From: Andres Freund <andres@anarazel.de>
Date: Wed, 25 Mar 2015 21:39:42 +0000 (+0100)
Subject: Centralize definition of integer limits.
X-Git-Tag: REL9_5_ALPHA1~553
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=83ff1618bc9d4e530d3ef2a668a71326784a753c;p=postgresql

Centralize definition of integer limits.

Several submitted and even committed patches have run into the problem
that C89, our baseline, does not provide minimum/maximum values for
various integer datatypes. C99's stdint.h does, but we can't rely on
it.

Several parts of the code defined limits locally, so instead centralize
the definitions to c.h.

This patch also changes the more obvious usages of literal limit values;
there's more places that could be changed, but it's less clear whether
it's beneficial to change those.

Author: Andrew Gierth
Discussion: 87619tc5wc.fsf@news-spur.riddles.org.uk
---

diff --git a/contrib/btree_gist/btree_ts.c b/contrib/btree_gist/btree_ts.c
index b9c2b49ef3..d472d494c9 100644
--- a/contrib/btree_gist/btree_ts.c
+++ b/contrib/btree_gist/btree_ts.c
@@ -153,7 +153,7 @@ ts_dist(PG_FUNCTION_ARGS)
 		p->day = INT_MAX;
 		p->month = INT_MAX;
 #ifdef HAVE_INT64_TIMESTAMP
-		p->time = INT64CONST(0x7FFFFFFFFFFFFFFF);
+		p->time = INT64_MAX;
 #else
 		p->time = DBL_MAX;
 #endif
@@ -181,7 +181,7 @@ tstz_dist(PG_FUNCTION_ARGS)
 		p->day = INT_MAX;
 		p->month = INT_MAX;
 #ifdef HAVE_INT64_TIMESTAMP
-		p->time = INT64CONST(0x7FFFFFFFFFFFFFFF);
+		p->time = INT64_MAX;
 #else
 		p->time = DBL_MAX;
 #endif
diff --git a/contrib/intarray/_int_gist.c b/contrib/intarray/_int_gist.c
index 876a7b9a8a..07108eb15e 100644
--- a/contrib/intarray/_int_gist.c
+++ b/contrib/intarray/_int_gist.c
@@ -3,6 +3,8 @@
  */
 #include "postgres.h"
 
+#include <limits.h>
+
 #include "access/gist.h"
 #include "access/skey.h"
 
@@ -191,7 +193,7 @@ g_int_compress(PG_FUNCTION_ARGS)
 		cand = 1;
 		while (len > MAXNUMRANGE * 2)
 		{
-			min = 0x7fffffff;
+			min = INT_MAX;
 			for (i = 2; i < len; i += 2)
 				if (min > (dr[i] - dr[i - 1]))
 				{
diff --git a/contrib/pgbench/pgbench.c b/contrib/pgbench/pgbench.c
index 706fdf5b19..822adfd581 100644
--- a/contrib/pgbench/pgbench.c
+++ b/contrib/pgbench/pgbench.c
@@ -49,10 +49,6 @@
 #include <sys/resource.h>		/* for getrlimit */
 #endif
 
-#ifndef INT64_MAX
-#define INT64_MAX	INT64CONST(0x7FFFFFFFFFFFFFFF)
-#endif
-
 #ifndef M_PI
 #define M_PI 3.14159265358979323846
 #endif
@@ -453,7 +449,7 @@ strtoint64(const char *str)
 		 */
 		if (strncmp(ptr, "9223372036854775808", 19) == 0)
 		{
-			result = -INT64CONST(0x7fffffffffffffff) - 1;
+			result = INT64_MIN;
 			ptr += 19;
 			goto gotdigits;
 		}
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 2c6ae12b8d..751253ba03 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1408,7 +1408,7 @@ WALInsertLockAcquireExclusive(void)
 	{
 		LWLockAcquireWithVar(&WALInsertLocks[i].l.lock,
 							 &WALInsertLocks[i].l.insertingAt,
-							 UINT64CONST(0xFFFFFFFFFFFFFFFF));
+							 UINT64_MAX);
 	}
 	LWLockAcquireWithVar(&WALInsertLocks[i].l.lock,
 						 &WALInsertLocks[i].l.insertingAt,
diff --git a/src/backend/tsearch/wparser_def.c b/src/backend/tsearch/wparser_def.c
index ca5b54358a..d95fdb1fab 100644
--- a/src/backend/tsearch/wparser_def.c
+++ b/src/backend/tsearch/wparser_def.c
@@ -14,6 +14,8 @@
 
