From 8b22d943c34b616eefbd6d2f8f197a53b1f29fd0 Mon Sep 17 00:00:00 2001 From: Takashi Iwai Date: Fri, 20 Mar 2009 16:26:15 +0100 Subject: [PATCH] ALSA: pcm - Safer boundary checks Make the boundary checks a bit safer. These caese are rare or theoretically won't happen, but nothing bad to keep the checks safer... Signed-off-by: Takashi Iwai --- sound/core/pcm_lib.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/sound/core/pcm_lib.c b/sound/core/pcm_lib.c index 063c675177a9..fbb2e391591e 100644 --- a/sound/core/pcm_lib.c +++ b/sound/core/pcm_lib.c @@ -222,8 +222,9 @@ static int snd_pcm_update_hw_ptr_interrupt(struct snd_pcm_substream *substream) hw_ptr_interrupt = runtime->hw_ptr_interrupt + runtime->period_size; delta = new_hw_ptr - hw_ptr_interrupt; if (hw_ptr_interrupt >= runtime->boundary) { - hw_ptr_interrupt %= runtime->boundary; - if (!hw_base) /* hw_base was already lapped; recalc delta */ + hw_ptr_interrupt -= runtime->boundary; + if (hw_base < runtime->boundary / 2) + /* hw_base was already lapped; recalc delta */ delta = new_hw_ptr - hw_ptr_interrupt; } if (delta < 0) { @@ -241,7 +242,7 @@ static int snd_pcm_update_hw_ptr_interrupt(struct snd_pcm_substream *substream) delta = 0; } else { hw_base += runtime->buffer_size; - if (hw_base == runtime->boundary) + if (hw_base >= runtime->boundary) hw_base = 0; new_hw_ptr = hw_base + pos; } @@ -296,7 +297,7 @@ int snd_pcm_update_hw_ptr(struct snd_pcm_substream *substream) return 0; } hw_base += runtime->buffer_size; - if (hw_base == runtime->boundary) + if (hw_base >= runtime->boundary) hw_base = 0; new_hw_ptr = hw_base + pos; }