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/* |
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* video_vosf.h - Video/graphics emulation, video on SEGV signals support |
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* |
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* Basilisk II (C) 1997-2000 Christian Bauer |
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* |
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* This program is free software; you can redistribute it and/or modify |
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* it under the terms of the GNU General Public License as published by |
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* the Free Software Foundation; either version 2 of the License, or |
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* (at your option) any later version. |
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* |
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* This program is distributed in the hope that it will be useful, |
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* but WITHOUT ANY WARRANTY; without even the implied warranty of |
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
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* GNU General Public License for more details. |
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* |
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* You should have received a copy of the GNU General Public License |
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* along with this program; if not, write to the Free Software |
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* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
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*/ |
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|
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#ifndef VIDEO_VOSF_H |
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#define VIDEO_VOSF_H |
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|
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// Note: this file is #include'd in video_x.cpp |
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#ifdef ENABLE_VOSF |
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|
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/* |
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* Page-aligned memory allocation |
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*/ |
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|
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// Align on page boundaries |
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static uintptr align_on_page_boundary(uintptr size) |
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{ |
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const uint32 page_size = getpagesize(); |
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const uint32 page_mask = page_size - 1; |
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return (size + page_mask) & ~page_mask; |
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} |
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|
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// Allocate memory on page boundary |
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static void * allocate_framebuffer(uint32 size, uint8 * hint = 0) |
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{ |
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// Remind that the system can allocate at 0x00000000... |
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return mmap((caddr_t)hint, size, PROT_READ | PROT_WRITE, MAP_PRIVATE, zero_fd, 0); |
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} |
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|
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|
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/* |
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* Screen depth identification |
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*/ |
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|
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enum { |
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ID_DEPTH_UNKNOWN = -1, |
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ID_DEPTH_1, |
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ID_DEPTH_8, |
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ID_DEPTH_15, |
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ID_DEPTH_16, |
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ID_DEPTH_24, |
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ID_DEPTH_32 = ID_DEPTH_24, |
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ID_DEPTH_COUNT |
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}; |
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|
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static int depth_id(int depth) |
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{ |
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int id; |
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switch (depth) { |
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case 1 : id = ID_DEPTH_1; break; |
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case 8 : id = ID_DEPTH_8; break; |
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case 15 : id = ID_DEPTH_15; break; |
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case 16 : id = ID_DEPTH_16; break; |
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case 24 : id = ID_DEPTH_24; break; |
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case 32 : id = ID_DEPTH_32; break; |
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default : id = ID_DEPTH_UNKNOWN; |
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} |
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return id; |
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} |
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|
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|
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/* |
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* Frame buffer copy function templates |
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*/ |
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|
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// No conversion required |
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|
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#define MEMCPY_PROFITABLE |
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#ifdef MEMCPY_PROFITABLE |
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static void do_fbcopy_raw(uint8 * dest, const uint8 * source, uint32 length) |
