speed up cmdline modification at the cost of compilation time

3 files changed, 139 insertions, 24 deletions

diff --git a/Cargo.lock b/Cargo.lock
index 540b77a..bc9bafe 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -187,7 +187,7 @@ dependencies = [
  "serde_urlencoded",
  "smallvec",
  "socket2",
- "time",
+ "time 0.3.20",
  "url",
 ]
 
@@ -272,6 +272,21 @@ dependencies = [
 ]
 
 [[package]]
+name = "android-tzdata"
+version = "0.1.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e999941b234f3131b00bc13c22d06e8c5ff726d1b6318ac7eb276997bbb4fef0"
+
+[[package]]
+name = "android_system_properties"
+version = "0.1.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "819e7219dbd41043ac279b19830f2efc897156490d7fd6ea916720117ee66311"
+dependencies = [
+ "libc",
+]
+
+[[package]]
 name = "autocfg"
 version = "1.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -332,6 +347,12 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "9b1ce199063694f33ffb7dd4e0ee620741495c32833cde5aa08f02a0bf96f0c8"
 
 [[package]]
+name = "byteorder"
+version = "1.4.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "14c189c53d098945499cdfa7ecc63567cf3886b3332b312a5b4585d8d3a6a610"
+
+[[package]]
 name = "bytes"
 version = "1.4.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -362,6 +383,21 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "baf1de4339761588bc0619e3cbc0120ee582ebb74b53b4efbf79117bd2da40fd"
 
 [[package]]
+name = "chrono"
+version = "0.4.26"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ec837a71355b28f6556dbd569b37b3f363091c0bd4b2e735674521b4c5fd9bc5"
+dependencies = [
+ "android-tzdata",
+ "iana-time-zone",
+ "js-sys",
+ "num-traits",
+ "time 0.1.45",
+ "wasm-bindgen",
+ "winapi",
+]
+
+[[package]]
 name = "constant_time_eq"
 version = "0.2.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -380,11 +416,17 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "e859cd57d0710d9e06c381b550c06e76992472a8c6d527aecd2fc673dcc231fb"
 dependencies = [
  "percent-encoding",
- "time",
+ "time 0.3.20",
  "version_check",
 ]
 
 [[package]]
+name = "core-foundation-sys"
+version = "0.8.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e496a50fda8aacccc86d7529e2c1e0892dbd0f898a6b5645b5561b89c3210efa"
+
+[[package]]
 name = "cpufeatures"
 version = "0.2.7"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -445,6 +487,18 @@ dependencies = [
 ]
 
 [[package]]
+name = "fatfs"
+version = "0.3.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "05669f8e7e2d7badc545c513710f0eba09c2fbef683eb859fd79c46c355048e0"
+dependencies = [
+ "bitflags",
+ "byteorder",
+ "chrono",
+ "log",
+]
+
+[[package]]
 name = "flate2"
 version = "1.0.26"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -470,6 +524,15 @@ dependencies = [
 ]
 
 [[package]]
+name = "fscommon"
+version = "0.1.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "315ce685aca5ddcc5a3e7e436ef47d4a5d0064462849b6f0f628c28140103531"
+dependencies = [
+ "log",
+]
+
+[[package]]
 name = "futures-core"
 version = "0.3.28"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -518,7 +581,7 @@ checksum = "c85e1d9ab2eadba7e5040d4e09cbd6d072b76a557ad64e797c2cb9d4da21d7e4"
 dependencies = [
  "cfg-if",
  "libc",
- "wasi",
+ "wasi 0.11.0+wasi-snapshot-preview1",
 ]
 
 [[package]]
@@ -579,6 +642,29 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "c4a1e36c821dbe04574f602848a19f742f4fb3c98d40449f11bcad18d6b17421"
 
 [[package]]
+name = "iana-time-zone"
+version = "0.1.57"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "2fad5b825842d2b38bd206f3e81d6957625fd7f0a361e345c30e01a0ae2dd613"
+dependencies = [
+ "android_system_properties",
+ "core-foundation-sys",
+ "iana-time-zone-haiku",
+ "js-sys",
+ "wasm-bindgen",
+ "windows",
+]
+
+[[package]]
+name = "iana-time-zone-haiku"
+version = "0.1.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f31827a206f56af32e590ba56d5d2d085f558508192593743f16b2306495269f"
+dependencies = [
+ "cc",
+]
+
+[[package]]
 name = "idna"
 version = "0.3.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -709,7 +795,7 @@ checksum = "5b9d9a46eff5b4ff64b45a9e316a6d1e0bc719ef429cbec4dc630684212bfdf9"
 dependencies = [
  "libc",
  "log",
- "wasi",
+ "wasi 0.11.0+wasi-snapshot-preview1",
  "windows-sys 0.45.0",
 ]
 
@@ -728,6 +814,15 @@ dependencies = [
 ]
 
