Create a new ddcommon-ffi crate and factorise generic ffi code inside…

… it (#24)

* Create a ddcommon-ffi crate, to contain generic ffi code that can be used by both ddprof and ddtelemetry ffis
* Move the Slice, Vec and Tag implementations to the ddcommon-ffi crate
* Rename the generated header from `ddprof/ffi.h` to `datadog/common.h` and `datadog/profiling.h`
* Add a tool crate for custom scripts used during build, that are to complex to be implemented in bash
* Add a step to move every struct and enum definition from the ddprof ffi header to the ddcommon ffi header
* Rename the namspace prefix from ddprof_ffi_* to ddog_*

Co-authored-by: Levi Morrison <levi.morrison@datadoghq.com>

Cargo.toml

@@ -8,7 +8,9 @@ members = [
     "ddprof-ffi",
     "ddprof-profiles",
     "ddcommon",
+    "ddcommon-ffi",
     "ddtelemetry",
+    "tools",
 ]
 # https://doc.rust-lang.org/cargo/reference/resolver.html#feature-resolver-version-2
 resolver = "2"

LICENSE-3rdparty.yml

@@ -1,5 +1,5 @@
 ---
-root_name: "ddprof, ddprof-exporter, ddcommon, ddprof-profiles, ddprof-ffi"
+root_name: "ddprof, ddprof-exporter, ddcommon, ddprof-profiles, ddprof-ffi, ddcommon-ffi, ddtelemetry"
 third_party_libraries:
   - package_name: aho-corasick
     package_version: 0.7.18

cmake/DDProfConfig.cmake.in

@@ -9,7 +9,7 @@ else ()
   set(DDProf_ROOT "${CMAKE_CURRENT_SOURCE_DIR}/..")
 endif ()
 
-find_path(DDProf_INCLUDE_DIR ddprof/ffi.h
+find_path(DDProf_INCLUDE_DIR datadog/profiling.h
   HINTS ${DDProf_ROOT}/include
 )
 

ddcommon-ffi/Cargo.toml

@@ -0,0 +1,14 @@
+# Unless explicitly stated otherwise all files in this repository are licensed under the Apache License Version 2.0.
+# This product includes software developed at Datadog (https://www.datadoghq.com/). Copyright 2021-Present Datadog, Inc.
+
+[package]
+name = "ddcommon-ffi"
+version = "0.7.0-rc.1"
+edition = "2021"
+license = "Apache-2.0"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+ddcommon = { path = "../ddcommon", version = "0.7.0-rc.1" }
+anyhow = "1.0"

ddcommon-ffi/cbindgen.toml

@@ -0,0 +1,51 @@
+# Unless explicitly stated otherwise all files in this repository are licensed under the Apache License Version 2.0.
+# This product includes software developed at Datadog (https://www.datadoghq.com/). Copyright 2021-Present Datadog, Inc.
+
+language = "C"
+tab_width = 2
+header = """// Unless explicitly stated otherwise all files in this repository are licensed under the Apache License Version 2.0.
+// This product includes software developed at Datadog (https://www.datadoghq.com/). Copyright 2021-Present Datadog, Inc.
+"""
+include_guard = "DDOG_COMMON_H"
+style = "both"
+
+no_includes = true
+sys_includes = ["stdbool.h", "stddef.h", "stdint.h"]
+
+after_includes = """
+
+#if defined(_MSC_VER)
+#define DDOG_CHARSLICE_C(string) \\
+/* NOTE: Compilation fails if you pass in a char* instead of a literal */ {.ptr = "" string, .len = sizeof(string) - 1}
+#else
+#define DDOG_CHARSLICE_C(string) \\
+/* NOTE: Compilation fails if you pass in a char* instead of a literal */ ((ddog_CharSlice){ .ptr = "" string, .len = sizeof(string) - 1 })
+#endif
+
+#if defined(__cplusplus) && (__cplusplus >= 201703L)
+#  define DDOG_CHECK_RETURN [[nodiscard]]
+#elif defined(_Check_return_) /* SAL */
+#  define DDOG_CHECK_RETURN _Check_return_
+#elif (defined(__has_attribute) && __has_attribute(warn_unused_result)) || \\
+      (defined(__GNUC__) && (__GNUC__ >= 4))
+#  define DDOG_CHECK_RETURN __attribute__((__warn_unused_result__))
+#else
+#  define DDOG_CHECK_RETURN
+#endif"""
+
+[export]
+prefix = "ddog_"
+
+[export.mangle]
+rename_types="SnakeCase"
+
+[enum]
+prefix_with_name = true
+rename_variants = "ScreamingSnakeCase"
+
+[fn]
+must_use = "DDOG_CHECK_RETURN"
+
+[parse]
+parse_deps = true
+include = ["ddcommon"]

