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Completely rewritten to allow reading of archives and symbol table lookup in a more efficient manner.

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git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@17767 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Reid Spencer 2004-11-14 21:58:33 +00:00
parent bc9fc845a0
commit f9d7a51c44
2 changed files with 742 additions and 324 deletions
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513
lib/Archive/ArchiveReader.cpp
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@ -1,194 +1,403 @@
//===- lib/Archive/ArchiveReader.cpp - Read LLVM archive files ------------===//
//===-- ArchiveReader.cpp - Read LLVM archive files -------------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file was developed by the LLVM research group and is distributed under
// the University of Illinois Open Source License. See LICENSE.TXT for details.
// This file was developed by Reid Spencer and is distributed under the
// University of Illinois Open Source License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements the ReadArchiveFile interface, which allows a linker to
// read all of the LLVM bytecode files contained in a .a file. This file
// understands the standard system .a file format. This can only handle the .a
// variant prevalent on Linux systems so far, but may be extended. See
// information in this source file for more information:
// http://sources.redhat.com/cgi-bin/cvsweb.cgi/src/bfd/archive.c?cvsroot=src
// Builds up standard unix archive files (.a) containing LLVM bytecode.
//
//===----------------------------------------------------------------------===//
#include "ArchiveInternals.h"
#include "llvm/Bytecode/Reader.h"
#include "llvm/Module.h"
#include "llvm/Support/FileUtilities.h"
#include <cstdlib>
#include <iostream>
using namespace llvm;
namespace {
struct ar_hdr {
char name[16];
char date[12];
char uid[6];
char gid[6];
char mode[8];
char size[10];
char fmag[2]; // Always equal to '`\n'
};
enum ObjectType {
UserObject, // A user .o/.bc file
Unknown, // Unknown file, just ignore it
SVR4LongFilename, // a "//" section used for long file names
ArchiveSymbolTable, // Symbol table produced by ranlib.
};
/// Read a variable-bit-rate encoded unsigned integer
inline unsigned readInteger(const char*&At, const char*End) {
unsigned Shift = 0;
unsigned Result = 0;
do {
if (At == End)
throw std::string("Ran out of data reading vbr_uint!");
Result |= (unsigned)((*At++) & 0x7F) << Shift;
Shift += 7;
} while (At[-1] & 0x80);
return Result;
}
/// getObjectType - Determine the type of object that this header represents.
/// This is capable of parsing the variety of special sections used for various
/// purposes.
///
static enum ObjectType getObjectType(ar_hdr *H, std::string MemberName,
unsigned char *MemberData, unsigned Size) {
// Check for sections with special names...
if (MemberName == "__.SYMDEF " || MemberName == "__.SYMDEF SORTED")
return ArchiveSymbolTable;
else if (MemberName == "// ")
return SVR4LongFilename;
// Check to see if it looks like an llvm object file...
if (Size >= 4 && !memcmp(MemberData, "llvm", 4))
return UserObject;
if (Size >= 4 && !memcmp(MemberData, "llvc", 4))
return UserObject;
return Unknown;
}
static inline bool Error(std::string *ErrorStr, const char *Message) {
if (ErrorStr) *ErrorStr = Message;
// Completely parse the Archive's symbol table and populate symTab member var.
void
Archive::parseSymbolTable(const void* data, unsigned size) {
const char* At = (const char*) data;
const char* End = At + size;
while (At < End) {
unsigned offset = readInteger(At, End);
unsigned length = readInteger(At, End);
if (At + length > End)
throw std::string("malformed symbol table");
// we don't care if it can't be inserted (duplicate entry)
symTab.insert(std::make_pair(std::string(At,length),offset));
At += length;
}
symTabSize = size;
}
// This member parses an ArchiveMemberHeader that is presumed to be pointed to
// by At. The At pointer is updated to the byte just after the header, which
// can be variable in size.
ArchiveMember*
Archive::parseMemberHeader(const char*& At, const char* End) {
assert(At + sizeof(ArchiveMemberHeader) < End && "Not enough data");
// Cast archive member header
ArchiveMemberHeader* Hdr = (ArchiveMemberHeader*)At;
At += sizeof(ArchiveMemberHeader);
// Instantiate the ArchiveMember to be filled
ArchiveMember* member = new ArchiveMember(this);
// Extract the size and determine if the file is
// compressed or not (negative length).
int flags = 0;
int MemberSize = atoi(Hdr->size);
if (MemberSize < 0) {
flags |= ArchiveMember::CompressedFlag;
MemberSize = -MemberSize;
}
// Check the size of the member for sanity
if (At + MemberSize > End)
throw std::string("invalid member length in archive file");
// Check the member signature
if (!Hdr->checkSignature())
throw std::string("invalid file member signature");
// Convert and check the member name
// The empty name ( '/' and 15 blanks) is for a foreign (non-LLVM) symbol
// table. The special name "//" and 14 blanks is for a string table, used
// for long file names. This library doesn't generate either of those but
// it will accept them. If the name starts with #1/ and the remainder is
// digits, then those digits specify the length of the name that is
// stored immediately following the header. The special name
// __LLVM_SYM_TAB__ identifies the symbol table for LLVM bytecode.
