--- sql/pgsql/parser3pgsql.C	2008/06/26 15:49:40	1.30
+++ sql/pgsql/parser3pgsql.C	2021/11/03 15:14:05	1.48
@@ -1,13 +1,12 @@
 /** @file
 	Parser PgSQL driver.
 
-	Copyright(c) 2001, 2003 ArtLebedev Group (http://www.artlebedev.com)
+	Copyright (c) 2001-2019 Art. Lebedev Studio (http://www.artlebedev.com)
 
 	Author: Alexandr Petrosian <paf@design.ru> (http://paf.design.ru)
 
 	2007.10.25 using PgSQL 8.1.5
 */
-static const char *RCSId="$Id: parser3pgsql.C,v 1.30 2008/06/26 15:49:40 misha Exp $"; 
 
 #include "config_includes.h"
 
@@ -16,17 +15,32 @@ static const char *RCSId="$Id: parser3pg
 #include <libpq-fe.h>
 #include <libpq/libpq-fs.h>
 
-// OIDOID from catalog/pg_type.h
+volatile const char * IDENT_PARSER3PGSQL_C="$Id: parser3pgsql.C,v 1.48 2021/11/03 15:14:05 moko Exp $" IDENT_PA_SQL_DRIVER_H;
+
+// from catalog/pg_type.h
+#define BOOLOID			16
+#define INT8OID			20
+#define INT2OID			21
+#define INT4OID			23
 #define OIDOID			26
+#define FLOAT4OID		700
+#define FLOAT8OID		701
+#define DATEOID			1082
+#define TIMEOID			1083
+#define TIMESTAMPOID	1114
+#define TIMESTAMPTZOID	1184
+#define TIMETZOID		1266
+#define NUMERICOID		1700
+
 // LO_BUFSIZE from interfaces\libpq\fe-lobj.c = 8192 (0x2000)
 // actually writing chunks of that size failed, reduced it twice
 #define LO_BUFSIZE		  0x1000
-// from postgres_ext.h
-//#define InvalidOid		((Oid) 0)
 
 
 #include "ltdl.h"
 
+#define MAX_COLS 500
+
 #define MAX_STRING 0x400
 #define MAX_NUMBER 20
 
@@ -64,7 +78,7 @@ static char* rsplit(char* string, char d
 			return v+1;
 		}
 	}
-	return NULL;	
+	return NULL;
 }
 
 static void toupper_str(char *out, const char *in, size_t size){
@@ -72,12 +86,20 @@ static void toupper_str(char *out, const
 		*out++=(char)toupper(*in++);
 }
 
+inline static const char* strdup(SQL_Driver_services& services, char* str, size_t length) {
+	char *strm=(char*)services.malloc_atomic(length+1);
+	memcpy(strm, str, length);
+	strm[length]=0;
+	return (const char*)strm;
+}
+
 struct Connection {
 	SQL_Driver_services* services;
 
 	PGconn *conn;
 	const char* client_charset;
 	bool autocommit;
+	bool standard_conforming_strings;
 };
 
 /**
@@ -94,15 +116,14 @@ public:
 
 	/// initialize driver by loading sql dynamic link library
 	const char *initialize(char *dlopen_file_spec){
-		return dlopen_file_spec?
-			dlink(dlopen_file_spec):"client library column is empty";
+		return dlopen_file_spec ? dlink(dlopen_file_spec) : "client library column is empty";
 	}
 
 	#define throwPQerror connection.services->_throw(PQerrorMessage(connection.conn))
 	#define PQclear_throw(msg) { \
 			PQclear(res); \
 			connection.services->_throw(msg); \
-		}						
+		}
 	#define PQclear_throwPQerror PQclear_throw(PQerrorMessage(connection.conn))
 
