ndb: use the generation instead of the current time in blobs

This seems to saner as the somewhat unreliable current time.
This element is not used in normal database operation, it is
for repair tools that need to decide which blob to take if two
blobs have the same pkgid.

lib/backend/ndb/rpmpkg.c

@@ -7,7 +7,6 @@
 #include <sys/file.h>
 #include <fcntl.h>
 #include <stdio.h>
-#include <time.h>
 #include <unistd.h>
 #include <string.h>
 #include <stdlib.h>
@@ -511,7 +510,7 @@ static int rpmpkgValidateZero(rpmpkgdb pkgdb, unsigned int blkoff, unsigned int
 
 /*** Blob primitives ***/
 
-/* head: magic + pkgidx + timestamp + bloblen */
+/* head: magic + pkgidx + generation + bloblen */
 /* tail: adler32 + bloblen + magic */
 
 #define BLOBHEAD_MAGIC	('B' | 'l' << 8 | 'b' << 16 | 'S' << 24)
@@ -520,10 +519,10 @@ static int rpmpkgValidateZero(rpmpkgdb pkgdb, unsigned int blkoff, unsigned int
 #define BLOBHEAD_SIZE	(4 + 4 + 4 + 4)
 #define BLOBTAIL_SIZE	(4 + 4 + 4)
 
-static int rpmpkgReadBlob(rpmpkgdb pkgdb, unsigned int pkgidx, unsigned int blkoff, unsigned int blkcnt, unsigned char *blob, unsigned int *bloblp, unsigned int *tstampp)
+static int rpmpkgReadBlob(rpmpkgdb pkgdb, unsigned int pkgidx, unsigned int blkoff, unsigned int blkcnt, unsigned char *blob, unsigned int *bloblp, unsigned int *generationp)
 {
     unsigned char buf[BLOBHEAD_SIZE > BLOBTAIL_SIZE ? BLOBHEAD_SIZE : BLOBTAIL_SIZE];
-    unsigned int bloblen, toread, tstamp;
+    unsigned int bloblen, toread, generation;
     off_t fileoff;
     unsigned int adl;
     int verifyadler = bloblp ? 0 : 1;
@@ -539,7 +538,7 @@ static int rpmpkgReadBlob(rpmpkgdb pkgdb, unsigned int pkgidx, unsigned int blko
 	return RPMRC_FAIL;	/* bad blob */
     if (le2h(buf + 4) != pkgidx)
 	return RPMRC_FAIL;	/* bad blob */
-    tstamp = le2h(buf + 8);
+    generation = le2h(buf + 8);
     bloblen = le2h(buf + 12);
     if (blkcnt != (BLOBHEAD_SIZE + bloblen + BLOBTAIL_SIZE + BLK_SIZE - 1) / BLK_SIZE)
 	return RPMRC_FAIL;	/* bad blob */
@@ -584,8 +583,8 @@ static int rpmpkgReadBlob(rpmpkgdb pkgdb, unsigned int pkgidx, unsigned int blko
     }
     if (bloblp)
 	*bloblp = bloblen;
-    if (tstampp)
-	*tstampp = tstamp;
+    if (generationp)
+	*generationp = generation;
     return RPMRC_OK;
 }
 
@@ -668,14 +667,14 @@ static int rpmpkgMoveBlob(rpmpkgdb pkgdb, pkgslot *slot, unsigned int newblkoff)
     unsigned int blkoff = slot->blkoff;
     unsigned int blkcnt = slot->blkcnt;
     unsigned char *blob;
-    unsigned int tstamp, blobl;
+    unsigned int generation, blobl;
 
     blob = xmalloc((size_t)blkcnt * BLK_SIZE);
-    if (rpmpkgReadBlob(pkgdb, pkgidx, blkoff, blkcnt, blob, &blobl, &tstamp)) {
+    if (rpmpkgReadBlob(pkgdb, pkgidx, blkoff, blkcnt, blob, &blobl, &generation)) {
 	free(blob);
 	return RPMRC_FAIL;
     }
-    if (rpmpkgWriteBlob(pkgdb, pkgidx, newblkoff, blkcnt, blob, blobl, tstamp)) {
+    if (rpmpkgWriteBlob(pkgdb, pkgidx, newblkoff, blkcnt, blob, blobl, generation)) {
 	free(blob);
 	return RPMRC_FAIL;
     }
@@ -966,7 +965,7 @@ static int rpmpkgPutInternal(rpmpkgdb pkgdb, unsigned int pkgidx, unsigned char
 	return RPMRC_FAIL;
     }
     /* write new blob */
-    if (rpmpkgWriteBlob(pkgdb, pkgidx, blkoff, blkcnt, blob, blobl, (unsigned int)time(0))) {
+    if (rpmpkgWriteBlob(pkgdb, pkgidx, blkoff, blkcnt, blob, blobl, pkgdb->generation)) {
 	return RPMRC_FAIL;
     }
     /* write slot */