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-rw-r--r--src/bin/psql/common.c2388
1 files changed, 2388 insertions, 0 deletions
diff --git a/src/bin/psql/common.c b/src/bin/psql/common.c
new file mode 100644
index 0000000..f5909f9
--- /dev/null
+++ b/src/bin/psql/common.c
@@ -0,0 +1,2388 @@
+/*
+ * psql - the PostgreSQL interactive terminal
+ *
+ * Copyright (c) 2000-2022, PostgreSQL Global Development Group
+ *
+ * src/bin/psql/common.c
+ */
+#include "postgres_fe.h"
+
+#include <ctype.h>
+#include <limits.h>
+#include <math.h>
+#include <pwd.h>
+#include <signal.h>
+#ifndef WIN32
+#include <unistd.h> /* for write() */
+#else
+#include <io.h> /* for _write() */
+#include <win32.h>
+#endif
+
+#include "command.h"
+#include "common.h"
+#include "common/logging.h"
+#include "copy.h"
+#include "crosstabview.h"
+#include "fe_utils/cancel.h"
+#include "fe_utils/mbprint.h"
+#include "fe_utils/string_utils.h"
+#include "portability/instr_time.h"
+#include "settings.h"
+
+static bool DescribeQuery(const char *query, double *elapsed_msec);
+static bool ExecQueryUsingCursor(const char *query, double *elapsed_msec);
+static int ExecQueryAndProcessResults(const char *query,
+ double *elapsed_msec,
+ bool *svpt_gone_p,
+ bool is_watch,
+ const printQueryOpt *opt,
+ FILE *printQueryFout);
+static bool command_no_begin(const char *query);
+static bool is_select_command(const char *query);
+
+
+/*
+ * openQueryOutputFile --- attempt to open a query output file
+ *
+ * fname == NULL selects stdout, else an initial '|' selects a pipe,
+ * else plain file.
+ *
+ * Returns output file pointer into *fout, and is-a-pipe flag into *is_pipe.
+ * Caller is responsible for adjusting SIGPIPE state if it's a pipe.
+ *
+ * On error, reports suitable error message and returns false.
+ */
+bool
+openQueryOutputFile(const char *fname, FILE **fout, bool *is_pipe)
+{
+ if (!fname || fname[0] == '\0')
+ {
+ *fout = stdout;
+ *is_pipe = false;
+ }
+ else if (*fname == '|')
+ {
+ *fout = popen(fname + 1, "w");
+ *is_pipe = true;
+ }
+ else
+ {
+ *fout = fopen(fname, "w");
+ *is_pipe = false;
+ }
+
+ if (*fout == NULL)
+ {
+ pg_log_error("%s: %m", fname);
+ return false;
+ }
+
+ return true;
+}
+
+/*
+ * setQFout
+ * -- handler for -o command line option and \o command
+ *
+ * On success, updates pset with the new output file and returns true.
+ * On failure, returns false without changing pset state.
+ */
+bool
+setQFout(const char *fname)
+{
+ FILE *fout;
+ bool is_pipe;
+
+ /* First make sure we can open the new output file/pipe */
+ if (!openQueryOutputFile(fname, &fout, &is_pipe))
+ return false;
+
+ /* Close old file/pipe */
+ if (pset.queryFout && pset.queryFout != stdout && pset.queryFout != stderr)
+ {
+ if (pset.queryFoutPipe)
+ pclose(pset.queryFout);
+ else
+ fclose(pset.queryFout);
+ }
+
+ pset.queryFout = fout;
+ pset.queryFoutPipe = is_pipe;
+
+ /* Adjust SIGPIPE handling appropriately: ignore signal if is_pipe */
+ set_sigpipe_trap_state(is_pipe);
+ restore_sigpipe_trap();
+
+ return true;
+}
+
+
+/*
+ * Variable-fetching callback for flex lexer
+ *
+ * If the specified variable exists, return its value as a string (malloc'd
+ * and expected to be freed by the caller); else return NULL.
+ *
+ * If "quote" isn't PQUOTE_PLAIN, then return the value suitably quoted and
+ * escaped for the specified quoting requirement. (Failure in escaping
+ * should lead to printing an error and returning NULL.)
+ *
+ * "passthrough" is the pointer previously given to psql_scan_set_passthrough.
+ * In psql, passthrough points to a ConditionalStack, which we check to
+ * determine whether variable expansion is allowed.
+ */
+char *
+psql_get_variable(const char *varname, PsqlScanQuoteType quote,
+ void *passthrough)
+{
+ char *result = NULL;
+ const char *value;
+
+ /* In an inactive \if branch, suppress all variable substitutions */
+ if (passthrough && !conditional_active((ConditionalStack) passthrough))
+ return NULL;
+
+ value = GetVariable(pset.vars, varname);
+ if (!value)
+ return NULL;
+
+ switch (quote)
+ {
+ case PQUOTE_PLAIN:
+ result = pg_strdup(value);
+ break;
+ case PQUOTE_SQL_LITERAL:
+ case PQUOTE_SQL_IDENT:
+ {
+ /*
+ * For these cases, we use libpq's quoting functions, which
+ * assume the string is in the connection's client encoding.