 	/**	connect
@@ -111,14 +132,10 @@ public:
 			ClientCharset=charset&	// transcode by parser
 			charset=value&			// transcode by server with 'SET CLIENT_ENCODING=value'
 			datestyle=value&		// 'SET DATESTYLE=value' available values are: ISO|SQL|Postgres|European|US|German [default=ISO]
-			autocommit=1&
-			WithoutDefaultTransaction=1	// == autocommit=0
+			autocommit=0&			// 1 -- each statement is commited automatically, only when with_default_transaction enabled
+			standard_conforming_strings=1&	// 0 -- escape \ char that could be needed for old servers
 	*/
-	void connect(
-				char* url, 
-				SQL_Driver_services& services, 
-				void** connection_ref ///< output: Connection*
-	){
+	void connect(char* url, SQL_Driver_services& services, void** connection_ref /* < output: Connection* */){
 		char* user=url;
 		char* host=rsplit(user, '@');
 		char* db=lsplit(host, '/');
@@ -131,13 +148,14 @@ public:
 		char* datestyle=0;
 
 		Connection& connection=*(Connection *)services.malloc(sizeof(Connection));
+
 		*connection_ref=&connection;
 		connection.services=&services;
-		connection.client_charset=0;	
+		connection.client_charset=0;
 		connection.autocommit=true;
-		connection.conn=PQsetdbLogin(
-			(host&&strcasecmp(host, "local")==0)?NULL/* local Unix domain socket */:host, port, 
-			NULL, NULL, db, user, pwd);
+		connection.standard_conforming_strings=true;
+
+		connection.conn=PQsetdbLogin( (host && strcasecmp(host, "local") == 0) ? NULL /* local Unix domain socket */ : host, port, NULL, NULL, db, user, pwd);
 
 		if(!connection.conn)
 			services._throw("PQsetdbLogin failed");
@@ -149,19 +167,19 @@ public:
 			if(char *key=lsplit(&options, '&')){
 				if(*key){
 					if(char *value=lsplit(key, '=')){
-						if(strcmp(key, "ClientCharset")==0){ // transcoding with parser
+						if(strcmp(key, "ClientCharset")==0){
 							toupper_str(value, value, strlen(value));
 							connection.client_charset=value;
-						} else if(strcasecmp(key, "charset")==0){ // transcoding with server
+						} else if(strcasecmp(key, "charset")==0){
 							charset=value;
 						} else if(strcasecmp(key, "datestyle")==0){
 							datestyle=value;
 						} else if(strcasecmp(key, "autocommit")==0){
 							if(atoi(value)==0)
 								connection.autocommit=false;
-						} else if(strcmp(key, "WithoutDefaultTransaction")==0){ // backward, use autocommit=0
-							if(atoi(value)==1)
-								connection.autocommit=false;
+						} else if(strcasecmp(key, "standard_conforming_strings")==0){
+							if(atoi(value)==0)
+								connection.standard_conforming_strings=false;
 						} else
 							services._throw("unknown connect option" /*key*/);
 					} else 
@@ -171,20 +189,21 @@ public:
 		}
 
 		if(charset){
-			char statement[MAX_STRING]="SET CLIENT_ENCODING=";
+			char statement[MAX_STRING+1]="SET CLIENT_ENCODING=";
 			strncat(statement, charset, MAX_STRING);
 
 			_execute_cmd(connection, statement);
 		}
 
 		if(datestyle){
-			char statement[MAX_STRING]="SET DATESTYLE=";
+			char statement[MAX_STRING+1]="SET DATESTYLE=";
 			strncat(statement, datestyle, MAX_STRING);
 
 			_execute_cmd(connection, statement);
 		}
 
-		_begin_transaction(connection);
+		if(!connection.autocommit)
+			_execute_cmd(connection, "set AUTOCOMMIT off");
 	}
 
 	void disconnect(void *aconnection){
@@ -195,18 +214,14 @@ public:
 
 	void commit(void *aconnection){
 		Connection& connection=*static_cast<Connection*>(aconnection);
-		if(connection.autocommit){
+		if(!connection.autocommit)
 			_execute_cmd(connection, "COMMIT");
-		}
-		_begin_transaction(connection);
 	}
 
 	void rollback(void *aconnection){
 		Connection& connection=*static_cast<Connection*>(aconnection);
-		if(connection.autocommit){
+		if(!connection.autocommit)
 			_execute_cmd(connection, "ROLLBACK");
-		}
-		_begin_transaction(connection);
 	}
 
 	bool ping(void *aconnection) {
@@ -214,27 +229,69 @@ public:
 		return PQstatus(connection.conn)==CONNECTION_OK;
 	}
 
