| /* |
| Simple DirectMedia Layer |
| Copyright (C) 1997-2023 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, subject to the following restrictions: |
| |
| 1. The origin of this software must not be misrepresented; you must not |
| claim that you wrote the original software. If you use this software |
| in a product, an acknowledgment in the product documentation would be |
| appreciated but is not required. |
| 2. Altered source versions must be plainly marked as such, and must not be |
| misrepresented as being the original software. |
| 3. This notice may not be removed or altered from any source distribution. |
| */ |
| #include "./SDL_internal.h" |
| |
| #include "SDL_hints.h" |
| #include "SDL_error.h" |
| #include "SDL_hints_c.h" |
| |
| /* Assuming there aren't many hints set and they aren't being queried in |
| critical performance paths, we'll just use linked lists here. |
| */ |
| typedef struct SDL_HintWatch |
| { |
| SDL_HintCallback callback; |
| void *userdata; |
| struct SDL_HintWatch *next; |
| } SDL_HintWatch; |
| |
| typedef struct SDL_Hint |
| { |
| char *name; |
| char *value; |
| SDL_HintPriority priority; |
| SDL_HintWatch *callbacks; |
| struct SDL_Hint *next; |
| } SDL_Hint; |
| |
| static SDL_Hint *SDL_hints; |
| |
| SDL_bool SDL_SetHintWithPriority(const char *name, const char *value, SDL_HintPriority priority) |
| { |
| const char *env; |
| SDL_Hint *hint; |
| SDL_HintWatch *entry; |
| |
| if (name == NULL) { |
| return SDL_FALSE; |
| } |
| |
| env = SDL_getenv(name); |
| if (env && priority < SDL_HINT_OVERRIDE) { |
| return SDL_FALSE; |
| } |
| |
| for (hint = SDL_hints; hint; hint = hint->next) { |
| if (SDL_strcmp(name, hint->name) == 0) { |
| if (priority < hint->priority) { |
| return SDL_FALSE; |
| } |
| if (hint->value != value && |
| (value == NULL || !hint->value || SDL_strcmp(hint->value, value) != 0)) { |
| for (entry = hint->callbacks; entry;) { |
| /* Save the next entry in case this one is deleted */ |
| SDL_HintWatch *next = entry->next; |
| entry->callback(entry->userdata, name, hint->value, value); |
| entry = next; |
| } |
| SDL_free(hint->value); |
| hint->value = value ? SDL_strdup(value) : NULL; |
| } |
| hint->priority = priority; |
| return SDL_TRUE; |
| } |
| } |
| |
| /* Couldn't find the hint, add a new one */ |
| hint = (SDL_Hint *)SDL_malloc(sizeof(*hint)); |
| if (hint == NULL) { |
| return SDL_FALSE; |
| } |
| hint->name = SDL_strdup(name); |
| hint->value = value ? SDL_strdup(value) : NULL; |
| hint->priority = priority; |
| hint->callbacks = NULL; |
| hint->next = SDL_hints; |
| SDL_hints = hint; |
| return SDL_TRUE; |
| } |
| |
| SDL_bool SDL_ResetHint(const char *name) |
| { |
| const char *env; |
| SDL_Hint *hint; |
| SDL_HintWatch *entry; |
| |
| if (name == NULL) { |
| return SDL_FALSE; |
| } |
| |
| env = SDL_getenv(name); |
| for (hint = SDL_hints; hint; hint = hint->next) { |
| if (SDL_strcmp(name, hint->name) == 0) { |
| if ((env == NULL && hint->value != NULL) || |
| (env != NULL && hint->value == NULL) || |
| (env != NULL && SDL_strcmp(env, hint->value) != 0)) { |
| for (entry = hint->callbacks; entry;) { |
| /* Save the next entry in case this one is deleted */ |
| SDL_HintWatch *next = entry->next; |
| entry->callback(entry->userdata, name, hint->value, env); |
| entry = next; |
| } |
| } |
| SDL_free(hint->value); |
| hint->value = NULL; |
| hint->priority = SDL_HINT_DEFAULT; |
| return SDL_TRUE; |
| } |
| } |
| return SDL_FALSE; |
| } |
| |
| void SDL_ResetHints(void) |
| { |
| const char *env; |
| SDL_Hint *hint; |
| SDL_HintWatch *entry; |
| |
| for (hint = SDL_hints; hint; hint = hint->next) { |
| env = SDL_getenv(hint->name); |
| if ((env == NULL && hint->value != NULL) || |
