feat: c++ bindings (#41)

* feat: c++ bindings for resolvo

* fix: redefinition errors

.clang-format

@@ -0,0 +1,5 @@
+BasedOnStyle: Google
+IndentWidth: 4
+IndentAccessModifiers: false
+AccessModifierOffset: -4
+ColumnLimit: 100

.gitattributes

@@ -0,0 +1,3 @@
+# GitHub syntax highlighting
+pixi.lock linguist-language=YAML
+

.github/workflows/cpp-test.yml

@@ -0,0 +1,47 @@
+on:
+  push:
+    branches:
+    - "main"
+  pull_request:
+
+name: C++
+
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
+
+jobs:
+  format:
+    name: Format and Lint
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout source code
+        uses: actions/checkout@v4
+
+      - uses: prefix-dev/[email protected]
+        with:
+          environments: format-cpp
+
+      - name: Ensure code is properly formatted
+        run: |
+          pixi run format-cpp
+          git diff --exit-code
+
+  test:
+    strategy:
+      fail-fast: false
+      matrix:
+        os: [ubuntu-20.04, macOS-latest, macOS-14, windows-latest ]
+    runs-on: ${{ matrix.os }}
+    needs: [ format ]
+    steps:
+      - name: Checkout source code
+        uses: actions/checkout@v4
+
+      - uses: prefix-dev/[email protected]
+        with:
+          environments: test-cpp
+
+      - name: Run the tests
+        run: |
+          pixi run test-cpp

.github/workflows/rust-compile.yml

@@ -43,7 +43,7 @@ jobs:
         run: cargo clippy
 
   build:
-    name: ubuntu-latest
+    name: Test
     runs-on: ubuntu-latest
     needs: [ format_and_lint ]
     steps:

.gitignore

@@ -18,3 +18,9 @@ Cargo.lock
 *.pdb
 
 **/.DS_Store
+
+build/
+# pixi environments
+.pixi
+*.egg-info
+

CMakeLists.txt

@@ -0,0 +1,34 @@
+cmake_minimum_required(VERSION 3.21)
+
+project(resolvo LANGUAGES CXX)
+
+set(CMAKE_CXX_STANDARD 17)
+set(CMAKE_CXX_STANDARD_REQUIRED ON)
+
+include(FeatureSummary)
+
+option(RESOLVO_BUILD_TESTING "Build tests" OFF)
+add_feature_info(RESOLVO_BUILD_TESTING RESOLVO_BUILD_TESTING "configure whether to build the test suite")
+include(CTest)
+
+set(RESOLVO_IS_TOPLEVEL_BUILD TRUE)
+
+# Place all compiled examples into the same bin directory
+# on Windows, where we'll also put the dll
+if (WIN32)
+    set(CMAKE_RUNTIME_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR}/bin)
+    set(CMAKE_LIBRARY_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR}/bin)
+    set(CMAKE_LIBRARY_OUTPUT_DIRECTORY_DEBUG ${CMAKE_BINARY_DIR}/bin/debug)
+    set(CMAKE_LIBRARY_OUTPUT_DIRECTORY_RELEASE ${CMAKE_BINARY_DIR}/bin/release)
+elseif(APPLE)
+    # On macOS, the resolvo_cpp.dylib's install_name uses @rpath. CMake doesn't
+    # set BUILD_RPATH for imported targets though, so include the directory here
+    # by hand in the rpath used to build binaries in the build tree (such as our
+    # examples or tests).
+    set(CMAKE_BUILD_RPATH ${CMAKE_BINARY_DIR}/cpp)
+endif()
+
+add_subdirectory(cpp/)
+
+feature_summary(WHAT ENABLED_FEATURES DESCRIPTION "Enabled features:")
+feature_summary(WHAT DISABLED_FEATURES DESCRIPTION "Disabled features:")

Cargo.toml

@@ -1,19 +1,31 @@
 [workspace]
-members = ["tools/solve-snapshot"]
+members = ["cpp", "tools/*"]
+resolver = "2"
 