-	const char* quote(void *aconnection, const char *from, unsigned int length){
+	// charset here is services.request_charset(), not connection.client_charset
+	// thus we can't use the sql server quoting support
+	const char* quote(void *aconnection, const char *str, unsigned int length){
 		Connection& connection=*static_cast<Connection*>(aconnection);
 
-		char *result=(char*)connection.services->malloc_atomic(length*2+1);
-		int err=0;
-		PQescapeStringConn(connection.conn, result, from, length, &err);
+		const char* from;
+		const char* from_end=str+length;
+
+		size_t quoted=0;
+
+		if(connection.standard_conforming_strings){
+			for(from=str; from<from_end; from++){
+				if(*from=='\'')
+					quoted++;
+			}
+		} else {
+			for(from=str; from<from_end; from++){
+				switch (*from) {
+				case '\'':
+				case '\\':
+					quoted++;
+				}
+			}
+		}
+
+		if(!quoted)
+			return str;
+
+		char *result=(char*)connection.services->malloc_atomic(length + quoted + 1);
+		char *to = result;
+
+		if(connection.standard_conforming_strings){
+			for(from=str; from<from_end; from++){
+				if(*from=='\'')
+					*to++= '\''; // "'" -> "''"
+				*to++=*from;
+			}
+		} else {
+			for(from=str; from<from_end; from++){
+				switch (*from) {
+				case '\'': // "'" -> "''"
+					*to++= '\'';
+					break;
+				case '\\': // "\" -> "\\"
+					*to++='\\';
+					break;
+				}
+				*to++=*from;
+			}
+		}
+		
+		*to=0;
 		return result;
 	}
-	
-	void query(void *aconnection, 
-				const char *astatement, 
-				size_t placeholders_count, Placeholder* placeholders, 
-				unsigned long offset, unsigned long limit,
-				SQL_Driver_query_event_handlers& handlers
-	){
+
+	void query(void *aconnection, const char *astatement, size_t placeholders_count, Placeholder* placeholders, unsigned long offset, unsigned long limit, SQL_Driver_query_event_handlers& handlers ){
 		Connection& connection=*static_cast<Connection*>(aconnection);
-		const char* client_charset=connection.client_charset;
 		SQL_Driver_services& services=*connection.services;
 		PGconn *conn=connection.conn;
 
-		bool transcode_needed=_transcode_required(connection);
+		const char* client_charset=connection.client_charset;
+		const char* request_charset=services.request_charset();
+		bool transcode_needed=client_charset && strcmp(client_charset, request_charset)!=0;
 
 		const char** paramValues;
 		if(placeholders_count>0){
@@ -243,16 +300,14 @@ public:
 			_bind_parameters(placeholders_count, placeholders, paramValues, connection, transcode_needed);
 		}
 
-		// transcode query from $request:charset to ?ClientCharset
+		size_t statement_size=0;
 		if(transcode_needed){
-			size_t length=strlen(astatement);
-			services.transcode(astatement, length,
-				astatement, length,
-				services.request_charset(),
-				connection.client_charset);
+			// transcode query from $request:charset to ?ClientCharset
+			statement_size=strlen(astatement);
+			services.transcode(astatement, statement_size, astatement, statement_size, request_charset, client_charset);
 		}
 
-		const char *statement=_preprocess_statement(connection, astatement, offset, limit);
+		const char *statement=_preprocess_statement(connection, astatement, statement_size, offset, limit);
 		// error after prepare?
 
