Re: [PATCH] Add kerneldoc for flush_scheduled_work()

[Johannes Weiner <hannes@cmpxchg.org>]

On Wed, Aug 19, 2009 at 04:21:23PM -0700, Randy Dunlap wrote:
> Johannes Weiner wrote:
> >> Yeah, it's the terminating **/ which matches $doc_cont.  I will try to
> >> send an updated version this evening.
> > 
> > I got completely rid of the extra re.  Just parse a non-empty content
> > line following the declaration purpose immediately as continuation.
> > 
> > It survives make htmldocs, the scsi_exit_devinfo() doc looks okay and
> > for stuff that had continuation lines before, it does what's expected
> > - e.g. for the doc of kernel/sched.c::init_sd_power_savings_stats().
> > 
> > It behaves differently for broken docs
> > (mm/page_alloc.c::calculate_zone_inactive_ratio e.g.), but that
> > shouldn't matter.
> 
> Right, no problem on that one (for which I sent Andrew a patch some
> time ago).
> 
> > I didn't find any other misbehaviour when checking random samples.
> 
> It's very close.  I only checked/compared one docbook: mac80211.
> There is some kind of paragraph end handling difference.
> 
> In processing include/net/mac80211.h, struct ieee80211_tx_info,
> without the patch, it ends with:
> 
> This structure is placed in skb->cb for three uses: (1) mac80211 TX control - mac80211 tells the driver what to do (2) driver internal use (if applicable) (3) TX status information - driver tells mac80211 what happened
> 
> The TX control's sta pointer is only valid during the ->tx call, it may be NULL.
> 
> and with the patch, those 2 paragraphs are run together:
> 
> This structure is placed in skb->cb for three uses: (1) mac80211 TX control - mac80211 tells the driver what to do (2) driver internal use (if applicable) (3) TX status information - driver tells mac80211 what happened The TX control's sta pointer is only valid during the ->tx call, it may be NULL.

Yeah, I forgot to actually collect empty lines in the documentation
bodies when changing that conditional.  Stupid.  I fixed it in the
attached version.

---
From: Johannes Weiner <hannes@cmpxchg.org>
Subject: kernel-doc: allow multi-line declaration purpose descriptions

Allow the short description after symbol name and dash in a kernel-doc
comment to span multiple lines, e.g. like this:

	/**
	 * unmap_mapping_range - unmap the portion of all mmaps in the
	 *	specified address_space corresponding to the specified
	 *	page range in the underlying file.
	 * @mapping: the address space containing mmaps to be unmapped.
	 * ...
	 */

The short description ends with a parameter description, an empty line
or the end of the comment block.

Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
---

diff --git a/Documentation/kernel-doc-nano-HOWTO.txt b/Documentation/kernel-doc-nano-HOWTO.txt
index 4d04572..348b9e5 100644
--- a/Documentation/kernel-doc-nano-HOWTO.txt
+++ b/Documentation/kernel-doc-nano-HOWTO.txt
@@ -66,7 +66,9 @@ Example kernel-doc function comment:
  * The longer description can have multiple paragraphs.
  */
 
-The first line, with the short description, must be on a single line.
+The short description following the subject can span multiple lines
+and ends with an @argument description, an empty line or the end of
+the comment block.
 
 The @argument descriptions must begin on the very next line following
 this opening short function description line, with no intervening
diff --git a/scripts/kernel-doc b/scripts/kernel-doc
index b52d340..d8b3641 100755
--- a/scripts/kernel-doc
+++ b/scripts/kernel-doc
@@ -1995,6 +1995,7 @@ sub process_file($) {
     my $identifier;
     my $func;
     my $descr;
+    my $in_purpose = 0;
     my $initial_section_counter = $section_counter;
 
     if (defined($ENV{'SRCTREE'})) {
@@ -2044,6 +2045,7 @@ sub process_file($) {
 		    $descr =~ s/\s*$//;
 		    $descr =~ s/\s+/ /;
 		    $declaration_purpose = xml_escape($descr);
+		    $in_purpose = 1;
 		} else {
 		    $declaration_purpose = "";
 		}
@@ -2090,6 +2092,7 @@ sub process_file($) {
 		}
 
 		$in_doc_sect = 1;
+		$in_purpose = 0;
 		$contents = $newcontents;
 		if ($contents ne "") {
 		    while ((substr($contents, 0, 1) eq " ") ||
@@ -2119,11 +2122,19 @@ sub process_file($) {
 	    } elsif (/$doc_content/) {
 		# miguel-style comment kludge, look for blank lines after
 		# @parameter line to signify start of description
-		if ($1 eq "" &&
-			($section =~ m/^@/ || $section eq $section_context)) {
-		    dump_section($file, $section, xml_escape($contents));
-		    $section = $section_default;
-		    $contents = "";
+		if ($1 eq "") {
+		    if ($section =~ m/^@/ || $section eq $section_context) {
+			dump_section($file, $section, xml_escape($contents));
+			$section = $section_default;
+			$contents = "";
+		    } else {
+			$contents .= "\n";
+		    }
+		    $in_purpose = 0;
+		} elsif ($in_purpose == 1) {
+		    # Continued declaration purpose
+		    chomp($declaration_purpose);
+		    $declaration_purpose .= " " . $1;
 		} else {
 		    $contents .= $1 . "\n";
 		}