0001-libpq-Remove-redundant-null-pointer-checks-before-fr.patch

From f7a10c1fca10c76b89dbf402ad9418ed8f0675d7 Mon Sep 17 00:00:00 2001
From: Peter Eisentraut <peter@eisentraut.org>
Date: Thu, 16 Jun 2022 21:50:56 +0200
Subject: [PATCH] libpq: Remove redundant null pointer checks before free()

---
 src/interfaces/libpq/fe-auth-scram.c    |  33 ++--
 src/interfaces/libpq/fe-auth.c          |  18 +-
 src/interfaces/libpq/fe-connect.c       | 211 ++++++++----------------
 src/interfaces/libpq/fe-exec.c          |   6 +-
 src/interfaces/libpq/fe-print.c         |  23 +--
 src/interfaces/libpq/fe-secure-common.c |   3 +-
 6 files changed, 97 insertions(+), 197 deletions(-)

diff --git a/src/interfaces/libpq/fe-auth-scram.c b/src/interfaces/libpq/fe-auth-scram.c
index e616200704..5012806fa5 100644
--- a/src/interfaces/libpq/fe-auth-scram.c
+++ b/src/interfaces/libpq/fe-auth-scram.c
@@ -174,30 +174,21 @@ scram_free(void *opaq)
 {
 	fe_scram_state *state = (fe_scram_state *) opaq;
 
-	if (state->password)
-		free(state->password);
-	if (state->sasl_mechanism)
-		free(state->sasl_mechanism);
+	free(state->password);
+	free(state->sasl_mechanism);
 
 	/* client messages */
-	if (state->client_nonce)
-		free(state->client_nonce);
-	if (state->client_first_message_bare)
-		free(state->client_first_message_bare);
-	if (state->client_final_message_without_proof)
-		free(state->client_final_message_without_proof);
+	free(state->client_nonce);
+	free(state->client_first_message_bare);
+	free(state->client_final_message_without_proof);
 
 	/* first message from server */
-	if (state->server_first_message)
-		free(state->server_first_message);
-	if (state->salt)
-		free(state->salt);
-	if (state->nonce)
-		free(state->nonce);
+	free(state->server_first_message);
+	free(state->salt);
+	free(state->nonce);
 
 	/* final message from server */
-	if (state->server_final_message)
-		free(state->server_final_message);
+	free(state->server_final_message);
 
 	free(state);
 }
@@ -941,8 +932,7 @@ pg_fe_scram_build_secret(const char *password, const char **errstr)
 	if (!pg_strong_random(saltbuf, SCRAM_DEFAULT_SALT_LEN))
 	{
 		*errstr = _("failed to generate random salt");
-		if (prep_password)
-			free(prep_password);
+		free(prep_password);
 		return NULL;
 	}
 
@@ -950,8 +940,7 @@ pg_fe_scram_build_secret(const char *password, const char **errstr)
 								SCRAM_DEFAULT_ITERATIONS, password,
 								errstr);
 
-	if (prep_password)
-		free(prep_password);
+	free(prep_password);
 
 	return result;
 }
diff --git a/src/interfaces/libpq/fe-auth.c b/src/interfaces/libpq/fe-auth.c
index 0a072a36dc..49a1c626f6 100644
--- a/src/interfaces/libpq/fe-auth.c
+++ b/src/interfaces/libpq/fe-auth.c
@@ -107,8 +107,7 @@ pg_GSS_continue(PGconn *conn, int payloadlen)
 									NULL,
 									NULL);
 
-	if (ginbuf.value)
-		free(ginbuf.value);
+	free(ginbuf.value);
 
 	if (goutbuf.length != 0)
 	{
@@ -270,8 +269,7 @@ pg_SSPI_continue(PGconn *conn, int payloadlen)
 								  NULL);
 
 	/* we don't need the input anymore */
-	if (inputbuf)
-		free(inputbuf);
+	free(inputbuf);
 
 	if (r != SEC_E_OK && r != SEC_I_CONTINUE_NEEDED)
 	{
@@ -604,21 +602,18 @@ pg_SASL_init(PGconn *conn, int payloadlen)
 		goto error;
 
 	termPQExpBuffer(&mechanism_buf);
-	if (initialresponse)
-		free(initialresponse);
+	free(initialresponse);
 
 	return STATUS_OK;
 
 error:
 	termPQExpBuffer(&mechanism_buf);
-	if (initialresponse)
-		free(initialresponse);
+	free(initialresponse);
 	return STATUS_ERROR;
 