 		PGresult *res;
@@ -264,45 +319,48 @@ public:
 		if(!res) 
 			throwPQerror;
 
+		bool failed=false;
+		SQL_Error sql_error;
+
 		switch(PQresultStatus(res)) {
-			case PGRES_EMPTY_QUERY: 
+			case PGRES_EMPTY_QUERY:
 				PQclear_throw("no query");
 				break;
 			case PGRES_COMMAND_OK: // empty result: insert|delete|update|...
 				PQclear(res);
 				return;
 			case PGRES_TUPLES_OK: 
-				break;	
+				break;
 			default:
 				PQclear_throwPQerror;
 				break;
 		}
 		
-		int column_count=PQnfields(res);
-		if(!column_count)
-			PQclear_throw("result contains no columns");
-
-		bool failed=false;
-		SQL_Error sql_error;
 #define CHECK(afailed) \
 		if(afailed) { \
 			failed=true; \
 			goto cleanup; \
 		}
 
-		for(int i=0; i<column_count; i++){
+		size_t column_count=PQnfields(res);
+		if(!column_count)
+			PQclear_throw("result contains no columns");
+
+		if(column_count>MAX_COLS)
+			column_count=MAX_COLS;
+
+		unsigned int column_types[MAX_COLS];
+
+		for(size_t i=0; i<column_count; i++){
+			column_types[i]=PQftype(res, i);
+
 			char *name=PQfname(res, i);
 			size_t length=strlen(name);
-			char* strm=(char*)services.malloc(length+1);
-			memcpy(strm, name, length+1);
-			const char* str=strm;
-
-			// transcode column name from ?ClientCharset to $request:charset
-			if(transcode_needed) 
-				services.transcode(str, length,
-					str, length,
-					connection.client_charset,
-					services.request_charset());
+			const char* str=strdup(services, name, length);
+
+			if(transcode_needed)
+				// transcode column name from ?ClientCharset to $request:charset
+				services.transcode(str, length, str, length, client_charset, request_charset);
 
 			CHECK(handlers.add_column(sql_error, str, length));
 		}
@@ -312,60 +370,80 @@ public:
 		if(unsigned long row_count=(unsigned long)PQntuples(res))
 			for(unsigned long r=0; r<row_count; r++) {
 				CHECK(handlers.add_row(sql_error));
-				for(int i=0; i<column_count; i++){
-					const char *cell=PQgetvalue(res, r, i);
-					size_t length;
-					const char* str;
-					if(PQftype(res, i)==OIDOID) {
-						// ObjectID column, read object bytes
+				for(size_t i=0; i<column_count; i++){
+					char *cell=PQgetvalue(res, r, i);
 
-						char *error_pos=0;
-						Oid oid=cell?atoi(cell):0;
-						int fd=lo_open(conn, oid, INV_READ);
-						if(fd>=0) {
-							// seek to end
-							if(lo_lseek(conn, fd, 0, SEEK_END)<0)
-								PQclear_throwPQerror;
-							// get length
-							int size_tell=lo_tell(conn, fd);
-							if(size_tell<0)
-								PQclear_throwPQerror;
-							// seek to begin
-							if(lo_lseek(conn, fd, 0, SEEK_SET)<0)
-								PQclear_throwPQerror;
-							length=(size_t)size_tell;
-							if(length) {
-								// read 
-								char* strm=(char*)services.malloc(length+1);
-								if(!lo_read_ex(conn, fd, strm, size_tell))
-									PQclear_throw("lo_read can not read all bytes of object");
-								strm[length]=0;
-								str=strm;
-							} else
-								str=0;
-							if(lo_close(conn, fd)<0)
-								PQclear_throwPQerror;
-						} else
-							PQclear_throwPQerror;
-					} else {
-						// normal column, read it normally
-						length=(size_t)PQgetlength(res, r, i);
-						if(length) {
-							char* strm=(char*)services.malloc(length+1);
-							memcpy(strm, cell, length+1);
-							str=strm;
-						} else
-							str=0;
-					}
+					size_t length=0;
+					const char* str;
 
