refactor things around

build.zig

@@ -4,15 +4,6 @@ pub fn build(b: *std.Build) void {
     const target = b.standardTargetOptions(.{});
     const optimize = b.standardOptimizeOption(.{});
 
-    const dolLib = b.addStaticLibrary(.{
-        .name = "elphin",
-        .root_source_file = b.path("src/dol.zig"),
-        .target = target,
-        .optimize = optimize,
-    });
-
-    b.installArtifact(dolLib);
-
     const exe = b.addExecutable(.{
         .name = "elphin",
         .root_source_file = b.path("src/main.zig"),

src/dol.zig

@@ -0,0 +1,128 @@
+const std = @import("std");
+const elf = @import("elf.zig");
+const oldzig = @import("oldzig.zig");
+
+pub const MaximumTextSegments = 7;
+pub const MaximumDataSegments = 11;
+
+pub const DolHeader = extern struct {
+    textOffsets: [7]u32,
+    dataOffsets: [11]u32,
+    textAddress: [7]u32,
+    dataAddress: [11]u32,
+    textSize: [7]u32,
+    dataSize: [11]u32,
+    BSSAddress: u32,
+    BSSSize: u32,
+    entrypoint: u32,
+    reserved: [7]u32,
+};
+
+pub const DolMap = struct {
+    header: DolHeader,
+    textCount: u32,
+    dataCount: u32,
+    originalFileTextOffset: [7]u32,
+    originalFileDataOffset: [11]u32,
+};
+
+const DOLAlignment = 64;
+pub fn createDOLMapping(segments: elf.ELFSegments) DolMap {
+    // Create dol map
+    var dolMap = DolMap{
+        .header = .{
+            .textOffsets = .{0} ** 7,
+            .dataOffsets = .{0} ** 11,
+            .textAddress = .{0} ** 7,
+            .dataAddress = .{0} ** 11,
+            .textSize = .{0} ** 7,
+            .dataSize = .{0} ** 11,
+            .BSSAddress = segments.bssAddress,
+            .BSSSize = segments.bssSize,
+            .entrypoint = segments.entryPoint,
+            .reserved = .{0} ** 7,
+        },
+        .textCount = segments.textCount,
+        .dataCount = segments.dataCount,
+        .originalFileTextOffset = undefined,
+        .originalFileDataOffset = undefined,
+    };
+
+    // Setup dummy segments if no TEXT or DATA segments are present
+    dolMap.header.textOffsets[0] = std.mem.alignForward(u32, @sizeOf(DolHeader), DOLAlignment);
+    dolMap.header.dataOffsets[0] = std.mem.alignForward(u32, @sizeOf(DolHeader), DOLAlignment);
+
+    var currentPosition = std.mem.alignForward(u32, @sizeOf(DolHeader), DOLAlignment);
+
+    for (0..segments.textCount) |i| {
+        // Set offset to aligned address
+        dolMap.header.textOffsets[i] = currentPosition;
+
+        // Copy over text segment info
+        dolMap.originalFileTextOffset[i] = segments.text[i].offset;
+        dolMap.header.textAddress[i] = segments.text[i].address;
+        dolMap.header.textSize[i] = segments.text[i].size;
+
+        // Get next aligned position
+        currentPosition = std.mem.alignForward(u32, currentPosition + dolMap.header.textSize[i], DOLAlignment);
+    }
+
+    for (0..segments.dataCount) |i| {
+        // Set offset to aligned address
+        dolMap.header.dataOffsets[i] = currentPosition;
+
+        // Copy over text segment info
+        dolMap.originalFileDataOffset[i] = segments.data[i].offset;
+        dolMap.header.dataAddress[i] = segments.data[i].address;
+        dolMap.header.dataSize[i] = segments.data[i].size;
+
+        // Get next aligned position
+        currentPosition = std.mem.alignForward(u32, currentPosition + dolMap.header.dataSize[i], DOLAlignment);
+    }
+
+    return dolMap;
+}
+
+pub fn writeDOL(map: DolMap, input: std.fs.File, output: std.fs.File) !void {
+    const reader = input.reader();
+    const writer = output.writer();
+
+    // Write header
+    try oldzig.writeStructEndian(writer, map.header, std.builtin.Endian.big);
+
+    // Create buffer for pump
+    var fifo = std.fifo.LinearFifo(u8, .{ .Static = 1024 * 1024 }).init();
+    defer fifo.deinit();
+
+    // Copy over text segments
+    for (0..map.textCount) |i| {
+        // Seek to text segment
+        try input.seekTo(map.originalFileTextOffset[i]);
+
+        // Create limited reader to segment size
+        var limitedReader = std.io.limitedReader(reader, map.header.textSize[i]);
+
+        // Seek to destination
+        try output.seekTo(map.header.textOffsets[i]);
+
+        // Copy segment
+        std.log.debug("Copying text segment {d} at 0x{x} -> 0x{x}", .{ i, map.header.textAddress[i], map.header.textOffsets[i] });
+        try fifo.pump(&limitedReader, writer);
+    }
+
+    // Copy over data segments
+    for (0..map.dataCount) |i| {
+        // Seek to data segment
+        try input.seekTo(map.originalFileDataOffset[i]);
+
+        // Create limited reader to segment size
+        var limitedReader = std.io.limitedReader(reader, map.header.dataSize[i]);
+
+        // Seek to destination
+        try output.seekTo(map.header.dataOffsets[i]);
+
+        // Copy segment
+        std.log.debug("Copying data segment {d} at 0x{x} -> 0x{x}", .{ i, map.header.dataAddress[i], map.header.dataOffsets[i] });
+        try fifo.pump(&limitedReader, writer);
+    }
+}

