[crashtracker] Enable dynamic updating of metadata and config at runtime

crashtracker/src/api.rs

@@ -2,12 +2,11 @@
 // This product includes software developed at Datadog (https://www.datadoghq.com/). Copyright 2023-Present Datadog, Inc.
 #![cfg(unix)]
 
+use crate::crash_handler::{register_crash_handlers, setup_receiver};
+
 use super::{
     counters::reset_counters,
-    crash_handler::{
-        register_crash_handlers, replace_receiver, restore_old_handlers, setup_receiver,
-        shutdown_receiver,
-    },
+    crash_handler::{replace_receiver, restore_old_handlers, shutdown_receiver},
 };
 use ddcommon::tag::Tag;
 use ddcommon::Endpoint;
@@ -100,7 +99,7 @@ impl CrashtrackerConfiguration {
 ///     This function is not atomic. A crash during its execution may lead to
 ///     unexpected crash-handling behaviour.
 pub fn shutdown_crash_handler() -> anyhow::Result<()> {
-    restore_old_handlers()?;
+    restore_old_handlers(false)?;
     shutdown_receiver()?;
     Ok(())
 }
@@ -134,7 +133,7 @@ pub fn on_fork(
     // https://man7.org/linux/man-pages/man2/sigaltstack.2.html
 
     // See function level comment about why we do this.
-    replace_receiver(&config, &metadata)?;
+    replace_receiver(config, metadata)?;
     Ok(())
 }
 
@@ -154,8 +153,9 @@ pub fn init(
 ) -> anyhow::Result<()> {
     // Setup the receiver first, so that if there is a crash detected it has
     // somewhere to go.
-    setup_receiver(&config, &metadata)?;
-    register_crash_handlers(&config)?;
+    let create_alt_stack = config.create_alt_stack;
+    setup_receiver(config, metadata)?;
+    register_crash_handlers(create_alt_stack)?;
     Ok(())
 }
 
@@ -169,9 +169,11 @@ pub fn init(
 // ./build-profiling-ffi /tmp/libdatadog
 // mkdir /tmp/crashreports
 // look in /tmp/crashreports for the crash reports and output files
+// Commented out since `ignore` doesn't work in CI.
 //#[test]
 fn test_crash() {
     use crate::begin_profiling_op;
+    use crate::update_metadata;
     use chrono::Utc;
     use ddcommon::parse_uri;
 
@@ -208,6 +210,16 @@ fn test_crash() {
     );
     init(config, metadata).expect("not to fail");
     begin_profiling_op(crate::ProfilingOpTypes::CollectingSample).expect("Not to fail");
+
+    let tag = Tag::new("apple", "banana").expect("tag");
+    let metadata2 = CrashtrackerMetadata::new(
+        "libname".to_string(),
+        "version".to_string(),
+        "family".to_string(),
+        vec![tag],
+    );
+    update_metadata(metadata2).expect("metadata");
+
     let p: *const u32 = std::ptr::null();
     let q = unsafe { *p };
     assert_eq!(q, 3);

crashtracker/src/constants.rs

@@ -1,12 +1,16 @@
 // 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 2023-Present Datadog, Inc.
 
+pub const DD_CRASHTRACK_BEGIN_CONFIG: &str = "DD_CRASHTRACK_BEGIN_CONFIG";
+pub const DD_CRASHTRACK_BEGIN_COUNTERS: &str = "DD_CRASHTRACK_BEGIN_COUNTERS";
 pub const DD_CRASHTRACK_BEGIN_FILE: &str = "DD_CRASHTRACK_BEGIN_FILE";
+pub const DD_CRASHTRACK_BEGIN_METADATA: &str = "DD_CRASHTRACK_BEGIN_METADATA";
 pub const DD_CRASHTRACK_BEGIN_SIGINFO: &str = "DD_CRASHTRACK_BEGIN_SIGINFO";
 pub const DD_CRASHTRACK_BEGIN_STACKTRACE: &str = "DD_CRASHTRACK_BEGIN_STACKTRACE";
+pub const DD_CRASHTRACK_DONE: &str = "DD_CRASHTRACK_DONE";
+pub const DD_CRASHTRACK_END_CONFIG: &str = "DD_CRASHTRACK_END_CONFIG";
+pub const DD_CRASHTRACK_END_COUNTERS: &str = "DD_CRASHTRACK_END_COUNTERS";
 pub const DD_CRASHTRACK_END_FILE: &str = "DD_CRASHTRACK_END_FILE";
-pub const DD_CRASHTRACK_END_STACKTRACE: &str = "DD_CRASHTRACK_END_STACKTRACE";
+pub const DD_CRASHTRACK_END_METADATA: &str = "DD_CRASHTRACK_END_METADATA";
 pub const DD_CRASHTRACK_END_SIGINFO: &str = "DD_CRASHTRACK_END_SIGINFO";
-pub const DD_CRASHTRACK_BEGIN_COUNTERS: &str = "DD_CRASHTRACK_BEGIN_COUNTERS";
-pub const DD_CRASHTRACK_END_COUNTERS: &str = "DD_CRASHTRACK_END_COUNTERS";
-pub const DD_CRASHTRACK_DONE: &str = "DD_CRASHTRACK_DONE";
+pub const DD_CRASHTRACK_END_STACKTRACE: &str = "DD_CRASHTRACK_END_STACKTRACE";