/* Copyright (C) 1997-2022 Sam Lantinga <slouken@libsdl.org> This software is provided 'as-is', without any express or implied warranty. In no event will the authors be held liable for any damages arising from the use of this software. Permission is granted to anyone to use this software for any purpose, including commercial applications, and to alter it and redistribute it freely. */ /* Simple program: Loop, watching keystrokes Note that you need to call SDL_PollEvent() or SDL_WaitEvent() to pump the event loop and catch keystrokes. */ #include <stdio.h> #include <stdlib.h> #include <string.h> #ifdef __EMSCRIPTEN__ #include <emscripten/emscripten.h> #endif #include "SDL.h" int done; /* Call this instead of exit(), so we can clean up SDL: atexit() is evil. */ static void quit(int rc) { SDL_Quit(); exit(rc); } static void print_string(char **text, size_t *maxlen, const char *fmt, ...) { int len; va_list ap; va_start(ap, fmt); len = SDL_vsnprintf(*text, *maxlen, fmt, ap); if (len > 0) { *text += len; if ( ((size_t) len) < *maxlen ) { *maxlen -= (size_t) len; } else { *maxlen = 0; } } va_end(ap); } static void print_modifiers(char **text, size_t *maxlen) { int mod; print_string(text, maxlen, " modifiers:"); mod = SDL_GetModState(); if (!mod) { print_string(text, maxlen, " (none)"); return; } if (mod & KMOD_LSHIFT) print_string(text, maxlen, " LSHIFT"); if (mod & KMOD_RSHIFT) print_string(text, maxlen, " RSHIFT"); if (mod & KMOD_LCTRL) print_string(text, maxlen, " LCTRL"); if (mod & KMOD_RCTRL) print_string(text, maxlen, " RCTRL"); if (mod & KMOD_LALT) print_string(text, maxlen, " LALT"); if (mod & KMOD_RALT) print_string(text, maxlen, " RALT"); if (mod & KMOD_LGUI) print_string(text, maxlen, " LGUI"); if (mod & KMOD_RGUI) print_string(text, maxlen, " RGUI"); if (mod & KMOD_NUM) print_string(text, maxlen, " NUM"); if (mod & KMOD_CAPS) print_string(text, maxlen, " CAPS"); if (mod & KMOD_MODE) print_string(text, maxlen, " MODE"); if (mod & KMOD_SCROLL) print_string(text, maxlen, " SCROLL"); } static void PrintModifierState() { char message[512]; char *spot; size_t left; spot = message; left = sizeof(message); print_modifiers(&spot, &left); SDL_Log("Initial state:%s\n", message); } static void PrintKey(SDL_Keysym * sym, SDL_bool pressed, SDL_bool repeat) { char message[512]; char *spot; size_t left; spot = message; left = sizeof(message); /* Print the keycode, name and state */ if (sym->sym) { print_string(&spot, &left, "Key %s: scancode %d = %s, keycode 0x%08X = %s ", pressed ? "pressed " : "released", sym->scancode, SDL_GetScancodeName(sym->scancode), sym->sym, SDL_GetKeyName(sym->sym)); } else { print_string(&spot, &left, "Unknown Key (scancode %d = %s) %s ", sym->scancode, SDL_GetScancodeName(sym->scancode), pressed ? "pressed " : "released"); } print_modifiers(&spot, &left); if (repeat) { print_string(&spot, &left, " (repeat)"); } SDL_Log("%s\n", message); fflush(stderr); } static void PrintText(const char *eventtype, const char *text) { const char *spot; char expanded[1024]; expanded[0] = '\0'; for ( spot = text; *spot; ++spot ) { size_t length = SDL_strlen(expanded); SDL_snprintf(expanded + length, sizeof(expanded) - length, "\\x%.2x", (unsigned