Library-config component initial skeleton

.github/workflows/test.yml

@@ -141,7 +141,7 @@ jobs:
         env:
           RUSTFLAGS: "${{ matrix.flags }}"
         run: |
-          cargo run --bin release --features profiling,telemetry,data-pipeline,symbolizer,crashtracker --release -- --out $LIBDD_OUTPUT_FOLDER
+          cargo run --bin release --features profiling,telemetry,data-pipeline,symbolizer,crashtracker,library-config --release -- --out $LIBDD_OUTPUT_FOLDER
 
       - name: 'Publish libdatadog'
         uses: actions/upload-artifact@v4

Cargo.toml

@@ -38,6 +38,8 @@ members = [
   "ddsketch",
   "tinybytes",
   "dogstatsd-client",
+  "library-config-ffi",
+  "library-config",
 ]
 
 # https://doc.rust-lang.org/cargo/reference/resolver.html#feature-resolver-version-2
@@ -66,7 +68,7 @@ debug = 2 # full debug info
 codegen-units = 1
 debug = "line-tables-only"
 lto = true
-opt-level = "s" # optimize for size
+opt-level = "s"            # optimize for size
 
 [profile.release.package.datadog-serverless-trace-mini-agent]
 strip = true
@@ -82,4 +84,4 @@ codegen-units = 1
 # proptest pulls in a dependency on libm, which changes the runtime of some math functions
 # so benchmarks are not measuring the same thing as the release build. This patch removes
 # the default dependency on libm. A PR will be opened to proptest to make this optional.
-proptest = { git = 'https://github.com/bantonsson/proptest.git', branch = "ban/avoid-libm-in-std"}
+proptest = { git = 'https://github.com/bantonsson/proptest.git', branch = "ban/avoid-libm-in-std" }

