read the instance file generated by rustkrazy_packer for hardware info

3 files changed, 26 insertions, 15 deletions

diff --git a/Cargo.lock b/Cargo.lock
index bcd0c3c..4ee2893 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -1722,6 +1722,8 @@ dependencies = [
  "fatfs",
  "fscommon",
  "reqwest",
+ "serde",
+ "serde_json",
  "squashfs-ng",
  "tempfile",
 ]
diff --git a/Cargo.toml b/Cargo.toml
index cc71be1..c7637f6 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -12,5 +12,7 @@ clap = { version = "4.2.7", features = ["derive"] }
 fatfs = "0.3.6"
 fscommon = "0.1.1"
 reqwest = { version = "0.11.17", features = ["blocking"] }
+serde = { version = "1.0", features = ["derive"] }
+serde_json = "1.0"
 squashfs-ng = "0.1.2"
 tempfile = "3.5.0"
diff --git a/src/main.rs b/src/main.rs
index c724d30..a395004 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -16,6 +16,7 @@ use clap::Parser;
 use fatfs::{FatType, FormatVolumeOptions};
 use fscommon::StreamSlice;
 use reqwest::{blocking::Client, header::CONTENT_TYPE, Url};
+use serde::{Deserialize, Serialize};
 use squashfs_ng::write::{
     Source as SqsSource, SourceData as SqsSourceData, SourceFile as SqsSourceFile,
     TreeProcessor as SqsTreeProcessor,
@@ -36,12 +37,9 @@ struct Args {
     /// Base URL of the instance, e.g. https://rustkrazy:1234@198.51.100.1
     #[arg(short = 'u', long = "update")]
     update: String,
-    /// Size of image in bytes.
-    #[arg(short = 'n', long = "size")]
-    size: u64,
-    /// Architecture of the device running the image. Supported: x86_64 rpi.
-    #[arg(short = 'a', long = "architecture")]
-    arch: String,
+    /// Location of the instance file generated by rustkrazy_packer.
+    #[arg(short = 'm', long = "instance")]
+    instance: String,
     /// Crates to install into the image.
     #[arg(short = 'c', long = "crates")]
     crates: Vec<String>,
@@ -53,6 +51,12 @@ struct Args {
     init: String,
 }
 
+#[derive(Clone, Debug, Serialize, Deserialize)]
+struct Instance {
+    size: u64,
+    arch: String,
+}
+
 fn write_mbr_partition_table(
     mbr: &mut StreamSlice<NamedTempFile>,
     dev_size: u64,
@@ -106,6 +110,15 @@ fn write_mbr_partition_table(
 }
 
 fn update_instance(args: Args) -> anyhow::Result<()> {
+    let mut file = File::open(args.instance)?;
+    let info: Instance = serde_json::from_reader(&mut file)?;
+
+    match info.arch.as_str() {
+        "x86_64" => {}
+        "rpi" => {}
+        _ => bail!("invalid architecture (supported: x86_64 rpi)"),
+    }
+
     let mut mbr_buf = Vec::new();
     let mut boot_buf = Vec::new();
     let mut root_buf = Vec::new();
@@ -122,11 +135,11 @@ fn update_instance(args: Args) -> anyhow::Result<()> {
     let mut boot = StreamSlice::new(boot_file, 0, (256 * MiB).into())?;
     let mut root = StreamSlice::new(root_file, 0, (256 * MiB).into())?;
 
-    write_mbr_partition_table(&mut mbr, args.size)?;
+    write_mbr_partition_table(&mut mbr, info.size)?;
 
-    let buf = write_boot(&mut boot, &args.arch)?;
+    let buf = write_boot(&mut boot, &info.arch)?;
     write_mbr(&mut mbr, &mut boot, &buf["vmlinuz"], &buf["cmdline.txt"])?;
-    write_root(&mut root, &args.arch, &args.crates, &args.git, &args.init)?;
+    write_root(&mut root, &info.arch, &args.crates, &args.git, &args.init)?;
 
     mbr.rewind()?;
     boot.rewind()?;
@@ -628,12 +641,6 @@ fn write_root(
 fn main() -> anyhow::Result<()> {
     let args = Args::parse();
 
-    match args.arch.as_str() {
-        "x86_64" => {}
-        "rpi" => {}
-        _ => bail!("invalid architecture (supported: x86_64 rpi)"),
-    }
-
     let init_in_crates = args.crates.iter().any(|pkg| *pkg == args.init);
     let init_in_git = args.git.iter().any(|location| {
         let mut split = location.split('%');