Bug: 179312498

Clone this repo:
  1. 53570cf Upgrade walkdir to 2.3.3 by Jeff Vander Stoep · 10 weeks ago main master android-u-beta-1-gpl
  2. cf45515 Make walkdir available to product and vendor am: ffe6566617 by Matthew Maurer · 3 months ago
  3. ffe6566 Make walkdir available to product and vendor by Matthew Maurer · 3 months ago
  4. 170bb80 Merge "Refresh Android.bp, cargo2android.json, TEST_MAPPING." am: 935e163a3f am: a6c9e9aef6 am: fc4485b7a0 am: bf7a0a3b0f by Joel Galenson · 1 year, 6 months ago android13-d4-release android13-d4-s1-release android13-d4-s2-release android13-dev android13-frc-adbd-release android13-frc-art-release android13-frc-cellbroadcast-release android13-frc-conscrypt-release android13-frc-odp-release android13-mainline-adservices-release android13-mainline-appsearch-release android13-mainline-go-adbd-release android13-mainline-go-adservices-release android13-mainline-go-appsearch-release android13-mainline-go-media-swcodec-release android13-mainline-go-mediaprovider-release android13-mainline-go-networking-release android13-mainline-go-neuralnetworks-release android13-mainline-go-odp-release android13-mainline-go-os-statsd-release android13-mainline-go-permission-release android13-mainline-go-resolv-release android13-mainline-go-scheduling-release android13-mainline-go-sdkext-release android13-mainline-go-tethering-release android13-mainline-go-tzdata4-release android13-mainline-go-uwb-release android13-mainline-go-wifi-release android13-mainline-tzdata4-release android13-mainline-uwb-release android13-qpr1-release android13-qpr1-s1-release android13-qpr1-s2-release android13-qpr1-s3-release android13-qpr1-s4-release android13-qpr1-s5-release android13-qpr1-s6-release android13-qpr1-s7-release android13-qpr1-s8-release android13-qpr2-b-s1-release android13-qpr2-release android13-qpr2-s1-release android13-qpr2-s10-release android13-qpr2-s11-release android13-qpr2-s12-release android13-qpr2-s2-release android13-qpr2-s3-release android13-qpr2-s5-release android13-qpr2-s6-release android13-qpr2-s7-release android13-qpr2-s8-release android13-qpr2-s9-release main-16k main-16k-with-phones aml_ads_331131000 aml_ads_331418080 aml_ads_331511020 aml_ads_331611190 aml_ads_331710270 aml_ase_331011020 aml_ase_331112000 aml_go_adb_330913000 aml_go_ads_330913000 aml_go_ads_330915000 aml_go_ase_330913000 aml_go_mpr_330912000 aml_go_net_330913000 aml_go_neu_330912000 aml_go_odp_330912000 aml_go_odp_330913000 aml_go_per_330912000 aml_go_res_330912000 aml_go_sch_330911000 aml_go_sdk_330810000 aml_go_sta_330911000 aml_go_swc_330913000 aml_go_tet_330914010 aml_go_tz4_330912000 aml_go_uwb_330912000 aml_go_wif_330911000 aml_tz4_331012000 aml_tz4_331012040 aml_tz4_331012050 aml_tz4_331314010 aml_tz4_331314020 aml_tz4_331314030 aml_uwb_330810010 aml_uwb_331015040 aml_uwb_331115000 aml_uwb_331310030 aml_uwb_331410010 aml_uwb_331611010 aml_uwb_331613010 android-13.0.0_r16 android-13.0.0_r17 android-13.0.0_r18 android-13.0.0_r19 android-13.0.0_r20 android-13.0.0_r21 android-13.0.0_r22 android-13.0.0_r23 android-13.0.0_r24 android-13.0.0_r27 android-13.0.0_r28 android-13.0.0_r29 android-13.0.0_r30 android-13.0.0_r32 android-13.0.0_r33 android-13.0.0_r34 android-13.0.0_r35 android-13.0.0_r36 android-13.0.0_r37 android-13.0.0_r38 android-13.0.0_r39 android-13.0.0_r40 android-13.0.0_r41 android-13.0.0_r42 android-13.0.0_r43 android-13.0.0_r44 android-13.0.0_r45 android-13.0.0_r46 android-13.0.0_r47 android-13.0.0_r48 android-13.0.0_r49 t_frc_adb_330444000 t_frc_art_330443060 t_frc_ase_330444010 t_frc_cbr_330443000 t_frc_con_330443020 t_frc_odp_330442000 t_frc_odp_330442040
  5. bf7a0a3 Merge "Refresh Android.bp, cargo2android.json, TEST_MAPPING." am: 935e163a3f am: a6c9e9aef6 am: fc4485b7a0 by Joel Galenson · 1 year, 6 months ago

