Commit f9eb14ddcf

Jakub Konka <kubkon@jakubkonka.com>
2024-02-07 19:08:15
macho: parse input object files specifically for incl in archive
1 parent 82144a9
Changed files (3)
src/link/MachO/Object.zig
@@ -1233,6 +1233,82 @@ fn addSection(self: *Object, allocator: Allocator, segname: []const u8, sectname
     return n_sect;
 }
 
+pub fn parseAr(self: *Object, macho_file: *MachO) !void {
+    const tracy = trace(@src());
+    defer tracy.end();
+
+    const gpa = macho_file.base.comp.gpa;
+    const offset = if (self.archive) |ar| ar.offset else 0;
+    const handle = macho_file.getFileHandle(self.file_handle);
+
+    var header_buffer: [@sizeOf(macho.mach_header_64)]u8 = undefined;
+    {
+        const amt = try handle.preadAll(&header_buffer, offset);
+        if (amt != @sizeOf(macho.mach_header_64)) return error.InputOutput;
+    }
+    self.header = @as(*align(1) const macho.mach_header_64, @ptrCast(&header_buffer)).*;
+
+    const this_cpu_arch: std.Target.Cpu.Arch = switch (self.header.?.cputype) {
+        macho.CPU_TYPE_ARM64 => .aarch64,
+        macho.CPU_TYPE_X86_64 => .x86_64,
+        else => |x| {
+            try macho_file.reportParseError2(self.index, "unknown cpu architecture: {d}", .{x});
+            return error.InvalidCpuArch;
+        },
+    };
+    if (macho_file.getTarget().cpu.arch != this_cpu_arch) {
+        try macho_file.reportParseError2(self.index, "invalid cpu architecture: {s}", .{@tagName(this_cpu_arch)});
+        return error.InvalidCpuArch;
+    }
+
+    const lc_buffer = try gpa.alloc(u8, self.header.?.sizeofcmds);
+    defer gpa.free(lc_buffer);
+    {
+        const amt = try handle.preadAll(lc_buffer, offset + @sizeOf(macho.mach_header_64));
+        if (amt != self.header.?.sizeofcmds) return error.InputOutput;
+    }
+
+    var it = LoadCommandIterator{
+        .ncmds = self.header.?.ncmds,
+        .buffer = lc_buffer,
+    };
+    while (it.next()) |lc| switch (lc.cmd()) {
+        .SYMTAB => {
+            const cmd = lc.cast(macho.symtab_command).?;
+            try self.strtab.resize(gpa, cmd.strsize);
+            {
+                const amt = try handle.preadAll(self.strtab.items, cmd.stroff + offset);
+                if (amt != self.strtab.items.len) return error.InputOutput;
+            }
+
+            const symtab_buffer = try gpa.alloc(u8, cmd.nsyms * @sizeOf(macho.nlist_64));
+            defer gpa.free(symtab_buffer);
+            {
+                const amt = try handle.preadAll(symtab_buffer, cmd.symoff + offset);
+                if (amt != symtab_buffer.len) return error.InputOutput;
+            }
+            const symtab = @as([*]align(1) const macho.nlist_64, @ptrCast(symtab_buffer.ptr))[0..cmd.nsyms];
+            try self.symtab.ensureUnusedCapacity(gpa, symtab.len);
+            for (symtab) |nlist| {
+                self.symtab.appendAssumeCapacity(.{
+                    .nlist = nlist,
+                    .atom = 0,
+                    .size = 0,
+                });
+            }
+        },
+        .BUILD_VERSION,
+        .VERSION_MIN_MACOSX,
+        .VERSION_MIN_IPHONEOS,
+        .VERSION_MIN_TVOS,
+        .VERSION_MIN_WATCHOS,
+        => if (self.platform == null) {
+            self.platform = MachO.Platform.fromLoadCommand(lc);
+        },
+        else => {},
+    };
+}
+
 pub fn updateArSymtab(self: Object, ar_symtab: *Archive.ArSymtab, macho_file: *MachO) error{OutOfMemory}!void {
     const gpa = macho_file.base.comp.gpa;
     for (self.symtab.items(.nlist)) |nlist| {
src/link/MachO/relocatable.zig
@@ -104,8 +104,19 @@ pub fn flushStaticLib(macho_file: *MachO, comp: *Compilation, module_obj_path: ?
     if (module_obj_path) |path| try positionals.append(.{ .path = path });
 
     for (positionals.items) |obj| {
-        // TODO: parse for archive meaning don't unpack objects
-        _ = obj;
+        parsePositional(macho_file, obj.path) catch |err| switch (err) {
+            error.MalformedObject,
+            error.MalformedArchive,
+            error.InvalidCpuArch,
+            error.InvalidTarget,
+            => continue, // already reported
+            error.UnknownFileType => try macho_file.reportParseError(obj.path, "unknown file type for an object file", .{}),
+            else => |e| try macho_file.reportParseError(
+                obj.path,
+                "unexpected error: parsing input file failed with error {s}",
+                .{@errorName(e)},
+            ),
+        };
     }
 
     if (comp.link_errors.items.len > 0) return error.FlushFailure;
@@ -241,6 +252,75 @@ pub fn flushStaticLib(macho_file: *MachO, comp: *Compilation, module_obj_path: ?
     if (comp.link_errors.items.len > 0) return error.FlushFailure;
 }
 