| (env != NULL && hint->value == NULL) || |
| (env != NULL && SDL_strcmp(env, hint->value) != 0)) { |
| for (entry = hint->callbacks; entry;) { |
| /* Save the next entry in case this one is deleted */ |
| SDL_HintWatch *next = entry->next; |
| entry->callback(entry->userdata, hint->name, hint->value, env); |
| entry = next; |
| } |
| } |
| SDL_free(hint->value); |
| hint->value = NULL; |
| hint->priority = SDL_HINT_DEFAULT; |
| } |
| } |
| |
| SDL_bool SDL_SetHint(const char *name, const char *value) |
| { |
| return SDL_SetHintWithPriority(name, value, SDL_HINT_NORMAL); |
| } |
| |
| 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 == NULL || hint->priority == SDL_HINT_OVERRIDE) { |
| return hint->value; |
| } |
| break; |
| } |
| } |
| return env; |
| } |
| |
| SDL_bool SDL_GetStringBoolean(const char *value, SDL_bool default_value) |
| { |
| if (value == NULL || !*value) { |
| return default_value; |
| } |
| if (*value == '0' || SDL_strcasecmp(value, "false") == 0) { |
| return SDL_FALSE; |
| } |
| return SDL_TRUE; |
| } |
| |
| SDL_bool SDL_GetHintBoolean(const char *name, SDL_bool default_value) |
| { |
| const char *hint = SDL_GetHint(name); |
| return SDL_GetStringBoolean(hint, default_value); |
| } |
| |
| void SDL_AddHintCallback(const char *name, SDL_HintCallback callback, void *userdata) |
| { |
| SDL_Hint *hint; |
| SDL_HintWatch *entry; |
| const char *value; |
| |
| if (name == NULL || !*name) { |
| SDL_InvalidParamError("name"); |
| return; |
| } |
| if (!callback) { |
| SDL_InvalidParamError("callback"); |
| return; |
| } |
| |
| SDL_DelHintCallback(name, callback, userdata); |
| |
| entry = (SDL_HintWatch *)SDL_malloc(sizeof(*entry)); |
| if (entry == NULL) { |
| SDL_OutOfMemory(); |
| return; |
| } |
| entry->callback = callback; |
| entry->userdata = userdata; |
| |
| for (hint = SDL_hints; hint; hint = hint->next) { |
| if (SDL_strcmp(name, hint->name) == 0) { |
| break; |
| } |
| } |
| if (hint == NULL) { |
| /* Need to add a hint entry for this watcher */ |
| hint = (SDL_Hint *)SDL_malloc(sizeof(*hint)); |
| if (hint == NULL) { |
| SDL_OutOfMemory(); |
| SDL_free(entry); |
| return; |
| } |
| hint->name = SDL_strdup(name); |
| if (!hint->name) { |
| SDL_free(entry); |
| SDL_free(hint); |
| SDL_OutOfMemory(); |
| return; |
| } |
| hint->value = NULL; |
| hint->priority = SDL_HINT_DEFAULT; |
| hint->callbacks = NULL; |
| hint->next = SDL_hints; |
| SDL_hints = hint; |
| } |
| |
| /* Add it to the callbacks for this hint */ |
| entry->next = hint->callbacks; |
| hint->callbacks = entry; |
| |
| /* Now call it with the current value */ |
| value = SDL_GetHint(name); |
| callback(userdata, name, value, value); |
| } |
| |
| void SDL_DelHintCallback(const char *name, SDL_HintCallback callback, void *userdata) |
| { |
| SDL_Hint *hint; |
| SDL_HintWatch *entry, *prev; |
| |
| for (hint = SDL_hints; hint; hint = hint->next) { |
| if (SDL_strcmp(name, hint->name) == 0) { |
| prev = NULL; |
| for (entry = hint->callbacks; entry; entry = entry->next) { |
| if (callback == entry->callback && userdata == entry->userdata) { |
| if (prev) { |
| prev->next = entry->next; |
| } else { |
| hint->callbacks = entry->next; |
| } |
| SDL_free(entry); |
| break; |
| } |
| prev = entry; |
| } |
| return; |
| } |
| } |
| } |
| |
| void SDL_ClearHints(void) |
| { |
| SDL_Hint *hint; |
| SDL_HintWatch *entry; |
| |
| while (SDL_hints) { |
| hint = SDL_hints; |
| SDL_hints = hint->next; |
| |
| SDL_free(hint->name); |
| SDL_free(hint->value); |
| for (entry = hint->callbacks; entry;) { |
| SDL_HintWatch *freeable = entry; |
| entry = entry->next; |
| SDL_free(freeable); |
| } |
| SDL_free(hint); |
| } |
| } |
| |
| /* vi: set ts=4 sw=4 expandtab: */ |