Move scanint8() to numutils.c

Move scanint8() to numutils.c and rename to pg_strtoint64().  We
already have a "16" and "32" version of that, and the code inside the
functions was aligned, so this move makes all three versions
consistent.  The API is also changed to no longer provide the errorOK
case.  Users that need the error checking can use strtoi64().

Reviewed-by: John Naylor <john.naylor@enterprisedb.com>
Discussion: https://www.postgresql.org/message-id/flat/b239564c-cad0-b23e-c57e-166d883cb97d@enterprisedb.com

4 files changed, 101 insertions, 95 deletions

diff --git a/src/backend/parser/parse_node.c b/src/backend/parser/parse_node.c
index 35db6b6c98..a49c985d36 100644
--- a/src/backend/parser/parse_node.c
+++ b/src/backend/parser/parse_node.c
@@ -26,7 +26,6 @@
 #include "parser/parse_relation.h"
 #include "parser/parsetree.h"
 #include "utils/builtins.h"
-#include "utils/int8.h"
 #include "utils/lsyscache.h"
 #include "utils/syscache.h"
 #include "utils/varbit.h"
@@ -353,7 +352,6 @@ make_const(ParseState *pstate, A_Const *aconst)
 {
 	Const	   *con;
 	Datum		val;
-	int64		val64;
 	Oid			typeid;
 	int			typelen;
 	bool		typebyval;
@@ -384,8 +382,15 @@ make_const(ParseState *pstate, A_Const *aconst)
 			break;
 
 		case T_Float:
+		{
 			/* could be an oversize integer as well as a float ... */
-			if (scanint8(aconst->val.fval.fval, true, &val64))
+
+			int64		val64;
+			char	   *endptr;
+
+			errno = 0;
+			val64 = strtoi64(aconst->val.fval.fval, &endptr, 10);
+			if (errno == 0 && *endptr == '\0')
 			{
 				/*
 				 * It might actually fit in int32. Probably only INT_MIN can
@@ -425,6 +430,7 @@ make_const(ParseState *pstate, A_Const *aconst)
 				typebyval = false;
 			}
 			break;
+		}
 
 		case T_Boolean:
 			val = BoolGetDatum(boolVal(&aconst->val));
diff --git a/src/backend/replication/pgoutput/pgoutput.c b/src/backend/replication/pgoutput/pgoutput.c
index 6df705f90f..4162bb8de7 100644
--- a/src/backend/replication/pgoutput/pgoutput.c
+++ b/src/backend/replication/pgoutput/pgoutput.c
@@ -21,7 +21,6 @@
 #include "replication/logicalproto.h"
 #include "replication/origin.h"
 #include "replication/pgoutput.h"
-#include "utils/int8.h"
 #include "utils/inval.h"
 #include "utils/lsyscache.h"
 #include "utils/memutils.h"
@@ -207,7 +206,8 @@ parse_output_parameters(List *options, PGOutputData *data)
 		/* Check each param, whether or not we recognize it */
 		if (strcmp(defel->defname, "proto_version") == 0)
 		{
-			int64		parsed;
+			unsigned long parsed;
+			char	   *endptr;
 
 			if (protocol_version_given)
 				ereport(ERROR,
@@ -215,12 +215,14 @@ parse_output_parameters(List *options, PGOutputData *data)
 						 errmsg("conflicting or redundant options")));
 			protocol_version_given = true;
 
-			if (!scanint8(strVal(defel->arg), true, &parsed))
+			errno = 0;
+			parsed = strtoul(strVal(defel->arg), &endptr, 10);
+			if (errno != 0 || *endptr != '\0')
 				ereport(ERROR,
 						(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 						 errmsg("invalid proto_version")));
 
-			if (parsed > PG_UINT32_MAX || parsed < 0)
+			if (parsed > PG_UINT32_MAX)
 				ereport(ERROR,
 						(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 						 errmsg("proto_version \"%s\" out of range",
diff --git a/src/backend/utils/adt/int8.c b/src/backend/utils/adt/int8.c
index ad19d154ff..4a87114a4f 100644
--- a/src/backend/utils/adt/int8.c
+++ b/src/backend/utils/adt/int8.c
@@ -24,7 +24,6 @@
 #include "nodes/supportnodes.h"
 #include "optimizer/optimizer.h"
 #include "utils/builtins.h"
-#include "utils/int8.h"
 
 
 typedef struct
@@ -45,99 +44,14 @@ typedef struct
  * Formatting and conversion routines.
  *---------------------------------------------------------*/
 
