mirror of
https://github.com/SerenityOS/serenity
synced 2024-09-06 00:51:33 +00:00
218 lines
5.8 KiB
C++
218 lines
5.8 KiB
C++
/*
|
|
* Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
|
|
* All rights reserved.
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions are met:
|
|
*
|
|
* 1. Redistributions of source code must retain the above copyright notice, this
|
|
* list of conditions and the following disclaimer.
|
|
*
|
|
* 2. Redistributions in binary form must reproduce the above copyright notice,
|
|
* this list of conditions and the following disclaimer in the documentation
|
|
* and/or other materials provided with the distribution.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
|
|
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
|
|
* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
|
|
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
|
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
|
|
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
|
|
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
|
|
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
|
|
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
|
|
*/
|
|
|
|
#if defined(__serenity__) || defined(__linux__)
|
|
|
|
# include <AK/SharedBuffer.h>
|
|
# include <AK/kmalloc.h>
|
|
# include <Kernel/API/Syscall.h>
|
|
# include <stdio.h>
|
|
|
|
# if defined(__serenity__)
|
|
# include <serenity.h>
|
|
# elif defined(__linux__)
|
|
# include <AK/String.h>
|
|
# include <fcntl.h>
|
|
# include <sys/mman.h>
|
|
|
|
static String shbuf_shm_name(int shbuf_id)
|
|
{
|
|
return String::formatted("/serenity-shm:{}", shbuf_id);
|
|
}
|
|
|
|
# endif
|
|
|
|
namespace AK {
|
|
|
|
RefPtr<SharedBuffer> SharedBuffer::create_with_size(int size)
|
|
{
|
|
# if defined(__serenity__)
|
|
void* data;
|
|
int shbuf_id = shbuf_create(size, &data);
|
|
if (shbuf_id < 0) {
|
|
perror("shbuf_create");
|
|
return nullptr;
|
|
}
|
|
# elif defined(__linux__)
|
|
// Not atomic, so don't create shared buffers from many threads too hard under lagom.
|
|
static unsigned g_shm_id = 0;
|
|
|
|
int shbuf_id = (getpid() << 8) | (g_shm_id++);
|
|
int fd = shm_open(shbuf_shm_name(shbuf_id).characters(), O_RDWR | O_CREAT | O_EXCL, S_IRUSR | S_IWUSR);
|
|
if (fd < 0) {
|
|
perror("shm_open");
|
|
return nullptr;
|
|
}
|
|
|
|
if (ftruncate(fd, size) < 0) {
|
|
perror("ftruncate");
|
|
return nullptr;
|
|
}
|
|
|
|
void* data = mmap(nullptr, size + sizeof(size_t), PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
|
|
if (data == MAP_FAILED) {
|
|
perror("mmap");
|
|
return nullptr;
|
|
}
|
|
size_t* size_data = reinterpret_cast<size_t*>(data);
|
|
*size_data = size;
|
|
data = reinterpret_cast<u8*>(data) + sizeof(size_t);
|
|
|
|
if (close(fd) < 0) {
|
|
perror("close");
|
|
return nullptr;
|
|
}
|
|
# endif
|
|
return adopt(*new SharedBuffer(shbuf_id, size, data));
|
|
}
|