 #include "postgres.h"
 
+#include <limits.h>
+
 #include "catalog/pg_collation.h"
 #include "commands/defrem.h"
 #include "tsearch/ts_locale.h"
@@ -2047,7 +2049,7 @@ hlCover(HeadlineParsedText *prs, TSQuery query, int *p, int *q)
 	int			pos = *p;
 
 	*q = -1;
-	*p = 0x7fffffff;
+	*p = INT_MAX;
 
 	for (j = 0; j < query->size; j++)
 	{
@@ -2258,7 +2260,7 @@ mark_hl_fragments(HeadlineParsedText *prs, TSQuery query, int highlight,
 	for (f = 0; f < max_fragments; f++)
 	{
 		maxitems = 0;
-		minwords = 0x7fffffff;
+		minwords = INT32_MAX;
 		minI = -1;
 
 		/*
diff --git a/src/backend/utils/adt/int8.c b/src/backend/utils/adt/int8.c
index 56d909a4f6..b3a1191887 100644
--- a/src/backend/utils/adt/int8.c
+++ b/src/backend/utils/adt/int8.c
@@ -78,7 +78,7 @@ scanint8(const char *str, bool errorOK, int64 *result)
 		 */
 		if (strncmp(ptr, "9223372036854775808", 19) == 0)
 		{
-			tmp = -INT64CONST(0x7fffffffffffffff) - 1;
+			tmp = INT64_MIN;
 			ptr += 19;
 			goto gotdigits;
 		}
diff --git a/src/backend/utils/adt/numutils.c b/src/backend/utils/adt/numutils.c
index d77799acfe..585da1e732 100644
--- a/src/backend/utils/adt/numutils.c
+++ b/src/backend/utils/adt/numutils.c
@@ -190,7 +190,7 @@ pg_lltoa(int64 value, char *a)
 	 * Avoid problems with the most negative integer not being representable
 	 * as a positive integer.
 	 */
-	if (value == (-INT64CONST(0x7FFFFFFFFFFFFFFF) - 1))
+	if (value == INT64_MIN)
 	{
 		memcpy(a, "-9223372036854775808", 21);
 		return;
diff --git a/src/backend/utils/adt/timestamp.c b/src/backend/utils/adt/timestamp.c
index 723c67087e..33e859d35e 100644
--- a/src/backend/utils/adt/timestamp.c
+++ b/src/backend/utils/adt/timestamp.c
@@ -44,14 +44,6 @@
 
 #define SAMESIGN(a,b)	(((a) < 0) == ((b) < 0))
 
-#ifndef INT64_MAX
-#define INT64_MAX	INT64CONST(0x7FFFFFFFFFFFFFFF)
-#endif
-
-#ifndef INT64_MIN
-#define INT64_MIN	(-INT64CONST(0x7FFFFFFFFFFFFFFF) - 1)
-#endif
-
 /* Set at postmaster start */
 TimestampTz PgStartTime;
 
diff --git a/src/backend/utils/adt/tsrank.c b/src/backend/utils/adt/tsrank.c
index 733203ec7b..a3066fa794 100644
--- a/src/backend/utils/adt/tsrank.c
+++ b/src/backend/utils/adt/tsrank.c
@@ -13,6 +13,7 @@
  */
 #include "postgres.h"
 
+#include <limits.h>
 #include <math.h>
 
 #include "tsearch/ts_utils.h"
@@ -555,7 +556,7 @@ Cover(DocRepresentation *doc, int len, QueryRepresentation *qr, CoverExt *ext)
 
 	memset(qr->operandexist, 0, sizeof(bool) * qr->query->size);
 
-	ext->p = 0x7fffffff;
+	ext->p = INT_MAX;
 	ext->q = 0;
 	ptr = doc + ext->pos;
 
diff --git a/src/backend/utils/adt/txid.c b/src/backend/utils/adt/txid.c
index f973ef936c..31f8033ae4 100644
--- a/src/backend/utils/adt/txid.c
+++ b/src/backend/utils/adt/txid.c
@@ -34,7 +34,7 @@
 
 
 /* txid will be signed int8 in database, so must limit to 63 bits */
-#define MAX_TXID   UINT64CONST(0x7FFFFFFFFFFFFFFF)
+#define MAX_TXID   ((uint64) INT64_MAX)
 
