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authorDavid S. Miller <davem@davemloft.net>2008-10-11 21:39:35 +0200
committerDavid S. Miller <davem@davemloft.net>2008-10-11 21:39:35 +0200
commit56c5d900dbb8e042bfad035d18433476931d8f93 (patch)
tree00b793965beeef10db03e0ff021d2d965c410759 /Documentation/sound/alsa/DocBook
parentleo: disable cursor when leaving graphics mode (diff)
parentMerge phase #4 (X2APIC, APIC unification, CPU identification unification) of ... (diff)
downloadlinux-56c5d900dbb8e042bfad035d18433476931d8f93.tar.xz
linux-56c5d900dbb8e042bfad035d18433476931d8f93.zip
Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/torvalds/linux-2.6
Conflicts: sound/core/memalloc.c
Diffstat (limited to 'Documentation/sound/alsa/DocBook')
-rw-r--r--Documentation/sound/alsa/DocBook/writing-an-alsa-driver.tmpl62
1 files changed, 38 insertions, 24 deletions
diff --git a/Documentation/sound/alsa/DocBook/writing-an-alsa-driver.tmpl b/Documentation/sound/alsa/DocBook/writing-an-alsa-driver.tmpl
index 56723b42813e..87a7c07ab658 100644
--- a/Documentation/sound/alsa/DocBook/writing-an-alsa-driver.tmpl
+++ b/Documentation/sound/alsa/DocBook/writing-an-alsa-driver.tmpl
@@ -6134,44 +6134,58 @@ struct _snd_pcm_runtime {
</para>
</section>
- <section id="useful-functions-snd-assert">
- <title><function>snd_assert()</function></title>
+ <section id="useful-functions-snd-bug">
+ <title><function>snd_BUG()</function></title>
<para>
- <function>snd_assert()</function> macro is similar with the
- normal <function>assert()</function> macro. For example,
+ It shows the <computeroutput>BUG?</computeroutput> message and
+ stack trace as well as <function>snd_BUG_ON</function> at the point.
+ It's useful to show that a fatal error happens there.
+ </para>
+ <para>
+ When no debug flag is set, this macro is ignored.
+ </para>
+ </section>
+
+ <section id="useful-functions-snd-bug-on">
+ <title><function>snd_BUG_ON()</function></title>
+ <para>
+ <function>snd_BUG_ON()</function> macro is similar with
+ <function>WARN_ON()</function> macro. For example,
<informalexample>
<programlisting>
<![CDATA[
- snd_assert(pointer != NULL, return -EINVAL);
+ snd_BUG_ON(!pointer);
]]>
</programlisting>
</informalexample>
- </para>
- <para>
- The first argument is the expression to evaluate, and the
- second argument is the action if it fails. When
- <constant>CONFIG_SND_DEBUG</constant>, is set, it will show an
- error message such as <computeroutput>BUG? (xxx)</computeroutput>
- together with stack trace.
- </para>
- <para>
- When no debug flag is set, this macro is ignored.
- </para>
- </section>
+ or it can be used as the condition,
+ <informalexample>
+ <programlisting>
+<![CDATA[
+ if (snd_BUG_ON(non_zero_is_bug))
+ return -EINVAL;
+]]>
+ </programlisting>
+ </informalexample>
- <section id="useful-functions-snd-bug">
- <title><function>snd_BUG()</function></title>
- <para>
- It shows the <computeroutput>BUG?</computeroutput> message and
- stack trace as well as <function>snd_assert</function> at the point.
- It's useful to show that a fatal error happens there.
</para>
+
<para>
- When no debug flag is set, this macro is ignored.
+ The macro takes an conditional expression to evaluate.
+ When <constant>CONFIG_SND_DEBUG</constant>, is set, the
+ expression is actually evaluated. If it's non-zero, it shows
+ the warning message such as
+ <computeroutput>BUG? (xxx)</computeroutput>
+ normally followed by stack trace. It returns the evaluated
+ value.
+ When no <constant>CONFIG_SND_DEBUG</constant> is set, this
+ macro always returns zero.
</para>
+
</section>
+
</chapter>