Hello,
They are not more nor less relevant than any other "random" constant. The
state needs a default initialization. The point of using DK's is that it
is somehow cannot be some specially crafted value which would have some
special property only know to the purveyor of the constant and could be
used by them to break the algorithm.
Well, none of that is in the comment, which is probably just as well
because it reads like baseless paranoia.
Sure. Welcome to cryptography:-)
*Any* initialization vector should be as good as any other; if it's not,
that's an algorithm fault.
Yep.
(OK, I'll give it a pass for zeroes being bad, but otherwise not.)
Ok. We can use any non-zero constant. What's wrong with constants provided
by a Turing award computer scientist? I find them more attractive that
some stupid 0x0123456789….
* Function names like these convey practically nothing to readers:
+extern int64 pg_prng_i64(pg_prng_state *state); [...]
The intention is obviously "postgres pseudo-random number generator for
<type>". [...]
What would you suggest?
We have names for these types, and those abbreviations are (mostly)
not them. Name-wise I'd be all right with pg_prng_int64 and so on,
Ok. You prefer "uint64" to "u64".
but I still expect that these functions' header comments should be
explicit about uniformity and about the precise output range.
Ok.
As an example, it's far from obvious whether the minimum value
of pg_prng_int32 should be zero or INT_MIN.
(Actually, I suspect you ought to provide both of those cases.)
I agree that it is not obvious. I added "p" for "positive" variants. I
found one place where one could be used.
And the output range of pg_prng_float8 is not merely unobvious, but not
very easy to deduce from examining the code either; not that users
should have to.
Ok.
BTW, why are we bothering with FIRST_BIT_MASK in the first place,
rather than returning "v & 1" for pg_prng_bool?
Because some PRNG are very bad in the low bits, not xoroshiro stuff,
though.
Good, but then you shouldn't write associated code as if that's still
a problem, because you'll cause other people to think it's still a
problem and write equally contorted code elsewhere. "v & 1" is a
transparent way of producing a bool, while this code isn't.
"v & 1" really produces an integer, not a bool. I'd prefer to actually
generate a boolean and let the compiler optimizer do the cleaning.
Some Xoshiro-family generators have "linear artifacts in the low bits",
Although Xoroshiro128** is supposed to be immune, I thought better to keep
away from these, and I could not see why the last bit would be better than
any other bit, so taking the first looked okay to me at least.
I think that the attached v18 addresses most of your concerns.
--
Fabien.
diff --git a/configure b/configure
index 896b781473..f8c8164428 100755
--- a/configure
+++ b/configure
@@ -16463,32 +16463,6 @@ esac
fi
-ac_fn_c_check_func "$LINENO" "random" "ac_cv_func_random"
-if test "x$ac_cv_func_random" = xyes; then :
- $as_echo "#define HAVE_RANDOM 1" >>confdefs.h
-
-else
- case " $LIBOBJS " in
- *" random.$ac_objext "* ) ;;
- *) LIBOBJS="$LIBOBJS random.$ac_objext"
- ;;
-esac
-
-fi
-
-ac_fn_c_check_func "$LINENO" "srandom" "ac_cv_func_srandom"
-if test "x$ac_cv_func_srandom" = xyes; then :
- $as_echo "#define HAVE_SRANDOM 1" >>confdefs.h
-
-else
- case " $LIBOBJS " in
- *" srandom.$ac_objext "* ) ;;
- *) LIBOBJS="$LIBOBJS srandom.$ac_objext"
- ;;
-esac
-
-fi
-
ac_fn_c_check_func "$LINENO" "strlcat" "ac_cv_func_strlcat"
if test "x$ac_cv_func_strlcat" = xyes; then :
$as_echo "#define HAVE_STRLCAT 1" >>confdefs.h
diff --git a/configure.ac b/configure.ac
index b50130b323..a5c10b8d56 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1858,8 +1858,6 @@ AC_REPLACE_FUNCS(m4_normalize([
mkdtemp
pread
pwrite
- random
- srandom
strlcat
strlcpy
strnlen
diff --git a/contrib/amcheck/verify_nbtree.c b/contrib/amcheck/verify_nbtree.c
index 42a830c33b..659ac05655 100644
--- a/contrib/amcheck/verify_nbtree.c
+++ b/contrib/amcheck/verify_nbtree.c
@@ -32,6 +32,7 @@
#include "catalog/index.h"
#include "catalog/pg_am.h"
#include "commands/tablecmds.h"
+#include "common/pg_prng.h"
#include "lib/bloomfilter.h"
#include "miscadmin.h"
#include "storage/lmgr.h"
@@ -466,8 +467,8 @@ bt_check_every_level(Relation rel, Relation heaprel, bool heapkeyspace,
total_pages = RelationGetNumberOfBlocks(rel);
total_elems = Max(total_pages * (MaxTIDsPerBTreePage / 3),
(int64) state->rel->rd_rel->reltuples);
- /* Random seed relies on backend srandom() call to avoid repetition */
- seed = random();
+ /* Random seed relies on backend prng initialization to avoid repetition */
+ seed = pg_prng_uint64(&pg_global_prng_state);
/* Create Bloom filter to fingerprint index */
state->filter = bloom_create(total_elems, maintenance_work_mem, seed);
state->heaptuplespresent = 0;
diff --git a/contrib/auto_explain/auto_explain.c b/contrib/auto_explain/auto_explain.c
index e9092ba359..286d8c5098 100644
--- a/contrib/auto_explain/auto_explain.c
+++ b/contrib/auto_explain/auto_explain.c
@@ -16,6 +16,7 @@
#include "access/parallel.h"
#include "commands/explain.h"
+#include "common/pg_prng.h"
#include "executor/instrument.h"
#include "jit/jit.h"
#include "utils/guc.h"
@@ -275,8 +276,7 @@ explain_ExecutorStart(QueryDesc *queryDesc, int eflags)
if (nesting_level == 0)
{
if (auto_explain_log_min_duration >= 0 && !IsParallelWorker())
- current_query_sampled = (random() < auto_explain_sample_rate *
- ((double) MAX_RANDOM_VALUE + 1));
+ current_query_sampled = pg_prng_double(&pg_global_prng_state) < auto_explain_sample_rate;
else
current_query_sampled = false;
}
diff --git a/contrib/file_fdw/file_fdw.c b/contrib/file_fdw/file_fdw.c
index 2c2f149fb0..146b524076 100644
--- a/contrib/file_fdw/file_fdw.c
+++ b/contrib/file_fdw/file_fdw.c
@@ -1188,7 +1188,7 @@ file_acquire_sample_rows(Relation onerel, int elevel,
* Found a suitable tuple, so save it, replacing one old tuple
* at random
*/
- int k = (int) (targrows * sampler_random_fract(rstate.randstate));
+ int k = (int) (targrows * sampler_random_fract(&rstate.randstate));
Assert(k >= 0 && k < targrows);
heap_freetuple(rows[k]);
diff --git a/contrib/postgres_fdw/postgres_fdw.c b/contrib/postgres_fdw/postgres_fdw.c
index 45a09337d0..f767fdcc6a 100644
--- a/contrib/postgres_fdw/postgres_fdw.c
+++ b/contrib/postgres_fdw/postgres_fdw.c
@@ -5158,7 +5158,7 @@ analyze_row_processor(PGresult *res, int row, PgFdwAnalyzeState *astate)
if (astate->rowstoskip <= 0)
{
/* Choose a random reservoir element to replace. */
- pos = (int) (targrows * sampler_random_fract(astate->rstate.randstate));
+ pos = (int) (targrows * sampler_random_fract(&astate->rstate.randstate));
Assert(pos >= 0 && pos < targrows);
heap_freetuple(astate->rows[pos]);
}
diff --git a/contrib/tablefunc/tablefunc.c b/contrib/tablefunc/tablefunc.c
index 52b272f298..63bb91a646 100644
--- a/contrib/tablefunc/tablefunc.c
+++ b/contrib/tablefunc/tablefunc.c
@@ -36,6 +36,7 @@
#include "access/htup_details.h"
#include "catalog/pg_type.h"
+#include "common/pg_prng.h"
#include "executor/spi.h"
#include "funcapi.h"
#include "lib/stringinfo.h"
@@ -290,8 +291,8 @@ get_normal_pair(float8 *x1, float8 *x2)
do
{
- u1 = (float8) random() / (float8) MAX_RANDOM_VALUE;
- u2 = (float8) random() / (float8) MAX_RANDOM_VALUE;
+ u1 = pg_prng_double(&pg_global_prng_state);
+ u2 = pg_prng_double(&pg_global_prng_state);
v1 = (2.0 * u1) - 1.0;
v2 = (2.0 * u2) - 1.0;
diff --git a/contrib/tsm_system_rows/tsm_system_rows.c b/contrib/tsm_system_rows/tsm_system_rows.c
index 4996612902..1a46d4b143 100644
--- a/contrib/tsm_system_rows/tsm_system_rows.c
+++ b/contrib/tsm_system_rows/tsm_system_rows.c
@@ -69,7 +69,7 @@ static BlockNumber system_rows_nextsampleblock(SampleScanState *node, BlockNumbe
static OffsetNumber system_rows_nextsampletuple(SampleScanState *node,
BlockNumber blockno,
OffsetNumber maxoffset);
-static uint32 random_relative_prime(uint32 n, SamplerRandomState randstate);
+static uint32 random_relative_prime(uint32 n, pg_prng_state *randstate);
/*
@@ -213,25 +213,25 @@ system_rows_nextsampleblock(SampleScanState *node, BlockNumber nblocks)
if (sampler->step == 0)
{
/* Initialize now that we have scan descriptor */
- SamplerRandomState randstate;
+ pg_prng_state randstate;
/* If relation is empty, there's nothing to scan */
if (nblocks == 0)
return InvalidBlockNumber;
/* We only need an RNG during this setup step */
- sampler_random_init_state(sampler->seed, randstate);
+ sampler_random_init_state(sampler->seed, &randstate);
/* Compute nblocks/firstblock/step only once per query */
sampler->nblocks = nblocks;
/* Choose random starting block within the relation */
/* (Actually this is the predecessor of the first block visited) */
- sampler->firstblock = sampler_random_fract(randstate) *
+ sampler->firstblock = sampler_random_fract(&randstate) *
sampler->nblocks;
/* Find relative prime as step size for linear probing */
- sampler->step = random_relative_prime(sampler->nblocks, randstate);
+ sampler->step = random_relative_prime(sampler->nblocks, &randstate);
}
/* Reinitialize lb */
@@ -317,7 +317,7 @@ gcd(uint32 a, uint32 b)
* (else return 1).