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{ |
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memcpy(dest, source, length); |
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} |
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#else |
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#define FB_BLIT_1(dst, src) (dst = (src)) |
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#define FB_BLIT_2(dst, src) (dst = (src)) |
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#define FB_DEPTH 0 |
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#define FB_FUNC_NAME do_fbcopy_raw |
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#include "video_blit.h" |
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#endif |
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|
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|
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// RGB 555 |
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|
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#ifdef WORDS_BIGENDIAN |
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# define FB_FUNC_NAME do_fbcopy_15_obo |
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#else |
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# define FB_FUNC_NAME do_fbcopy_15_nbo |
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#endif |
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|
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#define FB_BLIT_1(dst, src) \ |
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(dst = (((src) >> 8) & 0xff) | (((src) & 0xff) << 8)) |
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|
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#define FB_BLIT_2(dst, src) \ |
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(dst = (((src) >> 8) & 0x00ff00ff) | (((src) & 0x00ff00ff) << 8)) |
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|
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#define FB_DEPTH 15 |
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#include "video_blit.h" |
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|
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|
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// RGB 565 |
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|
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#ifdef WORDS_BIGENDIAN |
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|
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// native byte order |
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|
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#define FB_BLIT_1(dst, src) \ |
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(dst = (((src) & 0x1f) | (((src) << 1) & 0xffc0))) |
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|
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#define FB_BLIT_2(dst, src) \ |
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(dst = (((src) & 0x001f001f) | (((src) << 1) & 0xffc0ffc0))) |
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|
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#define FB_DEPTH 16 |
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#define FB_FUNC_NAME do_fbcopy_16_nbo |
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#include "video_blit.h" |
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|
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// opposite byte order |
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|
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#define FB_BLIT_1(dst, src) \ |
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(dst = ((((src) >> 7) & 0xff) | (((src) << 9) & 0xc000) | (((src) << 8) & 0x1f00))) |
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|
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#define FB_BLIT_2(dst, src) \ |
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(dst = ((((src) >> 7) & 0x00ff00ff) | (((src) << 9) & 0xc000c000) | (((src) << 8) & 0x1f001f00))) |
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|
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#define FB_DEPTH 16 |
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#define FB_FUNC_NAME do_fbcopy_16_obo |
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#include "video_blit.h" |
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|
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#else |
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|
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// native byte order |
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|
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#define FB_BLIT_1(dst, src) \ |
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(dst = (((src) >> 8) & 0x001f) | (((src) << 9) & 0xfe00) | (((src) >> 7) & 0x01c0)) |
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|
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#define FB_BLIT_2(dst, src) \ |
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(dst = (((src) >> 8) & 0x001f001f) | (((src) << 9) & 0xfe00fe00) | (((src) >> 7) & 0x01c001c0)) |
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|
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#define FB_DEPTH 16 |
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#define FB_FUNC_NAME do_fbcopy_16_nbo |
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#include "video_blit.h" |
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|
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// opposite byte order (untested) |
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|
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#define FB_BLIT_1(dst, src) \ |
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(dst = (((src) & 0x1f00) | (((src) << 1) & 0xe0fe) | (((src) >> 15) & 1))) |
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|
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#define FB_BLIT_2(dst, src) \ |
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(dst = (((src) & 0x1f001f00) | (((src) << 1) & 0xe0fee0fe) | (((src) >> 15) & 0x10001))) |
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|
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#define FB_DEPTH 16 |
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#define FB_FUNC_NAME do_fbcopy_16_obo |
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#include "video_blit.h" |
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|
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#endif |
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|
