1/*
2 Simple DirectMedia Layer
3 Copyright (C) 1997-2021 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
48 * an 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,
58 * if any
59 * \returns always -1.
60 *
61 * \sa SDL_ClearError
62 * \sa SDL_GetError
63 */
64extern DECLSPEC int SDLCALL SDL_SetError(SDL_PRINTF_FORMAT_STRING const char *fmt, ...) SDL_PRINTF_VARARG_FUNC(1);
65
66/**
67 * Retrieve a message about the last error that occurred on the current thread.
68 *
69 * It is possible for multiple errors to occur before calling SDL_GetError().
70 * Only the last error is returned.
71 *
72 * The message is only applicable when an SDL function has signaled an error.
73 * You must check the return values of SDL function calls to determine when
74 * to appropriately call SDL_GetError(). You should _not_ use the results
75 * of SDL_GetError() to decide if an error has occurred! Sometimes SDL will
76 * set an error string even when reporting success.
77 *
78 * SDL will _not_ clear the error string for successful API calls. You _must_
79 * check return values for failure cases before you can assume the error
80 * string applies.
81 *
82 * Error strings are set per-thread, so an error set in a different thread
83 * will not interfere with the current thread's operation.
84 *
85 * The returned string is internally allocated and must not be freed by the
86 * application.
87 *
88 * \returns a message with information about the specific error that occurred,
89 * or an empty string if there hasn't been an error message set since
90 * the last call to SDL_ClearError(). The message is only applicable when an
91 * SDL function has signaled an error. You must check the return
92 * values of SDL function calls to determine when to appropriately
93 * call SDL_GetError().
94 *
95 * \sa SDL_ClearError
96 * \sa SDL_SetError
97 */
98extern DECLSPEC const char *SDLCALL SDL_GetError(void);
99
100/**
101 * Get the last error message that was set for the current thread.
102 *
103 * This allows the caller to copy the error string into a provided buffer,
104 * but otherwise operates exactly the same as SDL_GetError().
105 *
106 * \param errstr A buffer to fill with the last error message that was set
107 * for the current thread
108 * \param maxlen The size of the buffer pointed to by the errstr parameter
109 * \returns The pointer passed in as the `errstr` parameter.
110 *
111 * \sa SDL_GetError
112 */
113extern DECLSPEC char * SDLCALL SDL_GetErrorMsg(char *errstr, int maxlen);
114
115/**
116 * Clear any previous error message for this thread.
117 *
118 * \sa SDL_GetError
119 * \sa SDL_SetError
120 */
121extern DECLSPEC void SDLCALL SDL_ClearError(void);
122
123/**
124 * \name Internal error functions
125 *
126 * \internal
127 * Private error reporting function - used internally.
128 */
129/* @{ */
130#define SDL_OutOfMemory() SDL_Error(SDL_ENOMEM)
131#define SDL_Unsupported() SDL_Error(SDL_UNSUPPORTED)
132#define SDL_InvalidParamError(param) SDL_SetError("Parameter '%s' is invalid", (param))
133typedef enum
134{
135 SDL_ENOMEM,
136 SDL_EFREAD,
137 SDL_EFWRITE,
138 SDL_EFSEEK,
139 SDL_UNSUPPORTED,
140 SDL_LASTERROR
141} SDL_errorcode;
142/* SDL_Error() unconditionally returns -1. */
143extern DECLSPEC int SDLCALL SDL_Error(SDL_errorcode code);
144/* @} *//* Internal error functions */
145
146/* Ends C function definitions when using C++ */
147#ifdef __cplusplus
148}
149#endif
150#include "close_code.h"
151
152#endif /* SDL_error_h_ */
153
154/* vi: set ts=4 sw=4 expandtab: */
155