Properly check for readdir/closedir() failures

Clear errno before calling readdir() and handle old MinGW errno bug
while adding full test coverage for readdir/closedir failures.

Backpatch through 8.4.

contrib/pg_archivecleanup/pg_archivecleanup.c

@@ -106,7 +106,7 @@ CleanupPriorWALFiles(void)
 
 	if ((xldir = opendir(archiveLocation)) != NULL)
 	{
-		while ((xlde = readdir(xldir)) != NULL)
+		while (errno = 0, (xlde = readdir(xldir)) != NULL)
 		{
 			strncpy(walfile, xlde->d_name, MAXPGPATH);
 			TrimExtension(walfile, additional_ext);
@@ -164,7 +164,19 @@ CleanupPriorWALFiles(void)
 				}
 			}
 		}
-		closedir(xldir);
+
+#ifdef WIN32
+		/* Bug in old Mingw dirent.c;  fixed in mingw-runtime-3.2, 2003-10-10 */
+		if (GetLastError() == ERROR_NO_MORE_FILES)
+			errno = 0;
+#endif
+
+		if (errno)
+			fprintf(stderr, "%s: could not read archive location \"%s\": %s\n",
+					progname, archiveLocation, strerror(errno));
+		if (closedir(xldir))
+			fprintf(stderr, "%s: could not close archive location \"%s\": %s\n",
+					progname, archiveLocation, strerror(errno));
 	}
 	else
 		fprintf(stderr, "%s: could not open archive location \"%s\": %s\n",

contrib/pg_standby/pg_standby.c

@@ -245,7 +245,7 @@ CustomizableCleanupPriorWALFiles(void)
 		 */
 		if ((xldir = opendir(archiveLocation)) != NULL)
 		{
-			while ((xlde = readdir(xldir)) != NULL)
+			while (errno = 0, (xlde = readdir(xldir)) != NULL)
 			{
 				/*
 				 * We ignore the timeline part of the XLOG segment identifiers
@@ -283,6 +283,16 @@ CustomizableCleanupPriorWALFiles(void)
 					}
 				}
 			}
+
+#ifdef WIN32
+			/* Bug in old Mingw dirent.c;  fixed in mingw-runtime-3.2, 2003-10-10 */
+			if (GetLastError() == ERROR_NO_MORE_FILES)
+				errno = 0;
+#endif
+
+			if (errno)
+				fprintf(stderr, "%s: could not read archive location \"%s\": %s\n",
+						progname, archiveLocation, strerror(errno));
 			if (debug)
 				fprintf(stderr, "\n");
 		}
@@ -290,7 +300,10 @@ CustomizableCleanupPriorWALFiles(void)
 			fprintf(stderr, "%s: could not open archive location \"%s\": %s\n",
 					progname, archiveLocation, strerror(errno));
 
-		closedir(xldir);
+		if (closedir(xldir))
+			fprintf(stderr, "%s: could not close archive location \"%s\": %s\n",
+					progname, archiveLocation, strerror(errno));
+
 		fflush(stderr);
 	}
 }

src/backend/storage/file/fd.c

@@ -1957,10 +1957,7 @@ ReadDir(DIR *dir, const char *dirname)
 		return dent;
 
 #ifdef WIN32
-	/*
+	/* Bug in old Mingw dirent.c;  fixed in mingw-runtime-3.2, 2003-10-10 */
-	 * This fix is in mingw cvs (runtime/mingwex/dirent.c rev 1.4), but not in
-	 * released version
-	 */
 	if (GetLastError() == ERROR_NO_MORE_FILES)
 		errno = 0;
 #endif

src/bin/initdb/initdb.c

@@ -565,10 +565,7 @@ walkdir(char *path, void (*action) (char *fname, bool isdir))
 	}
 
 #ifdef WIN32
-	/*
+	/* Bug in old Mingw dirent.c;  fixed in mingw-runtime-3.2, 2003-10-10 */
-	 * This fix is in mingw cvs (runtime/mingwex/dirent.c rev 1.4), but not in
-	 * released version
-	 */
 	if (GetLastError() == ERROR_NO_MORE_FILES)
 		errno = 0;
 #endif
@@ -580,7 +577,12 @@ walkdir(char *path, void (*action) (char *fname, bool isdir))
 		exit_nicely();
 	}
 
-	closedir(dir);
+	if (closedir(dir))
+	{
+		fprintf(stderr, _("%s: could not close directory \"%s\": %s\n"),
+				progname, path, strerror(errno));
+		exit_nicely();
+	}
 
 	/*
 	 * It's important to fsync the destination directory itself as individual

src/bin/pg_basebackup/pg_receivexlog.c

@@ -139,7 +139,7 @@ FindStreamingStart(uint32 *tli)
 		disconnect_and_exit(1);
 	}
 
-	while ((dirent = readdir(dir)) != NULL)
+	while (errno = 0, (dirent = readdir(dir)) != NULL)
 	{
 		uint32		tli;
 		XLogSegNo	segno;
@@ -209,7 +209,25 @@ FindStreamingStart(uint32 *tli)
 		}
 	}
 