+ */
+ char *escaped_value;
+
+ if (!pset.db)
+ {
+ pg_log_error("cannot escape without active connection");
+ return NULL;
+ }
+
+ if (quote == PQUOTE_SQL_LITERAL)
+ escaped_value =
+ PQescapeLiteral(pset.db, value, strlen(value));
+ else
+ escaped_value =
+ PQescapeIdentifier(pset.db, value, strlen(value));
+
+ if (escaped_value == NULL)
+ {
+ const char *error = PQerrorMessage(pset.db);
+
+ pg_log_info("%s", error);
+ return NULL;
+ }
+
+ /*
+ * Rather than complicate the lexer's API with a notion of
+ * which free() routine to use, just pay the price of an extra
+ * strdup().
+ */
+ result = pg_strdup(escaped_value);
+ PQfreemem(escaped_value);
+ break;
+ }
+ case PQUOTE_SHELL_ARG:
+ {
+ /*
+ * For this we use appendShellStringNoError, which is
+ * encoding-agnostic, which is fine since the shell probably
+ * is too. In any case, the only special character is "'",
+ * which is not known to appear in valid multibyte characters.
+ */
+ PQExpBufferData buf;
+
+ initPQExpBuffer(&buf);
+ if (!appendShellStringNoError(&buf, value))
+ {
+ pg_log_error("shell command argument contains a newline or carriage return: \"%s\"",
+ value);
+ free(buf.data);
+ return NULL;
+ }
+ result = buf.data;
+ break;
+ }
+
+ /* No default: we want a compiler warning for missing cases */
+ }
+
+ return result;
+}
+
+
+/*
+ * for backend Notice messages (INFO, WARNING, etc)
+ */
+void
+NoticeProcessor(void *arg, const char *message)
+{
+ (void) arg; /* not used */
+ pg_log_info("%s", message);
+}
+
+
+
+/*
+ * Code to support query cancellation
+ *
+ * Before we start a query, we enable the SIGINT signal catcher to send a
+ * cancel request to the backend.
+ *
+ * SIGINT is supposed to abort all long-running psql operations, not only
+ * database queries. In most places, this is accomplished by checking
+ * cancel_pressed during long-running loops. However, that won't work when
+ * blocked on user input (in readline() or fgets()). In those places, we
+ * set sigint_interrupt_enabled true while blocked, instructing the signal
+ * catcher to longjmp through sigint_interrupt_jmp. We assume readline and
+ * fgets are coded to handle possible interruption.
+ *
+ * On Windows, currently this does not work, so control-C is less useful
+ * there.
+ */
+volatile bool sigint_interrupt_enabled = false;
+
+sigjmp_buf sigint_interrupt_jmp;
+
+static void
+psql_cancel_callback(void)
+{
+#ifndef WIN32
+ /* if we are waiting for input, longjmp out of it */
+ if (sigint_interrupt_enabled)
+ {
+ sigint_interrupt_enabled = false;
+ siglongjmp(sigint_interrupt_jmp, 1);
+ }
+#endif
+
+ /* else, set cancel flag to stop any long-running loops */
+ cancel_pressed = true;
+}
+
+void
+psql_setup_cancel_handler(void)
+{
+ setup_cancel_handler(psql_cancel_callback);
+}
+
+
+/* ConnectionUp
+ *
+ * Returns whether our backend connection is still there.
+ */
+static bool
+ConnectionUp(void)
+{
+ return PQstatus(pset.db) != CONNECTION_BAD;
+}
+
+
+
+/* CheckConnection
+ *
+ * Verify that we still have a good connection to the backend, and if not,
+ * see if it can be restored.
+ *
+ * Returns true if either the connection was still there, or it could be
+ * restored successfully; false otherwise. If, however, there was no
+ * connection and the session is non-interactive, this will exit the program
+ * with a code of EXIT_BADCONN.
+ */
+static bool
+CheckConnection(void)
+{
+ bool OK;
+
+ OK = ConnectionUp();
+ if (!OK)
+ {
+ if (!pset.cur_cmd_interactive)
+ {
+ pg_log_error("connection to server was lost");
+ exit(EXIT_BADCONN);
+ }
+
+ fprintf(stderr, _("The connection to the server was lost. Attempting reset: "));
+ PQreset(pset.db);
+ OK = ConnectionUp();
+ if (!OK)
+ {
+ fprintf(stderr, _("Failed.\n"));
+
+ /*
+ * Transition to having no connection; but stash away the failed
+ * connection so that we can still refer to its parameters in a
+ * later \connect attempt. Keep the state cleanup here in sync
+ * with do_connect().
+ */
+ if (pset.dead_conn)
+ PQfinish(pset.dead_conn);
+ pset.dead_conn = pset.db;
+ pset.db = NULL;
+ ResetCancelConn();
+ UnsyncVariables();
+ }
+ else
+ {
+ fprintf(stderr, _("Succeeded.\n"));
+
+ /*
+ * Re-sync, just in case anything changed. Keep this in sync with
+ * do_connect().
