teak-llvm/lldb/source/Core/ConstString.cpp
Greg Clayton 24756648e5 Fixed up the comments in the headerdoc to match the current implementation
of how ConstString objects work, and removed the duplicate and out of date
comments that were in the cpp file.

llvm-svn: 139487
2011-09-12 03:55:58 +00:00

297 lines
8.7 KiB
C++

//===-- ConstString.cpp -----------------------------------------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#include "lldb/Core/ConstString.h"
#include "lldb/Core/Stream.h"
#include "lldb/Host/Mutex.h"
#include "llvm/ADT/StringMap.h"
using namespace lldb_private;
class Pool
{
public:
typedef const char * StringPoolValueType;
typedef llvm::StringMap<StringPoolValueType, llvm::BumpPtrAllocator> StringPool;
typedef llvm::StringMapEntry<StringPoolValueType> StringPoolEntryType;
//------------------------------------------------------------------
// Default constructor
//
// Initialize the member variables and create the empty string.
//------------------------------------------------------------------
Pool () :
m_mutex (Mutex::eMutexTypeRecursive),
m_string_map ()
{
}
//------------------------------------------------------------------
// Destructor
//------------------------------------------------------------------
~Pool ()
{
}
static StringPoolEntryType &
GetStringMapEntryFromKeyData (const char *keyData)
{
char *ptr = const_cast<char*>(keyData) - sizeof (StringPoolEntryType);
return *reinterpret_cast<StringPoolEntryType*>(ptr);
}
size_t
GetConstCStringLength (const char *ccstr) const
{
if (ccstr)
{
const StringPoolEntryType&entry = GetStringMapEntryFromKeyData (ccstr);
return entry.getKey().size();
}
return 0;
}
StringPoolValueType
GetMangledCounterpart (const char *ccstr) const
{
if (ccstr)
return GetStringMapEntryFromKeyData (ccstr).getValue();
return 0;
}
bool
SetMangledCounterparts (const char *key_ccstr, const char *value_ccstr)
{
if (key_ccstr && value_ccstr)
{
GetStringMapEntryFromKeyData (key_ccstr).setValue(value_ccstr);
GetStringMapEntryFromKeyData (value_ccstr).setValue(key_ccstr);
return true;
}
return false;
}
const char *
GetConstCString (const char *cstr)
{
if (cstr)
return GetConstCStringWithLength (cstr, strlen (cstr));
return NULL;
}
const char *
GetConstCStringWithLength (const char *cstr, int cstr_len)
{
if (cstr)
{
Mutex::Locker locker (m_mutex);
llvm::StringRef string_ref (cstr, cstr_len);
StringPoolEntryType& entry = m_string_map.GetOrCreateValue (string_ref, (StringPoolValueType)NULL);
return entry.getKeyData();
}
return NULL;
}
const char *
GetConstCStringAndSetMangledCounterPart (const char *demangled_cstr, const char *mangled_ccstr)
{
if (demangled_cstr)
{
Mutex::Locker locker (m_mutex);
// Make string pool entry with the mangled counterpart already set
StringPoolEntryType& entry = m_string_map.GetOrCreateValue (llvm::StringRef (demangled_cstr), mangled_ccstr);
// Extract the const version of the demangled_cstr
const char *demangled_ccstr = entry.getKeyData();
// Now assign the demangled const string as the counterpart of the
// mangled const string...
GetStringMapEntryFromKeyData (mangled_ccstr).setValue(demangled_ccstr);
// Return the constant demangled C string
return demangled_ccstr;
}
return NULL;
}
const char *
GetConstTrimmedCStringWithLength (const char *cstr, int cstr_len)
{
if (cstr)
{
int trimmed_len = std::min<int> (strlen (cstr), cstr_len);
return GetConstCStringWithLength (cstr, trimmed_len);
}
return NULL;
}
//------------------------------------------------------------------
// Return the size in bytes that this object and any items in its
// collection of uniqued strings + data count values takes in
// memory.
//------------------------------------------------------------------
size_t
MemorySize() const
{
Mutex::Locker locker (m_mutex);
size_t mem_size = sizeof(Pool);
const_iterator end = m_string_map.end();
for (const_iterator pos = m_string_map.begin(); pos != end; ++pos)
{
mem_size += sizeof(StringPoolEntryType) + pos->getKey().size();
