Fix new warnings from GCC 7

This addresses the new warning types -Wformat-truncation
-Wformat-overflow that are part of -Wall, via -Wformat, in GCC 7.

Author: petere

contrib/pg_standby/pg_standby.c

@@ -57,7 +57,7 @@ char	   *xlogFilePath;		/* where we are going to restore to */
 char	   *nextWALFileName;	/* the file we need to get from archive */
 char	   *restartWALFileName; /* the file from which we can restart restore */
 char	   *priorWALFileName;	/* the file we need to get from archive */
-char		WALFilePath[MAXPGPATH];		/* the file path including archive */
+char		WALFilePath[MAXPGPATH * 2];		/* the file path including archive */
 char		restoreCommand[MAXPGPATH];	/* run this to restore */
 char		exclusiveCleanupFileName[MAXFNAMELEN];		/* the file we need to
 														 * get from archive */
@@ -259,9 +259,9 @@ CustomizableCleanupPriorWALFiles(void)
 				  strcmp(xlde->d_name + 8, exclusiveCleanupFileName + 8) < 0)
 				{
 #ifdef WIN32
-					snprintf(WALFilePath, MAXPGPATH, "%s\\%s", archiveLocation, xlde->d_name);
+					snprintf(WALFilePath, sizeof(WALFilePath), "%s\\%s", archiveLocation, xlde->d_name);
 #else
-					snprintf(WALFilePath, MAXPGPATH, "%s/%s", archiveLocation, xlde->d_name);
+					snprintf(WALFilePath, sizeof(WALFilePath), "%s/%s", archiveLocation, xlde->d_name);
 #endif
 
 					if (debug)

src/backend/access/heap/rewriteheap.c

@@ -1194,7 +1194,7 @@ CheckPointLogicalRewriteHeap(void)
 	XLogRecPtr	redo;
 	DIR		   *mappings_dir;
 	struct dirent *mapping_de;
-	char		path[MAXPGPATH];
+	char		path[MAXPGPATH + 20];
 
 	/*
 	 * We start of with a minimum of the last redo pointer. No new decoding
@@ -1225,7 +1225,7 @@ CheckPointLogicalRewriteHeap(void)
 			strcmp(mapping_de->d_name, "..") == 0)
 			continue;
 
-		snprintf(path, MAXPGPATH, "pg_logical/mappings/%s", mapping_de->d_name);
+		snprintf(path, sizeof(path), "pg_logical/mappings/%s", mapping_de->d_name);
 		if (lstat(path, &statbuf) == 0 && !S_ISREG(statbuf.st_mode))
 			continue;
 

src/backend/access/transam/xlog.c

@@ -3941,7 +3941,7 @@ CleanupBackupHistory(void)
 {
 	DIR		   *xldir;
 	struct dirent *xlde;
-	char		path[MAXPGPATH];
+	char		path[MAXPGPATH + sizeof(XLOGDIR)];
 
 	xldir = AllocateDir(XLOGDIR);
 	if (xldir == NULL)
@@ -3959,7 +3959,7 @@ CleanupBackupHistory(void)
 				ereport(DEBUG2,
 				(errmsg("removing transaction log backup history file \"%s\"",
 						xlde->d_name)));
-				snprintf(path, MAXPGPATH, XLOGDIR "/%s", xlde->d_name);
+				snprintf(path, sizeof(path), XLOGDIR "/%s", xlde->d_name);
 				unlink(path);
 				XLogArchiveCleanup(xlde->d_name);
 			}
@@ -10061,7 +10061,7 @@ do_pg_start_backup(const char *backupidstr, bool fast, TimeLineID *starttli_p,
 		/* Collect information about all tablespaces */
 		while ((de = ReadDir(tblspcdir, "pg_tblspc")) != NULL)
 		{
-			char		fullpath[MAXPGPATH];
+			char		fullpath[MAXPGPATH + 10];
 			char		linkpath[MAXPGPATH];
 			char	   *relpath = NULL;
 			int			rllen;

src/backend/postmaster/pgstat.c

@@ -569,7 +569,7 @@ pgstat_reset_remove_files(const char *directory)
 {
 	DIR		   *dir;
 	struct dirent *entry;
-	char		fname[MAXPGPATH];
+	char		fname[MAXPGPATH * 2];
 
 	dir = AllocateDir(directory);
 	while ((entry = ReadDir(dir, directory)) != NULL)
@@ -599,7 +599,7 @@ pgstat_reset_remove_files(const char *directory)
 			strcmp(entry->d_name + nchars, "stat") != 0)
 			continue;
 