+ */
+ SyncVariables();
+ connection_warnings(false); /* Must be after SyncVariables */
+ }
+ }
+
+ return OK;
+}
+
+
+
+
+/*
+ * AcceptResult
+ *
+ * Checks whether a result is valid, giving an error message if necessary;
+ * and ensures that the connection to the backend is still up.
+ *
+ * Returns true for valid result, false for error state.
+ */
+static bool
+AcceptResult(const PGresult *result, bool show_error)
+{
+ bool OK;
+
+ if (!result)
+ OK = false;
+ else
+ switch (PQresultStatus(result))
+ {
+ case PGRES_COMMAND_OK:
+ case PGRES_TUPLES_OK:
+ case PGRES_EMPTY_QUERY:
+ case PGRES_COPY_IN:
+ case PGRES_COPY_OUT:
+ /* Fine, do nothing */
+ OK = true;
+ break;
+
+ case PGRES_BAD_RESPONSE:
+ case PGRES_NONFATAL_ERROR:
+ case PGRES_FATAL_ERROR:
+ OK = false;
+ break;
+
+ default:
+ OK = false;
+ pg_log_error("unexpected PQresultStatus: %d",
+ PQresultStatus(result));
+ break;
+ }
+
+ if (!OK && show_error)
+ {
+ const char *error = PQerrorMessage(pset.db);
+
+ if (strlen(error))
+ pg_log_info("%s", error);
+
+ CheckConnection();
+ }
+
+ return OK;
+}
+
+
+/*
+ * Set special variables from a query result
+ * - ERROR: true/false, whether an error occurred on this query
+ * - SQLSTATE: code of error, or "00000" if no error, or "" if unknown
+ * - ROW_COUNT: how many rows were returned or affected, or "0"
+ * - LAST_ERROR_SQLSTATE: same for last error
+ * - LAST_ERROR_MESSAGE: message of last error
+ *
+ * Note: current policy is to apply this only to the results of queries
+ * entered by the user, not queries generated by slash commands.
+ */
+static void
+SetResultVariables(PGresult *result, bool success)
+{
+ if (success)
+ {
+ const char *ntuples = PQcmdTuples(result);
+
+ SetVariable(pset.vars, "ERROR", "false");
+ SetVariable(pset.vars, "SQLSTATE", "00000");
+ SetVariable(pset.vars, "ROW_COUNT", *ntuples ? ntuples : "0");
+ }
+ else
+ {
+ const char *code = PQresultErrorField(result, PG_DIAG_SQLSTATE);
+ const char *mesg = PQresultErrorField(result, PG_DIAG_MESSAGE_PRIMARY);
+
+ SetVariable(pset.vars, "ERROR", "true");
+
+ /*
+ * If there is no SQLSTATE code, use an empty string. This can happen
+ * for libpq-detected errors (e.g., lost connection, ENOMEM).
+ */
+ if (code == NULL)
+ code = "";
+ SetVariable(pset.vars, "SQLSTATE", code);
+ SetVariable(pset.vars, "ROW_COUNT", "0");
+ SetVariable(pset.vars, "LAST_ERROR_SQLSTATE", code);
+ SetVariable(pset.vars, "LAST_ERROR_MESSAGE", mesg ? mesg : "");
+ }
+}
+
+
+/*
+ * ClearOrSaveResult
+ *
+ * If the result represents an error, remember it for possible display by
+ * \errverbose. Otherwise, just PQclear() it.
+ *
+ * Note: current policy is to apply this to the results of all queries,
+ * including "back door" queries, for debugging's sake. It's OK to use
+ * PQclear() directly on results known to not be error results, however.
+ */
+static void
+ClearOrSaveResult(PGresult *result)
+{
+ if (result)
+ {
+ switch (PQresultStatus(result))
+ {
+ case PGRES_NONFATAL_ERROR:
+ case PGRES_FATAL_ERROR:
+ if (pset.last_error_result)
+ PQclear(pset.last_error_result);
+ pset.last_error_result = result;
+ break;
+
+ default:
+ PQclear(result);
+ break;
+ }
+ }
+}
+
+
+/*
+ * Consume all results
+ */
+static void
+ClearOrSaveAllResults(void)
+{
+ PGresult *result;
+
+ while ((result = PQgetResult(pset.db)) != NULL)
+ ClearOrSaveResult(result);
+}
+
+
+/*
+ * Print microtiming output. Always print raw milliseconds; if the interval
+ * is >= 1 second, also break it down into days/hours/minutes/seconds.
+ */
+static void
+PrintTiming(double elapsed_msec)
+{
+ double seconds;
+ double minutes;
+ double hours;
+ double days;
+
+ if (elapsed_msec < 1000.0)
+ {
+ /* This is the traditional (pre-v10) output format */
+ printf(_("Time: %.3f ms\n"), elapsed_msec);
+ return;
+ }
+
+ /*
+ * Note: we could print just seconds, in a format like %06.3f, when the
+ * total is less than 1min. But that's hard to interpret unless we tack
+ * on "s" or otherwise annotate it. Forcing the display to include
+ * minutes seems like a better solution.