// Anything else is a regular, short filename that is terminated with
// a '/' and blanks.
std::string pathname;
unsigned index;
switch (Hdr->name[0]) {
case '#':
if (Hdr->name[1] == '1' && Hdr->name[2] == '/') {
if (isdigit(Hdr->name[3])) {
unsigned len = atoi(&Hdr->name[3]);
pathname.assign(At,len);
At += len + 1; // terminated by \n
flags |= ArchiveMember::HasLongFilenameFlag;
} else
throw std::string("invalid long filename");
} else if (Hdr->name[1] == '_' &&
(0==memcmp(Hdr->name,ARFILE_LLVM_SYMTAB_NAME,16))) {
// The member is using a long file name (>15 chars) format.
// This format is standard for 4.4BSD and Mac OSX operating
// systems. LLVM uses it similarly. In this format, the
// remainder of the name field (after #1/) specifies the
// length of the file name which occupy the first bytes of
// the member's data. The pathname already has the #1/ stripped.
pathname.assign(ARFILE_LLVM_SYMTAB_NAME);
flags |= ArchiveMember::LLVMSymbolTableFlag;
}
break;
case '/':
if (Hdr->name[1]== '/') {
if (0==memcmp(Hdr->name,ARFILE_STRTAB_NAME,16)) {
pathname.assign(ARFILE_STRTAB_NAME);
flags |= ArchiveMember::StringTableFlag;
} else {
throw std::string("invalid string table name");
}
} else if (Hdr->name[1] == ' ') {
if (0==memcmp(Hdr->name,ARFILE_SYMTAB_NAME,16)) {
pathname.assign(ARFILE_SYMTAB_NAME);
flags |= ArchiveMember::ForeignSymbolTableFlag;
} else {
throw std::string("invalid foreign symbol table name");
}
} else if (isdigit(Hdr->name[1])) {
unsigned index = atoi(&Hdr->name[1]);
if (index < strtab.length()) {
const char* namep = strtab.c_str() + index;
const char* endp = strtab.c_str() + strtab.length();
const char* p = namep;
const char* last_p = p;
while (p < endp) {
if (*p == '\n' && *last_p == '/') {
pathname.assign(namep,last_p-namep);
flags |= ArchiveMember::HasLongFilenameFlag;
break;
}
last_p = p;
p++;
}
if (p >= endp)
throw std::string("missing name termiantor in string table");
} else {
throw std::string("name index beyond string table");
}
}
break;
default:
char* slash = (char*) memchr(Hdr->name,'/',16);
if (slash == 0)
throw std::string("missing name terminator");
pathname.assign(Hdr->name,slash-Hdr->name);
break;
}
// Determine if this is a bytecode file
switch (sys::IdentifyFileType(At,4)) {
case sys::BytecodeFileType:
flags |= ArchiveMember::BytecodeFlag;
break;
case sys::CompressedBytecodeFileType:
flags |= ArchiveMember::CompressedBytecodeFlag;
flags &= ~ArchiveMember::CompressedFlag;
break;
default:
flags &= ~(ArchiveMember::BytecodeFlag|
ArchiveMember::CompressedBytecodeFlag);
break;
}
// Fill in fields of the ArchiveMember
member->next = 0;
member->prev = 0;
member->parent = this;
member->path.setFile(pathname);
member->info.fileSize = MemberSize;
member->info.modTime.fromEpochTime(atoi(Hdr->date));
sscanf(Hdr->mode,"%o",&(member->info.mode));
member->info.user = atoi(Hdr->uid);
member->info.group = atoi(Hdr->gid);
member->flags = flags;
member->data = At;
return member;
}
void
Archive::checkSignature() {
// Check the magic string at file's header
if (mapfile->size() < 8 || memcmp(base, ARFILE_MAGIC,8))
throw std::string("invalid signature for an archive file");
}
// This function loads the entire archive and fully populates its ilist with
// the members of the archive file. This is typically used in preparation for
// editing the contents of the archive.
void
Archive::loadArchive() {
// Set up parsing
members.clear();
symTab.clear();
const char *At = base;
const char *End = base + mapfile->size();
checkSignature();
At += 8; // Skip the magic string.