src/elf.zig

@@ -1,5 +1,5 @@
 const std = @import("std");
-const oldzig = @import("oldzig.zig");
+const dol = @import("dol.zig");
 
 // Cool website for ELF info:
 // https://www.man7.org/linux/man-pages/man5/elf.5.html
@@ -27,9 +27,6 @@ const ELFVersion_Current = 1;
 const ELFType_Executable = 2;
 const ELFMachine_PowerPC = 20;
 
-const MaximumTextSegments = 7;
-const MaximumDataSegments = 11;
-
 const PSFlags_Executable = 1;
 const PSFlags_Writable = 2;
 const PSFlags_Readable = 4;
@@ -62,51 +59,36 @@ const ELFProgramHeader = extern struct {
     p_align: u32,
 };
 
-pub const DolHeader = extern struct {
-    text_off: [7]u32,
-    data_off: [11]u32,
-    text_addr: [7]u32,
-    data_addr: [11]u32,
-    text_size: [7]u32,
-    data_size: [11]u32,
-    bss_addr: u32,
-    bss_size: u32,
-    entry: u32,
-    pad: [7]u32,
-};
-
-pub const DolMap = struct {
-    header: DolHeader,
-    text_cnt: u32,
-    data_cnt: u32,
-    text_elf_off: [7]u32,
-    data_elf_off: [11]u32,
-    flags: u32,
-};
-
 const DolHasBSS = 1;
 
-pub fn readELF(file: std.fs.File) !DolMap {
+pub const SegmentInfo = struct {
+    offset: u32,
+    size: u32,
+    address: u32,
+};
 
-    // Create dol map
+pub const ELFSegments = struct {
-    var dolMap = DolMap{
+    entryPoint: u32,
-        .header = .{
+    textCount: u4,
-            .text_off = .{0} ** 7,
+    text: [dol.MaximumTextSegments]SegmentInfo,
-            .data_off = .{0} ** 11,
+    dataCount: u4,
-            .text_addr = .{0} ** 7,
+    data: [dol.MaximumDataSegments]SegmentInfo,
-            .data_addr = .{0} ** 11,
+    hasBSS: bool,
-            .text_size = .{0} ** 7,
+    bssAddress: u32,
-            .data_size = .{0} ** 11,
+    bssSize: u32,
-            .bss_addr = 0,
+};
-            .bss_size = 0,
+
-            .entry = 0,
+pub fn readELF(file: std.fs.File) !ELFSegments {
-            .pad = .{0} ** 7,
+    // Create segment map
-        },
+    var elfMap: ELFSegments = .{
-        .text_cnt = 0,
+        .entryPoint = undefined,
-        .data_cnt = 0,
+        .textCount = 0,
-        .text_elf_off = undefined,
+        .text = undefined,
-        .data_elf_off = undefined,
+        .dataCount = 0,
-        .flags = 0,
+        .data = undefined,
+        .hasBSS = false,
+        .bssAddress = 0,
+        .bssSize = 0,
     };
 