+ */
+ seconds = elapsed_msec / 1000.0;
+ minutes = floor(seconds / 60.0);
+ seconds -= 60.0 * minutes;
+ if (minutes < 60.0)
+ {
+ printf(_("Time: %.3f ms (%02d:%06.3f)\n"),
+ elapsed_msec, (int) minutes, seconds);
+ return;
+ }
+
+ hours = floor(minutes / 60.0);
+ minutes -= 60.0 * hours;
+ if (hours < 24.0)
+ {
+ printf(_("Time: %.3f ms (%02d:%02d:%06.3f)\n"),
+ elapsed_msec, (int) hours, (int) minutes, seconds);
+ return;
+ }
+
+ days = floor(hours / 24.0);
+ hours -= 24.0 * days;
+ printf(_("Time: %.3f ms (%.0f d %02d:%02d:%06.3f)\n"),
+ elapsed_msec, days, (int) hours, (int) minutes, seconds);
+}
+
+
+/*
+ * PSQLexec
+ *
+ * This is the way to send "backdoor" queries (those not directly entered
+ * by the user). It is subject to -E but not -e.
+ *
+ * Caller is responsible for handling the ensuing processing if a COPY
+ * command is sent.
+ *
+ * Note: we don't bother to check PQclientEncoding; it is assumed that no
+ * caller uses this path to issue "SET CLIENT_ENCODING".
+ */
+PGresult *
+PSQLexec(const char *query)
+{
+ PGresult *res;
+
+ if (!pset.db)
+ {
+ pg_log_error("You are currently not connected to a database.");
+ return NULL;
+ }
+
+ if (pset.echo_hidden != PSQL_ECHO_HIDDEN_OFF)
+ {
+ printf(_("********* QUERY **********\n"
+ "%s\n"
+ "**************************\n\n"), query);
+ fflush(stdout);
+ if (pset.logfile)
+ {
+ fprintf(pset.logfile,
+ _("********* QUERY **********\n"
+ "%s\n"
+ "**************************\n\n"), query);
+ fflush(pset.logfile);
+ }
+
+ if (pset.echo_hidden == PSQL_ECHO_HIDDEN_NOEXEC)
+ return NULL;
+ }
+
+ SetCancelConn(pset.db);
+
+ res = PQexec(pset.db, query);
+
+ ResetCancelConn();
+
+ if (!AcceptResult(res, true))
+ {
+ ClearOrSaveResult(res);
+ res = NULL;
+ }
+
+ return res;
+}
+
+
+/*
+ * PSQLexecWatch
+ *
+ * This function is used for \watch command to send the query to
+ * the server and print out the result.
+ *
+ * Returns 1 if the query executed successfully, 0 if it cannot be repeated,
+ * e.g., because of the interrupt, -1 on error.
+ */
+int
+PSQLexecWatch(const char *query, const printQueryOpt *opt, FILE *printQueryFout)
+{
+ bool timing = pset.timing;
+ double elapsed_msec = 0;
+ int res;
+
+ if (!pset.db)
+ {
+ pg_log_error("You are currently not connected to a database.");
+ return 0;
+ }
+
+ SetCancelConn(pset.db);
+
+ res = ExecQueryAndProcessResults(query, &elapsed_msec, NULL, true, opt, printQueryFout);
+
+ ResetCancelConn();
+
+ /* Possible microtiming output */
+ if (timing)
+ PrintTiming(elapsed_msec);
+
+ return res;
+}
+
+
+/*
+ * PrintNotifications: check for asynchronous notifications, and print them out
+ */
+static void
+PrintNotifications(void)
+{
+ PGnotify *notify;
+
+ PQconsumeInput(pset.db);
+ while ((notify = PQnotifies(pset.db)) != NULL)
+ {
+ /* for backward compatibility, only show payload if nonempty */
+ if (notify->extra[0])
+ fprintf(pset.queryFout, _("Asynchronous notification \"%s\" with payload \"%s\" received from server process with PID %d.\n"),
+ notify->relname, notify->extra, notify->be_pid);
+ else
+ fprintf(pset.queryFout, _("Asynchronous notification \"%s\" received from server process with PID %d.\n"),
+ notify->relname, notify->be_pid);
+ fflush(pset.queryFout);
+ PQfreemem(notify);
+ PQconsumeInput(pset.db);
+ }
+}
+
+
+/*
+ * PrintQueryTuples: assuming query result is OK, print its tuples
+ *
+ * We use the options given by opt unless that's NULL, in which case
+ * we use pset.popt.
+ *
+ * Output is to printQueryFout unless that's NULL, in which case
+ * we use pset.queryFout.
+ *
+ * Returns true if successful, false otherwise.
