From fc692a02dde02b0c8ddfee56310391731ad7f313 Mon Sep 17 00:00:00 2001
From: Marc Munro <marc@bloodnok.com>
Date: Thu, 12 Nov 2015 16:32:32 -0800
Subject: [PATCH] Fixes for issue raised by Craig Ringer, re use of
 shared_preload_libraries

---
 regress/regress.sh |  8 +++++---
 src/veil_shmem.c   | 10 +++++++---
 2 files changed, 12 insertions(+), 6 deletions(-)

diff --git a/regress/regress.sh b/regress/regress.sh
index 96b094c..867313b 100755
--- a/regress/regress.sh
+++ b/regress/regress.sh
@@ -1162,8 +1162,10 @@ preload_library_message()
     if [ "x$1" = "x1" -o "x$1" = "x2" ]; then
 	echo "
 WARNING: The veil shared library is not defined in shared_preload_libraries 
-(which is defined in postgresql.conf) Without this definition Veil will not run
-"
+(which is defined in postgresql.conf) Without this definition you will be 
+unable to define veil.dbs_in_cluster, veil.shared_hash_elems, and 
+veil.shmem_context_size which will limit the amount of shared memory
+available to veil."
     elif [ "x$1" = "x3" ]; then
 	echo "
 WARNING: The version of veil.so in shared_preload_libraries (defined in
@@ -1233,4 +1235,4 @@ but does not reference an up to date veil shared library." 1>&2
     preload_library_message ${preload_status}
 fi
 
-exit ${STATUS}
\ No newline at end of file
+exit ${STATUS}
diff --git a/src/veil_shmem.c b/src/veil_shmem.c
index 3ae1086..ccefe8b 100644
--- a/src/veil_shmem.c
+++ b/src/veil_shmem.c
@@ -82,14 +82,14 @@ static bool      prepared_for_switch = false;
  * shared memory.  It is initialised in _PG_init() to a lock id that is
  * distinct from any that will be dynamically allocated.
  */
-static LWLockId  VeilLWLock;
+static LWLockId  VeilLWLock = 0;
 
 /**
  * The LWLock to be used while initially setting up shared memory and 
  * allocating a veil database-specific LWLock.  Initialised in
  * _PG_Init()
  */
-static LWLockId  InitialLWLock;
+static LWLockId  InitialLWLock = 0;
 
 /** 
  * Return the index of the other context from the one supplied.
@@ -111,13 +111,14 @@ _PG_init()
 	int veil_dbs;
 
 	/* See definitions of the following two variables, for comments. */
+	fprintf(stderr, "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX\n");
 	VeilLWLock = AddinShmemInitLock;
 	InitialLWLock = AddinShmemInitLock;
 	
 	/* Define GUCs for veil */
 	veil_config_init(); 
 	veil_dbs = veil_dbs_in_cluster();
-
+	
 	/* Request a Veil-specific shared memory context */
 	RequestAddinShmemSpace(2 * veil_shmem_context_size() * veil_dbs);
 
@@ -406,6 +407,9 @@ vl_free(void *mem)
 static void
 shmalloc_init(void)
 {
+	VeilLWLock = AddinShmemInitLock;
+	InitialLWLock = AddinShmemInitLock;
+
 	if (!shared_meminfo) {
 		VarEntry   *var;
 		MemContext *context0;
-- 
2.39.5