     // Read header
@@ -116,14 +98,14 @@ pub fn readELF(file: std.fs.File) !DolMap {
     try checkELFHeader(header);
 
     // Get entry point
-    dolMap.header.entry = header.e_entry;
+    elfMap.entryPoint = header.e_entry;
 
     // Read program headers
-    const phnum = header.e_phnum;
+    const programCount = header.e_phnum;
-    const phoff = header.e_phoff;
+    const programOffset = header.e_phoff;
 
     // Sanity checks
-    if (phnum == 0 or phoff == 0) {
+    if (programCount == 0 or programOffset == 0) {
         return ELFError.MissingProgramHeader;
     }
     if (header.e_phentsize != @sizeOf(ELFProgramHeader)) {
@@ -131,38 +113,38 @@ pub fn readELF(file: std.fs.File) !DolMap {
     }
 
     // Read program headers
-    try file.seekTo(phoff);
+    try file.seekTo(programOffset);
 
-    for (0..phnum) |_| {
+    for (0..programCount) |_| {
         const programHeader = try reader.readStructEndian(ELFProgramHeader, std.builtin.Endian.big);
 
         // Skip non-loadable segments
         if (programHeader.p_type != 1) {
-            std.debug.print("Skipping non-loadable segment at 0x{x}\n", .{programHeader.p_vaddr});
+            std.log.debug("Skipping non-loadable segment at 0x{x}", .{programHeader.p_vaddr});
             continue;
         }
 
         // Skip empty segments
         if (programHeader.p_memsz == 0) {
-            std.debug.print("Skipping empty segment at 0x{x}\n", .{programHeader.p_vaddr});
+            std.log.debug("Skipping empty segment at 0x{x}", .{programHeader.p_vaddr});
             continue;
         }
 
         // Check if segment is readable
         if (programHeader.p_flags & PSFlags_Readable == 0) {
-            std.debug.print("Warning: non-readable segment at 0x{x}\n", .{programHeader.p_vaddr});
+            std.log.debug("Warning: non-readable segment at 0x{x}", .{programHeader.p_vaddr});
         }
 
         // If the segment is executable, it's a TEXT segment
         if (programHeader.p_flags & PSFlags_Executable != 0) {
             // Do we have too many text segments?
-            if (dolMap.text_cnt >= MaximumTextSegments) {
+            if (elfMap.textCount >= dol.MaximumTextSegments) {
                 return ELFError.TooManyTextSegments;
             }
 
             // Check if segment is writable
             if (programHeader.p_flags & PSFlags_Writable != 0) {
-                std.debug.print("Warning: segment at 0x{x} is both executable and writable\n", .{programHeader.p_vaddr});
+                std.log.debug("Warning: segment at 0x{x} is both executable and writable", .{programHeader.p_vaddr});
             }
 
             // Check if segment has valid memory size
@@ -173,129 +155,63 @@ pub fn readELF(file: std.fs.File) !DolMap {
             // Check if there's leftover space
             if (programHeader.p_filesz < programHeader.p_memsz) {
                 // Add as BSS segment of whatever is left between the file and memory sizes
-                // TODO: why?!
+                addOrExtendBSS(&elfMap, programHeader.p_paddr + programHeader.p_filesz, programHeader.p_memsz - programHeader.p_filesz);
-                add_bss(&dolMap, programHeader.p_paddr + programHeader.p_filesz, programHeader.p_memsz - programHeader.p_filesz);
+                std.log.debug("Found bss segment (TEXT) at 0x{x}", .{programHeader.p_paddr + programHeader.p_filesz});
-                std.debug.print("Found bss segment (TEXT) at 0x{x}\n", .{programHeader.p_paddr + programHeader.p_filesz});
             }
 