+ */
+static bool
+PrintQueryTuples(const PGresult *result, const printQueryOpt *opt,
+ FILE *printQueryFout)
+{
+ bool ok = true;
+ FILE *fout = printQueryFout ? printQueryFout : pset.queryFout;
+
+ printQuery(result, opt ? opt : &pset.popt, fout, false, pset.logfile);
+ fflush(fout);
+ if (ferror(fout))
+ {
+ pg_log_error("could not print result table: %m");
+ ok = false;
+ }
+
+ return ok;
+}
+
+
+/*
+ * StoreQueryTuple: assuming query result is OK, save data into variables
+ *
+ * Returns true if successful, false otherwise.
+ */
+static bool
+StoreQueryTuple(const PGresult *result)
+{
+ bool success = true;
+
+ if (PQntuples(result) < 1)
+ {
+ pg_log_error("no rows returned for \\gset");
+ success = false;
+ }
+ else if (PQntuples(result) > 1)
+ {
+ pg_log_error("more than one row returned for \\gset");
+ success = false;
+ }
+ else
+ {
+ int i;
+
+ for (i = 0; i < PQnfields(result); i++)
+ {
+ char *colname = PQfname(result, i);
+ char *varname;
+ char *value;
+
+ /* concatenate prefix and column name */
+ varname = psprintf("%s%s", pset.gset_prefix, colname);
+
+ if (VariableHasHook(pset.vars, varname))
+ {
+ pg_log_warning("attempt to \\gset into specially treated variable \"%s\" ignored",
+ varname);
+ continue;
+ }
+
+ if (!PQgetisnull(result, 0, i))
+ value = PQgetvalue(result, 0, i);
+ else
+ {
+ /* for NULL value, unset rather than set the variable */
+ value = NULL;
+ }
+
+ if (!SetVariable(pset.vars, varname, value))
+ {
+ free(varname);
+ success = false;
+ break;
+ }
+
+ free(varname);
+ }
+ }
+
+ return success;
+}
+
+
+/*
+ * ExecQueryTuples: assuming query result is OK, execute each query
+ * result field as a SQL statement
+ *
+ * Returns true if successful, false otherwise.
+ */
+static bool
+ExecQueryTuples(const PGresult *result)
+{
+ bool success = true;
+ int nrows = PQntuples(result);
+ int ncolumns = PQnfields(result);
+ int r,
+ c;
+
+ /*
+ * We must turn off gexec_flag to avoid infinite recursion. Note that
+ * this allows ExecQueryUsingCursor to be applied to the individual query
+ * results. SendQuery prevents it from being applied when fetching the
+ * queries-to-execute, because it can't handle recursion either.
+ */
+ pset.gexec_flag = false;
+
+ for (r = 0; r < nrows; r++)
+ {
+ for (c = 0; c < ncolumns; c++)
+ {
+ if (!PQgetisnull(result, r, c))
+ {
+ const char *query = PQgetvalue(result, r, c);
+
+ /* Abandon execution if cancel_pressed */
+ if (cancel_pressed)
+ goto loop_exit;
+
+ /*
+ * ECHO_ALL mode should echo these queries, but SendQuery
+ * assumes that MainLoop did that, so we have to do it here.
+ */
+ if (pset.echo == PSQL_ECHO_ALL && !pset.singlestep)
+ {
+ puts(query);
+ fflush(stdout);
+ }
+
+ if (!SendQuery(query))
+ {
+ /* Error - abandon execution if ON_ERROR_STOP */
+ success = false;
+ if (pset.on_error_stop)
+ goto loop_exit;
+ }
+ }
+ }
+ }
+
+loop_exit:
+
+ /*
+ * Restore state. We know gexec_flag was on, else we'd not be here. (We
+ * also know it'll get turned off at end of command, but that's not ours
+ * to do here.)
+ */
+ pset.gexec_flag = true;
+
+ /* Return true if all queries were successful */
+ return success;
+}
+
+
+/*
+ * Marshal the COPY data. Either path will get the
+ * connection out of its COPY state, then call PQresultStatus()
+ * once and report any error. Return whether all was ok.
+ *
+ * For COPY OUT, direct the output to copystream, or discard if that's NULL.
+ * For COPY IN, use pset.copyStream as data source if it's set,
+ * otherwise cur_cmd_source.
+ *
+ * Update *resultp if further processing is necessary; set to NULL otherwise.
+ * Return a result when queryFout can safely output a result status: on COPY
+ * IN, or on COPY OUT if written to something other than pset.queryFout.
+ * Returning NULL prevents the command status from being printed, which we
+ * want if the status line doesn't get taken as part of the COPY data.
+ */
+static bool
+HandleCopyResult(PGresult **resultp, FILE *copystream)
+{
+ bool success;
+ PGresult *copy_result;
+ ExecStatusType result_status = PQresultStatus(*resultp);
+
+ Assert(result_status == PGRES_COPY_OUT ||
+ result_status == PGRES_COPY_IN);
+
+ SetCancelConn(pset.db);
+
+ if (result_status == PGRES_COPY_OUT)
+ {
+ success = handleCopyOut(pset.db,
+ copystream,
+ &copy_result)
+ && (copystream != NULL);
+
+ /*
+ * Suppress status printing if the report would go to the same place
+ * as the COPY data just went. Note this doesn't prevent error
+ * reporting, since handleCopyOut did that.