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// RGB 888 |
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|
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#ifdef WORDS_BIGENDIAN |
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# define FB_FUNC_NAME do_fbcopy_24_obo |
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#else |
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# define FB_FUNC_NAME do_fbcopy_24_nbo |
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#endif |
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|
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#define FB_BLIT_1(dst, src) \ |
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(dst = (src)) |
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|
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#define FB_BLIT_2(dst, src) \ |
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(dst = (((src) >> 24) & 0xff) | (((src) >> 8) & 0xff00) | (((src) & 0xff00) << 8) | (((src) & 0xff) << 24)) |
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|
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#define FB_DEPTH 24 |
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#include "video_blit.h" |
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|
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|
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/* |
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* Frame buffer copy functions map table |
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*/ |
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|
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typedef void (*fbcopy_func)(uint8 *, const uint8 *, uint32); |
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static fbcopy_func do_update_framebuffer; |
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|
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#define FBCOPY_FUNC(aHandler) do_ ## aHandler |
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|
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#if REAL_ADDRESSING || DIRECT_ADDRESSING |
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#define WD(X) { FBCOPY_FUNC(X), FBCOPY_FUNC(X) } |
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#else |
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#define WD(X) { FBCOPY_FUNC(fbcopy_raw), FBCOPY_FUNC(fbcopy_raw) } |
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#endif |
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|
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// fb_copy_funcs[depth_id][native_byte_order][dga_mode] |
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// NT : not tested |
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// OK : has been successfully tested |
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// NBO : native byte order (X server vs. client) |
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// OBO : opposite byte order (X server vs. client) |
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static fbcopy_func fbcopy_funcs[ID_DEPTH_COUNT][2][2] = { |
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#ifdef WORDS_BIGENDIAN |
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/* opposite byte order native byte order */ |
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/* 1 bpp */ { WD(fbcopy_raw) , WD(fbcopy_raw) }, // NT |
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/* 8 bpp */ { WD(fbcopy_raw) , WD(fbcopy_raw) }, // OK (NBO) |
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/* 15 bpp */ { WD(fbcopy_15_obo) , WD(fbcopy_raw) }, // OK (OBO) |
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/* 16 bpp */ { WD(fbcopy_16_obo) , WD(fbcopy_16_nbo) }, // OK (OBO) |
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/* 24 bpp */ { WD(fbcopy_24_obo) , WD(fbcopy_raw) } // OK (OBO) |
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#else |
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/* opposite byte order native byte order */ |
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/* 1 bpp */ { WD(fbcopy_raw) , WD(fbcopy_raw) }, // NT |
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/* 8 bpp */ { WD(fbcopy_raw) , WD(fbcopy_raw) }, // OK (NBO) |
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/* 15 bpp */ { WD(fbcopy_raw) , WD(fbcopy_15_nbo) }, // OK (NBO) |
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/* 16 bpp */ { WD(fbcopy_16_obo) , WD(fbcopy_16_nbo) }, // OK (NBO) |
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/* 24 bpp */ { WD(fbcopy_raw) , WD(fbcopy_24_nbo) } // OK (NBO) |
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#endif |
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}; |
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|
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#undef WD |
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|
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#define FBCOPY_FUNC_ERROR \ |
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ErrorAlert("Invalid screen depth") |
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|
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#define GET_FBCOPY_FUNC(aDepth, aNativeByteOrder, aDisplay) \ |
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((depth_id(aDepth) == ID_DEPTH_UNKNOWN) ? ( FBCOPY_FUNC_ERROR, (fbcopy_func)0 ) : \ |
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fbcopy_funcs[depth_id(aDepth)][(aNativeByteOrder)][(aDisplay) == DISPLAY_DGA ? 1 : 0]) |
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|
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|
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/* |
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* Screen fault handler |
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*/ |
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|
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const uintptr INVALID_PC = (uintptr)-1; |
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|
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static inline void do_handle_screen_fault(uintptr addr, uintptr pc = INVALID_PC) |
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{ |
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/* Someone attempted to write to the frame buffer. Make it writeable |
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* now so that the data could actually be written. It will be made |
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* read-only back in one of the screen update_*() functions. |
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*/ |
