authorgravatar for kubkon@jakubkonka.comJakub Konka <kubkon@jakubkonka.com> 2023-11-05 13:37:13+01:00
committergravatar for kubkon@jakubkonka.comJakub Konka <kubkon@jakubkonka.com> 2023-11-05 13:37:13+01:00
log8142925c7e5cb6ec21ca7046b37140a735735b51
treea63d8afa243a16248b85266e80f19ab0d09a3872
parent55fa8a04f1853deb473339cdc610cbf012ae0d61

elf: hook up saving object files in an archive

5 files changed, 61 insertions(+), 27 deletions(-)

src/link/Elf.zig+6-1
......@@ -288,7 +288,9 @@ pub fn openPath(allocator: Allocator, sub_path: []const u8, options: link.Option
288288 const index = @as(File.Index, @intCast(try self.files.addOne(allocator)));
289289 self.files.set(index, .{ .zig_object = .{
290290 .index = index,
291 .path = options.module.?.main_mod.root_src_path,
291 .path = try std.fmt.allocPrint(self.base.allocator, "{s}.o", .{std.fs.path.stem(
292 options.module.?.main_mod.root_src_path,
293 )}),
292294 } });
293295 self.zig_object_index = index;
294296 try self.zigObjectPtr().?.init(self);
......@@ -1553,6 +1555,9 @@ pub fn flushStaticLib(self: *Elf, comp: *Compilation) link.File.FlushError!void
15531555 var files = std.ArrayList(File.Index).init(gpa);
15541556 defer files.deinit();
15551557 try files.ensureTotalCapacityPrecise(self.objects.items.len + 1);
1558 // Note to self: we currently must have ZigObject written out first as we write the object
1559 // file into the same file descriptor and then re-read its contents.
1560 // TODO implement writing ZigObject to a buffer instead of file.
15561561 if (self.zigObjectPtr()) |zig_object| files.appendAssumeCapacity(zig_object.index);
15571562 for (self.objects.items) |index| files.appendAssumeCapacity(index);
15581563
src/link/Elf/Archive.zig+4
......@@ -142,6 +142,7 @@ const SYMDEFNAME = genSpecialMemberName("__.SYMDEF");
142142const SYMDEFSORTEDNAME = genSpecialMemberName("__.SYMDEF SORTED");
143143
144144const strtab_delimiter = '\n';
145pub const max_member_name_len = 15;
145146
146147pub const ar_hdr = extern struct {
147148 /// Member file name, sometimes / terminated.
......@@ -248,6 +249,9 @@ pub const ArSymtab = struct {
248249 if (elf_file.zigObjectPtr()) |zig_object| {
249250 offsets.putAssumeCapacityNoClobber(zig_object.index, zig_object.output_ar_state.file_off);
250251 }
252 for (elf_file.objects.items) |index| {
253 offsets.putAssumeCapacityNoClobber(index, elf_file.file(index).?.object.output_ar_state.file_off);
254 }
251255
252256 // Number of symbols
253257 try writer.writeInt(u64, @as(u64, @intCast(ar.symtab.items.len)), .big);
src/link/Elf/Object.zig+30
......@@ -654,6 +654,36 @@ pub fn allocateAtoms(self: Object, elf_file: *Elf) void {
654654 }
655655}
656656
657pub fn updateArSymtab(self: Object, ar_symtab: *Archive.ArSymtab, elf_file: *Elf) !void {
658 const gpa = elf_file.base.allocator;
659 const start = self.first_global orelse self.symtab.items.len;
660
661 try ar_symtab.symtab.ensureUnusedCapacity(gpa, self.symtab.items.len - start);
662
663 for (self.symtab.items[start..]) |sym| {
664 if (sym.st_shndx == elf.SHN_UNDEF) continue;
665 const off = try ar_symtab.strtab.insert(gpa, self.getString(sym.st_name));
666 ar_symtab.symtab.appendAssumeCapacity(.{ .off = off, .file_index = self.index });
667 }
668}
669
670pub fn updateArSize(self: *Object) void {
671 self.output_ar_state.size = self.data.len;
672}
673
674pub fn writeAr(self: Object, writer: anytype) !void {
675 const name = self.path;
676 const hdr = Archive.setArHdr(.{
677 .name = if (name.len <= Archive.max_member_name_len)
678 .{ .name = name }
679 else
680 .{ .name_off = self.output_ar_state.name_off },
681 .size = @intCast(self.data.len),
682 });
683 try writer.writeAll(mem.asBytes(&hdr));
684 try writer.writeAll(self.data);
685}
686
657687pub fn locals(self: Object) []const Symbol.Index {
658688 const end = self.first_global orelse self.symbols.items.len;
659689 return self.symbols.items[0..end];
src/link/Elf/ZigObject.zig+8-19
......@@ -3,7 +3,6 @@
33//! and any relocations that may have been emitted.
44//! Think about this as fake in-memory Object file for the Zig module.
55
6/// Path is owned by Module and lives as long as *Module.
76path: []const u8,
87index: File.Index,
98
......@@ -78,7 +77,7 @@ pub fn init(self: *ZigObject, elf_file: *Elf) !void {
7877 try self.atoms.append(gpa, 0); // null input section