+ */
+ if (copystream == pset.queryFout)
+ {
+ PQclear(copy_result);
+ copy_result = NULL;
+ }
+ }
+ else
+ {
+ /* COPY IN */
+ /* Ignore the copystream argument passed to the function */
+ copystream = pset.copyStream ? pset.copyStream : pset.cur_cmd_source;
+ success = handleCopyIn(pset.db,
+ copystream,
+ PQbinaryTuples(*resultp),
+ &copy_result);
+ }
+ ResetCancelConn();
+
+ /*
+ * Replace the PGRES_COPY_OUT/IN result with COPY command's exit status,
+ * or with NULL if we want to suppress printing anything.
+ */
+ PQclear(*resultp);
+ *resultp = copy_result;
+
+ return success;
+}
+
+/*
+ * PrintQueryStatus: report command status as required
+ *
+ * Note: Utility function for use by PrintQueryResult() only.
+ */
+static void
+PrintQueryStatus(PGresult *result, FILE *printQueryFout)
+{
+ char buf[16];
+ FILE *fout = printQueryFout ? printQueryFout : pset.queryFout;
+
+ if (!pset.quiet)
+ {
+ if (pset.popt.topt.format == PRINT_HTML)
+ {
+ fputs("<p>", fout);
+ html_escaped_print(PQcmdStatus(result), fout);
+ fputs("</p>\n", fout);
+ }
+ else
+ fprintf(fout, "%s\n", PQcmdStatus(result));
+ fflush(fout);
+ }
+
+ if (pset.logfile)
+ fprintf(pset.logfile, "%s\n", PQcmdStatus(result));
+
+ snprintf(buf, sizeof(buf), "%u", (unsigned int) PQoidValue(result));
+ SetVariable(pset.vars, "LASTOID", buf);
+}
+
+
+/*
+ * PrintQueryResult: print out (or store or execute) query result as required
+ *
+ * Note: Utility function for use by SendQuery() only.
+ *
+ * last is true if this is the last result of a command string.
+ * opt and printQueryFout are defined as for PrintQueryTuples.
+ * printStatusFout is where to send command status; NULL means pset.queryFout.
+ *
+ * Returns true if the query executed successfully, false otherwise.
+ */
+static bool
+PrintQueryResult(PGresult *result, bool last,
+ const printQueryOpt *opt, FILE *printQueryFout,
+ FILE *printStatusFout)
+{
+ bool success;
+ const char *cmdstatus;
+
+ if (!result)
+ return false;
+
+ switch (PQresultStatus(result))
+ {
+ case PGRES_TUPLES_OK:
+ /* store or execute or print the data ... */
+ if (last && pset.gset_prefix)
+ success = StoreQueryTuple(result);
+ else if (last && pset.gexec_flag)
+ success = ExecQueryTuples(result);
+ else if (last && pset.crosstab_flag)
+ success = PrintResultInCrosstab(result);
+ else if (last || pset.show_all_results)
+ success = PrintQueryTuples(result, opt, printQueryFout);
+ else
+ success = true;
+
+ /* if it's INSERT/UPDATE/DELETE RETURNING, also print status */
+ if (last || pset.show_all_results)
+ {
+ cmdstatus = PQcmdStatus(result);
+ if (strncmp(cmdstatus, "INSERT", 6) == 0 ||
+ strncmp(cmdstatus, "UPDATE", 6) == 0 ||
+ strncmp(cmdstatus, "DELETE", 6) == 0)
+ PrintQueryStatus(result, printStatusFout);
+ }
+
+ break;
+
+ case PGRES_COMMAND_OK:
+ if (last || pset.show_all_results)
+ PrintQueryStatus(result, printStatusFout);
+ success = true;
+ break;
+
+ case PGRES_EMPTY_QUERY:
+ success = true;
+ break;
+
+ case PGRES_COPY_OUT:
+ case PGRES_COPY_IN:
+ /* nothing to do here: already processed */
+ success = true;
+ break;
+
+ case PGRES_BAD_RESPONSE:
+ case PGRES_NONFATAL_ERROR:
+ case PGRES_FATAL_ERROR:
+ success = false;
+ break;
+
+ default:
+ success = false;
+ pg_log_error("unexpected PQresultStatus: %d",
+ PQresultStatus(result));
+ break;
+ }
+
+ return success;
+}
+
+/*
+ * SendQuery: send the query string to the backend
+ * (and print out result)
+ *
+ * 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)
+{
+ bool timing = pset.timing;
+ PGTransactionStatusType transaction_status;
+ double elapsed_msec = 0;
+ bool OK = false;
+ int i;
+ bool on_error_rollback_savepoint = false;
+ bool svpt_gone = false;
+
+ if (!pset.db)
+ {
+ pg_log_error("You are currently not connected to a database.");
+ goto sendquery_cleanup;
+ }
+
+ if (pset.singlestep)
+ {
+ char buf[3];
+
+ fflush(stderr);
+ printf(_("***(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')
+ goto sendquery_cleanup;
+ if (cancel_pressed)
+ goto sendquery_cleanup;
+ }
+ else if (pset.echo == PSQL_ECHO_QUERIES)
+ {
+ puts(query);
+ fflush(stdout);
+ }
+
+ if (pset.logfile)
