/*************************************************************************/ /* linux_input.h */ /*************************************************************************/ /* This file is part of: */ /* PANDEMONIUM ENGINE */ /* https://github.com/Relintai/pandemonium_engine */ /*************************************************************************/ /* Copyright (c) 2022-present Péter Magyar. */ /* Copyright (c) 2014-2022 Godot Engine contributors (cf. AUTHORS.md). */ /* Copyright (c) 2007-2022 Juan Linietsky, Ariel Manzur. */ /* */ /* Permission is hereby granted, free of charge, to any person obtaining */ /* a copy of this software and associated documentation files (the */ /* "Software"), to deal in the Software without restriction, including */ /* without limitation the rights to use, copy, modify, merge, publish, */ /* distribute, sublicense, and/or sell copies of the Software, and to */ /* permit persons to whom the Software is furnished to do so, subject to */ /* the following conditions: */ /* */ /* The above copyright notice and this permission notice shall be */ /* included in all copies or substantial portions of the Software. */ /* */ /* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, */ /* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF */ /* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.*/ /* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY */ /* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, */ /* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE */ /* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ /*************************************************************************/ // linux_input.h /* * FRT - A Godot platform targeting single board computers * Copyright (c) 2017-2019 Emanuele Fornara * * Permission is hereby granted, free of charge, to any person obtaining * a copy of this software and associated documentation files (the * "Software"), to deal in the Software without restriction, including * without limitation the rights to use, copy, modify, merge, publish, * distribute, sublicense, and/or sell copies of the Software, and to * permit persons to whom the Software is furnished to do so, subject to * the following conditions: * * The above copyright notice and this permission notice shall be * included in all copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ #include #include #include #include #include #include #include namespace frt { static const char *dev_input_id_dir = "/dev/input/by-id"; enum KeyValue { KV_Released, KV_Pressed, KV_Repeated }; class LinuxInput { private: int fd; bool grabbed; bool find_by_name(char *buf, int size, const char *name) { const char *s_name = "N: Name=\""; const char *s_handlers = "H: Handlers="; const char *s_event = "event"; FILE *f = fopen("/proc/bus/input/devices", "r"); if (!f) return false; char s[1024]; bool found = false; int state = 0, nn = strlen(name), ns; while (fgets(s, sizeof(s), f) && !found) { switch (state) { case 0: if (!strncmp(s_name, s, strlen(s_name))) { ns = strlen(s); if (((int)(ns - strlen(s_name) - strlen("\"\n")) == nn) && !memcmp(&s[strlen(s_name)], name, nn)) state = 1; } break; case 1: if (!strncmp(s_handlers, s, strlen(s_handlers))) { state = 0; char *event = strstr(s, s_event); if (!event) break; int id = atoi(event + strlen(s_event)); snprintf(buf, size, "/dev/input/event%d", id); found = true; } break; } } fclose(f); return found; } bool open_file(const char *file_name) { fd = ::open(file_name, O_RDONLY | O_NONBLOCK); if (fd == -1) return false; return true; } bool parse_dir(const char *pattern, char *buf, int size) { bool found = false; DIR *dirp = opendir(dev_input_id_dir); if (!dirp) return false; while (1) { struct dirent *dp; if (!(dp = readdir(dirp))) break; const char *id = dp->d_name; if (strstr(id, pattern)) { snprintf(buf, size, "%s/%s", dev_input_id_dir, id); buf[size - 1] = '\0'; found = true; break; } } closedir(dirp); return found; } bool open_by_id_substr(const char *substr) { char buf[512]; if (!parse_dir(substr, buf, sizeof(buf))) return false; return open_file(buf); } protected: LinuxInput() : fd(-1), grabbed(false) {} bool open(const char *env_tag, const char *substr) { char *id = getenv(env_tag); if (id) { char buf[512]; const char *s = 0; if (id[0] == '/') s = id; else if (find_by_name(buf, sizeof(buf), id)) s = buf; if (s) return open_file(s); } else { return open_by_id_substr(substr); } return false; } bool grab(bool grab, int wait_ms) { /* HACK to let other clients get release keys at startup TODO: better handling */ if (this->grabbed == grab) return true; usleep(wait_ms * 1000); if (ioctl(fd, EVIOCGRAB, grab ? 1 : 0)) return false; this->grabbed = grab; return true; } void close() { if (fd != -1) { ::close(fd); fd = -1; } } bool poll() { input_event events[64]; while (1) { int bytes = read(fd, events, sizeof(events)); if (bytes <= 0) return false; int n = bytes / sizeof(input_event); for (int i = 0; i < n; i++) handle(events[i]); } } // LinuxInput virtual void handle(const input_event &ev) = 0; }; } // namespace frt