-[package]
+[workspace.package]
 name = "resolvo"
 version = "0.6.1"
 authors = ["Adolfo Ochagavía <[email protected]>", "Bas Zalmstra <[email protected]>", "Tim de Jager <[email protected]>"]
-description = "Fast package resolver written in Rust (CDCL based SAT solving)"
-keywords = ["dependency", "solver", "version"]
-categories = ["algorithms"]
 homepage = "https://github.com/mamba-org/resolvo"
 repository = "https://github.com/mamba-org/resolvo"
 license = "BSD-3-Clause"
 edition = "2021"
 readme = "README.md"
-resolver = "2"
+keywords = ["dependency", "solver", "version"]
+categories= ["algorithms"]
+
+[package]
+name = "resolvo"
+version.workspace = true
+authors.workspace = true
+description= "Fast package resolver written in Rust (CDCL based SAT solving)"
+keywords.workspace = true
+categories.workspace = true
+homepage.workspace = true
+repository.workspace = true
+license.workspace = true
+edition.workspace = true
+readme.workspace = true
 
 [dependencies]
 ahash = "0.8.11"

cpp/CMakeLists.txt

@@ -0,0 +1,86 @@
+cmake_minimum_required(VERSION 3.21)
+
+# Select C++ and C as languages, as Corrosion needs ${CMAKE_C_COMPILER}
+# for linking
+project(Resolvo LANGUAGES C CXX VERSION 0.1.0)
+
+# Add the Corrosion dependency (used to build Rust code)
+include(FetchContent)
+FetchContent_Declare(
+    Corrosion
+    GIT_REPOSITORY https://github.com/corrosion-rs/corrosion.git
+    GIT_TAG v0.4.9
+)
+FetchContent_MakeAvailable(Corrosion)
+
+# Add the Corrosion CMake module path to the list of paths to search for modules
+list(PREPEND CMAKE_MODULE_PATH ${Corrosion_SOURCE_DIR}/cmake)
+find_package(Rust 1.75 REQUIRED MODULE)
+
+option(BUILD_SHARED_LIBS "Build Resolvo as shared library" ON)
+
+set(RESOLVO_LIBRARY_CARGO_FLAGS "" CACHE STRING
+    "Flags to pass to cargo when building the Resolvo runtime library")
+
+if(BUILD_SHARED_LIBS)
+    set(rustc_lib_type "cdylib")
+    set(resolvo_cpp_impl "resolvo_cpp-shared")
+    set(cmake_lib_type "SHARED")
+else()
+    set(rustc_lib_type "staticlib")
+    set(resolvo_cpp_impl "resolvo_cpp-static")
+    set(cmake_lib_type "STATIC")
+endif()
+
+corrosion_import_crate(MANIFEST_PATH "${CMAKE_CURRENT_SOURCE_DIR}/Cargo.toml"
+    CRATES resolvo_cpp CRATE_TYPES bin ${rustc_lib_type})
+
+add_library(Resolvo INTERFACE)
+add_library(Resolvo::Resolvo ALIAS Resolvo)
+target_link_libraries(Resolvo INTERFACE resolvo_cpp)
+
+set_property(
+    TARGET resolvo_cpp
+    APPEND
+    PROPERTY CORROSION_ENVIRONMENT_VARIABLES
+    "RESOLVO_GENERATED_INCLUDE_DIR=${CMAKE_CURRENT_BINARY_DIR}/generated_include/"
+)
+
+file(GLOB api_headers RELATIVE "${CMAKE_CURRENT_SOURCE_DIR}/include/"
+        "${CMAKE_CURRENT_SOURCE_DIR}/include/*.h")
+
+foreach(header IN LISTS api_headers)
+    set_property(TARGET Resolvo APPEND PROPERTY PUBLIC_HEADER include/${header})
+endforeach()
+
+set(generated_headers
+    ${CMAKE_CURRENT_BINARY_DIR}/generated_include/resolvo_vector_internal.h
+    ${CMAKE_CURRENT_BINARY_DIR}/generated_include/resolvo_string_internal.h
+    ${CMAKE_CURRENT_BINARY_DIR}/generated_include/resolvo_internal.h
+)
+
+foreach(header IN LISTS generated_headers)
+    set_property(TARGET Resolvo APPEND PROPERTY PUBLIC_HEADER ${header})
+endforeach()
+
+target_include_directories(Resolvo INTERFACE
+    $<BUILD_INTERFACE:${CMAKE_CURRENT_BINARY_DIR}/generated_include>
+    $<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}/include>
+    $<INSTALL_INTERFACE:include/resolvo>
+)
+
+export(TARGETS Resolvo resolvo_cpp
+        NAMESPACE Resolvo:: FILE "${CMAKE_BINARY_DIR}/lib/cmake/Resolvo/ResolvoTargets.cmake")
+install(EXPORT ResolvoTargets NAMESPACE Resolvo:: DESTINATION lib/cmake/Resolvo)
+install(TARGETS Resolvo resolvo_cpp
+    EXPORT ResolvoTargets LIBRARY DESTINATION lib PUBLIC_HEADER DESTINATION include/resolvo)
+
+install(FILES $<TARGET_FILE:${resolvo_cpp_impl}> TYPE LIB)
+
+if(WIN32)
+    install(FILES $<TARGET_LINKER_FILE:${resolvo_cpp_impl}> TYPE LIB)
+endif()
+
+if(RESOLVO_BUILD_TESTING)
+    add_subdirectory(tests)
+endif()

