portability: abstract memfd_create away

This commit is contained in:
Raphael Robatsch 2021-11-16 19:30:16 +01:00
parent 4b54d4b3d1
commit f257340432
3 changed files with 38 additions and 3 deletions

View file

@ -42,6 +42,7 @@ extern zwlr_layer_shell_v1* wlrLayerShell;
void spawn(Monitor&, const Arg& arg); void spawn(Monitor&, const Arg& arg);
void setCloexec(int fd); void setCloexec(int fd);
[[noreturn]] void die(const char* why); [[noreturn]] void die(const char* why);
[[noreturn]] void diesys(const char* why);
// wayland smart pointers // wayland smart pointers
template<typename T> template<typename T>

View file

@ -62,7 +62,6 @@ static void onGlobalRemove(void*, wl_registry* registry, uint32_t name);
static void requireGlobal(const void* p, const char* name); static void requireGlobal(const void* p, const char* name);
static void waylandFlush(); static void waylandFlush();
static void cleanup(); static void cleanup();
[[noreturn]] static void diesys(const char* why);
wl_display* display; wl_display* display;
wl_compositor* compositor; wl_compositor* compositor;

View file

@ -1,11 +1,14 @@
// somebar - dwl bar // somebar - dwl bar
// See LICENSE file for copyright and license details. // See LICENSE file for copyright and license details.
#include <fcntl.h>
#include <sys/mman.h> #include <sys/mman.h>
#include <sys/stat.h>
#include <unistd.h> #include <unistd.h>
#include "shm_buffer.hpp" #include "shm_buffer.hpp"
#include "common.hpp" #include "common.hpp"
static int createAnonShm();
constexpr int n = 2; constexpr int n = 2;
ShmBuffer::ShmBuffer(int w, int h, wl_shm_format format) ShmBuffer::ShmBuffer(int w, int h, wl_shm_format format)
@ -15,8 +18,13 @@ ShmBuffer::ShmBuffer(int w, int h, wl_shm_format format)
{ {
auto oneSize = stride*size_t(h); auto oneSize = stride*size_t(h);
auto totalSize = oneSize * n; auto totalSize = oneSize * n;
auto fd = memfd_create("wl_shm", MFD_CLOEXEC); auto fd = createAnonShm();
ftruncate(fd, totalSize); if (fd < 0) {
diesys("memfd_create");
}
if (ftruncate(fd, totalSize) < 0) {
diesys("ftruncate");
}
auto pool = wl_shm_create_pool(shm, fd, totalSize); auto pool = wl_shm_create_pool(shm, fd, totalSize);
auto ptr = reinterpret_cast<uint8_t*>(mmap(nullptr, totalSize, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0)); auto ptr = reinterpret_cast<uint8_t*>(mmap(nullptr, totalSize, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0));
_mapping = MemoryMapping {ptr, totalSize}; _mapping = MemoryMapping {ptr, totalSize};
@ -34,3 +42,30 @@ ShmBuffer::ShmBuffer(int w, int h, wl_shm_format format)
uint8_t* ShmBuffer::data() { return _buffers[_current].data; } uint8_t* ShmBuffer::data() { return _buffers[_current].data; }
wl_buffer* ShmBuffer::buffer() { return _buffers[_current].buffer.get(); } wl_buffer* ShmBuffer::buffer() { return _buffers[_current].buffer.get(); }
void ShmBuffer::flip() { _current = 1-_current; } void ShmBuffer::flip() { _current = 1-_current; }
#if defined(__linux__)
static int createAnonShm() {
return memfd_create("wl_shm", MFD_CLOEXEC);
}
#elif defined(__FreeBSD__)
static int createAnonShm() {
auto fd = shm_open(SHM_ANON, O_CREAT | O_RDWR, 0600);
setCloexec(fd);
return fd;
}
#elif defined(__OpenBSD__)
static int createAnonShm() {
char name[] = "/wl_shm-XXXXXX";
auto fd = shm_mkstemp(name);
if (fd >= 0) {
auto res = shm_unlink(name);
if (res < 0) {
return res;
}
}
setCloexec(fd);
return fd;
}
#else
#error "your system has no sane method of creating an anonymous shared memory object. no, calling shm_open in a loop is not sane."
#endif