-	closedir(dir);
+#ifdef WIN32
+	/* Bug in old Mingw dirent.c;  fixed in mingw-runtime-3.2, 2003-10-10 */
+	if (GetLastError() == ERROR_NO_MORE_FILES)
+		errno = 0;
+#endif
+
+	if (errno)
+	{
+		fprintf(stderr, _("%s: could not read directory \"%s\": %s\n"),
+				progname, basedir, strerror(errno));
+		disconnect_and_exit(1);
+	}
+
+	if (closedir(dir))
+	{
+		fprintf(stderr, _("%s: could not close directory \"%s\": %s\n"),
+				progname, basedir, strerror(errno));
+		disconnect_and_exit(1);
+	}
 
 	if (high_segno > 0)
 	{

src/bin/pg_dump/pg_backup_directory.c

@@ -177,7 +177,7 @@ InitArchiveFmt_Directory(ArchiveHandle *AH)
 				struct dirent *d;
 
 				is_empty = true;
-				while ((d = readdir(dir)))
+				while (errno = 0, (d = readdir(dir)))
 				{
 					if (strcmp(d->d_name, ".") != 0 && strcmp(d->d_name, "..") != 0)
 					{
@@ -185,7 +185,20 @@ InitArchiveFmt_Directory(ArchiveHandle *AH)
 						break;
 					}
 				}
-				closedir(dir);
+
+#ifdef WIN32
+				/* Bug in old Mingw dirent.c;  fixed in mingw-runtime-3.2, 2003-10-10 */
+				if (GetLastError() == ERROR_NO_MORE_FILES)
+					errno = 0;
+#endif
+
+				if (errno)
+					exit_horribly(modulename, "could not read directory \"%s\": %s\n",
+								  ctx->directory, strerror(errno));
+
+				if (closedir(dir))
+					exit_horribly(modulename, "could not close directory \"%s\": %s\n",
+								  ctx->directory, strerror(errno));
 			}
 		}
 

src/bin/pg_resetxlog/pg_resetxlog.c

@@ -821,8 +821,7 @@ FindEndOfXLOG(void)
 		exit(1);
 	}
 
-	errno = 0;
+	while (errno = 0, (xlde = readdir(xldir)) != NULL)
-	while ((xlde = readdir(xldir)) != NULL)
 	{
 		if (strlen(xlde->d_name) == 24 &&
 			strspn(xlde->d_name, "0123456789ABCDEF") == 24)
@@ -844,25 +843,27 @@ FindEndOfXLOG(void)
 			if (segno > newXlogSegNo)
 				newXlogSegNo = segno;
 		}
-		errno = 0;
 	}
 
 #ifdef WIN32
-	/*
+	/* Bug in old Mingw dirent.c;  fixed in mingw-runtime-3.2, 2003-10-10 */
-	 * This fix is in mingw cvs (runtime/mingwex/dirent.c rev 1.4), but not in
-	 * released version
-	 */
 	if (GetLastError() == ERROR_NO_MORE_FILES)
 		errno = 0;
 #endif
 
 	if (errno)
 	{
-		fprintf(stderr, _("%s: could not read from directory \"%s\": %s\n"),
+		fprintf(stderr, _("%s: could not read directory \"%s\": %s\n"),
+				progname, XLOGDIR, strerror(errno));
+		exit(1);
+	}
+
+	if (closedir(xldir))
+	{
+		fprintf(stderr, _("%s: could not close directory \"%s\": %s\n"),
 				progname, XLOGDIR, strerror(errno));
 		exit(1);
 	}
-	closedir(xldir);
 
 	/*
 	 * Finally, convert to new xlog seg size, and advance by one to ensure we
@@ -892,8 +893,7 @@ KillExistingXLOG(void)
 		exit(1);
 	}
 
-	errno = 0;
+	while (errno = 0, (xlde = readdir(xldir)) != NULL)
-	while ((xlde = readdir(xldir)) != NULL)
 	{
 		if (strlen(xlde->d_name) == 24 &&
 			strspn(xlde->d_name, "0123456789ABCDEF") == 24)
@@ -906,25 +906,27 @@ KillExistingXLOG(void)
 				exit(1);
 			}
 		}
-		errno = 0;
 	}
 
 #ifdef WIN32
-	/*
+	/* Bug in old Mingw dirent.c;  fixed in mingw-runtime-3.2, 2003-10-10 */
-	 * This fix is in mingw cvs (runtime/mingwex/dirent.c rev 1.4), but not in
-	 * released version
-	 */
 	if (GetLastError() == ERROR_NO_MORE_FILES)
 		errno = 0;
 #endif
 
 	if (errno)
 	{
-		fprintf(stderr, _("%s: could not read from directory \"%s\": %s\n"),
+		fprintf(stderr, _("%s: could not read directory \"%s\": %s\n"),
+				progname, XLOGDIR, strerror(errno));
+		exit(1);
+	}
+
+	if (closedir(xldir))
+	{
+		fprintf(stderr, _("%s: could not close directory \"%s\": %s\n"),
 				progname, XLOGDIR, strerror(errno));
 		exit(1);
 	}
-	closedir(xldir);
 }
 