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if ((addr >= mainBuffer.memStart) && (addr < mainBuffer.memEnd)) { |
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const int page = (addr - mainBuffer.memStart) >> mainBuffer.pageBits; |
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caddr_t page_ad = (caddr_t)(addr & ~(mainBuffer.pageSize - 1)); |
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LOCK_VOSF; |
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PFLAG_SET(page); |
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mprotect(page_ad, mainBuffer.pageSize, PROT_READ | PROT_WRITE); |
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UNLOCK_VOSF; |
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return; |
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} |
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|
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/* Otherwise, we don't know how to handle the fault, let it crash */ |
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fprintf(stderr, "do_handle_screen_fault: unhandled address 0x%08X", addr); |
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if (pc != INVALID_PC) |
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fprintf(stderr, " [IP=0x%08X]", pc); |
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fprintf(stderr, "\n"); |
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|
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signal(SIGSEGV, SIG_DFL); |
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} |
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|
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#if defined(HAVE_SIGINFO_T) |
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|
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static void Screen_fault_handler(int, siginfo_t * sip, void *) |
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{ |
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D(bug("Screen_fault_handler: ADDR=0x%08X\n", sip->si_addr)); |
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do_handle_screen_fault((uintptr)sip->si_addr); |
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} |
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|
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#elif defined(HAVE_SIGCONTEXT_SUBTERFUGE) |
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|
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# if defined(__i386__) && defined(__linux__) |
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static void Screen_fault_handler(int, struct sigcontext scs) |
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{ |
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D(bug("Screen_fault_handler: ADDR=0x%08X from IP=0x%08X\n", scs.cr2, scs.eip)); |
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do_handle_screen_fault((uintptr)scs.cr2, (uintptr)scs.eip); |
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} |
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|
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# elif defined(__m68k__) && defined(__NetBSD__) |
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|
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# include <m68k/frame.h> |
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static void Screen_fault_handler(int, int code, struct sigcontext *scp) |
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{ |
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D(bug("Screen_fault_handler: ADDR=0x%08X\n", code)); |
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struct sigstate { |
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int ss_flags; |
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struct frame ss_frame; |
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}; |
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struct sigstate *state = (struct sigstate *)scp->sc_ap; |
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uintptr fault_addr; |
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switch (state->ss_frame.f_format) { |
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case 7: // 68040 access error |
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// "code" is sometimes unreliable (i.e. contains NULL or a bogus address), reason unknown |
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fault_addr = state->ss_frame.f_fmt7.f_fa; |
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break; |
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default: |
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fault_addr = (uintptr)code; |
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break; |
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} |
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do_handle_screen_fault(fault_addr); |
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} |
310 |
|
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# else |
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# error "No suitable subterfuge for Video on SEGV signals" |
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# endif |
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#else |
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# error "Can't do Video on SEGV signals" |
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#endif |
317 |
|
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|
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/* |
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* Screen fault handler initialization |
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*/ |
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|
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#if defined(HAVE_SIGINFO_T) |
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static bool Screen_fault_handler_init() |
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{ |
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// Setup SIGSEGV handler to process writes to frame buffer |
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sigemptyset(&vosf_sa.sa_mask); |
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vosf_sa.sa_sigaction = Screen_fault_handler; |
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vosf_sa.sa_flags = SA_SIGINFO; |
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return (sigaction(SIGSEGV, &vosf_sa, NULL) == 0); |
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} |
332 |
#elif defined(HAVE_SIGCONTEXT_SUBTERFUGE) |
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static bool Screen_fault_handler_init() |
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{ |
