/*
* SendQuery: send the query string to the backend
* (and print out results)
*
* Note: This is the "front door" way to send a query. That is, use it to
* send queries actually entered by the user. These queries will be subject to
* single step mode.
* To send "back door" queries (generated by slash commands, etc.) in a
* controlled way, use PSQLexec().
*
* Returns true if the query executed successfully, false otherwise.
*/
bool
SendQuery(const char *query)
{
PGresult *results;
TimevalStruct before,
after;
bool OK;
if (!pset.db)
{
psql_error("You are currently not connected to a database.\n");
return false;
}
if (GetVariableBool(pset.vars, "SINGLESTEP"))
{
char buf[3];
printf(gettext("***(Single step mode: verify command)*******************************************\n"
"%s\n"
"***(press return to proceed or enter x and return to cancel)********************\n"),
query);
fflush(stdout);
if (fgets(buf, sizeof(buf), stdin) != NULL)
if (buf[0] == 'x')
return false;
}
else if (VariableEquals(pset.vars, "ECHO", "queries"))
{
puts(query);
fflush(stdout);
}
SetCancelConn();
if (PQtransactionStatus(pset.db) == PQTRANS_IDLE &&
!GetVariableBool(pset.vars, "AUTOCOMMIT") &&
!is_transact_command(query))
{
results = PQexec(pset.db, "BEGIN");
if (PQresultStatus(results) != PGRES_COMMAND_OK)
{
psql_error("%s", PQerrorMessage(pset.db));
PQclear(results);
ResetCancelConn();
return false;
}
PQclear(results);
}
if (pset.timing)
GETTIMEOFDAY(&before);
results = PQexec(pset.db, query);
/* these operations are included in the timing result: */
OK = (AcceptResult(results) && ProcessCopyResult(results));
if (pset.timing)
GETTIMEOFDAY(&after);
/* but printing results isn't: */
if (OK)
OK = PrintQueryResults(results);
PQclear(results);
/* Possible microtiming output */
if (OK && pset.timing)
printf(gettext("Time: %.3f ms\n"), DIFF_MSEC(&after, &before));
/* check for events that may occur during query execution */
if (pset.encoding != PQclientEncoding(pset.db) &&
PQclientEncoding(pset.db) >= 0)
{
/* track effects of SET CLIENT_ENCODING */
pset.encoding = PQclientEncoding(pset.db);
pset.popt.topt.encoding = pset.encoding;
SetVariable(pset.vars, "ENCODING",
pg_encoding_to_char(pset.encoding));
}
PrintNotifications();
return OK;
}
/*
* Main processing loop for reading lines of input
* and sending them to the backend.
*
* This loop is re-entrant. May be called by \i command
* which reads input from a file.
*/
int
MainLoop(FILE *source)
{
PsqlScanState scan_state; /* lexer working state */
PQExpBuffer query_buf; /* buffer for query being accumulated */
PQExpBuffer previous_buf; /* if there isn't anything in the new
* buffer yet, use this one for \e, etc. */
char *line; /* current line of input */
int added_nl_pos;
bool success;
volatile int successResult = EXIT_SUCCESS;
volatile backslashResult slashCmdStatus = CMD_UNKNOWN;
volatile promptStatus_t prompt_status = PROMPT_READY;
volatile int count_eof = 0;
volatile bool die_on_error = false;
/* Save the prior command source */
FILE *prev_cmd_source;
bool prev_cmd_interactive;
unsigned int prev_lineno;
/* Save old settings */
prev_cmd_source = pset.cur_cmd_source;
prev_cmd_interactive = pset.cur_cmd_interactive;
prev_lineno = pset.lineno;
/* Establish new source */
pset.cur_cmd_source = source;
pset.cur_cmd_interactive = ((source == stdin) && !pset.notty);
pset.lineno = 0;
/* Create working state */
scan_state = psql_scan_create();
query_buf = createPQExpBuffer();
previous_buf = createPQExpBuffer();
if (!query_buf || !previous_buf)
{
psql_error("out of memory\n");
exit(EXIT_FAILURE);
}
/* main loop to get queries and execute them */
while (successResult == EXIT_SUCCESS)
{
/*
* Welcome code for Control-C
*/
if (cancel_pressed)
{
if (!pset.cur_cmd_interactive)
{
/*
* You get here if you stopped a script with Ctrl-C and a
* query cancel was issued. In that case we don't do the
* longjmp, so the query routine can finish nicely.
*/
successResult = EXIT_USER;
break;
}
cancel_pressed = false;
}
#ifndef WIN32
if (sigsetjmp(main_loop_jmp, 1) != 0)
{
/* got here with longjmp */
/* reset parsing state */
resetPQExpBuffer(query_buf);
psql_scan_finish(scan_state);
psql_scan_reset(scan_state);
count_eof = 0;
slashCmdStatus = CMD_UNKNOWN;
prompt_status = PROMPT_READY;
if (pset.cur_cmd_interactive)
putc('\n', stdout);
else
{
successResult = EXIT_USER;
break;
}
}
/*
* establish the control-C handler only after main_loop_jmp is
* ready
*/
pqsignal(SIGINT, handle_sigint); /* control-C => cancel */
#else /* WIN32 */
setup_cancel_handler();
#endif
fflush(stdout);
if (slashCmdStatus == CMD_NEWEDIT)
{
/*
* just returned from editing the line? then just copy to the
* input buffer
*/
line = pg_strdup(query_buf->data);
/* reset parsing state since we are rescanning whole line */
resetPQExpBuffer(query_buf);
psql_scan_reset(scan_state);
slashCmdStatus = CMD_UNKNOWN;
prompt_status = PROMPT_READY;
}
/*
* otherwise, get another line
*/
else if (pset.cur_cmd_interactive)
{
/* May need to reset prompt, eg after \r command */
if (query_buf->len == 0)
prompt_status = PROMPT_READY;
line = gets_interactive(get_prompt(prompt_status));
}
else
line = gets_fromFile(source);
/*
* query_buf holds query already accumulated. line is the
* malloc'd new line of input (note it must be freed before
* looping around!)