bool seenSymbolTable = false;
bool foundFirstFile = false;
while (At < End) {
// parse the member header
const char* Save = At;
ArchiveMember* mbr = parseMemberHeader(At, End);
// check if this is the foreign symbol table
if (mbr->isForeignSymbolTable()) {
// We don't do anything with this but delete it
At += mbr->getSize();
delete mbr;
if ((int(At) & 1) == 1)
At++;
} else if (mbr->isStringTable()) {
strtab.assign(At,mbr->getSize());
At += mbr->getSize();
if ((int(At) & 1) == 1)
At++;
delete mbr;
} else if (mbr->isLLVMSymbolTable()) {
if (seenSymbolTable)
throw std::string("invalid archive: multiple symbol tables");
parseSymbolTable(mbr->getData(),mbr->getSize());
seenSymbolTable = true;
At += mbr->getSize();
if ((int(At) & 1) == 1)
At++;
delete mbr;
} else {
if (!foundFirstFile) {
firstFileOffset = Save - base;
foundFirstFile = true;
}
members.push_back(mbr);
At += mbr->getSize();
if ((int(At) & 1) == 1)
At++;
}
}
}
// Open and completely load the archive file.
Archive*
Archive::OpenAndLoad(const sys::Path& file) {
Archive* result = new Archive(file,true);
result->loadArchive();
return result;
}
// Get all the bytecode modules from the archive
bool
Archive::getAllModules(std::vector<Module*>& Modules, std::string* ErrMessage) {
for (iterator I=begin(), E=end(); I != E; ++I) {
if (I->isBytecode() || I->isCompressedBytecode()) {
Module* M = ParseBytecodeBuffer((const unsigned char*)I->getData(),
I->getSize(), I->getPath().get(), ErrMessage);
if (!M)
return true;
}
static bool ParseSymbolTableSection(unsigned char *Buffer, unsigned Size,
std::string *S) {
// Currently not supported (succeeds without doing anything)
Modules.push_back(M);
}
}
return false;
}
static bool ReadArchiveBuffer(const std::string &ArchiveName,
unsigned char *Buffer, unsigned Length,
std::vector<Module*> &Objects,
std::string *ErrorStr) {
if (Length < 8 || memcmp(Buffer, "!<arch>\n", 8))
return Error(ErrorStr, "signature incorrect for an archive file!");
Buffer += 8; Length -= 8; // Skip the magic string.
// Load just the symbol table from the archive file
void
Archive::loadSymbolTable() {
std::vector<char> LongFilenames;
// Set up parsing
members.clear();
symTab.clear();
const char *At = base;
const char *End = base + mapfile->size();
while (Length >= sizeof(ar_hdr)) {
ar_hdr *Hdr = (ar_hdr*)Buffer;
unsigned SizeFromHeader = atoi(Hdr->size);
if (SizeFromHeader + sizeof(ar_hdr) > Length)
return Error(ErrorStr, "invalid record length in archive file!");
// Make sure we're dealing with an archive
checkSignature();
unsigned char *MemberData = Buffer + sizeof(ar_hdr);
unsigned MemberSize = SizeFromHeader;
// Get name of archive member.
char *startp = Hdr->name;
char *endp = (char *) memchr (startp, '/', sizeof(ar_hdr));
if (memcmp (Hdr->name, "#1/", 3) == 0) {
// 4.4BSD/MacOSX long filenames are abbreviated as "#1/L", where L is an
// ASCII-coded decimal number representing the length of the name buffer,
// which is prepended to the archive member's contents.
unsigned NameLength = atoi (&Hdr->name[3]);
startp = (char *) MemberData;
endp = startp + NameLength;
MemberData += NameLength;
MemberSize -= NameLength;
} else if (startp == endp && isdigit (Hdr->name[1])) {
// SVR4 long filenames are abbreviated as "/I", where I is
// an ASCII-coded decimal index into the LongFilenames vector.
unsigned NameIndex = atoi (&Hdr->name[1]);
assert (LongFilenames.size () > NameIndex
&& "SVR4-style long filename for archive member not found");
startp = &LongFilenames[NameIndex];
endp = strchr (startp, '/');
} else if (startp == endp && Hdr->name[1] == '/') {
// This is for the SVR4 long filename table (there might be other
// names starting with // but I don't know about them). Make sure that
// getObjectType sees it.
endp = &Hdr->name[sizeof (Hdr->name)];
At += 8; // Skip signature
// Parse the first file member header
const char* FirstFile = At;
ArchiveMember* mbr = parseMemberHeader(At, End);
if (mbr->isForeignSymbolTable()) {
// Skip the foreign symbol table, we don't do anything with it
At += mbr->getSize();
delete mbr;
// See if there's a string table too
FirstFile = At;
mbr = parseMemberHeader(At,End);
if (mbr->isStringTable()) {
strtab.assign((const char*)mbr->getData(),mbr->getSize());
At += mbr->getSize();
delete mbr;
FirstFile = At;
mbr = parseMemberHeader(At,End);
}
if (!endp) {
// 4.4BSD/MacOSX *short* filenames are not guaranteed to have a
// terminator. Start at the end of the field and backtrack over spaces.
endp = startp + sizeof(Hdr->name);
while (endp[-1] == ' ')
--endp;
}
std::string MemberName (startp, endp);
std::string FullMemberName = ArchiveName + "(" + MemberName + ")";
switch (getObjectType(Hdr, MemberName, MemberData, MemberSize)) {
case SVR4LongFilename:
// If this is a long filename section, read all of the file names into the
// LongFilenames vector.
