {
+        self.probe(name).map_err(|e| e.to_string())
+    }
+
+    /// Run `pkg-config` to find the library `name`.
+    ///
+    /// This will use all configuration previously set to specify how
+    /// `pkg-config` is run.
+    pub fn probe(&self, name: &str) -> Result<Library, Error> {
+        let abort_var_name = format!("{}_NO_PKG_CONFIG", envify(name));
+        if self.env_var_os(&abort_var_name).is_some() {
+            return Err(Error::EnvNoPkgConfig(abort_var_name));
+        } else if !self.target_supported() {
+            return Err(Error::CrossCompilation);
+        }
+
+        let mut library = Library::new();
+
+        let output = run(self.command(name, &["--libs", "--cflags"])).map_err(|e| match e {
+            Error::Failure { command, output } => Error::ProbeFailure {
+                name: name.to_owned(),
+                command,
+                output,
+            },
+            other => other,
+        })?;
+        library.parse_libs_cflags(name, &output, self);
+
+        let output = run(self.command(name, &["--modversion"]))?;
+        library.parse_modversion(str::from_utf8(&output).unwrap());
+
+        Ok(library)
+    }
+
+    /// True if pkg-config is used for the host system, or configured for cross-compilation
+    pub fn target_supported(&self) -> bool {
+        let target = env::var_os("TARGET").unwrap_or_default();
+        let host = env::var_os("HOST").unwrap_or_default();
+
+        // Only use pkg-config in host == target situations by default (allowing an
+        // override).
+        if host == target {
+            return true;
+        }
+
+        // pkg-config may not be aware of cross-compilation, and require
+        // a wrapper script that sets up platform-specific prefixes.
+        match self.targetted_env_var("PKG_CONFIG_ALLOW_CROSS") {
+            // don't use pkg-config if explicitly disabled
+            Some(ref val) if val == "0" => false,
+            Some(_) => true,
+            None => {
+                // if not disabled, and pkg-config is customized,
+                // then assume it's prepared for cross-compilation
+                self.targetted_env_var("PKG_CONFIG").is_some()
+                    || self.targetted_env_var("PKG_CONFIG_SYSROOT_DIR").is_some()
+            }
+        }
+    }
+
+    /// Deprecated in favor of the top level `get_variable` function
+    #[doc(hidden)]
+    pub fn get_variable(package: &str, variable: &str) -> Result<String, String> {
+        get_variable(package, variable).map_err(|e| e.to_string())
+    }
+
+    fn targetted_env_var(&self, var_base: &str) -> Option<OsString> {
+        match (env::var("TARGET"), env::var("HOST")) {
+            (Ok(target), Ok(host)) => {
+                let kind = if host == target { "HOST" } else { "TARGET" };
+                let target_u = target.replace("-", "_");
+
+                self.env_var_os(&format!("{}_{}", var_base, target))
+                    .or_else(|| self.env_var_os(&format!("{}_{}", var_base, target_u)))
+                    .or_else(|| self.env_var_os(&format!("{}_{}", kind, var_base)))
+                    .or_else(|| self.env_var_os(var_base))
+            }
+            (Err(env::VarError::NotPresent), _) | (_, Err(env::VarError::NotPresent)) => {
+                self.env_var_os(var_base)
+            }
+            (Err(env::VarError::NotUnicode(s)), _) | (_, Err(env::VarError::NotUnicode(s))) => {
+                panic!(
+                    "HOST or TARGET environment variable is not valid unicode: {:?}",
+                    s
+                )
+            }
+        }
+    }
+
+    fn env_var_os(&self, name: &str) -> Option<OsString> {
+        if self.env_metadata {
+            println!("cargo:rerun-if-env-changed={}", name);
+        }
+        env::var_os(name)
+    }
+
+    fn is_static(&self, name: &str) -> bool {
+        self.statik.unwrap_or_else(|| self.infer_static(name))
+    }
+
+    fn command(&self, name: &str, args: &[&str]) -> Command {
+        let exe = self
+            .targetted_env_var("PKG_CONFIG")