build-config-ffi.sh

@@ -0,0 +1,148 @@
+#!/usr/bin/env bash
+
+# Copyright 2021-Present Datadog, Inc. https://www.datadoghq.com/
+# SPDX-License-Identifier: Apache-2.0
+
+get_abs_filename() {
+  # $1 : relative filename
+  echo "$(cd "$(dirname "$1")" && pwd)/$(basename "$1")"
+}
+
+# Location to place all artifacts
+if [ -z $CARGO_TARGET_DIR ] ; then
+    export CARGO_TARGET_DIR=$PWD/target
+fi
+
+set -eu
+
+destdir="$1"
+
+if [ $CARGO_TARGET_DIR = $destdir ]; then
+    echo "Error: CARGO_TARGET_DIR and destdir cannot be the same"
+    exit 1
+fi
+
+mkdir -v -p "$destdir/include/datadog" "$destdir/lib/pkgconfig" "$destdir/cmake"
+
+version=$(awk -F\" '$1 ~ /^version/ { print $2 }' < profiling-ffi/Cargo.toml)
+target="$(rustc -vV | awk '/^host:/ { print $2 }')"
+shared_library_suffix=".so"
+static_library_suffix=".a"
+library_prefix="lib"
+remove_rpath=0
+fix_macos_rpath=0
+
+# Rust provides this note about the link libraries:
+# note: Link against the following native artifacts when linking against this
+# static library. The order and any duplication can be significant on some
+# platforms.
+#
+# We've decided to strip out -lgcc_s because if it's provided then it will
+# always make it into the final runtime dependencies, even if -static-libgcc is
+# provided. At least on Alpine, libgcc_s may not even exist in the users'
+# images, so -static-libgcc is recommended there.
+case "$target" in
+    "x86_64-alpine-linux-musl"|"aarch64-alpine-linux-musl")
+        # on alpine musl, Rust adds some weird runpath to cdylibs
+        remove_rpath=1
+        ;;
+
+    "x86_64-apple-darwin"|"aarch64-apple-darwin")
+
+        shared_library_suffix=".dylib"
+        # fix usage of library in macos via rpath
+        fix_macos_rpath=1
+        ;;
+
+    "x86_64-unknown-linux-gnu"|"aarch64-unknown-linux-gnu")
+        ;;
+
+    "x86_64-pc-windows-msvc")
+        shared_library_suffix=".dll"
+        static_library_suffix=".lib"
+        library_prefix=""
+        ;;
+
+    *)
+        >&2 echo "Unknown platform '${target}'"
+        exit 1
+        ;;
+esac
+
+
+cp -v LICENSE LICENSE-3rdparty.yml NOTICE "$destdir/"
+
+
+crate_dir="library-config-ffi"
+crate="datadog-library-config-ffi"
+
+
+FEATURES=(
+    "cbindgen"
+)
+
+FEATURES=$(IFS=, ; echo "${FEATURES[*]}")
+echo "Building for features: $FEATURES"
+
+# build inside the crate to use the config.toml file
+( cd "$crate_dir" && cargo build --features $FEATURES --release --target "${target}" )
+
+# Remove _ffi suffix when copying
+crate_name_underscore=$(echo "$crate" | sed 's/-/_/g')
+renamed_stem=$(echo "$crate_name_underscore" | sed 's/_ffi//g')
+
+shared_library_name="${library_prefix}${crate_name_underscore}${shared_library_suffix}"
+shared_library_rename="${library_prefix}${renamed_stem}${shared_library_suffix}"
+
+static_library_name="${library_prefix}${crate_name_underscore}${static_library_suffix}"
+static_library_rename="${library_prefix}${renamed_stem}${static_library_suffix}"
+
+cp -v "$CARGO_TARGET_DIR/${target}/release/${shared_library_name}" "$destdir/lib/${shared_library_rename}"
+cp -v "$CARGO_TARGET_DIR/${target}/release/${static_library_name}" "$destdir/lib/${static_library_rename}"
+
+shared_library_name="${shared_library_rename}"
+static_library_name="${static_library_rename}"
+
+if [[ "$remove_rpath" -eq 1 ]]; then
+    patchelf --remove-rpath "$destdir/lib/${shared_library_name}"
+fi
+
+if [[ "$fix_macos_rpath" -eq 1 ]]; then
+    install_name_tool -id @rpath/${shared_library_name} "$destdir/lib/${shared_library_name}"
+fi
+
+if command -v patchelf > /dev/null && [[ "$target" != "x86_64-pc-windows-msvc" ]]; then
+    patchelf --set-soname ${shared_library_name}  "$destdir/lib/${shared_library_rename}"
+fi
+
+# objcopy might not be available on macOS
+if command -v objcopy > /dev/null && [[ "$target" != "x86_64-pc-windows-msvc" ]]; then
+    # Remove .llvmbc section which is not useful for clients
+    objcopy --remove-section .llvmbc "$destdir/lib/${static_library_name}"
+
+    # Ship debug information separate from shared library, so that downstream packages can selectively include it
+    # https://sourceware.org/gdb/onlinedocs/gdb/Separate-Debug-Files.html
+    objcopy --only-keep-debug "$destdir/lib/$shared_library_name" "$destdir/lib/$shared_library_name.debug"
+    strip -S "$destdir/lib/$shared_library_name"
+    objcopy --add-gnu-debuglink="$destdir/lib/$shared_library_name.debug" "$destdir/lib/$shared_library_name"
+fi
+
+echo "Building tools"
+cargo build --package tools --bins
+
+echo "Generating $destdir/include/libdatadog headers..."
+rm -r $destdir/include/datadog/
+mkdir $destdir/include/datadog/
+
+CBINDGEN_HEADERS="common.h library-config.h"
+
+CBINDGEN_HEADERS_DESTS=""
+for header in $CBINDGEN_HEADERS; do
+    HEADER_DEST="$destdir/include/datadog/$header"
+    cp "$CARGO_TARGET_DIR/include/datadog/$header" "$HEADER_DEST"
+    CBINDGEN_HEADERS_DESTS="$CBINDGEN_HEADERS_DESTS $HEADER_DEST"
+done
+
+"$CARGO_TARGET_DIR"/debug/dedup_headers $CBINDGEN_HEADERS_DESTS
+
+echo "Done."

build-profiling-ffi.sh

@@ -228,9 +228,11 @@ rm -r $destdir/include/datadog/
 mkdir $destdir/include/datadog/
 
 CBINDGEN_HEADERS="common.h profiling.h telemetry.h crashtracker.h data-pipeline.h"
-# When optional features are added, don't forget to also include thei headers here
+# When optional features are added, don't forget to also include the headers here
 case $ARG_FEATURES in
+    datadog-library-config-ffi) CBINDGEN_HEADERS="$CBINDGEN_HEADERS library-config.h"
 esac
+
 CBINDGEN_HEADERS_DESTS=""
 for header in $CBINDGEN_HEADERS; do
     HEADER_DEST="$destdir/include/datadog/$header"

builder/Cargo.toml

@@ -13,6 +13,7 @@ profiling = []
 telemetry = []
 data-pipeline = []
 symbolizer = []
+library-config = []
 
