authorgravatar for kubkon@jakubkonka.comJakub Konka <kubkon@jakubkonka.com> 2023-11-03 10:03:03+01:00
committergravatar for kubkon@jakubkonka.comJakub Konka <kubkon@jakubkonka.com> 2023-11-04 09:12:26+01:00
log33a0a72e87bd01ce6dbd10fa327c74168a0166db
treeef016abc30e70792ab37cb872e2bf4d1dba79a9a
parent875beb25b5493ee3b0aedd730f831e4ea5d124cc

elf: align ar_hdr to at least 2 bytes


2 files changed, 18 insertions(+), 5 deletions(-)

src/link/Elf.zig+17-4
......@@ -1580,6 +1580,13 @@ pub fn flushStaticLib(self: *Elf, comp: *Compilation) link.File.FlushError!void
15801580 files.putAssumeCapacityNoClobber(zig_object.index, .{ off, 0, 0 });
15811581 }
15821582
1583 // Align to even byte boundary
1584 {
1585 const end = ar_strtab.items.len;
1586 const aligned = mem.alignForward(usize, end, 2);
1587 try ar_strtab.writer().writeByteNTimes(0, aligned - end);
1588 }
1589
15831590 // Encode ar symtab in 64bit format.
15841591 var ar_symtab = std.ArrayList(u8).init(gpa);
15851592 defer ar_symtab.deinit();
......@@ -1599,7 +1606,7 @@ pub fn flushStaticLib(self: *Elf, comp: *Compilation) link.File.FlushError!void
15991606 try ar_symtab.writer().print("{s}\x00", .{name});
16001607 }
16011608
1602 // Align to 8bytes if required
1609 // Align to 8 bytes if required
16031610 {
16041611 const end = ar_symtab.items.len;
16051612 const aligned = mem.alignForward(usize, end, 8);
......@@ -1617,8 +1624,6 @@ pub fn flushStaticLib(self: *Elf, comp: *Compilation) link.File.FlushError!void
16171624 file_off += @sizeOf(Archive.ar_hdr) + @as(u64, @intCast(ar_symtab.items.len));
16181625 // Strtab
16191626 file_off += @sizeOf(Archive.ar_hdr) + @as(u64, @intCast(ar_strtab.items.len));
1620 // And because we are nice, we will align to 8 bytes.
1621 file_off = mem.alignForward(u64, file_off, 8);
16221627
16231628 const files_ptr = files.getPtr(zig_object.index).?;
16241629 files_ptr[1] = file_off;
......@@ -1661,7 +1666,7 @@ pub fn flushStaticLib(self: *Elf, comp: *Compilation) link.File.FlushError!void
16611666 const hdr = setArHdr(.{
16621667 .kind = .strtab,
16631668 .name_off = 0,
1664 .size = @intCast(mem.alignForward(usize, ar_strtab.items.len, 8)),
1669 .size = @intCast(ar_strtab.items.len),
16651670 });
16661671 try self.base.file.?.pwriteAll(mem.asBytes(&hdr), pos);
16671672 pos += @sizeOf(Archive.ar_hdr);
......@@ -1674,8 +1679,16 @@ pub fn flushStaticLib(self: *Elf, comp: *Compilation) link.File.FlushError!void
16741679 const entry = files.get(zig_object.index).?;
16751680 const hdr = setArHdr(.{ .kind = .object, .name_off = entry[0], .size = @intCast(entry[2]) });
16761681 try self.base.file.?.pwriteAll(mem.asBytes(&hdr), entry[1]);
1682 pos += @sizeOf(Archive.ar_hdr) + entry[2];
16771683 }
16781684
1685 if (pos % 2 != 0) {
1686 pos += 1;
1687 try self.base.file.?.pwriteAll(&[1]u8{0}, pos);
1688 }
1689
1690 assert(mem.isAligned(pos, 2));
1691
16791692 // TODO parsed positionals
16801693
16811694 // Magic bytes.
src/link/Elf/Archive.zig+1-1
......@@ -88,7 +88,7 @@ pub fn parse(self: *Archive, elf_file: *Elf) !void {
8888 if (stream.pos % 2 != 0) {
8989 stream.pos += 1;
9090 }
91
91 // TODO flag an error if stream.pos > self.data.len after alignment
9292 const hdr = reader.readStruct(ar_hdr) catch break;
9393
9494 if (!mem.eql(u8, &hdr.ar_fmag, ARFMAG)) {