+            .unwrap_or_else(|| OsString::from("pkg-config"));
+        let mut cmd = Command::new(exe);
+        if self.is_static(name) {
+            cmd.arg("--static");
+        }
+        cmd.args(args).args(&self.extra_args);
+
+        if let Some(value) = self.targetted_env_var("PKG_CONFIG_PATH") {
+            cmd.env("PKG_CONFIG_PATH", value);
+        }
+        if let Some(value) = self.targetted_env_var("PKG_CONFIG_LIBDIR") {
+            cmd.env("PKG_CONFIG_LIBDIR", value);
+        }
+        if let Some(value) = self.targetted_env_var("PKG_CONFIG_SYSROOT_DIR") {
+            cmd.env("PKG_CONFIG_SYSROOT_DIR", value);
+        }
+        if self.print_system_libs {
+            cmd.env("PKG_CONFIG_ALLOW_SYSTEM_LIBS", "1");
+        }
+        if self.print_system_cflags {
+            cmd.env("PKG_CONFIG_ALLOW_SYSTEM_CFLAGS", "1");
+        }
+        cmd.arg(name);
+        match self.min_version {
+            Bound::Included(ref version) => {
+                cmd.arg(&format!("{} >= {}", name, version));
+            }
+            Bound::Excluded(ref version) => {
+                cmd.arg(&format!("{} > {}", name, version));
+            }
+            _ => (),
+        }
+        match self.max_version {
+            Bound::Included(ref version) => {
+                cmd.arg(&format!("{} <= {}", name, version));
+            }
+            Bound::Excluded(ref version) => {
+                cmd.arg(&format!("{} < {}", name, version));
+            }
+            _ => (),
+        }
+        cmd
+    }
+
+    fn print_metadata(&self, s: &str) {
+        if self.cargo_metadata {
+            println!("cargo:{}", s);
+        }
+    }
+
+    fn infer_static(&self, name: &str) -> bool {
+        let name = envify(name);
+        if self.env_var_os(&format!("{}_STATIC", name)).is_some() {
+            true
+        } else if self.env_var_os(&format!("{}_DYNAMIC", name)).is_some() {
+            false
+        } else if self.env_var_os("PKG_CONFIG_ALL_STATIC").is_some() {
+            true
+        } else if self.env_var_os("PKG_CONFIG_ALL_DYNAMIC").is_some() {
+            false
+        } else {
+            false
+        }
+    }
+}
+
+// Implement Default manualy since Bound does not implement Default.
+impl Default for Config {
+    fn default() -> Config {
+        Config {
+            statik: None,
+            min_version: Bound::Unbounded,
+            max_version: Bound::Unbounded,
+            extra_args: vec![],
+            print_system_cflags: false,
+            print_system_libs: false,
+            cargo_metadata: false,
+            env_metadata: false,
+        }
+    }
+}
+
+impl Library {
+    fn new() -> Library {
+        Library {
+            libs: Vec::new(),
+            link_paths: Vec::new(),
+            link_files: Vec::new(),
+            include_paths: Vec::new(),
+            ld_args: Vec::new(),
+            frameworks: Vec::new(),
+            framework_paths: Vec::new(),
+            defines: HashMap::new(),
+            version: String::new(),
+            _priv: (),
+        }
+    }
+
+    /// Extract the &str to pass to cargo:rustc-link-lib from a filename (just the file name, not including directories)
+    /// using target-specific logic.
+    fn extract_lib_from_filename<'a>(target: &str, filename: &'a str) -> Option<&'a str> {
+        fn test_suffixes<'b>(filename: &'b str, suffixes: &[&str]) -> Option<&'b str> {
+            for suffix in suffixes {
+                if filename.ends_with(suffix) {
+                    return Some(&filename[..filename.len() - suffix.len()]);
+                }
+            }
+            None
+        }
+
+        let prefix = "lib";
+        if target.contains("msvc") {
+            // According to link.exe documentation:
+            // https://learn.microsoft.com/en-us/cpp/build/reference/link-input-files?view=msvc-170
+            //
+            //   LINK doesn't use file extensions to make assumptions about the contents of a file.
+            //   Instead, LINK examines each input file to determine what kind of file it is.