 oom_error:
 	termPQExpBuffer(&mechanism_buf);
-	if (initialresponse)
-		free(initialresponse);
+	free(initialresponse);
 	appendPQExpBufferStr(&conn->errorMessage,
 						 libpq_gettext("out of memory\n"));
 	return STATUS_ERROR;
@@ -831,8 +826,7 @@ pg_password_sendauth(PGconn *conn, const char *password, AuthRequest areq)
 			return STATUS_ERROR;
 	}
 	ret = pqPacketSend(conn, 'p', pwd_to_send, strlen(pwd_to_send) + 1);
-	if (crypt_pwd)
-		free(crypt_pwd);
+	free(crypt_pwd);
 	return ret;
 }
 
diff --git a/src/interfaces/libpq/fe-connect.c b/src/interfaces/libpq/fe-connect.c
index 6e936bbff3..057c9da0ed 100644
--- a/src/interfaces/libpq/fe-connect.c
+++ b/src/interfaces/libpq/fe-connect.c
@@ -540,8 +540,7 @@ pqFreeCommandQueue(PGcmdQueueEntry *queue)
 		PGcmdQueueEntry *cur = queue;
 
 		queue = cur->next;
-		if (cur->query)
-			free(cur->query);
+		free(cur->query);
 		free(cur);
 	}
 }
@@ -593,8 +592,7 @@ pqDropServerData(PGconn *conn)
 	conn->sversion = 0;
 
 	/* Drop large-object lookup data */
-	if (conn->lobjfuncs)
-		free(conn->lobjfuncs);
+	free(conn->lobjfuncs);
 	conn->lobjfuncs = NULL;
 
 	/* Reset assorted other per-connection state */
@@ -602,8 +600,7 @@ pqDropServerData(PGconn *conn)
 	conn->auth_req_received = false;
 	conn->password_needed = false;
 	conn->write_failed = false;
-	if (conn->write_err_msg)
-		free(conn->write_err_msg);
+	free(conn->write_err_msg);
 	conn->write_err_msg = NULL;
 	conn->be_pid = 0;
 	conn->be_key = 0;
@@ -898,8 +895,7 @@ fillPGconn(PGconn *conn, PQconninfoOption *connOptions)
 			{
 				char	  **connmember = (char **) ((char *) conn + option->connofs);
 
-				if (*connmember)
-					free(*connmember);
+				free(*connmember);
 				*connmember = strdup(tmp);
 				if (*connmember == NULL)
 				{
@@ -1113,8 +1109,7 @@ connectOptions2(PGconn *conn)
 		}
 		else
 		{
-			if (ch->host)
-				free(ch->host);
+			free(ch->host);
 
 			/*
 			 * This bit selects the default host location.  If you change
@@ -1186,8 +1181,7 @@ connectOptions2(PGconn *conn)
 	 */
 	if (conn->pguser == NULL || conn->pguser[0] == '\0')
 	{
-		if (conn->pguser)
-			free(conn->pguser);
+		free(conn->pguser);
 		conn->pguser = pg_fe_getauthname(&conn->errorMessage);
 		if (!conn->pguser)
 		{
@@ -1201,8 +1195,7 @@ connectOptions2(PGconn *conn)
 	 */
 	if (conn->dbName == NULL || conn->dbName[0] == '\0')
 	{
-		if (conn->dbName)
-			free(conn->dbName);
+		free(conn->dbName);
 		conn->dbName = strdup(conn->pguser);
 		if (!conn->dbName)
 			goto oom_error;
@@ -1221,8 +1214,7 @@ connectOptions2(PGconn *conn)
 
 			if (pqGetHomeDirectory(homedir, sizeof(homedir)))
 			{
-				if (conn->pgpassfile)
-					free(conn->pgpassfile);
+				free(conn->pgpassfile);
 				conn->pgpassfile = malloc(MAXPGPATH);
 				if (!conn->pgpassfile)
 					goto oom_error;
@@ -1548,8 +1540,7 @@ PQsetdbLogin(const char *pghost, const char *pgport, const char *pgoptions,
 		/* Insert dbName parameter value into struct */
 		if (dbName && dbName[0] != '\0')
 		{
-			if (conn->dbName)
-				free(conn->dbName);
+			free(conn->dbName);
 			conn->dbName = strdup(dbName);
 			if (!conn->dbName)
 				goto oom_error;
@@ -1562,8 +1553,7 @@ PQsetdbLogin(const char *pghost, const char *pgport, const char *pgoptions,
 	 */
 	if (pghost && pghost[0] != '\0')
 	{
-		if (conn->pghost)
-			free(conn->pghost);
+		free(conn->pghost);
 		conn->pghost = strdup(pghost);
 		if (!conn->pghost)
 			goto oom_error;
@@ -1571,8 +1561,7 @@ PQsetdbLogin(const char *pghost, const char *pgport, const char *pgoptions,
 
