Mercurial > sdl-ios-xcode
diff src/SDL_hints.c @ 5192:6f6a9340fb93
Added a hint system to allow configuration hints to be specified by the application.
author | Sam Lantinga <slouken@libsdl.org> |
---|---|
date | Sat, 05 Feb 2011 10:02:39 -0800 |
parents | |
children | 01bced9a4cc1 |
line wrap: on
line diff
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/src/SDL_hints.c Sat Feb 05 10:02:39 2011 -0800 @@ -0,0 +1,115 @@ +/* + SDL - Simple DirectMedia Layer + Copyright (C) 1997-2010 Sam Lantinga + + This library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + This library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with this library; if not, write to the Free Software + Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + + Sam Lantinga + slouken@libsdl.org +*/ +#include "SDL_config.h" + +#include "SDL_hints.h" + + +/* Assuming there aren't many hints set and they aren't being queried in + critical performance paths, we'll just use a linked list here. + */ +typedef struct SDL_Hint { + char *name; + char *value; + SDL_HintPriority priority; + struct SDL_Hint *next; +} SDL_Hint; + +static SDL_Hint *SDL_hints; + + +SDL_bool +SDL_SetHint(const char *name, const char *value, SDL_HintPriority priority) +{ + const char *env; + SDL_Hint *prev, *hint; + + if (!name || !value) { + return SDL_FALSE; + } + + env = SDL_getenv(name); + if (env && priority < SDL_HINT_OVERRIDE) { + return SDL_FALSE; + } + + prev = NULL; + for (hint = SDL_hints; hint; prev = hint, hint = hint->next) { + if (SDL_strcmp(name, hint->name) == 0) { + if (priority < hint->priority) { + return SDL_FALSE; + } + if (SDL_strcmp(hint->value, value) != 0) { + SDL_free(hint->value); + hint->value = SDL_strdup(value); + } + hint->priority = priority; + return SDL_TRUE; + } + } + + /* Couldn't find the hint, add a new one */ + hint = (SDL_Hint *)SDL_malloc(sizeof(*hint)); + if (!hint) { + return SDL_FALSE; + } + hint->name = SDL_strdup(name); + hint->value = SDL_strdup(value); + hint->priority = priority; + hint->next = SDL_hints; + SDL_hints = hint; + return SDL_TRUE; +} + +const char * +SDL_GetHint(const char *name) +{ + const char *env; + SDL_Hint *hint; + + env = SDL_getenv(name); + for (hint = SDL_hints; hint; hint = hint->next) { + if (SDL_strcmp(name, hint->name) == 0) { + if (!env || hint->priority == SDL_HINT_OVERRIDE) { + return hint->value; + } + break; + } + } + return env; +} + +void SDL_ClearHints() +{ + SDL_Hint *hint; + + while (SDL_hints) { + hint = SDL_hints; + SDL_hints = hint->next; + + SDL_free(hint->name); + SDL_free(hint->value); + SDL_free(hint); + } +} + +/* vi: set ts=4 sw=4 expandtab: */