pg_dump: Simplify internal archive version handling

The ArchiveHandle structure contained the archive format version number
twice, once as a single field and once split into components.  Simplify
that by just keeping the single field and adding some macros to extract
the components.  Introduce some macros for composing version numbers, to
eliminate the repeated use of magic formulas.  Drop the unused trailing
zero byte from the run-time composite version representation.

reviewed by Tom Lane

1 files changed, 25 insertions, 27 deletions

diff --git a/src/bin/pg_dump/pg_backup_archiver.c b/src/bin/pg_dump/pg_backup_archiver.c
index e237b4a9c90..0e209853509 100644
--- a/src/bin/pg_dump/pg_backup_archiver.c
+++ b/src/bin/pg_dump/pg_backup_archiver.c
@@ -1105,7 +1105,8 @@ PrintTOCSummary(Archive *AHX)
 			fmtName = "UNKNOWN";
 	}
 
-	ahprintf(AH, ";     Dump Version: %d.%d-%d\n", AH->vmaj, AH->vmin, AH->vrev);
+	ahprintf(AH, ";     Dump Version: %d.%d-%d\n",
+			 ARCHIVE_MAJOR(AH->version), ARCHIVE_MINOR(AH->version), ARCHIVE_REV(AH->version));
 	ahprintf(AH, ";     Format: %s\n", fmtName);
 	ahprintf(AH, ";     Integer: %d bytes\n", (int) AH->intSize);
 	ahprintf(AH, ";     Offset: %d bytes\n", (int) AH->offSize);
@@ -2106,6 +2107,7 @@ _discoverArchiveFormat(ArchiveHandle *AH)
 	if (strncmp(sig, "PGDMP", 5) == 0)
 	{
 		int			byteread;
+		char		vmaj, vmin, vrev;
 
 		/*
 		 * Finish reading (most of) a custom-format header.
@@ -2115,31 +2117,30 @@ _discoverArchiveFormat(ArchiveHandle *AH)
 		if ((byteread = fgetc(fh)) == EOF)
 			READ_ERROR_EXIT(fh);
 
-		AH->vmaj = byteread;
+		vmaj = byteread;
 
 		if ((byteread = fgetc(fh)) == EOF)
 			READ_ERROR_EXIT(fh);
 
-		AH->vmin = byteread;
+		vmin = byteread;
 
 		/* Save these too... */
-		AH->lookahead[AH->lookaheadLen++] = AH->vmaj;
-		AH->lookahead[AH->lookaheadLen++] = AH->vmin;
+		AH->lookahead[AH->lookaheadLen++] = vmaj;
+		AH->lookahead[AH->lookaheadLen++] = vmin;
 
 		/* Check header version; varies from V1.0 */
-		if (AH->vmaj > 1 || ((AH->vmaj == 1) && (AH->vmin > 0)))		/* Version > 1.0 */
+		if (vmaj > 1 || (vmaj == 1 && vmin > 0))		/* Version > 1.0 */
 		{
 			if ((byteread = fgetc(fh)) == EOF)
 				READ_ERROR_EXIT(fh);
 
-			AH->vrev = byteread;
-			AH->lookahead[AH->lookaheadLen++] = AH->vrev;
+			vrev = byteread;
+			AH->lookahead[AH->lookaheadLen++] = vrev;
 		}
 		else
-			AH->vrev = 0;
+			vrev = 0;
 
-		/* Make a convenient integer <maj><min><rev>00 */
-		AH->version = ((AH->vmaj * 256 + AH->vmin) * 256 + AH->vrev) * 256 + 0;
+		AH->version = MAKE_ARCHIVE_VERSION(vmaj, vmin, vrev);
 
 		if ((AH->intSize = fgetc(fh)) == EOF)
 			READ_ERROR_EXIT(fh);
@@ -2234,12 +2235,7 @@ _allocAH(const char *FileSpec, const ArchiveFormat fmt,
 
 	/* AH->debugLevel = 100; */
 
-	AH->vmaj = K_VERS_MAJOR;
-	AH->vmin = K_VERS_MINOR;
-	AH->vrev = K_VERS_REV;
-
-	/* Make a convenient integer <maj><min><rev>00 */
-	AH->version = ((AH->vmaj * 256 + AH->vmin) * 256 + AH->vrev) * 256 + 0;
+	AH->version = K_VERS_SELF;
 
 	/* initialize for backwards compatible string processing */
 	AH->public.encoding = 0;	/* PG_SQL_ASCII */
@@ -3528,9 +3524,9 @@ WriteHead(ArchiveHandle *AH)
 	struct tm	crtm;
 
 	(*AH->WriteBufPtr) (AH, "PGDMP", 5);		/* Magic code */
-	(*AH->WriteBytePtr) (AH, AH->vmaj);
-	(*AH->WriteBytePtr) (AH, AH->vmin);
-	(*AH->WriteBytePtr) (AH, AH->vrev);
+	(*AH->WriteBytePtr) (AH, ARCHIVE_MAJOR(AH->version));
+	(*AH->WriteBytePtr) (AH, ARCHIVE_MINOR(AH->version));
+	(*AH->WriteBytePtr) (AH, ARCHIVE_REV(AH->version));
 	(*AH->WriteBytePtr) (AH, AH->intSize);
 	(*AH->WriteBytePtr) (AH, AH->offSize);
 	(*AH->WriteBytePtr) (AH, AH->format);
@@ -3563,24 +3559,26 @@ ReadHead(ArchiveHandle *AH)
 	 */
 	if (!AH->readHeader)
 	{
+		char		vmaj, vmin, vrev;
+
 		(*AH->ReadBufPtr) (AH, tmpMag, 5);
 
 		if (strncmp(tmpMag, "PGDMP", 5) != 0)
 			exit_horribly(modulename, "did not find magic string in file header\n");
 
-		AH->vmaj = (*AH->ReadBytePtr) (AH);
-		AH->vmin = (*AH->ReadBytePtr) (AH);
+		vmaj = (*AH->ReadBytePtr) (AH);
+		vmin = (*AH->ReadBytePtr) (AH);
 
-		if (AH->vmaj > 1 || ((AH->vmaj == 1) && (AH->vmin > 0)))		/* Version > 1.0 */
-			AH->vrev = (*AH->ReadBytePtr) (AH);
+		if (vmaj > 1 || (vmaj == 1 && vmin > 0))		/* Version > 1.0 */
+			vrev = (*AH->ReadBytePtr) (AH);
 		else
-			AH->vrev = 0;
+			vrev = 0;
 
-		AH->version = ((AH->vmaj * 256 + AH->vmin) * 256 + AH->vrev) * 256 + 0;
+		AH->version = MAKE_ARCHIVE_VERSION(vmaj, vmin, vrev);
 
 		if (AH->version < K_VERS_1_0 || AH->version > K_VERS_MAX)
 			exit_horribly(modulename, "unsupported version (%d.%d) in file header\n",
-						  AH->vmaj, AH->vmin);
+						  vmaj, vmin);
 
 		AH->intSize = (*AH->ReadBytePtr) (AH);
 		if (AH->intSize > 32)