From 1a1601e4d50510c9359b9ff4d101e0afd4f9bfb4 Mon Sep 17 00:00:00 2001
From: jaby <jaby@william.zone>
Date: Thu, 1 Dec 2022 04:02:38 +0100
Subject: [PATCH] Write LD file

---
 src/Tools/mkoverlay/src/creator/ldscript.rs | 55 ++++++++++++++++++---
 src/Tools/mkoverlay/src/main.rs             |  2 +-
 src/Tools/mkoverlay/src/types/mod.rs        | 12 ++---
 3 files changed, 54 insertions(+), 15 deletions(-)

diff --git a/src/Tools/mkoverlay/src/creator/ldscript.rs b/src/Tools/mkoverlay/src/creator/ldscript.rs
index bb27c2d5..4a2592fa 100644
--- a/src/Tools/mkoverlay/src/creator/ldscript.rs
+++ b/src/Tools/mkoverlay/src/creator/ldscript.rs
@@ -2,20 +2,59 @@ use super::super::types::OverlaySlot;
 use tool_helper::{Error, format_if_error, Output};
 use std::io::Write;
 
-const DEFAULT_LD_SCRIPT:&'static str = r#"
-__heap_base = __bss_end;
-"#;
+const OVERLAY_DEFAULT_START:&'static str = "__boot_loader_end"; // < will probably be "__boot_loader_start" later
 
 pub fn write(output: &mut Output, overlay_desc: &Vec<OverlaySlot>) -> Result<(), Error> {
-    if overlay_desc.is_empty() {
-        return write_default(output);
+    fn create_heap_base(overlay_desc: &Vec<OverlaySlot>) -> String {
+        let mut heap_start = format!("MAX({}, {}_end)", OVERLAY_DEFAULT_START, overlay_desc[0].name);
+
+        for slot in overlay_desc.iter().skip(1) {
+            heap_start = format!("MAX({}_end, {})", slot.name, heap_start);
+        }
+        heap_start
     }
 
-    format_if_error!(write!(output, "Dino\n"), "Writing test output failed with: {error_text}")?;
+    fn get_slot_start_adr(slot: &OverlaySlot) -> &str {
+        if let Some(slot_adr) = &slot.start_adr {
+            slot_adr.as_ref()
+        }
+
+        else {
+            OVERLAY_DEFAULT_START
+        }
+    }
+
+    if overlay_desc.is_empty() {
+        return write_heap_base(output, OVERLAY_DEFAULT_START);
+    }
+
+    write_heap_base(output, &create_heap_base(overlay_desc))?;
+    writeln!(output, "")?;
+    writeln!(output, "SECTION {{")?;
+        for slot in overlay_desc {
+            writeln!(output, "\t// {}", slot.name)?;
+            writeln!(output, "\tOVERLAY {} : NOCROSSREFS SUBALIGN(4) {{", get_slot_start_adr(slot))?;
+                for section in &slot.sections {
+                    writeln!(output, "\t\t.{} {{", section.name)?;
+                        writeln!(output, "\t\t\t__{}_start = .;", section.name)?;
+                        section.file_pattern.iter().try_for_each(|patr| writeln!(output, "\t\t\tKEEP({}(.header)", patr))?;
+                        writeln!(output, "\t\t\t__main_area_ctor = .;")?;
+
+                        for section_type in [".text.startup._GLOBAL__*", ".ctors", ".text.*", ".rodata*", ".sdata*", ".data*", ".sbss*", ".bss*"] {
+                            section.file_pattern.iter().try_for_each(|patr| writeln!(output, "\t\t\t{}({})", patr, section_type))?;
+                        }
+                    writeln!(output, "\t\t}}")?;
+                }
+            writeln!(output, "\t}}")?;
+            writeln!(output, "\t{}_end = .;", slot.name)?;
+            writeln!(output, "")?;
+        }
+    writeln!(output, "\t/DISCARD/ : {{ *(.comment*) *(.gnu.*) *(.mdebug*) *(.debug_*) *(.pdr)}}")?;
+    writeln!(output, "}}")?;
     return Ok(());
 }
 
-fn write_default(output: &mut Output) -> Result<(), Error> {
-    format_if_error!(output.write(DEFAULT_LD_SCRIPT.as_bytes()), "Writing default LD Script failed with: {error_text}")?;
+fn write_heap_base(output: &mut Output, heap_base: &str) -> Result<(), Error> {
+    format_if_error!(writeln!(output, "__heap_base = {};", heap_base), "Writing default LD Script failed with: {error_text}")?;
     Ok(())
 }
\ No newline at end of file
diff --git a/src/Tools/mkoverlay/src/main.rs b/src/Tools/mkoverlay/src/main.rs
index d33d9630..3f91e7e0 100644
--- a/src/Tools/mkoverlay/src/main.rs
+++ b/src/Tools/mkoverlay/src/main.rs
@@ -3,7 +3,7 @@ use tool_helper::{Error, open_output};
 
 fn generate_file() -> Vec<OverlaySlot> {
     let mut slots   = Vec::new();
-    let mut slot    = OverlaySlot::new("slot_0".to_owned(), String::new());
+    let mut slot    = OverlaySlot::new("slot_0".to_owned(), None);
     let mut section = OverlaySection::new("main_area".to_owned());
 
     section.add_file_pattern("bin/PSX-release/src/*.o".to_owned());
diff --git a/src/Tools/mkoverlay/src/types/mod.rs b/src/Tools/mkoverlay/src/types/mod.rs
index ed3471bc..d72cf54f 100644
--- a/src/Tools/mkoverlay/src/types/mod.rs
+++ b/src/Tools/mkoverlay/src/types/mod.rs
@@ -1,7 +1,7 @@
 #[derive(Debug)]
 pub struct OverlaySection {
-    name:         String,
-    file_pattern: Vec<String>
+    pub(super) name:         String,
+    pub(super) file_pattern: Vec<String>
 }
 
 impl OverlaySection {
@@ -16,13 +16,13 @@ impl OverlaySection {
 
 #[derive(Debug)]
 pub struct OverlaySlot {
-    name:      String,
-    start_adr: String,
-    sections:  Vec<OverlaySection>
+    pub(super) name:      String,
+    pub(super) start_adr: Option<String>,
+    pub(super) sections:  Vec<OverlaySection>
 }
 
 impl OverlaySlot {
-    pub fn new(name: String, start_adr: String) -> OverlaySlot {
+    pub fn new(name: String, start_adr: Option<String>) -> OverlaySlot {
         OverlaySlot{name, start_adr, sections: Vec::new()}
     }