polybar/include/utils/inotify.hpp

127 lines
2.4 KiB
C++

#pragma once
#include <sys/inotify.h>
#include <sys/poll.h>
#include <cstdio>
#include "common.hpp"
#include "utils/memory.hpp"
LEMONBUDDY_NS
using inotify_event_t = struct inotify_event;
struct inotify_event {
string filename;
bool is_dir;
int wd = 0;
int cookie = 0;
int mask = 0;
};
class inotify_watch {
public:
/**
* Constructor
*/
explicit inotify_watch(string path) : m_path(path) {}
/**
* Destructor
*/
~inotify_watch() noexcept {
if (m_wd != -1)
inotify_rm_watch(m_fd, m_wd);
if (m_fd != -1)
close(m_fd);
}
/**
* Attach inotify watch
*/
void attach(int mask = IN_MODIFY) {
if (m_fd == -1 && (m_fd = inotify_init()) == -1)
throw system_error("Failed to allocate inotify fd");
if ((m_wd = inotify_add_watch(m_fd, m_path.c_str(), mask)) == -1)
throw system_error("Failed to attach inotify watch");
}
/**
* Remove inotify watch
*/
void remove() {
if (inotify_rm_watch(m_fd, m_wd) == -1)
throw system_error("Failed to remove inotify watch");
m_wd = -1;
}
/**
* Poll the inotify fd for events
*
* @brief A wait_ms of -1 blocks until an event is fired
*/
bool poll(int wait_ms = 1000) {
if (m_fd == -1)
return false;
struct pollfd fds[1];
fds[0].fd = m_fd;
fds[0].events = POLLIN;
::poll(fds, 1, wait_ms);
return fds[0].revents & POLLIN;
}
/**
* Get the latest inotify event
*/
unique_ptr<inotify_event> get_event() {
auto event = make_unique<inotify_event>();
if (m_fd == -1 || m_wd == -1)
return event;
char buffer[1024];
size_t bytes = read(m_fd, buffer, 1024);
size_t len = 0;
while (len < bytes) {
auto* e = reinterpret_cast<inotify_event_t*>(&buffer[len]);
event->filename = e->len ? e->name : m_path;
event->wd = e->wd;
event->cookie = e->cookie;
event->is_dir = e->mask & IN_ISDIR;
event->mask |= e->mask;
len += sizeof(inotify_event_t) + e->len;
}
return event;
}
/**
* Get watch file path
*/
const string path() const {
return m_path;
}
protected:
string m_path;
int m_fd = -1;
int m_wd = -1;
};
using inotify_watch_t = unique_ptr<inotify_watch>;
namespace inotify_util {
inline auto make_watch(string path) {
di::injector<inotify_watch_t> injector = di::make_injector(di::bind<>().to(path));
return injector.create<inotify_watch_t>();
};
}
LEMONBUDDY_NS_END