include/SDL_keyboard.h
author David Ludwig <dludwig@pobox.com>
Sat, 29 Nov 2014 10:09:30 -0500
changeset 9247 eddb899239fe
parent 8149 681eb46b8ac4
child 9619 b94b6d0bff0f
permissions -rw-r--r--
WinRT: bug and data-integrity fixes for SDL_GetPrefPath()

This change does a few things, all with regards to the WinRT implementation of
SDL_GetPrefPath():

1. it fixes a bug whereby SDL_GetPrefPath() did not create the directory it
returned. On other SDL platforms, SDL_GetPrefPath() will create separate
directories for its 'org' and 'app' folders. Without this, attempts to create
files in the pref-path would fail, unless those directories were first created
by the app, or by some other library the app used. This change makes sure
that these directories get created, before SDL_GetPrefPath() returns to its
caller(s).


2. it defaults to having SDL_GetPrefPath() return a WinRT 'Local' folder
on all platforms. Previously, for Windows Store apps, it would have used a
different, 'Roaming' folder. Files in Roaming folders can be automatically,
and synchronized across multiple devices by Windows. This synchronization can
happen while the app runs, with new files being copied into a running app's
pref-path. Unless an app is specifically designed to handle this scenario,
there is a chance that save-data could be overwritten in unwanted or
unexpected ways.

The default is now to use a Local folder, which does not get synchronized, and
which is arguably a bit safer to use. Apps that wish to use Roaming folders
can do so by setting SDL_HINT_WINRT_PREF_PATH_ROOT to "roaming", however it
is recommended that one first read Microsoft's documentation for Roaming
files, a link to which is provided in README-winrt.md.

To preserve older pref-path selection behavior (found in SDL 2.0.3, as well as
many pre-2.0.4 versions of SDL from hg.libsdl.org), which uses a Roaming path
in Windows Store apps, and a Local path in Windows Phone, set
SDL_HINT_WINRT_PREF_PATH_ROOT to "old".

Please note that Roaming paths are not supported on Windows Phone 8.0, due to
limitations in the OS itself. Attempts to use this will fail.
(Windows Phone 8.1 does not have this limitation, however.)


