Adding changes to support GNU style archive library reading

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167853 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Shankar Easwaran
2012-11-13 18:38:42 +00:00
parent f741482387
commit 206252cc9f
9 changed files with 431 additions and 26 deletions

View File

@ -122,7 +122,14 @@ error_code Archive::Child::getName(StringRef &Result) const {
+ sizeof(ArchiveMemberHeader)
+ Parent->StringTable->getSize()))
return object_error::parse_failed;
Result = addr;
// GNU long file names end with a /.
if (Parent->kind() == K_GNU) {
StringRef::size_type End = StringRef(addr).find('/');
Result = StringRef(addr, End);
} else {
Result = addr;
}
return object_error::success;
} else if (name.startswith("#1/")) {
APInt name_size;
@ -187,15 +194,52 @@ Archive::Archive(MemoryBuffer *source, error_code &ec)
child_iterator i = begin_children(false);
child_iterator e = end_children();
if (i != e) ++i; // Nobody cares about the first member.
if (i != e) {
SymbolTable = i;
++i;
}
if (i != e) {
StringTable = i;
}
StringRef name;
if ((ec = i->getName(name)))
return;
// Below is the pattern that is used to figure out the archive format
// GNU archive format
// First member : / (points to the symbol table )
// Second member : // (may exist, if it exists, points to the string table)
// Note : The string table is used if the filename exceeds 15 characters
// BSD archive format
// First member : __.SYMDEF (points to the symbol table)
// There is no string table, if the filename exceeds 15 characters or has a
// embedded space, the filename has #1/<size>, The size represents the size
// of the filename that needs to be read after the archive header
// COFF archive format
// First member : /
// Second member : / (provides a directory of symbols)
// Third member : // contains the string table, this is present even if the
// string table is empty
if (name == "/") {
SymbolTable = i;
StringTable = e;
if (i != e) ++i;
if ((ec = i->getName(name)))
return;
if (name[0] != '/') {
Format = K_GNU;
} else if ((name.size() > 1) && (name == "//")) {
Format = K_GNU;
StringTable = i;
++i;
} else {
Format = K_COFF;
if (i != e) {
SymbolTable = i;
++i;
}
if (i != e) {
StringTable = i;
}
}
} else if (name == "__.SYMDEF") {
Format = K_BSD;
SymbolTable = i;
StringTable = e;
}
ec = object_error::success;
}
@ -222,17 +266,28 @@ error_code Archive::Symbol::getName(StringRef &Result) const {
error_code Archive::Symbol::getMember(child_iterator &Result) const {
const char *buf = Parent->SymbolTable->getBuffer()->getBufferStart();
uint32_t member_count = *reinterpret_cast<const support::ulittle32_t*>(buf);
const char *offsets = buf + 4;
buf += 4 + (member_count * 4); // Skip offsets.
const char *indicies = buf + 4;
uint16_t offsetindex =
*(reinterpret_cast<const support::ulittle16_t*>(indicies)
+ SymbolIndex);
uint32_t offset = *(reinterpret_cast<const support::ulittle32_t*>(offsets)
+ (offsetindex - 1));
uint32_t offset = 0;
if (Parent->kind() == K_GNU) {
offset = *(reinterpret_cast<const support::ubig32_t*>(offsets)
+ SymbolIndex);
} else if (Parent->kind() == K_BSD) {
assert("BSD format is not supported");
} else {
uint32_t member_count = 0;
member_count = *reinterpret_cast<const support::ulittle32_t*>(buf);
buf += 4 + (member_count * 4); // Skip offsets.
const char *indicies = buf + 4;
uint16_t offsetindex =
*(reinterpret_cast<const support::ulittle16_t*>(indicies)
+ SymbolIndex);
uint32_t *offsetaddr =
(uint32_t *)(reinterpret_cast<const support::ulittle32_t*>(offsets)
+ (offsetindex - 1));
assert((const char *)offsetaddr <
Parent->SymbolTable->getBuffer()->getBufferEnd());
offset = *(offsetaddr);
}
const char *Loc = Parent->getData().begin() + offset;
size_t Size = sizeof(ArchiveMemberHeader) +
@ -253,10 +308,20 @@ Archive::Symbol Archive::Symbol::getNext() const {
Archive::symbol_iterator Archive::begin_symbols() const {
const char *buf = SymbolTable->getBuffer()->getBufferStart();
uint32_t member_count = *reinterpret_cast<const support::ulittle32_t*>(buf);
buf += 4 + (member_count * 4); // Skip offsets.
uint32_t symbol_count = *reinterpret_cast<const support::ulittle32_t*>(buf);
buf += 4 + (symbol_count * 2); // Skip indices.
if (kind() == K_GNU) {
uint32_t symbol_count = 0;
symbol_count = *reinterpret_cast<const support::ubig32_t*>(buf);
buf += sizeof(uint32_t) + (symbol_count * (sizeof(uint32_t)));
} else if (kind() == K_BSD) {
assert("BSD archive format is not supported");
} else {
uint32_t member_count = 0;
uint32_t symbol_count = 0;
member_count = *reinterpret_cast<const support::ulittle32_t*>(buf);
buf += 4 + (member_count * 4); // Skip offsets.
symbol_count = *reinterpret_cast<const support::ulittle32_t*>(buf);
buf += 4 + (symbol_count * 2); // Skip indices.
}
uint32_t string_start_offset =
buf - SymbolTable->getBuffer()->getBufferStart();
return symbol_iterator(Symbol(this, 0, string_start_offset));
@ -264,9 +329,36 @@ Archive::symbol_iterator Archive::begin_symbols() const {
Archive::symbol_iterator Archive::end_symbols() const {
const char *buf = SymbolTable->getBuffer()->getBufferStart();
uint32_t member_count = *reinterpret_cast<const support::ulittle32_t*>(buf);
buf += 4 + (member_count * 4); // Skip offsets.
uint32_t symbol_count = *reinterpret_cast<const support::ulittle32_t*>(buf);
uint32_t symbol_count = 0;
if (kind() == K_GNU) {
symbol_count = *reinterpret_cast<const support::ubig32_t*>(buf);
buf += sizeof(uint32_t) + (symbol_count * (sizeof(uint32_t)));
} else if (kind() == K_BSD) {
assert("BSD archive format is not supported");
} else {
uint32_t member_count = 0;
member_count = *reinterpret_cast<const support::ulittle32_t*>(buf);
buf += 4 + (member_count * 4); // Skip offsets.
symbol_count = *reinterpret_cast<const support::ulittle32_t*>(buf);
}
return symbol_iterator(
Symbol(this, symbol_count, 0));
}
Archive::child_iterator Archive::findSym(StringRef name) const {
Archive::symbol_iterator bs = begin_symbols();
Archive::symbol_iterator es = end_symbols();
Archive::child_iterator result;
StringRef symname;
for (; bs != es; ++bs) {
if (bs->getName(symname))
return end_children();
if (symname == name) {
if (bs->getMember(result))
return end_children();
return result;
}
}
return end_children();
}