samply 0.13.1

A command line profiler for macOS and Linux.
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use std::ffi::OsStr;
use std::fs::File;
use std::io::BufWriter;
use std::path::Path;

use flate2::{Compression, GzBuilder};
use fxprof_processed_profile::Profile;

// Level two has an acceptable trade-off between how long compression
// takes and how much data it saves on the profile JSONs I tested with.
const GZIP_COMPRESSION_LEVEL: u32 = 2;

pub fn save_profile_to_file(profile: &Profile, output_path: &Path) -> std::io::Result<()> {
    let output_file = match File::create(output_path) {
        Ok(output_file) => output_file,
        Err(err) => {
            eprintln!("Couldn't create output file {:?}: {}", output_path, err);
            std::process::exit(1);
        }
    };

    let writer = BufWriter::new(output_file);
    let is_gz = output_path.extension() == Some(OsStr::new("gz"));
    if is_gz {
        let name_without_gz = output_path.file_stem().unwrap().to_string_lossy();
        let builder = GzBuilder::new().filename(name_without_gz.as_bytes());
        let gz = builder.write(writer, Compression::new(GZIP_COMPRESSION_LEVEL));
        let gz = BufWriter::new(gz);
        serde_json::to_writer(gz, &profile)?;
    } else {
        serde_json::to_writer(writer, &profile)?;
    }
    Ok(())
}