1//===- XCOFFWriter.cpp ----------------------------------------------------===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8
9#include "llvm/Support/Errc.h"
10#include "XCOFFWriter.h"
11
12namespace llvm {
13namespace objcopy {
14namespace xcoff {
15
16using namespace object;
17
18void XCOFFWriter::finalizeHeaders() {
19 // File header.
20 FileSize += sizeof(XCOFFFileHeader32);
21 // Optional file header.
22 FileSize += Obj.FileHeader.AuxHeaderSize;
23 // Section headers.
24 FileSize += sizeof(XCOFFSectionHeader32) * Obj.Sections.size();
25}
26
27void XCOFFWriter::finalizeSections() {
28 for (const Section &Sec : Obj.Sections) {
29 // Section data.
30 FileSize += Sec.Contents.size();
31 // Relocations.
32 FileSize +=
33 Sec.SectionHeader.NumberOfRelocations * sizeof(XCOFFRelocation32);
34 }
35}
36
37void XCOFFWriter::finalizeSymbolStringTable() {
38 assert(Obj.FileHeader.SymbolTableOffset >= FileSize);
39 FileSize = Obj.FileHeader.SymbolTableOffset;
40 // Symbols and auxiliary entries.
41 FileSize +=
42 Obj.FileHeader.NumberOfSymTableEntries * XCOFF::SymbolTableEntrySize;
43 // String table.
44 FileSize += Obj.StringTable.size();
45}
46
47void XCOFFWriter::finalize() {
48 FileSize = 0;
49 finalizeHeaders();
50 finalizeSections();
51 finalizeSymbolStringTable();
52}
53
54void XCOFFWriter::writeHeaders() {
55 // Write the file header.
56 uint8_t *Ptr = reinterpret_cast<uint8_t *>(Buf->getBufferStart());
57 memcpy(dest: Ptr, src: &Obj.FileHeader, n: sizeof(XCOFFFileHeader32));
58 Ptr += sizeof(XCOFFFileHeader32);
59
60 // Write the optional header.
61 if (Obj.FileHeader.AuxHeaderSize) {
62 memcpy(dest: Ptr, src: &Obj.OptionalFileHeader, n: Obj.FileHeader.AuxHeaderSize);
63 Ptr += Obj.FileHeader.AuxHeaderSize;
64 }
65
66 // Write section headers.
67 for (const Section &Sec : Obj.Sections) {
68 memcpy(dest: Ptr, src: &Sec.SectionHeader, n: sizeof(XCOFFSectionHeader32));
69 Ptr += sizeof(XCOFFSectionHeader32);
70 }
71}
72
73void XCOFFWriter::writeSections() {
74 // Write section data.
75 for (const Section &Sec : Obj.Sections) {
76 uint8_t *Ptr = reinterpret_cast<uint8_t *>(Buf->getBufferStart()) +
77 Sec.SectionHeader.FileOffsetToRawData;
78 Ptr = llvm::copy(Range: Sec.Contents, Out: Ptr);
79 }
80
81 // Write relocations.
82 for (const Section &Sec : Obj.Sections) {
83 uint8_t *Ptr = reinterpret_cast<uint8_t *>(Buf->getBufferStart()) +
84 Sec.SectionHeader.FileOffsetToRelocationInfo;
85 for (const XCOFFRelocation32 &Rel : Sec.Relocations) {
86 memcpy(dest: Ptr, src: &Rel, n: sizeof(XCOFFRelocation32));
87 Ptr += sizeof(XCOFFRelocation32);
88 }
89 }
90}
91
92void XCOFFWriter::writeSymbolStringTable() {
93 // Write symbols.
94 uint8_t *Ptr = reinterpret_cast<uint8_t *>(Buf->getBufferStart()) +
95 Obj.FileHeader.SymbolTableOffset;
96 for (const Symbol &Sym : Obj.Symbols) {
97 memcpy(dest: Ptr, src: &Sym.Sym, n: XCOFF::SymbolTableEntrySize);
98 Ptr += XCOFF::SymbolTableEntrySize;
99 // Auxiliary symbols.
100 memcpy(dest: Ptr, src: Sym.AuxSymbolEntries.data(), n: Sym.AuxSymbolEntries.size());
101 Ptr += Sym.AuxSymbolEntries.size();
102 }
103 // Write the string table.
104 memcpy(dest: Ptr, src: Obj.StringTable.data(), n: Obj.StringTable.size());
105 Ptr += Obj.StringTable.size();
106}
107
108Error XCOFFWriter::write() {
109 finalize();
110 Buf = WritableMemoryBuffer::getNewMemBuffer(Size: FileSize);
111 if (!Buf)
112 return createStringError(EC: errc::not_enough_memory,
113 S: "failed to allocate memory buffer of " +
114 Twine::utohexstr(Val: FileSize) + " bytes");
115
116 writeHeaders();
117 writeSections();
118 writeSymbolStringTable();
119 Out.write(Ptr: Buf->getBufferStart(), Size: Buf->getBufferSize());
120 return Error::success();
121}
122
123} // end namespace xcoff
124} // end namespace objcopy
125} // end namespace llvm
126