+fn parsePositional(macho_file: *MachO, path: []const u8) MachO.ParseError!void {
+    const tracy = trace(@src());
+    defer tracy.end();
+    if (try Object.isObject(path)) {
+        try parseObject(macho_file, path);
+    } else if (try fat.isFatLibrary(path)) {
+        const fat_arch = try macho_file.parseFatLibrary(path);
+        if (try Archive.isArchive(path, fat_arch)) {
+            try parseArchive(macho_file, path, fat_arch);
+        } else return error.UnknownFileType;
+    } else if (try Archive.isArchive(path, null)) {
+        try parseArchive(macho_file, path, null);
+    } else return error.UnknownFileType;
+}
+
+fn parseObject(macho_file: *MachO, path: []const u8) MachO.ParseError!void {
+    const tracy = trace(@src());
+    defer tracy.end();
+
+    const gpa = macho_file.base.comp.gpa;
+    const file = try std.fs.cwd().openFile(path, .{});
+    errdefer file.close();
+    const handle = try macho_file.addFileHandle(file);
+    const mtime: u64 = mtime: {
+        const stat = file.stat() catch break :mtime 0;
+        break :mtime @as(u64, @intCast(@divFloor(stat.mtime, 1_000_000_000)));
+    };
+    const index = @as(File.Index, @intCast(try macho_file.files.addOne(gpa)));
+    macho_file.files.set(index, .{ .object = .{
+        .path = try gpa.dupe(u8, path),
+        .file_handle = handle,
+        .mtime = mtime,
+        .index = index,
+    } });
+    try macho_file.objects.append(gpa, index);
+
+    const object = macho_file.getFile(index).?.object;
+    try object.parseAr(macho_file);
+}
+
+fn parseArchive(macho_file: *MachO, path: []const u8, fat_arch: ?fat.Arch) MachO.ParseError!void {
+    const tracy = trace(@src());
+    defer tracy.end();
+
+    const gpa = macho_file.base.comp.gpa;
+
+    const file = try std.fs.cwd().openFile(path, .{});
+    errdefer file.close();
+    const handle = try macho_file.addFileHandle(file);
+
+    var archive = Archive{};
+    defer archive.deinit(gpa);
+    try archive.parse(macho_file, path, handle, fat_arch);
+
+    var has_parse_error = false;
+    for (archive.objects.items) |extracted| {
+        const index = @as(File.Index, @intCast(try macho_file.files.addOne(gpa)));
+        macho_file.files.set(index, .{ .object = extracted });
+        const object = &macho_file.files.items(.data)[index].object;
+        object.index = index;
+        object.parseAr(macho_file) catch |err| switch (err) {
+            error.InvalidCpuArch => has_parse_error = true,
+            else => |e| return e,
+        };
+        try macho_file.objects.append(gpa, index);
+    }
+    if (has_parse_error) return error.MalformedArchive;
+}
+
 fn markExports(macho_file: *MachO) void {
     if (macho_file.getZigObject()) |zo| {
         zo.asFile().markExportsRelocatable(macho_file);
@@ -733,6 +813,7 @@ fn writeHeader(macho_file: *MachO, ncmds: usize, sizeofcmds: usize) !void {
 const assert = std.debug.assert;
 const build_options = @import("build_options");
 const eh_frame = @import("eh_frame.zig");
+const fat = @import("fat.zig");
 const link = @import("../../link.zig");
 const load_commands = @import("load_commands.zig");
 const log = std.log.scoped(.link);
@@ -748,4 +829,5 @@ const Atom = @import("Atom.zig");
 const Compilation = @import("../../Compilation.zig");
 const File = @import("file.zig").File;
 const MachO = @import("../MachO.zig");
+const Object = @import("Object.zig");
 const Symbol = @import("Symbol.zig");
src/link/MachO.zig
@@ -926,7 +926,7 @@ pub fn resolveLibSystem(
     });
 }
 
-const ParseError = error{
+pub const ParseError = error{
     MalformedObject,
     MalformedArchive,
     MalformedDylib,
@@ -1003,7 +1003,7 @@ fn parseObject(self: *MachO, path: []const u8) ParseError!void {
     try object.parse(self);
 }
 
-fn parseFatLibrary(self: *MachO, path: []const u8) !fat.Arch {
+pub fn parseFatLibrary(self: *MachO, path: []const u8) !fat.Arch {
     var buffer: [2]fat.Arch = undefined;
     const fat_archs = try fat.parseArchs(path, &buffer);
     const cpu_arch = self.getTarget().cpu.arch;