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// Setup SIGSEGV handler to process writes to frame buffer |
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sigemptyset(&vosf_sa.sa_mask); |
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vosf_sa.sa_handler = (void (*)(int)) Screen_fault_handler; |
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#if !EMULATED_68K && defined(__NetBSD__) |
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sigaddset(&vosf_sa.sa_mask, SIGALRM); |
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vosf_sa.sa_flags = SA_ONSTACK; |
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#else |
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vosf_sa.sa_flags = 0; |
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#endif |
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return (sigaction(SIGSEGV, &vosf_sa, NULL) == 0); |
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} |
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#endif |
347 |
|
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|
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/* |
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* Update display for Windowed mode and VOSF |
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*/ |
352 |
|
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/* How can we deal with array overrun conditions ? |
354 |
|
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The state of the framebuffer pages that have been touched are maintained |
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in the dirtyPages[] table. That table is (pageCount + 2) bytes long. |
357 |
|
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Terminology |
359 |
|
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"Last Page" denotes the pageCount-nth page, i.e. dirtyPages[pageCount - 1]. |
361 |
"CLEAR Page Guard" refers to the page following the Last Page but is always |
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in the CLEAR state. "SET Page Guard" refers to the page following the CLEAR |
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Page Guard but is always in the SET state. |
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|
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Rough process |
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|
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The update routines must determine which pages have to blitted to the |
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screen. This job consists in finding the first_page that was touched. |
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i.e. find the next page that is SET. Then, finding how many pages were |
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touched starting from first_page. i.e. find the next page that is CLEAR. |
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|
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Two cases |
373 |
|
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- Last Page is CLEAR: find_next_page_set() will reach the SET Page Guard |
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but it is beyond the valid pageCount value. Therefore, we exit from the |
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update routine. |
377 |
|
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- Last Page is SET: first_page equals (pageCount - 1) and |
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find_next_page_clear() will reach the CLEAR Page Guard. We blit the last |
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page to the screen. On the next iteration, page equals pageCount and |
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find_next_page_set() will reach the SET Page Guard. We still safely exit |
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from the update routine because the SET Page Guard position is greater |
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than pageCount. |
384 |
*/ |
385 |
|
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static inline void update_display_window_vosf(void) |
387 |
{ |
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int page = 0; |
389 |
for (;;) { |
390 |
const int first_page = find_next_page_set(page); |
391 |
if (first_page >= mainBuffer.pageCount) |
392 |
break; |
393 |
|
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page = find_next_page_clear(first_page); |
395 |
PFLAG_CLEAR_RANGE(first_page, page); |
396 |
|
397 |
// Make the dirty pages read-only again |
398 |
const int32 offset = first_page << mainBuffer.pageBits; |
399 |
const uint32 length = (page - first_page) << mainBuffer.pageBits; |
400 |
mprotect((caddr_t)(mainBuffer.memStart + offset), length, PROT_READ); |
401 |
|
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// There is at least one line to update |
403 |
const int y1 = mainBuffer.pageInfo[first_page].top; |
404 |
const int y2 = mainBuffer.pageInfo[page - 1].bottom; |
405 |
const int height = y2 - y1 + 1; |
406 |
|
407 |
const int bytes_per_row = VideoMonitor.bytes_per_row; |
408 |
const int bytes_per_pixel = VideoMonitor.bytes_per_row / VideoMonitor.x; |
409 |
int i, j; |
410 |
|
411 |
// Check for first column from left and first column |
412 |
// from right that have changed |
413 |
int x1, x2, width; |
414 |
if (depth == 1) { |
415 |
|
416 |
x1 = VideoMonitor.x - 1; |
417 |
for (j = y1; j <= y2; j++) { |
418 |
uint8 * const p1 = &the_buffer[j * bytes_per_row]; |
419 |
uint8 * const p2 = &the_buffer_copy[j * bytes_per_row]; |
420 |
for (i = 0; i < (x1>>3); i++) { |
421 |
if (p1[i] != p2[i]) { |
422 |
x1 = i << 3; |
423 |
break; |
424 |
} |
425 |
} |
426 |
} |
427 |
|
428 |
x2 = x1; |
429 |
for (j = y2; j >= y1; j--) { |
430 |
uint8 * const p1 = &the_buffer[j * bytes_per_row]; |
431 |
uint8 * const p2 = &the_buffer_copy[j * bytes_per_row]; |
432 |
for (i = (VideoMonitor.x>>3) - 1; i > (x2>>3); i--) { |
433 |
if (p1[i] != p2[i]) { |
434 |
x2 = (i << 3) + 7; |
435 |
break; |
436 |
} |
437 |
} |
438 |
} |
439 |
width = x2 - x1 + 1; |
440 |
|
441 |
// Update the_host_buffer and copy of the_buffer |
442 |
i = y1 * bytes_per_row + (x1 >> 3); |
443 |
for (j = y1; j <= y2; j++) { |
444 |
do_update_framebuffer(the_host_buffer + i, the_buffer + i, width >> 3); |
445 |
memcpy(the_buffer_copy + i, the_buffer + i, width >> 3); |
446 |
i += bytes_per_row; |
447 |
} |
448 |
|
449 |
} else { |
450 |
|
451 |
x1 = VideoMonitor.x * bytes_per_pixel - 1; |
452 |
for (j = y1; j <= y2; j++) { |
453 |
uint8 * const p1 = &the_buffer[j * bytes_per_row]; |
454 |
uint8 * const p2 = &the_buffer_copy[j * bytes_per_row]; |
455 |
for (i = 0; i < x1; i++) { |
456 |
if (p1[i] != p2[i]) { |
457 |
x1 = i; |