 	if (pgport && pgport[0] != '\0')
 	{
-		if (conn->pgport)
-			free(conn->pgport);
+		free(conn->pgport);
 		conn->pgport = strdup(pgport);
 		if (!conn->pgport)
 			goto oom_error;
@@ -1580,8 +1569,7 @@ PQsetdbLogin(const char *pghost, const char *pgport, const char *pgoptions,
 
 	if (pgoptions && pgoptions[0] != '\0')
 	{
-		if (conn->pgoptions)
-			free(conn->pgoptions);
+		free(conn->pgoptions);
 		conn->pgoptions = strdup(pgoptions);
 		if (!conn->pgoptions)
 			goto oom_error;
@@ -1589,8 +1577,7 @@ PQsetdbLogin(const char *pghost, const char *pgport, const char *pgoptions,
 
 	if (login && login[0] != '\0')
 	{
-		if (conn->pguser)
-			free(conn->pguser);
+		free(conn->pguser);
 		conn->pguser = strdup(login);
 		if (!conn->pguser)
 			goto oom_error;
@@ -1598,8 +1585,7 @@ PQsetdbLogin(const char *pghost, const char *pgport, const char *pgoptions,
 
 	if (pwd && pwd[0] != '\0')
 	{
-		if (conn->pgpass)
-			free(conn->pgpass);
+		free(conn->pgpass);
 		conn->pgpass = strdup(pwd);
 		if (!conn->pgpass)
 			goto oom_error;
@@ -4044,10 +4030,8 @@ makeEmptyPGconn(void)
 static void
 freePGconn(PGconn *conn)
 {
-	int			i;
-
 	/* let any event procs clean up their state data */
-	for (i = 0; i < conn->nEvents; i++)
+	for (int i = 0; i < conn->nEvents; i++)
 	{
 		PGEventConnDestroy evt;
 
