Clear dform and dsec when exiting a first-level directory in treescan().

Fixes a segfault reported by bentley@.
While here, do some style cleanup in the same function.

1 files changed, 23 insertions, 20 deletions

diff --git a/usr.bin/mandoc/mandocdb.c b/usr.bin/mandoc/mandocdb.c
index 7f8c67b18d3..809ad999bce 100644
--- a/usr.bin/mandoc/mandocdb.c
+++ b/usr.bin/mandoc/mandocdb.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: mandocdb.c,v 1.152 2015/10/12 00:07:27 schwarze Exp $ */
+/*	$OpenBSD: mandocdb.c,v 1.153 2015/10/12 00:32:37 schwarze Exp $ */
 /*
  * Copyright (c) 2011, 2012 Kristaps Dzonsons <kristaps@bsd.lv>
  * Copyright (c) 2011-2015 Ingo Schwarze <schwarze@openbsd.org>
@@ -574,7 +574,7 @@ treescan(void)
 
 	f = fts_open((char * const *)argv,
 	    FTS_PHYSICAL | FTS_NOCHDIR, NULL);
-	if (NULL == f) {
+	if (f == NULL) {
 		exitcode = (int)MANDOCLEVEL_SYSERR;
 		say("", "&fts_open");
 		return 0;
@@ -583,7 +583,7 @@ treescan(void)
 	dsec = arch = NULL;
 	dform = FORM_NONE;
 
-	while (NULL != (ff = fts_read(f))) {
+	while ((ff = fts_read(f)) != NULL) {
 		path = ff->fts_path + 2;
 		switch (ff->fts_info) {
 
@@ -592,7 +592,7 @@ treescan(void)
 		 * then get handled just like regular files.
 		 */
 		case FTS_SL:
-			if (NULL == realpath(path, buf)) {
+			if (realpath(path, buf) == NULL) {
 				if (warnings)
 					say(path, "&realpath");
 				continue;
@@ -603,7 +603,7 @@ treescan(void)
 				continue;
 			}
 			/* Use logical inode to avoid mpages dupe. */
-			if (-1 == stat(path, ff->fts_statp)) {
+			if (stat(path, ff->fts_statp) == -1) {
 				if (warnings)
 					say(path, "&stat");
 				continue;
@@ -615,7 +615,7 @@ treescan(void)
 		 * stored directory data and handling the filename.
 		 */
 		case FTS_F:
-			if (0 == strcmp(path, MANDOC_DB))
+			if ( ! strcmp(path, MANDOC_DB))
 				continue;
 			if ( ! use_all && ff->fts_level < 2) {
 				if (warnings)
@@ -624,37 +624,37 @@ treescan(void)
 			}
 			gzip = 0;
 			fsec = NULL;
-			while (NULL == fsec) {
+			while (fsec == NULL) {
 				fsec = strrchr(ff->fts_name, '.');
-				if (NULL == fsec || strcmp(fsec+1, "gz"))
+				if (fsec == NULL || strcmp(fsec+1, "gz"))
 					break;
 				gzip = 1;
 				*fsec = '\0';
 				fsec = NULL;
 			}
-			if (NULL == fsec) {
+			if (fsec == NULL) {
 				if ( ! use_all) {
 					if (warnings)
 						say(path,
 						    "No filename suffix");
 					continue;
 				}
-			} else if (0 == strcmp(++fsec, "html")) {
+			} else if ( ! strcmp(++fsec, "html")) {
 				if (warnings)
 					say(path, "Skip html");
 				continue;
-			} else if (0 == strcmp(fsec, "ps")) {
+			} else if ( ! strcmp(fsec, "ps")) {
 				if (warnings)
 					say(path, "Skip ps");
 				continue;
-			} else if (0 == strcmp(fsec, "pdf")) {
+			} else if ( ! strcmp(fsec, "pdf")) {
 				if (warnings)
 					say(path, "Skip pdf");
 				continue;
 			} else if ( ! use_all &&
-			    ((FORM_SRC == dform &&
+			    ((dform == FORM_SRC &&
 			      strncmp(fsec, dsec, strlen(dsec))) ||
-			     (FORM_CAT == dform && strcmp(fsec, "0")))) {
+			     (dform == FORM_CAT && strcmp(fsec, "0")))) {
 				if (warnings)
 					say(path, "Wrong filename suffix");
 				continue;
@@ -699,13 +699,16 @@ treescan(void)
 			 * If we're not in use_all, enforce it.
 			 */
 			cp = ff->fts_name;
-			if (FTS_DP == ff->fts_info)
+			if (ff->fts_info == FTS_DP) {
+				dform = FORM_NONE;
+				dsec = NULL;
 				break;
+			}
 
-			if (0 == strncmp(cp, "man", 3)) {
+			if ( ! strncmp(cp, "man", 3)) {
 				dform = FORM_SRC;
 				dsec = cp + 3;
-			} else if (0 == strncmp(cp, "cat", 3)) {
+			} else if ( ! strncmp(cp, "cat", 3)) {
 				dform = FORM_CAT;
 				dsec = cp + 3;
 			} else {
@@ -713,7 +716,7 @@ treescan(void)
 				dsec = NULL;
 			}
 
-			if (NULL != dsec || use_all)
+			if (dsec != NULL || use_all)
 				break;
 
 			if (warnings)
@@ -725,13 +728,13 @@ treescan(void)
 			 * Possibly our architecture.
 			 * If we're descending, keep tabs on it.
 			 */
-			if (FTS_DP != ff->fts_info && NULL != dsec)
+			if (ff->fts_info != FTS_DP && dsec != NULL)
 				arch = ff->fts_name;
 			else
 				arch = NULL;
 			break;
 		default:
-			if (FTS_DP == ff->fts_info || use_all)
+			if (ff->fts_info == FTS_DP || use_all)
 				break;
 			if (warnings)
 				say(path, "Extraneous directory part");