 [lib]
 bench = false

builder/src/bin/release.rs

@@ -72,6 +72,8 @@ pub fn main() {
         f.push("crashtracker-ffi".to_string());
         #[cfg(feature = "symbolizer")]
         f.push("symbolizer".to_string());
+        #[cfg(feature = "library-config")]
+        f.push("datadog-library-config-ffi".to_string());
         f
     };
 

builder/src/profiling.rs

@@ -37,6 +37,8 @@ impl Profiling {
         headers.push("data-pipeline.h");
         #[cfg(feature = "symbolizer")]
         headers.push("blazesym.h");
+        #[cfg(feature = "library-config")]
+        headers.push("library-config.h");
 
         let mut origin_path: PathBuf = [&self.source_include, "dummy.h"].iter().collect();
         let mut target_path: PathBuf = [&self.target_include, "dummy.h"].iter().collect();

ddcommon-ffi/src/cstr.rs

@@ -0,0 +1,102 @@
+// Copyright 2021-Present Datadog, Inc. https://www.datadoghq.com/
+// SPDX-License-Identifier: Apache-2.0
+
+use core::fmt;
+use std::{
+    ffi::c_char,
+    marker::PhantomData,
+    mem::{self, ManuallyDrop},
+    ptr::{self, NonNull},
+};
+
+/// Ffi safe type representing a borrowed null-terminated C array
+/// Equivalent to a std::ffi::CStr
+#[repr(C)]
+pub struct CStr<'a> {
+    /// Null terminated char array
+    ptr: ptr::NonNull<c_char>,
+    /// Length of the array, not counting the null-terminator
+    length: usize,
+    _lifetime_marker: std::marker::PhantomData<&'a c_char>,
+}
+
+impl<'a> CStr<'a> {
+    pub fn from_std(s: &'a std::ffi::CStr) -> Self {
+        Self {
+            ptr: unsafe { ptr::NonNull::new_unchecked(s.as_ptr().cast_mut()) },
+            length: s.to_bytes().len() - 1,
+            _lifetime_marker: std::marker::PhantomData,
+        }
+    }
+
+    pub fn into_std(&self) -> &'a std::ffi::CStr {
+        unsafe {
+            std::ffi::CStr::from_bytes_with_nul_unchecked(std::slice::from_raw_parts(
+                self.ptr.as_ptr().cast_const().cast(),
+                self.length,
+            ))
+        }
+    }
+}
+
+/// Ffi safe type representing an owned null-terminated C array
+/// Equivalent to a std::ffi::CString
+#[repr(C)]
+pub struct CString {
+    /// Null terminated char array
+    ptr: ptr::NonNull<c_char>,
+    /// Length of the array, not counting the null-terminator
+    length: usize,
+}
+
+impl fmt::Debug for CString {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        self.as_cstr().into_std().fmt(f)
+    }
+}
+
+impl CString {
+    pub fn new<T: Into<Vec<u8>>>(t: T) -> Result<Self, std::ffi::NulError> {
+        Ok(Self::from_std(std::ffi::CString::new(t)?))
+    }
+
+    pub fn as_cstr(&self) -> CStr<'_> {
+        CStr {
+            ptr: self.ptr,
+            length: self.length + 1, // +1 for the null terminator
+            _lifetime_marker: PhantomData,
+        }
+    }
+
+    pub fn from_std(s: std::ffi::CString) -> Self {
+        let s = ManuallyDrop::new(s);
+        Self {
+            ptr: unsafe { ptr::NonNull::new_unchecked(s.as_ptr().cast_mut()) },
+            length: s.to_bytes().len(),
+        }
+    }
+
+    pub fn into_std(self) -> std::ffi::CString {
+        let s = ManuallyDrop::new(self);
+        unsafe {
+            std::ffi::CString::from_vec_with_nul_unchecked(Vec::from_raw_parts(
+                s.ptr.as_ptr().cast(),
+                s.length,
+                s.length,
+            ))
+        }
+    }
+}
+
+impl Drop for CString {
+    fn drop(&mut self) {
+        let ptr = mem::replace(&mut self.ptr, NonNull::dangling());
+        drop(unsafe {
+            std::ffi::CString::from_vec_with_nul_unchecked(Vec::from_raw_parts(
+                ptr.as_ptr().cast(),
+                self.length,
+                self.length,
+            ))
+        });
+    }
+}