+            //
+            // However, rustc appends `.lib` to the string it receives from the -l command line argument,
+            // which it receives from Cargo via cargo:rustc-link-lib:
+            // https://github.com/rust-lang/rust/blob/657f246812ab2684e3c3954b1c77f98fd59e0b21/compiler/rustc_codegen_ssa/src/back/linker.rs#L828
+            // https://github.com/rust-lang/rust/blob/657f246812ab2684e3c3954b1c77f98fd59e0b21/compiler/rustc_codegen_ssa/src/back/linker.rs#L843
+            // So the only file extension that works for MSVC targets is `.lib`
+            return test_suffixes(filename, &[".lib"]);
+        } else if target.contains("windows") && target.contains("gnu") {
+            // GNU targets for Windows, including gnullvm, use `LinkerFlavor::Gcc` internally in rustc,
+            // which tells rustc to use the GNU linker. rustc does not prepend/append to the string it
+            // receives via the -l command line argument before passing it to the linker:
+            // https://github.com/rust-lang/rust/blob/657f246812ab2684e3c3954b1c77f98fd59e0b21/compiler/rustc_codegen_ssa/src/back/linker.rs#L446
+            // https://github.com/rust-lang/rust/blob/657f246812ab2684e3c3954b1c77f98fd59e0b21/compiler/rustc_codegen_ssa/src/back/linker.rs#L457
+            // GNU ld can work with more types of files than just the .lib files that MSVC's link.exe needs.
+            // GNU ld will prepend the `lib` prefix to the filename if necessary, so it is okay to remove
+            // the `lib` prefix from the filename. The `.a` suffix *requires* the `lib` prefix.
+            // https://sourceware.org/binutils/docs-2.39/ld.html#index-direct-linking-to-a-dll
+            if filename.starts_with(prefix) {
+                let filename = &filename[prefix.len()..];
+                return test_suffixes(filename, &[".dll.a", ".dll", ".lib", ".a"]);
+            } else {
+                return test_suffixes(filename, &[".dll.a", ".dll", ".lib"]);
+            }
+        } else if target.contains("apple") {
+            if filename.starts_with(prefix) {
+                let filename = &filename[prefix.len()..];
+                return test_suffixes(filename, &[".a", ".so", ".dylib"]);
+            }
+            return None;
+        } else {
+            if filename.starts_with(prefix) {
+                let filename = &filename[prefix.len()..];
+                return test_suffixes(filename, &[".a", ".so"]);
+            }
+            return None;
+        }
+    }
+
+    fn parse_libs_cflags(&mut self, name: &str, output: &[u8], config: &Config) {
+        let mut is_msvc = false;
+        let target = env::var("TARGET");
+        if let Ok(target) = &target {
+            if target.contains("msvc") {
+                is_msvc = true;
+            }
+        }
+
+        let system_roots = if cfg!(target_os = "macos") {
+            vec![PathBuf::from("/Library"), PathBuf::from("/System")]
+        } else {
+            let sysroot = config
+                .env_var_os("PKG_CONFIG_SYSROOT_DIR")
+                .or_else(|| config.env_var_os("SYSROOT"))
+                .map(PathBuf::from);
+
+            if cfg!(target_os = "windows") {
+                if let Some(sysroot) = sysroot {
+                    vec![sysroot]
+                } else {
+                    vec![]
+                }
+            } else {
+                vec![sysroot.unwrap_or_else(|| PathBuf::from("/usr"))]
+            }
+        };
+
+        let mut dirs = Vec::new();
+        let statik = config.is_static(name);
+
+        let words = split_flags(output);
+
+        // Handle single-character arguments like `-I/usr/include`
+        let parts = words
+            .iter()
+            .filter(|l| l.len() > 2)
+            .map(|arg| (&arg[0..2], &arg[2..]));
+        for (flag, val) in parts {
+            match flag {
+                "-L" => {
+                    let meta = format!("rustc-link-search=native={}", val);
+                    config.print_metadata(&meta);
+                    dirs.push(PathBuf::from(val));
+                    self.link_paths.push(PathBuf::from(val));
+                }
+                "-F" => {
+                    let meta = format!("rustc-link-search=framework={}", val);
+                    config.print_metadata(&meta);
+                    self.framework_paths.push(PathBuf::from(val));
+                }
+                "-I" => {
+                    self.include_paths.push(PathBuf::from(val));
+                }
+                "-l" => {
+                    // These are provided by the CRT with MSVC
+                    if is_msvc && ["m", "c", "pthread"].contains(&val) {
+                        continue;
+                    }
+
+                    if statik && is_static_available(val, &system_roots, &dirs) {
+                        let meta = format!("rustc-link-lib=static={}", val);
+                        config.print_metadata(&meta);
+                    } else {
+                        let meta = format!("rustc-link-lib={}", val);
+                        config.print_metadata(&meta);
+                    }
+
+                    self.libs.push(val.to_string());
