1/*
2 Simple DirectMedia Layer
3 Copyright (C) 1997-2022 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_error.h
24 *
25 * Simple error message routines for SDL.
26 */
27
28#ifndef SDL_error_h_
29#define SDL_error_h_
30
31#include "SDL_stdinc.h"
32
33#include "begin_code.h"
34/* Set up for C function definitions, even when using C++ */
35#ifdef __cplusplus
36extern "C" {
37#endif
38
39/* Public functions */
40
41
42/**
43 * Set the SDL error message for the current thread.
44 *
45 * Calling this function will replace any previous error message that was set.
46 *
47 * This function always returns -1, since SDL frequently uses -1 to signify an
48 * failing result, leading to this idiom:
49 *
50 * ```c
51 * if (error_code) {
52 * return SDL_SetError("This operation has failed: %d", error_code);
53 * }
54 * ```
55 *
56 * \param fmt a printf()-style message format string
57 * \param ... additional parameters matching % tokens in the `fmt` string, if
58 * any
59 * \returns always -1.
60 *
61 * \since This function is available since SDL 2.0.0.
62 *
63 * \sa SDL_ClearError
64 * \sa SDL_GetError
65 */
66extern DECLSPEC int SDLCALL SDL_SetError(SDL_PRINTF_FORMAT_STRING const char *fmt, ...) SDL_PRINTF_VARARG_FUNC(1);
67
68/**
69 * Retrieve a message about the last error that occurred on the current
70 * thread.
71 *
72 * It is possible for multiple errors to occur before calling SDL_GetError().
73 * Only the last error is returned.
74 *
75 * The message is only applicable when an SDL function has signaled an error.
76 * You must check the return values of SDL function calls to determine when to
77 * appropriately call SDL_GetError(). You should *not* use the results of
78 * SDL_GetError() to decide if an error has occurred! Sometimes SDL will set
79 * an error string even when reporting success.
80 *
81 * SDL will *not* clear the error string for successful API calls. You *must*
82 * check return values for failure cases before you can assume the error
83 * string applies.
84 *
85 * Error strings are set per-thread, so an error set in a different thread
86 * will not interfere with the current thread's operation.
87 *
88 * The returned string is internally allocated and must not be freed by the
89 * application.
90 *
91 * \returns a message with information about the specific error that occurred,
92 * or an empty string if there hasn't been an error message set since
93 * the last call to SDL_ClearError(). The message is only applicable
94 * when an SDL function has signaled an error. You must check the
95 * return values of SDL function calls to determine when to
96 * appropriately call SDL_GetError().
97 *
98 * \since This function is available since SDL 2.0.0.
99 *
100 * \sa SDL_ClearError
101 * \sa SDL_SetError
102 */
103extern DECLSPEC const char *SDLCALL SDL_GetError(void);
104
105/**
106 * Get the last error message that was set for the current thread.
107 *
108 * This allows the caller to copy the error string into a provided buffer, but
109 * otherwise operates exactly the same as SDL_GetError().
110 *
111 * \param errstr A buffer to fill with the last error message that was set for
112 * the current thread
113 * \param maxlen The size of the buffer pointed to by the errstr parameter
114 * \returns the pointer passed in as the `errstr` parameter.
115 *
116 * \since This function is available since SDL 2.0.14.
117 *
118 * \sa SDL_GetError
119 */
120extern DECLSPEC char * SDLCALL SDL_GetErrorMsg(char *errstr, int maxlen);
121
122/**
123 * Clear any previous error message for this thread.
124 *
125 * \since This function is available since SDL 2.0.0.
126 *
127 * \sa SDL_GetError
128 * \sa SDL_SetError
129 */
130extern DECLSPEC void SDLCALL SDL_ClearError(void);
131
132/**
133 * \name Internal error functions
134 *
135 * \internal
136 * Private error reporting function - used internally.
137 */
138/* @{ */
139#define SDL_OutOfMemory() SDL_Error(SDL_ENOMEM)
140#define SDL_Unsupported() SDL_Error(SDL_UNSUPPORTED)
141#define SDL_InvalidParamError(param) SDL_SetError("Parameter '%s' is invalid", (param))
142typedef enum
143{
144 SDL_ENOMEM,
145 SDL_EFREAD,
146 SDL_EFWRITE,
147 SDL_EFSEEK,
148 SDL_UNSUPPORTED,
149 SDL_LASTERROR
150} SDL_errorcode;
151/* SDL_Error() unconditionally returns -1. */
152extern DECLSPEC int SDLCALL SDL_Error(SDL_errorcode code);
153/* @} *//* Internal error functions */
154
155/* Ends C function definitions when using C++ */
156#ifdef __cplusplus
157}
158#endif
159#include "close_code.h"
160
161#endif /* SDL_error_h_ */
162
163/* vi: set ts=4 sw=4 expandtab: */
164