*/
static uint32
-random_relative_prime(uint32 n, SamplerRandomState randstate)
+random_relative_prime(uint32 n, pg_prng_state *randstate)
{
uint32 r;
diff --git a/contrib/tsm_system_time/tsm_system_time.c b/contrib/tsm_system_time/tsm_system_time.c
index 788d8f9a68..36acc6c106 100644
--- a/contrib/tsm_system_time/tsm_system_time.c
+++ b/contrib/tsm_system_time/tsm_system_time.c
@@ -69,7 +69,7 @@ static BlockNumber system_time_nextsampleblock(SampleScanState *node, BlockNumbe
static OffsetNumber system_time_nextsampletuple(SampleScanState *node,
BlockNumber blockno,
OffsetNumber maxoffset);
-static uint32 random_relative_prime(uint32 n, SamplerRandomState randstate);
+static uint32 random_relative_prime(uint32 n, pg_prng_state *randstate);
/*
@@ -224,25 +224,25 @@ system_time_nextsampleblock(SampleScanState *node, BlockNumber nblocks)
if (sampler->step == 0)
{
/* Initialize now that we have scan descriptor */
- SamplerRandomState randstate;
+ pg_prng_state randstate;
/* If relation is empty, there's nothing to scan */
if (nblocks == 0)
return InvalidBlockNumber;
/* We only need an RNG during this setup step */
- sampler_random_init_state(sampler->seed, randstate);
+ sampler_random_init_state(sampler->seed, &randstate);
/* Compute nblocks/firstblock/step only once per query */
sampler->nblocks = nblocks;
/* Choose random starting block within the relation */
/* (Actually this is the predecessor of the first block visited) */
- sampler->firstblock = sampler_random_fract(randstate) *
+ sampler->firstblock = sampler_random_fract(&randstate) *
sampler->nblocks;
/* Find relative prime as step size for linear probing */
- sampler->step = random_relative_prime(sampler->nblocks, randstate);
+ sampler->step = random_relative_prime(sampler->nblocks, &randstate);
}
/* Reinitialize lb and start_time */
@@ -330,7 +330,7 @@ gcd(uint32 a, uint32 b)
* (else return 1).
*/
static uint32
-random_relative_prime(uint32 n, SamplerRandomState randstate)
+random_relative_prime(uint32 n, pg_prng_state *randstate)
{
uint32 r;
diff --git a/src/backend/access/gin/ginget.c b/src/backend/access/gin/ginget.c
index 03191e016c..e93bf29999 100644
--- a/src/backend/access/gin/ginget.c
+++ b/src/backend/access/gin/ginget.c
@@ -16,6 +16,7 @@
#include "access/gin_private.h"
#include "access/relscan.h"
+#include "common/pg_prng.h"
#include "miscadmin.h"
#include "storage/predicate.h"
#include "utils/datum.h"
@@ -787,7 +788,7 @@ entryLoadMoreItems(GinState *ginstate, GinScanEntry entry,
}
}
-#define gin_rand() (((double) random()) / ((double) MAX_RANDOM_VALUE))
+#define gin_rand() pg_prng_double(&pg_global_prng_state)
#define dropItem(e) ( gin_rand() > ((double)GinFuzzySearchLimit)/((double)((e)->predictNumberResult)) )
/*
diff --git a/src/backend/access/gist/gistutil.c b/src/backend/access/gist/gistutil.c
index 43ba03b6eb..94dbabc198 100644
--- a/src/backend/access/gist/gistutil.c
+++ b/src/backend/access/gist/gistutil.c
@@ -19,6 +19,7 @@
#include "access/htup_details.h"
#include "access/reloptions.h"
#include "catalog/pg_opclass.h"
+#include "common/pg_prng.h"
#include "storage/indexfsm.h"
#include "storage/lmgr.h"
#include "utils/float.h"
@@ -507,7 +508,7 @@ gistchoose(Relation r, Page p, IndexTuple it, /* it has compressed entry */
if (keep_current_best == -1)
{
/* we didn't make the random choice yet for this old best */
- keep_current_best = (random() <= (MAX_RANDOM_VALUE / 2)) ? 1 : 0;
+ keep_current_best = pg_prng_bool(&pg_global_prng_state) ? 1 : 0;
}
if (keep_current_best == 0)
{
@@ -529,7 +530,7 @@ gistchoose(Relation r, Page p, IndexTuple it, /* it has compressed entry */
if (keep_current_best == -1)
{
/* we didn't make the random choice yet for this old best */
- keep_current_best = (random() <= (MAX_RANDOM_VALUE / 2)) ? 1 : 0;
+ keep_current_best = pg_prng_bool(&pg_global_prng_state) ? 1 : 0;
}
if (keep_current_best == 1)
break;
diff --git a/src/backend/access/nbtree/nbtinsert.c b/src/backend/access/nbtree/nbtinsert.c
index 0fe8c70939..2b898d312c 100644
--- a/src/backend/access/nbtree/nbtinsert.c
+++ b/src/backend/access/nbtree/nbtinsert.c
@@ -19,6 +19,7 @@
#include "access/nbtxlog.h"
#include "access/transam.h"
#include "access/xloginsert.h"
+#include "common/pg_prng.h"
#include "lib/qunique.h"
#include "miscadmin.h"
#include "storage/lmgr.h"
@@ -965,7 +966,7 @@ _bt_findinsertloc(Relation rel,
if (P_RIGHTMOST(opaque) ||
_bt_compare(rel, itup_key, page, P_HIKEY) != 0 ||
- random() <= (MAX_RANDOM_VALUE / 100))
+ pg_prng_double(&pg_global_prng_state) <= 0.01)
break;
_bt_stepright(rel, insertstate, stack);
diff --git a/src/backend/access/spgist/spgdoinsert.c b/src/backend/access/spgist/spgdoinsert.c
index 70557bcf3d..70dd86b19a 100644
--- a/src/backend/access/spgist/spgdoinsert.c
+++ b/src/backend/access/spgist/spgdoinsert.c
@@ -19,6 +19,7 @@
#include "access/spgist_private.h"
#include "access/spgxlog.h"
#include "access/xloginsert.h"
+#include "common/pg_prng.h"
#include "miscadmin.h"
#include "storage/bufmgr.h"
#include "utils/rel.h"
@@ -2210,7 +2211,7 @@ spgdoinsert(Relation index, SpGistState *state,
if (out.resultType == spgAddNode)
elog(ERROR, "cannot add a node to an allTheSame inner tuple");
else if (out.resultType == spgMatchNode)
- out.result.matchNode.nodeN = random() % innerTuple->nNodes;
+ out.result.matchNode.nodeN = pg_prng_uint32(&pg_global_prng_state) % innerTuple->nNodes;
}
switch (out.resultType)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 8e35c432f5..e7b0bc804d 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -37,6 +37,7 @@
#include "commands/async.h"
#include "commands/tablecmds.h"
#include "commands/trigger.h"
+#include "common/pg_prng.h"
#include "executor/spi.h"
#include "libpq/be-fsstubs.h"
#include "libpq/pqsignal.h"
@@ -1990,7 +1991,7 @@ StartTransaction(void)
/* Determine if statements are logged in this transaction */
xact_is_sampled = log_xact_sample_rate != 0 &&
(log_xact_sample_rate == 1 ||
- random() <= log_xact_sample_rate * MAX_RANDOM_VALUE);
+ pg_prng_double(&pg_global_prng_state) <= log_xact_sample_rate);
/*
* initialize current transaction state fields
diff --git a/src/backend/commands/analyze.c b/src/backend/commands/analyze.c
index 4928702aec..af96a914f7 100644
--- a/src/backend/commands/analyze.c
+++ b/src/backend/commands/analyze.c
@@ -38,6 +38,7 @@
#include "commands/progress.h"
#include "commands/tablecmds.h"
#include "commands/vacuum.h"
+#include "common/pg_prng.h"
#include "executor/executor.h"
#include "foreign/fdwapi.h"
#include "miscadmin.h"
@@ -1162,7 +1163,7 @@ acquire_sample_rows(Relation onerel, int elevel,
OldestXmin = GetOldestNonRemovableTransactionId(onerel);
/* Prepare for sampling block numbers */
- randseed = random();
+ randseed = pg_prng_int32(&pg_global_prng_state);
nblocks = BlockSampler_Init(&bs, totalblocks, targrows, randseed);
#ifdef USE_PREFETCH
@@ -1279,7 +1280,7 @@ acquire_sample_rows(Relation onerel, int elevel,
* Found a suitable tuple, so save it, replacing one old
* tuple at random
*/
- int k = (int) (targrows * sampler_random_fract(rstate.randstate));
+ int k = (int) (targrows * sampler_random_fract(&rstate.randstate));
Assert(k >= 0 && k < targrows);
heap_freetuple(rows[k]);
diff --git a/src/backend/executor/nodeSamplescan.c b/src/backend/executor/nodeSamplescan.c
index 44232d50d0..20f4e1f119 100644
--- a/src/backend/executor/nodeSamplescan.c
+++ b/src/backend/executor/nodeSamplescan.c
@@ -17,6 +17,7 @@
#include "access/relscan.h"
#include "access/tableam.h"
#include "access/tsmapi.h"
+#include "common/pg_prng.h"
#include "executor/executor.h"
#include "executor/nodeSamplescan.h"
#include "miscadmin.h"
@@ -154,7 +155,7 @@ ExecInitSampleScan(SampleScan *node, EState *estate, int eflags)
* do this just once, since the seed shouldn't change over rescans.