walkdir

A cross platform Rust library for efficiently walking a directory recursively. Comes with support for following symbolic links, controlling the number of open file descriptors and efficient mechanisms for pruning the entries in the directory tree.

Build status

Dual-licensed under MIT or the UNLICENSE.

Documentation

docs.rs/walkdir

Usage

To use this crate, add walkdir as a dependency to your project's Cargo.toml:

[dependencies]
walkdir = "2"

Example

The following code recursively iterates over the directory given and prints the path for each entry:

use walkdir::WalkDir;

for entry in WalkDir::new("foo") {
    let entry = entry.unwrap();
    println!("{}", entry.path().display());
}

Or, if you'd like to iterate over all entries and ignore any errors that may arise, use filter_map. (e.g., This code below will silently skip directories that the owner of the running process does not have permission to access.)

use walkdir::WalkDir;

for entry in WalkDir::new("foo").into_iter().filter_map(|e| e.ok()) {
    println!("{}", entry.path().display());
}

Example: follow symbolic links

The same code as above, except follow_links is enabled:

use walkdir::WalkDir;

for entry in WalkDir::new("foo").follow_links(true) {
    let entry = entry.unwrap();
    println!("{}", entry.path().display());
}

Example: skip hidden files and directories efficiently on unix

This uses the filter_entry iterator adapter to avoid yielding hidden files and directories efficiently:

use walkdir::{DirEntry, WalkDir};

fn is_hidden(entry: &DirEntry) -> bool {
    entry.file_name()
         .to_str()
         .map(|s| s.starts_with("."))
         .unwrap_or(false)
}

let walker = WalkDir::new("foo").into_iter();
for entry in walker.filter_entry(|e| !is_hidden(e)) {
    let entry = entry.unwrap();
    println!("{}", entry.path().display());
}

Minimum Rust version policy

This crate's minimum supported rustc version is 1.34.0.

The current policy is that the minimum Rust version required to use this crate can be increased in minor version updates. For example, if crate 1.0 requires Rust 1.20.0, then crate 1.0.z for all values of z will also require Rust 1.20.0 or newer. However, crate 1.y for y > 0 may require a newer minimum version of Rust.

In general, this crate will be conservative with respect to the minimum supported version of Rust.

Performance

The short story is that performance is comparable with find and glibc's nftw on both a warm and cold file cache. In fact, I cannot observe any performance difference after running find /, walkdir / and nftw / on my local file system (SSD, ~3 million entries). More precisely, I am reasonably confident that this crate makes as few system calls and close to as few allocations as possible.

I haven't recorded any benchmarks, but here are some things you can try with a local checkout of walkdir:

# The directory you want to recursively walk:
DIR=$HOME

# If you want to observe perf on a cold file cache, run this before *each*
# command:
sudo sh -c 'echo 3 > /proc/sys/vm/drop_caches'

# To warm the caches
find $DIR

# Test speed of `find` on warm cache:
time find $DIR

# Compile and test speed of `walkdir` crate:
cargo build --release --example walkdir
time ./target/release/examples/walkdir $DIR

# Compile and test speed of glibc's `nftw`:
gcc -O3 -o nftw ./compare/nftw.c
time ./nftw $DIR

# For shits and giggles, test speed of Python's (2 or 3) os.walk:
time python ./compare/walk.py $DIR

On my system, the performance of walkdir, find and nftw is comparable.