-					if(transcode_needed && str && length){
-						// transcode cell value from ?ClientCharset to $request:charset
-						services.transcode(str, length,
-							str, length,
-							connection.client_charset,
-							services.request_charset());
+					switch(column_types[i]){
+						case BOOLOID:
+						case INT8OID:
+						case INT2OID:
+						case INT4OID:
+						case FLOAT4OID:
+						case FLOAT8OID:
+						case DATEOID:
+						case TIMEOID:
+						case TIMESTAMPOID:
+						case TIMESTAMPTZOID:
+						case TIMETZOID:
+						case NUMERICOID:
+							length=(size_t)PQgetlength(res, r, i);
+							str=length ? strdup(services, cell, length) : 0;
+							// transcode is never required for these types
+							break;
+						case OIDOID:
+							{
+								Oid oid=cell?atoi(cell):0;
+								int fd=lo_open(conn, oid, INV_READ);
+								if(fd>=0){
+									// seek to end
+									if(lo_lseek(conn, fd, 0, SEEK_END)<0)
+										PQclear_throwPQerror;
+									// get length
+									int size_tell=lo_tell(conn, fd);
+									if(size_tell<0)
+										PQclear_throwPQerror;
+									// seek to begin
+									if(lo_lseek(conn, fd, 0, SEEK_SET)<0)
+										PQclear_throwPQerror;
+									length=(size_t)size_tell;
+									if(length){
+										// read 
+										char* strm=(char*)services.malloc(length+1);
+										if(!lo_read_ex(conn, fd, strm, size_tell))
+											PQclear_throw("lo_read can not read all bytes of object");
+										strm[length]=0;
+										str=strm;
+										if(transcode_needed) {
+											// transcode cell value from ?ClientCharset to $request:charset
+											services.transcode(str, length,
+												str, length,
+												client_charset,
+												request_charset);
+										}
+									} else
+										str=0;
+									if(lo_close(conn, fd)<0)
+										PQclear_throwPQerror;
+								} else
+									PQclear_throwPQerror;
+								break;
+							}
+						default:
+							// normal column, read it normally
+							length=(size_t)PQgetlength(res, r, i);
+							str=length ? strdup(services, cell, length) : 0;
+							if(transcode_needed) {
+								// transcode cell value from ?ClientCharset to $request:charset
+								services.transcode(str, length,
+									str, length,
+									client_charset,
+									request_charset);
+							}
+							break;
 					}
-
 					CHECK(handlers.add_row_cell(sql_error, str, length));
 				}
 			}
@@ -376,66 +454,42 @@ cleanup:
 	}
 
 private:
-	void _bind_parameters(
-				size_t placeholders_count, 
-				Placeholder* placeholders, 
-				const char** paramValues,
-				Connection& connection,
-				bool transcode_needed
-	){
+	void _bind_parameters( size_t placeholders_count, Placeholder* placeholders, const char** paramValues, Connection& connection, bool transcode_needed){
 		for(size_t i=0; i<placeholders_count; i++){
 			Placeholder& ph=placeholders[i];
 			if(transcode_needed){
 				size_t name_length;
-				size_t value_length;
-				connection.services->transcode(ph.name, strlen(ph.name),
-					ph.name, name_length,
-					connection.services->request_charset(),
-					connection.client_charset);
+				connection.services->transcode(ph.name, strlen(ph.name), ph.name, name_length, connection.services->request_charset(), connection.client_charset);
 
 				if(ph.value) {
-					connection.services->transcode(ph.value, strlen(ph.value),
-						ph.value, value_length,
-						connection.services->request_charset(),
-						connection.client_charset);
+					size_t value_length;
+					connection.services->transcode(ph.value, strlen(ph.value), ph.value, value_length, connection.services->request_charset(), connection.client_charset);
 				}
 			}
-			int name_numner=atoi(ph.name);
-			if(name_numner <= 0 || name_numner > placeholders_count)
+			int name_number=atoi(ph.name);
+			if(name_number <= 0 || (size_t)name_number > placeholders_count)
 				connection.services->_throw("bad bind parameter key");
 
-			paramValues[name_numner-1]=ph.value;
+			paramValues[name_number-1]=ph.value;
 		}
 	}
 	
-	
-	/**
-		Executes a query and throw away the result.
-	*/
+	// executes a query and throw away the result.
 	void _execute_cmd(const Connection& connection, const char *query){
 		if(PGresult *res=PQexec(connection.conn, query))
-			PQclear(res); // throw out the result [don't need but must call]
+			PQclear(res); // throw away the result [don't need but must call]
 		else
 			throwPQerror;
 	}
 