cpp/Cargo.toml

@@ -0,0 +1,24 @@
+[package]
+name = "resolvo_cpp"
+description = "Resolvo C++ integration"
+version.workspace = true
+authors.workspace = true
+keywords.workspace = true
+categories.workspace = true
+homepage.workspace = true
+repository.workspace = true
+license.workspace = true
+edition.workspace = true
+readme.workspace = true
+publish = false
+
+[lib]
+crate-type = ["lib", "cdylib", "staticlib"]
+
+[dependencies]
+resolvo = { path = "../" }
+
+[build-dependencies]
+anyhow = "1"
+cbindgen = "0.26.0"
+

cpp/build.rs

@@ -0,0 +1,92 @@
+use std::path::{Path, PathBuf};
+
+use anyhow::Context;
+
+fn main() -> anyhow::Result<()> {
+    let manifest_dir = PathBuf::from(std::env::var_os("CARGO_MANIFEST_DIR").unwrap());
+
+    println!("cargo:rerun-if-env-changed=RESOLVO_GENERATED_INCLUDE_DIR");
+    let output_dir = std::env::var_os("RESOLVO_GENERATED_INCLUDE_DIR").unwrap_or_else(|| {
+        Path::new(&std::env::var_os("OUT_DIR").unwrap())
+            .join("generated_include")
+            .into()
+    });
+    let output_dir = Path::new(&output_dir);
+
+    println!("cargo:GENERATED_INCLUDE_DIR={}", output_dir.display());
+
+    std::fs::create_dir_all(output_dir).context("Could not create the include directory")?;
+
+    let mut default_config = cbindgen::Config::default();
+    default_config.macro_expansion.bitflags = true;
+    default_config.pragma_once = true;
+    default_config.include_version = true;
+    default_config.namespaces = Some(vec!["resolvo".into(), "cbindgen_private".into()]);
+    default_config.line_length = 100;
+    default_config.tab_width = 4;
+    default_config.language = cbindgen::Language::Cxx;
+    default_config.cpp_compat = true;
+    default_config.documentation = true;
+    default_config.documentation_style = cbindgen::DocumentationStyle::Doxy;
+    default_config.structure.associated_constants_in_body = true;
+    default_config.constant.allow_constexpr = true;
+    default_config.export.exclude = vec!["Slice".into()];
+
+    cbindgen::Builder::new()
+        .with_config(default_config.clone())
+        .with_src(manifest_dir.join("src/vector.rs"))
+        .generate()
+        .context("Unable to generate bindings for resolvo_vector_internal.h")?
+        .write_to_file(output_dir.join("resolvo_vector_internal.h"));
+
+    let mut string_config = default_config.clone();
+    string_config.export.exclude = vec!["String".into()];
+
+    cbindgen::Builder::new()
+        .with_config(string_config.clone())
+        .with_src(manifest_dir.join("src/string.rs"))
+        .with_after_include("namespace resolvo { struct String; }")
+        .generate()
+        .context("Unable to generate bindings for resolvo_string_internal.h")?
+        .write_to_file(output_dir.join("resolvo_string_internal.h"));
+
+    let mut config = default_config.clone();
+    config.export.exclude.extend(vec![
+        "Vector".into(),