 /* Use unsigned variant internally */
 typedef uint64 txid;
diff --git a/src/include/c.h b/src/include/c.h
index 744721860c..e7ee5105a2 100644
--- a/src/include/c.h
+++ b/src/include/c.h
@@ -249,6 +249,36 @@ typedef uint8 bits8;			/* >= 8 bits */
 typedef uint16 bits16;			/* >= 16 bits */
 typedef uint32 bits32;			/* >= 32 bits */
 
+/* should be defined in stdint.h, but we guarantee them here */
+#ifndef INT8_MIN
+#define INT8_MIN	(-0x7F-1)
+#endif
+#ifndef INT8_MAX
+#define INT8_MAX	(0x7F)
+#endif
+#ifndef INT16_MIN
+#define INT16_MIN	(-0x7FFF-1)
+#endif
+#ifndef INT16_MAX
+#define INT16_MAX	(0x7FFF)
+#endif
+#ifndef INT32_MIN
+#define INT32_MIN	(-0x7FFFFFFF-1)
+#endif
+#ifndef INT32_MAX
+#define INT32_MAX	(0x7FFFFFFF)
+#endif
+
+#ifndef UINT8_MAX
+#define UINT8_MAX	(0xFF)
+#endif
+#ifndef UINT16_MAX
+#define UINT16_MAX	(0xFFFF)
+#endif
+#ifndef UINT32_MAX
+#define UINT32_MAX	(0xFFFFFFFF)
+#endif
+
 /*
  * 64-bit integers
  */
@@ -284,6 +314,17 @@ typedef unsigned long long int uint64;
 #define UINT64CONST(x) ((uint64) x)
 #endif
 
+/* should be defined in stdint.h, but we guarantee them here */
+#ifndef INT64_MIN
+#define INT64_MIN	(-INT64CONST(0x7FFFFFFFFFFFFFFF) - 1)
+#endif
+#ifndef INT64_MAX
+#define INT64_MAX	INT64CONST(0x7FFFFFFFFFFFFFFF)
+#endif
+#ifndef UINT64_MAX
+#define UINT64_MAX	UINT64CONST(0xFFFFFFFFFFFFFFFF)
+#endif
+
 /* snprintf format strings to use for 64-bit integers */
 #define INT64_FORMAT "%" INT64_MODIFIER "d"
 #define UINT64_FORMAT "%" INT64_MODIFIER "u"
diff --git a/src/include/datatype/timestamp.h b/src/include/datatype/timestamp.h
index 6dfaf23cc5..d3450d69a8 100644
--- a/src/include/datatype/timestamp.h
+++ b/src/include/datatype/timestamp.h
@@ -119,8 +119,8 @@ typedef struct
  * DT_NOBEGIN represents timestamp -infinity; DT_NOEND represents +infinity
  */
 #ifdef HAVE_INT64_TIMESTAMP
-#define DT_NOBEGIN		(-INT64CONST(0x7fffffffffffffff) - 1)
-#define DT_NOEND		(INT64CONST(0x7fffffffffffffff))
+#define DT_NOBEGIN		INT64_MIN
+#define DT_NOEND		INT64_MAX
 #else							/* !HAVE_INT64_TIMESTAMP */
 #ifdef HUGE_VAL
 #define DT_NOBEGIN		(-HUGE_VAL)
diff --git a/src/include/executor/instrument.h b/src/include/executor/instrument.h
index 1c3b2b0ffb..db9d1e8ff0 100644
--- a/src/include/executor/instrument.h
+++ b/src/include/executor/instrument.h
@@ -38,7 +38,7 @@ typedef enum InstrumentOption
 	INSTRUMENT_TIMER = 1 << 0,	/* needs timer (and row counts) */
 	INSTRUMENT_BUFFERS = 1 << 1,	/* needs buffer usage */
 	INSTRUMENT_ROWS = 1 << 2,	/* needs row count */
-	INSTRUMENT_ALL = 0x7FFFFFFF
+	INSTRUMENT_ALL = INT32_MAX
 } InstrumentOption;
 
 typedef struct Instrumentation
diff --git a/src/include/nodes/parsenodes.h b/src/include/nodes/parsenodes.h
index ec0d0eaa4a..2893ceff18 100644
--- a/src/include/nodes/parsenodes.h
+++ b/src/include/nodes/parsenodes.h
@@ -587,7 +587,7 @@ typedef enum TableLikeOption
 	CREATE_TABLE_LIKE_INDEXES = 1 << 2,
 	CREATE_TABLE_LIKE_STORAGE = 1 << 3,
 	CREATE_TABLE_LIKE_COMMENTS = 1 << 4,
-	CREATE_TABLE_LIKE_ALL = 0x7FFFFFFF
+	CREATE_TABLE_LIKE_ALL = INT32_MAX
 } TableLikeOption;
 
