Mercurial > sdl-ios-xcode
annotate include/SDL_rwops.h @ 968:4675910b0b7b
Date: Mon, 11 Oct 2004 15:17:27 +0300 (EEST)
From: Hannu Savolainen
Subject: Re: SDL uses obsolete OSS features
I did some work on getting OSS to work better with SDL. There have been
some problems with select which should be fixed now.
I'm having some problems in understanding what is the purpose of the
DSP_WaitAudio() routine. I added a return to the very beginning of this
routine and commendted out the define for USE_BLOCKING_WRITES. At least
lbreakout2 seems to work as well as earlier. The latencies are the same.
An ordinary blocking write does exactly the same thing than DSP_WaitAudio
does. So I would recommend using the USE_BLOCKING_WRITES approach and
removing everything from the DSP_WaitAudio routine. Also enabling
USE_BLOCKING_WRITES makes it possible to simplify DSP_PlayAudio() because
you don't need to handle the partial writes (the do-while loop).
Attached is a patch against SDL-1.2.7. After these changes SDL will use
OSS as it's designed to be used (make it as simple as possible). This code
should work with all OSS implementations because it uses only the very
fundamental features that have been there since the jurassic times.
| author | Sam Lantinga <slouken@libsdl.org> |
|---|---|
| date | Fri, 12 Nov 2004 21:39:04 +0000 |
| parents | 02759105b989 |
| children | c9b51268668f |
| rev | line source |
|---|---|
| 0 | 1 /* |
| 2 SDL - Simple DirectMedia Layer | |
|
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Updated copyright information for 2004 (Happy New Year!)
Sam Lantinga <slouken@libsdl.org>
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3 Copyright (C) 1997-2004 Sam Lantinga |
| 0 | 4 |
| 5 This library is free software; you can redistribute it and/or | |
| 6 modify it under the terms of the GNU Library General Public | |
| 7 License as published by the Free Software Foundation; either | |
| 8 version 2 of the License, or (at your option) any later version. | |
| 9 | |
| 10 This library is distributed in the hope that it will be useful, | |
| 11 but WITHOUT ANY WARRANTY; without even the implied warranty of | |
| 12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
| 13 Library General Public License for more details. | |
| 14 | |
| 15 You should have received a copy of the GNU Library General Public | |
| 16 License along with this library; if not, write to the Free | |
| 17 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA | |
| 18 | |
| 19 Sam Lantinga | |
|
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Updated the headers with the correct e-mail address
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20 slouken@libsdl.org |
| 0 | 21 */ |
| 22 | |
| 23 #ifdef SAVE_RCSID | |
| 24 static char rcsid = | |
| 25 "@(#) $Id$"; | |
| 26 #endif | |
| 27 | |
| 28 /* This file provides a general interface for SDL to read and write | |
| 29 data sources. It can easily be extended to files, memory, etc. | |
| 30 */ | |
| 31 | |
| 32 #ifndef _SDL_RWops_h | |
| 33 #define _SDL_RWops_h | |
| 34 | |
| 35 #include <stdio.h> | |
| 36 | |
| 37 #include "SDL_types.h" | |
| 38 | |
| 39 #include "begin_code.h" | |
| 40 /* Set up for C function definitions, even when using C++ */ | |
| 41 #ifdef __cplusplus | |
| 42 extern "C" { | |
| 43 #endif | |
| 44 | |
| 45 /* This is the read/write operation structure -- very basic */ | |
| 46 | |
| 47 typedef struct SDL_RWops { | |
| 48 /* Seek to 'offset' relative to whence, one of stdio's whence values: | |
| 49 SEEK_SET, SEEK_CUR, SEEK_END | |
| 50 Returns the final offset in the data source. | |
| 51 */ | |
|
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02759105b989
Date: Fri, 20 Aug 2004 08:31:20 +0200
Sam Lantinga <slouken@libsdl.org>
parents:
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diff
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52 int (SDLCALL *seek)(struct SDL_RWops *context, int offset, int whence); |
| 0 | 53 |
