libpq: Trace all messages received from the server

Not all messages that libpq received from the server would be sent
through our message tracing logic.  This commit tries to fix that by
introducing a new function pqParseDone which make it harder to forget
about doing so.

The messages that we now newly send through our tracing logic are:

- CopyData (received by COPY TO STDOUT)
- Authentication requests
- NegotiateProtocolVersion
- Some ErrorResponse messages during connection startup
- ReadyForQuery when received after a FunctionCall message

Author: Jelte Fennema-Nio <postgres@jeltef.nl>
Discussion: https://postgr.es/m/CAGECzQSoPHtZ4xe0raJ6FYSEiPPS+YWXBhOGo+Y1YecLgknF3g@mail.gmail.com

1 files changed, 21 insertions, 0 deletions

diff --git a/src/interfaces/libpq/fe-auth.c b/src/interfaces/libpq/fe-auth.c
index 4da07c1f986..5c8f404463f 100644
--- a/src/interfaces/libpq/fe-auth.c
+++ b/src/interfaces/libpq/fe-auth.c
@@ -94,6 +94,10 @@ pg_GSS_continue(PGconn *conn, int payloadlen)
 		ginbuf.value = NULL;
 	}
 
+	/* finished parsing, trace server-to-client message */
+	if (conn->Pfdebug)
+		pqTraceOutputMessage(conn, conn->inBuffer + conn->inStart, false);
+
 	/* Only try to acquire credentials if GSS delegation isn't disabled. */
 	if (!pg_GSS_have_cred_cache(&conn->gcred))
 		conn->gcred = GSS_C_NO_CREDENTIAL;
@@ -258,6 +262,10 @@ pg_SSPI_continue(PGconn *conn, int payloadlen)
 		InBuffers[0].BufferType = SECBUFFER_TOKEN;
 	}
 
+	/* finished parsing, trace server-to-client message */
+	if (conn->Pfdebug)
+		pqTraceOutputMessage(conn, conn->inBuffer + conn->inStart, false);
+
 	OutBuffers[0].pvBuffer = NULL;
 	OutBuffers[0].BufferType = SECBUFFER_TOKEN;
 	OutBuffers[0].cbBuffer = 0;
@@ -563,6 +571,10 @@ pg_SASL_init(PGconn *conn, int payloadlen)
 		}
 	}
 
+	/* finished parsing, trace server-to-client message */
+	if (conn->Pfdebug)
+		pqTraceOutputMessage(conn, conn->inBuffer + conn->inStart, false);
+
 	Assert(conn->sasl);
 
 	/*
@@ -651,6 +663,11 @@ pg_SASL_continue(PGconn *conn, int payloadlen, bool final)
 		free(challenge);
 		return STATUS_ERROR;
 	}
+
+	/* finished parsing, trace server-to-client message */
+	if (conn->Pfdebug)
+		pqTraceOutputMessage(conn, conn->inBuffer + conn->inStart, false);
+
 	/* For safety and convenience, ensure the buffer is NULL-terminated. */
 	challenge[payloadlen] = '\0';
 
@@ -716,6 +733,10 @@ pg_password_sendauth(PGconn *conn, const char *password, AuthRequest areq)
 			return STATUS_ERROR;	/* shouldn't happen */
 	}
 
+	/* finished parsing, trace server-to-client message */
+	if (conn->Pfdebug)
+		pqTraceOutputMessage(conn, conn->inBuffer + conn->inStart, false);
+
 	/* Encrypt the password if needed. */
 
 	switch (areq)