*/
if (tsc->repeatable == NULL)
- scanstate->seed = random();
+ scanstate->seed = pg_prng_int32(&pg_global_prng_state);
/*
* Finally, initialize the TABLESAMPLE method handler.
diff --git a/src/backend/optimizer/geqo/geqo_random.c b/src/backend/optimizer/geqo/geqo_random.c
index f21bc047e6..776fce495d 100644
--- a/src/backend/optimizer/geqo/geqo_random.c
+++ b/src/backend/optimizer/geqo/geqo_random.c
@@ -21,14 +21,7 @@ geqo_set_seed(PlannerInfo *root, double seed)
{
GeqoPrivateData *private = (GeqoPrivateData *) root->join_search_private;
- /*
- * XXX. This seeding algorithm could certainly be improved - but it is not
- * critical to do so.
- */
- memset(private->random_state, 0, sizeof(private->random_state));
- memcpy(private->random_state,
- &seed,
- Min(sizeof(private->random_state), sizeof(seed)));
+ pg_prng_fseed(&private->random_state, seed);
}
double
@@ -36,5 +29,5 @@ geqo_rand(PlannerInfo *root)
{
GeqoPrivateData *private = (GeqoPrivateData *) root->join_search_private;
- return pg_erand48(private->random_state);
+ return pg_prng_double(&private->random_state);
}
diff --git a/src/backend/postmaster/postmaster.c b/src/backend/postmaster/postmaster.c
index db797c040b..5d68257bb5 100644
--- a/src/backend/postmaster/postmaster.c
+++ b/src/backend/postmaster/postmaster.c
@@ -98,6 +98,7 @@
#include "catalog/pg_control.h"
#include "common/file_perm.h"
#include "common/ip.h"
+#include "common/pg_prng.h"
#include "common/string.h"
#include "lib/ilist.h"
#include "libpq/auth.h"
@@ -2699,19 +2700,22 @@ ClosePostmasterPorts(bool am_syslogger)
void
InitProcessGlobals(void)
{
- unsigned int rseed;
-
MyProcPid = getpid();
MyStartTimestamp = GetCurrentTimestamp();
MyStartTime = timestamptz_to_time_t(MyStartTimestamp);
/*
- * Set a different seed for random() in every process. We want something
+ * Set a different global seed in every process. We want something
* unpredictable, so if possible, use high-quality random bits for the
* seed. Otherwise, fall back to a seed based on timestamp and PID.
*/
- if (!pg_strong_random(&rseed, sizeof(rseed)))
+ if (unlikely(!pg_prng_strong_seed(&pg_global_prng_state)))
{
+ uint64 rseed;
+
+ ereport(WARNING,
+ (errmsg_internal("pg_prng_strong_seed() failed, falling back to weaker seeding")));
+
/*
* Since PIDs and timestamps tend to change more frequently in their
* least significant bits, shift the timestamp left to allow a larger
@@ -2722,8 +2726,14 @@ InitProcessGlobals(void)
rseed = ((uint64) MyProcPid) ^
((uint64) MyStartTimestamp << 12) ^
((uint64) MyStartTimestamp >> 20);
+
+ pg_prng_seed(&pg_global_prng_state, rseed);
}
- srandom(rseed);
+
+#ifndef WIN32
+ /* random() should not be used anywhere, but just in case */
+ srandom(pg_prng_int32(&pg_global_prng_state));
+#endif
}
diff --git a/src/backend/storage/file/fd.c b/src/backend/storage/file/fd.c
index cb1a8dd34f..463b119d6c 100644
--- a/src/backend/storage/file/fd.c
+++ b/src/backend/storage/file/fd.c
@@ -92,6 +92,7 @@
#include "catalog/pg_tablespace.h"
#include "common/file_perm.h"
#include "common/file_utils.h"
+#include "common/pg_prng.h"
#include "miscadmin.h"
#include "pgstat.h"
#include "port/pg_iovec.h"
@@ -2939,7 +2940,7 @@ SetTempTablespaces(Oid *tableSpaces, int numSpaces)
* available tablespaces.
*/
if (numSpaces > 1)
- nextTempTableSpace = random() % numSpaces;
+ nextTempTableSpace = pg_prng_uint32(&pg_global_prng_state) % numSpaces;
else
nextTempTableSpace = 0;
}
diff --git a/src/backend/storage/ipc/dsm.c b/src/backend/storage/ipc/dsm.c
index b461a5f7e9..cfb10e9f3e 100644
--- a/src/backend/storage/ipc/dsm.c
+++ b/src/backend/storage/ipc/dsm.c
@@ -33,6 +33,7 @@
#endif
#include <sys/stat.h>
+#include "common/pg_prng.h"
#include "lib/ilist.h"
#include "miscadmin.h"
#include "port/pg_bitutils.h"
@@ -180,7 +181,7 @@ dsm_postmaster_startup(PGShmemHeader *shim)
{
Assert(dsm_control_address == NULL);
Assert(dsm_control_mapped_size == 0);
- dsm_control_handle = random() << 1; /* Even numbers only */
+ dsm_control_handle = pg_prng_uint32(&pg_global_prng_state) << 1; /* Even numbers only */
if (dsm_control_handle == DSM_HANDLE_INVALID)
continue;
if (dsm_impl_op(DSM_OP_CREATE, dsm_control_handle, segsize,
@@ -536,7 +537,7 @@ dsm_create(Size size, int flags)
for (;;)
{
Assert(seg->mapped_address == NULL && seg->mapped_size == 0);
- seg->handle = random() << 1; /* Even numbers only */
+ seg->handle = pg_prng_uint32(&pg_global_prng_state) << 1; /* Even numbers only */
if (seg->handle == DSM_HANDLE_INVALID) /* Reserve sentinel */
continue;
if (dsm_impl_op(DSM_OP_CREATE, seg->handle, size, &seg->impl_private,
@@ -1237,7 +1238,7 @@ make_main_region_dsm_handle(int slot)
*/
handle = 1;
handle |= slot << 1;
- handle |= random() << (pg_leftmost_one_pos32(dsm_control->maxitems) + 1);
+ handle |= pg_prng_int32(&pg_global_prng_state) << (pg_leftmost_one_pos32(dsm_control->maxitems) + 1);
return handle;
}
diff --git a/src/backend/storage/lmgr/s_lock.c b/src/backend/storage/lmgr/s_lock.c
index 91322a40c1..2f0ed6fd9e 100644
--- a/src/backend/storage/lmgr/s_lock.c
+++ b/src/backend/storage/lmgr/s_lock.c
@@ -50,6 +50,7 @@
#include <time.h>
#include <unistd.h>
+#include "common/pg_prng.h"
#include "port/atomics.h"
#include "storage/s_lock.h"
@@ -63,6 +64,7 @@
slock_t dummy_spinlock;
static int spins_per_delay = DEFAULT_SPINS_PER_DELAY;
+static pg_prng_state prng_state;
/*
@@ -143,8 +145,7 @@ perform_spin_delay(SpinDelayStatus *status)
#endif
/* increase delay by a random fraction between 1X and 2X */
- status->cur_delay += (int) (status->cur_delay *
- ((double) random() / (double) MAX_RANDOM_VALUE) + 0.5);
+ status->cur_delay += (int) (status->cur_delay * (pg_prng_double(&prng_state) + 0.5));
/* wrap back to minimum delay when max is exceeded */
if (status->cur_delay > MAX_DELAY_USEC)
status->cur_delay = MIN_DELAY_USEC;
@@ -303,7 +304,7 @@ volatile struct test_lock_struct test_lock;
int
main()
{
- srandom((unsigned int) time(NULL));
+ pg_prng_seed(&prng_state, (unsigned int) time(NULL));
test_lock.pad1 = test_lock.pad2 = 0x44;
diff --git a/src/backend/tcop/postgres.c b/src/backend/tcop/postgres.c
index 0775abe35d..902d4e7ff8 100644
--- a/src/backend/tcop/postgres.c
+++ b/src/backend/tcop/postgres.c
@@ -42,6 +42,7 @@
#include "catalog/pg_type.h"
#include "commands/async.h"
#include "commands/prepare.h"
+#include "common/pg_prng.h"
#include "executor/spi.h"
#include "jit/jit.h"
#include "libpq/libpq.h"
@@ -2355,13 +2356,13 @@ check_log_duration(char *msec_str, bool was_logged)
/*
* Do not log if log_statement_sample_rate = 0. Log a sample if
- * log_statement_sample_rate <= 1 and avoid unnecessary random() call
+ * log_statement_sample_rate <= 1 and avoid unnecessary random call
* if log_statement_sample_rate = 1.
*/
if (exceeded_sample_duration)
in_sample = log_statement_sample_rate != 0 &&
(log_statement_sample_rate == 1 ||
- random() <= log_statement_sample_rate * MAX_RANDOM_VALUE);
+ pg_prng_double(&pg_global_prng_state) <= log_statement_sample_rate);
if (exceeded_duration || in_sample || log_duration || xact_is_sampled)
{
diff --git a/src/backend/utils/adt/float.c b/src/backend/utils/adt/float.c
index 098bbb372b..1af6fdaf14 100644
--- a/src/backend/utils/adt/float.c
+++ b/src/backend/utils/adt/float.c
@@ -21,6 +21,7 @@
#include "catalog/pg_type.h"
#include "common/int.h"
+#include "common/pg_prng.h"
#include "common/shortest_dec.h"
#include "libpq/pqformat.h"
#include "miscadmin.h"
@@ -65,7 +66,7 @@ float8 degree_c_one = 1.0;
/* State for drandom() and setseed() */
static bool drandom_seed_set = false;
-static unsigned short drandom_seed[3] = {0, 0, 0};
+static pg_prng_state drandom_seed = PG_PRNG_DEFAULT_STATE;
/* Local function prototypes */
static double sind_q1(double x);
@@ -2762,22 +2763,20 @@ drandom(PG_FUNCTION_ARGS)
* Should that fail for some reason, we fall back on a lower-quality
* seed based on current time and PID.
