Be developer-friendly, 'cause OpenBSD devs like to:

cd /usr/src/share/man/man4; vi newdev.4 Makefile; make install; man newdev

When a manual is missing from an outdated database, let man(1)
show it anyway, using a KISS file system lookup as a fallback.
Requested by deraadt@.

87 new lines of code doesn't seem too much bloat to me.

Of course, keeping your mandoc.db(5) files up to date with makewhatis(8)
or weekly(8) is still required for apropos(1) to find your new pages.

1 files changed, 106 insertions, 5 deletions

diff --git a/main.c b/main.c
index 24e3537c..010dfaa4 100644
--- a/main.c
+++ b/main.c
@@ -1,4 +1,4 @@
-/*	$Id: main.c,v 1.212 2015/01/13 13:22:22 schwarze Exp $ */
+/*	$Id: main.c,v 1.213 2015/01/13 23:17:52 schwarze Exp $ */
 /*
  * Copyright (c) 2008-2012 Kristaps Dzonsons <kristaps@bsd.lv>
  * Copyright (c) 2010-2012, 2014, 2015 Ingo Schwarze <schwarze@openbsd.org>
@@ -82,6 +82,15 @@ struct	curparse {
 	char		  outopts[BUFSIZ]; /* buf of output opts */
 };
 
+#if HAVE_SQLITE3
+static	int		  fs_lookup(const struct manpaths *,
+				size_t ipath, const char *,
+				const char *, const char *,
+				struct manpage **, size_t *);
+static	void		  fs_search(const struct mansearch *,
+				const struct manpaths *, int, char**,
+				struct manpage **, size_t *);
+#endif
 static	int		  koptions(int *, char *);
 #if HAVE_SQLITE3
 int			  mandocdb(int, char**);
@@ -340,12 +349,11 @@ main(int argc, char *argv[])
 		mansearch_setup(1);
 		if( ! mansearch(&search, &paths, argc, argv, &res, &sz))
 			usage(search.argmode);
-		resp = res;
+
+		if (sz == 0 && search.argmode == ARG_NAME)
+			fs_search(&search, &paths, argc, argv, &res, &sz);
 
 		if (sz == 0) {
-			if (search.argmode == ARG_NAME)
-				fprintf(stderr, "%s: No entry for %s "
-				    "in the manual.\n", progname, argv[0]);
 			rc = MANDOCLEVEL_BADARG;
 			goto out;
 		}
@@ -364,6 +372,7 @@ main(int argc, char *argv[])
 
 		/* Iterate all matching manuals. */
 
+		resp = res;
 		for (i = 0; i < sz; i++) {
 			if (outmode == OUTMODE_FLN)
 				puts(res[i].file);
@@ -525,6 +534,98 @@ usage(enum argmode argmode)
 	exit((int)MANDOCLEVEL_BADARG);
 }
 
+#if HAVE_SQLITE3
+static int
+fs_lookup(const struct manpaths *paths, size_t ipath,
+	const char *sec, const char *arch, const char *name,
+	struct manpage **res, size_t *ressz)
+{
+	struct manpage	*page;
+	char		*file;
+	int		 form;
+
+	mandoc_asprintf(&file, "%s/man%s/%s.%s",
+	    paths->paths[ipath], sec, name, sec);
+	if (access(file, R_OK) != -1) {
+		form = FORM_SRC;
+		goto found;
+	}
+	free(file);
+
+	mandoc_asprintf(&file, "%s/cat%s/%s.0",
+	    paths->paths[ipath], sec, name);
+	if (access(file, R_OK) != -1) {
+		form = FORM_CAT;
+		goto found;
+	}
+	free(file);
+
+	if (arch != NULL) {
+		mandoc_asprintf(&file, "%s/man%s/%s/%s.%s",
+		    paths->paths[ipath], sec, arch, name, sec);
+		if (access(file, R_OK) != -1) {
+			form = FORM_SRC;
+			goto found;
+		}
+		free(file);
+	}
+	return(0);
+
+found:
+	fprintf(stderr, "%s: outdated mandoc.db lacks %s(%s) entry,\n"
+	    "     consider running  # makewhatis %s\n",
+	    progname, name, sec, paths->paths[ipath]);
+	
+	*res = mandoc_reallocarray(*res, ++*ressz, sizeof(struct manpage));
+	page = *res + (*ressz - 1);
+	page->file = file;
+	page->names = NULL;
+	page->output = NULL;
+	page->ipath = ipath;
+	page->bits = NAME_FILE & NAME_MASK;
+	page->sec = (*sec >= '1' && *sec <= '9') ? *sec - '1' + 1 : 10;
+	page->form = form;
+	return(1);
+}
+
+static void
+fs_search(const struct mansearch *cfg, const struct manpaths *paths,
+	int argc, char **argv, struct manpage **res, size_t *ressz)
+{
+	const char *const sections[] =
+	    {"1", "8", "6", "2", "3", "3p", "5", "7", "4", "9"};
+	const size_t nsec = sizeof(sections)/sizeof(sections[0]);
+
+	size_t		 ipath, isec, lastsz;
+
+	assert(cfg->argmode == ARG_NAME);
+
+	*res = NULL;
+	*ressz = lastsz = 0;
+	while (argc) {
+		for (ipath = 0; ipath < paths->sz; ipath++) {
+			if (cfg->sec != NULL) {
+				if (fs_lookup(paths, ipath, cfg->sec,
+				    cfg->arch, *argv, res, ressz) &&
+				    cfg->firstmatch)
+					return;
+			} else for (isec = 0; isec < nsec; isec++)
+				if (fs_lookup(paths, ipath, sections[isec],
+				    cfg->arch, *argv, res, ressz) &&
+				    cfg->firstmatch)
+					return;
+		}
+		if (*ressz == lastsz)
+			fprintf(stderr,
+			    "%s: No entry for %s in the manual.\n",
+			    progname, *argv);
+		lastsz = *ressz;
+		argv++;
+		argc--;
+	}
+}
+#endif
+
 static void
 parse(struct curparse *curp, int fd, const char *file,
 	enum mandoclevel *level)