SDL  2.0
checkkeys.c
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1 /*
2  Copyright (C) 1997-2016 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  /* Any button press quits the app... */
172  case SDL_QUIT:
173  done = 1;
174  break;
175  default:
176  break;
177  }
178  }
179 #ifdef __EMSCRIPTEN__
180  if (done) {
181  emscripten_cancel_main_loop();
182  }
183 #endif
184 }
185 
186 int
187 main(int argc, char *argv[])
188 {
190 
191  /* Enable standard application logging */
193 
194  /* Initialize SDL */
195  if (SDL_Init(SDL_INIT_VIDEO) < 0) {
196  SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "Couldn't initialize SDL: %s\n", SDL_GetError());
197  return (1);
198  }
199 
200  /* Set 640x480 video mode */
201  window = SDL_CreateWindow("CheckKeys Test",
203  640, 480, 0);
204  if (!window) {
205  SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "Couldn't create 640x480 window: %s\n",
206  SDL_GetError());
207  quit(2);
208  }
209 
210 #if __IPHONEOS__
211  /* Creating the context creates the view, which we need to show keyboard */
212  SDL_GL_CreateContext(window);
213 #endif
214 
216 
217  /* Print initial modifier state */
218  SDL_PumpEvents();
220 
221  /* Watch keystrokes */
222  done = 0;
223 
224 #ifdef __EMSCRIPTEN__
225  emscripten_set_main_loop(loop, 0, 1);
226 #else
227  while (!done) {
228  loop();
229  }
230 #endif
231 
232  SDL_Quit();
233  return (0);
234 }
235 
236 /* vi: set ts=4 sw=4 expandtab: */
void loop()
Definition: checkkeys.c:152
#define SDL_WINDOWPOS_CENTERED
Definition: SDL_video.h:129
#define SDL_PollEvent
#define SDL_GetError
#define SDL_GL_CreateContext
GLuint GLsizei const GLchar * message
SDL_Window * window
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
SDL_bool
Definition: SDL_stdinc.h:126
unsigned int size_t
#define SDL_Log
SDL_TextInputEvent text
Definition: SDL_events.h:528
#define SDL_vsnprintf
char text[SDL_TEXTINPUTEVENT_TEXT_SIZE]
Definition: SDL_events.h:223
GLint left
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:196
#define SDL_StartTextInput
#define SDL_LogSetPriority
static void PrintModifierState()
Definition: checkkeys.c:92
static char text[MAX_TEXT_LENGTH]
Definition: testime.c:34
#define SDL_GetScancodeName
SDL_KeyboardEvent key
Definition: SDL_events.h:526
#define SDL_strlen
The type used to identify a window.
Definition: SDL_sysvideo.h:71
#define SDL_GetKeyName
SDL_Keycode sym
Definition: SDL_keyboard.h:50
#define SDL_snprintf
#define SDL_Init
General event structure.
Definition: SDL_events.h:521
#define SDL_PRESSED
Definition: SDL_events.h:50
int main(int argc, char *argv[])
Definition: checkkeys.c:187
static void PrintText(char *eventtype, char *text)
Definition: checkkeys.c:138
GLuint GLsizei GLsizei * length
#define SDL_GetModState
#define SDL_INIT_VIDEO
Definition: SDL.h:77
static void print_string(char **text, size_t *maxlen, const char *fmt,...)
Definition: checkkeys.c:39
Uint32 type
Definition: SDL_events.h:523