ddcommon-ffi/src/lib.rs

@@ -0,0 +1,9 @@
+// Unless explicitly stated otherwise all files in this repository are licensed under the Apache License Version 2.0.
+// This product includes software developed at Datadog (https://www.datadoghq.com/). Copyright 2021-Present Datadog, Inc.
+
+pub mod slice;
+pub mod tags;
+pub mod vec;
+
+pub use slice::Slice;
+pub use vec::Vec;

ddprof-ffi/src/slice.rs → ddcommon-ffi/src/slice.rs

@@ -185,7 +185,7 @@ impl<'a> From<&'a str> for Slice<'a, c_char> {
 mod test {
     use std::os::raw::c_char;
 
-    use crate::*;
+    use crate::slice::*;
 
     #[test]
     fn slice_from_into_slice() {

ddprof-ffi/src/tags.rs → ddcommon-ffi/src/tags.rs

@@ -1,17 +1,17 @@
 // Unless explicitly stated otherwise all files in this repository are licensed under the Apache License Version 2.0.
 // This product includes software developed at Datadog (https://www.datadoghq.com/). Copyright 2022-Present Datadog, Inc.
 
-use crate::{AsBytes, CharSlice};
+use crate::{slice::AsBytes, slice::CharSlice};
 use ddcommon::tag::{parse_tags, Tag};
 
 #[must_use]
 #[no_mangle]
-pub extern "C" fn ddprof_ffi_Vec_tag_new() -> crate::Vec<Tag> {
+pub extern "C" fn ddog_Vec_tag_new() -> crate::Vec<Tag> {
     crate::Vec::default()
 }
 
 #[no_mangle]
-pub extern "C" fn ddprof_ffi_Vec_tag_drop(_: crate::Vec<Tag>) {}
+pub extern "C" fn ddog_Vec_tag_drop(_: crate::Vec<Tag>) {}
 
 #[repr(C)]
 pub enum PushTagResult {
@@ -20,7 +20,7 @@ pub enum PushTagResult {
 }
 
 #[no_mangle]
-pub extern "C" fn ddprof_ffi_PushTagResult_drop(_: PushTagResult) {}
+pub extern "C" fn ddog_PushTagResult_drop(_: PushTagResult) {}
 
 /// Creates a new Tag from the provided `key` and `value` by doing a utf8
 /// lossy conversion, and pushes into the `vec`. The strings `key` and `value`
@@ -32,7 +32,7 @@ pub extern "C" fn ddprof_ffi_PushTagResult_drop(_: PushTagResult) {}
 /// `.len` properties claim.
 #[must_use]
 #[no_mangle]
-pub unsafe extern "C" fn ddprof_ffi_Vec_tag_push(
+pub unsafe extern "C" fn ddog_Vec_tag_push(
     vec: &mut crate::Vec<Tag>,
     key: CharSlice,
     value: CharSlice,
@@ -59,7 +59,7 @@ pub struct ParseTagsResult {
 /// .len property.
 #[must_use]
 #[no_mangle]
-pub unsafe extern "C" fn ddprof_ffi_Vec_tag_parse(string: CharSlice) -> ParseTagsResult {
+pub unsafe extern "C" fn ddog_Vec_tag_parse(string: CharSlice) -> ParseTagsResult {
     let string = string.to_utf8_lossy();
     let (tags, error) = parse_tags(string.as_ref());
     ParseTagsResult {
@@ -75,22 +75,21 @@ mod tests {
     #[test]
     fn empty_tag_name() {
         unsafe {
-            let mut tags = ddprof_ffi_Vec_tag_new();
-            let result =
-                ddprof_ffi_Vec_tag_push(&mut tags, CharSlice::from(""), CharSlice::from("woof"));
+            let mut tags = ddog_Vec_tag_new();
+            let result = ddog_Vec_tag_push(&mut tags, CharSlice::from(""), CharSlice::from("woof"));
             assert!(!matches!(result, PushTagResult::Ok));
         }
     }
 