LongFilenames.assign (MemberData, MemberData + MemberSize);
break;
case UserObject: {
Module *M = ParseBytecodeBuffer(MemberData, MemberSize,
FullMemberName, ErrorStr);
if (!M) return true;
Objects.push_back(M);
break;
}
case ArchiveSymbolTable:
if (ParseSymbolTableSection(MemberData, MemberSize, ErrorStr))
return true;
break;
default:
std::cerr << "ReadArchiveBuffer: WARNING: Skipping unknown file: "
<< FullMemberName << "\n";
break; // Just ignore unknown files.
}
// Round SizeFromHeader up to an even number...
SizeFromHeader = (SizeFromHeader+1)/2*2;
Buffer += sizeof(ar_hdr)+SizeFromHeader; // Move to the next entry
Length -= sizeof(ar_hdr)+SizeFromHeader;
// See if its the symbol table
if (mbr->isLLVMSymbolTable()) {
parseSymbolTable(mbr->getData(),mbr->getSize());
FirstFile = At + mbr->getSize();
if (mbr->getSize() % 2 != 0)
FirstFile++;
} else {
// There's no symbol table in the file. We have to rebuild it from scratch
// because the intent of this method is to get the symbol table loaded so
// it can be searched efficiently.
// Add the member to the members list
members.push_back(mbr);
}
return Length != 0;
firstFileOffset = FirstFile - base;
}
// Open the archive and load just the symbol tables
Archive*
Archive::OpenAndLoadSymbols(const sys::Path& file) {
Archive* result = new Archive(file,true);
// ReadArchiveFile - Read bytecode files from the specified .a file, returning
// true on error, or false on success. This does not support reading files from
// standard input.
//
bool llvm::ReadArchiveFile(const std::string &Filename,
std::vector<Module*> &Objects,std::string *ErrorStr){
unsigned Length;
result->loadSymbolTable();
// mmap in the file all at once...
unsigned char *Buffer =
(unsigned char*)ReadFileIntoAddressSpace(Filename, Length);
if (Buffer == 0) {
if (ErrorStr) *ErrorStr = "Error reading file '" + Filename + "'!";
return true;
return result;
}
// Parse the archive files we mmap'ped in
bool Result = ReadArchiveBuffer(Filename, Buffer, Length, Objects, ErrorStr);
// Look up one symbol in the symbol table and return a ModuleProvider for the
// module that defines that symbol.
ModuleProvider*
Archive::findModuleDefiningSymbol(const std::string& symbol) {
SymTabType::iterator SI = symTab.find(symbol);
if (SI == symTab.end())
return 0;
// Unmmap the archive...
UnmapFileFromAddressSpace(Buffer, Length);
// The symbol table was previously constructed assuming that the members were
// written without the symbol table header. Because VBR encoding is used, the
// values could not be adjusted to account for the offset of the symbol table
// because that could affect the size of the symbol table due to VBR encoding.
// We now have to account for this by adjusting the offset by the size of the
// symbol table and its header.
unsigned fileOffset =
SI->second + // offset in symbol-table-less file
firstFileOffset; // add offset to first "real" file in archive
if (Result) // Free any loaded objects
while (!Objects.empty()) {
delete Objects.back();
Objects.pop_back();
// See if the module is already loaded
ModuleMap::iterator MI = modules.find(fileOffset);
if (MI != modules.end())
return MI->second.first;
// Module hasn't been loaded yet, we need to load it
const char* modptr = base + fileOffset;
ArchiveMember* mbr = parseMemberHeader(modptr, base + mapfile->size());
// Now, load the bytecode module to get the ModuleProvider
ModuleProvider* mp = getBytecodeBufferModuleProvider(
(const unsigned char*) mbr->getData(), mbr->getSize(),
mbr->getPath().get(), 0);
modules.insert(std::make_pair(fileOffset,std::make_pair(mp,mbr)));
return mp;
}
return Result;
// Look up multiple symbols in the symbol table and return a set of
// ModuleProviders that define those symbols.
void
Archive::findModulesDefiningSymbols(const std::set<std::string>& symbols,
std::set<ModuleProvider*>& modules)
{
for (std::set<std::string>::const_iterator I=symbols.begin(),
E=symbols.end(); I != E; ++I) {
ModuleProvider* mp = findModuleDefiningSymbol(*I);
if (mp) {
modules.insert(mp);
}
}
}

513
lib/Bytecode/Archive/ArchiveReader.cpp
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@ -1,194 +1,403 @@
//===- lib/Archive/ArchiveReader.cpp - Read LLVM archive files ------------===//
//===-- ArchiveReader.cpp - Read LLVM archive files -------------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file was developed by the LLVM research group and is distributed under
// the University of Illinois Open Source License. See LICENSE.TXT for details.
