5 files changed, 82 insertions, 10 deletions
diff --git a/profcollectd/libprofcollectd/Android.bp b/profcollectd/libprofcollectd/Android.bp
index 2e37af9e..7fb1b567 100644
--- a/profcollectd/libprofcollectd/Android.bp
+++ b/profcollectd/libprofcollectd/Android.bp
@@ -60,4 +60,7 @@ rust_library {
         "libsimpleperf_profcollect_rust",
     ],
     shared_libs: ["libsimpleperf_profcollect"],
+
+    // Enable 'test' feature for more verbose logging and the logging trace provider.
+    // features: ["test"],
 }
diff --git a/profcollectd/libprofcollectd/lib.rs b/profcollectd/libprofcollectd/lib.rs
index aacbf8e3..f417bd8c 100644
--- a/profcollectd/libprofcollectd/lib.rs
+++ b/profcollectd/libprofcollectd/lib.rs
@@ -23,6 +23,9 @@ mod service;
 mod simpleperf_etm_trace_provider;
 mod trace_provider;
 
+#[cfg(feature = "test")]
+mod logging_trace_provider;
+
 use anyhow::{Context, Result};
 use profcollectd_aidl_interface::aidl::com::android::server::profcollect::IProfCollectd::{
     self, BnProfCollectd,
@@ -90,9 +93,8 @@ pub fn report() -> Result<String> {
 
 /// Inits logging for Android
 pub fn init_logging() {
+    let min_log_level = if cfg!(feature = "test") { log::Level::Info } else { log::Level::Error };
     android_logger::init_once(
-        android_logger::Config::default()
-            .with_tag("profcollectd")
-            .with_min_level(log::Level::Error),
+        android_logger::Config::default().with_tag("profcollectd").with_min_level(min_log_level),
     );
 }
diff --git a/profcollectd/libprofcollectd/logging_trace_provider.rs b/profcollectd/libprofcollectd/logging_trace_provider.rs
new file mode 100644
index 00000000..1325855d
--- /dev/null
+++ b/profcollectd/libprofcollectd/logging_trace_provider.rs
@@ -0,0 +1,56 @@
+//
+// Copyright (C) 2021 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+//! Logging trace provider for development and testing purposes.
+
+use anyhow::Result;
+use std::path::Path;
+use std::time::Duration;
+use trace_provider::TraceProvider;
+
+use crate::trace_provider;
+
+static LOGGING_TRACEFILE_EXTENSION: &str = "loggingtrace";
+
+pub struct LoggingTraceProvider {}
+
+impl TraceProvider for LoggingTraceProvider {
+    fn get_name(&self) -> &'static str {
+        "logging"
+    }
+
+    fn trace(&self, trace_dir: &Path, tag: &str, sampling_period: &Duration) {
+        let trace_file = trace_provider::get_path(trace_dir, tag, LOGGING_TRACEFILE_EXTENSION);
+
+        log::info!(
+            "Trace event triggered, tag {}, sampling for {}ms, saving to {}",
+            tag,
+            sampling_period.as_millis(),
+            trace_file.display()
+        );
+    }
+
+    fn process(&self, _trace_dir: &Path, _profile_dir: &Path) -> Result<()> {
+        log::info!("Process event triggered");
+        Ok(())
+    }
+}
+
+impl LoggingTraceProvider {
+    pub fn supported() -> bool {
+        true
+    }
+}
diff --git a/profcollectd/libprofcollectd/simpleperf_etm_trace_provider.rs b/profcollectd/libprofcollectd/simpleperf_etm_trace_provider.rs
index 2038a5be..d3baaa36 100644
--- a/profcollectd/libprofcollectd/simpleperf_etm_trace_provider.rs
+++ b/profcollectd/libprofcollectd/simpleperf_etm_trace_provider.rs
@@ -35,12 +35,10 @@ impl TraceProvider for SimpleperfEtmTraceProvider {
     }
 
     fn trace(&self, trace_dir: &Path, tag: &str, sampling_period: &Duration) {
-        let mut trace_file = PathBuf::from(trace_dir);
-        trace_file.push(trace_provider::construct_file_name(tag));
-        trace_file.set_extension(ETM_TRACEFILE_EXTENSION);
+        let trace_file = trace_provider::get_path(trace_dir, tag, ETM_TRACEFILE_EXTENSION);
 
         simpleperf_profcollect::record(
-            &trace_file,
+            &*trace_file,
             sampling_period,
             simpleperf_profcollect::RecordScope::BOTH,
         );
diff --git a/profcollectd/libprofcollectd/trace_provider.rs b/profcollectd/libprofcollectd/trace_provider.rs
index ed0d56f5..44d4cee9 100644
--- a/profcollectd/libprofcollectd/trace_provider.rs
+++ b/profcollectd/libprofcollectd/trace_provider.rs
@@ -18,12 +18,15 @@
 
 use anyhow::{anyhow, Result};
 use chrono::Utc;
-use std::path::Path;
+use std::path::{Path, PathBuf};
 use std::sync::{Arc, Mutex};
 use std::time::Duration;
 
 use crate::simpleperf_etm_trace_provider::SimpleperfEtmTraceProvider;
 
+#[cfg(feature = "test")]
+use crate::logging_trace_provider::LoggingTraceProvider;
+
 pub trait TraceProvider {
     fn get_name(&self) -> &'static str;
     fn trace(&self, trace_dir: &Path, tag: &str, sampling_period: &Duration);
@@ -36,9 +39,19 @@ pub fn get_trace_provider() -> Result<Arc<Mutex<dyn TraceProvider + Send>>> {
         return Ok(Arc::new(Mutex::new(SimpleperfEtmTraceProvider {})));
     }
 
+    #[cfg(feature = "test")]
+    if LoggingTraceProvider::supported() {
+        log::info!("logging trace provider registered.");
+        return Ok(Arc::new(Mutex::new(LoggingTraceProvider {})));
+    }
+
     Err(anyhow!("No trace provider found for this device."))
 }
 
-pub fn construct_file_name(tag: &str) -> String {
-    format!("{}_{}", Utc::now().format("%Y%m%d-%H%M%S"), tag)
+pub fn get_path(dir: &Path, tag: &str, ext: &str) -> Box<Path> {
+    let filename = format!("{}_{}", Utc::now().format("%Y%m%d-%H%M%S"), tag);
+    let mut trace_file = PathBuf::from(dir);
+    trace_file.push(filename);
+    trace_file.set_extension(ext);
+    trace_file.into_boxed_path()
 }