+ {
+ fprintf(pset.logfile,
+ _("********* QUERY **********\n"
+ "%s\n"
+ "**************************\n\n"), query);
+ fflush(pset.logfile);
+ }
+
+ SetCancelConn(pset.db);
+
+ transaction_status = PQtransactionStatus(pset.db);
+
+ if (transaction_status == PQTRANS_IDLE &&
+ !pset.autocommit &&
+ !command_no_begin(query))
+ {
+ PGresult *result;
+
+ result = PQexec(pset.db, "BEGIN");
+ if (PQresultStatus(result) != PGRES_COMMAND_OK)
+ {
+ pg_log_info("%s", PQerrorMessage(pset.db));
+ ClearOrSaveResult(result);
+ goto sendquery_cleanup;
+ }
+ ClearOrSaveResult(result);
+ transaction_status = PQtransactionStatus(pset.db);
+ }
+
+ if (transaction_status == PQTRANS_INTRANS &&
+ pset.on_error_rollback != PSQL_ERROR_ROLLBACK_OFF &&
+ (pset.cur_cmd_interactive ||
+ pset.on_error_rollback == PSQL_ERROR_ROLLBACK_ON))
+ {
+ PGresult *result;
+
+ result = PQexec(pset.db, "SAVEPOINT pg_psql_temporary_savepoint");
+ if (PQresultStatus(result) != PGRES_COMMAND_OK)
+ {
+ pg_log_info("%s", PQerrorMessage(pset.db));
+ ClearOrSaveResult(result);
+ goto sendquery_cleanup;
+ }
+ ClearOrSaveResult(result);
+ on_error_rollback_savepoint = true;
+ }
+
+ if (pset.gdesc_flag)
+ {
+ /* Describe query's result columns, without executing it */
+ OK = DescribeQuery(query, &elapsed_msec);
+ }
+ else if (pset.fetch_count <= 0 || pset.gexec_flag ||
+ pset.crosstab_flag || !is_select_command(query))
+ {
+ /* Default fetch-it-all-and-print mode */
+ OK = (ExecQueryAndProcessResults(query, &elapsed_msec, &svpt_gone, false, NULL, NULL) > 0);
+ }
+ else
+ {
+ /* Fetch-in-segments mode */
+ OK = ExecQueryUsingCursor(query, &elapsed_msec);
+ }
+
+ if (!OK && pset.echo == PSQL_ECHO_ERRORS)
+ pg_log_info("STATEMENT: %s", query);
+
+ /* If we made a temporary savepoint, possibly release/rollback */
+ if (on_error_rollback_savepoint)
+ {
+ const char *svptcmd = NULL;
+
+ transaction_status = PQtransactionStatus(pset.db);
+
+ switch (transaction_status)
+ {
+ case PQTRANS_INERROR:
+ /* We always rollback on an error */
+ svptcmd = "ROLLBACK TO pg_psql_temporary_savepoint";
+ break;
+
+ case PQTRANS_IDLE:
+ /* If they are no longer in a transaction, then do nothing */
+ break;
+
+ case PQTRANS_INTRANS:
+
+ /*
+ * Release our savepoint, but do nothing if they are messing
+ * with savepoints themselves
+ */
+ if (!svpt_gone)
+ svptcmd = "RELEASE pg_psql_temporary_savepoint";
+ break;
+
+ case PQTRANS_ACTIVE:
+ case PQTRANS_UNKNOWN:
+ default:
+ OK = false;
+ /* PQTRANS_UNKNOWN is expected given a broken connection. */
+ if (transaction_status != PQTRANS_UNKNOWN || ConnectionUp())
+ pg_log_error("unexpected transaction status (%d)",
+ transaction_status);
+ break;
+ }
+
+ if (svptcmd)
+ {
+ PGresult *svptres;
+
+ svptres = PQexec(pset.db, svptcmd);
+ if (PQresultStatus(svptres) != PGRES_COMMAND_OK)
+ {
+ pg_log_info("%s", PQerrorMessage(pset.db));
+ ClearOrSaveResult(svptres);
+ OK = false;
+
+ goto sendquery_cleanup;
+ }
+ PQclear(svptres);
+ }
+ }
+
+ /* Possible microtiming output */
+ if (timing)
+ PrintTiming(elapsed_msec);
+
+ /* 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();
+
+ /* perform cleanup that should occur after any attempted query */
+
+sendquery_cleanup:
+
+ /* global cancellation reset */
+ ResetCancelConn();
+
+ /* reset \g's output-to-filename trigger */
+ if (pset.gfname)
+ {
+ free(pset.gfname);
+ pset.gfname = NULL;
+ }
+
+ /* restore print settings if \g changed them */
+ if (pset.gsavepopt)
+ {
+ restorePsetInfo(&pset.popt, pset.gsavepopt);
+ pset.gsavepopt = NULL;
+ }
+
+ /* reset \gset trigger */
+ if (pset.gset_prefix)
+ {
+ free(pset.gset_prefix);
+ pset.gset_prefix = NULL;
+ }
+
+ /* reset \gdesc trigger */
+ pset.gdesc_flag = false;
+
+ /* reset \gexec trigger */
+ pset.gexec_flag = false;
+
+ /* reset \crosstabview trigger */
+ pset.crosstab_flag = false;
+ for (i = 0; i < lengthof(pset.ctv_args); i++)
+ {
+ pg_free(pset.ctv_args[i]);
+ pset.ctv_args[i] = NULL;
+ }
+
+ return OK;
+}
+
+
+/*
+ * DescribeQuery: describe the result columns of a query, without executing it
+ *
+ * Returns true if the operation executed successfully, false otherwise.