3. It makes SDL_GetPrefPath(), when on Windows Phone 8.0, and when
SDL_HINT_WINRT_PREF_PATH_ROOT is set to "roaming", return NULL, rather than
silently defaulting to a Local path (then switching to a Roaming path if and
when the user upgraded to Windows Phone 8.1).
     1 /*
     2   Simple DirectMedia Layer
     3   Copyright (C) 1997-2014 Sam Lantinga <slouken@libsdl.org>
     4 
     5   This software is provided 'as-is', without any express or implied
     6   warranty.  In no event will the authors be held liable for any damages
     7   arising from the use of this software.
     8 
     9   Permission is granted to anyone to use this software for any purpose,
    10   including commercial applications, and to alter it and redistribute it
    11   freely, subject to the following restrictions:
    12 
    13   1. The origin of this software must not be misrepresented; you must not
    14      claim that you wrote the original software. If you use this software
    15      in a product, an acknowledgment in the product documentation would be
    16      appreciated but is not required.
    17   2. Altered source versions must be plainly marked as such, and must not be
    18      misrepresented as being the original software.
    19   3. This notice may not be removed or altered from any source distribution.
    20 */
    21 
    22 /**
    23  *  \file SDL_keyboard.h
    24  *
    25  *  Include file for SDL keyboard event handling
    26  */
    27 
    28 #ifndef _SDL_keyboard_h
    29 #define _SDL_keyboard_h
    30 
    31 #include "SDL_stdinc.h"
    32 #include "SDL_error.h"
    33 #include "SDL_keycode.h"
    34 #include "SDL_video.h"
    35 
    36 #include "begin_code.h"
    37 /* Set up for C function definitions, even when using C++ */
    38 #ifdef __cplusplus
    39 extern "C" {
    40 #endif
    41 
    42 /**
    43  *  \brief The SDL keysym structure, used in key events.
    44  *
    45  *  \note  If you are looking for translated character input, see the ::SDL_TEXTINPUT event.
    46  */
    47 typedef struct SDL_Keysym
    48 {
    49     SDL_Scancode scancode;      /**< SDL physical key code - see ::SDL_Scancode for details */
    50     SDL_Keycode sym;            /**< SDL virtual key code - see ::SDL_Keycode for details */
    51     Uint16 mod;                 /**< current key modifiers */
    52     Uint32 unused;
    53 } SDL_Keysym;
    54 
    55 /* Function prototypes */
    56 
    57 /**
    58  *  \brief Get the window which currently has keyboard focus.
    59  */
    60 extern DECLSPEC SDL_Window * SDLCALL SDL_GetKeyboardFocus(void);
    61 
    62 /**
    63  *  \brief Get a snapshot of the current state of the keyboard.
    64  *
    65  *  \param numkeys if non-NULL, receives the length of the returned array.
    66  *
    67  *  \return An array of key states. Indexes into this array are obtained by using ::SDL_Scancode values.
    68  *
    69  *  \b Example:
    70  *  \code
    71  *  const Uint8 *state = SDL_GetKeyboardState(NULL);
    72  *  if ( state[SDL_SCANCODE_RETURN] )   {
    73  *      printf("<RETURN> is pressed.\n");
    74  *  }
    75  *  \endcode
    76  */
    77 extern DECLSPEC const Uint8 *SDLCALL SDL_GetKeyboardState(int *numkeys);
    78 
    79 /**
    80  *  \brief Get the current key modifier state for the keyboard.
    81  */
    82 extern DECLSPEC SDL_Keymod SDLCALL SDL_GetModState(void);
    83 
    84 /**
    85  *  \brief Set the current key modifier state for the keyboard.
    86  *
    87  *  \note This does not change the keyboard state, only the key modifier flags.
    88  */
    89 extern DECLSPEC void SDLCALL SDL_SetModState(SDL_Keymod modstate);
    90 
    91 /**
    92  *  \brief Get the key code corresponding to the given scancode according
    93  *         to the current keyboard layout.
    94  *
    95  *  See ::SDL_Keycode for details.
    96  *
    97  *  \sa SDL_GetKeyName()
    98  */
    99 extern DECLSPEC SDL_Keycode SDLCALL SDL_GetKeyFromScancode(SDL_Scancode scancode);
   100 
   101 /**
   102  *  \brief Get the scancode corresponding to the given key code according to the
   103  *         current keyboard layout.
   104  *
   105  *  See ::SDL_Scancode for details.
   106  *
   107  *  \sa SDL_GetScancodeName()
   108  */
   109 extern DECLSPEC SDL_Scancode SDLCALL SDL_GetScancodeFromKey(SDL_Keycode key);
   110 
   111 /**
   112  *  \brief Get a human-readable name for a scancode.
   113  *
   114  *  \return A pointer to the name for the scancode.
   115  *          If the scancode doesn't have a name, this function returns
   116  *          an empty string ("").
   117  *
   118  *  \sa SDL_Scancode
   119  */
   120 extern DECLSPEC const char *SDLCALL SDL_GetScancodeName(SDL_Scancode scancode);
   121 
   122 /**
   123  *  \brief Get a scancode from a human-readable name
   124  *
   125  *  \return scancode, or SDL_SCANCODE_UNKNOWN if the name wasn't recognized
   126  *
   127  *  \sa SDL_Scancode
   128  */
   129 extern DECLSPEC SDL_Scancode SDLCALL SDL_GetScancodeFromName(const char *name);
   130 
   131 /**
   132  *  \brief Get a human-readable name for a key.
   133  *
   134  *  \return A pointer to a UTF-8 string that stays valid at least until the next
   135  *          call to this function. If you need it around any longer, you must
   136  *          copy it.  If the key doesn't have a name, this function returns an
   137  *          empty string ("").
   138  *
   139  *  \sa SDL_Key
   140  */
   141 extern DECLSPEC const char *SDLCALL SDL_GetKeyName(SDL_Keycode key);
   142 
   143 /**
   144  *  \brief Get a key code from a human-readable name
   145  *
   146  *  \return key code, or SDLK_UNKNOWN if the name wasn't recognized
   147  *
   148  *  \sa SDL_Keycode
   149  */
   150 extern DECLSPEC SDL_Keycode SDLCALL SDL_GetKeyFromName(const char *name);
   151 
   152 /**
   153  *  \brief Start accepting Unicode text input events.
   154  *         This function will show the on-screen keyboard if supported.
   155  *
   156  *  \sa SDL_StopTextInput()
   157  *  \sa SDL_SetTextInputRect()
   158  *  \sa SDL_HasScreenKeyboardSupport()
   159  */
   160 extern DECLSPEC void SDLCALL SDL_StartTextInput(void);
   161 
   162 /**
   163  *  \brief Return whether or not Unicode text input events are enabled.
   164  *
   165  *  \sa SDL_StartTextInput()
   166  *  \sa SDL_StopTextInput()
   167  */
   168 extern DECLSPEC SDL_bool SDLCALL SDL_IsTextInputActive(void);
   169 
   170 /**
   171  *  \brief Stop receiving any text input events.
   172  *         This function will hide the on-screen keyboard if supported.
   173  *
   174  *  \sa SDL_StartTextInput()
   175  *  \sa SDL_HasScreenKeyboardSupport()
   176  */
   177 extern DECLSPEC void SDLCALL SDL_StopTextInput(void);
   178 
   179 /**
   180  *  \brief Set the rectangle used to type Unicode text inputs.
   181  *         This is used as a hint for IME and on-screen keyboard placement.
   182  *
   183  *  \sa SDL_StartTextInput()
   184  */
   185 extern DECLSPEC void SDLCALL SDL_SetTextInputRect(SDL_Rect *rect);
   186 
   187 /**
   188  *  \brief Returns whether the platform has some screen keyboard support.
   189  *
   190  *  \return SDL_TRUE if some keyboard support is available else SDL_FALSE.
   191  *
   192  *  \note Not all screen keyboard functions are supported on all platforms.
   193  *
   194  *  \sa SDL_IsScreenKeyboardShown()
   195  */
   196 extern DECLSPEC SDL_bool SDLCALL SDL_HasScreenKeyboardSupport(void);
   197 
   198 /**
   199  *  \brief Returns whether the screen keyboard is shown for given window.
   200  *
   201  *  \param window The window for which screen keyboard should be queried.
   202  *
   203  *  \return SDL_TRUE if screen keyboard is shown else SDL_FALSE.
   204  *
   205  *  \sa SDL_HasScreenKeyboardSupport()
   206  */
   207 extern DECLSPEC SDL_bool SDLCALL SDL_IsScreenKeyboardShown(SDL_Window *window);
   208 
   209 /* Ends C function definitions when using C++ */
   210 #ifdef __cplusplus
   211 }
   212 #endif
   213 #include "close_code.h"
   214 
   215 #endif /* _SDL_keyboard_h */
   216 
   217 /* vi: set ts=4 sw=4 expandtab: */