From 16c3395524d59b4fdcf8dbb288eaac7635605940 Mon Sep 17 00:00:00 2001
From: Gwilym Inzani <gw@ilym.me>
Date: Thu, 6 Apr 2023 21:09:44 +0100
Subject: [PATCH] Really basic elf parser

---
 agb-gbafix/.gitignore  |  1 +
 agb-gbafix/Cargo.lock  | 16 ++++++++++++++
 agb-gbafix/Cargo.toml  |  9 ++++++++
 agb-gbafix/src/main.rs | 47 ++++++++++++++++++++++++++++++++++++++++++
 4 files changed, 73 insertions(+)
 create mode 100644 agb-gbafix/.gitignore
 create mode 100644 agb-gbafix/Cargo.lock
 create mode 100644 agb-gbafix/Cargo.toml
 create mode 100644 agb-gbafix/src/main.rs

diff --git a/agb-gbafix/.gitignore b/agb-gbafix/.gitignore
new file mode 100644
index 00000000..0b512c76
--- /dev/null
+++ b/agb-gbafix/.gitignore
@@ -0,0 +1 @@
+!Cargo.lock
\ No newline at end of file
diff --git a/agb-gbafix/Cargo.lock b/agb-gbafix/Cargo.lock
new file mode 100644
index 00000000..4677f650
--- /dev/null
+++ b/agb-gbafix/Cargo.lock
@@ -0,0 +1,16 @@
+# This file is automatically @generated by Cargo.
+# It is not intended for manual editing.
+version = 3
+
+[[package]]
+name = "agb-gbafix"
+version = "0.1.0"
+dependencies = [
+ "elf",
+]
+
+[[package]]
+name = "elf"
+version = "0.7.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e2b183d6ce6ca4cf30e3db37abf5b52568b5f9015c97d9fbdd7026aa5dcdd758"
diff --git a/agb-gbafix/Cargo.toml b/agb-gbafix/Cargo.toml
new file mode 100644
index 00000000..ee86b776
--- /dev/null
+++ b/agb-gbafix/Cargo.toml
@@ -0,0 +1,9 @@
+[package]
+name = "agb-gbafix"
+version = "0.1.0"
+edition = "2021"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+elf = "0.7"
\ No newline at end of file
diff --git a/agb-gbafix/src/main.rs b/agb-gbafix/src/main.rs
new file mode 100644
index 00000000..e3c0d3a4
--- /dev/null
+++ b/agb-gbafix/src/main.rs
@@ -0,0 +1,47 @@
+use std::{
+    fs,
+    io::{self, Write},
+    path::PathBuf,
+};
+
+fn main() -> Result<(), Box<dyn std::error::Error>> {
+    let path = PathBuf::from("tests/text_render");
+    let file_data = fs::read(path)?;
+    let file_data = file_data.as_slice();
+
+    let elf_file = elf::ElfBytes::<elf::endian::AnyEndian>::minimal_parse(file_data)?;
+
+    let (section_headers, strtab) = elf_file.section_headers_with_strtab()?;
+    let section_headers = section_headers.expect("Expected section headers");
+    let strtab = strtab.expect("Expected string table");
+
+    let output = fs::File::create("out.gba")?;
+    let mut buf_writer = io::BufWriter::new(output);
+
+    for section_header in section_headers.iter() {
+        let section_name = strtab.get(section_header.sh_name as usize)?;
+
+        const SHT_NOBITS: u32 = 8;
+        const SHT_NULL: u32 = 0;
+        const SHF_ALLOC: u64 = 2;
+
+        if (section_header.sh_type == SHT_NOBITS || section_header.sh_type == SHT_NULL)
+            || section_header.sh_flags & SHF_ALLOC == 0
+        {
+            continue;
+        }
+
+        println!("{section_name}");
+
+        let (data, compression) = elf_file.section_data(&section_header)?;
+        if let Some(compression) = compression {
+            panic!("Cannot compress elf content, but got compression header {compression:?}");
+        }
+
+        buf_writer.write_all(data)?;
+    }
+
+    buf_writer.flush()?;
+
+    Ok(())
+}