+                }
+                "-D" => {
+                    let mut iter = val.split('=');
+                    self.defines.insert(
+                        iter.next().unwrap().to_owned(),
+                        iter.next().map(|s| s.to_owned()),
+                    );
+                }
+                _ => {}
+            }
+        }
+
+        // Handle multi-character arguments with space-separated value like `-framework foo`
+        let mut iter = words.iter().flat_map(|arg| {
+            if arg.starts_with("-Wl,") {
+                arg[4..].split(',').collect()
+            } else {
+                vec![arg.as_ref()]
+            }
+        });
+        while let Some(part) = iter.next() {
+            match part {
+                "-framework" => {
+                    if let Some(lib) = iter.next() {
+                        let meta = format!("rustc-link-lib=framework={}", lib);
+                        config.print_metadata(&meta);
+                        self.frameworks.push(lib.to_string());
+                    }
+                }
+                "-isystem" | "-iquote" | "-idirafter" => {
+                    if let Some(inc) = iter.next() {
+                        self.include_paths.push(PathBuf::from(inc));
+                    }
+                }
+                _ => {
+                    let path = std::path::Path::new(part);
+                    if path.is_file() {
+                        // Cargo doesn't have a means to directly specify a file path to link,
+                        // so split up the path into the parent directory and library name.
+                        // TODO: pass file path directly when link-arg library type is stabilized
+                        // https://github.com/rust-lang/rust/issues/99427
+                        if let (Some(dir), Some(file_name), Ok(target)) =
+                            (path.parent(), path.file_name(), &target)
+                        {
+                            match Self::extract_lib_from_filename(
+                                target,
+                                &file_name.to_string_lossy(),
+                            ) {
+                                Some(lib_basename) => {
+                                    let link_search =
+                                        format!("rustc-link-search={}", dir.display());
+                                    config.print_metadata(&link_search);
+
+                                    let link_lib = format!("rustc-link-lib={}", lib_basename);
+                                    config.print_metadata(&link_lib);
+                                    self.link_files.push(PathBuf::from(path));
+                                }
+                                None => {
+                                    println!("cargo:warning=File path {} found in pkg-config file for {}, but could not extract library base name to pass to linker command line", path.display(), name);
+                                }
+                            }
+                        }
+                    }
+                }
+            }
+        }
+
+        let mut linker_options = words.iter().filter(|arg| arg.starts_with("-Wl,"));
+        while let Some(option) = linker_options.next() {
+            let mut pop = false;
+            let mut ld_option = vec![];
+            for subopt in option[4..].split(',') {
+                if pop {
+                    pop = false;
+                    continue;
+                }
+
+                if subopt == "-framework" {
+                    pop = true;
+                    continue;
+                }
+
+                ld_option.push(subopt);
+            }
+
+            let meta = format!("rustc-link-arg=-Wl,{}", ld_option.join(","));
+            config.print_metadata(&meta);
+
+            self.ld_args
+                .push(ld_option.into_iter().map(String::from).collect());
+        }
+    }
+
+    fn parse_modversion(&mut self, output: &str) {
+        self.version.push_str(output.lines().nth(0).unwrap().trim());
+    }
+}
+
+fn envify(name: &str) -> String {
+    name.chars()
+        .map(|c| c.to_ascii_uppercase())
+        .map(|c| if c == '-' { '_' } else { c })
+        .collect()
+}
+
+/// System libraries should only be linked dynamically
+fn is_static_available(name: &str, system_roots: &[PathBuf], dirs: &[PathBuf]) -> bool {
+    let libname = format!("lib{}.a", name);
+
+    dirs.iter().any(|dir| {
+        !system_roots.iter().any(|sys| dir.starts_with(sys)) && dir.join(&libname).exists()
+    })
+}
+
+fn run(mut cmd: Command) -> Result<Vec<u8>, Error> {
+    match cmd.output() {
+        Ok(output) => {
+            if output.status.success() {
+                Ok(output.stdout)
+            } else {
+                Err(Error::Failure {
+                    command: format!("{:?}", cmd),
+                    output,
+                })
+            }
+        }
+        Err(cause) => Err(Error::Command {
+            command: format!("{:?}", cmd),
+            cause,
+        }),
+    }
+}
+
+/// Split output produced by pkg-config --cflags and / or --libs into separate flags.