-		snprintf(fname, MAXPGPATH, "%s/%s", directory,
+		snprintf(fname, sizeof(fname), "%s/%s", directory,
 				 entry->d_name);
 		unlink(fname);
 	}

src/backend/replication/basebackup.c

@@ -888,7 +888,7 @@ sendDir(char *path, int basepathlen, bool sizeonly, List *tablespaces,
 {
 	DIR		   *dir;
 	struct dirent *de;
-	char		pathbuf[MAXPGPATH];
+	char		pathbuf[MAXPGPATH * 2];
 	struct stat statbuf;
 	int64		size = 0;
 
@@ -940,7 +940,7 @@ sendDir(char *path, int basepathlen, bool sizeonly, List *tablespaces,
 						 "and should not be used. "
 						 "Try taking another online backup.")));
 
-		snprintf(pathbuf, MAXPGPATH, "%s/%s", path, de->d_name);
+		snprintf(pathbuf, sizeof(pathbuf), "%s/%s", path, de->d_name);
 
 		/* Skip postmaster.pid and postmaster.opts in the data directory */
 		if (strcmp(pathbuf, "./postmaster.pid") == 0 ||

src/backend/replication/logical/reorderbuffer.c

@@ -2650,7 +2650,7 @@ StartupReorderBuffer(void)
 	while ((logical_de = ReadDir(logical_dir, "pg_replslot")) != NULL)
 	{
 		struct stat statbuf;
-		char		path[MAXPGPATH];
+		char		path[MAXPGPATH * 2 + 12];
 
 		if (strcmp(logical_de->d_name, ".") == 0 ||
 			strcmp(logical_de->d_name, "..") == 0)

src/backend/replication/logical/snapbuild.c

@@ -1831,7 +1831,7 @@ CheckPointSnapBuild(void)
 	XLogRecPtr	redo;
 	DIR		   *snap_dir;
 	struct dirent *snap_de;
-	char		path[MAXPGPATH];
+	char		path[MAXPGPATH + 21];
 
 	/*
 	 * We start of with a minimum of the last redo pointer. No new replication
@@ -1858,7 +1858,7 @@ CheckPointSnapBuild(void)
 			strcmp(snap_de->d_name, "..") == 0)
 			continue;
 
-		snprintf(path, MAXPGPATH, "pg_logical/snapshots/%s", snap_de->d_name);
+		snprintf(path, sizeof(path), "pg_logical/snapshots/%s", snap_de->d_name);
 
 		if (lstat(path, &statbuf) == 0 && !S_ISREG(statbuf.st_mode))
 		{

src/backend/replication/slot.c

@@ -918,13 +918,13 @@ StartupReplicationSlots(void)
 	while ((replication_de = ReadDir(replication_dir, "pg_replslot")) != NULL)
 	{
 		struct stat statbuf;
-		char		path[MAXPGPATH];
+		char		path[MAXPGPATH + 12];
 
 		if (strcmp(replication_de->d_name, ".") == 0 ||
 			strcmp(replication_de->d_name, "..") == 0)
 			continue;
 
-		snprintf(path, MAXPGPATH, "pg_replslot/%s", replication_de->d_name);
+		snprintf(path, sizeof(path), "pg_replslot/%s", replication_de->d_name);
 