+        "resolvo_vector_free".into(),
+        "resolvo_vector_allocate".into(),
+        "resolvo_vector_empty".into(),
+        "String".into(),
+        "resolvo_string_bytes".into(),
+        "resolvo_string_drop".into(),
+        "resolvo_string_clone".into(),
+        "resolvo_string_from_bytes".into(),
+    ]);
+    config.export.body.insert(
+        "Slice".to_owned(),
+        r"
+    const T &operator[](int i) const { return ptr[i]; }
+    /// Note: this doesn't initialize Slice properly, but we need to keep the struct as compatible with C
+    constexpr Slice() = default;
+    /// Rust uses a NonNull, so even empty slices shouldn't use nullptr
+    constexpr Slice(const T *ptr, uintptr_t len) : ptr(ptr ? const_cast<T*>(ptr) : reinterpret_cast<T*>(sizeof(T))), len(len) {}"
+            .to_owned(),
+    );
+
+    cbindgen::Builder::new()
+        .with_config(config.clone())
+        .with_src(manifest_dir.join("src/lib.rs"))
+        .with_include("resolvo_slice.h")
+        .with_include("resolvo_vector.h")
+        .with_include("resolvo_string.h")
+        .generate()
+        .context("Unable to generate bindings for resolvo_internal.h")?
+        .write_to_file(output_dir.join("resolvo_internal.h"));
+
+    println!("cargo:rerun-if-changed=src/lib.rs");
+    println!("cargo:rerun-if-changed=src/slice.rs");
+    println!("cargo:rerun-if-changed=src/string.rs");
+    println!("cargo:rerun-if-changed=src/vector.rs");
+
+    Ok(())
+}

cpp/include/resolvo.h

@@ -0,0 +1,37 @@
+#pragma once
+
+#include "resolvo_dependency_provider.h"
+#include "resolvo_internal.h"
+
+namespace resolvo {
+
+/**
+ * Called to solve a package problem.
+ *
+ * If the solve was successful, an empty string is returned and selected solvable ids will be
+ * stored in `result`. If the solve was unsuccesfull an error describing the reason is returned and
+ * the result vector will be empty.
+ */
+inline String solve(DependencyProvider &provider, Slice<VersionSetId> requirements,
+                    Slice<VersionSetId> constraints, Vector<SolvableId> &result) {
+    cbindgen_private::DependencyProvider bridge{
+        static_cast<void *>(&provider),
+        private_api::bridge_display_solvable,
+        private_api::bridge_display_solvable_name,
+        private_api::bridge_display_merged_solvables,
+        private_api::bridge_display_name,
+        private_api::bridge_display_version_set,
+        private_api::bridge_display_string,
+        private_api::bridge_version_set_name,
+        private_api::bridge_solvable_name,
+        private_api::bridge_get_candidates,
+        private_api::bridge_sort_candidates,
+        private_api::bridge_filter_candidates,
+        private_api::bridge_get_dependencies,
+    };
+
+    String error;
+    cbindgen_private::resolvo_solve(&bridge, requirements, constraints, &error, &result);
+    return error;
+}
+}  // namespace resolvo