kernel-doc: improve "no structured comments found" error

When using '!Ffile function' in a docbook template, and the function no
longer exists, you get a "no structured comments found" error from the
kernel-doc processing script.  It's useful to know which functions it was
looking for, so print them out in this case.  Also do the same for '!Pfile
doc-section'

The same error also happens when using '!Efile' when some exported
functions aren't documented (in the same file.) There's a very large
number of such functions though, so don't print the message in this case
-- right now it would give ~850 messages.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Cc: Rob Landley <rob@landley.net>
Cc: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

scripts/docproc.c

@@ -72,6 +72,7 @@ FILELINE * docsection;
 #define FUNCTION      "-function"
 #define NOFUNCTION    "-nofunction"
 #define NODOCSECTIONS "-no-doc-sections"
+#define SHOWNOTFOUND  "-show-not-found"
 
 static char *srctree, *kernsrctree;
 
@@ -294,6 +295,7 @@ static void singfunc(char * filename, char * line)
         int startofsym = 1;
 	vec[idx++] = KERNELDOC;
 	vec[idx++] = DOCBOOK;
+	vec[idx++] = SHOWNOTFOUND;
 
         /* Split line up in individual parameters preceded by FUNCTION */
         for (i=0; line[i]; i++) {
@@ -325,7 +327,8 @@ static void singfunc(char * filename, char * line)
  */
 static void docsect(char *filename, char *line)
 {
-	char *vec[6]; /* kerneldoc -docbook -function "section" file NULL */
+	/* kerneldoc -docbook -show-not-found -function "section" file NULL */
+	char *vec[7];
 	char *s;
 
 	for (s = line; *s; s++)
@@ -341,10 +344,11 @@ static void docsect(char *filename, char *line)
 
 	vec[0] = KERNELDOC;
 	vec[1] = DOCBOOK;
-	vec[2] = FUNCTION;
-	vec[3] = line;
-	vec[4] = filename;
-	vec[5] = NULL;
+	vec[2] = SHOWNOTFOUND;
+	vec[3] = FUNCTION;
+	vec[4] = line;
+	vec[5] = filename;
+	vec[6] = NULL;
 	exec_kernel_doc(vec);
 }
 

scripts/kernel-doc

@@ -257,6 +257,7 @@ my $man_date = ('January', 'February', 'March', 'April', 'May', 'June',
 		'July', 'August', 'September', 'October',
 		'November', 'December')[(localtime)[4]] .
   " " . ((localtime)[5]+1900);
+my $show_not_found = 0;
 
 # Essentially these are globals.
 # They probably want to be tidied up, made more localised or something.
@@ -369,6 +370,8 @@ while ($ARGV[0] =~ m/^-(.*)/) {
 	usage();
     } elsif ($cmd eq '-no-doc-sections') {
 	    $no_doc_sections = 1;
+    } elsif ($cmd eq '-show-not-found') {
+	$show_not_found = 1;
     }
 }
 
@@ -2536,6 +2539,9 @@ sub process_file($) {
     }
     if ($initial_section_counter == $section_counter) {
 	print STDERR "Warning(${file}): no structured comments found\n";
+	if (($function_only == 1) && ($show_not_found == 1)) {
+	    print STDERR "    Was looking for '$_'.\n" for keys %function_table;
+	}
 	if ($output_mode eq "xml") {
 	    # The template wants at least one RefEntry here; make one.
 	    print "<refentry>\n";