 		/* we're only creating directories here, skip if it's not our's */
 		if (lstat(path, &statbuf) == 0 && !S_ISDIR(statbuf.st_mode))
@@ -1148,7 +1148,7 @@ RestoreSlotFromDisk(const char *name)
 {
 	ReplicationSlotOnDisk cp;
 	int			i;
-	char		path[MAXPGPATH];
+	char		path[MAXPGPATH + 22];
 	int			fd;
 	bool		restored = false;
 	int			readBytes;

src/backend/storage/file/copydir.c

@@ -38,8 +38,8 @@ copydir(char *fromdir, char *todir, bool recurse)
 {
 	DIR		   *xldir;
 	struct dirent *xlde;
-	char		fromfile[MAXPGPATH];
-	char		tofile[MAXPGPATH];
+	char		fromfile[MAXPGPATH * 2];
+	char		tofile[MAXPGPATH * 2];
 
 	if (mkdir(todir, S_IRWXU) != 0)
 		ereport(ERROR,
@@ -63,8 +63,8 @@ copydir(char *fromdir, char *todir, bool recurse)
 			strcmp(xlde->d_name, "..") == 0)
 			continue;
 
-		snprintf(fromfile, MAXPGPATH, "%s/%s", fromdir, xlde->d_name);
-		snprintf(tofile, MAXPGPATH, "%s/%s", todir, xlde->d_name);
+		snprintf(fromfile, sizeof(fromfile), "%s/%s", fromdir, xlde->d_name);
+		snprintf(tofile, sizeof(tofile), "%s/%s", todir, xlde->d_name);
 
 		if (lstat(fromfile, &fst) < 0)
 			ereport(ERROR,
@@ -103,7 +103,7 @@ copydir(char *fromdir, char *todir, bool recurse)
 			strcmp(xlde->d_name, "..") == 0)
 			continue;
 
-		snprintf(tofile, MAXPGPATH, "%s/%s", todir, xlde->d_name);
+		snprintf(tofile, sizeof(tofile), "%s/%s", todir, xlde->d_name);
 
 		/*
 		 * We don't need to sync subdirectories here since the recursive

src/backend/storage/file/fd.c

@@ -2654,7 +2654,7 @@ CleanupTempFiles(bool isProcExit)
 void
 RemovePgTempFiles(void)
 {
-	char		temp_path[MAXPGPATH];
+	char		temp_path[MAXPGPATH + 10 + sizeof(TABLESPACE_VERSION_DIRECTORY) + sizeof(PG_TEMP_FILES_DIR)];
 	DIR		   *spc_dir;
 	struct dirent *spc_de;
 
@@ -2702,7 +2702,7 @@ RemovePgTempFilesInDir(const char *tmpdirname)
 {
 	DIR		   *temp_dir;
 	struct dirent *temp_de;
-	char		rm_path[MAXPGPATH];
+	char		rm_path[MAXPGPATH * 2];
 
 	temp_dir = AllocateDir(tmpdirname);
 	if (temp_dir == NULL)
@@ -2743,7 +2743,7 @@ RemovePgTempRelationFiles(const char *tsdirname)
 {
 	DIR		   *ts_dir;
 	struct dirent *de;
-	char		dbspace_path[MAXPGPATH];
+	char		dbspace_path[MAXPGPATH * 2];
 
 	ts_dir = AllocateDir(tsdirname);
 	if (ts_dir == NULL)
@@ -2784,7 +2784,7 @@ RemovePgTempRelationFilesInDbspace(const char *dbspacedirname)
 {
 	DIR		   *dbspace_dir;
 	struct dirent *de;
-	char		rm_path[MAXPGPATH];
+	char		rm_path[MAXPGPATH * 2];
 
 	dbspace_dir = AllocateDir(dbspacedirname);
 	if (dbspace_dir == NULL)
@@ -2971,7 +2971,7 @@ walkdir(const char *path,
 
 	while ((de = ReadDirExtended(dir, path, elevel)) != NULL)
 	{
-		char		subpath[MAXPGPATH];
+		char		subpath[MAXPGPATH * 2];
 		struct stat fst;
 		int			sret;
 
@@ -2981,7 +2981,7 @@ walkdir(const char *path,
 			strcmp(de->d_name, "..") == 0)
 			continue;
 
