SDL  2.0
checkkeys.c
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1 /*
2  Copyright (C) 1997-2018 Sam Lantinga <slouken@libsdl.org>
3 
4  This software is provided 'as-is', without any express or implied
5  warranty. In no event will the authors be held liable for any damages
6  arising from the use of this software.
7 
8  Permission is granted to anyone to use this software for any purpose,
9  including commercial applications, and to alter it and redistribute it
10  freely.
11 */
12 
13 /* Simple program: Loop, watching keystrokes
14  Note that you need to call SDL_PollEvent() or SDL_WaitEvent() to
15  pump the event loop and catch keystrokes.
16 */
17 
18 #include <stdio.h>
19 #include <stdlib.h>
20 #include <string.h>
21 
22 #ifdef __EMSCRIPTEN__
23 #include <emscripten/emscripten.h>
24 #endif
25 
26 #include "SDL.h"
27 
28 int done;
29 
30 /* Call this instead of exit(), so we can clean up SDL: atexit() is evil. */
31 static void
32 quit(int rc)
33 {
34  SDL_Quit();
35  exit(rc);
36 }
37 
38 static void
39 print_string(char **text, size_t *maxlen, const char *fmt, ...)
40 {
41  int len;
42  va_list ap;
43 
44  va_start(ap, fmt);
45  len = SDL_vsnprintf(*text, *maxlen, fmt, ap);
46  if (len > 0) {
47  *text += len;
48  if ( ((size_t) len) < *maxlen ) {
49  *maxlen -= (size_t) len;
50  } else {
51  *maxlen = 0;
52  }
53  }
54  va_end(ap);
55 }
56 
57 static void
58 print_modifiers(char **text, size_t *maxlen)
59 {
60  int mod;
61  print_string(text, maxlen, " modifiers:");
62  mod = SDL_GetModState();
63  if (!mod) {
64  print_string(text, maxlen, " (none)");
65  return;
66  }
67  if (mod & KMOD_LSHIFT)
68  print_string(text, maxlen, " LSHIFT");
69  if (mod & KMOD_RSHIFT)
70  print_string(text, maxlen, " RSHIFT");
71  if (mod & KMOD_LCTRL)
72  print_string(text, maxlen, " LCTRL");
73  if (mod & KMOD_RCTRL)
74  print_string(text, maxlen, " RCTRL");
75  if (mod & KMOD_LALT)
76  print_string(text, maxlen, " LALT");
77  if (mod & KMOD_RALT)
78  print_string(text, maxlen, " RALT");
79  if (mod & KMOD_LGUI)
80  print_string(text, maxlen, " LGUI");
81  if (mod & KMOD_RGUI)
82  print_string(text, maxlen, " RGUI");
83  if (mod & KMOD_NUM)
84  print_string(text, maxlen, " NUM");
85  if (mod & KMOD_CAPS)
86  print_string(text, maxlen, " CAPS");
87  if (mod & KMOD_MODE)
88  print_string(text, maxlen, " MODE");
89 }
90 
91 static void
93 {
94  char message[512];
95  char *spot;
96  size_t left;
97 
98  spot = message;
99  left = sizeof(message);
100 
101  print_modifiers(&spot, &left);
102  SDL_Log("Initial state:%s\n", message);
103 }
104 
105 static void
106 PrintKey(SDL_Keysym * sym, SDL_bool pressed, SDL_bool repeat)
107 {
108  char message[512];
109  char *spot;
110  size_t left;
111 
112  spot = message;
113  left = sizeof(message);
114 
115  /* Print the keycode, name and state */
116  if (sym->sym) {
117  print_string(&spot, &left,
118  "Key %s: scancode %d = %s, keycode 0x%08X = %s ",
119  pressed ? "pressed " : "released",
120  sym->scancode,
122  sym->sym, SDL_GetKeyName(sym->sym));
123  } else {
124  print_string(&spot, &left,
125  "Unknown Key (scancode %d = %s) %s ",
126  sym->scancode,
128  pressed ? "pressed " : "released");
129  }
130  print_modifiers(&spot, &left);
131  if (repeat) {
132  print_string(&spot, &left, " (repeat)");
133  }
134  SDL_Log("%s\n", message);
135 }
136 
137 static void
138 PrintText(char *eventtype, char *text)
139 {
140  char *spot, expanded[1024];
141 
142  expanded[0] = '\0';
143  for ( spot = text; *spot; ++spot )
144  {
145  size_t length = SDL_strlen(expanded);
146  SDL_snprintf(expanded + length, sizeof(expanded) - length, "\\x%.2x", (unsigned char)*spot);
147  }
148  SDL_Log("%s Text (%s): \"%s%s\"\n", eventtype, expanded, *text == '"' ? "\\" : "", text);
149 }
150 
151 void
153 {
155  /* Check for events */
156  /*SDL_WaitEvent(&event); emscripten does not like waiting*/
157 
158  while (SDL_PollEvent(&event)) {
159  switch (event.type) {
160  case SDL_KEYDOWN:
161  case SDL_KEYUP:
