From 573200c188ce825a812ab477c7caa9c0ed851b6a Mon Sep 17 00:00:00 2001
From: Andrew Kane <andrew@ankane.org>
Date: Wed, 7 Dec 2022 15:28:11 -0800
Subject: [PATCH] Use pg_prng_uint32 for Postgres 15

---
 src/ivfbuild.c  |  3 +--
 src/ivfflat.h   | 14 ++++++++++++++
 src/ivfkmeans.c | 13 +------------
 3 files changed, 16 insertions(+), 14 deletions(-)

diff --git a/src/ivfbuild.c b/src/ivfbuild.c
index d8d00c4..408883a 100644
--- a/src/ivfbuild.c
+++ b/src/ivfbuild.c
@@ -5,7 +5,6 @@
 #include "catalog/index.h"
 #include "ivfflat.h"
 #include "miscadmin.h"
-#include "port.h"
 #include "storage/bufmgr.h"
 
 #if PG_VERSION_NUM >= 140000
@@ -108,7 +107,7 @@ SampleRows(IvfflatBuildState * buildstate)
 
 	buildstate->rowstoskip = -1;
 
-	BlockSampler_Init(&buildstate->bs, totalblocks, targsamples, random());
+	BlockSampler_Init(&buildstate->bs, totalblocks, targsamples, RandomInt());
 
 	reservoir_init_selection_state(&buildstate->rstate, targsamples);
 	while (BlockSampler_HasMore(&buildstate->bs))
diff --git a/src/ivfflat.h b/src/ivfflat.h
index a64c28c..5780db8 100644
--- a/src/ivfflat.h
+++ b/src/ivfflat.h
@@ -10,6 +10,12 @@
 #include "utils/tuplesort.h"
 #include "vector.h"
 
+#if PG_VERSION_NUM >= 150000
+#include "common/pg_prng.h"
+#else
+#include "port.h"
+#endif
+
 #ifdef IVFFLAT_BENCH
 #include "portability/instr_time.h"
 #endif
@@ -62,6 +68,14 @@
 #define IvfflatBench(name, code) (code)
 #endif
 
+#if PG_VERSION_NUM >= 150000
+#define RandomDouble() pg_prng_double(&pg_global_prng_state)
+#define RandomInt() pg_prng_uint32(&pg_global_prng_state)
+#else
+#define RandomDouble() (((double) random()) / MAX_RANDOM_VALUE)
+#define RandomInt() random()
+#endif
+
 /* Variables */
 extern int	ivfflat_probes;
 
diff --git a/src/ivfkmeans.c b/src/ivfkmeans.c
index ebb45b1..40d8afc 100644
--- a/src/ivfkmeans.c
+++ b/src/ivfkmeans.c
@@ -4,17 +4,6 @@
 
 #include "ivfflat.h"
 #include "miscadmin.h"
-#include "port.h"
-
-#if PG_VERSION_NUM >= 150000
-#include "common/pg_prng.h"
-#endif
-
-#if PG_VERSION_NUM >= 150000
-#define RandomDouble() pg_prng_double(&pg_global_prng_state)
-#else
-#define RandomDouble() (((double) random()) / MAX_RANDOM_VALUE)
-#endif
 
 /*
  * Initialize with kmeans++
@@ -40,7 +29,7 @@ InitCenters(Relation index, VectorArray samples, VectorArray centers, float *low
 	collation = index->rd_indcollation[0];
 
 	/* Choose an initial center uniformly at random */
-	VectorArraySet(centers, 0, VectorArrayGet(samples, random() % samples->length));
+	VectorArraySet(centers, 0, VectorArrayGet(samples, RandomInt() % samples->length));
 	centers->length++;
 
 	for (j = 0; j < numSamples; j++)