diff options
Diffstat (limited to 'src/backend/tcop/postgres.c')
| -rw-r--r-- | src/backend/tcop/postgres.c | 166 |
1 files changed, 97 insertions, 69 deletions
diff --git a/src/backend/tcop/postgres.c b/src/backend/tcop/postgres.c index 1048d2fa1c6..fcc6591f7c0 100644 --- a/src/backend/tcop/postgres.c +++ b/src/backend/tcop/postgres.c @@ -8,7 +8,7 @@ * * * IDENTIFICATION - * $Header: /cvsroot/pgsql/src/backend/tcop/postgres.c,v 1.321 2003/04/17 22:26:01 tgl Exp $ + * $Header: /cvsroot/pgsql/src/backend/tcop/postgres.c,v 1.322 2003/04/19 00:02:29 tgl Exp $ * * NOTES * this is the "main" module of the postgres backend and @@ -133,7 +133,9 @@ static const char *CreateCommandTag(Node *parsetree); /* ---------------- * InteractiveBackend() is called for user interactive connections - * the string entered by the user is placed in its parameter inBuf. + * + * the string entered by the user is placed in its parameter inBuf, + * and we act like a Q message was received. * * EOF is returned if end-of-file input is seen; time to shut down. * ---------------- @@ -155,6 +157,7 @@ InteractiveBackend(StringInfo inBuf) /* Reset inBuf to empty */ inBuf->len = 0; inBuf->data[0] = '\0'; + inBuf->cursor = 0; for (;;) { @@ -214,6 +217,9 @@ InteractiveBackend(StringInfo inBuf) break; } + /* Add '\0' to make it look the same as message case. */ + appendStringInfoChar(inBuf, (char) '\0'); + /* * if the query echo flag was given, print the query.. */ @@ -227,66 +233,79 @@ InteractiveBackend(StringInfo inBuf) /* ---------------- * SocketBackend() Is called for frontend-backend connections * - * If the input is a query (case 'Q') then the string entered by - * the user is placed in its parameter inBuf. - * - * If the input is a fastpath function call (case 'F') then - * the function call is processed in HandleFunctionRequest() - * (now called from PostgresMain()). + * Returns the message type code, and loads message body data into inBuf. * * EOF is returned if the connection is lost. * ---------------- */ - static int SocketBackend(StringInfo inBuf) { int qtype; /* - * get input from the frontend + * Get message type code from the frontend. */ qtype = pq_getbyte(); + if (qtype == EOF) /* frontend disconnected */ + { + elog(COMMERROR, "unexpected EOF on client connection"); + return qtype; + } + + /* + * Validate message type code before trying to read body; if we have + * lost sync, better to say "command unknown" than to run out of memory + * because we used garbage as a length word. + */ switch (qtype) { - case EOF: - /* frontend disconnected */ + case 'Q': /* simple query */ + if (PG_PROTOCOL_MAJOR(FrontendProtocol) < 3) + { + /* old style without length word; convert */ + if (pq_getstring(inBuf)) + { + elog(COMMERROR, "unexpected EOF on client connection"); + return EOF; + } + } break; - /* - * 'Q': user entered a query - */ - case 'Q': - if (pq_getstr(inBuf)) - return EOF; + case 'F': /* fastpath function call */ break; - /* - * 'F': calling user/system functions - */ - case 'F': - if (pq_getstr(inBuf)) - return EOF; /* ignore "string" at start of F message */ + case 'X': /* terminate */ break; - /* - * 'X': frontend is exiting - */ - case 'X': + case 'd': /* copy data */ + case 'c': /* copy done */ + case 'f': /* copy fail */ + /* Accept but ignore these messages, per protocol spec */ break; + default: /* - * otherwise we got garbage from the frontend. - * - * XXX are we certain that we want to do an elog(FATAL) here? - * -cim 1/24/90 + * Otherwise we got garbage from the frontend. We treat this + * as fatal because we have probably lost message boundary sync, + * and there's no good way to recover. */ - default: elog(FATAL, "Socket command type %c unknown", qtype); break; } + /* + * In