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Diffstat (limited to 'gdbsupport/ptid.h')
-rw-r--r-- | gdbsupport/ptid.h | 155 |
1 files changed, 155 insertions, 0 deletions
diff --git a/gdbsupport/ptid.h b/gdbsupport/ptid.h new file mode 100644 index 0000000..ef52d55 --- /dev/null +++ b/gdbsupport/ptid.h @@ -0,0 +1,155 @@ +/* The ptid_t type and common functions operating on it. + + Copyright (C) 1986-2020 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 COMMON_PTID_H +#define COMMON_PTID_H + +/* The ptid struct is a collection of the various "ids" necessary for + identifying the inferior process/thread being debugged. This + consists of the process id (pid), lightweight process id (lwp) and + thread id (tid). When manipulating ptids, the constructors, + accessors, and predicates declared in this file should be used. Do + NOT access the struct ptid members directly. + + process_stratum targets that handle threading themselves should + prefer using the ptid.lwp field, leaving the ptid.tid field for any + thread_stratum target that might want to sit on top. +*/ + +class ptid_t +{ +public: + /* Must have a trivial defaulted default constructor so that the + type remains POD. */ + ptid_t () noexcept = default; + + /* Make a ptid given the necessary PID, LWP, and TID components. + + A ptid with only a PID (LWP and TID equal to zero) is usually used to + represent a whole process, including all its lwps/threads. */ + + explicit constexpr ptid_t (int pid, long lwp = 0, long tid = 0) + : m_pid (pid), m_lwp (lwp), m_tid (tid) + {} + + /* Fetch the pid (process id) component from the ptid. */ + + constexpr int pid () const + { return m_pid; } + + /* Return true if the ptid's lwp member is non-zero. */ + + constexpr bool lwp_p () const + { return m_lwp != 0; } + + /* Fetch the lwp (lightweight process) component from the ptid. */ + + constexpr long lwp () const + { return m_lwp; } + + /* Return true if the ptid's tid member is non-zero. */ + + constexpr bool tid_p () const + { return m_tid != 0; } + + /* Fetch the tid (thread id) component from a ptid. */ + + constexpr long tid () const + { return m_tid; } + + /* Return true if the ptid represents a whole process, including all its + lwps/threads. Such ptids have the form of (pid, 0, 0), with + pid != -1. */ + + constexpr bool is_pid () const + { + return (*this != make_null () + && *this != make_minus_one () + && m_lwp == 0 + && m_tid == 0); + } + + /* Compare two ptids to see if they are equal. */ + + constexpr bool operator== (const ptid_t &other) const + { + return (m_pid == other.m_pid + && m_lwp == other.m_lwp + && m_tid == other.m_tid); + } + + /* Compare two ptids to see if they are different. */ + + constexpr bool operator!= (const ptid_t &other) const + { + return !(*this == other); + } + + /* Return true if the ptid matches FILTER. FILTER can be the wild + card MINUS_ONE_PTID (all ptids match it); can be a ptid representing + a process (ptid.is_pid () returns true), in which case, all lwps and + threads of that given process match, lwps and threads of other + processes do not; or, it can represent a specific thread, in which + case, only that thread will match true. The ptid must represent a + specific LWP or THREAD, it can never be a wild card. */ + + constexpr bool matches (const ptid_t &filter) const + { + return (/* If filter represents any ptid, it's always a match. */ + filter == make_minus_one () + /* If filter is only a pid, any ptid with that pid + matches. */ + || (filter.is_pid () && m_pid == filter.pid ()) + + /* Otherwise, this ptid only matches if it's exactly equal + to filter. */ + || *this == filter); + } + + /* Make a null ptid. */ + + static constexpr ptid_t make_null () + { return ptid_t (0, 0, 0); } + + /* Make a minus one ptid. */ + + static constexpr ptid_t make_minus_one () + { return ptid_t (-1, 0, 0); } + +private: + /* Process id. */ + int m_pid; + + /* Lightweight process id. */ + long m_lwp; + + /* Thread id. */ + long m_tid; +}; + +/* The null or zero ptid, often used to indicate no process. */ + +extern const ptid_t null_ptid; + +/* The (-1,0,0) ptid, often used to indicate either an error condition + or a "don't care" condition, i.e, "run all threads." */ + +extern const ptid_t minus_one_ptid; + +#endif /* COMMON_PTID_H */ |