7f2f65b61d5546d8a875fc00df6a6d43a9267e25
braney
  Wed Jan 26 11:59:53 2022 -0800
do a null check for database in chromAlias setup

diff --git src/hg/lib/chromAlias.c src/hg/lib/chromAlias.c
index d123ccd..7849260 100644
--- src/hg/lib/chromAlias.c
+++ src/hg/lib/chromAlias.c
@@ -302,30 +302,33 @@
 while ((row = sqlNextRow(sr)) != NULL)
     {
     struct chromAlias *new = chromAliasLoad(row);
     hashAdd(chromHashes.forwardHash, new->alias, new);
     hashAdd(chromHashes.reverseHash, new->chrom, new);
     hashAdd(chromHashes.chromToAliasHash, new->chrom, new->alias);
     hashAdd(chromHashes.aliasToChromHash, new->alias, new->chrom);
     }
 sqlFreeResult(&sr);
 hFreeConn(&conn);
 }
 
 void chromAliasSetup(char *database)
 /* Read in the chromAlias file/table for this database. */
 {
+if (database == NULL)
+    return;
+
 if (!checkDatabase(database))
     return;
 
 if (chromHashes.inited)
     return;
 chromHashes.inited = TRUE;
 
 if (trackHubDatabase(database))
     chromAliasSetupHub(database);
 else
     chromAliasSetupSql(database);
 }
 
 struct hash *chromAliasMakeLookupTable(char *database)
 /* Given a database name and a connection to that database, construct a lookup table