-/*
- * scanint8 --- try to parse a string into an int8.
- *
- * If errorOK is false, ereport a useful error message if the string is bad.
- * If errorOK is true, just return "false" for bad input.
- */
-bool
-scanint8(const char *str, bool errorOK, int64 *result)
-{
-	const char *ptr = str;
-	int64		tmp = 0;
-	bool		neg = false;
-
-	/*
-	 * Do our own scan, rather than relying on sscanf which might be broken
-	 * for long long.
-	 *
-	 * As INT64_MIN can't be stored as a positive 64 bit integer, accumulate
-	 * value as a negative number.
-	 */
-
-	/* skip leading spaces */
-	while (*ptr && isspace((unsigned char) *ptr))
-		ptr++;
-
-	/* handle sign */
-	if (*ptr == '-')
-	{
-		ptr++;
-		neg = true;
-	}
-	else if (*ptr == '+')
-		ptr++;
-
-	/* require at least one digit */
-	if (unlikely(!isdigit((unsigned char) *ptr)))
-		goto invalid_syntax;
-
-	/* process digits */
-	while (*ptr && isdigit((unsigned char) *ptr))
-	{
-		int8		digit = (*ptr++ - '0');
-
-		if (unlikely(pg_mul_s64_overflow(tmp, 10, &tmp)) ||
-			unlikely(pg_sub_s64_overflow(tmp, digit, &tmp)))
-			goto out_of_range;
-	}
-
-	/* allow trailing whitespace, but not other trailing chars */
-	while (*ptr != '\0' && isspace((unsigned char) *ptr))
-		ptr++;
-
-	if (unlikely(*ptr != '\0'))
-		goto invalid_syntax;
-
-	if (!neg)
-	{
-		/* could fail if input is most negative number */
-		if (unlikely(tmp == PG_INT64_MIN))
-			goto out_of_range;
-		tmp = -tmp;
-	}
-
-	*result = tmp;
-	return true;
-
-out_of_range:
-	if (!errorOK)
-		ereport(ERROR,
-				(errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
-				 errmsg("value \"%s\" is out of range for type %s",
-						str, "bigint")));
-	return false;
-
-invalid_syntax:
-	if (!errorOK)
-		ereport(ERROR,
-				(errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
-				 errmsg("invalid input syntax for type %s: \"%s\"",
-						"bigint", str)));
-	return false;
-}
-
 /* int8in()
  */
 Datum
 int8in(PG_FUNCTION_ARGS)
 {
-	char	   *str = PG_GETARG_CSTRING(0);
-	int64		result;
+	char	   *num = PG_GETARG_CSTRING(0);
 
-	(void) scanint8(str, false, &result);
-	PG_RETURN_INT64(result);
+	PG_RETURN_INT64(pg_strtoint64(num));
 }
 
 
diff --git a/src/backend/utils/adt/numutils.c b/src/backend/utils/adt/numutils.c
index 898a9e3f9a..e82d23a325 100644
--- a/src/backend/utils/adt/numutils.c
+++ b/src/backend/utils/adt/numutils.c
@@ -326,6 +326,90 @@ invalid_syntax:
 }
 
 /*
+ * Convert input string to a signed 64 bit integer.
+ *
+ * Allows any number of leading or trailing whitespace characters. Will throw
+ * ereport() upon bad input format or overflow.
+ *
+ * NB: Accumulate input as a negative number, to deal with two's complement
+ * representation of the most negative number, which can't be represented as a
+ * positive number.
+ */
+int64
+pg_strtoint64(const char *s)
+{
+	const char *ptr = s;
+	int64		tmp = 0;
+	bool		neg = false;
+
+	/*
+	 * Do our own scan, rather than relying on sscanf which might be broken
+	 * for long long.
+	 *
+	 * As INT64_MIN can't be stored as a positive 64 bit integer, accumulate
+	 * value as a negative number.
+	 */
+
+	/* skip leading spaces */
+	while (*ptr && isspace((unsigned char) *ptr))
+		ptr++;
+
+	/* handle sign */
+	if (*ptr == '-')
+	{
+		ptr++;
+		neg = true;
+	}
+	else if (*ptr == '+')
+		ptr++;
+
+	/* require at least one digit */
+	if (unlikely(!isdigit((unsigned char) *ptr)))
+		goto invalid_syntax;
+
+	/* process digits */
+	while (*ptr && isdigit((unsigned char) *ptr))
+	{
+		int8		digit = (*ptr++ - '0');
+
+		if (unlikely(pg_mul_s64_overflow(tmp, 10, &tmp)) ||
+			unlikely(pg_sub_s64_overflow(tmp, digit, &tmp)))
+			goto out_of_range;
+	}
+
+	/* allow trailing whitespace, but not other trailing chars */
+	while (*ptr != '\0' && isspace((unsigned char) *ptr))
+		ptr++;
+
+	if (unlikely(*ptr != '\0'))
+		goto invalid_syntax;
+
+	if (!neg)
+	{
+		/* could fail if input is most negative number */
+		if (unlikely(tmp == PG_INT64_MIN))
+			goto out_of_range;
+		tmp = -tmp;
+	}
+
+	return tmp;
+
+out_of_range:
+	ereport(ERROR,
+			(errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
+			 errmsg("value \"%s\" is out of range for type %s",
+					s, "bigint")));
+
+invalid_syntax:
+	ereport(ERROR,
+			(errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
+			 errmsg("invalid input syntax for type %s: \"%s\"",
+					"bigint", s)));
+
+	return 0;					/* keep compiler quiet */
+}
+
+/*
  * pg_itoa: converts a signed 16-bit integer to its string representation
  * and returns strlen(a).
  *