|
|
|
bool SharedBuffer::share_with(pid_t peer)
|
|
{
|
|
# if defined(__serenity__)
|
|
int ret = shbuf_allow_pid(shbuf_id(), peer);
|
|
if (ret < 0) {
|
|
perror("shbuf_allow_pid");
|
|
return false;
|
|
}
|
|
# else
|
|
(void)peer;
|
|
# endif
|
|
return true;
|
|
}
|
|
|
|
bool SharedBuffer::share_globally()
|
|
{
|
|
# if defined(__serenity__)
|
|
int ret = shbuf_allow_all(shbuf_id());
|
|
if (ret < 0) {
|
|
perror("shbuf_allow_all");
|
|
return false;
|
|
}
|
|
# endif
|
|
return true;
|
|
}
|
|
|
|
RefPtr<SharedBuffer> SharedBuffer::create_from_shbuf_id(int shbuf_id)
|
|
{
|
|
# if defined(__serenity__)
|
|
size_t size = 0;
|
|
void* data = shbuf_get(shbuf_id, &size);
|
|
if (data == (void*)-1)
|
|
return nullptr;
|
|
# elif defined(__linux__)
|
|
int fd = shm_open(shbuf_shm_name(shbuf_id).characters(), O_RDWR, S_IRUSR | S_IWUSR);
|
|
if (fd < 0) {
|
|
perror("shm_open");
|
|
return nullptr;
|
|
}
|
|
|
|
void* data = mmap(nullptr, sizeof(size_t), PROT_READ, MAP_SHARED, fd, 0);
|
|
if (data == MAP_FAILED) {
|
|
perror("mmap");
|
|
return nullptr;
|
|
}
|
|
size_t* size_data = reinterpret_cast<size_t*>(data);
|
|
size_t size = *size_data;
|
|
if (munmap(data, sizeof(size_t)) < 0) {
|
|
perror("munmap");
|
|
return nullptr;
|
|
}
|
|
|
|
data = mmap(nullptr, size + sizeof(size_t), PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
|
|
if (data == MAP_FAILED) {
|
|
perror("mmap");
|
|
return nullptr;
|
|
}
|
|
|
|
data = reinterpret_cast<u8*>(data) + sizeof(size_t);
|
|
|
|
if (close(fd) < 0) {
|
|
perror("close");
|
|
return nullptr;
|
|
}
|
|
# endif
|
|
|
|
return adopt(*new SharedBuffer(shbuf_id, size, data));
|
|
}
|
|
|
|
SharedBuffer::SharedBuffer(int shbuf_id, int size, void* data)
|
|
: m_shbuf_id(shbuf_id)
|
|
, m_size(size)
|
|
, m_data(data)
|
|
{
|
|
}
|
|
|
|
SharedBuffer::~SharedBuffer()
|
|
{
|
|
if (m_shbuf_id >= 0) {
|
|
# if defined(__serenity__)
|
|
int rc = shbuf_release(m_shbuf_id);
|
|
if (rc < 0) {
|
|
perror("shbuf_release");
|
|
}
|
|
# elif defined(__linux__)
|
|
if (munmap(reinterpret_cast<u8*>(m_data) - sizeof(size_t), m_size + sizeof(size_t)) < 0)
|
|
perror("munmap");
|
|
if (shm_unlink(shbuf_shm_name(m_shbuf_id).characters()) < 0)
|
|
perror("unlink");
|
|
# endif
|
|
}
|
|
}
|
|
|
|
void SharedBuffer::seal()
|
|
{
|
|
# if defined(__serenity__)
|
|
int rc = shbuf_seal(m_shbuf_id);
|
|
if (rc < 0) {
|
|
perror("shbuf_seal");
|
|
ASSERT_NOT_REACHED();
|
|
}
|
|
# endif
|
|
}
|
|
|
|
void SharedBuffer::set_volatile()
|
|
{
|
|
# if defined(__serenity__)
|
|
u32 rc = syscall(SC_shbuf_set_volatile, m_shbuf_id, true);
|
|
ASSERT(rc == 0);
|
|
# endif
|
|
}
|
|
|
|
bool SharedBuffer::set_nonvolatile()
|
|
{
|
|
# if defined(__serenity__)
|
|
u32 rc = syscall(SC_shbuf_set_volatile, m_shbuf_id, false);
|
|
if (rc == 0)
|
|
return true;
|
|
ASSERT(rc == 1);
|
|
# endif
|
|
return false;
|
|
}
|
|
|
|
}
|
|
|
|
#endif
|