Commit 8b22d943 authored by Takashi Iwai's avatar Takashi Iwai
Browse files

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: default avatarTakashi Iwai <tiwai@suse.de>
parent ded652f7

sound/core/pcm_lib.c

+5 −4
Original line number Diff line number Diff line
@@ -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;

	}