SDL/src/SDL_error.c
Ryan C. Gordon 09ca66bf66 SDL_error: simplified error string management.
This patch removes deferred error string formatting: now we do it during
SDL_SetError(), so there's no limit on printf-style arguments used.

Also removes stub for managing error string translations; we don't have the
facilities to maintain that and the way we set arbitrary error strings
doesn't really make this practical anyhow.

Since the final error string is set right away and unique to the thread,
we no longer need a static buffer for legacy SDL_GetError(), and we don't
have to allocate 5x 128-byte argument fields per-thread. Also, since we now
use SDL_vsnprintf instead of parsing the format string ourselves, there's a
lot of code deleted and we have access to more robust formatting powers now.

This does mean the final error strings can't be more than 128 bytes, down
from the theoretical maximum of around 768, but I think this is probably okay.
They might truncate but they will always be null-terminated!

Fixes Bugzilla #5092.
2020-04-21 01:30:36 -04:00

120 lines
3.1 KiB
C

/*
Simple DirectMedia Layer
Copyright (C) 1997-2020 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"
/* Simple error handling in SDL */
#include "SDL_error.h"
#include "SDL_error_c.h"
#define SDL_ERRBUFIZE 1024
int
SDL_SetError(SDL_PRINTF_FORMAT_STRING const char *fmt, ...)
{
/* Ignore call if invalid format pointer was passed */
if (fmt != NULL) {
va_list ap;
SDL_error *error = SDL_GetErrBuf();
error->error = 1; /* mark error as valid */
va_start(ap, fmt);
SDL_vsnprintf(error->str, ERR_MAX_STRLEN, fmt, ap);
va_end(ap);
if (SDL_LogGetPriority(SDL_LOG_CATEGORY_ERROR) <= SDL_LOG_PRIORITY_DEBUG) {
/* If we are in debug mode, print out the error message */
SDL_LogDebug(SDL_LOG_CATEGORY_ERROR, "%s", error->str);
}
}
return -1;
}
/* Available for backwards compatibility */
const char *
SDL_GetError(void)
{
const SDL_error *error = SDL_GetErrBuf();
return error->error ? error->str : "";
}
void
SDL_ClearError(void)
{
SDL_GetErrBuf()->error = 0;
}
/* Very common errors go here */
int
SDL_Error(SDL_errorcode code)
{
switch (code) {
case SDL_ENOMEM:
return SDL_SetError("Out of memory");
case SDL_EFREAD:
return SDL_SetError("Error reading from datastream");
case SDL_EFWRITE:
return SDL_SetError("Error writing to datastream");
case SDL_EFSEEK:
return SDL_SetError("Error seeking in datastream");
case SDL_UNSUPPORTED:
return SDL_SetError("That operation is not supported");
default:
return SDL_SetError("Unknown SDL error");
}
}
#ifdef TEST_ERROR
int
main(int argc, char *argv[])
{
char buffer[BUFSIZ + 1];
SDL_SetError("Hi there!");
printf("Error 1: %s\n", SDL_GetError());
SDL_ClearError();
SDL_memset(buffer, '1', BUFSIZ);
buffer[BUFSIZ] = 0;
SDL_SetError("This is the error: %s (%f)", buffer, 1.0);
printf("Error 2: %s\n", SDL_GetError());
exit(0);
}
#endif
char *
SDL_GetErrorMsg(char *errstr, int maxlen)
{
const SDL_error *error = SDL_GetErrBuf();
if (error->error) {
SDL_strlcpy(errstr, error->str, maxlen);
} else {
*errstr = '\0';
}
return errstr;
}
/* vi: set ts=4 sw=4 expandtab: */