-	void _begin_transaction(Connection& connection){
-		if(connection.autocommit)
-			_execute_cmd(connection, "BEGIN");
-	}
-
-	const char *_preprocess_statement(
-					Connection& connection,
-					const char *astatement,
-					unsigned long offset,
-					unsigned long limit
-	){
+	const char *_preprocess_statement(Connection& connection, const char *astatement, size_t statement_size, unsigned long offset, unsigned long limit){
 		PGconn *conn=connection.conn;
 
-		size_t statement_size=strlen(astatement);
+		if(!statement_size)
+			statement_size=strlen(astatement);
 
 		char *result=(char *)connection.services->malloc(statement_size
-			+MAX_NUMBER*2+15 // limit # offset #
+			+MAX_NUMBER*2+15 // " limit # offset #"
 			+MAX_STRING // in case of short 'strings'
 			+1);
 		// offset & limit -> suffixes
@@ -444,9 +498,9 @@ private:
 			char *cur=result;
 			memcpy(cur, astatement, statement_size); cur+=statement_size;
 			if(limit!=SQL_NO_LIMIT)
-				cur+=snprintf(cur, 7+MAX_NUMBER, " limit %u", limit);
+				cur+=snprintf(cur, 7+MAX_NUMBER, " limit %lu", limit);
 			if(offset)
-				cur+=snprintf(cur, 8+MAX_NUMBER, " offset %u", offset);
+				cur+=snprintf(cur, 8+MAX_NUMBER, " offset %lu", offset);
 			o=result;
 		} else 
 			o=astatement;
@@ -456,16 +510,12 @@ private:
 		while(*o) {
 			if(
 				o[0]=='/' &&
-				o[1]=='*' && 
+				o[1]=='*' &&
 				o[2]=='*') { // name start
 				const char* saved_o=o;
 				o+=3;
 				while(*o)
-					if(
-						o[0]=='*' &&
-						o[1]=='*' &&
-						o[2]=='/' &&
-						o[3]=='\'') { // name end
+					if(o[0]=='*' && 	o[1]=='*' && o[2]=='/' && o[3]=='\'') { // name end
 						saved_o=0; // found, marking that
 						o+=4;
 						Oid oid=lo_creat(conn, INV_READ|INV_WRITE);
@@ -510,10 +560,6 @@ private:
 		return result;
 	}
 
-	bool _transcode_required(Connection& connection){
-		return (connection.client_charset && strcmp(connection.client_charset, connection.services->request_charset())!=0);
-	}
-
 private: // lo_read/write exchancements
 
 	bool lo_read_ex(PGconn *conn, int fd, const/*paf*/ char *buf, size_t len) {
@@ -591,11 +637,19 @@ private: // conn client library funcs
 private: // conn client library funcs linking
 
 	const char *dlink(const char *dlopen_file_spec) {
-		if(lt_dlinit())
-			return lt_dlerror();
+		if(lt_dlinit()){
+			if(const char* result=lt_dlerror())
+				return result;
+			return "can not prepare to dynamic loading";
+		}
+
 		lt_dlhandle handle=lt_dlopen(dlopen_file_spec);
-		if(!handle)
+
+		if(!handle){
+			if(const char* result=lt_dlerror())
+				return result;
 			return "can not open the dynamic link module";
+		}
 
 		#define DSLINK(name, action) \
 			name=(t_##name)lt_dlsym(handle, #name); \
@@ -619,11 +673,11 @@ private: // conn client library funcs li
 		DLINK(PQexecParams);
 		DLINK(PQftype);
 		DLINK(PQescapeStringConn);
-		DLINK(lo_open);		DLINK(lo_close);
-		DLINK(lo_read);		DLINK(lo_write);
-		DLINK(lo_lseek);		DLINK(lo_creat);
-		DLINK(lo_tell);		DLINK(lo_unlink);
-		DLINK(lo_import);		DLINK(lo_export);
+		DLINK(lo_open);   DLINK(lo_close);
+		DLINK(lo_read);   DLINK(lo_write);
+		DLINK(lo_lseek);  DLINK(lo_creat);
+		DLINK(lo_tell);   DLINK(lo_unlink);
+		DLINK(lo_import); DLINK(lo_export);
 
 		return 0;
 	}