@@ -4058,114 +4042,69 @@ freePGconn(PGconn *conn)
 	}
 
 	/* clean up pg_conn_host structures */
-	if (conn->connhost != NULL)
+	for (int i = 0; i < conn->nconnhost; ++i)
 	{
-		for (i = 0; i < conn->nconnhost; ++i)
+		free(conn->connhost[i].host);
+		free(conn->connhost[i].hostaddr);
+		free(conn->connhost[i].port);
+		if (conn->connhost[i].password != NULL)
 		{
-			if (conn->connhost[i].host != NULL)
-				free(conn->connhost[i].host);
-			if (conn->connhost[i].hostaddr != NULL)
-				free(conn->connhost[i].hostaddr);
-			if (conn->connhost[i].port != NULL)
-				free(conn->connhost[i].port);
-			if (conn->connhost[i].password != NULL)
-			{
-				explicit_bzero(conn->connhost[i].password, strlen(conn->connhost[i].password));
-				free(conn->connhost[i].password);
-			}
+			explicit_bzero(conn->connhost[i].password, strlen(conn->connhost[i].password));
+			free(conn->connhost[i].password);
 		}
-		free(conn->connhost);
 	}
-
-	if (conn->client_encoding_initial)
-		free(conn->client_encoding_initial);
-	if (conn->events)
-		free(conn->events);
-	if (conn->pghost)
-		free(conn->pghost);
-	if (conn->pghostaddr)
-		free(conn->pghostaddr);
-	if (conn->pgport)
-		free(conn->pgport);
-	if (conn->connect_timeout)
-		free(conn->connect_timeout);
-	if (conn->pgtcp_user_timeout)
-		free(conn->pgtcp_user_timeout);
-	if (conn->pgoptions)
-		free(conn->pgoptions);
-	if (conn->appname)
-		free(conn->appname);
-	if (conn->fbappname)
-		free(conn->fbappname);
-	if (conn->dbName)
-		free(conn->dbName);
-	if (conn->replication)
-		free(conn->replication);
-	if (conn->pguser)
-		free(conn->pguser);
+	free(conn->connhost);
+
+	free(conn->client_encoding_initial);
+	free(conn->events);
+	free(conn->pghost);
+	free(conn->pghostaddr);
+	free(conn->pgport);
+	free(conn->connect_timeout);
+	free(conn->pgtcp_user_timeout);
+	free(conn->pgoptions);
+	free(conn->appname);
+	free(conn->fbappname);
+	free(conn->dbName);
+	free(conn->replication);
+	free(conn->pguser);
 	if (conn->pgpass)
 	{
 		explicit_bzero(conn->pgpass, strlen(conn->pgpass));
 		free(conn->pgpass);
 	}
-	if (conn->pgpassfile)
-		free(conn->pgpassfile);
-	if (conn->channel_binding)
-		free(conn->channel_binding);
-	if (conn->keepalives)
-		free(conn->keepalives);
-	if (conn->keepalives_idle)
-		free(conn->keepalives_idle);
-	if (conn->keepalives_interval)
-		free(conn->keepalives_interval);
-	if (conn->keepalives_count)
-		free(conn->keepalives_count);
-	if (conn->sslmode)
-		free(conn->sslmode);
-	if (conn->sslcert)
-		free(conn->sslcert);
-	if (conn->sslkey)
-		free(conn->sslkey);
+	free(conn->pgpassfile);
+	free(conn->channel_binding);
+	free(conn->keepalives);
+	free(conn->keepalives_idle);
+	free(conn->keepalives_interval);
+	free(conn->keepalives_count);
+	free(conn->sslmode);
+	free(conn->sslcert);
+	free(conn->sslkey);
 	if (conn->sslpassword)
 	{
 		explicit_bzero(conn->sslpassword, strlen(conn->sslpassword));
 		free(conn->sslpassword);
 	}
-	if (conn->sslrootcert)
-		free(conn->sslrootcert);
-	if (conn->sslcrl)
-		free(conn->sslcrl);
-	if (conn->sslcrldir)
-		free(conn->sslcrldir);
-	if (conn->sslcompression)
-		free(conn->sslcompression);
-	if (conn->sslsni)
-		free(conn->sslsni);
-	if (conn->requirepeer)
-		free(conn->requirepeer);
-	if (conn->ssl_min_protocol_version)
-		free(conn->ssl_min_protocol_version);
-	if (conn->ssl_max_protocol_version)
-		free(conn->ssl_max_protocol_version);
-	if (conn->gssencmode)
-		free(conn->gssencmode);
-	if (conn->krbsrvname)
-		free(conn->krbsrvname);
-	if (conn->gsslib)
-		free(conn->gsslib);
-	if (conn->connip)
-		free(conn->connip);
+	free(conn->sslrootcert);
+	free(conn->sslcrl);
+	free(conn->sslcrldir);
+	free(conn->sslcompression);
+	free(conn->sslsni);
+	free(conn->requirepeer);
+	free(conn->ssl_min_protocol_version);
+	free(conn->ssl_max_protocol_version);
+	free(conn->gssencmode);
+	free(conn->krbsrvname);
+	free(conn->gsslib);
+	free(conn->connip);
 	/* Note that conn->Pfdebug is not ours to close or free */
-	if (conn->write_err_msg)
-		free(conn->write_err_msg);
-	if (conn->inBuffer)
-		free(conn->inBuffer);
-	if (conn->outBuffer)
-		free(conn->outBuffer);
-	if (conn->rowBuf)
-		free(conn->rowBuf);
-	if (conn->target_session_attrs)
-		free(conn->target_session_attrs);
+	free(conn->write_err_msg);
+	free(conn->inBuffer);
+	free(conn->outBuffer);
+	free(conn->rowBuf);
+	free(conn->target_session_attrs);
 	termPQExpBuffer(&conn->errorMessage);
 	termPQExpBuffer(&conn->workBuffer);
 
@@ -4433,8 +4372,7 @@ PQgetCancel(PGconn *conn)
 void
 PQfreeCancel(PGcancel *cancel)
 {
-	if (cancel)
-		free(cancel);
+	free(cancel);
 }
 
