mirror of
https://sourceware.org/git/binutils-gdb.git
synced 2025-04-12 14:33:06 +08:00
b6cc4ef6d2
My earlier patch to introduce string-set.h used the wrong type in the hash functions. This patch fixes the error.
130 lines
3.4 KiB
C++
130 lines
3.4 KiB
C++
/* String-interning set
|
|
|
|
Copyright (C) 2025 Free Software Foundation, Inc.
|
|
|
|
This file is part of GDB.
|
|
|
|
This program is free software; you can redistribute it and/or modify
|
|
it under the terms of the GNU General Public License as published by
|
|
the Free Software Foundation; either version 3 of the License, or
|
|
(at your option) any later version.
|
|
|
|
This program is distributed in the hope that it will be useful,
|
|
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
GNU General Public License for more details.
|
|
|
|
You should have received a copy of the GNU General Public License
|
|
along with this program. If not, see <http://www.gnu.org/licenses/>. */
|
|
|
|
#ifndef GDBSUPPORT_STRING_SET_H
|
|
#define GDBSUPPORT_STRING_SET_H
|
|
|
|
#include "gdbsupport/unordered_set.h"
|
|
#include <string_view>
|
|
|
|
namespace gdb
|
|
{
|
|
|
|
/* This is a string-interning set. It manages storage for strings,
|
|
ensuring that just a single copy of a given string is kept. The
|
|
underlying C string will remain valid for the lifetime of this
|
|
object. */
|
|
|
|
class string_set
|
|
{
|
|
public:
|
|
|
|
/* Insert STR into this set. Returns a pointer to the interned
|
|
string. */
|
|
const char *insert (const char *str)
|
|
{
|
|
/* We need to take the length to hash the string anyway, so it's
|
|
convenient to just wrap it here. */
|
|
return insert (std::string_view (str));
|
|
}
|
|
|
|
/* An overload accepting a string view. */
|
|
const char *insert (std::string_view str)
|
|
{
|
|
return m_set.insert (str).first->get ();
|
|
}
|
|
|
|
/* An overload that takes ownership of the string. */
|
|
const char *insert (gdb::unique_xmalloc_ptr<char> str)
|
|
{
|
|
return m_set.insert (local_string (std::move (str))).first->get ();
|
|
}
|
|
|
|
private:
|
|
|
|
/* The type of string we store. Note that we do not store
|
|
std::string here to avoid the small-string optimization
|
|
invalidating a pointer on rehash. */
|
|
struct local_string
|
|
{
|
|
explicit local_string (std::string_view str)
|
|
: contents (xstrndup (str.data (), str.size ())),
|
|
len (str.size ())
|
|
{ }
|
|
|
|
explicit local_string (gdb::unique_xmalloc_ptr<char> str)
|
|
: contents (std::move (str)),
|
|
len (strlen (contents.get ()))
|
|
{ }
|
|
|
|
const char *get () const
|
|
{ return contents.get (); }
|
|
|
|
std::string_view as_view () const
|
|
{ return std::string_view (contents.get (), len); }
|
|
|
|
/* \0-terminated string contents. */
|
|
gdb::unique_xmalloc_ptr<char> contents;
|
|
/* Length of the string. */
|
|
size_t len;
|
|
};
|
|
|
|
/* Equality object for the set. */
|
|
struct str_eq
|
|
{
|
|
using is_transparent = void;
|
|
|
|
bool operator() (std::string_view lhs, const local_string &rhs)
|
|
const noexcept
|
|
{
|
|
return lhs == rhs.as_view ();
|
|
}
|
|
|
|
bool operator() (const local_string &lhs, const local_string &rhs)
|
|
const noexcept
|
|
{
|
|
return (*this) (lhs.as_view (), rhs);
|
|
}
|
|
};
|
|
|
|
/* Hash object for the set. */
|
|
struct str_hash
|
|
{
|
|
using is_transparent = void;
|
|
using is_avalanching = void;
|
|
|
|
uint64_t operator() (const local_string &rhs) const noexcept
|
|
{
|
|
return (*this) (rhs.as_view ());
|
|
}
|
|
|
|
uint64_t operator() (std::string_view rhs) const noexcept
|
|
{
|
|
return ankerl::unordered_dense::hash<std::string_view> () (rhs);
|
|
}
|
|
};
|
|
|
|
/* The strings. */
|
|
gdb::unordered_set<local_string, str_hash, str_eq> m_set;
|
|
};
|
|
|
|
}
|
|
|
|
#endif /* GDBSUPPORT_STRING_SET_H */
|