     #[test]
     fn test_lifetimes() {
-        let mut tags = ddprof_ffi_Vec_tag_new();
+        let mut tags = ddog_Vec_tag_new();
         unsafe {
             // make a string here so it has a scoped lifetime
             let key = String::from("key1");
             {
                 let value = String::from("value1");
-                let result = ddprof_ffi_Vec_tag_push(
+                let result = ddog_Vec_tag_push(
                     &mut tags,
                     CharSlice::from(key.as_str()),
                     CharSlice::from(value.as_str()),
@@ -106,12 +105,9 @@ mod tests {
     #[test]
     fn test_get() {
         unsafe {
-            let mut tags = ddprof_ffi_Vec_tag_new();
-            let result = ddprof_ffi_Vec_tag_push(
-                &mut tags,
-                CharSlice::from("sound"),
-                CharSlice::from("woof"),
-            );
+            let mut tags = ddog_Vec_tag_new();
+            let result =
+                ddog_Vec_tag_push(&mut tags, CharSlice::from("sound"), CharSlice::from("woof"));
             assert!(matches!(result, PushTagResult::Ok));
             assert_eq!(1, tags.len());
             assert_eq!("sound:woof", tags.get(0).unwrap().to_string());
@@ -123,7 +119,7 @@ mod tests {
         let dd_tags = "env:staging:east, tags:, env_staging:east"; // contains an error
 
         // SAFETY: CharSlices from Rust strings are safe.
-        let result = unsafe { ddprof_ffi_Vec_tag_parse(CharSlice::from(dd_tags)) };
+        let result = unsafe { ddog_Vec_tag_parse(CharSlice::from(dd_tags)) };
         assert_eq!(2, result.tags.len());
         assert_eq!("env:staging:east", result.tags.get(0).unwrap().to_string());
         assert_eq!("env_staging:east", result.tags.get(1).unwrap().to_string());

ddprof-ffi/src/vec.rs → ddcommon-ffi/src/vec.rs

@@ -3,7 +3,7 @@
 
 extern crate alloc;
 
-use crate::Slice;
+use crate::slice::Slice;
 use std::io::Write;
 use std::marker::PhantomData;
 use std::mem::ManuallyDrop;

ddprof-ffi/Cargo.toml

@@ -18,5 +18,6 @@ ddprof-exporter = { path = "../ddprof-exporter", version = "0.7.0-rc.1" }
 ddprof-profiles = { path = "../ddprof-profiles", version = "0.7.0-rc.1" }
 hyper = {version = "0.14", default-features = false}
 ddcommon = { path = "../ddcommon", version = "0.7.0-rc.1" }
+ddcommon-ffi = { path = "../ddcommon-ffi", version = "0.7.0-rc.1" }
 libc = "0.2"
 tokio-util = "0.7.1"

ddprof-ffi/cbindgen.toml

@@ -6,35 +6,15 @@ tab_width = 2
 header = """// Unless explicitly stated otherwise all files in this repository are licensed under the Apache License Version 2.0.
 // This product includes software developed at Datadog (https://www.datadoghq.com/). Copyright 2021-Present Datadog, Inc.
 """
-include_guard = "DDPROF_FFI_H"
+include_guard = "DDOG_PROFILING_H"
 style = "both"
 
 no_includes = true
 sys_includes = ["stdbool.h", "stddef.h", "stdint.h"]
-
-after_includes = """
-
-#if defined(_MSC_VER)
-#define DDPROF_FFI_CHARSLICE_C(string) \\
-/* NOTE: Compilation fails if you pass in a char* instead of a literal */ {.ptr = "" string, .len = sizeof(string) - 1}
-#else
-#define DDPROF_FFI_CHARSLICE_C(string) \\
-/* NOTE: Compilation fails if you pass in a char* instead of a literal */ ((ddprof_ffi_CharSlice){ .ptr = "" string, .len = sizeof(string) - 1 })
-#endif
-
-#if defined(__cplusplus) && (__cplusplus >= 201703L)
-#  define DD_CHECK_RETURN [[nodiscard]]
-#elif defined(_Check_return_) /* SAL */
-#  define DD_CHECK_RETURN _Check_return_
-#elif (defined(__has_attribute) && __has_attribute(warn_unused_result)) || \\
-      (defined(__GNUC__) && (__GNUC__ >= 4))
-#  define DD_CHECK_RETURN __attribute__((__warn_unused_result__))
-#else
-#  define DD_CHECK_RETURN
-#endif"""
+includes = ["datadog/common.h"]
 
 [export]
-prefix = "ddprof_ffi_"
+prefix = "ddog_"
 
 [export.mangle]
 rename_types="SnakeCase"
@@ -44,8 +24,8 @@ prefix_with_name = true
 rename_variants = "ScreamingSnakeCase"
 
 [fn]
-must_use = "DD_CHECK_RETURN"
+must_use = "DDOG_CHECK_RETURN"
 
 [parse]
 parse_deps = true
-include = ["ddcommon", "ddprof-exporter", "ddprof-profiles", "ux"]
+include = ["ddcommon", "ddcommon-ffi", "ddprof-exporter", "ddprof-profiles", "ux"]