-            std.debug.print("Found text segment at 0x{x}\n", .{programHeader.p_vaddr});
+            std.log.debug("Found text segment at 0x{x}", .{programHeader.p_vaddr});
 
-            dolMap.header.text_addr[dolMap.text_cnt] = programHeader.p_paddr;
+            elfMap.text[elfMap.textCount] = .{
-            dolMap.header.text_size[dolMap.text_cnt] = programHeader.p_filesz;
+                .address = programHeader.p_paddr,
-            dolMap.text_elf_off[dolMap.text_cnt] = programHeader.p_offset;
+                .size = programHeader.p_filesz,
+                .offset = programHeader.p_offset,
+            };
 
-            dolMap.text_cnt += 1;
+            elfMap.textCount += 1;
         } else {
             // DATA or BSS segment
 
             // TODO: ????
             if (programHeader.p_filesz == 0) {
-                add_bss(&dolMap, programHeader.p_paddr, programHeader.p_memsz);
+                addOrExtendBSS(&elfMap, programHeader.p_paddr, programHeader.p_memsz);
-                std.debug.print("Found bss segment (DATA) at 0x{x}\n", .{programHeader.p_vaddr});
+                std.log.debug("Found bss segment (DATA) at 0x{x}", .{programHeader.p_vaddr});
                 continue;
             }
 
             // Do we have too many data segments?
-            if (dolMap.data_cnt >= MaximumDataSegments) {
+            if (elfMap.dataCount >= dol.MaximumDataSegments) {
                 return ELFError.TooManyDataSegments;
             }
 
-            std.debug.print("Found data segment at 0x{x}\n", .{programHeader.p_vaddr});
+            std.log.debug("Found data segment at 0x{x}", .{programHeader.p_vaddr});
 
-            dolMap.header.data_addr[dolMap.data_cnt] = programHeader.p_paddr;
+            elfMap.data[elfMap.dataCount] = .{
-            dolMap.header.data_size[dolMap.data_cnt] = programHeader.p_filesz;
+                .address = programHeader.p_paddr,
-            dolMap.data_elf_off[dolMap.data_cnt] = programHeader.p_offset;
+                .size = programHeader.p_filesz,
+                .offset = programHeader.p_offset,
+            };
 
-            dolMap.data_cnt += 1;
+            elfMap.dataCount += 1;
         }
     }
 
-    return dolMap;
+    return elfMap;
 }
 
-// I don't understand what this does
+fn addOrExtendBSS(map: *ELFSegments, addr: u32, size: u32) void {
-fn add_bss(map: *DolMap, addr: u32, size: u32) void {
+    // If we already have a BSS segment and it lines up, extend it
-    if (map.flags & DolHasBSS != 0) {
+    if (map.hasBSS) {
-        const originalAddr = map.header.bss_addr;
+        const originalAddr = map.bssAddress;
-        const originalSize = map.header.bss_size;
+        const originalSize = map.bssSize;
         if ((originalAddr + originalSize) == addr) {
-            map.header.bss_size = originalSize + size;
+            map.bssSize = originalSize + size;
-        }
-    } else {
-        map.header.bss_addr = addr;
-        map.header.bss_size = size;
-        map.flags |= DolHasBSS;
         }
+        return;
     }
 