+///
+/// Backslash in output is used to preserve literal meaning of following byte.  Different words are
+/// separated by unescaped space. Other whitespace characters generally should not occur unescaped
+/// at all, apart from the newline at the end of output. For compatibility with what others
+/// consumers of pkg-config output would do in this scenario, they are used here for splitting as
+/// well.
+fn split_flags(output: &[u8]) -> Vec<String> {
+    let mut word = Vec::new();
+    let mut words = Vec::new();
+    let mut escaped = false;
+
+    for &b in output {
+        match b {
+            _ if escaped => {
+                escaped = false;
+                word.push(b);
+            }
+            b'\\' => escaped = true,
+            b'\t' | b'\n' | b'\r' | b' ' => {
+                if !word.is_empty() {
+                    words.push(String::from_utf8(word).unwrap());
+                    word = Vec::new();
+                }
+            }
+            _ => word.push(b),
+        }
+    }
+
+    if !word.is_empty() {
+        words.push(String::from_utf8(word).unwrap());
+    }
+
+    words
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    #[cfg(target_os = "macos")]
+    fn system_library_mac_test() {
+        use std::path::Path;
+
+        let system_roots = vec![PathBuf::from("/Library"), PathBuf::from("/System")];
+
+        assert!(!is_static_available(
+            "PluginManager",
+            &system_roots,
+            &[PathBuf::from("/Library/Frameworks")]
+        ));
+        assert!(!is_static_available(
+            "python2.7",
+            &system_roots,
+            &[PathBuf::from(
+                "/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/config"
+            )]
+        ));
+        assert!(!is_static_available(
+            "ffi_convenience",
+            &system_roots,
+            &[PathBuf::from(
+                "/Library/Ruby/Gems/2.0.0/gems/ffi-1.9.10/ext/ffi_c/libffi-x86_64/.libs"
+            )]
+        ));
+
+        // Homebrew is in /usr/local, and it's not a part of the OS
+        if Path::new("/usr/local/lib/libpng16.a").exists() {
+            assert!(is_static_available(
+                "png16",
+                &system_roots,
+                &[PathBuf::from("/usr/local/lib")]
+            ));
+
+            let libpng = Config::new()
+                .range_version("1".."99")
+                .probe("libpng16")
+                .unwrap();
+            assert!(libpng.version.find('\n').is_none());
+        }
+    }
+
+    #[test]
+    #[cfg(target_os = "linux")]
+    fn system_library_linux_test() {
+        assert!(!is_static_available(
+            "util",
+            &[PathBuf::from("/usr")],
+            &[PathBuf::from("/usr/lib/x86_64-linux-gnu")]
+        ));
+        assert!(!is_static_available(
+            "dialog",
+            &[PathBuf::from("/usr")],
+            &[PathBuf::from("/usr/lib")]
+        ));
+    }
+
+    fn test_library_filename(target: &str, filename: &str) {
+        assert_eq!(
+            Library::extract_lib_from_filename(target, filename),
+            Some("foo")
+        );
+    }
+
+    #[test]
+    fn link_filename_linux() {
+        let target = "x86_64-unknown-linux-gnu";
+        test_library_filename(target, "libfoo.a");
+        test_library_filename(target, "libfoo.so");
+    }
+
+    #[test]
+    fn link_filename_apple() {
+        let target = "x86_64-apple-darwin";
+        test_library_filename(target, "libfoo.a");