// This file was developed by Reid Spencer and is distributed under the
// University of Illinois Open Source License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements the ReadArchiveFile interface, which allows a linker to
// read all of the LLVM bytecode files contained in a .a file. This file
// understands the standard system .a file format. This can only handle the .a
// variant prevalent on Linux systems so far, but may be extended. See
// information in this source file for more information:
// http://sources.redhat.com/cgi-bin/cvsweb.cgi/src/bfd/archive.c?cvsroot=src
// Builds up standard unix archive files (.a) containing LLVM bytecode.
//
//===----------------------------------------------------------------------===//
#include "ArchiveInternals.h"
#include "llvm/Bytecode/Reader.h"
#include "llvm/Module.h"
#include "llvm/Support/FileUtilities.h"
#include <cstdlib>
#include <iostream>
using namespace llvm;
namespace {
struct ar_hdr {
char name[16];
char date[12];
char uid[6];
char gid[6];
char mode[8];
char size[10];
char fmag[2]; // Always equal to '`\n'
};
enum ObjectType {
UserObject, // A user .o/.bc file
Unknown, // Unknown file, just ignore it
SVR4LongFilename, // a "//" section used for long file names
ArchiveSymbolTable, // Symbol table produced by ranlib.
};
/// Read a variable-bit-rate encoded unsigned integer
inline unsigned readInteger(const char*&At, const char*End) {
unsigned Shift = 0;
unsigned Result = 0;
do {
if (At == End)
throw std::string("Ran out of data reading vbr_uint!");
Result |= (unsigned)((*At++) & 0x7F) << Shift;
Shift += 7;
} while (At[-1] & 0x80);
return Result;
}
/// getObjectType - Determine the type of object that this header represents.
/// This is capable of parsing the variety of special sections used for various
/// purposes.
///
static enum ObjectType getObjectType(ar_hdr *H, std::string MemberName,
unsigned char *MemberData, unsigned Size) {
// Check for sections with special names...
if (MemberName == "__.SYMDEF " || MemberName == "__.SYMDEF SORTED")
return ArchiveSymbolTable;
else if (MemberName == "// ")
return SVR4LongFilename;
// Check to see if it looks like an llvm object file...
if (Size >= 4 && !memcmp(MemberData, "llvm", 4))
return UserObject;
if (Size >= 4 && !memcmp(MemberData, "llvc", 4))
return UserObject;
return Unknown;
}
static inline bool Error(std::string *ErrorStr, const char *Message) {
if (ErrorStr) *ErrorStr = Message;
// Completely parse the Archive's symbol table and populate symTab member var.
void
Archive::parseSymbolTable(const void* data, unsigned size) {
const char* At = (const char*) data;
const char* End = At + size;
while (At < End) {
unsigned offset = readInteger(At, End);
unsigned length = readInteger(At, End);
if (At + length > End)
throw std::string("malformed symbol table");
// we don't care if it can't be inserted (duplicate entry)
symTab.insert(std::make_pair(std::string(At,length),offset));
At += length;
}
symTabSize = size;
}
// This member parses an ArchiveMemberHeader that is presumed to be pointed to
// by At. The At pointer is updated to the byte just after the header, which
// can be variable in size.
ArchiveMember*
Archive::parseMemberHeader(const char*& At, const char* End) {
assert(At + sizeof(ArchiveMemberHeader) < End && "Not enough data");
// Cast archive member header
ArchiveMemberHeader* Hdr = (ArchiveMemberHeader*)At;
At += sizeof(ArchiveMemberHeader);
// Instantiate the ArchiveMember to be filled
ArchiveMember* member = new ArchiveMember(this);
// Extract the size and determine if the file is
// compressed or not (negative length).
int flags = 0;
int MemberSize = atoi(Hdr->size);
if (MemberSize < 0) {
flags |= ArchiveMember::CompressedFlag;
MemberSize = -MemberSize;
}
// Check the size of the member for sanity
if (At + MemberSize > End)
throw std::string("invalid member length in archive file");
// Check the member signature
if (!Hdr->checkSignature())
throw std::string("invalid file member signature");
// Convert and check the member name
// The empty name ( '/' and 15 blanks) is for a foreign (non-LLVM) symbol
// table. The special name "//" and 14 blanks is for a string table, used
// for long file names. This library doesn't generate either of those but
// it will accept them. If the name starts with #1/ and the remainder is
// digits, then those digits specify the length of the name that is
// stored immediately following the header. The special name
// __LLVM_SYM_TAB__ identifies the symbol table for LLVM bytecode.
