1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
|
value: i64 = 0,
size: u64 = 0,
alignment: Atom.Alignment = .@"1",
output_section_index: u32 = 0,
// atoms: std.ArrayListUnmanaged(Elf.Ref) = .empty,
atoms: std.AutoArrayHashMapUnmanaged(Elf.Ref, void) = .empty,
dirty: bool = true,
pub fn deinit(list: *AtomList, allocator: Allocator) void {
list.atoms.deinit(allocator);
}
pub fn address(list: AtomList, elf_file: *Elf) i64 {
const shdr = elf_file.sections.items(.shdr)[list.output_section_index];
return @as(i64, @intCast(shdr.sh_addr)) + list.value;
}
pub fn offset(list: AtomList, elf_file: *Elf) u64 {
const shdr = elf_file.sections.items(.shdr)[list.output_section_index];
return shdr.sh_offset + @as(u64, @intCast(list.value));
}
pub fn updateSize(list: *AtomList, elf_file: *Elf) void {
assert(list.dirty);
for (list.atoms.keys()) |ref| {
const atom_ptr = elf_file.atom(ref).?;
assert(atom_ptr.alive);
const off = atom_ptr.alignment.forward(list.size);
const padding = off - list.size;
atom_ptr.value = @intCast(off);
list.size += padding + atom_ptr.size;
list.alignment = list.alignment.max(atom_ptr.alignment);
}
}
pub fn allocate(list: *AtomList, elf_file: *Elf) !void {
assert(list.dirty);
const alloc_res = try elf_file.allocateChunk(.{
.shndx = list.output_section_index,
.size = list.size,
.alignment = list.alignment,
.requires_padding = false,
});
list.value = @intCast(alloc_res.value);
log.debug("allocated atom_list({d}) at 0x{x}", .{ list.output_section_index, list.address(elf_file) });
const slice = elf_file.sections.slice();
const shdr = &slice.items(.shdr)[list.output_section_index];
const last_atom_ref = &slice.items(.last_atom)[list.output_section_index];
const expand_section = if (elf_file.atom(alloc_res.placement)) |placement_atom|
placement_atom.nextAtom(elf_file) == null
else
true;
if (expand_section) last_atom_ref.* = list.lastAtom(elf_file).ref();
shdr.sh_addralign = @max(shdr.sh_addralign, list.alignment.toByteUnits().?);
// This currently ignores Thunks as valid chunks.
{
var idx: usize = 0;
while (idx < list.atoms.keys().len) : (idx += 1) {
const curr_atom_ptr = elf_file.atom(list.atoms.keys()[idx]).?;
if (idx > 0) {
curr_atom_ptr.prev_atom_ref = list.atoms.keys()[idx - 1];
}
if (idx + 1 < list.atoms.keys().len) {
curr_atom_ptr.next_atom_ref = list.atoms.keys()[idx + 1];
}
}
}
if (elf_file.atom(alloc_res.placement)) |placement_atom| {
list.firstAtom(elf_file).prev_atom_ref = placement_atom.ref();
list.lastAtom(elf_file).next_atom_ref = placement_atom.next_atom_ref;
placement_atom.next_atom_ref = list.firstAtom(elf_file).ref();
}
// If we had a link from Atom to parent AtomList we would not need to
// update Atom's value or osec index.
