Simplify PID extraction

Using bind message to obtain parameter information, rather than determining whether the query is parameterized from the query itself. Multiple parameters are not possible in this case, as PostgreSQL itself rejects multi-parameter  pg_cancel_backend() and pg_terminate_backend() and only accepts a single parameter for these functions.

Author: rahim-kanji

lib/PgSQL_Session.cpp

@@ -5191,91 +5191,59 @@ bool PgSQL_Session::handle_command_query_kill(PtrSize_t* pkt) {
 			// Note: This simple check might have false positives if $1 appears in comments or string literals
 			// but those cases would fail later when checking bind_msg or parameter validation
 			const char* digest_text = CurrentQuery.QueryParserArgs.digest_text;
-			bool is_parameterized = strstr(digest_text, "$1") != nullptr;
+
+			// Use protocol facts (Bind) 
+			const PgSQL_Bind_Message* bind_msg = CurrentQuery.extended_query_info.bind_msg;
+			const bool is_parameterized = bind_msg && bind_msg->data().num_param_values > 0;
 			if (is_parameterized) {
-				// Check if there are multiple parameters (e.g., $1, $2)
-				// Look for $2, $3, etc. to reject multiple parameters
-				const char* p = digest_text;
-				int max_param = 0;
-				while ((p = strstr(p, "$")) != nullptr) {
-					p++; // Skip '$'
-					if (isdigit(*p)) {
-						char* end;
-						long param_num = strtol(p, &end, 10);
-						if (p != end) { // check if any digits were parsed
-							if (param_num > max_param) {
-								max_param = static_cast<int>(param_num);
-							}
-							p = end;
-							continue;
-						}
-					}
-					p++;
-				}
-				if (max_param > 1) {
-					// Multiple parameters not supported
+				// Check that we have exactly one parameter
+				if (bind_msg->data().num_param_values != 1) {
 					send_parameter_error_response("function requires exactly one parameter");
 					l_free(pkt->size, pkt->ptr);
 					return true;
 				}
-						
-				// Handle parameterized query
-				if (CurrentQuery.extended_query_info.bind_msg) {
-					const PgSQL_Bind_Message* bind_msg = CurrentQuery.extended_query_info.bind_msg;
-					auto param_reader = bind_msg->get_param_value_reader();
-					PgSQL_Param_Value param;
-							
-					// Check that we have exactly one parameter
-					if (bind_msg->data().num_param_values != 1) {
-						send_parameter_error_response("function requires exactly one parameter");
-						l_free(pkt->size, pkt->ptr);
-						return true;
+				auto param_reader = bind_msg->get_param_value_reader();
+				PgSQL_Param_Value param;
+				if (param_reader.next(&param)) {
+					// Get parameter format (default to text format 0)
+					uint16_t param_format = 0;
+					if (bind_msg->data().num_param_formats == 1) {
+						// Single format applies to all parameters
+						auto format_reader = bind_msg->get_param_format_reader();
+						format_reader.next(&param_format);
 					}
-							
-					if (param_reader.next(&param)) {
-						// Get parameter format (default to text format 0)
-						uint16_t param_format = 0;
-						if (bind_msg->data().num_param_formats == 1) {
-							// Single format applies to all parameters
-							auto format_reader = bind_msg->get_param_format_reader();
-							format_reader.next(&param_format);
-						}
 
-						// Extract PID from parameter
-						int32_t pid = extract_pid_from_param(param, param_format);
-						if (pid > 0) {
-							// Determine if this is terminate or cancel
-							int tki = -1;
-							if (CurrentQuery.PgQueryCmd == PGSQL_QUERY_TERMINATE_BACKEND) {
-								tki = 0;  // Connection terminate
-							} else if (CurrentQuery.PgQueryCmd == PGSQL_QUERY_CANCEL_BACKEND) {
-								tki = 1;  // Query cancel
-							}
+					// Extract PID from parameter
+					int32_t pid = extract_pid_from_param(param, param_format);
+					if (pid > 0) {
+						// Determine if this is terminate or cancel
+						int tki = -1;
+						if (CurrentQuery.PgQueryCmd == PGSQL_QUERY_TERMINATE_BACKEND) {
+							tki = 0;  // Connection terminate
+						} else if (CurrentQuery.PgQueryCmd == PGSQL_QUERY_CANCEL_BACKEND) {
+							tki = 1;  // Query cancel
+						}
 
-							if (tki >= 0) {
-								return handle_kill_success(pid, tki, digest_text, mc, pkt);
-							}
-						} else {
-							// Invalid parameter - send appropriate error response
-							if (pid == -2) {
-								// NULL parameter
-								send_parameter_error_response("NULL is not allowed", PGSQL_ERROR_CODES::ERRCODE_NULL_VALUE_NOT_ALLOWED);
-							} else if (pid == -1) {
-								// Invalid format (not a valid integer)
-								send_parameter_error_response("invalid input syntax for integer", PGSQL_ERROR_CODES::ERRCODE_INVALID_PARAMETER_VALUE);
-							} else if (pid == 0) {
-								// PID <= 0 (non-positive)
-								send_parameter_error_response("PID must be a positive integer", PGSQL_ERROR_CODES::ERRCODE_INVALID_PARAMETER_VALUE);
-							}
-							l_free(pkt->size, pkt->ptr);
-							return true;
+						if (tki >= 0) {
+							return handle_kill_success(pid, tki, digest_text, mc, pkt);
 						}
 					} else {
-						// No parameter available - this shouldn't happen
-						return false;
+						// Invalid parameter - send appropriate error response
+						if (pid == -2) {
+							// NULL parameter
+							send_parameter_error_response("NULL is not allowed", PGSQL_ERROR_CODES::ERRCODE_NULL_VALUE_NOT_ALLOWED);
+						} else if (pid == -1) {
+							// Invalid format (not a valid integer)
+							send_parameter_error_response("invalid input syntax for integer", PGSQL_ERROR_CODES::ERRCODE_INVALID_PARAMETER_VALUE);
+						} else if (pid == 0) {
+							// PID <= 0 (non-positive)
+							send_parameter_error_response("PID must be a positive integer", PGSQL_ERROR_CODES::ERRCODE_INVALID_PARAMETER_VALUE);
+						}
+						l_free(pkt->size, pkt->ptr);
+						return true;
 					}
 				} else {
-					// No bind message available (shouldn't happen for Execute phase)
+					// No parameter available - this shouldn't happen
 					return false;
 				}
 			} else {