Mercurial > sdl-ios-xcode
view src/thread/beos/SDL_systhread.c @ 1544:ab1e4c41ab71
Fixed bug #33
Mike Frysinger wrote:
> with libsdl-1.2.9, some games (like bomberclone) started
> segfaulting in Gentoo
[...snip...]
> the last change in the last hunk:
[...snip...]
> if i change the statement to read:
> (table[which].blit_features & GetBlitFeatures()) == GetBlitFeatures()
> bomberclone no longer segfaults on my box
Alex Volkov wrote:
> The test "(table[which].blit_features & GetBlitFeatures()) ==
> table[which].blit_features)" is correct, and the previous
> "(table[which].cpu_mmx == SDL_HasMMX())" was actually broken.
I think there is potentially a slightly different cause of the above problem.
During the introduction of the Altivec code, the blit_table struct field
'alpha' got changed from a straightforward enum to a bitmask, which makes
perfect sense by itself. However, now the table driven blitter selection code
in SDL_CalculateBlitN() can choose the wrong blitters when searching for a
NO_ALPHA blitter because of the following code:
int a_need = 0;
...
(a_need & table[which].alpha) == a_need &&
When searching through the normal_blit_2[] table, a SET_ALPHA blitter (like
Blit_RGB565_ARGB8888) can now be selected instead of a NO_ALPHA one, causing
alpha channel bits to appear in a non-alpha destination surface. I suppose this
could theoretically be an indirect cause of the segfault mentioned above.
I *think* this can be fixed by changing to
int a_need = NO_ALPHA;
author | Sam Lantinga <slouken@libsdl.org> |
---|---|
date | Wed, 15 Mar 2006 15:47:49 +0000 |
parents | d910939febfa |
children | 782fd950bd46 c121d94672cb a1b03ba2fcd0 |
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/* SDL - Simple DirectMedia Layer Copyright (C) 1997-2006 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" /* BeOS thread management routines for SDL */ #include <stdio.h> #include <signal.h> #include <be/kernel/OS.h> #include "SDL_mutex.h" #include "SDL_thread.h" #include "../SDL_thread_c.h" #include "../SDL_systhread.h" static int sig_list[] = { SIGHUP, SIGINT, SIGQUIT, SIGPIPE, SIGALRM, SIGTERM, SIGWINCH, 0 }; void SDL_MaskSignals(sigset_t *omask) { sigset_t mask; int i; sigemptyset(&mask); for ( i=0; sig_list[i]; ++i ) { sigaddset(&mask, sig_list[i]); } sigprocmask(SIG_BLOCK, &mask, omask); } void SDL_UnmaskSignals(sigset_t *omask) { sigprocmask(SIG_SETMASK, omask, NULL); } static int32 RunThread(void *data) { SDL_RunThread(data); return(0); } int SDL_SYS_CreateThread(SDL_Thread *thread, void *args) { /* Create the thread and go! */ thread->handle=spawn_thread(RunThread, "SDL", B_NORMAL_PRIORITY, args); if ( (thread->handle == B_NO_MORE_THREADS) || (thread->handle == B_NO_MEMORY) ) { SDL_SetError("Not enough resources to create thread"); return(-1); } resume_thread(thread->handle); return(0); } void SDL_SYS_SetupThread(void) { /* Mask asynchronous signals for this thread */ SDL_MaskSignals(NULL); } Uint32 SDL_ThreadID(void) { return((Uint32)find_thread(NULL)); } void SDL_SYS_WaitThread(SDL_Thread *thread) { status_t the_status; wait_for_thread(thread->handle, &the_status); } void SDL_SYS_KillThread(SDL_Thread *thread) { kill_thread(thread->handle); }