7978 try self.strtab.buffer.append(gpa, 0);
8079
81 const name_off = try self.strtab.insert(gpa, std.fs.path.stem(self.path));
80 const name_off = try self.strtab.insert(gpa, self.path);
8281 const symbol_index = try elf_file.addSymbol();
8382 try self.local_symbols.append(gpa, symbol_index);
8483 const symbol_ptr = elf_file.symbol(symbol_index);
......@@ -98,6 +97,7 @@ pub fn init(self: *ZigObject, elf_file: *Elf) !void {
9897}
9998
10099pub fn deinit(self: *ZigObject, allocator: Allocator) void {
100 allocator.free(self.path);
101101 self.local_esyms.deinit(allocator);
102102 self.global_esyms.deinit(allocator);
103103 self.strtab.deinit(allocator);
......@@ -512,25 +512,13 @@ pub fn updateArSymtab(self: ZigObject, ar_symtab: *Archive.ArSymtab, elf_file: *
512512 const global = elf_file.symbol(global_index);
513513 const file_ptr = global.file(elf_file).?;
514514 assert(file_ptr.index() == self.index);
515 if (global.type(elf_file) == elf.SHN_UNDEF) continue;
515 if (global.outputShndx() == null) continue;
516516
517517 const off = try ar_symtab.strtab.insert(gpa, global.name(elf_file));
518518 ar_symtab.symtab.appendAssumeCapacity(.{ .off = off, .file_index = self.index });
519519 }
520520}
521521
522pub fn updateArStrtab(
523 self: *ZigObject,
524 allocator: Allocator,
525 ar_strtab: *Archive.ArStrtab,
526) error{OutOfMemory}!void {
527 const name = try std.fmt.allocPrint(allocator, "{s}.o", .{std.fs.path.stem(self.path)});
528 defer allocator.free(name);
529 if (name.len <= 15) return;
530 const name_off = try ar_strtab.insert(allocator, name);
531 self.output_ar_state.name_off = name_off;
532}
533
534522pub fn updateArSize(self: *ZigObject, elf_file: *Elf) void {
535523 var end_pos: u64 = elf_file.shdr_table_offset.?;
536524 for (elf_file.shdrs.items) |shdr| {
......@@ -549,11 +537,12 @@ pub fn writeAr(self: ZigObject, elf_file: *Elf, writer: anytype) !void {
549537 const amt = try elf_file.base.file.?.preadAll(contents, 0);
550538 if (amt != self.output_ar_state.size) return error.InputOutput;
551539
552 const name = try std.fmt.allocPrint(gpa, "{s}.o", .{std.fs.path.stem(self.path)});
553 defer gpa.free(name);
554
540 const name = self.path;
555541 const hdr = Archive.setArHdr(.{
556 .name = if (name.len <= 15) .{ .name = name } else .{ .name_off = self.output_ar_state.name_off },
542 .name = if (name.len <= Archive.max_member_name_len)
543 .{ .name = name }
544 else
545 .{ .name_off = self.output_ar_state.name_off },
557546 .size = @intCast(size),
558547 });
559548 try writer.writeAll(mem.asBytes(&hdr));
src/link/Elf/file.zig+13-7
......@@ -199,23 +199,30 @@ pub const File = union(enum) {
199199 pub fn updateArSymtab(file: File, ar_symtab: *Archive.ArSymtab, elf_file: *Elf) !void {
200200 return switch (file) {
201201 .zig_object => |x| x.updateArSymtab(ar_symtab, elf_file),
202 .object => @panic("TODO"),
202 .object => |x| x.updateArSymtab(ar_symtab, elf_file),
203203 inline else => unreachable,
204204 };
205205 }
206206
207207 pub fn updateArStrtab(file: File, allocator: Allocator, ar_strtab: *Archive.ArStrtab) !void {
208 return switch (file) {
209 .zig_object => |x| x.updateArStrtab(allocator, ar_strtab),
210 .object => @panic("TODO"),
208 const path = switch (file) {
209 .zig_object => |x| x.path,
210 .object => |x| x.path,
211 inline else => unreachable,
212 };
213 const state = switch (file) {
214 .zig_object => |x| &x.output_ar_state,
215 .object => |x| &x.output_ar_state,
211216 inline else => unreachable,
212217 };
218 if (path.len <= Archive.max_member_name_len) return;
219 state.name_off = try ar_strtab.insert(allocator, path);
213220 }
214221
215222 pub fn updateArSize(file: File, elf_file: *Elf) void {
216223 return switch (file) {
217224 .zig_object => |x| x.updateArSize(elf_file),
218 .object => @panic("TODO"),
225 .object => |x| x.updateArSize(),
219226 inline else => unreachable,
220227 };
221228 }
......@@ -223,8 +230,7 @@ pub const File = union(enum) {
223230 pub fn writeAr(file: File, elf_file: *Elf, writer: anytype) !void {
224231 return switch (file) {
225232 .zig_object => |x| x.writeAr(elf_file, writer),
226 // .object => |x| x.writeAr(elf_file, writer),
227 .object => @panic("TODO"),
233 .object => |x| x.writeAr(writer),
228234 inline else => unreachable,
229235 };
230236 }