-		snprintf(subpath, MAXPGPATH, "%s/%s", path, de->d_name);
+		snprintf(subpath, sizeof(subpath), "%s/%s", path, de->d_name);
 
 		if (process_symlinks)
 			sret = stat(subpath, &fst);

src/backend/storage/file/reinit.c

@@ -48,7 +48,7 @@ typedef struct
 void
 ResetUnloggedRelations(int op)
 {
-	char		temp_path[MAXPGPATH];
+	char		temp_path[MAXPGPATH + 10 + sizeof(TABLESPACE_VERSION_DIRECTORY)];
 	DIR		   *spc_dir;
 	struct dirent *spc_de;
 	MemoryContext tmpctx,
@@ -104,7 +104,7 @@ ResetUnloggedRelationsInTablespaceDir(const char *tsdirname, int op)
 {
 	DIR		   *ts_dir;
 	struct dirent *de;
-	char		dbspace_path[MAXPGPATH];
+	char		dbspace_path[MAXPGPATH * 2];
 
 	ts_dir = AllocateDir(tsdirname);
 	if (ts_dir == NULL)
@@ -145,7 +145,7 @@ ResetUnloggedRelationsInDbspaceDir(const char *dbspacedirname, int op)
 {
 	DIR		   *dbspace_dir;
 	struct dirent *de;
-	char		rm_path[MAXPGPATH];
+	char		rm_path[MAXPGPATH * 2];
 
 	/* Caller must specify at least one operation. */
 	Assert((op & (UNLOGGED_RELATION_CLEANUP | UNLOGGED_RELATION_INIT)) != 0);
@@ -308,7 +308,7 @@ ResetUnloggedRelationsInDbspaceDir(const char *dbspacedirname, int op)
 			ForkNumber	forkNum;
 			int			oidchars;
 			char		oidbuf[OIDCHARS + 1];
-			char		srcpath[MAXPGPATH];
+			char		srcpath[MAXPGPATH * 2];
 			char		dstpath[MAXPGPATH];
 
 			/* Skip anything that doesn't look like a relation data file. */

src/backend/storage/ipc/dsm.c

@@ -306,9 +306,9 @@ dsm_cleanup_for_mmap(void)
 		if (strncmp(dent->d_name, PG_DYNSHMEM_MMAP_FILE_PREFIX,
 					strlen(PG_DYNSHMEM_MMAP_FILE_PREFIX)) == 0)
 		{
-			char		buf[MAXPGPATH];
+			char		buf[MAXPGPATH + sizeof(PG_DYNSHMEM_DIR)];
 
-			snprintf(buf, MAXPGPATH, PG_DYNSHMEM_DIR "/%s", dent->d_name);
+			snprintf(buf, sizeof(buf), PG_DYNSHMEM_DIR "/%s", dent->d_name);
 
 			elog(DEBUG2, "removing file \"%s\"", buf);
 

src/backend/utils/adt/dbsize.c

@@ -41,7 +41,7 @@ db_dir_size(const char *path)
 	int64		dirsize = 0;
 	struct dirent *direntry;
 	DIR		   *dirdesc;
-	char		filename[MAXPGPATH];
+	char		filename[MAXPGPATH * 2];
 
 	dirdesc = AllocateDir(path);
 
@@ -58,7 +58,7 @@ db_dir_size(const char *path)
 			strcmp(direntry->d_name, "..") == 0)
 			continue;
 
-		snprintf(filename, MAXPGPATH, "%s/%s", path, direntry->d_name);
+		snprintf(filename, sizeof(filename), "%s/%s", path, direntry->d_name);
 
 		if (stat(filename, &fst) < 0)
 		{
@@ -86,7 +86,7 @@ calculate_database_size(Oid dbOid)
 	DIR		   *dirdesc;
 	struct dirent *direntry;
 	char		dirpath[MAXPGPATH];
-	char		pathname[MAXPGPATH];
+	char		pathname[MAXPGPATH + 12 + sizeof(TABLESPACE_VERSION_DIRECTORY)];
 	AclResult	aclresult;
 
