From 2040bb4a0b50ef0434a1a723f00d040ab4f1c06f Mon Sep 17 00:00:00 2001 From: Tom Lane Date: Fri, 14 Apr 2017 17:04:25 -0400 Subject: Clean up manipulations of hash indexes' hasho_flag field. Standardize on testing a hash index page's type by doing (opaque->hasho_flag & LH_PAGE_TYPE) == LH_xxx_PAGE Various places were taking shortcuts like opaque->hasho_flag & LH_BUCKET_PAGE which while not actually wrong, is still bad practice because it encourages use of opaque->hasho_flag & LH_UNUSED_PAGE which *is* wrong (LH_UNUSED_PAGE == 0, so the above is constant false). hash_xlog.c's hash_mask() contained such an incorrect test. This also ensures that we mask out the additional flag bits that hasho_flag has accreted since 9.6. pgstattuple's pgstat_hash_page(), for one, was failing to do that and was thus actively broken. Also fix assorted comments that hadn't been updated to reflect the extended usage of hasho_flag, and fix some macros that were testing just "(hasho_flag & bit)" to use the less dangerous, project-approved form "((hasho_flag & bit) != 0)". Coverity found the bug in hash_mask(); I noted the one in pgstat_hash_page() through code reading. --- contrib/pageinspect/hashfuncs.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-) (limited to 'contrib/pageinspect/hashfuncs.c') diff --git a/contrib/pageinspect/hashfuncs.c b/contrib/pageinspect/hashfuncs.c index dd00aaa81a6..6e52969fd34 100644 --- a/contrib/pageinspect/hashfuncs.c +++ b/contrib/pageinspect/hashfuncs.c @@ -184,7 +184,8 @@ hash_page_type(PG_FUNCTION_ARGS) bytea *raw_page = PG_GETARG_BYTEA_P(0); Page page; HashPageOpaque opaque; - char *type; + int pagetype; + const char *type; if (!superuser()) ereport(ERROR, @@ -200,13 +201,14 @@ hash_page_type(PG_FUNCTION_ARGS) opaque = (HashPageOpaque) PageGetSpecialPointer(page); /* page type (flags) */ - if (opaque->hasho_flag & LH_META_PAGE) + pagetype = opaque->hasho_flag & LH_PAGE_TYPE; + if (pagetype == LH_META_PAGE) type = "metapage"; - else if (opaque->hasho_flag & LH_OVERFLOW_PAGE) + else if (pagetype == LH_OVERFLOW_PAGE) type = "overflow"; - else if (opaque->hasho_flag & LH_BUCKET_PAGE) + else if (pagetype == LH_BUCKET_PAGE) type = "bucket"; - else if (opaque->hasho_flag & LH_BITMAP_PAGE) + else if (pagetype == LH_BITMAP_PAGE) type = "bitmap"; else type = "unused"; -- cgit v1.2.3