Merging upstream version 1.70.0+dfsg2.

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

9 files changed, 687 insertions, 0 deletions

diff --git a/extra/git2-curl/.cargo-checksum.json b/extra/git2-curl/.cargo-checksum.json
new file mode 100644
index 000000000..3618c16b0
--- /dev/null
+++ b/extra/git2-curl/.cargo-checksum.json
@@ -0,0 +1 @@
+{"files":{},"package":"bef38d45163c2f1dde094a7dfd33ccf595c92905c8f8f4fdc18d06fb1037718a"}
\ No newline at end of file
diff --git a/extra/git2-curl/CHANGELOG.md b/extra/git2-curl/CHANGELOG.md
new file mode 100644
index 000000000..98867bc28
--- /dev/null
+++ b/extra/git2-curl/CHANGELOG.md
@@ -0,0 +1,26 @@
+# Changelog
+
+## 0.19.0 - 2023-08-28
+[0.18.0...0.19.0](https://github.com/rust-lang/git2-rs/compare/git2-curl-0.18.0...git2-curl-0.19.0)
+
+- Updated to [git2 0.18.0](../CHANGELOG.md#0180---2023-08-26)
+
+## 0.18.0 - 2023-04-02
+[0.17.0...0.18.0](https://github.com/rust-lang/git2-rs/compare/git2-curl-0.17.0...git2-curl-0.18.0)
+
+- Updated to [git2 0.17.0](../CHANGELOG.md#0170---2023-04-02)
+
+## 0.17.0 - 2023-01-10
+[0.16.0...0.17.0](https://github.com/rust-lang/git2-rs/compare/git2-curl-0.16.0...git2-curl-0.17.0)
+
+- Updated to [git2 0.16.0](../CHANGELOG.md#0160---2023-01-10)
+
+## 0.16.0 - 2022-07-28
+[0.15.0...0.16.0](https://github.com/rust-lang/git2-rs/compare/git2-curl-0.15.0...git2-curl-0.16.0)
+
+- Updated to [git2 0.15.0](../CHANGELOG.md#0150---2022-07-28)
+
+## 0.15.0 - 2022-02-28
+[0.14.1...0.15.0](https://github.com/rust-lang/git2-rs/compare/git2-curl-0.14.1...git2-curl-0.15.0)
+
+- Updated to [git2 0.14.0](../CHANGELOG.md#0140---2022-02-24)
diff --git a/extra/git2-curl/Cargo.toml b/extra/git2-curl/Cargo.toml
new file mode 100644
index 000000000..f4240e0e6
--- /dev/null
+++ b/extra/git2-curl/Cargo.toml
@@ -0,0 +1,58 @@
+# 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]
+edition = "2018"
+name = "git2-curl"
+version = "0.19.0"
+authors = [
+    "Josh Triplett <josh@joshtriplett.org>",
+    "Alex Crichton <alex@alexcrichton.com>",
+]
+description = """
+Backend for an HTTP transport in libgit2 powered by libcurl.
+
+Intended to be used with the git2 crate.
+"""
+documentation = "https://docs.rs/git2-curl"
+license = "MIT OR Apache-2.0"
+repository = "https://github.com/rust-lang/git2-rs"
+
+[[test]]
+name = "all"
+harness = false
+
+[dependencies.curl]
+version = "0.4.33"
+
+[dependencies.git2]
+version = "0.18"
+default-features = false
+
+[dependencies.log]
+version = "0.4"
+
+[dependencies.url]
+version = "2.0"
+
+[dev-dependencies.civet]
+version = "0.11"
+
+[dev-dependencies.conduit]
+version = "0.8"
+
+[dev-dependencies.conduit-git-http-backend]
+version = "0.8"
+
+[dev-dependencies.tempfile]
+version = "3.0"
+
+[features]
diff --git a/extra/git2-curl/LICENSE-APACHE b/extra/git2-curl/LICENSE-APACHE
new file mode 100644
index 000000000..16fe87b06
--- /dev/null
+++ b/extra/git2-curl/LICENSE-APACHE
@@ -0,0 +1,201 @@
+                              Apache License
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+TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
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+
+   To apply the Apache License to your work, attach the following
+   boilerplate notice, with the fields enclosed by brackets "[]"
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+   file or class name and description of purpose be included on the
+   same "printed page" as the copyright notice for easier
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+
+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
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diff --git a/extra/git2-curl/LICENSE-MIT b/extra/git2-curl/LICENSE-MIT
new file mode 100644
index 000000000..39e0ed660
--- /dev/null
+++ b/extra/git2-curl/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
+limitation the rights to use, copy, modify, merge,
+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/extra/git2-curl/debian/patches/remove-zlib-ng-compat.patch b/extra/git2-curl/debian/patches/remove-zlib-ng-compat.patch
new file mode 100644
index 000000000..48b215a4c
--- /dev/null
+++ b/extra/git2-curl/debian/patches/remove-zlib-ng-compat.patch
@@ -0,0 +1,10 @@
+--- a/Cargo.toml
++++ b/Cargo.toml
+@@ -56,7 +56,3 @@
+ version = "3.0"
+ 
+ [features]
+-zlib-ng-compat = [
+-    "git2/zlib-ng-compat",
+-    "curl/zlib-ng-compat",
+-]
diff --git a/extra/git2-curl/debian/patches/series b/extra/git2-curl/debian/patches/series
new file mode 100644
index 000000000..3ed6c2fdf
--- /dev/null
+++ b/extra/git2-curl/debian/patches/series
@@ -0,0 +1 @@
+remove-zlib-ng-compat.patch
diff --git a/extra/git2-curl/src/lib.rs b/extra/git2-curl/src/lib.rs
new file mode 100644
index 000000000..dbdbdc4a6
--- /dev/null
+++ b/extra/git2-curl/src/lib.rs
@@ -0,0 +1,291 @@
+//! A crate for using libcurl as a backend for HTTP git requests with git2-rs.