-const DOLAlignment = 64;
+    map.bssAddress = addr;
-pub fn alignSegments(map: *DolMap) void {
+    map.bssSize = size;
-    std.debug.print("Mapping DOL to 64 byte alignment\n", .{});
+    map.hasBSS = true;
-    var currentPosition = std.mem.alignForward(u32, @sizeOf(DolHeader), DOLAlignment);
-
-    for (0..map.text_cnt) |i| {
-        std.debug.print(" - Mapping text segment {d} at 0x{x} -> 0x{x}\n", .{ i, map.header.text_addr[i], currentPosition });
-        map.header.text_off[i] = currentPosition;
-        currentPosition = std.mem.alignForward(u32, currentPosition + map.header.text_size[i], DOLAlignment);
-    }
-
-    for (0..map.data_cnt) |i| {
-        std.debug.print(" - Mapping data segment {d} at 0x{x} -> 0x{x}\n", .{ i, map.header.data_addr[i], currentPosition });
-        map.header.data_off[i] = currentPosition;
-        currentPosition = std.mem.alignForward(u32, currentPosition + map.header.data_size[i], DOLAlignment);
-    }
-
-    // Add dummy segments if no TEXT or DATA segments are present
-    if (map.text_cnt == 0) {
-        map.header.text_off[0] = std.mem.alignForward(u32, @sizeOf(DolHeader), DOLAlignment);
-    }
-    if (map.data_cnt == 0) {
-        map.header.data_off[0] = std.mem.alignForward(u32, @sizeOf(DolHeader), DOLAlignment);
-    }
-}
-
-pub fn writeDOL(map: DolMap, input: std.fs.File, output: std.fs.File) !void {
-    const reader = input.reader();
-    const writer = output.writer();
-
-    // Write header
-    try oldzig.writeStructEndian(writer, map.header, std.builtin.Endian.big);
-
-    // Create buffer for pump
-    var fifo = std.fifo.LinearFifo(u8, .{ .Static = 1024 * 1024 }).init();
-    defer fifo.deinit();
-
-    // Copy over text segments
-    for (0..map.text_cnt) |i| {
-        // Seek to text segment
-        try input.seekTo(map.text_elf_off[i]);
-
-        // Create limited reader to segment size
-        var limitedReader = std.io.limitedReader(reader, map.header.text_size[i]);
-
-        // Seek to destination
-        try output.seekTo(map.header.text_off[i]);
-
-        // Copy segment
-        std.debug.print("Copying text segment {d} at 0x{x} -> 0x{x}\n", .{ i, map.header.text_addr[i], map.header.text_off[i] });
-        try fifo.pump(&limitedReader, writer);
-    }
-
-    // Copy over data segments
-    for (0..map.data_cnt) |i| {
-        // Seek to data segment
-        try input.seekTo(map.data_elf_off[i]);
-
-        // Create limited reader to segment size
-        var limitedReader = std.io.limitedReader(reader, map.header.data_size[i]);
-
-        // Seek to destination
-        try output.seekTo(map.header.data_off[i]);
-
-        // Copy segment
-        std.debug.print("Copying data segment {d} at 0x{x} -> 0x{x}\n", .{ i, map.header.data_addr[i], map.header.data_off[i] });
-        try fifo.pump(&limitedReader, writer);
-    }
 }
 
 fn checkELFHeader(header: ELFHeader) !void {

src/main.zig

@@ -1,5 +1,6 @@
 const std = @import("std");
 const elf = @import("elf.zig");
+const dol = @import("dol.zig");
 
 pub fn main() !void {
     // Get allocator
@@ -12,7 +13,7 @@ pub fn main() !void {
     defer std.process.argsFree(allocator, args);
 
     if (args.len < 3) {
-        std.debug.print("Usage: {s} <input.elf> <output.dol>\n", .{args[0]});
+        std.log.err("Usage: {s} <input.elf> <output.dol>", .{args[0]});
         std.process.exit(1);
     }
 
@@ -22,13 +23,13 @@ pub fn main() !void {
     // Read input
     const input = try std.fs.cwd().openFile(inputPath, .{});
     defer input.close();
-    var map = try elf.readELF(input);
+    const map = try elf.readELF(input);
 
     // Align segments to 64 byte boundaries
-    elf.alignSegments(&map);
+    const dolMap = dol.createDOLMapping(map);
 
     // Write header and copy over segments from input
     const output = try std.fs.cwd().createFile(outputPath, .{});
     defer output.close();
-    try elf.writeDOL(map, input, output);
+    try dol.writeDOL(dolMap, input, output);
 }