+        test_library_filename(target, "libfoo.so");
+        test_library_filename(target, "libfoo.dylib");
+    }
+
+    #[test]
+    fn link_filename_msvc() {
+        let target = "x86_64-pc-windows-msvc";
+        // static and dynamic libraries have the same .lib suffix
+        test_library_filename(target, "foo.lib");
+    }
+
+    #[test]
+    fn link_filename_mingw() {
+        let target = "x86_64-pc-windows-gnu";
+        test_library_filename(target, "foo.lib");
+        test_library_filename(target, "libfoo.a");
+        test_library_filename(target, "foo.dll");
+        test_library_filename(target, "foo.dll.a");
+    }
+}
diff --git a/third_party/rust/pkg-config/tests/escape.pc b/third_party/rust/pkg-config/tests/escape.pc
new file mode 100644
index 0000000000..701c4bf73f
--- /dev/null
+++ b/third_party/rust/pkg-config/tests/escape.pc
@@ -0,0 +1,5 @@
+Name: Escape
+Version: 4.2.0
+Description: Escape utility library
+Libs: -Llink\ path\ with\ spaces
+Cflags: -Iinclude\ path\ with\ spaces -DA=\"escaped\ string\'\ literal\" -DB=ESCAPED\ IDENTIFIER -DFOX=🦊
diff --git a/third_party/rust/pkg-config/tests/foo.pc b/third_party/rust/pkg-config/tests/foo.pc
new file mode 100644
index 0000000000..ce63ceb558
--- /dev/null
+++ b/third_party/rust/pkg-config/tests/foo.pc
@@ -0,0 +1,16 @@
+prefix=/usr
+exec_prefix=${prefix}
+libdir=${exec_prefix}/lib
+includedir=${prefix}/include/valgrind
+arch=amd64
+os=linux
+platform=amd64-linux
+valt_load_address=0x38000000
+
+Name: Valgrind
+Description: A dynamic binary instrumentation framework
+Version: 3.10.0.SVN
+Requires:
+Libs: -L${libdir}/valgrind -lcoregrind-amd64-linux -lvex-amd64-linux -lgcc
+Cflags: -I${includedir} -isystem /usr/foo
+
diff --git a/third_party/rust/pkg-config/tests/framework.pc b/third_party/rust/pkg-config/tests/framework.pc
new file mode 100644
index 0000000000..fec17f47a6
--- /dev/null
+++ b/third_party/rust/pkg-config/tests/framework.pc
@@ -0,0 +1,16 @@
+prefix=/usr
+exec_prefix=${prefix}
+libdir=${exec_prefix}/lib
+includedir=${prefix}/include/valgrind
+arch=amd64
+os=linux
+platform=amd64-linux
+valt_load_address=0x38000000
+
+Name: Valgrind
+Description: A dynamic binary instrumentation framework
+Version: 3.10.0.SVN
+Requires:
+Libs: -F${libdir} -framework foo -Wl,-framework,bar -Wl,-framework -Wl,baz -Wl,-framework,foobar,-framework,foobaz
+Cflags: -I${includedir}
+
diff --git a/third_party/rust/pkg-config/tests/rpath.pc b/third_party/rust/pkg-config/tests/rpath.pc
new file mode 100644
index 0000000000..7c36c5cb71
--- /dev/null
+++ b/third_party/rust/pkg-config/tests/rpath.pc
@@ -0,0 +1,7 @@
+prefix=/usr/local
+
+Name: rpath
+Version: 4.2.0
+Description: RPath example library
+Libs: -L${prefix}/lib -Wl,-rpath,${prefix}/lib -lrpath
+Cflags: -I${prefix}/include
diff --git a/third_party/rust/pkg-config/tests/test.rs b/third_party/rust/pkg-config/tests/test.rs
new file mode 100644
index 0000000000..4e04ac0712
--- /dev/null
+++ b/third_party/rust/pkg-config/tests/test.rs
@@ -0,0 +1,323 @@
+extern crate pkg_config;
+#[macro_use]
+extern crate lazy_static;
+
+use pkg_config::Error;
+use std::env;
+use std::path::PathBuf;
+use std::sync::Mutex;
+
+lazy_static! {
+    static ref LOCK: Mutex<()> = Mutex::new(());
+}
+
+fn reset() {
+    for (k, _) in env::vars() {
+        if k.contains("DYNAMIC")
+            || k.contains("STATIC")
+            || k.contains("PKG_CONFIG_ALLOW_CROSS")
+            || k.contains("PKG_CONFIG_SYSROOT_DIR")
+            || k.contains("FOO_NO_PKG_CONFIG")
+        {
+            env::remove_var(&k);