protocol version 3, all frontend messages have a length word + * next after the type code; we can read the message contents + * independently of the type. + */ + if (PG_PROTOCOL_MAJOR(FrontendProtocol) >= 3) + { + if (pq_getmessage(inBuf, 0)) + return EOF; /* suitable message already logged */ + } + return qtype; } @@ -1220,19 +1239,17 @@ int PostgresMain(int argc, char *argv[], const char *username) { int flag; - const char *DBName = NULL; + char *potential_DataDir = NULL; bool secure; int errs = 0; int debug_flag = 0; GucContext ctx; GucSource gucsource; char *tmp; - int firstchar; StringInfo parser_input; - - char *potential_DataDir = NULL; + bool send_rfq; /* * Catch standard options before doing much else. This even works on @@ -1815,7 +1832,7 @@ PostgresMain(int argc, char *argv[], const char *username) if (!IsUnderPostmaster) { puts("\nPOSTGRES backend interactive interface "); - puts("$Revision: 1.321 $ $Date: 2003/04/17 22:26:01 $\n"); + puts("$Revision: 1.322 $ $Date: 2003/04/19 00:02:29 $\n"); } /* @@ -1902,6 +1919,8 @@ PostgresMain(int argc, char *argv[], const char *username) PG_SETMASK(&UnBlockSig); + send_rfq = true; /* initially, or after error */ + /* * Non-error queries loop here. */ @@ -1922,7 +1941,11 @@ PostgresMain(int argc, char *argv[], const char *username) * * Note: this includes fflush()'ing the last of the prior output. */ - ReadyForQuery(whereToSendOutput); + if (send_rfq) + { + ReadyForQuery(whereToSendOutput); + send_rfq = false; + } /* ---------- * Tell the statistics collector what we've collected @@ -1986,20 +2009,36 @@ PostgresMain(int argc, char *argv[], const char *username) */ switch (firstchar) { + case 'Q': /* simple query */ /* - * 'F' indicates a fastpath call. - */ - case 'F': - /* ---------- - * Tell the collector what we're doing - * ---------- + * Process the query string. + * + * Note: transaction command start/end is now done within + * pg_exec_query_string(), not here. */ + if (log_statement_stats) + ResetUsage(); + + pgstat_report_activity(parser_input->data); + + pg_exec_query_string(parser_input, + whereToSendOutput, + QueryContext); + + if (log_statement_stats) + ShowUsage("QUERY STATISTICS"); + + send_rfq = true; + break; + + case 'F': /* fastpath function call */ + /* Tell the collector what we're doing */ pgstat_report_activity("<FASTPATH> function call"); /* start an xact for this function invocation */ start_xact_command(); - if (HandleFunctionRequest() == EOF) + if (HandleFunctionRequest(parser_input) == EOF) { /* lost frontend connection during F message input */ @@ -2015,29 +2054,8 @@ PostgresMain(int argc, char *argv[], const char *username) /* commit the function-invocation transaction */ finish_xact_command(false); - break; - - /* - * 'Q' indicates a user query - */ - case 'Q': - /* - * otherwise, process the input string. - * - * Note: transaction command start/end is now done within - * pg_exec_query_string(), not here. - */ - if (log_statement_stats) - ResetUsage(); - pgstat_report_activity(parser_input->data); - - pg_exec_query_string(parser_input, - whereToSendOutput, - QueryContext); - - if (log_statement_stats) - ShowUsage("QUERY STATISTICS"); + send_rfq = true; break; /* @@ -2064,8 +2082,18 @@ PostgresMain(int argc, char *argv[], const char *username) */ proc_exit(0); + case 'd': /* copy data */ + case 'c': /* copy done */ + case 'f': /* copy fail */ + /* + * Accept but ignore these messages, per protocol spec; + * we probably got here because a COPY failed, and the + * frontend is still sending data. + */ + break; + default: - elog(ERROR, "unknown frontend message was received"); + elog(FATAL, "Socket command type %c unknown", firstchar); } #ifdef MEMORY_CONTEXT_CHECKING |