*/
- if (!pg_strong_random(drandom_seed, sizeof(drandom_seed)))
+ if (!pg_strong_random(&drandom_seed, sizeof(drandom_seed)))
{
TimestampTz now = GetCurrentTimestamp();
uint64 iseed;
/* Mix the PID with the most predictable bits of the timestamp */
iseed = (uint64) now ^ ((uint64) MyProcPid << 32);
- drandom_seed[0] = (unsigned short) iseed;
- drandom_seed[1] = (unsigned short) (iseed >> 16);
- drandom_seed[2] = (unsigned short) (iseed >> 32);
+ pg_prng_seed(&drandom_seed, iseed);
}
drandom_seed_set = true;
}
- /* pg_erand48 produces desired result range [0.0 - 1.0) */
- result = pg_erand48(drandom_seed);
+ /* produces desired result range [0.0 - 1.0) */
+ result = pg_prng_double(&drandom_seed);
PG_RETURN_FLOAT8(result);
}
@@ -2790,7 +2789,6 @@ Datum
setseed(PG_FUNCTION_ARGS)
{
float8 seed = PG_GETARG_FLOAT8(0);
- uint64 iseed;
if (seed < -1 || seed > 1 || isnan(seed))
ereport(ERROR,
@@ -2798,11 +2796,7 @@ setseed(PG_FUNCTION_ARGS)
errmsg("setseed parameter %g is out of allowed range [-1,1]",
seed)));
- /* Use sign bit + 47 fractional bits to fill drandom_seed[] */
- iseed = (int64) (seed * (float8) UINT64CONST(0x7FFFFFFFFFFF));
- drandom_seed[0] = (unsigned short) iseed;
- drandom_seed[1] = (unsigned short) (iseed >> 16);
- drandom_seed[2] = (unsigned short) (iseed >> 32);
+ pg_prng_fseed(&drandom_seed, seed);
drandom_seed_set = true;
PG_RETURN_VOID();
diff --git a/src/backend/utils/misc/sampling.c b/src/backend/utils/misc/sampling.c
index 0c327e823f..4dd3463441 100644
--- a/src/backend/utils/misc/sampling.c
+++ b/src/backend/utils/misc/sampling.c
@@ -49,7 +49,7 @@ BlockSampler_Init(BlockSampler bs, BlockNumber nblocks, int samplesize,
bs->t = 0; /* blocks scanned so far */
bs->m = 0; /* blocks selected so far */
- sampler_random_init_state(randseed, bs->randstate);
+ sampler_random_init_state(randseed, &bs->randstate);
return Min(bs->n, bs->N);
}
@@ -98,7 +98,7 @@ BlockSampler_Next(BlockSampler bs)
* less than k, which means that we cannot fail to select enough blocks.
*----------
*/
- V = sampler_random_fract(bs->randstate);
+ V = sampler_random_fract(&bs->randstate);
p = 1.0 - (double) k / (double) K;
while (V < p)
{
@@ -136,10 +136,10 @@ reservoir_init_selection_state(ReservoirState rs, int n)
* Reservoir sampling is not used anywhere where it would need to return
* repeatable results so we can initialize it randomly.
*/
- sampler_random_init_state(random(), rs->randstate);
+ sampler_random_init_state(pg_prng_uint32(&pg_global_prng_state), &rs->randstate);
/* Initial value of W (for use when Algorithm Z is first applied) */
- rs->W = exp(-log(sampler_random_fract(rs->randstate)) / n);
+ rs->W = exp(-log(sampler_random_fract(&rs->randstate)) / n);
}
double
@@ -154,7 +154,7 @@ reservoir_get_next_S(ReservoirState rs, double t, int n)
double V,
quot;
- V = sampler_random_fract(rs->randstate); /* Generate V */
+ V = sampler_random_fract(&rs->randstate); /* Generate V */
S = 0;
t += 1;
/* Note: "num" in Vitter's code is always equal to t - n */
@@ -186,7 +186,7 @@ reservoir_get_next_S(ReservoirState rs, double t, int n)
tmp;
/* Generate U and X */
- U = sampler_random_fract(rs->randstate);
+ U = sampler_random_fract(&rs->randstate);
X = t * (W - 1.0);
S = floor(X); /* S is tentatively set to floor(X) */
/* Test if U <= h(S)/cg(X) in the manner of (6.3) */
@@ -215,7 +215,7 @@ reservoir_get_next_S(ReservoirState rs, double t, int n)
y *= numer / denom;
denom -= 1;
}
- W = exp(-log(sampler_random_fract(rs->randstate)) / n); /* Generate W in advance */
+ W = exp(-log(sampler_random_fract(&rs->randstate)) / n); /* Generate W in advance */
if (exp(log(y) / n) <= (t + X) / t)
break;
}
@@ -230,24 +230,22 @@ reservoir_get_next_S(ReservoirState rs, double t, int n)
*----------
*/
void
-sampler_random_init_state(long seed, SamplerRandomState randstate)
+sampler_random_init_state(long seed, pg_prng_state *randstate)
{
- randstate[0] = 0x330e; /* same as pg_erand48, but could be anything */
- randstate[1] = (unsigned short) seed;
- randstate[2] = (unsigned short) (seed >> 16);
+ pg_prng_seed(randstate, (uint64_t) seed);
}
/* Select a random value R uniformly distributed in (0 - 1) */
double
-sampler_random_fract(SamplerRandomState randstate)
+sampler_random_fract(pg_prng_state *randstate)
{
double res;
- /* pg_erand48 returns a value in [0.0 - 1.0), so we must reject 0 */
+ /* pg_prng_double returned value in [0.0 - 1.0), so we must reject 0.0 */
do
{
- res = pg_erand48(randstate);
- } while (res == 0.0);
+ res = pg_prng_double(randstate);
+ } while (unlikely(res == 0.0));
return res;
}
@@ -266,22 +264,28 @@ double
anl_random_fract(void)
{
/* initialize if first time through */
- if (oldrs.randstate[0] == 0)
- sampler_random_init_state(random(), oldrs.randstate);
+ if (!oldrs.randstate_initialized)
+ {
+ sampler_random_init_state(pg_prng_uint32(&pg_global_prng_state), &oldrs.randstate);
+ oldrs.randstate_initialized = true;
+ }
/* and compute a random fraction */
- return sampler_random_fract(oldrs.randstate);
+ return sampler_random_fract(&oldrs.randstate);
}
double
anl_init_selection_state(int n)
{
/* initialize if first time through */
- if (oldrs.randstate[0] == 0)
- sampler_random_init_state(random(), oldrs.randstate);
+ if (!oldrs.randstate_initialized)
+ {
+ sampler_random_init_state(pg_prng_uint32(&pg_global_prng_state), &oldrs.randstate);
+ oldrs.randstate_initialized = true;
+ }
/* Initial value of W (for use when Algorithm Z is first applied) */
- return exp(-log(sampler_random_fract(oldrs.randstate)) / n);
+ return exp(-log(sampler_random_fract(&oldrs.randstate)) / n);
}
double
diff --git a/src/bin/initdb/initdb.c b/src/bin/initdb/initdb.c
index 3c61c789e4..78ccb0944c 100644
--- a/src/bin/initdb/initdb.c
+++ b/src/bin/initdb/initdb.c
@@ -66,6 +66,7 @@
#include "common/file_perm.h"
#include "common/file_utils.h"
#include "common/logging.h"
+#include "common/pg_prng.h"
#include "common/restricted_token.h"
#include "common/string.h"
#include "common/username.h"
@@ -880,9 +881,10 @@ choose_dsm_implementation(void)
{
#ifdef HAVE_SHM_OPEN
int ntries = 10;
+ pg_prng_state prng_state;
- /* Initialize random(); this function is its only user in this program. */
- srandom((unsigned int) (getpid() ^ time(NULL)));
+ /* Initialize pgng state this function is its only user in this program. */
+ pg_prng_seed(&prng_state, ((unsigned int) (getpid() ^ time(NULL))));
while (ntries > 0)
{
@@ -890,7 +892,7 @@ choose_dsm_implementation(void)
char name[64];
int fd;
- handle = random();
+ handle = pg_prng_uint32(&prng_state);
snprintf(name, 64, "/PostgreSQL.%u", handle);
if ((fd = shm_open(name, O_CREAT | O_RDWR | O_EXCL, 0600)) != -1)
{
diff --git a/src/bin/pg_test_fsync/pg_test_fsync.c b/src/bin/pg_test_fsync/pg_test_fsync.c
index fef31844fa..422070c487 100644
--- a/src/bin/pg_test_fsync/pg_test_fsync.c
+++ b/src/bin/pg_test_fsync/pg_test_fsync.c
@@ -15,6 +15,7 @@
#include "access/xlogdefs.h"
#include "common/logging.h"
+#include "common/pg_prng.h"
#include "getopt_long.h"
/*
@@ -71,6 +72,7 @@ static char full_buf[DEFAULT_XLOG_SEG_SIZE],
static struct timeval start_t,
stop_t;
static bool alarm_triggered = false;
+static pg_prng_state prng_state;
static void handle_args(int argc, char *argv[]);
@@ -117,6 +119,12 @@ main(int argc, char *argv[])
pqsignal(SIGHUP, signal_cleanup);
#endif
+ if(unlikely(!pg_prng_strong_seed(&prng_state)))
+ {
+ pg_log_error("pg_prng_strong_seed() failed");
+ exit(1);
+ }
+
prepare_buf();
test_open();
@@ -233,7 +241,7 @@ prepare_buf(void)
/* write random data into buffer */
for (ops = 0; ops < DEFAULT_XLOG_SEG_SIZE; ops++)
- full_buf[ops] = random();
+ full_buf[ops] = pg_prng_uint32(&prng_state);
buf = (char *) TYPEALIGN(XLOG_BLCKSZ, full_buf);
}
diff --git a/src/bin/pgbench/pgbench.c b/src/bin/pgbench/pgbench.c
index c12b6f0615..6b91c5b11e 100644
--- a/src/bin/pgbench/pgbench.c
+++ b/src/bin/pgbench/pgbench.c
@@ -58,6 +58,7 @@
#endif
#include "common/int.h"
+#include "common/pg_prng.h"
#include "common/logging.h"
#include "common/string.h"
#include "common/username.h"
@@ -350,16 +351,8 @@ typedef struct StatsData
*/
pg_time_usec_t epoch_shift;
-/*
- * Struct to keep random state.
- */
-typedef struct RandomState
-{
- unsigned short xseed[3];
-} RandomState;
-
/* Various random sequences are initialized from this one. */
-static RandomState base_random_sequence;
+static pg_prng_state base_random_sequence;
/* Synchronization barrier for start and connection */
static THREAD_BARRIER_T barrier;
@@ -461,7 +454,7 @@ typedef struct
* Separate randomness for each client. This is used for random functions
* PGBENCH_RANDOM_* during the execution of the script.