+        }
+    }
+    env::remove_var("TARGET");
+    env::remove_var("HOST");
+    env::set_var(
+        "PKG_CONFIG_PATH",
+        &env::current_dir().unwrap().join("tests"),
+    );
+}
+
+fn find(name: &str) -> Result<pkg_config::Library, Error> {
+    pkg_config::probe_library(name)
+}
+
+#[test]
+fn cross_disabled() {
+    let _g = LOCK.lock();
+    reset();
+    env::set_var("TARGET", "foo");
+    env::set_var("HOST", "bar");
+    match find("foo") {
+        Err(Error::CrossCompilation) => {}
+        x => panic!("Error::CrossCompilation expected, found `{:?}`", x),
+    }
+}
+
+#[test]
+fn cross_enabled() {
+    let _g = LOCK.lock();
+    reset();
+    env::set_var("TARGET", "foo");
+    env::set_var("HOST", "bar");
+    env::set_var("PKG_CONFIG_ALLOW_CROSS", "1");
+    find("foo").unwrap();
+}
+
+#[test]
+fn cross_enabled_if_customized() {
+    let _g = LOCK.lock();
+    reset();
+    env::set_var("TARGET", "foo");
+    env::set_var("HOST", "bar");
+    env::set_var("PKG_CONFIG_SYSROOT_DIR", "/tmp/cross-test");
+    find("foo").unwrap();
+}
+
+#[test]
+fn cross_disabled_if_customized() {
+    let _g = LOCK.lock();
+    reset();
+    env::set_var("TARGET", "foo");
+    env::set_var("HOST", "bar");
+    env::set_var("PKG_CONFIG_ALLOW_CROSS", "0");
+    env::set_var("PKG_CONFIG_SYSROOT_DIR", "/tmp/cross-test");
+    match find("foo") {
+        Err(Error::CrossCompilation) => {}
+        _ => panic!("expected CrossCompilation failure"),
+    }
+}
+
+#[test]
+fn package_disabled() {
+    let _g = LOCK.lock();
+    reset();
+    env::set_var("FOO_NO_PKG_CONFIG", "1");
+    match find("foo") {
+        Err(Error::EnvNoPkgConfig(name)) => assert_eq!(name, "FOO_NO_PKG_CONFIG"),
+        x => panic!("Error::EnvNoPkgConfig expected, found `{:?}`", x),
+    }
+}
+
+#[test]
+fn output_ok() {
+    let _g = LOCK.lock();
+    reset();
+    let lib = find("foo").unwrap();
+    assert!(lib.libs.contains(&"gcc".to_string()));
+    assert!(lib.libs.contains(&"coregrind-amd64-linux".to_string()));
+    assert!(lib.link_paths.contains(&PathBuf::from("/usr/lib/valgrind")));
+    assert!(lib
+        .include_paths
+        .contains(&PathBuf::from("/usr/include/valgrind")));
+    assert!(lib.include_paths.contains(&PathBuf::from("/usr/foo")));
+}
+
+#[test]
+fn escapes() {
+    let _g = LOCK.lock();
+    reset();
+    let lib = find("escape").unwrap();
+    assert!(lib
+        .include_paths
+        .contains(&PathBuf::from("include path with spaces")));
+    assert!(lib
+        .link_paths
+        .contains(&PathBuf::from("link path with spaces")));
+    assert_eq!(
+        lib.defines.get("A"),
+        Some(&Some("\"escaped string' literal\"".to_owned()))
+    );
+    assert_eq!(
+        lib.defines.get("B"),
+        Some(&Some("ESCAPED IDENTIFIER".to_owned()))
+    );
+    assert_eq!(lib.defines.get("FOX"), Some(&Some("🦊".to_owned())));
+}
+
+#[test]
+fn framework() {
+    let _g = LOCK.lock();
+    reset();
+    let lib = find("framework").unwrap();
+    assert!(lib.frameworks.contains(&"foo".to_string()));
+    assert!(lib.frameworks.contains(&"bar".to_string()));
+    assert!(lib.frameworks.contains(&"baz".to_string()));
+    assert!(lib.frameworks.contains(&"foobar".to_string()));
+    assert!(lib.frameworks.contains(&"foobaz".to_string()));
+    assert!(lib.framework_paths.contains(&PathBuf::from("/usr/lib")));
+}
+
+#[test]
+fn get_variable() {
+    let _g = LOCK.lock();
+    reset();
+    let prefix = pkg_config::get_variable("foo", "prefix").unwrap();