char)*spot); } SDL_Log("%s Text (%s): \"%s%s\"\n", eventtype, expanded, *text == '"' ? "\\" : "", text); } void loop() { SDL_Event event; /* Check for events */ /*SDL_WaitEvent(&event); emscripten does not like waiting*/ fprintf(stderr, "starting loop\n"); fflush(stderr); // while (SDL_PollEvent(&event)) { while (!done && SDL_WaitEvent(&event)) { fprintf(stderr, "got event type: %" SDL_PRIu32 "\n", event.type); fflush(stderr); switch (event.type) { case SDL_KEYDOWN: case SDL_KEYUP: PrintKey(&event.key.keysym, (event.key.state == SDL_PRESSED) ? SDL_TRUE : SDL_FALSE, (event.key.repeat) ? SDL_TRUE : SDL_FALSE); break; case SDL_TEXTEDITING: PrintText("EDIT", event.text.text); break; case SDL_TEXTINPUT: PrintText("INPUT", event.text.text); break; case SDL_MOUSEBUTTONDOWN: /* Left button quits the app, other buttons toggles text input */ fprintf(stderr, "mouse button down button: %d (LEFT=%d)\n", event.button.button, SDL_BUTTON_LEFT); fflush(stderr); if (event.button.button == SDL_BUTTON_LEFT) { done = 1; } else { if (SDL_IsTextInputActive()) { SDL_Log("Stopping text input\n"); SDL_StopTextInput(); } else { SDL_Log("Starting text input\n"); SDL_StartTextInput(); } } break; case SDL_QUIT: done = 1; break; default: break; } fprintf(stderr, "waiting new event\n"); fflush(stderr); } fprintf(stderr, "exiting event loop\n"); fflush(stderr); #ifdef __EMSCRIPTEN__ if (done) { emscripten_cancel_main_loop(); } #endif } /* Very simple thread - counts 0 to 9 delaying 50ms between increments */ static int SDLCALL ping_thread(void *ptr) { int cnt; SDL_Event sdlevent; SDL_memset(&sdlevent, 0 , sizeof(SDL_Event)); for (cnt = 0; cnt < 10; ++cnt) { fprintf(stderr, "sending event (%d/%d) from thread.\n", cnt + 1, 10); fflush(stderr); sdlevent.type = SDL_KEYDOWN; sdlevent.key.keysym.sym = SDLK_1; SDL_PushEvent(&sdlevent); SDL_Delay(1000 + rand() % 1000); } return cnt; } int main(int argc, char *argv[]) { SDL_Window *window; SDL_Renderer *renderer; SDL_Thread *thread; /* Enable standard application logging */ SDL_LogSetPriority(SDL_LOG_CATEGORY_APPLICATION, SDL_LOG_PRIORITY_INFO); /* Initialize SDL */ if (SDL_Init(SDL_INIT_VIDEO) < 0) { SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "Couldn't initialize SDL: %s\n", SDL_GetError()); return (1); } /* Set 640x480 video mode */ window = SDL_CreateWindow("CheckKeys Test", SDL_WINDOWPOS_CENTERED, SDL_WINDOWPOS_CENTERED, 640, 480, 0); if (!window) { SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "Couldn't create 640x480 window: %s\n", SDL_GetError()); quit(2); } /* On wayland, no window will actually show until something has actually been displayed. */ renderer = SDL_CreateRenderer(window, -1, 0); SDL_RenderPresent(renderer); #if __IPHONEOS__ /* Creating the context creates the view, which we need to show keyboard */ SDL_GL_CreateContext(window); #endif SDL_StartTextInput(); /* Print initial modifier state */ SDL_PumpEvents(); PrintModifierState(); /* Watch keystrokes */ done = 0; thread = SDL_CreateThread(ping_thread, "PingThread", (void *)NULL); #ifdef __EMSCRIPTEN__ emscripten_set_main_loop(loop, 0, 1); #else while (!done) { loop(); } #endif SDL_WaitThread(thread, NULL); SDL_Quit(); return (0); } /* vi: set ts=4 sw=4 expandtab: */