| 54 /* Read up to 'num' objects each of size 'objsize' from the data | |
| 55 source to the area pointed at by 'ptr'. | |
| 56 Returns the number of objects read, or -1 if the read failed. | |
| 57 */ | |
|
930
02759105b989
Date: Fri, 20 Aug 2004 08:31:20 +0200
Sam Lantinga <slouken@libsdl.org>
parents:
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58 int (SDLCALL *read)(struct SDL_RWops *context, void *ptr, int size, int maxnum); |
| 0 | 59 |
| 60 /* Write exactly 'num' objects each of size 'objsize' from the area | |
| 61 pointed at by 'ptr' to data source. | |
| 62 Returns 'num', or -1 if the write failed. | |
| 63 */ | |
|
930
02759105b989
Date: Fri, 20 Aug 2004 08:31:20 +0200
Sam Lantinga <slouken@libsdl.org>
parents:
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diff
changeset
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64 int (SDLCALL *write)(struct SDL_RWops *context, const void *ptr, int size, int num); |
| 0 | 65 |
| 66 /* Close and free an allocated SDL_FSops structure */ | |
|
930
02759105b989
Date: Fri, 20 Aug 2004 08:31:20 +0200
Sam Lantinga <slouken@libsdl.org>
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67 int (SDLCALL *close)(struct SDL_RWops *context); |
| 0 | 68 |
| 69 Uint32 type; | |
| 70 union { | |
| 71 struct { | |
| 72 int autoclose; | |
| 73 FILE *fp; | |
| 74 } stdio; | |
| 75 struct { | |
| 76 Uint8 *base; | |
| 77 Uint8 *here; | |
| 78 Uint8 *stop; | |
| 79 } mem; | |
| 80 struct { | |
| 81 void *data1; | |
| 82 } unknown; | |
| 83 } hidden; | |
| 84 | |
| 85 } SDL_RWops; | |
| 86 | |
| 87 | |
| 88 /* Functions to create SDL_RWops structures from various data sources */ | |
| 89 | |
|
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Explicitly specify the SDL API calling convention (C by default)
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90 extern DECLSPEC SDL_RWops * SDLCALL SDL_RWFromFile(const char *file, const char *mode); |
| 0 | 91 |
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Explicitly specify the SDL API calling convention (C by default)
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92 extern DECLSPEC SDL_RWops * SDLCALL SDL_RWFromFP(FILE *fp, int autoclose); |
| 0 | 93 |
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Explicitly specify the SDL API calling convention (C by default)
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94 extern DECLSPEC SDL_RWops * SDLCALL SDL_RWFromMem(void *mem, int size); |
|
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Added function to create RWops from const memory: SDL_RWFromConstMem()
Sam Lantinga <slouken@libsdl.org>
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95 extern DECLSPEC SDL_RWops * SDLCALL SDL_RWFromConstMem(const void *mem, int size); |
| 0 | 96 |
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Explicitly specify the SDL API calling convention (C by default)
Sam Lantinga <slouken@libsdl.org>
parents:
297
diff
changeset
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97 extern DECLSPEC SDL_RWops * SDLCALL SDL_AllocRW(void); |
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9154ec9ca3d2
Explicitly specify the SDL API calling convention (C by default)
Sam Lantinga <slouken@libsdl.org>
parents:
297
diff
changeset
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98 extern DECLSPEC void SDLCALL SDL_FreeRW(SDL_RWops *area); |
| 0 | 99 |
| 100 /* Macros to easily read and write from an SDL_RWops structure */ | |
| 101 #define SDL_RWseek(ctx, offset, whence) (ctx)->seek(ctx, offset, whence) | |
| 102 #define SDL_RWtell(ctx) (ctx)->seek(ctx, 0, SEEK_CUR) | |
| 103 #define SDL_RWread(ctx, ptr, size, n) (ctx)->read(ctx, ptr, size, n) | |
| 104 #define SDL_RWwrite(ctx, ptr, size, n) (ctx)->write(ctx, ptr, size, n) | |
| 105 #define SDL_RWclose(ctx) (ctx)->close(ctx) | |
| 106 | |
| 107 | |
| 108 /* Ends C function definitions when using C++ */ | |
| 109 #ifdef __cplusplus | |
| 110 } | |
| 111 #endif | |
| 112 #include "close_code.h" | |
| 113 | |
| 114 #endif /* _SDL_RWops_h */ |