 	/* User must have connect privilege for target database */
@@ -98,7 +98,7 @@ calculate_database_size(Oid dbOid)
 	/* Shared storage in pg_global is not counted */
 
 	/* Include pg_default storage */
-	snprintf(pathname, MAXPGPATH, "base/%u", dbOid);
+	snprintf(pathname, sizeof(pathname), "base/%u", dbOid);
 	totalsize = db_dir_size(pathname);
 
 	/* Scan the non-default tablespaces */
@@ -118,7 +118,7 @@ calculate_database_size(Oid dbOid)
 			strcmp(direntry->d_name, "..") == 0)
 			continue;
 
-		snprintf(pathname, MAXPGPATH, "pg_tblspc/%s/%s/%u",
+		snprintf(pathname, sizeof(pathname), "pg_tblspc/%s/%s/%u",
 				 direntry->d_name, TABLESPACE_VERSION_DIRECTORY, dbOid);
 		totalsize += db_dir_size(pathname);
 	}
@@ -166,7 +166,7 @@ static int64
 calculate_tablespace_size(Oid tblspcOid)
 {
 	char		tblspcPath[MAXPGPATH];
-	char		pathname[MAXPGPATH];
+	char		pathname[MAXPGPATH * 2];
 	int64		totalsize = 0;
 	DIR		   *dirdesc;
 	struct dirent *direntry;
@@ -208,7 +208,7 @@ calculate_tablespace_size(Oid tblspcOid)
 			strcmp(direntry->d_name, "..") == 0)
 			continue;
 
-		snprintf(pathname, MAXPGPATH, "%s/%s", tblspcPath, direntry->d_name);
+		snprintf(pathname, sizeof(pathname), "%s/%s", tblspcPath, direntry->d_name);
 
 		if (stat(pathname, &fst) < 0)
 		{

src/backend/utils/cache/relcache.c

@@ -5525,7 +5525,7 @@ RelationCacheInitFileRemove(void)
 	const char *tblspcdir = "pg_tblspc";
 	DIR		   *dir;
 	struct dirent *de;
-	char		path[MAXPGPATH];
+	char		path[MAXPGPATH + 10 + sizeof(TABLESPACE_VERSION_DIRECTORY)];
 
 	/*
 	 * We zap the shared cache file too.  In theory it can't get out of sync
@@ -5567,7 +5567,7 @@ RelationCacheInitFileRemoveInDir(const char *tblspcpath)
 {
 	DIR		   *dir;
 	struct dirent *de;
-	char		initfilename[MAXPGPATH];
+	char		initfilename[MAXPGPATH * 2];
 
 	/* Scan the tablespace directory to find per-database directories */
 	dir = AllocateDir(tblspcpath);

src/backend/utils/error/elog.c

@@ -2228,7 +2228,7 @@ static void
 setup_formatted_log_time(void)
 {
 	pg_time_t	stamp_time;
-	char		msbuf[8];
+	char		msbuf[13];
 
 	if (!saved_timeval_set)
 	{

src/backend/utils/time/snapmgr.c

@@ -1569,7 +1569,7 @@ XactHasExportedSnapshots(void)
 void
 DeleteAllExportedSnapshotFiles(void)
 {
-	char		buf[MAXPGPATH];
+	char		buf[MAXPGPATH + sizeof(SNAPSHOT_EXPORT_DIR)];
 	DIR		   *s_dir;
 	struct dirent *s_de;
 
@@ -1590,7 +1590,7 @@ DeleteAllExportedSnapshotFiles(void)
 			strcmp(s_de->d_name, "..") == 0)
 			continue;
 
-		snprintf(buf, MAXPGPATH, SNAPSHOT_EXPORT_DIR "/%s", s_de->d_name);
+		snprintf(buf, sizeof(buf), SNAPSHOT_EXPORT_DIR "/%s", s_de->d_name);
 		/* Again, unlink failure is not worthy of FATAL */
 		if (unlink(buf))
 			elog(LOG, "could not unlink file \"%s\": %m", buf);