458 |
break; |
459 |
} |
460 |
} |
461 |
} |
462 |
x1 /= bytes_per_pixel; |
463 |
|
464 |
x2 = x1 * bytes_per_pixel; |
465 |
for (j = y2; j >= y1; j--) { |
466 |
uint8 * const p1 = &the_buffer[j * bytes_per_row]; |
467 |
uint8 * const p2 = &the_buffer_copy[j * bytes_per_row]; |
468 |
for (i = VideoMonitor.x * bytes_per_pixel - 1; i > x2; i--) { |
469 |
if (p1[i] != p2[i]) { |
470 |
x2 = i; |
471 |
break; |
472 |
} |
473 |
} |
474 |
} |
475 |
x2 /= bytes_per_pixel; |
476 |
width = x2 - x1 + 1; |
477 |
|
478 |
// Update the_host_buffer and copy of the_buffer |
479 |
i = y1 * bytes_per_row + x1 * bytes_per_pixel; |
480 |
for (j = y1; j <= y2; j++) { |
481 |
do_update_framebuffer(the_host_buffer + i, the_buffer + i, bytes_per_pixel * width); |
482 |
memcpy(the_buffer_copy + i, the_buffer + i, bytes_per_pixel * width); |
483 |
i += bytes_per_row; |
484 |
} |
485 |
} |
486 |
|
487 |
if (have_shm) |
488 |
XShmPutImage(x_display, the_win, the_gc, img, x1, y1, x1, y1, width, height, 0); |
489 |
else |
490 |
XPutImage(x_display, the_win, the_gc, img, x1, y1, x1, y1, width, height); |
491 |
} |
492 |
} |
493 |
|
494 |
|
495 |
/* |
496 |
* Update display for DGA mode and VOSF |
497 |
* (only in Direct Addressing mode) |
498 |
*/ |
499 |
|
500 |
#if REAL_ADDRESSING || DIRECT_ADDRESSING |
501 |
static inline void update_display_dga_vosf(void) |
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{ |
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int page = 0; |
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for (;;) { |
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const int first_page = find_next_page_set(page); |
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if (first_page >= mainBuffer.pageCount) |
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break; |
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|
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page = find_next_page_clear(first_page); |
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PFLAG_CLEAR_RANGE(first_page, page); |
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|
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// Make the dirty pages read-only again |
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const int32 offset = first_page << mainBuffer.pageBits; |
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const uint32 length = (page - first_page) << mainBuffer.pageBits; |
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mprotect((caddr_t)(mainBuffer.memStart + offset), length, PROT_READ); |
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|
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// I am sure that y2 >= y1 and depth != 1 |
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const int y1 = mainBuffer.pageInfo[first_page].top; |
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const int y2 = mainBuffer.pageInfo[page - 1].bottom; |
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|
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const int bytes_per_row = VideoMonitor.bytes_per_row; |
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const int bytes_per_pixel = VideoMonitor.bytes_per_row / VideoMonitor.x; |
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int i, j; |
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|
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// Check for first column from left and first column |
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// from right that have changed |
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int x1 = VideoMonitor.x * bytes_per_pixel - 1; |
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for (j = y1; j <= y2; j++) { |
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uint8 * const p1 = &the_buffer[j * bytes_per_row]; |
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uint8 * const p2 = &the_buffer_copy[j * bytes_per_row]; |
531 |
for (i = 0; i < x1; i++) { |
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if (p1[i] != p2[i]) { |
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x1 = i; |
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break; |
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} |
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} |
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} |
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x1 /= bytes_per_pixel; |
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|
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int x2 = x1 * bytes_per_pixel; |
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for (j = y2; j >= y1; j--) { |
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uint8 * const p1 = &the_buffer[j * bytes_per_row]; |
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uint8 * const p2 = &the_buffer_copy[j * bytes_per_row]; |
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for (i = VideoMonitor.x * bytes_per_pixel - 1; i > x2; i--) { |
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if (p1[i] != p2[i]) { |
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x2 = i; |
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break; |
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} |
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} |
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} |
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x2 /= bytes_per_pixel; |
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|
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// Update the_host_buffer and copy of the_buffer |
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// There should be at least one pixel to copy |
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const int width = x2 - x1 + 1; |
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i = y1 * bytes_per_row + x1 * bytes_per_pixel; |
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for (j = y1; j <= y2; j++) { |
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do_update_framebuffer(the_host_buffer + i, the_buffer + i, bytes_per_pixel * width); |
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memcpy(the_buffer_copy + i, the_buffer + i, bytes_per_pixel * width); |
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i += bytes_per_row; |
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} |
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} |
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} |
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#endif |
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|
566 |
#endif /* ENABLE_VOSF */ |
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|
568 |
#endif /* VIDEO_VOSF_H */ |