+//!
+//! This crate provides one public function, `register`, which will register
+//! a custom HTTP transport with libcurl for any HTTP requests made by libgit2.
+//! At this time the `register` function is unsafe for the same reasons that
+//! `git2::transport::register` is also unsafe.
+//!
+//! It is not recommended to use this crate wherever possible. The current
+//! libcurl backend used, `curl-rust`, only supports executing a request in one
+//! method call implying no streaming support. This consequently means that
+//! when a repository is cloned the entire contents of the repo are downloaded
+//! into memory, and *then* written off to disk by libgit2 afterwards. It
+//! should be possible to alleviate this problem in the future.
+//!
+//! > **NOTE**: At this time this crate likely does not support a `git push`
+//! >           operation, only clones.
+
+#![doc(html_root_url = "https://docs.rs/git2-curl/0.19")]
+#![deny(missing_docs)]
+#![warn(rust_2018_idioms)]
+#![cfg_attr(test, deny(warnings))]
+
+use std::error;
+use std::io::prelude::*;
+use std::io::{self, Cursor};
+use std::str;
+use std::sync::{Arc, Mutex, Once};
+
+use curl::easy::{Easy, List};
+use git2::transport::SmartSubtransportStream;
+use git2::transport::{Service, SmartSubtransport, Transport};
+use git2::Error;
+use log::{debug, info};
+use url::Url;
+
+struct CurlTransport {
+    handle: Arc<Mutex<Easy>>,
+    /// The URL of the remote server, e.g. "https://github.com/user/repo"
+    ///
+    /// This is an empty string until the first action is performed.
+    /// If there is an HTTP redirect, this will be updated with the new URL.
+    base_url: Arc<Mutex<String>>,
+}
+
+struct CurlSubtransport {
+    handle: Arc<Mutex<Easy>>,
+    service: &'static str,
+    url_path: &'static str,
+    base_url: Arc<Mutex<String>>,
+    method: &'static str,
+    reader: Option<Cursor<Vec<u8>>>,
+    sent_request: bool,
+}
+
+/// Register the libcurl backend for HTTP requests made by libgit2.
+///
+/// This function takes one parameter, a `handle`, which is used to perform all
+/// future HTTP requests. The handle can be previously configured with
+/// information such as proxies, SSL information, etc.
+///
+/// This function is unsafe largely for the same reasons as
+/// `git2::transport::register`:
+///
+/// * The function needs to be synchronized against all other creations of
+///   transport (any API calls to libgit2).
+/// * The function will leak `handle` as once registered it is not currently
+///   possible to unregister the backend.
+///
+/// This function may be called concurrently, but only the first `handle` will
+/// be used. All others will be discarded.
