WIP: feat(tracer): align C span code with v1-compatible stub API (v2 groundwork)

Cargo.toml

@@ -39,7 +39,8 @@ inherits = "release"
 # inheritance against this manifest when built as path dependencies. Keep this
 # list in sync with libdatadog's own `[workspace.dependencies]`; libdatadog
 # #2253 consolidated `anyhow`, `serde`, `tokio` and `tracing` to the workspace
-# level, so they are mirrored here too.
+# level, and later work moved the rest of libdatadog's shared deps there too, so
+# the full list is mirrored here.
 [workspace.dependencies]
 allocator-api2 = { version = "0.2.21", default-features = false }
 anyhow = { version = "1.0", default-features = false }

components-rs/agent_info.rs

@@ -10,7 +10,7 @@
 
 use crate::stats::apply_concentrator_config;
 use datadog_sidecar::service::agent_info::AgentInfoReader;
-use libdd_common_ffi::slice::CharSlice;
+use libdd_common_ffi::slice::{AsBytes, CharSlice};
 use libdd_data_pipeline::agent_info::schema::AgentInfoStruct;
 use std::ffi::c_char;
 use std::ffi::CString;

components-rs/common.h

@@ -437,6 +437,7 @@ typedef enum ddog_RemoteConfigProduct {
   DDOG_REMOTE_CONFIG_PRODUCT_FFE_FLAGS,
   DDOG_REMOTE_CONFIG_PRODUCT_LIVE_DEBUGGING,
   DDOG_REMOTE_CONFIG_PRODUCT_LIVE_DEBUGGING_SYMBOL_DB,
+  DDOG_REMOTE_CONFIG_PRODUCT_DEBUG,
 } ddog_RemoteConfigProduct;
 
 typedef enum ddog_SpanProbeTarget {
@@ -1208,6 +1209,11 @@ typedef struct ddog_RuntimeMetadata ddog_RuntimeMetadata;
 
 typedef struct ddog_ShmHandle ddog_ShmHandle;
 
+/**
+ * Builds a native V1 [`TracerPayloadBytes`] while interning every string once.
+ */
+typedef struct ddog_TracerPayloadV1Builder ddog_TracerPayloadV1Builder;
+
 typedef struct ddog_NativeFile {
   struct ddog_PlatformHandle_File *handle;
 } ddog_NativeFile;
@@ -1352,6 +1358,20 @@ typedef struct ddog_SenderParameters {
   ddog_CharSlice url;
 } ddog_SenderParameters;
 
+/**
+ * Payload-level tracer metadata for the V1 send path that is NOT already carried by the sender's
+ * `tracer_headers_tags`. The lang/lang_version/lang_interpreter/lang_vendor/tracer_version and
+ * container_id fields live in `SenderParameters::tracer_headers_tags` and are routed from there,
+ * so they are not duplicated here.
+ */
+typedef struct ddog_TracerMetadataV1 {
+  ddog_CharSlice hostname;
+  ddog_CharSlice env;
+  ddog_CharSlice app_version;
+  ddog_CharSlice runtime_id;
+  ddog_CharSlice git_commit_sha;
+} ddog_TracerMetadataV1;
+
 typedef enum ddog_crasht_BuildIdType {
   DDOG_CRASHT_BUILD_ID_TYPE_GNU,
   DDOG_CRASHT_BUILD_ID_TYPE_GO,