 
@@ -5883,8 +5821,7 @@ conninfo_array_parse(const char *const *keywords, const char *const *values,
 						{
 							if (strcmp(options[k].keyword, str_option->keyword) == 0)
 							{
-								if (options[k].val)
-									free(options[k].val);
+								free(options[k].val);
 								options[k].val = strdup(str_option->val);
 								if (!options[k].val)
 								{
@@ -5912,8 +5849,7 @@ conninfo_array_parse(const char *const *keywords, const char *const *values,
 				/*
 				 * Store the value, overriding previous settings
 				 */
-				if (option->val)
-					free(option->val);
+				free(option->val);
 				option->val = strdup(pvalue);
 				if (!option->val)
 				{
@@ -6344,8 +6280,7 @@ conninfo_uri_parse_options(PQconninfoOption *options, const char *uri,
 cleanup:
 	termPQExpBuffer(&hostbuf);
 	termPQExpBuffer(&portbuf);
-	if (buf)
-		free(buf);
+	free(buf);
 	return retval;
 }
 
@@ -6655,8 +6590,7 @@ conninfo_storeval(PQconninfoOption *connOptions,
 		}
 	}
 
-	if (option->val)
-		free(option->val);
+	free(option->val);
 	option->val = value_copy;
 
 	return option;
@@ -6735,16 +6669,11 @@ PQconninfo(PGconn *conn)
 void
 PQconninfoFree(PQconninfoOption *connOptions)
 {
-	PQconninfoOption *option;
-
 	if (connOptions == NULL)
 		return;
 
-	for (option = connOptions; option->keyword != NULL; option++)
-	{
-		if (option->val != NULL)
-			free(option->val);
-	}
+	for (PQconninfoOption *option = connOptions; option->keyword != NULL; option++)
+		free(option->val);
 	free(connOptions);
 }
 
diff --git a/src/interfaces/libpq/fe-exec.c b/src/interfaces/libpq/fe-exec.c
index 919cf5741d..1750d647a8 100644
--- a/src/interfaces/libpq/fe-exec.c
+++ b/src/interfaces/libpq/fe-exec.c
@@ -742,8 +742,7 @@ PQclear(PGresult *res)
 		free(res->events[i].name);
 	}
 
-	if (res->events)
-		free(res->events);
+	free(res->events);
 
 	/* Free all the subsidiary blocks */
 	while ((block = res->curBlock) != NULL)
@@ -753,8 +752,7 @@ PQclear(PGresult *res)
 	}
 
 	/* Free the top-level tuple pointer array */
-	if (res->tuples)
-		free(res->tuples);
+	free(res->tuples);
 
 	/* zero out the pointer fields to catch programming errors */
 	res->attDescs = NULL;
diff --git a/src/interfaces/libpq/fe-print.c b/src/interfaces/libpq/fe-print.c
index 82fc592f06..783cd9b756 100644
--- a/src/interfaces/libpq/fe-print.c
+++ b/src/interfaces/libpq/fe-print.c
@@ -303,26 +303,19 @@ PQprint(FILE *fout, const PGresult *res, const PQprintOpt *po)
 			fputs("</table>\n", fout);
 
 exit:
-		if (fieldMax)
-			free(fieldMax);
-		if (fieldNotNum)
-			free(fieldNotNum);
-		if (border)
-			free(border);
+		free(fieldMax);
+		free(fieldNotNum);
+		free(border);
 		if (fields)
 		{
 			/* if calloc succeeded, this shouldn't overflow size_t */
 			size_t		numfields = ((size_t) nTups + 1) * (size_t) nFields;
 
 			while (numfields-- > 0)
-			{
-				if (fields[numfields])
-					free(fields[numfields]);
-			}
+				free(fields[numfields]);
 			free(fields);
 		}
-		if (fieldNames)
-			free((void *) fieldNames);
+		free(fieldNames);
 		if (usePipe)
 		{
 #ifdef WIN32
@@ -679,8 +672,7 @@ PQdisplayTuples(const PGresult *res,
 
 	fflush(fp);
 
-	if (fLength)
-		free(fLength);
+	free(fLength);
 }
 
 
@@ -763,8 +755,7 @@ PQprintTuples(const PGresult *res,
 		}
 	}
 
-	if (tborder)
-		free(tborder);
+	free(tborder);
 }
 
 
diff --git a/src/interfaces/libpq/fe-secure-common.c b/src/interfaces/libpq/fe-secure-common.c
index 8046fcd884..cc8a2b8593 100644
--- a/src/interfaces/libpq/fe-secure-common.c
+++ b/src/interfaces/libpq/fe-secure-common.c
@@ -309,8 +309,7 @@ pq_verify_peer_name_matches_certificate(PGconn *conn)
 	}
 
 	/* clean up */
-	if (first_name)
-		free(first_name);
+	free(first_name);
 
 	return (rc == 1);
 }
-- 
2.36.1