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.

8 files changed, 98 insertions, 68 deletions

diff --git a/src/backend/storage/file/fd.c b/src/backend/storage/file/fd.c
index 436b901c20d..a2907957ae4 100644
--- a/src/backend/storage/file/fd.c
+++ b/src/backend/storage/file/fd.c
@@ -1901,11 +1901,7 @@ ReadDir(DIR *dir, const char *dirname)
 		return dent;
 
 #ifdef WIN32
-
-	/*
-	 * This fix is in mingw cvs (runtime/mingwex/dirent.c rev 1.4), but not in
-	 * released version
-	 */
+	/* Bug in old Mingw dirent.c;  fixed in mingw-runtime-3.2, 2003-10-10 */
 	if (GetLastError() == ERROR_NO_MORE_FILES)
 		errno = 0;
 #endif
diff --git a/src/bin/initdb/initdb.c b/src/bin/initdb/initdb.c
index 5fc7291ff69..c440f8f3a18 100644
--- a/src/bin/initdb/initdb.c
+++ b/src/bin/initdb/initdb.c
@@ -557,11 +557,7 @@ walkdir(char *path, void (*action) (char *fname, bool isdir))
 	}
 
 #ifdef WIN32
-
-	/*
-	 * This fix is in mingw cvs (runtime/mingwex/dirent.c rev 1.4), but not in
-	 * released version
-	 */
+	/* Bug in old Mingw dirent.c;  fixed in mingw-runtime-3.2, 2003-10-10 */
 	if (GetLastError() == ERROR_NO_MORE_FILES)
 		errno = 0;
 #endif
@@ -573,7 +569,12 @@ 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
diff --git a/src/bin/pg_basebackup/pg_receivexlog.c b/src/bin/pg_basebackup/pg_receivexlog.c
index 5738c0e6e6a..8d9f00e930f 100644
--- a/src/bin/pg_basebackup/pg_receivexlog.c
+++ b/src/bin/pg_basebackup/pg_receivexlog.c
@@ -138,7 +138,7 @@ FindStreamingStart(uint32 *tli)
 		disconnect_and_exit(1);
 	}
 
-	while ((dirent = readdir(dir)) != NULL)
+	while (errno = 0, (dirent = readdir(dir)) != NULL)
 	{
 		uint32		tli;
 		XLogSegNo	segno;
@@ -208,7 +208,25 @@ 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)
 	{
diff --git a/src/bin/pg_dump/pg_backup_directory.c b/src/bin/pg_dump/pg_backup_directory.c
index f803186a2e6..a8bcd590ec1 100644
--- a/src/bin/pg_dump/pg_backup_directory.c
+++ b/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));
 			}
 		}
 
diff --git a/src/bin/pg_resetxlog/pg_resetxlog.c b/src/bin/pg_resetxlog/pg_resetxlog.c
index cd003f41c99..e44462adcef 100644
--- a/src/bin/pg_resetxlog/pg_resetxlog.c
+++ b/src/bin/pg_resetxlog/pg_resetxlog.c
@@ -765,8 +765,7 @@ FindEndOfXLOG(void)
 		exit(1);
 	}
 
-	errno = 0;
-	while ((xlde = readdir(xldir)) != NULL)
+	while (errno = 0, (xlde = readdir(xldir)) != NULL)
 	{
 		if (strlen(xlde->d_name) == 24 &&
 			strspn(xlde->d_name, "0123456789ABCDEF") == 24)
@@ -788,25 +787,27 @@ FindEndOfXLOG(void)
 			if (segno > newXlogSegNo)
 				newXlogSegNo = segno;
 		}
-		errno = 0;
 	}
-#ifdef WIN32
 
-	/*
-	 * This fix is in mingw cvs (runtime/mingwex/dirent.c rev 1.4), but not in
-	 * released version
-	 */
+#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 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
@@ -836,8 +837,7 @@ KillExistingXLOG(void)
 		exit(1);
 	}
 
-	errno = 0;
-	while ((xlde = readdir(xldir)) != NULL)
+	while (errno = 0, (xlde = readdir(xldir)) != NULL)
 	{
 		if (strlen(xlde->d_name) == 24 &&
 			strspn(xlde->d_name, "0123456789ABCDEF") == 24)
@@ -850,25 +850,27 @@ KillExistingXLOG(void)
 				exit(1);
 			}
 		}
-		errno = 0;
 	}
-#ifdef WIN32
 
-	/*
-	 * This fix is in mingw cvs (runtime/mingwex/dirent.c rev 1.4), but not in
-	 * released version
-	 */
+#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 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);
 }
 
 
@@ -892,8 +894,7 @@ KillExistingArchiveStatus(void)
 		exit(1);
 	}
 
-	errno = 0;
-	while ((xlde = readdir(xldir)) != NULL)
+	while (errno = 0, (xlde = readdir(xldir)) != NULL)
 	{
 		if (strspn(xlde->d_name, "0123456789ABCDEF") == 24 &&
 			(strcmp(xlde->d_name + 24, ".ready") == 0 ||
@@ -907,25 +908,27 @@ KillExistingArchiveStatus(void)
 				exit(1);
 			}
 		}
-		errno = 0;
 	}
-#ifdef WIN32
 
-	/*
-	 * This fix is in mingw cvs (runtime/mingwex/dirent.c rev 1.4), but not in
-	 * released version
-	 */
+#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 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);
 }
 
 
diff --git a/src/port/dirent.c b/src/port/dirent.c
index 9298e63f4d2..64de4414c29 100644
--- a/src/port/dirent.c
+++ b/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;
 }
diff --git a/src/port/dirmod.c b/src/port/dirmod.c
index 5dd0983a2de..fde9736f4a0 100644
--- a/src/port/dirmod.c
+++ b/src/port/dirmod.c
@@ -382,8 +382,7 @@ pgfnames(const char *path)
 
 	filenames = (char **) palloc(fnsize * sizeof(char *));
 
-	errno = 0;
-	while ((file = readdir(dir)) != NULL)
+	while (errno = 0, (file = readdir(dir)) != NULL)
 	{
 		if (strcmp(file->d_name, ".") != 0 && strcmp(file->d_name, "..") != 0)
 		{
@@ -395,17 +394,14 @@ pgfnames(const char *path)
 			}
 			filenames[numnames++] = pstrdup(file->d_name);
 		}
-		errno = 0;
 	}
-#ifdef WIN32
 
-	/*
-	 * This fix is in mingw cvs (runtime/mingwex/dirent.c rev 1.4), but not in
-	 * released version
-	 */
+#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)
 	{
 #ifndef FRONTEND
@@ -418,7 +414,15 @@ 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;
 }
diff --git a/src/port/pgcheckdir.c b/src/port/pgcheckdir.c
index 9d80192a8e6..a68c7a3dfa3 100644
--- a/src/port/pgcheckdir.c
+++ b/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)
@@ -68,18 +65,12 @@ pg_check_dir(const char *dir)
 	}
 
 #ifdef WIN32
-
-	/*
-	 * This fix is in mingw cvs (runtime/mingwex/dirent.c rev 1.4), but not in
-	 * released version
-	 */
+	/* Bug in old Mingw dirent.c;  fixed in mingw-runtime-3.2, 2003-10-10 */
 	if (GetLastError() == ERROR_NO_MORE_FILES)
 		errno = 0;
 #endif
 
-	closedir(chkdir);
-
-	if (errno != 0)
+	if (errno || closedir(chkdir))
 		result = -1;			/* some kind of I/O error? */
 
 	/* We report on dot-files if we _only_ find dot files */