*/
- RandomState cs_func_rs;
+ pg_prng_state cs_func_rs;
int use_file; /* index in sql_script for this client */
int command; /* command number in script */
@@ -498,9 +491,9 @@ typedef struct
* random state to make all of them independent of each other and
* therefore deterministic at the thread level.
*/
- RandomState ts_choose_rs; /* random state for selecting a script */
- RandomState ts_throttle_rs; /* random state for transaction throttling */
- RandomState ts_sample_rs; /* random state for log sampling */
+ pg_prng_state ts_choose_rs; /* random state for selecting a script */
+ pg_prng_state ts_throttle_rs; /* random state for transaction throttling */
+ pg_prng_state ts_sample_rs; /* random state for log sampling */
int64 throttle_trigger; /* previous/next throttling (us) */
FILE *logfile; /* where to log, or NULL */
@@ -898,42 +891,28 @@ strtodouble(const char *str, bool errorOK, double *dv)
}
/*
- * Initialize a random state struct.
+ * Initialize a prng state struct.
*
* We derive the seed from base_random_sequence, which must be set up already.
*/
static void
-initRandomState(RandomState *random_state)
+initRandomState(pg_prng_state *state)
{
- random_state->xseed[0] = (unsigned short)
- (pg_jrand48(base_random_sequence.xseed) & 0xFFFF);
- random_state->xseed[1] = (unsigned short)
- (pg_jrand48(base_random_sequence.xseed) & 0xFFFF);
- random_state->xseed[2] = (unsigned short)
- (pg_jrand48(base_random_sequence.xseed) & 0xFFFF);
+ pg_prng_seed(state, pg_prng_uint64(&base_random_sequence));
}
+
/*
- * Random number generator: uniform distribution from min to max inclusive.
+ * PRNG: uniform distribution from min to max inclusive.
*
* Although the limits are expressed as int64, you can't generate the full
* int64 range in one call, because the difference of the limits mustn't
- * overflow int64. In practice it's unwise to ask for more than an int32
- * range, because of the limited precision of pg_erand48().
+ * overflow int64. This is not checked.
*/
static int64
-getrand(RandomState *random_state, int64 min, int64 max)
+getrand(pg_prng_state *state, int64 min, int64 max)
{
- /*
- * Odd coding is so that min and max have approximately the same chance of
- * being selected as do numbers between them.
- *
- * pg_erand48() is thread-safe and concurrent, which is why we use it
- * rather than random(), which in glibc is non-reentrant, and therefore
- * protected by a mutex, and therefore a bottleneck on machines with many
- * CPUs.
- */
- return min + (int64) ((max - min + 1) * pg_erand48(random_state->xseed));
+ return min + (int64) pg_prng_uint64_range(state, 0, max - min);
}
/*
@@ -942,8 +921,7 @@ getrand(RandomState *random_state, int64 min, int64 max)
* value is exp(-parameter).
*/
static int64
-getExponentialRand(RandomState *random_state, int64 min, int64 max,
- double parameter)
+getExponentialRand(pg_prng_state *state, int64 min, int64 max, double parameter)
{
double cut,
uniform,
@@ -953,7 +931,7 @@ getExponentialRand(RandomState *random_state, int64 min, int64 max,
Assert(parameter > 0.0);
cut = exp(-parameter);
/* erand in [0, 1), uniform in (0, 1] */
- uniform = 1.0 - pg_erand48(random_state->xseed);
+ uniform = 1.0 - pg_prng_double(state);
/*
* inner expression in (cut, 1] (if parameter > 0), rand in [0, 1)
@@ -966,8 +944,7 @@ getExponentialRand(RandomState *random_state, int64 min, int64 max,
/* random number generator: gaussian distribution from min to max inclusive */
static int64
-getGaussianRand(RandomState *random_state, int64 min, int64 max,
- double parameter)
+getGaussianRand(pg_prng_state *state, int64 min, int64 max, double parameter)
{
double stdev;
double rand;
@@ -990,13 +967,13 @@ getGaussianRand(RandomState *random_state, int64 min, int64 max,
do
{
/*
- * pg_erand48 generates [0,1), but for the basic version of the
+ * pg_prng_double generates [0,1), but for the basic version of the
* Box-Muller transform the two uniformly distributed random numbers
* are expected in (0, 1] (see
* https://en.wikipedia.org/wiki/Box-Muller_transform)
*/
- double rand1 = 1.0 - pg_erand48(random_state->xseed);
- double rand2 = 1.0 - pg_erand48(random_state->xseed);
+ double rand1 = 1.0 - pg_prng_double(state);
+ double rand2 = 1.0 - pg_prng_double(state);
/* Box-Muller basic form transform */
double var_sqrt = sqrt(-2.0 * log(rand1));
@@ -1026,7 +1003,7 @@ getGaussianRand(RandomState *random_state, int64 min, int64 max,
* not be one.
*/
static int64
-getPoissonRand(RandomState *random_state, double center)
+getPoissonRand(pg_prng_state *state, double center)
{
/*
* Use inverse transform sampling to generate a value > 0, such that the
@@ -1034,8 +1011,8 @@ getPoissonRand(RandomState *random_state, double center)
*/
double uniform;
- /* erand in [0, 1), uniform in (0, 1] */
- uniform = 1.0 - pg_erand48(random_state->xseed);
+ /* pseudo-random value in [0, 1), uniform in (0, 1] */
+ uniform = 1.0 - pg_prng_double(state);
return (int64) (-log(uniform) * center + 0.5);
}
@@ -1048,7 +1025,7 @@ getPoissonRand(RandomState *random_state, double center)
* This works for s > 1.0, but may perform badly for s very close to 1.0.
*/
static int64
-computeIterativeZipfian(RandomState *random_state, int64 n, double s)
+computeIterativeZipfian(pg_prng_state *state, int64 n, double s)
{
double b = pow(2.0, s - 1.0);
double x,
@@ -1063,8 +1040,8 @@ computeIterativeZipfian(RandomState *random_state, int64 n, double s)
while (true)
{
/* random variates */
- u = pg_erand48(random_state->xseed);
- v = pg_erand48(random_state->xseed);
+ u = pg_prng_double(state);
+ v = pg_prng_double(state);
x = floor(pow(u, -1.0 / (s - 1.0)));
@@ -1078,14 +1055,14 @@ computeIterativeZipfian(RandomState *random_state, int64 n, double s)
/* random number generator: zipfian distribution from min to max inclusive */
static int64
-getZipfianRand(RandomState *random_state, int64 min, int64 max, double s)
+getZipfianRand(pg_prng_state *state, int64 min, int64 max, double s)
{
int64 n = max - min + 1;
/* abort if parameter is invalid */
Assert(MIN_ZIPFIAN_PARAM <= s && s <= MAX_ZIPFIAN_PARAM);
- return min - 1 + computeIterativeZipfian(random_state, n, s);
+ return min - 1 + computeIterativeZipfian(state, n, s);
}
/*
@@ -1142,7 +1119,7 @@ getHashMurmur2(int64 val, uint64 seed)
* For small sizes, this generates each of the (size!) possible permutations
* of integers in the range [0, size) with roughly equal probability. Once
* the size is larger than 20, the number of possible permutations exceeds the
- * number of distinct states of the internal pseudorandom number generators,
+ * number of distinct states of the internal pseudorandom number generator,
* and so not all possible permutations can be generated, but the permutations
* chosen should continue to give the appearance of being random.
*
@@ -1152,25 +1129,19 @@ getHashMurmur2(int64 val, uint64 seed)
static int64
permute(const int64 val, const int64 isize, const int64 seed)
{
- RandomState random_state1;
- RandomState random_state2;
- uint64 size;
- uint64 v;
- int masklen;
- uint64 mask;
- int i;
+ /* using a high-end PRNG is probably overkill */
+ pg_prng_state state;
+ uint64 size;
+ uint64 v;
+ int masklen;
+ uint64 mask;
+ int i;
if (isize < 2)
return 0; /* nothing to permute */
- /* Initialize a pair of random states using the seed */
- random_state1.xseed[0] = seed & 0xFFFF;
- random_state1.xseed[1] = (seed >> 16) & 0xFFFF;
- random_state1.xseed[2] = (seed >> 32) & 0xFFFF;
-
- random_state2.xseed[0] = (((uint64) seed) >> 48) & 0xFFFF;
- random_state2.xseed[1] = seed & 0xFFFF;
- random_state2.xseed[2] = (seed >> 16) & 0xFFFF;
+ /* Initialize prng state using the seed */
+ pg_prng_seed(&state, (uint64) seed);
/* Computations are performed on unsigned values */
size = (uint64) isize;
@@ -1216,8 +1187,8 @@ permute(const int64 val, const int64 isize, const int64 seed)
t;
/* Random multiply (by an odd number), XOR and rotate of lower half */
- m = (uint64) getrand(&random_state1, 0, mask) | 1;
- r = (uint64) getrand(&random_state2, 0, mask);
+ m = (pg_prng_uint64(&state) & mask) | 1;
+ r = pg_prng_uint64(&state) & mask;
if (v <= mask)
{
v = ((v * m) ^ r) & mask;
@@ -1225,8 +1196,8 @@ permute(const int64 val, const int64 isize, const int64 seed)
}
/* Random multiply (by an odd number), XOR and rotate of upper half */
- m = (uint64) getrand(&random_state1, 0, mask) | 1;
- r = (uint64) getrand(&random_state2, 0, mask);
+ m = (pg_prng_uint64(&state) & mask) | 1;
+ r = pg_prng_uint64(&state) & mask;
t = size - 1 - v;
if (t <= mask)
{
@@ -1236,7 +1207,7 @@ permute(const int64 val, const int64 isize, const int64 seed)
}
/* Random offset */
- r = (uint64) getrand(&random_state2, 0, size - 1);
+ r = pg_prng_uint64(&state) % (size - 1);
v = (v + r) % size;
}
@@ -3831,7 +3802,7 @@ doLog(TState *thread, CState *st,
* to the random sample.