// Anything else is a regular, short filename that is terminated with
// a '/' and blanks.
std::string pathname;
unsigned index;
switch (Hdr->name[0]) {
case '#':
if (Hdr->name[1] == '1' && Hdr->name[2] == '/') {
if (isdigit(Hdr->name[3])) {
unsigned len = atoi(&Hdr->name[3]);
pathname.assign(At,len);
At += len + 1; // terminated by \n
flags |= ArchiveMember::HasLongFilenameFlag;
} else
throw std::string("invalid long filename");
} else if (Hdr->name[1] == '_' &&
(0==memcmp(Hdr->name,ARFILE_LLVM_SYMTAB_NAME,16))) {
// The member is using a long file name (>15 chars) format.
// This format is standard for 4.4BSD and Mac OSX operating
// systems. LLVM uses it similarly. In this format, the
// remainder of the name field (after #1/) specifies the
// length of the file name which occupy the first bytes of
// the member's data. The pathname already has the #1/ stripped.
pathname.assign(ARFILE_LLVM_SYMTAB_NAME);
flags |= ArchiveMember::LLVMSymbolTableFlag;
}
break;
case '/':
if (Hdr->name[1]== '/') {
if (0==memcmp(Hdr->name,ARFILE_STRTAB_NAME,16)) {
pathname.assign(ARFILE_STRTAB_NAME);
flags |= ArchiveMember::StringTableFlag;
} else {
throw std::string("invalid string table name");
}
} else if (Hdr->name[1] == ' ') {
if (0==memcmp(Hdr->name,ARFILE_SYMTAB_NAME,16)) {
pathname.assign(ARFILE_SYMTAB_NAME);
flags |= ArchiveMember::ForeignSymbolTableFlag;
} else {
throw std::string("invalid foreign symbol table name");
}
} else if (isdigit(Hdr->name[1])) {
unsigned index = atoi(&Hdr->name[1]);
if (index < strtab.length()) {
const char* namep = strtab.c_str() + index;
const char* endp = strtab.c_str() + strtab.length();
const char* p = namep;
const char* last_p = p;
while (p < endp) {
if (*p == '\n' && *last_p == '/') {
pathname.assign(namep,last_p-namep);
flags |= ArchiveMember::HasLongFilenameFlag;
break;
}
last_p = p;
p++;
}
if (p >= endp)
throw std::string("missing name termiantor in string table");
} else {
throw std::string("name index beyond string table");
}
}
break;
default:
char* slash = (char*) memchr(Hdr->name,'/',16);
if (slash == 0)
throw std::string("missing name terminator");
pathname.assign(Hdr->name,slash-Hdr->name);
break;
}
// Determine if this is a bytecode file
switch (sys::IdentifyFileType(At,4)) {
case sys::BytecodeFileType:
flags |= ArchiveMember::BytecodeFlag;
break;
case sys::CompressedBytecodeFileType:
flags |= ArchiveMember::CompressedBytecodeFlag;
flags &= ~ArchiveMember::CompressedFlag;
break;
default:
flags &= ~(ArchiveMember::BytecodeFlag|
ArchiveMember::CompressedBytecodeFlag);
break;
}
// Fill in fields of the ArchiveMember
member->next = 0;
member->prev = 0;
member->parent = this;
member->path.setFile(pathname);
member->info.fileSize = MemberSize;
member->info.modTime.fromEpochTime(atoi(Hdr->date));
sscanf(Hdr->mode,"%o",&(member->info.mode));
member->info.user = atoi(Hdr->uid);
member->info.group = atoi(Hdr->gid);
member->flags = flags;
member->data = At;
return member;
}
void
Archive::checkSignature() {
// Check the magic string at file's header
if (mapfile->size() < 8 || memcmp(base, ARFILE_MAGIC,8))
throw std::string("invalid signature for an archive file");
}
// This function loads the entire archive and fully populates its ilist with
// the members of the archive file. This is typically used in preparation for
// editing the contents of the archive.
void
Archive::loadArchive() {
// Set up parsing
members.clear();
symTab.clear();
const char *At = base;
const char *End = base + mapfile->size();
checkSignature();
At += 8; // Skip the magic string.