 [[package]]
+name = "num-traits"
+version = "0.2.16"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f30b0abd723be7e2ffca1272140fac1a2f084c77ec3e123c192b66af1ee9e6c2"
+dependencies = [
+ "autocfg",
+]
+
+[[package]]
 name = "num_cpus"
 version = "1.15.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -907,6 +1002,8 @@ dependencies = [
  "actix-web",
  "actix-web-httpauth",
  "constant_time_eq",
+ "fatfs",
+ "fscommon",
  "nix",
  "rustls",
  "rustls-pemfile",
@@ -1107,6 +1204,17 @@ dependencies = [
 
 [[package]]
 name = "time"
+version = "0.1.45"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1b797afad3f312d1c66a56d11d0316f916356d11bd158fbc6ca6389ff6bf805a"
+dependencies = [
+ "libc",
+ "wasi 0.10.0+wasi-snapshot-preview1",
+ "winapi",
+]
+
+[[package]]
+name = "time"
 version = "0.3.20"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "cd0cbfecb4d19b5ea75bb31ad904eb5b9fa13f21079c3b92017ebdf4999a5890"
@@ -1262,6 +1370,12 @@ checksum = "49874b5167b65d7193b8aba1567f5c7d93d001cafc34600cee003eda787e483f"
 
 [[package]]
 name = "wasi"
+version = "0.10.0+wasi-snapshot-preview1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1a143597ca7c7793eff794def352d41792a93c481eb1042423ff7ff72ba2c31f"
+
+[[package]]
+name = "wasi"
 version = "0.11.0+wasi-snapshot-preview1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "9c8d87e72b64a3b4db28d11ce29237c246188f4f51057d65a7eab63b7987e423"
@@ -1372,6 +1486,15 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "712e227841d057c1ee1cd2fb22fa7e5a5461ae8e48fa2ca79ec42cfc1931183f"
 
 [[package]]
+name = "windows"
+version = "0.48.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e686886bc078bc1b0b600cac0147aadb815089b6e4da64016cbd754b6342700f"
+dependencies = [
+ "windows-targets 0.48.0",
+]
+
+[[package]]
 name = "windows-sys"
 version = "0.45.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
diff --git a/Cargo.toml b/Cargo.toml
index b180fd6..a7669ea 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -9,6 +9,8 @@ edition = "2021"
 actix-web = { version = "4.3.1", features = ["rustls"] }
 actix-web-httpauth = "0.8.0"
 constant_time_eq = "0.2.5"
+fatfs = "0.3.6"
+fscommon = "0.1.1"
 nix = "0.26.2"
 rustls = "0.20.0"
 rustls-pemfile = "1.0.2"
diff --git a/src/main.rs b/src/main.rs
index 89db44c..2aa21c8 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -1,7 +1,7 @@
 use rustkrazy_admind::{Error, Result};
 
 use std::fs::{self, File};
-use std::io::{self, BufReader, Write};
+use std::io::{self, BufReader, Read, Write};
 
 use actix_web::{
     dev::ServiceRequest, http::header::ContentType, web, App, HttpResponse, HttpServer,
@@ -10,6 +10,7 @@ use actix_web_httpauth::extractors::basic::{BasicAuth, Config};
 use actix_web_httpauth::extractors::AuthenticationError;
 use actix_web_httpauth::middleware::HttpAuthentication;
 use constant_time_eq::constant_time_eq;
+use fscommon::BufStream;
 use nix::sys::reboot::{reboot, RebootMode};
 use rustls::{Certificate, PrivateKey, ServerConfig};
 use rustls_pemfile::{certs, pkcs8_private_keys};
@@ -261,28 +262,17 @@ fn validate_credentials(user_id: &str, user_password: &str) -> io::Result<bool>
     ))
 }
 
-fn replace_slice<T>(src: &mut [T], old: &[T], new: &[T])
-where
-    T: Clone + PartialEq,
-{
-    let iteration = if src.starts_with(old) {
-        src[..old.len()].clone_from_slice(new);
-        old.len()
-    } else {
-        1
-    };
-
-    if src.len() > old.len() {
-        replace_slice(&mut src[iteration..], old, new);
-    }
-}
-
 fn modify_cmdline(old: &str, new: &str) -> Result<()> {
     let boot = boot_dev()?;
+    let boot_partition = File::open(boot)?;
+    let buf_stream = BufStream::new(boot_partition);
+    let bootfs = fatfs::FileSystem::new(buf_stream, fatfs::FsOptions::new())?;
+
+    let mut file = bootfs.root_dir().open_file("cmdline.txt")?;
 
-    let mut cmdline = fs::read(boot)?;
-    replace_slice(&mut cmdline, old.as_bytes(), new.as_bytes());
-    fs::write(boot, cmdline)?;
+    let mut cmdline = String::new();
+    file.read_to_string(&mut cmdline)?;
+    file.write_all(cmdline.replace(old, new).as_bytes())?;
 
     nix::unistd::sync();
     Ok(())