*/
if (sample_rate != 0.0 &&
- pg_erand48(thread->ts_sample_rs.xseed) > sample_rate)
+ pg_prng_double(&thread->ts_sample_rs) > sample_rate)
return;
/* should we aggregate the results or not? */
@@ -5770,12 +5741,11 @@ set_random_seed(const char *seed)
if (seed != NULL)
pg_log_info("setting random seed to %llu", (unsigned long long) iseed);
+
random_seed = iseed;
/* Fill base_random_sequence with low-order bits of seed */
- base_random_sequence.xseed[0] = iseed & 0xFFFF;
- base_random_sequence.xseed[1] = (iseed >> 16) & 0xFFFF;
- base_random_sequence.xseed[2] = (iseed >> 32) & 0xFFFF;
+ pg_prng_seed(&base_random_sequence, (uint64_t) iseed);
return true;
}
@@ -6449,9 +6419,7 @@ main(int argc, char **argv)
/* set default seed for hash functions */
if (lookupVariable(&state[0], "default_seed") == NULL)
{
- uint64 seed =
- ((uint64) pg_jrand48(base_random_sequence.xseed) & 0xFFFFFFFF) |
- (((uint64) pg_jrand48(base_random_sequence.xseed) & 0xFFFFFFFF) << 32);
+ uint64 seed = pg_prng_uint64(&base_random_sequence);
for (i = 0; i < nclients; i++)
if (!putVariableInt(&state[i], "startup", "default_seed", (int64) seed))
diff --git a/src/bin/pgbench/t/001_pgbench_with_server.pl b/src/bin/pgbench/t/001_pgbench_with_server.pl
index 69ffa595dd..feec9a377b 100644
--- a/src/bin/pgbench/t/001_pgbench_with_server.pl
+++ b/src/bin/pgbench/t/001_pgbench_with_server.pl
@@ -379,9 +379,9 @@ $node->pgbench(
# After explicit seeding, the four random checks (1-3,20) are
# deterministic
- qr{command=1.: int 13\b}, # uniform random
- qr{command=2.: int 116\b}, # exponential random
- qr{command=3.: int 1498\b}, # gaussian random
+ qr{command=1.: int 17\b}, # uniform random
+ qr{command=2.: int 108\b}, # exponential random
+ qr{command=3.: int 1452\b}, # gaussian random
qr{command=4.: int 4\b},
qr{command=5.: int 5\b},
qr{command=6.: int 6\b},
@@ -448,6 +448,7 @@ $node->pgbench(
qr{command=109.: boolean true\b},
qr{command=110.: boolean true\b},
qr{command=111.: boolean true\b},
+ qr{command=113.: boolean true\b},
],
'pgbench expressions',
{
@@ -591,8 +592,17 @@ SELECT :v0, :v1, :v2, :v3;
\set t debug(0 <= :p and :p < :size and :p = permute(:v + :size, :size) and :p <> permute(:v + 1, :size))
-- actual values
\set t debug(permute(:v, 1) = 0)
-\set t debug(permute(0, 2, 5432) = 0 and permute(1, 2, 5432) = 1 and \
- permute(0, 2, 5435) = 1 and permute(1, 2, 5435) = 0)
+\set t debug(permute(0, 2, 5431) = 1 and permute(1, 2, 5431) = 0 and \
+ permute(0, 2, 5432) = 0 and permute(1, 2, 5432) = 1)
+-- 63 bits tests for checking permute portability across architectures
+\set size debug(:max - 10)
+\set t debug(permute(:size-1, :size, 5432) = 4352241160009873020 and \
+ permute(:size-2, :size, 5432) = 4990004119691638710 and \
+ permute(:size-3, :size, 5432) = 5868029867256127549 and \
+ permute(:size-4, :size, 5432) = 1238830324886341378 and \
+ permute(:size-5, :size, 5432) = 7415914367102906897 and \
+ permute(:size-6, :size, 5432) = 3214501037984818995 and \
+ permute(:size-7, :size, 5432) = 600660351261124695)
}
});
diff --git a/src/common/Makefile b/src/common/Makefile
index 880722fcf5..31c0dd366d 100644
--- a/src/common/Makefile
+++ b/src/common/Makefile
@@ -66,6 +66,7 @@ OBJS_COMMON = \
md5_common.o \
pg_get_line.o \
pg_lzcompress.o \
+ pg_prng.o \
pgfnames.o \
psprintf.o \
relpath.o \
diff --git a/src/common/pg_prng.c b/src/common/pg_prng.c
new file mode 100644
index 0000000000..3464e52459
--- /dev/null
+++ b/src/common/pg_prng.c
@@ -0,0 +1,185 @@
+/*
+ * Pseudo-Random Number Generator
+ *
+ * Copyright (c) 2021-2021, PostgreSQL Global Development Group
+ *
+ * https://en.wikipedia.org/wiki/List_of_random_number_generators
+ *
+ * We chose a xoshiro 128 bit state to have a small, fast PRNG suitable
+ * for generating reasonably good quality uniform 64 bit data.
+ *
+ * About these generators: https://prng.di.unimi.it/
+ */
+
+#include "c.h"
+#include "common/pg_prng.h"
+#include "port/pg_bitutils.h"
+#include <math.h>
+
+/* global state */
+pg_prng_state pg_global_prng_state;
+
+#define LAST_32BIT_MASK UINT64CONST(0x00000000FFFFFFFF)
+#define LAST_31BIT_MASK UINT64CONST(0x000000007FFFFFFF)
+#define LAST_63BIT_MASK UINT64CONST(0x7FFFFFFFFFFFFFFF)
+#define DMANTISSA_MASK UINT64CONST(0x000FFFFFFFFFFFFF)
+
+/* 64-bits rotate left */
+static inline uint64
+rotl(const uint64 x, const int bits)
+{
+ return (x << bits) | (x >> (64 - bits));
+}
+
+/* another 64-bits generator is used for state initialization or iterations */
+static uint64
+splitmix64(uint64 * state)
+{
+ /* state update */
+ uint64 val = (*state += UINT64CONST(0x9E3779B97f4A7C15));
+
+ /* value extraction */
+ val = (val ^ (val >> 30)) * UINT64CONST(0xBF58476D1CE4E5B9);
+ val = (val ^ (val >> 27)) * UINT64CONST(0x94D049BB133111EB);
+
+ return val ^ (val >> 31);
+}
+
+/* seed prng state from a 64 bits integer, ensuring non zero */
+void
+pg_prng_seed(pg_prng_state *state, uint64 seed)
+{
+ state->s0 = splitmix64(&seed);
+ state->s1 = splitmix64(&seed);
+}
+
+/* seed with 53 bits (mantissa & sign) from a float */
+void
+pg_prng_fseed(pg_prng_state *state, double fseed)
+{
+ uint64 seed = (int64) (((double) DMANTISSA_MASK) * fseed);
+ pg_prng_seed(state, seed);
+}
+
+/* strong random seeding */
+bool
+pg_prng_strong_seed(pg_prng_state *state)
+{
+ bool ok = pg_strong_random((void *) state, sizeof(pg_prng_state));
+
+ /* avoid zero with Donald Knuth's LCG parameters */
+ if (unlikely(state->s0 == 0 && state->s1 == 0))
+ {
+ /* should it warn that something is amiss if we get there? */
+ pg_prng_state def = PG_PRNG_DEFAULT_STATE;
+ *state = def;
+ }
+
+ return ok;
+}
+
+/* basic generator & state update used for all types */
+static uint64
+xoroshiro128ss(pg_prng_state *state)
+{
+ const uint64 s0 = state->s0,
+ sx = state->s1 ^ s0,
+ val = rotl(s0 * 5, 7) * 9;
+
+ /* update state */
+ state->s0 = rotl(s0, 24) ^ sx ^ (sx << 16);
+ state->s1 = rotl(sx, 37);
+
+ return val;
+}
+
+/* return a uniform uint64 */
+uint64
+pg_prng_uint64(pg_prng_state *state)
+{
+ return xoroshiro128ss(state);
+}
+
+/* return a uniform uint64 in range [rmin, rmax], or rmin if range is empty */
+uint64
+pg_prng_uint64_range(pg_prng_state *state, uint64 rmin, uint64 rmax)
+{
+ uint64 val;
+
+ if (likely(rmax > rmin))
+ {
+ uint64 range = rmax - rmin;
+
+ /* bit position is between 0 and 63, so rshift >= 0 */
+ uint32 rshift = 63 - pg_leftmost_one_pos64(range);
+
+ /*
+ * iterate with a bitmask rejection method.
+ * the prng may advance by several states or none,
+ * depending on the range value.