}
return mem_size;
}
protected:
//------------------------------------------------------------------
// Typedefs
//------------------------------------------------------------------
typedef StringPool::iterator iterator;
typedef StringPool::const_iterator const_iterator;
//------------------------------------------------------------------
// Member variables
//------------------------------------------------------------------
mutable Mutex m_mutex;
StringPool m_string_map;
};
//----------------------------------------------------------------------
// Frameworks and dylibs aren't supposed to have global C++
// initializers so we hide the string pool in a static function so
// that it will get initialized on the first call to this static
// function.
//----------------------------------------------------------------------
static Pool &
StringPool()
{
static Pool string_pool;
return string_pool;
}
ConstString::ConstString (const char *cstr) :
m_string (StringPool().GetConstCString (cstr))
{
}
ConstString::ConstString (const char *cstr, size_t cstr_len) :
m_string (StringPool().GetConstCStringWithLength (cstr, cstr_len))
{
}
bool
ConstString::operator < (const ConstString& rhs) const
{
if (m_string == rhs.m_string)
return false;
llvm::StringRef lhs_string_ref (m_string, StringPool().GetConstCStringLength (m_string));
llvm::StringRef rhs_string_ref (rhs.m_string, StringPool().GetConstCStringLength (rhs.m_string));
// If both have valid C strings, then return the comparison
if (lhs_string_ref.data() && rhs_string_ref.data())
return lhs_string_ref < rhs_string_ref;
// Else one of them was NULL, so if LHS is NULL then it is less than
return lhs_string_ref.data() == NULL;
}
Stream&
lldb_private::operator << (Stream& s, const ConstString& str)
{
const char *cstr = str.GetCString();
if (cstr)
s << cstr;
return s;
}
size_t
ConstString::GetLength () const
{
return StringPool().GetConstCStringLength (m_string);
}
int
ConstString::Compare (const ConstString& lhs, const ConstString& rhs)
{
// If the iterators are the same, this is the same string
register const char *lhs_cstr = lhs.m_string;
register const char *rhs_cstr = rhs.m_string;
if (lhs_cstr == rhs_cstr)
return 0;
if (lhs_cstr && rhs_cstr)
{
llvm::StringRef lhs_string_ref (lhs_cstr, StringPool().GetConstCStringLength (lhs_cstr));
llvm::StringRef rhs_string_ref (rhs_cstr, StringPool().GetConstCStringLength (rhs_cstr));
return lhs_string_ref.compare(rhs_string_ref);
}
if (lhs_cstr)
return +1; // LHS isn't NULL but RHS is
else
return -1; // LHS is NULL but RHS isn't
}
void
ConstString::Dump(Stream *s, const char *fail_value) const
{
const char *cstr = AsCString (fail_value);
if (cstr)
s->PutCString (cstr);
}
void
ConstString::DumpDebug(Stream *s) const
{
const char *cstr = GetCString ();
size_t cstr_len = GetLength();
// Only print the parens if we have a non-NULL string
const char *parens = cstr ? "\"" : "";
s->Printf("%*p: ConstString, string = %s%s%s, length = %zu", (int)sizeof(void*) * 2, this, parens, cstr, parens, cstr_len);
}
void
ConstString::SetCString (const char *cstr)
{
m_string = StringPool().GetConstCString (cstr);
}
void
ConstString::SetCStringWithMangledCounterpart (const char *demangled, const ConstString &mangled)
{
m_string = StringPool().GetConstCStringAndSetMangledCounterPart (demangled, mangled.m_string);
}
bool
ConstString::GetMangledCounterpart (ConstString &counterpart) const
{
counterpart.m_string = StringPool().GetMangledCounterpart(m_string);
return counterpart;
}
void
ConstString::SetCStringWithLength (const char *cstr, size_t cstr_len)
{
m_string = StringPool().GetConstCStringWithLength(cstr, cstr_len);
}
void
ConstString::SetTrimmedCStringWithLength (const char *cstr, size_t cstr_len)
{
m_string = StringPool().GetConstTrimmedCStringWithLength (cstr, cstr_len);
}
size_t
ConstString::StaticMemorySize()
{
// Get the size of the static string pool
return StringPool().MemorySize();
}