fix valgrind warning in pltsql_store_view_definition

[tanscorpio7]

Description

Reset static variable original_query_string back to NULL after use otherwise next queries which do not set original_query_string in ANLTR will read already freed memory.

before this change valgrind reports the following error
Root cause here was calls to sp_describe_first_result_set internally creates a view in tsql dialect but we did not set original query string in anltr, which means it will read old already freed value.

==00:04:42:31.158 8517== VALGRINDERROR-BEGIN
==00:04:42:31.158 8517== Invalid read of size 1
==00:04:42:31.158 8517==    at 0x4C32D82: strlen (vg_replace_strmem.c:494)
==00:04:42:31.158 8517==    by 0xB4D3A4: cstring_to_text (varlena.c:187)
==00:04:42:31.158 8517==    by 0x12A2B8F2: pltsql_store_view_definition (hooks.c:3166)
==00:04:42:31.158 8517==    by 0x728494: DefineView (view.c:517)
==00:04:42:31.158 8517==    by 0x9D21C0: ProcessUtilitySlow (utility.c:1666)
==00:04:42:31.158 8517==    by 0x9D0F95: standard_ProcessUtility (utility.c:1095)
==00:04:42:31.158 8517==    by 0x89EC165: call_next_ProcessUtility (tdsutils.c:756)
==00:04:42:31.158 8517==    by 0x89EC0DC: tdsutils_ProcessUtility (tdsutils.c:731)
==00:04:42:31.158 8517==    by 0x8C0C7B3: pgss_ProcessUtility (pg_stat_statements.c:1202)
==00:04:42:31.158 8517==    by 0x12939404: call_prev_ProcessUtility (pl_handler.c:4196)
==00:04:42:31.158 8517==    by 0x129392CD: bbf_ProcessUtility (pl_handler.c:4168)
==00:04:42:31.158 8517==    by 0x9D00B3: ProcessUtility (utility.c:529)
==00:04:42:31.158 8517==  Address 0x17163480 is 2,208 bytes inside a block of size 8,192 alloc'd
==00:04:42:31.158 8517==    at 0x4C2D065: malloc (vg_replace_malloc.c:381)
==00:04:42:31.158 8517==    by 0xBC25CF: AllocSetContextCreateInternal (aset.c:438)
==00:04:42:31.158 8517==    by 0xB9D50E: hash_create (dynahash.c:385)
==00:04:42:31.159 8517==    by 0x129AA76D: create_compile_context (compile_context.c:25)
==00:04:42:31.159 8517==    by 0x12942D5C: pltsql_compile_inline (pl_comp.c:1035)
==00:04:42:31.159 8517==    by 0x1293C51F: pltsql_inline_handler (pl_handler.c:5253)
==00:04:42:31.159 8517==    by 0x89DEFF5: ExecuteSQLBatch (tdssqlbatch.c:94)
==00:04:42:31.159 8517==    by 0x89DF20C: ProcessSQLBatchRequest (tdssqlbatch.c:142)
==00:04:42:31.159 8517==    by 0x89C943A: ProcessTDSRequest (tdsprotocol.c:392)
==00:04:42:31.159 8517==    by 0x89C9F42: TdsSocketBackend (tdsprotocol.c:636)
==00:04:42:31.159 8517==    by 0x89BDF47: pe_process_command (tds_srv.c:450)
==00:04:42:31.159 8517==    by 0x9CC548: PostgresMain (postgres.c:4729)
==00:04:42:31.159 8517== 
==00:04:42:31.159 8517== VALGRINDERROR-END 

Issues Resolved

[BABEL-5246]

Test Scenarios Covered

test_db_collation-* test cases now run clean with valgrind

Sign Off

Signed-off-by: Tanzeel Khan [email protected]

Check List

• Commits are signed per the DCO using --signoff

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[coveralls]

Pull Request Test Coverage Report for Build 11324827743

Details

• 7 of 9 (77.78%) changed or added relevant lines in 1 file are covered.
• 1 unchanged line in 1 file lost coverage.
• Overall coverage decreased (-0.003%) to 74.485%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
contrib/babelfishpg_tsql/src/pl_exec.c	7	9	77.78%

Files with Coverage Reduction	New Missed Lines	%
contrib/babelfishpg_tds/src/backend/tds/tdsutils.c	1	73.8%

Totals
Change from base Build 11303200995:	-0.003%
Covered Lines:	45153
Relevant Lines:	60620

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💛 - Coveralls