+ */
+ do
+ {
+ val = xoroshiro128ss(state) >> rshift;
+ }
+ while (unlikely(val > range));
+ }
+ else
+ val = 0;
+
+ return rmin + val;
+}
+
+/* return a uniform int64 in [-2^63, 2^63) */
+int64
+pg_prng_int64(pg_prng_state *state)
+{
+ return (int64) xoroshiro128ss(state);
+}
+
+/* return a uniform int64 in [0, 2^63) */
+int64
+pg_prng_int64p(pg_prng_state *state)
+{
+ return (int64) xoroshiro128ss(state) & LAST_63BIT_MASK;
+}
+
+/* return a uniform uint32 */
+uint32
+pg_prng_uint32(pg_prng_state *state)
+{
+ const uint64 v = xoroshiro128ss(state);
+ return (uint32) (((v >> 32) ^ v) & LAST_32BIT_MASK);
+}
+
+/* return a uniform int32 in [-2^31, 2^31) */
+int32
+pg_prng_int32(pg_prng_state *state)
+{
+ const uint64 v = xoroshiro128ss(state);
+ return (int32) (((v >> 32) ^ v) & LAST_32BIT_MASK);
+}
+
+/* return a uniform int32 in [0, 2^31) */
+int32
+pg_prng_int32p(pg_prng_state *state)
+{
+ const uint64 v = xoroshiro128ss(state);
+ return (int32) (((v >> 32) ^ v) & LAST_31BIT_MASK);
+}
+
+/* return a uniform double in [0.0, 1.0) */
+double
+pg_prng_double(pg_prng_state *state)
+{
+ uint64 v = xoroshiro128ss(state);
+ return ldexp((double) (v & DMANTISSA_MASK), -52);
+}
+
+/* return a uniform bool */
+bool
+pg_prng_bool(pg_prng_state *state)
+{
+ uint64 v = xoroshiro128ss(state);
+ return (v & 1) == 1;
+}
diff --git a/src/include/common/pg_prng.h b/src/include/common/pg_prng.h
new file mode 100644
index 0000000000..2d0878e18d
--- /dev/null
+++ b/src/include/common/pg_prng.h
@@ -0,0 +1,39 @@
+/*-------------------------------------------------------------------------
+ *
+ * PRNG: internal Pseudo-Random Number Generator
+ *
+ * Copyright (c) 2021-2021, PostgreSQL Global Development Group
+ *
+ * src/include/common/pg_prng.h
+ *
+ *-------------------------------------------------------------------------
+ */
+#ifndef PG_PRNG_H
+#define PG_PRNG_H
+
+/* 128 bits state */
+typedef struct pg_prng_state {
+ uint64 s0, s1;
+} pg_prng_state;
+
+/* global pseudo-random state */
+extern PGDLLIMPORT pg_prng_state pg_global_prng_state;
+
+/* arbitrarily use Donald Knuth's LCG constants for default state */
+#define PG_PRNG_DEFAULT_STATE \
+ { UINT64CONST(0x5851F42D4C957F2D), UINT64CONST(0x14057B7EF767814F) }
+
+extern void pg_prng_seed(pg_prng_state *state, uint64 seed);
+extern void pg_prng_fseed(pg_prng_state *state, double fseed);
+extern bool pg_prng_strong_seed(pg_prng_state *state);
+extern uint64 pg_prng_uint64(pg_prng_state *state);
+extern uint64 pg_prng_uint64_range(pg_prng_state *state, uint64 rmin, uint64 rmax);
+extern int64 pg_prng_int64(pg_prng_state *state);
+extern int64 pg_prng_int64p(pg_prng_state *state);
+extern uint32 pg_prng_uint32(pg_prng_state *state);
+extern int32 pg_prng_int32(pg_prng_state *state);
+extern int32 pg_prng_int32p(pg_prng_state *state);
+extern double pg_prng_double(pg_prng_state *state);
+extern bool pg_prng_bool(pg_prng_state *state);
+
+#endif /* PG_PRNG_H */
diff --git a/src/include/optimizer/geqo.h b/src/include/optimizer/geqo.h
index 24dcdfb6cc..b28e4f084a 100644
--- a/src/include/optimizer/geqo.h
+++ b/src/include/optimizer/geqo.h
@@ -22,6 +22,7 @@
#ifndef GEQO_H
#define GEQO_H
+#include "common/pg_prng.h"
#include "nodes/pathnodes.h"
#include "optimizer/geqo_gene.h"
@@ -72,8 +73,8 @@ extern double Geqo_seed; /* 0 .. 1 */
*/
typedef struct
{
- List *initial_rels; /* the base relations we are joining */
- unsigned short random_state[3]; /* state for pg_erand48() */
+ List *initial_rels; /* the base relations we are joining */
+ pg_prng_state random_state; /* PRNG state */
} GeqoPrivateData;
diff --git a/src/include/port.h b/src/include/port.h
index 49b4d38131..806fb795ed 100644
--- a/src/include/port.h
+++ b/src/include/port.h
@@ -362,11 +362,6 @@ extern int gettimeofday(struct timeval *tp, struct timezone *tzp);
#define pgoff_t off_t
#endif
-extern double pg_erand48(unsigned short xseed[3]);
-extern long pg_lrand48(void);
-extern long pg_jrand48(unsigned short xseed[3]);
-extern void pg_srand48(long seed);
-
#ifndef HAVE_FLS
extern int fls(int mask);
#endif
@@ -452,10 +447,6 @@ extern size_t strlcpy(char *dst, const char *src, size_t siz);
extern size_t strnlen(const char *str, size_t maxlen);
#endif
-#if !defined(HAVE_RANDOM)
-extern long random(void);
-#endif
-
#ifndef HAVE_SETENV
extern int setenv(const char *name, const char *value, int overwrite);
#endif
@@ -464,10 +455,6 @@ extern int setenv(const char *name, const char *value, int overwrite);
extern int unsetenv(const char *name);
#endif
-#ifndef HAVE_SRANDOM
-extern void srandom(unsigned int seed);
-#endif
-
#ifndef HAVE_DLOPEN
extern void *dlopen(const char *file, int mode);
extern void *dlsym(void *handle, const char *symbol);
diff --git a/src/include/utils/sampling.h b/src/include/utils/sampling.h
index a58d14281b..c0b1c6a645 100644
--- a/src/include/utils/sampling.h
+++ b/src/include/utils/sampling.h
@@ -13,15 +13,14 @@
#ifndef SAMPLING_H
#define SAMPLING_H
+#include "common/pg_prng.h"
#include "storage/block.h" /* for typedef BlockNumber */
/* Random generator for sampling code */
-typedef unsigned short SamplerRandomState[3];
-
extern void sampler_random_init_state(long seed,
- SamplerRandomState randstate);
-extern double sampler_random_fract(SamplerRandomState randstate);
+ pg_prng_state *randstate);
+extern double sampler_random_fract(pg_prng_state *randstate);
/* Block sampling methods */
@@ -32,7 +31,7 @@ typedef struct
int n; /* desired sample size */
BlockNumber t; /* current block number */
int m; /* blocks selected so far */
- SamplerRandomState randstate; /* random generator state */
+ pg_prng_state randstate; /* random generator state */
} BlockSamplerData;
typedef BlockSamplerData *BlockSampler;
@@ -46,8 +45,9 @@ extern BlockNumber BlockSampler_Next(BlockSampler bs);
typedef struct
{
- double W;
- SamplerRandomState randstate; /* random generator state */
+ double W;
+ pg_prng_state randstate; /* random generator state */
+ bool randstate_initialized;
} ReservoirStateData;
typedef ReservoirStateData *ReservoirState;
diff --git a/src/port/Makefile b/src/port/Makefile
index 52dbf5783f..b3754d8940 100644
--- a/src/port/Makefile
+++ b/src/port/Makefile
@@ -42,7 +42,6 @@ OBJS = \
$(PG_CRC32C_OBJS) \
bsearch_arg.o \
chklocale.o \
- erand48.o \
inet_net_ntop.o \
noblock.o \
path.o \
diff --git a/src/port/erand48.c b/src/port/erand48.c
deleted file mode 100644
index a82ea94220..0000000000
--- a/src/port/erand48.c
+++ /dev/null
@@ -1,136 +0,0 @@
-/*-------------------------------------------------------------------------
- *
- * erand48.c
- *
- * This file supplies pg_erand48() and related functions, which except
- * for the names are just like the POSIX-standard erand48() family.
- * (We don't supply the full set though, only the ones we have found use
- * for in Postgres. In particular, we do *not* implement lcong48(), so
- * that there is no need for the multiplier and addend to be variable.)
- *
- * We used to test for an operating system version rather than
- * unconditionally using our own, but (1) some versions of Cygwin have a
- * buggy erand48() that always returns zero and (2) as of 2011, glibc's
- * erand48() is strangely coded to be almost-but-not-quite thread-safe,
- * which doesn't matter for the backend but is important for pgbench.
- *
- * Portions Copyright (c) 1996-2021, PostgreSQL Global Development Group
- *
- * Portions Copyright (c) 1993 Martin Birgmeier
- * All rights reserved.
- *
- * You may redistribute unmodified or modified versions of this source
- * code provided that the above copyright notice and this and the
- * following conditions are retained.
- *
- * This software is provided ``as is'', and comes with no warranties
- * of any kind. I shall in no event be liable for anything that happens
- * to anyone/anything when using this software.
- *
- * IDENTIFICATION
- * src/port/erand48.c
- *
- *-------------------------------------------------------------------------
- */
-
-#include "c.h"
-
-#include <math.h>
-
-/* These values are specified by POSIX */
-#define RAND48_MULT UINT64CONST(0x0005deece66d)
-#define RAND48_ADD UINT64CONST(0x000b)
-
-/* POSIX specifies 0x330e's use in srand48, but the other bits are arbitrary */
-#define RAND48_SEED_0 (0x330e)
-#define RAND48_SEED_1 (0xabcd)
-#define RAND48_SEED_2 (0x1234)
-
-static unsigned short _rand48_seed[3] = {
- RAND48_SEED_0,
- RAND48_SEED_1,
- RAND48_SEED_2
-};
-
-
-/*
- * Advance the 48-bit value stored in xseed[] to the next "random" number.
- *
- * Also returns the value of that number --- without masking it to 48 bits.
- * If caller uses the result, it must mask off the bits it wants.
- */
-static uint64
-_dorand48(unsigned short xseed[3])
-{
- /*
- * We do the arithmetic in uint64; any type wider than 48 bits would work.
- */
- uint64 in;
- uint64 out;
-
- in = (uint64) xseed[2] << 32 | (uint64) xseed[1] << 16 | (uint64) xseed[0];
-
- out = in * RAND48_MULT + RAND48_ADD;
-
- xseed[0] = out & 0xFFFF;
- xseed[1] = (out >> 16) & 0xFFFF;
- xseed[2] = (out >> 32) & 0xFFFF;
-
- return out;
-}
-
-
-/*
- * Generate a random floating-point value using caller-supplied state.
- * Values are uniformly distributed over the interval [0.0, 1.0).
- */
-double
-pg_erand48(unsigned short xseed[3])
-{
- uint64 x = _dorand48(xseed);
-
- return ldexp((double) (x & UINT64CONST(0xFFFFFFFFFFFF)), -48);
-}
-
-/*
- * Generate a random non-negative integral value using internal state.
- * Values are uniformly distributed over the interval [0, 2^31).
- */
-long
-pg_lrand48(void)
-{
- uint64 x = _dorand48(_rand48_seed);
-
- return (x >> 17) & UINT64CONST(0x7FFFFFFF);
-}
-
-/*
- * Generate a random signed integral value using caller-supplied state.
- * Values are uniformly distributed over the interval [-2^31, 2^31).
- */
-long
-pg_jrand48(unsigned short xseed[3])
-{
- uint64 x = _dorand48(xseed);
-
- return (int32) ((x >> 16) & UINT64CONST(0xFFFFFFFF));
-}
-
-/*
- * Initialize the internal state using the given seed.