 /*
diff --git a/src/include/pg_config_manual.h b/src/include/pg_config_manual.h
index 5cfc0ae1e8..d3e9888b7b 100644
--- a/src/include/pg_config_manual.h
+++ b/src/include/pg_config_manual.h
@@ -48,7 +48,7 @@
 /*
  * Set the upper and lower bounds of sequence values.
  */
-#define SEQ_MAXVALUE	INT64CONST(0x7FFFFFFFFFFFFFFF)
+#define SEQ_MAXVALUE	INT64_MAX
 #define SEQ_MINVALUE	(-SEQ_MAXVALUE)
 
 /*
@@ -185,7 +185,7 @@
  * the older rand() function, which is often different from --- and
  * considerably inferior to --- random().
  */
-#define MAX_RANDOM_VALUE  (0x7FFFFFFF)
+#define MAX_RANDOM_VALUE  INT32_MAX
 
 /*
  * On PPC machines, decide whether to use the mutex hint bit in LWARX
diff --git a/src/include/port/atomics.h b/src/include/port/atomics.h
index 89868b59c3..99173644a4 100644
--- a/src/include/port/atomics.h
+++ b/src/include/port/atomics.h
@@ -489,7 +489,7 @@ STATIC_IF_INLINE uint64
 pg_atomic_fetch_sub_u64(volatile pg_atomic_uint64 *ptr, int64 sub_)
 {
 	AssertPointerAlignment(ptr, 8);
-	Assert(sub_ != -INT64CONST(0x7FFFFFFFFFFFFFFF) - 1);
+	Assert(sub_ != INT64_MIN);
 	return pg_atomic_fetch_sub_u64_impl(ptr, sub_);
 }
 
@@ -518,7 +518,7 @@ STATIC_IF_INLINE uint64
 pg_atomic_sub_fetch_u64(volatile pg_atomic_uint64 *ptr, int64 sub_)
 {
 	AssertPointerAlignment(ptr, 8);
-	Assert(sub_ != -INT64CONST(0x7FFFFFFFFFFFFFFF) - 1);
+	Assert(sub_ != INT64_MIN);
 	return pg_atomic_sub_fetch_u64_impl(ptr, sub_);
 }
 
diff --git a/src/include/storage/predicate_internals.h b/src/include/storage/predicate_internals.h
index 2aaf58060d..8ecf923b1f 100644
--- a/src/include/storage/predicate_internals.h
+++ b/src/include/storage/predicate_internals.h
@@ -33,7 +33,7 @@ typedef uint64 SerCommitSeqNo;
  *	  at that point.  It's earlier than all normal sequence numbers,
  *	  and is only used by recovered prepared transactions
  */
-#define InvalidSerCommitSeqNo		((SerCommitSeqNo) UINT64CONST(0xFFFFFFFFFFFFFFFF))
+#define InvalidSerCommitSeqNo		((SerCommitSeqNo) UINT64_MAX)
 #define RecoverySerCommitSeqNo		((SerCommitSeqNo) 1)
 #define FirstNormalSerCommitSeqNo	((SerCommitSeqNo) 2)
 
diff --git a/src/include/utils/date.h b/src/include/utils/date.h
index b57f4bb3ea..f07011c385 100644
--- a/src/include/utils/date.h
+++ b/src/include/utils/date.h
@@ -35,11 +35,9 @@ typedef struct
 
 /*
  * Infinity and minus infinity must be the max and min values of DateADT.
- * We could use INT_MIN and INT_MAX here, but seems better to not assume that
- * int32 == int.
  */
-#define DATEVAL_NOBEGIN		((DateADT) (-0x7fffffff - 1))
-#define DATEVAL_NOEND		((DateADT) 0x7fffffff)
+#define DATEVAL_NOBEGIN		((DateADT) INT32_MIN)
+#define DATEVAL_NOEND		((DateADT) INT32_MAX)
 
 #define DATE_NOBEGIN(j)		((j) = DATEVAL_NOBEGIN)
 #define DATE_IS_NOBEGIN(j)	((j) == DATEVAL_NOBEGIN)