libpq: Deprecate pg_int64.

Previously we used pg_int64 in three function prototypes in libpq.  It
was added by commit 461ef73f to expose the platform-dependent type used
for int64 in the C89 era.  As of commit 962da900 it is defined as
standard int64_t, and the dust seems to have settled.

Let's just use int64_t directly in these three client-facing functions
instead of (yet) another name.  We've required C99 and thus <stdint.h>
since PostgreSQL 12, C89 and C++98 compilers are long gone, and client
applications very likely use standard types for their own 64-bit needs.
This also cleans up the obscure placement of a new #include <stdint.h>
directive in postgres_ext.h, required for the new definition.  The
typedef was hiding in there for historical reasons, but it doesn't fit
postgres_ext.h's own description of its purpose and there is no evidence
of client applications including postgres_ext.h directly to see it.

Keep a typedef marked deprecated for backward compatibility, but move it
into libpq-fe.h where it was used.

Reviewed-by: Peter Eisentraut <peter@eisentraut.org>
Discussion: https://postgr.es/m/CA%2BhUKGKn_EkNNGMY5RzMcKP%2Ba6urT4JF%3DCPhw_zHtQwjvX6P2g%40mail.gmail.com

2 files changed, 4 insertions, 4 deletions

diff --git a/doc/src/sgml/libpq.sgml b/doc/src/sgml/libpq.sgml
index 8fa0515c6a0..b359fbff295 100644
--- a/doc/src/sgml/libpq.sgml
+++ b/doc/src/sgml/libpq.sgml
@@ -522,7 +522,7 @@ switch(PQstatus(conn))
        sequence described in the documentation of
        <xref linkend="libpq-PQconnectStartParams"/>.
 <synopsis>
-typedef pg_int64 pg_usec_time_t;
+typedef int64_t pg_usec_time_t;
 
 int PQsocketPoll(int sock, int forRead, int forWrite,
                  pg_usec_time_t end_time);
diff --git a/doc/src/sgml/lobj.sgml b/doc/src/sgml/lobj.sgml
index 083a83b5be8..79731c6553f 100644
--- a/doc/src/sgml/lobj.sgml
+++ b/doc/src/sgml/lobj.sgml
@@ -398,7 +398,7 @@ int lo_lseek(PGconn *conn, int fd, int offset, int whence);
      When dealing with large objects that might exceed 2GB in size,
      instead use
 <synopsis>
-pg_int64 lo_lseek64(PGconn *conn, int fd, pg_int64 offset, int whence);
+int64_t lo_lseek64(PGconn *conn, int fd, int64_t offset, int whence);
 </synopsis>
      This function has the same behavior
      as <function>lo_lseek</function>, but it can accept an
@@ -434,7 +434,7 @@ int lo_tell(PGconn *conn, int fd);
      When dealing with large objects that might exceed 2GB in size,
      instead use
 <synopsis>
-pg_int64 lo_tell64(PGconn *conn, int fd);
+int64_t lo_tell64(PGconn *conn, int fd);
 </synopsis>
      This function has the same behavior
      as <function>lo_tell</function>, but it can deliver a result larger
@@ -485,7 +485,7 @@ int lo_truncate(PGconn *conn, int fd, size_t len);
      When dealing with large objects that might exceed 2GB in size,
      instead use
 <synopsis>
-int lo_truncate64(PGconn *conn, int fd, pg_int64 len);
+int lo_truncate64(PGconn *conn, int fd, int64_t len);
 </synopsis>
      This function has the same
      behavior as <function>lo_truncate</function>, but it can accept a