 
@@ -948,8 +950,7 @@ KillExistingArchiveStatus(void)
 		exit(1);
 	}
 
-	errno = 0;
+	while (errno = 0, (xlde = readdir(xldir)) != NULL)
-	while ((xlde = readdir(xldir)) != NULL)
 	{
 		if (strspn(xlde->d_name, "0123456789ABCDEF") == 24 &&
 			(strcmp(xlde->d_name + 24, ".ready") == 0 ||
@@ -963,25 +964,27 @@ KillExistingArchiveStatus(void)
 				exit(1);
 			}
 		}
-		errno = 0;
 	}
 
 #ifdef WIN32
-	/*
+	/* Bug in old Mingw dirent.c;  fixed in mingw-runtime-3.2, 2003-10-10 */
-	 * This fix is in mingw cvs (runtime/mingwex/dirent.c rev 1.4), but not in
-	 * released version
-	 */
 	if (GetLastError() == ERROR_NO_MORE_FILES)
 		errno = 0;
 #endif
 
 	if (errno)
 	{
-		fprintf(stderr, _("%s: could not read from directory \"%s\": %s\n"),
+		fprintf(stderr, _("%s: could not read directory \"%s\": %s\n"),
+				progname, ARCHSTATDIR, strerror(errno));
+		exit(1);
+	}
+
+	if (closedir(xldir))
+	{
+		fprintf(stderr, _("%s: could not close directory \"%s\": %s\n"),
 				progname, ARCHSTATDIR, strerror(errno));
 		exit(1);
 	}
-	closedir(xldir);
 }
 
 

src/common/pgfnames.c

@@ -50,8 +50,7 @@ pgfnames(const char *path)
 
 	filenames = (char **) palloc(fnsize * sizeof(char *));
 
-	errno = 0;
+	while (errno = 0, (file = readdir(dir)) != NULL)
-	while ((file = readdir(dir)) != NULL)
 	{
 		if (strcmp(file->d_name, ".") != 0 && strcmp(file->d_name, "..") != 0)
 		{
@@ -63,14 +62,10 @@ pgfnames(const char *path)
 			}
 			filenames[numnames++] = pstrdup(file->d_name);
 		}
-		errno = 0;
 	}
 
 #ifdef WIN32
-	/*
+	/* Bug in old Mingw dirent.c;  fixed in mingw-runtime-3.2, 2003-10-10 */
-	 * This fix is in mingw cvs (runtime/mingwex/dirent.c rev 1.4), but not in
-	 * released version
-	 */
 	if (GetLastError() == ERROR_NO_MORE_FILES)
 		errno = 0;
 #endif
@@ -87,7 +82,15 @@ pgfnames(const char *path)
 
 	filenames[numnames] = NULL;
 
-	closedir(dir);
+	if (closedir(dir))
+	{
+#ifndef FRONTEND
+		elog(WARNING, "could not close directory \"%s\": %m", path);
+#else
+		fprintf(stderr, _("could not close directory \"%s\": %s\n"),
+				path, strerror(errno));
+#endif
+	}
 
 	return filenames;
 }

src/port/dirent.c

@@ -105,15 +105,19 @@ readdir(DIR *d)
 	strcpy(d->ret.d_name, fd.cFileName);		/* Both strings are MAX_PATH
 												 * long */
 	d->ret.d_namlen = strlen(d->ret.d_name);
+
 	return &d->ret;
 }
 
 int
 closedir(DIR *d)
 {
+	int ret = 0;
+
 	if (d->handle != INVALID_HANDLE_VALUE)
-		FindClose(d->handle);
+		ret = !FindClose(d->handle);
 	free(d->dirname);
 	free(d);
-	return 0;
+
+	return ret;
 }

src/port/pgcheckdir.c

@@ -33,14 +33,11 @@ pg_check_dir(const char *dir)
 	struct dirent *file;
 	bool		dot_found = false;
 
-	errno = 0;
-
 	chkdir = opendir(dir);
-
 	if (chkdir == NULL)
 		return (errno == ENOENT) ? 0 : -1;
 
-	while ((file = readdir(chkdir)) != NULL)
+	while (errno = 0, (file = readdir(chkdir)) != NULL)
 	{
 		if (strcmp(".", file->d_name) == 0 ||
 			strcmp("..", file->d_name) == 0)
@@ -68,17 +65,12 @@ pg_check_dir(const char *dir)
 	}
 
 #ifdef WIN32
-	/*
+	/* Bug in old Mingw dirent.c;  fixed in mingw-runtime-3.2, 2003-10-10 */
-	 * This fix is in mingw cvs (runtime/mingwex/dirent.c rev 1.4), but not in
-	 * released version
-	 */
 	if (GetLastError() == ERROR_NO_MORE_FILES)
 		errno = 0;
 #endif
 
-	closedir(chkdir);
+	if (errno || closedir(chkdir))
-
-	if (errno != 0)
 		result = -1;			/* some kind of I/O error? */
 
 	/* We report on dot-files if we _only_ find dot files */