Use sizeof directly instead of defines

We have already done this refactoring for the WAL key code so let's do
it for the SMGR keys too. This makes the code easier to understand.

contrib/pg_tde/src/access/pg_tde_tdemap.c

@@ -41,9 +41,6 @@
 #define PG_TDE_FILEMAGIC			0x03454454	/* version ID value = TDE 03 */
 #define PG_TDE_MAP_FILENAME			"%d_keys"
 
-#define MAP_ENTRY_SIZE			sizeof(TDEMapEntry)
-#define TDE_FILE_HEADER_SIZE	sizeof(TDEFileHeader)
-
 typedef enum
 {
 	MAP_ENTRY_TYPE_EMPTY = 0,
@@ -458,9 +455,9 @@ pg_tde_write_one_map_entry(int fd, const TDEMapEntry *map_entry, off_t *offset,
 {
 	int			bytes_written = 0;
 
-	bytes_written = pg_pwrite(fd, map_entry, MAP_ENTRY_SIZE, *offset);
+	bytes_written = pg_pwrite(fd, map_entry, sizeof(TDEMapEntry), *offset);
 
-	if (bytes_written != MAP_ENTRY_SIZE)
+	if (bytes_written != sizeof(TDEMapEntry))
 	{
 		ereport(ERROR,
 				errcode_for_file_access(),
@@ -719,13 +716,13 @@ pg_tde_file_header_read(const char *tde_filename, int fd, TDEFileHeader *fheader
 {
 	Assert(fheader);
 
-	*bytes_read = pg_pread(fd, fheader, TDE_FILE_HEADER_SIZE, 0);
+	*bytes_read = pg_pread(fd, fheader, sizeof(TDEFileHeader), 0);
 
 	/* File is empty */
 	if (*bytes_read == 0)
 		return;
 
-	if (*bytes_read != TDE_FILE_HEADER_SIZE
+	if (*bytes_read != sizeof(TDEFileHeader)
 		|| fheader->file_version != PG_TDE_FILEMAGIC)
 	{
 		ereport(FATAL,
@@ -747,9 +744,9 @@ pg_tde_file_header_write(const char *tde_filename, int fd, const TDESignedPrinci
 
 	fheader.file_version = PG_TDE_FILEMAGIC;
 	fheader.signed_key_info = *signed_key_info;
-	*bytes_written = pg_pwrite(fd, &fheader, TDE_FILE_HEADER_SIZE, 0);
+	*bytes_written = pg_pwrite(fd, &fheader, sizeof(TDEFileHeader), 0);
 
-	if (*bytes_written != TDE_FILE_HEADER_SIZE)
+	if (*bytes_written != sizeof(TDEFileHeader))
 	{
 		ereport(ERROR,
 				errcode_for_file_access(),
@@ -781,10 +778,10 @@ pg_tde_read_one_map_entry(int map_file, TDEMapEntry *map_entry, off_t *offset)
 	Assert(map_entry);
 	Assert(offset);
 
-	bytes_read = pg_pread(map_file, map_entry, MAP_ENTRY_SIZE, *offset);
+	bytes_read = pg_pread(map_file, map_entry, sizeof(TDEMapEntry), *offset);
 
 	/* We've reached the end of the file. */
-	if (bytes_read != MAP_ENTRY_SIZE)
+	if (bytes_read != sizeof(TDEMapEntry))
 		return false;
 
 	*offset += bytes_read;