bool seenSymbolTable = false;
bool foundFirstFile = false;
while (At < End) {
// parse the member header
const char* Save = At;
ArchiveMember* mbr = parseMemberHeader(At, End);
// check if this is the foreign symbol table
if (mbr->isForeignSymbolTable()) {
// We don't do anything with this but delete it
At += mbr->getSize();
delete mbr;
if ((int(At) & 1) == 1)
At++;
} else if (mbr->isStringTable()) {
strtab.assign(At,mbr->getSize());
At += mbr->getSize();
if ((int(At) & 1) == 1)
At++;
delete mbr;
} else if (mbr->isLLVMSymbolTable()) {
if (seenSymbolTable)
throw std::string("invalid archive: multiple symbol tables");
parseSymbolTable(mbr->getData(),mbr->getSize());
seenSymbolTable = true;
At += mbr->getSize();
if ((int(At) & 1) == 1)
At++;
delete mbr;
} else {
if (!foundFirstFile) {
firstFileOffset = Save - base;
foundFirstFile = true;
}
members.push_back(mbr);
At += mbr->getSize();
if ((int(At) & 1) == 1)
At++;
}
}
}
// Open and completely load the archive file.
Archive*
Archive::OpenAndLoad(const sys::Path& file) {
Archive* result = new Archive(file,true);
result->loadArchive();
return result;
}
// Get all the bytecode modules from the archive
bool
Archive::getAllModules(std::vector<Module*>& Modules, std::string* ErrMessage) {
for (iterator I=begin(), E=end(); I != E; ++I) {
if (I->isBytecode() || I->isCompressedBytecode()) {
Module* M = ParseBytecodeBuffer((const unsigned char*)I->getData(),
I->getSize(), I->getPath().get(), ErrMessage);
if (!M)
return true;
}
static bool ParseSymbolTableSection(unsigned char *Buffer, unsigned Size,
std::string *S) {
// Currently not supported (succeeds without doing anything)
Modules.push_back(M);
}
}
return false;
}
static bool ReadArchiveBuffer(const std::string &ArchiveName,
unsigned char *Buffer, unsigned Length,
std::vector<Module*> &Objects,
std::string *ErrorStr) {
if (Length < 8 || memcmp(Buffer, "!<arch>\n", 8))
return Error(ErrorStr, "signature incorrect for an archive file!");
Buffer += 8; Length -= 8; // Skip the magic string.
// Load just the symbol table from the archive file
void
Archive::loadSymbolTable() {
std::vector<char> LongFilenames;
// Set up parsing
members.clear();
symTab.clear();
const char *At = base;
const char *End = base + mapfile->size();
while (Length >= sizeof(ar_hdr)) {
ar_hdr *Hdr = (ar_hdr*)Buffer;
unsigned SizeFromHeader = atoi(Hdr->size);
if (SizeFromHeader + sizeof(ar_hdr) > Length)
return Error(ErrorStr, "invalid record length in archive file!");
// Make sure we're dealing with an archive
checkSignature();
unsigned char *MemberData = Buffer + sizeof(ar_hdr);
unsigned MemberSize = SizeFromHeader;
// Get name of archive member.
char *startp = Hdr->name;
char *endp = (char *) memchr (startp, '/', sizeof(ar_hdr));
if (memcmp (Hdr->name, "#1/", 3) == 0) {
// 4.4BSD/MacOSX long filenames are abbreviated as "#1/L", where L is an
// ASCII-coded decimal number representing the length of the name buffer,
// which is prepended to the archive member's contents.
unsigned NameLength = atoi (&Hdr->name[3]);
startp = (char *) MemberData;
endp = startp + NameLength;
MemberData += NameLength;
MemberSize -= NameLength;
} else if (startp == endp && isdigit (Hdr->name[1])) {
// SVR4 long filenames are abbreviated as "/I", where I is
// an ASCII-coded decimal index into the LongFilenames vector.
unsigned NameIndex = atoi (&Hdr->name[1]);
assert (LongFilenames.size () > NameIndex
&& "SVR4-style long filename for archive member not found");
startp = &LongFilenames[NameIndex];
endp = strchr (startp, '/');
} else if (startp == endp && Hdr->name[1] == '/') {
// This is for the SVR4 long filename table (there might be other
// names starting with // but I don't know about them). Make sure that
// getObjectType sees it.
endp = &Hdr->name[sizeof (Hdr->name)];
At += 8; // Skip signature
// Parse the first file member header
const char* FirstFile = At;
ArchiveMember* mbr = parseMemberHeader(At, End);
if (mbr->isForeignSymbolTable()) {
// Skip the foreign symbol table, we don't do anything with it
At += mbr->getSize();
delete mbr;
// See if there's a string table too
FirstFile = At;
mbr = parseMemberHeader(At,End);
if (mbr->isStringTable()) {
strtab.assign((const char*)mbr->getData(),mbr->getSize());
At += mbr->getSize();
delete mbr;
FirstFile = At;
mbr = parseMemberHeader(At,End);
}
if (!endp) {
// 4.4BSD/MacOSX *short* filenames are not guaranteed to have a
// terminator. Start at the end of the field and backtrack over spaces.
endp = startp + sizeof(Hdr->name);
while (endp[-1] == ' ')
--endp;
}
std::string MemberName (startp, endp);
std::string FullMemberName = ArchiveName + "(" + MemberName + ")";
switch (getObjectType(Hdr, MemberName, MemberData, MemberSize)) {
case SVR4LongFilename:
// If this is a long filename section, read all of the file names into the
// LongFilenames vector.