for (list.atoms.keys()) |ref| {
const atom_ptr = elf_file.atom(ref).?;
atom_ptr.output_section_index = list.output_section_index;
atom_ptr.value += list.value;
}
list.dirty = false;
}
pub fn write(list: AtomList, buffer: *std.Io.Writer.Allocating, undefs: anytype, elf_file: *Elf) !void {
const gpa = elf_file.base.comp.gpa;
const osec = elf_file.sections.items(.shdr)[list.output_section_index];
assert(osec.sh_type != elf.SHT_NOBITS);
assert(!list.dirty);
log.debug("writing atoms in section '{s}'", .{elf_file.getShString(osec.sh_name)});
const list_size = math.cast(usize, list.size) orelse return error.Overflow;
try buffer.writer.splatByteAll(0, list_size);
for (list.atoms.keys()) |ref| {
const atom_ptr = elf_file.atom(ref).?;
assert(atom_ptr.alive);
const off = math.cast(usize, atom_ptr.value - list.value) orelse return error.Overflow;
const size = math.cast(usize, atom_ptr.size) orelse return error.Overflow;
log.debug(" atom({f}) at 0x{x}", .{ ref, list.offset(elf_file) + off });
const object = atom_ptr.file(elf_file).?.object;
const code = try object.codeDecompressAlloc(elf_file, ref.index);
defer gpa.free(code);
const out_code = buffer.written()[off..][0..size];
@memcpy(out_code, code);
if (osec.sh_flags & elf.SHF_ALLOC == 0)
try atom_ptr.resolveRelocsNonAlloc(elf_file, out_code, undefs)
else
try atom_ptr.resolveRelocsAlloc(elf_file, out_code);
}
try elf_file.base.file.?.pwriteAll(buffer.written(), list.offset(elf_file));
buffer.clearRetainingCapacity();
}
pub fn writeRelocatable(list: AtomList, buffer: *std.array_list.Managed(u8), elf_file: *Elf) !void {
const gpa = elf_file.base.comp.gpa;
const osec = elf_file.sections.items(.shdr)[list.output_section_index];
assert(osec.sh_type != elf.SHT_NOBITS);
log.debug("writing atoms in section '{s}'", .{elf_file.getShString(osec.sh_name)});
const list_size = math.cast(usize, list.size) orelse return error.Overflow;
try buffer.ensureUnusedCapacity(list_size);
buffer.appendNTimesAssumeCapacity(0, list_size);
for (list.atoms.keys()) |ref| {
const atom_ptr = elf_file.atom(ref).?;
assert(atom_ptr.alive);
const off = math.cast(usize, atom_ptr.value - list.value) orelse return error.Overflow;
const size = math.cast(usize, atom_ptr.size) orelse return error.Overflow;
log.debug(" atom({f}) at 0x{x}", .{ ref, list.offset(elf_file) + off });
const object = atom_ptr.file(elf_file).?.object;
const code = try object.codeDecompressAlloc(elf_file, ref.index);
defer gpa.free(code);
const out_code = buffer.items[off..][0..size];
@memcpy(out_code, code);
}
try elf_file.base.file.?.pwriteAll(buffer.items, list.offset(elf_file));
buffer.clearRetainingCapacity();
}
pub fn firstAtom(list: AtomList, elf_file: *Elf) *Atom {
assert(list.atoms.keys().len > 0);
return elf_file.atom(list.atoms.keys()[0]).?;
}
pub fn lastAtom(list: AtomList, elf_file: *Elf) *Atom {
assert(list.atoms.keys().len > 0);
return elf_file.atom(list.atoms.keys()[list.atoms.keys().len - 1]).?;
}
const Format = struct {
atom_list: AtomList,
elf_file: *Elf,
fn default(f: Format, writer: *std.Io.Writer) std.Io.Writer.Error!void {
const list = f.atom_list;
try writer.print("list : @{x} : shdr({d}) : align({x}) : size({x})", .{
list.address(f.elf_file),
list.output_section_index,
list.alignment.toByteUnits() orelse 0,
list.size,
});
try writer.writeAll(" : atoms{ ");
for (list.atoms.keys(), 0..) |ref, i| {
try writer.print("{f}", .{ref});
if (i < list.atoms.keys().len - 1) try writer.writeAll(", ");
}
try writer.writeAll(" }");
}
};
pub fn fmt(atom_list: AtomList, elf_file: *Elf) std.fmt.Alt(Format, Format.default) {
return .{ .data = .{ .atom_list = atom_list, .elf_file = elf_file } };
}
const assert = std.debug.assert;
const elf = std.elf;
const log = std.log.scoped(.link);
const math = std.math;
const std = @import("std");
const Allocator = std.mem.Allocator;
const Atom = @import("Atom.zig");
const AtomList = @This();
const Elf = @import("../Elf.zig");
const Object = @import("Object.zig");
|