- *
- * Per POSIX, this uses only 32 bits from "seed" even if "long" is wider.
- * Hence, the set of possible seed values is smaller than it could be.
- * Better practice is to use caller-supplied state and initialize it with
- * random bits obtained from a high-quality source of random bits.
- *
- * Note: POSIX specifies a function seed48() that allows all 48 bits
- * of the internal state to be set, but we don't currently support that.
- */
-void
-pg_srand48(long seed)
-{
- _rand48_seed[0] = RAND48_SEED_0;
- _rand48_seed[1] = (unsigned short) seed;
- _rand48_seed[2] = (unsigned short) (seed >> 16);
-}
diff --git a/src/port/random.c b/src/port/random.c
deleted file mode 100644
index 2dd59a0829..0000000000
--- a/src/port/random.c
+++ /dev/null
@@ -1,25 +0,0 @@
-/*-------------------------------------------------------------------------
- *
- * random.c
- * random() wrapper
- *
- * Portions Copyright (c) 1996-2021, PostgreSQL Global Development Group
- * Portions Copyright (c) 1994, Regents of the University of California
- *
- *
- * IDENTIFICATION
- * src/port/random.c
- *
- *-------------------------------------------------------------------------
- */
-
-#include "c.h"
-
-#include <math.h>
-
-
-long
-random(void)
-{
- return pg_lrand48();
-}
diff --git a/src/port/srandom.c b/src/port/srandom.c
deleted file mode 100644
index cf1007b2ef..0000000000
--- a/src/port/srandom.c
+++ /dev/null
@@ -1,25 +0,0 @@
-/*-------------------------------------------------------------------------
- *
- * srandom.c
- * srandom() wrapper
- *
- * Portions Copyright (c) 1996-2021, PostgreSQL Global Development Group
- * Portions Copyright (c) 1994, Regents of the University of California
- *
- *
- * IDENTIFICATION
- * src/port/srandom.c
- *
- *-------------------------------------------------------------------------
- */
-
-#include "c.h"
-
-#include <math.h>
-
-
-void
-srandom(unsigned int seed)
-{
- pg_srand48((long int) seed);
-}
diff --git a/src/test/modules/test_bloomfilter/test_bloomfilter.c b/src/test/modules/test_bloomfilter/test_bloomfilter.c
index 96c5011428..c60220de7b 100644
--- a/src/test/modules/test_bloomfilter/test_bloomfilter.c
+++ b/src/test/modules/test_bloomfilter/test_bloomfilter.c
@@ -13,6 +13,7 @@
#include "postgres.h"
#include "fmgr.h"
+#include "common/pg_prng.h"
#include "lib/bloomfilter.h"
#include "miscadmin.h"
@@ -85,7 +86,7 @@ create_and_test_bloom(int power, int64 nelements, int callerseed)
* random seed can be recreated through callerseed if the need arises.
* (Don't assume that RAND_MAX cannot exceed PG_INT32_MAX.)
*/
- seed = callerseed < 0 ? random() % PG_INT32_MAX : callerseed;
+ seed = callerseed < 0 ? pg_prng_int32p(&pg_global_prng_state) : callerseed;
/* Create Bloom filter, populate it, and report on false positive rate */
filter = bloom_create(nelements, bloom_work_mem, seed);
diff --git a/src/test/modules/test_integerset/test_integerset.c b/src/test/modules/test_integerset/test_integerset.c
index 21c6f49b37..6d251b110a 100644
--- a/src/test/modules/test_integerset/test_integerset.c
+++ b/src/test/modules/test_integerset/test_integerset.c
@@ -12,6 +12,7 @@
*/
#include "postgres.h"
+#include "common/pg_prng.h"
#include "fmgr.h"
#include "lib/integerset.h"
#include "miscadmin.h"
@@ -99,12 +100,20 @@ static void check_with_filler(IntegerSet *intset, uint64 x, uint64 value, uint64
static void test_single_value_and_filler(uint64 value, uint64 filler_min, uint64 filler_max);
static void test_huge_distances(void);
+static pg_prng_state pr_state;
+
/*
* SQL-callable entry point to perform all tests.
*/
Datum
test_integerset(PG_FUNCTION_ARGS)
{
+ if(unlikely(!pg_prng_strong_seed(&pr_state)))
+ {
+ elog(ERROR, "pg_prng_strong_seed() failed");
+ PG_RETURN_VOID();
+ }
+
/* Tests for various corner cases */
test_empty();
test_huge_distances();
@@ -248,8 +257,7 @@ test_pattern(const test_spec *spec)
* only a small part of the integer space is used. We would very
* rarely hit values that are actually in the set.
*/
- x = (pg_lrand48() << 31) | pg_lrand48();
- x = x % (last_int + 1000);
+ x = pg_prng_uint64(&pr_state) % (last_int + 1000);
/* Do we expect this value to be present in the set? */
if (x >= last_int)
@@ -571,7 +579,7 @@ test_huge_distances(void)
*/
while (num_values < 1000)
{
- val += pg_lrand48();
+ val += pg_prng_uint32(&pr_state);
values[num_values++] = val;
}
diff --git a/src/test/modules/test_rbtree/test_rbtree.c b/src/test/modules/test_rbtree/test_rbtree.c
index 713ebd1b26..d5496ced5b 100644
--- a/src/test/modules/test_rbtree/test_rbtree.c
+++ b/src/test/modules/test_rbtree/test_rbtree.c
@@ -14,6 +14,7 @@
#include "postgres.h"
#include "fmgr.h"
+#include "common/pg_prng.h"
#include "lib/rbtree.h"
#include "utils/memutils.h"
@@ -108,7 +109,7 @@ GetPermutation(int size)
*/
for (i = 1; i < size; i++)
{
- int j = random() % (i + 1);
+ int j = pg_prng_uint32(&pg_global_prng_state) % (i + 1);
if (j < i) /* avoid fetching undefined data if j=i */
permutation[i] = permutation[j];
@@ -320,7 +321,7 @@ testdelete(int size, int delsize)
for (i = 0; i < delsize; i++)
{
- int k = random() % size;
+ int k = pg_prng_uint32(&pg_global_prng_state) % size;
while (chosen[k])
k = (k + 1) % size;
diff --git a/src/tools/msvc/Mkvcbuild.pm b/src/tools/msvc/Mkvcbuild.pm
index 41172eab36..5a374a4727 100644
--- a/src/tools/msvc/Mkvcbuild.pm
+++ b/src/tools/msvc/Mkvcbuild.pm
@@ -99,9 +99,9 @@ sub mkvcbuild
$solution = CreateSolution($vsVersion, $config);
our @pgportfiles = qw(
- chklocale.c explicit_bzero.c fls.c getpeereid.c getrusage.c inet_aton.c random.c
- srandom.c getaddrinfo.c gettimeofday.c inet_net_ntop.c kill.c open.c
- erand48.c snprintf.c strlcat.c strlcpy.c dirmod.c noblock.c path.c
+ chklocale.c explicit_bzero.c fls.c getpeereid.c getrusage.c inet_aton.c
+ getaddrinfo.c gettimeofday.c inet_net_ntop.c kill.c open.c
+ snprintf.c strlcat.c strlcpy.c dirmod.c noblock.c path.c
dirent.c dlopen.c getopt.c getopt_long.c link.c
pread.c preadv.c pwrite.c pwritev.c pg_bitutils.c
pg_strong_random.c pgcheckdir.c pgmkdirp.c pgsleep.c pgstrcasecmp.c
@@ -127,9 +127,9 @@ sub mkvcbuild
config_info.c controldata_utils.c d2s.c encnames.c exec.c
f2s.c file_perm.c file_utils.c hashfn.c ip.c jsonapi.c
keywords.c kwlookup.c link-canary.c md5_common.c
- pg_get_line.c pg_lzcompress.c pgfnames.c psprintf.c relpath.c rmtree.c
- saslprep.c scram-common.c string.c stringinfo.c unicode_norm.c username.c
- wait_error.c wchar.c);
+ pg_get_line.c pg_lzcompress.c pg_prng.c pgfnames.c psprintf.c relpath.c
+ rmtree.c saslprep.c scram-common.c string.c stringinfo.c unicode_norm.c
+ username.c wait_error.c wchar.c);
if ($solution->{options}->{openssl})
{
diff --git a/src/tools/testint128.c b/src/tools/testint128.c
index 71c345969a..446ddfac65 100644
--- a/src/tools/testint128.c
+++ b/src/tools/testint128.c
@@ -27,6 +27,7 @@
#endif
#include "common/int128.h"
+#include "common/pg_prng.h"
/*
* We assume the parts of this union are laid out compatibly.
@@ -61,27 +62,11 @@ my_int128_compare(int128 x, int128 y)
return 0;
}
-/*
- * Get a random uint64 value.
- * We don't assume random() is good for more than 16 bits.
- */
-static uint64
-get_random_uint64(void)
-{
- uint64 x;
-
- x = (uint64) (random() & 0xFFFF) << 48;
- x |= (uint64) (random() & 0xFFFF) << 32;
- x |= (uint64) (random() & 0xFFFF) << 16;
- x |= (uint64) (random() & 0xFFFF);
- return x;
-}
-
/*
* Main program.
*
* Generates a lot of random numbers and tests the implementation for each.
- * The results should be reproducible, since we don't call srandom().
+ * The results should be reproducible, since we fix the prng state (hmmm...).
*
* You can give a loop count if you don't like the default 1B iterations.
*/
@@ -90,6 +75,8 @@ main(int argc, char **argv)
{
long count;
+ pg_prng_seed(&pg_global_prng_state, 0);
+
if (argc >= 2)
count = strtol(argv[1], NULL, 0);
else
@@ -97,9 +84,9 @@ main(int argc, char **argv)
while (count-- > 0)
{
- int64 x = get_random_uint64();
- int64 y = get_random_uint64();
- int64 z = get_random_uint64();
+ int64 x = pg_prng_uint64(&pg_global_prng_state);
+ int64 y = pg_prng_uint64(&pg_global_prng_state);
+ int64 z = pg_prng_uint64(&pg_global_prng_state);
test128 t1;
test128 t2;