162  PrintKey(&event.key.keysym, (event.key.state == SDL_PRESSED) ? SDL_TRUE : SDL_FALSE, (event.key.repeat) ? SDL_TRUE : SDL_FALSE);
163  break;
164  case SDL_TEXTEDITING:
165  PrintText("EDIT", event.text.text);
166  break;
167  case SDL_TEXTINPUT:
168  PrintText("INPUT", event.text.text);
169  break;
170  case SDL_MOUSEBUTTONDOWN:
171  /* Left button quits the app, other buttons toggles text input */
172  if (event.button.button == SDL_BUTTON_LEFT) {
173  done = 1;
174  } else {
175  if (SDL_IsTextInputActive()) {
176  SDL_Log("Stopping text input\n");
178  } else {
179  SDL_Log("Starting text input\n");
181  }
182  }
183  break;
184  case SDL_QUIT:
185  done = 1;
186  break;
187  default:
188  break;
189  }
190  }
191 #ifdef __EMSCRIPTEN__
192  if (done) {
193  emscripten_cancel_main_loop();
194  }
195 #endif
196 }
197 
198 int
199 main(int argc, char *argv[])
200 {
202 
203  /* Enable standard application logging */
205 
206  /* Initialize SDL */
207  if (SDL_Init(SDL_INIT_VIDEO) < 0) {
208  SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "Couldn't initialize SDL: %s\n", SDL_GetError());
209  return (1);
210  }
211 
212  /* Set 640x480 video mode */
213  window = SDL_CreateWindow("CheckKeys Test",
215  640, 480, 0);
216  if (!window) {
217  SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "Couldn't create 640x480 window: %s\n",
218  SDL_GetError());
219  quit(2);
220  }
221 
222 #if __IPHONEOS__
223  /* Creating the context creates the view, which we need to show keyboard */
224  SDL_GL_CreateContext(window);
225 #endif
226 
228 
229  /* Print initial modifier state */
230  SDL_PumpEvents();
232 
233  /* Watch keystrokes */
234  done = 0;
235 
236 #ifdef __EMSCRIPTEN__
237  emscripten_set_main_loop(loop, 0, 1);
238 #else
239  while (!done) {
240  loop();
241  }
242 #endif
243 
244  SDL_Quit();
245  return (0);
246 }
247 
248 /* vi: set ts=4 sw=4 expandtab: */
void loop()
Definition: checkkeys.c:152
#define SDL_WINDOWPOS_CENTERED
Definition: SDL_video.h:139
#define SDL_PollEvent
#define SDL_GetError
#define SDL_GL_CreateContext
GLuint GLsizei const GLchar * message
SDL_Scancode scancode
Definition: SDL_keyboard.h:49
The SDL keysym structure, used in key events.
Definition: SDL_keyboard.h:47
#define SDL_CreateWindow
GLenum GLsizei len
#define SDL_PumpEvents
#define SDL_LogError
static void PrintKey(SDL_Keysym *sym, SDL_bool pressed, SDL_bool repeat)
Definition: checkkeys.c:106
unsigned int size_t
#define SDL_Log
SDL_TextInputEvent text
Definition: SDL_events.h:532
#define SDL_vsnprintf
#define SDL_StopTextInput
char text[SDL_TEXTINPUTEVENT_TEXT_SIZE]
Definition: SDL_events.h:226
#define SDL_BUTTON_LEFT
Definition: SDL_mouse.h:282
static void quit(int rc)
Definition: checkkeys.c:32
struct _cl_event * event
#define SDL_Quit
int done
Definition: checkkeys.c:28
static void print_modifiers(char **text, size_t *maxlen)
Definition: checkkeys.c:58
SDL_Keysym keysym
Definition: SDL_events.h:199
#define SDL_StartTextInput
#define SDL_LogSetPriority
SDL_bool
Definition: SDL_stdinc.h:139
static void PrintModifierState()
Definition: checkkeys.c:92
static char text[MAX_TEXT_LENGTH]
Definition: testime.c:47
#define SDL_GetScancodeName
EGLSurface EGLNativeWindowType * window
Definition: eglext.h:1025
SDL_KeyboardEvent key
Definition: SDL_events.h:530
#define SDL_strlen
The type used to identify a window.
Definition: SDL_sysvideo.h:73
#define SDL_GetKeyName
SDL_Keycode sym
Definition: SDL_keyboard.h:50
SDL_MouseButtonEvent button
Definition: SDL_events.h:534
#define SDL_snprintf
#define SDL_Init
General event structure.
Definition: SDL_events.h:525
#define SDL_PRESSED
Definition: SDL_events.h:50
int main(int argc, char *argv[])
Definition: checkkeys.c:199
static void PrintText(char *eventtype, char *text)
Definition: checkkeys.c:138
GLuint GLsizei GLsizei * length
#define SDL_GetModState
#define SDL_IsTextInputActive
#define SDL_INIT_VIDEO
Definition: SDL.h:78
static void print_string(char **text, size_t *maxlen, const char *fmt,...)
Definition: checkkeys.c:39
Uint32 type
Definition: SDL_events.h:527
GLint left