author Sam Lantinga <slouken@libsdl.org>
Sun, 07 Jul 2019 09:10:56 -0700
changeset 12928 3c4a4b1077cd
parent 12503 806492103856
permissions -rw-r--r--
Fixed bug 4710 - audio/alsa: avoid configuring hardware parameters with only a single period

Anthony Pesch

The previous code first configured the period size using snd_pcm_hw_par-
ams_set_period_size_near. Then, it further narrowed the configuration
space by calling snd_pcm_hw_params_set_buffer_size_near using a buffer
size of 2 times the _requested_ period size in order to try and get a
configuration with only 2 periods. If the configured period size was
larger than the requested size, the second call could inadvertently
narrow the configuration space to contain only a single period.

Rather than fixing the call to snd_pcm_hw_params_set_buffer_size_near
to use a size of 2 times the configured period size, the code has been
changed to use snd_pcm_hw_params_set_periods_min in order to more
clearly explain the intent.
     1 /*
     2   Copyright (C) 1997-2019 Sam Lantinga <slouken@libsdl.org>
     4   This software is provided 'as-is', without any express or implied
     5   warranty.  In no event will the authors be held liable for any damages
     6   arising from the use of this software.
     8   Permission is granted to anyone to use this software for any purpose,
     9   including commercial applications, and to alter it and redistribute it
    10   freely.
    11 */
    13 /* Definitions for platform dependent windowing functions to test SDL
    14    integration with native windows
    15 */
    17 #include "SDL.h"
    19 /* This header includes all the necessary system headers for native windows */
    20 #include "SDL_syswm.h"
    22 typedef struct
    23 {
    24     const char *tag;
    25     void *(*CreateNativeWindow) (int w, int h);
    26     void (*DestroyNativeWindow) (void *window);
    27 } NativeWindowFactory;
    30 #define TEST_NATIVE_WINDOWS
    31 extern NativeWindowFactory WindowsWindowFactory;
    32 #endif
    34 #ifdef SDL_VIDEO_DRIVER_X11
    35 #define TEST_NATIVE_X11
    36 extern NativeWindowFactory X11WindowFactory;
    37 #endif
    40 /* Actually, we don't really do this, since it involves adding Objective C
    41    support to the build system, which is a little tricky.  You can uncomment
    42    it manually though and link testnativecocoa.m into the test application.
    43 */
    44 #define TEST_NATIVE_COCOA
    45 extern NativeWindowFactory CocoaWindowFactory;
    46 #endif