+pub unsafe fn register(handle: Easy) {
+    static INIT: Once = Once::new();
+
+    let handle = Arc::new(Mutex::new(handle));
+    let handle2 = handle.clone();
+    INIT.call_once(move || {
+        git2::transport::register("http", move |remote| factory(remote, handle.clone())).unwrap();
+        git2::transport::register("https", move |remote| factory(remote, handle2.clone())).unwrap();
+    });
+}
+
+fn factory(remote: &git2::Remote<'_>, handle: Arc<Mutex<Easy>>) -> Result<Transport, Error> {
+    Transport::smart(
+        remote,
+        true,
+        CurlTransport {
+            handle: handle,
+            base_url: Arc::new(Mutex::new(String::new())),
+        },
+    )
+}
+
+impl SmartSubtransport for CurlTransport {
+    fn action(
+        &self,
+        url: &str,
+        action: Service,
+    ) -> Result<Box<dyn SmartSubtransportStream>, Error> {
+        let mut base_url = self.base_url.lock().unwrap();
+        if base_url.len() == 0 {
+            *base_url = url.to_string();
+        }
+        let (service, path, method) = match action {
+            Service::UploadPackLs => ("upload-pack", "/info/refs?service=git-upload-pack", "GET"),
+            Service::UploadPack => ("upload-pack", "/git-upload-pack", "POST"),
+            Service::ReceivePackLs => {
+                ("receive-pack", "/info/refs?service=git-receive-pack", "GET")
+            }
+            Service::ReceivePack => ("receive-pack", "/git-receive-pack", "POST"),
+        };
+        info!("action {} {}", service, path);
+        Ok(Box::new(CurlSubtransport {
+            handle: self.handle.clone(),
+            service: service,
+            url_path: path,
+            base_url: self.base_url.clone(),
+            method: method,
+            reader: None,
+            sent_request: false,
+        }))
+    }
+
+    fn close(&self) -> Result<(), Error> {
+        Ok(()) // ...
+    }
+}
+
+impl CurlSubtransport {
+    fn err<E: Into<Box<dyn error::Error + Send + Sync>>>(&self, err: E) -> io::Error {
+        io::Error::new(io::ErrorKind::Other, err)
+    }
+
+    fn execute(&mut self, data: &[u8]) -> io::Result<()> {
+        if self.sent_request {
+            return Err(self.err("already sent HTTP request"));
+        }
+        let agent = format!("git/1.0 (git2-curl {})", env!("CARGO_PKG_VERSION"));
+
+        // Parse our input URL to figure out the host
+        let url = format!("{}{}", self.base_url.lock().unwrap(), self.url_path);
+        let parsed = Url::parse(&url).map_err(|_| self.err("invalid url, failed to parse"))?;
+        let host = match parsed.host_str() {
+            Some(host) => host,
+            None => return Err(self.err("invalid url, did not have a host")),
+        };
+
+        // Prep the request
+        debug!("request to {}", url);
+        let mut h = self.handle.lock().unwrap();
+        h.url(&url)?;
+        h.useragent(&agent)?;
+        h.follow_location(true)?;
+        match self.method {
+            "GET" => h.get(true)?,
+            "PUT" => h.put(true)?,
+            "POST" => h.post(true)?,
+            other => h.custom_request(other)?,
+        }
+
+        let mut headers = List::new();
+        headers.append(&format!("Host: {}", host))?;
+        if data.len() > 0 {
+            h.post_fields_copy(data)?;
+            headers.append(&format!(
+                "Accept: application/x-git-{}-result",
+                self.service
+            ))?;
+            headers.append(&format!(
+                "Content-Type: \
+                 application/x-git-{}-request",
+                self.service
+            ))?;
+        } else {
+            headers.append("Accept: */*")?;
+        }
+        headers.append("Expect:")?;
+        h.http_headers(headers)?;
+
+        let mut content_type = None;
+        let mut data = Vec::new();
+        {
+            let mut h = h.transfer();
+
+            // Look for the Content-Type header
+            h.header_function(|header| {
+                let header = match str::from_utf8(header) {
+                    Ok(s) => s,
+                    Err(..) => return true,
+                };
+                let mut parts = header.splitn(2, ": ");
+                let name = parts.next().unwrap();
+                let value = match parts.next() {
+                    Some(value) => value,
+                    None => return true,
+                };
+                if name.eq_ignore_ascii_case("Content-Type") {
+                    content_type = Some(value.trim().to_string());
+                }
+
+                true
+            })?;
+
+            // Collect the request's response in-memory
+            h.write_function(|buf| {
+                data.extend_from_slice(buf);
+                Ok(buf.len())
+            })?;
+
+            // Send the request
+            h.perform()?;
+        }
+
+        let code = h.response_code()?;
+        if code != 200 {
+            return Err(self.err(
+                &format!(
+                    "failed to receive HTTP 200 response: \
+                     got {}",
+                    code
+                )[..],
+            ));
+        }
+
+        // Check returned headers
+        let expected = match self.method {
+            "GET" => format!("application/x-git-{}-advertisement", self.service),
+            _ => format!("application/x-git-{}-result", self.service),
+        };
+        match content_type {
+            Some(ref content_type) if *content_type != expected => {
+                return Err(self.err(
+                    &format!(
+                        "expected a Content-Type header \
+                         with `{}` but found `{}`",
+                        expected, content_type
+                    )[..],
+                ))
+            }
+            Some(..) => {}
+            None => {
+                return Err(self.err(
+                    &format!(
+                        "expected a Content-Type header \
+                         with `{}` but didn't find one",
+                        expected
+                    )[..],
+                ))
+            }
+        }
+
+        // Ok, time to read off some data.
