Add Record::parse_sample_id to parse a SampleId from a Record (#60)

Phantomical · web-flow · commit 31ae86cf200c · 2025-01-20T22:26:07.000-05:00
* Add Record::parse_sample_id to parse a SampleId from a Record
* Address clippy warning
diff --git a/perf-event/CHANGELOG.md b/perf-event/CHANGELOG.md
@@ -6,6 +6,9 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
 ## Unreleased
+### Added
+- Added `Record::parse_sample_id` to allow accessing a `SampleId` when
+  `Builder::sample_id_all` is enabled.
 
 ## 0.7.4 - 2024-05-30
 ### Added
diff --git a/perf-event/Cargo.toml b/perf-event/Cargo.toml
@@ -27,9 +27,11 @@ bitflags = "2.1"
 c-enum = "0.2.0"
 libc = "0.2"
 memmap2 = "0.9"
-perf-event-data = "0.1.1"
+perf-event-data = "0.1.8"
 perf-event-open-sys2 = "5.0.4"
 
 [dev-dependencies]
+ctrlc = "3.4.5"
 nix = { version = "0.29", features = ["process", "feature"] }
 anyhow = "1.0"
+chrono = "0.4.39"
diff --git a/perf-event/src/sampler.rs b/perf-event/src/sampler.rs
@@ -604,6 +604,32 @@ impl<'s> Record<'s> {
         let mut parser = Parser::new(self.data, self.sampler.config().clone());
         data::Record::parse_with_header(&mut parser, self.header)
     }
+
+    /// Parse the sample id for the record.
+    ///
+    /// This will only be non-empty if the [`sample_id_all`] was set when
+    /// building the counter. In addition, `MMAP` records never have a sample id
+    /// set. If you want sample ids and `MMAP` records you will need to request
+    /// `MMAP2` records instead.
+    ///
+    /// [`sample_id_all`]: crate::Builder::sample_id_all
+    pub fn parse_sample_id(&self) -> ParseResult<data::SampleId> {
+        use perf_event_open_sys::bindings;
+
+        let config = self.sampler.config();
+        let mut parser = Parser::new(self.data, config.clone());
+
+        let (mut parser, metadata) = parser.parse_metadata_with_header(self.header)?;
+
+        // All other records either already parsed the sample id or don't have it.
+        // With SAMPLE records, we can construct the sample id struct directly.
+        if self.ty() != bindings::PERF_RECORD_SAMPLE {
+            return Ok(*metadata.sample_id());
+        }
+
+        let record = parser.parse::<data::Sample>()?;
+        Ok(data::SampleId::from_sample(&record))
+    }
 }
 
 impl<'s> Drop for Record<'s> {
