From a40598b228e3e67f4e7b4ec9ce9de6dddce33735 Mon Sep 17 00:00:00 2001
From: Panu Matilainen <pmatilai@redhat.com>
Date: Tue, 26 Oct 2010 09:54:55 +0300
Subject: [PATCH] Separate match iterator allocation vs initialization -
 There's exactly one spot within rpm which needs the former behavior   of
 rpmdbInitIterator() on a secondary index with keyp of NULL:  
 rpmFindBaseNamesInDB(): it wants an empty iterator on RPMDBI_BASENAMES,  
 which is then extended as it progresses. Starting with commit  
 c70e076e088589f65160c05ee7cc8db0b3db6d7e, rpmdbInitIterator()   however
 returns the actual index in that case, which is not   optimal for
 rpmFindBaseNamesInDB(). Handle the basenames in db   as the special case it
 is, and have it explicitly create an   empty iterator with the new call.

---
 lib/rpmdb.c          | 59 +++++++++++++++++++++++++++-----------------
 lib/rpmdb_internal.h | 10 ++++++++
 lib/transaction.c    |  2 +-
 3 files changed, 48 insertions(+), 23 deletions(-)

diff --git a/lib/rpmdb.c b/lib/rpmdb.c
index d28109471..ce7c70578 100644
--- a/lib/rpmdb.c
+++ b/lib/rpmdb.c
@@ -2003,6 +2003,42 @@ int rpmdbAppendIterator(rpmdbMatchIterator mi, const int * hdrNums, int nHdrNums
     return 0;
 }
 
+rpmdbMatchIterator rpmdbNewIterator(rpmdb db, rpmDbiTagVal dbitag)
+{
+    rpmdbMatchIterator mi = NULL;
+
+    if (rpmdbOpenIndex(db, dbitag, 0) == NULL)
+	return NULL;
+
+    mi = xcalloc(1, sizeof(*mi));
+    mi->mi_keyp = NULL;
+    mi->mi_keylen = 0;
+    mi->mi_set = NULL;
+    mi->mi_db = rpmdbLink(db);
+    mi->mi_rpmtag = dbitag;
+
+    mi->mi_dbc = NULL;
+    mi->mi_setx = 0;
+    mi->mi_h = NULL;
+    mi->mi_sorted = 0;
+    mi->mi_cflags = 0;
+    mi->mi_modified = 0;
+    mi->mi_prevoffset = 0;
+    mi->mi_offset = 0;
+    mi->mi_filenum = 0;
+    mi->mi_nre = 0;
+    mi->mi_re = NULL;
+
+    mi->mi_ts = NULL;
+    mi->mi_hdrchk = NULL;
+
+    /* Chain cursors for teardown on abnormal exit. */
+    mi->mi_next = rpmmiRock;
+    rpmmiRock = mi;
+
+    return mi;
+};
+
 rpmdbMatchIterator rpmdbInitIterator(rpmdb db, rpmDbiTagVal rpmtag,
 		const void * keyp, size_t keylen)
 {
@@ -2139,31 +2175,10 @@ rpmdbMatchIterator rpmdbInitIterator(rpmdb db, rpmDbiTagVal rpmtag,
 	}
     }
 
-    mi = xcalloc(1, sizeof(*mi));
+    mi = rpmdbNewIterator(db, rpmtag);
     mi->mi_keyp = mi_keyp;
     mi->mi_keylen = keylen;
     mi->mi_set = set;
-    mi->mi_db = rpmdbLink(db);
-    mi->mi_rpmtag = rpmtag;
-
-    /* Chain cursors for teardown on abnormal exit. */
-    mi->mi_next = rpmmiRock;
-    rpmmiRock = mi;
-
-    mi->mi_dbc = NULL;
-    mi->mi_setx = 0;
-    mi->mi_h = NULL;
-    mi->mi_sorted = 0;
-    mi->mi_cflags = 0;
-    mi->mi_modified = 0;
-    mi->mi_prevoffset = 0;
-    mi->mi_offset = 0;
-    mi->mi_filenum = 0;
-    mi->mi_nre = 0;
-    mi->mi_re = NULL;
-
-    mi->mi_ts = NULL;
-    mi->mi_hdrchk = NULL;
 
     if (rpmtag != RPMDBI_PACKAGES && keyp == NULL) {
         rpmdbSortIterator(mi);
diff --git a/lib/rpmdb_internal.h b/lib/rpmdb_internal.h
index 1b691a21a..9447d053a 100644
--- a/lib/rpmdb_internal.h
+++ b/lib/rpmdb_internal.h
@@ -75,6 +75,16 @@ void rpmdbSortIterator(rpmdbMatchIterator mi);
  */
 int rpmdbPruneIterator(rpmdbMatchIterator mi, intHash hdrNums);
 
+/** \ingroup rpmdb
+ * Create a new, empty match iterator (for purposes of extending it
+ * through other means)
+ * @param db		rpm database
+ * @param dbitag	database index tag
+ * @return		empty match iterator
+ */
+RPM_GNUC_INTERNAL
+rpmdbMatchIterator rpmdbNewIterator(rpmdb db, rpmDbiTagVal dbitag);
+
 #ifndef __APPLE__
 /**
  *  * Mergesort, same arguments as qsort(2).
diff --git a/lib/transaction.c b/lib/transaction.c
index ee3f78f67..c7e68493d 100644
--- a/lib/transaction.c
+++ b/lib/transaction.c
@@ -878,7 +878,7 @@ rpmdbMatchIterator rpmFindBaseNamesInDB(rpmts ts, uint64_t fileCount)
     rpmStringSet baseNames = rpmStringSetCreate(fileCount, 
 					hashFunctionString, strcmp, NULL);
 
-    mi = rpmdbInitIterator(rpmtsGetRdb(ts), RPMDBI_BASENAMES, NULL, 0);
+    mi = rpmdbNewIterator(rpmtsGetRdb(ts), RPMDBI_BASENAMES);
 
     pi = rpmtsiInit(ts);
     while ((p = rpmtsiNext(pi, 0)) != NULL) {