*/
/* No more input. Time to quit, or \i done */
if (line == NULL)
{
if (pset.cur_cmd_interactive)
{
/* This tries to mimic bash's IGNOREEOF feature. */
count_eof++;
if (count_eof < GetVariableNum(pset.vars, "IGNOREEOF", 0, 10, false))
{
if (!QUIET())
printf(gettext("Use \"\\q\" to leave %s.\n"), pset.progname);
continue;
}
puts(QUIET() ? "" : "\\q");
}
break;
}
count_eof = 0;
pset.lineno++;
/* nothing left on line? then ignore */
if (line[0] == '\0' && !psql_scan_in_quote(scan_state))
{
free(line);
continue;
}
/* echo back if flag is set */
if (!pset.cur_cmd_interactive &&
VariableEquals(pset.vars, "ECHO", "all"))
puts(line);
fflush(stdout);
/* insert newlines into query buffer between source lines */
if (query_buf->len > 0)
{
appendPQExpBufferChar(query_buf, '\n');
added_nl_pos = query_buf->len;
}
else
added_nl_pos = -1; /* flag we didn't add one */
/* Setting this will not have effect until next line. */
die_on_error = GetVariableBool(pset.vars, "ON_ERROR_STOP");
/*
* Parse line, looking for command separators.
*/
psql_scan_setup(scan_state, line, strlen(line));
success = true;
while (success || !die_on_error)
{
PsqlScanResult scan_result;
promptStatus_t prompt_tmp = prompt_status;
scan_result = psql_scan(scan_state, query_buf, &prompt_tmp);
prompt_status = prompt_tmp;
/*
* Send command if semicolon found, or if end of line and
* we're in single-line mode.
*/
if (scan_result == PSCAN_SEMICOLON ||
(scan_result == PSCAN_EOL &&
GetVariableBool(pset.vars, "SINGLELINE")))
{
/* execute query */
success = SendQuery(query_buf->data);
slashCmdStatus = success ? CMD_SEND : CMD_ERROR;
resetPQExpBuffer(previous_buf);
appendPQExpBufferStr(previous_buf, query_buf->data);
resetPQExpBuffer(query_buf);
added_nl_pos = -1;
/* we need not do psql_scan_reset() here */
}
else if (scan_result == PSCAN_BACKSLASH)
{
/* handle backslash command */
/*
* If we added a newline to query_buf, and nothing else
* has been inserted in query_buf by the lexer, then strip
* off the newline again. This avoids any change to
* query_buf when a line contains only a backslash
* command.
*/
if (query_buf->len == added_nl_pos)
query_buf->data[--query_buf->len] = '\0';
added_nl_pos = -1;
slashCmdStatus = HandleSlashCmds(scan_state,
query_buf->len > 0 ?
query_buf : previous_buf);
success = slashCmdStatus != CMD_ERROR;
if ((slashCmdStatus == CMD_SEND || slashCmdStatus == CMD_NEWEDIT) &&
query_buf->len == 0)
{
/* copy previous buffer to current for handling */
appendPQExpBufferStr(query_buf, previous_buf->data);
}
if (slashCmdStatus == CMD_SEND)
{
success = SendQuery(query_buf->data);
resetPQExpBuffer(previous_buf);
appendPQExpBufferStr(previous_buf, query_buf->data);
resetPQExpBuffer(query_buf);
/* flush any paren nesting info after forced send */
psql_scan_reset(scan_state);
}
if (slashCmdStatus == CMD_TERMINATE)
break;
}
/* fall out of loop if lexer reached EOL */
if (scan_result == PSCAN_INCOMPLETE ||
scan_result == PSCAN_EOL)
break;
}
psql_scan_finish(scan_state);
free(line);
if (slashCmdStatus == CMD_TERMINATE)
{
successResult = EXIT_SUCCESS;
break;
}
if (!pset.cur_cmd_interactive)
{
if (!success && die_on_error)
successResult = EXIT_USER;
/* Have we lost the db connection? */
else if (!pset.db)
successResult = EXIT_BADCONN;
}
} /* while !endoffile/session */
/*
* Process query at the end of file without a semicolon
*/
if (query_buf->len > 0 && !pset.cur_cmd_interactive &&
successResult == EXIT_SUCCESS)
{
success = SendQuery(query_buf->data);
if (!success && die_on_error)
successResult = EXIT_USER;
else if (pset.db == NULL)
successResult = EXIT_BADCONN;
}
/*
* Reset SIGINT handler because main_loop_jmp will be invalid as soon
* as we exit this routine. If there is an outer MainLoop instance,
* it will re-enable ^C catching as soon as it gets back to the top of
* its loop and resets main_loop_jmp to point to itself.
*/
#ifndef WIN32
pqsignal(SIGINT, SIG_DFL);
#endif
destroyPQExpBuffer(query_buf);
destroyPQExpBuffer(previous_buf);
psql_scan_destroy(scan_state);
pset.cur_cmd_source = prev_cmd_source;
pset.cur_cmd_interactive = prev_cmd_interactive;
pset.lineno = prev_lineno;
return successResult;
} /* MainLoop() */