+    assert_eq!(prefix, "/usr");
+}
+
+#[test]
+fn version() {
+    let _g = LOCK.lock();
+    reset();
+    assert_eq!(&find("foo").unwrap().version[..], "3.10.0.SVN");
+}
+
+#[test]
+fn atleast_version_ok() {
+    let _g = LOCK.lock();
+    reset();
+    pkg_config::Config::new()
+        .atleast_version("3.10")
+        .probe("foo")
+        .unwrap();
+}
+
+#[test]
+#[should_panic]
+fn atleast_version_ng() {
+    let _g = LOCK.lock();
+    reset();
+    pkg_config::Config::new()
+        .atleast_version("3.11")
+        .probe("foo")
+        .unwrap();
+}
+
+#[test]
+fn exactly_version_ok() {
+    let _g = LOCK.lock();
+    reset();
+    pkg_config::Config::new()
+        .exactly_version("3.10.0.SVN")
+        .probe("foo")
+        .unwrap();
+}
+
+#[test]
+#[should_panic]
+fn exactly_version_ng() {
+    let _g = LOCK.lock();
+    reset();
+    pkg_config::Config::new()
+        .exactly_version("3.10.0")
+        .probe("foo")
+        .unwrap();
+}
+
+#[test]
+fn range_version_range_ok() {
+    let _g = LOCK.lock();
+    reset();
+    pkg_config::Config::new()
+        .range_version("4.2.0".."4.4.0")
+        .probe("escape")
+        .unwrap();
+}
+
+#[test]
+#[should_panic]
+fn range_version_range_ng() {
+    let _g = LOCK.lock();
+    reset();
+    pkg_config::Config::new()
+        .range_version("4.0.0".."4.2.0")
+        .probe("escape")
+        .unwrap();
+}
+
+#[test]
+fn range_version_range_inclusive_ok() {
+    let _g = LOCK.lock();
+    reset();
+    pkg_config::Config::new()
+        .range_version("4.0.0"..="4.2.0")
+        .probe("escape")
+        .unwrap();
+}
+
+#[test]
+#[should_panic]
+fn range_version_range_inclusive_ng() {
+    let _g = LOCK.lock();
+    reset();
+    pkg_config::Config::new()
+        .range_version("3.8.0"..="4.0.0")
+        .probe("escape")
+        .unwrap();
+}
+
+#[test]
+fn range_version_range_from_ok() {
+    let _g = LOCK.lock();
+    reset();
+    pkg_config::Config::new()
+        .range_version("4.0.0"..)
+        .probe("escape")
+        .unwrap();
+}
+
+#[test]
+#[should_panic]
+fn range_version_range_from_ng() {
+    let _g = LOCK.lock();
+    reset();
+    pkg_config::Config::new()
+        .range_version("4.4.0"..)
+        .probe("escape")
+        .unwrap();
+}
+
+#[test]
+fn range_version_range_to_ok() {
+    let _g = LOCK.lock();
+    reset();
+    pkg_config::Config::new()
+        .range_version(.."4.4.0")
+        .probe("escape")
+        .unwrap();
+}
+
+#[test]
+#[should_panic]
+fn range_version_range_to_ng() {
+    let _g = LOCK.lock();
+    reset();
+    pkg_config::Config::new()
+        .range_version(.."4.2.0")
+        .probe("escape")
+        .unwrap();
+}
+
+#[test]
+fn range_version_range_to_inclusive_ok() {
+    let _g = LOCK.lock();
+    reset();
+    pkg_config::Config::new()
+        .range_version(..="4.2.0")
+        .probe("escape")
+        .unwrap();
+}
+
+#[test]
+#[should_panic]
+fn range_version_range_to_inclusive_ng() {
+    let _g = LOCK.lock();
+    reset();
+    pkg_config::Config::new()
+        .range_version(..="4.0.0")
+        .probe("escape")
+        .unwrap();
+}
+
+#[test]
+fn range_version_full() {
+    let _g = LOCK.lock();
+    reset();
+    pkg_config::Config::new()
+        .range_version(..)
+        .probe("escape")
+        .unwrap();
+}
+
+#[test]
+fn rpath() {
+    let _g = LOCK.lock();
+    reset();
+    let lib = find("rpath").unwrap();
+    assert!(lib
+        .ld_args
+        .contains(&vec!["-rpath".to_string(), "/usr/local/lib".to_string(),]));
+}