LongFilenames.assign (MemberData, MemberData + MemberSize);
break;
case UserObject: {
Module *M = ParseBytecodeBuffer(MemberData, MemberSize,
FullMemberName, ErrorStr);
if (!M) return true;
Objects.push_back(M);
break;
}
case ArchiveSymbolTable:
if (ParseSymbolTableSection(MemberData, MemberSize, ErrorStr))
return true;
break;
default:
std::cerr << "ReadArchiveBuffer: WARNING: Skipping unknown file: "
<< FullMemberName << "\n";
break; // Just ignore unknown files.
}
// Round SizeFromHeader up to an even number...
SizeFromHeader = (SizeFromHeader+1)/2*2;
Buffer += sizeof(ar_hdr)+SizeFromHeader; // Move to the next entry
Length -= sizeof(ar_hdr)+SizeFromHeader;
// See if its the symbol table
if (mbr->isLLVMSymbolTable()) {
parseSymbolTable(mbr->getData(),mbr->getSize());
FirstFile = At + mbr->getSize();
if (mbr->getSize() % 2 != 0)
FirstFile++;
} else {
// There's no symbol table in the file. We have to rebuild it from scratch
// because the intent of this method is to get the symbol table loaded so
// it can be searched efficiently.
// Add the member to the members list
members.push_back(mbr);
}
return Length != 0;
firstFileOffset = FirstFile - base;
}
// Open the archive and load just the symbol tables
Archive*
Archive::OpenAndLoadSymbols(const sys::Path& file) {
Archive* result = new Archive(file,true);
// ReadArchiveFile - Read bytecode files from the specified .a file, returning
// true on error, or false on success. This does not support reading files from
// standard input.
//
bool llvm::ReadArchiveFile(const std::string &Filename,
std::vector<Module*> &Objects,std::string *ErrorStr){
unsigned Length;
result->loadSymbolTable();
// mmap in the file all at once...
unsigned char *Buffer =
(unsigned char*)ReadFileIntoAddressSpace(Filename, Length);
if (Buffer == 0) {
if (ErrorStr) *ErrorStr = "Error reading file '" + Filename + "'!";
return true;
return result;
}
// Parse the archive files we mmap'ped in
bool Result = ReadArchiveBuffer(Filename, Buffer, Length, Objects, ErrorStr);
// Look up one symbol in the symbol table and return a ModuleProvider for the
// module that defines that symbol.
ModuleProvider*
Archive::findModuleDefiningSymbol(const std::string& symbol) {
SymTabType::iterator SI = symTab.find(symbol);
if (SI == symTab.end())
return 0;
// Unmmap the archive...
UnmapFileFromAddressSpace(Buffer, Length);
// The symbol table was previously constructed assuming that the members were
// written without the symbol table header. Because VBR encoding is used, the
// values could not be adjusted to account for the offset of the symbol table
// because that could affect the size of the symbol table due to VBR encoding.
// We now have to account for this by adjusting the offset by the size of the
// symbol table and its header.
unsigned fileOffset =
SI->second + // offset in symbol-table-less file
firstFileOffset; // add offset to first "real" file in archive
if (Result) // Free any loaded objects
while (!Objects.empty()) {
delete Objects.back();
Objects.pop_back();
// See if the module is already loaded
ModuleMap::iterator MI = modules.find(fileOffset);
if (MI != modules.end())
return MI->second.first;
// Module hasn't been loaded yet, we need to load it
const char* modptr = base + fileOffset;
ArchiveMember* mbr = parseMemberHeader(modptr, base + mapfile->size());
// Now, load the bytecode module to get the ModuleProvider
ModuleProvider* mp = getBytecodeBufferModuleProvider(
(const unsigned char*) mbr->getData(), mbr->getSize(),
mbr->getPath().get(), 0);
modules.insert(std::make_pair(fileOffset,std::make_pair(mp,mbr)));
return mp;
}
return Result;
// Look up multiple symbols in the symbol table and return a set of
// ModuleProviders that define those symbols.
void
Archive::findModulesDefiningSymbols(const std::set<std::string>& symbols,
std::set<ModuleProvider*>& modules)
{
for (std::set<std::string>::const_iterator I=symbols.begin(),
E=symbols.end(); I != E; ++I) {
ModuleProvider* mp = findModuleDefiningSymbol(*I);
if (mp) {
modules.insert(mp);
}
}
}