+        let rdr = Cursor::new(data);
+        self.reader = Some(rdr);
+
+        // If there was a redirect, update the `CurlTransport` with the new base.
+        if let Ok(Some(effective_url)) = h.effective_url() {
+            let new_base = if effective_url.ends_with(self.url_path) {
+                // Strip the action from the end.
+                &effective_url[..effective_url.len() - self.url_path.len()]
+            } else {
+                // I'm not sure if this code path makes sense, but it's what
+                // libgit does.
+                effective_url
+            };
+            *self.base_url.lock().unwrap() = new_base.to_string();
+        }
+
+        Ok(())
+    }
+}
+
+impl Read for CurlSubtransport {
+    fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> {
+        if self.reader.is_none() {
+            self.execute(&[])?;
+        }
+        self.reader.as_mut().unwrap().read(buf)
+    }
+}
+
+impl Write for CurlSubtransport {
+    fn write(&mut self, data: &[u8]) -> io::Result<usize> {
+        if self.reader.is_none() {
+            self.execute(data)?;
+        }
+        Ok(data.len())
+    }
+    fn flush(&mut self) -> io::Result<()> {
+        Ok(())
+    }
+}
diff --git a/extra/git2-curl/tests/all.rs b/extra/git2-curl/tests/all.rs
new file mode 100644
index 000000000..c7f09dd40
--- /dev/null
+++ b/extra/git2-curl/tests/all.rs
@@ -0,0 +1,74 @@
+use civet::{Config, Server};
+use conduit_git_http_backend as git_backend;
+use std::fs::File;
+use std::path::Path;
+use tempfile::TempDir;
+
+const PORT: u16 = 7848;
+
+fn main() {
+    unsafe {
+        git2_curl::register(curl::easy::Easy::new());
+    }
+
+    // Spin up a server for git-http-backend
+    let td = TempDir::new().unwrap();
+    let mut cfg = Config::new();
+    cfg.port(PORT).threads(1);
+    let _a = Server::start(cfg, git_backend::Serve(td.path().to_path_buf()));
+
+    // Prep a repo with one file called `foo`
+    let sig = git2::Signature::now("foo", "bar").unwrap();
+    let r1 = git2::Repository::init(td.path()).unwrap();
+    File::create(&td.path().join(".git").join("git-daemon-export-ok")).unwrap();
+    {
+        let mut index = r1.index().unwrap();
+        File::create(&td.path().join("foo")).unwrap();
+        index.add_path(Path::new("foo")).unwrap();
+        index.write().unwrap();
+        let tree_id = index.write_tree().unwrap();
+        r1.commit(
+            Some("HEAD"),
+            &sig,
+            &sig,
+            "test",
+            &r1.find_tree(tree_id).unwrap(),
+            &[],
+        )
+        .unwrap();
+    }
+
+    // Clone through the git-http-backend
+    let td2 = TempDir::new().unwrap();
+    let r = git2::Repository::clone(&format!("http://localhost:{}", PORT), td2.path()).unwrap();
+    assert!(File::open(&td2.path().join("foo")).is_ok());
+    {
+        File::create(&td.path().join("bar")).unwrap();
+        let mut index = r1.index().unwrap();
+        index.add_path(&Path::new("bar")).unwrap();
+        index.write().unwrap();
+        let tree_id = index.write_tree().unwrap();
+        let parent = r1.head().ok().and_then(|h| h.target()).unwrap();
+        let parent = r1.find_commit(parent).unwrap();
+        r1.commit(
+            Some("HEAD"),
+            &sig,
+            &sig,
+            "test",
+            &r1.find_tree(tree_id).unwrap(),
+            &[&parent],
+        )
+        .unwrap();
+    }
+
+    let mut remote = r.find_remote("origin").unwrap();
+    remote
+        .fetch(&["refs/heads/*:refs/heads/*"], None, None)
+        .unwrap();
+    let b = r.find_branch("master", git2::BranchType::Local).unwrap();
+    let id = b.get().target().unwrap();
+    let obj = r.find_object(id, None).unwrap();
+    r.reset(&obj, git2::ResetType::Hard, None).unwrap();
+
+    assert!(File::open(&td2.path().join("bar")).is_ok());
+}