+ *
+ * If pset.timing is on, total query time (exclusive of result-printing) is
+ * stored into *elapsed_msec.
+ */
+static bool
+DescribeQuery(const char *query, double *elapsed_msec)
+{
+ bool timing = pset.timing;
+ PGresult *result;
+ bool OK;
+ instr_time before,
+ after;
+
+ *elapsed_msec = 0;
+
+ if (timing)
+ INSTR_TIME_SET_CURRENT(before);
+
+ /*
+ * To parse the query but not execute it, we prepare it, using the unnamed
+ * prepared statement. This is invisible to psql users, since there's no
+ * way to access the unnamed prepared statement from psql user space. The
+ * next Parse or Query protocol message would overwrite the statement
+ * anyway. (So there's no great need to clear it when done, which is a
+ * good thing because libpq provides no easy way to do that.)
+ */
+ result = PQprepare(pset.db, "", query, 0, NULL);
+ if (PQresultStatus(result) != PGRES_COMMAND_OK)
+ {
+ pg_log_info("%s", PQerrorMessage(pset.db));
+ SetResultVariables(result, false);
+ ClearOrSaveResult(result);
+ return false;
+ }
+ PQclear(result);
+
+ result = PQdescribePrepared(pset.db, "");
+ OK = AcceptResult(result, true) &&
+ (PQresultStatus(result) == PGRES_COMMAND_OK);
+ if (OK && result)
+ {
+ if (PQnfields(result) > 0)
+ {
+ PQExpBufferData buf;
+ int i;
+
+ initPQExpBuffer(&buf);
+
+ printfPQExpBuffer(&buf,
+ "SELECT name AS \"%s\", pg_catalog.format_type(tp, tpm) AS \"%s\"\n"
+ "FROM (VALUES ",
+ gettext_noop("Column"),
+ gettext_noop("Type"));
+
+ for (i = 0; i < PQnfields(result); i++)
+ {
+ const char *name;
+ char *escname;
+
+ if (i > 0)
+ appendPQExpBufferStr(&buf, ",");
+
+ name = PQfname(result, i);
+ escname = PQescapeLiteral(pset.db, name, strlen(name));
+
+ if (escname == NULL)
+ {
+ pg_log_info("%s", PQerrorMessage(pset.db));
+ PQclear(result);
+ termPQExpBuffer(&buf);
+ return false;
+ }
+
+ appendPQExpBuffer(&buf, "(%s, '%u'::pg_catalog.oid, %d)",
+ escname,
+ PQftype(result, i),
+ PQfmod(result, i));
+
+ PQfreemem(escname);
+ }
+
+ appendPQExpBufferStr(&buf, ") s(name, tp, tpm)");
+ PQclear(result);
+
+ result = PQexec(pset.db, buf.data);
+ OK = AcceptResult(result, true);
+
+ if (timing)
+ {
+ INSTR_TIME_SET_CURRENT(after);
+ INSTR_TIME_SUBTRACT(after, before);
+ *elapsed_msec += INSTR_TIME_GET_MILLISEC(after);
+ }
+
+ if (OK && result)
+ OK = PrintQueryResult(result, true, NULL, NULL, NULL);
+
+ termPQExpBuffer(&buf);
+ }
+ else
+ fprintf(pset.queryFout,
+ _("The command has no result, or the result has no columns.\n"));
+ }
+
+ SetResultVariables(result, OK);
+ ClearOrSaveResult(result);
+
+ return OK;
+}
+
+
+/*
+ * ExecQueryAndProcessResults: utility function for use by SendQuery()
+ * and PSQLexecWatch().
+ *
+ * Sends query and cycles through PGresult objects.
+ *
+ * If our command string contained a COPY FROM STDIN or COPY TO STDOUT, the
+ * PGresult associated with these commands must be processed by providing an
+ * input or output stream. In that event, we'll marshal data for the COPY.
+ *
+ * For other commands, the results are processed normally, depending on their
+ * status.
+ *
+ * Returns 1 on complete success, 0 on interrupt and -1 or errors. Possible
+ * failure modes include purely client-side problems; check the transaction
+ * status for the server-side opinion.
+ *
+ * