From be463a2da13734d5b104a5fc9c58e7bbb8908323 Mon Sep 17 00:00:00 2001
From: Aaron Patterson <aaron.patterson@gmail.com>
Date: Thu, 19 Nov 2015 14:44:49 -0800
Subject: [PATCH 1/2] add PQunescapeByteaConn for unescaping bytes given a
 connection

This commit adds an unescape method that takes a connection as a
parameter.  The connection may have settings on it (like allocators)
that are important to unescaping the string.
---
 src/interfaces/libpq/exports.txt |  1 +
 src/interfaces/libpq/fe-exec.c   | 21 +++++++++++++++++++--
 src/interfaces/libpq/libpq-fe.h  |  6 ++++--
 3 files changed, 24 insertions(+), 4 deletions(-)

diff --git a/src/interfaces/libpq/exports.txt b/src/interfaces/libpq/exports.txt
index d6a38d0df8..ba718f4071 100644
--- a/src/interfaces/libpq/exports.txt
+++ b/src/interfaces/libpq/exports.txt
@@ -172,3 +172,4 @@ PQsslAttribute            169
 PQsetErrorContextVisibility 170
 PQresultVerboseErrorMessage 171
 PQencryptPasswordConn     172
+PQunescapeByteaConn       173
diff --git a/src/interfaces/libpq/fe-exec.c b/src/interfaces/libpq/fe-exec.c
index e1e2d18e3a..464bdc635f 100644
--- a/src/interfaces/libpq/fe-exec.c
+++ b/src/interfaces/libpq/fe-exec.c
@@ -3651,8 +3651,9 @@ PQescapeBytea(const unsigned char *from, size_t from_length, size_t *to_length)
  *		\ooo == a byte whose value = ooo (ooo is an octal number)
  *		\x	 == x (x is any character not matched by the above transformations)
  */
-unsigned char *
-PQunescapeBytea(const unsigned char *strtext, size_t *retbuflen)
+static unsigned char *
+PQunescapeByteaInternal(PGconn *conn,
+					  const unsigned char *strtext, size_t *retbuflen)
 {
 	size_t		strtextlen,
 				buflen;
@@ -3762,3 +3763,19 @@ PQunescapeBytea(const unsigned char *strtext, size_t *retbuflen)
 	*retbuflen = buflen;
 	return tmpbuf;
 }
+
+unsigned char *
+PQunescapeByteaConn(PGconn *conn,
+				  const unsigned char *strtext, size_t *retbuflen)
+{
+	if (!conn)
+	    return NULL;
+
+	return PQunescapeByteaInternal(conn, strtext, retbuflen);
+}
+
+unsigned char *
+PQunescapeBytea(const unsigned char *strtext, size_t *retbuflen)
+{
+	return PQunescapeByteaInternal(NULL, strtext, retbuflen);
+}
diff --git a/src/interfaces/libpq/libpq-fe.h b/src/interfaces/libpq/libpq-fe.h
index 1d915e7915..7fce4b387e 100644
--- a/src/interfaces/libpq/libpq-fe.h
+++ b/src/interfaces/libpq/libpq-fe.h
@@ -527,13 +527,15 @@ extern char *PQescapeIdentifier(PGconn *conn, const char *str, size_t len);
 extern unsigned char *PQescapeByteaConn(PGconn *conn,
 				  const unsigned char *from, size_t from_length,
 				  size_t *to_length);
-extern unsigned char *PQunescapeBytea(const unsigned char *strtext,
-				size_t *retbuflen);
+extern unsigned char *PQunescapeByteaConn(PGconn *conn,
+                                  const unsigned char *strtext, size_t *retbuflen);
 
 /* These forms are deprecated! */
 extern size_t PQescapeString(char *to, const char *from, size_t length);
 extern unsigned char *PQescapeBytea(const unsigned char *from, size_t from_length,
 			  size_t *to_length);
+extern unsigned char *PQunescapeBytea(const unsigned char *strtext,
+				size_t *retbuflen);
 
 
 
-- 
2.11.0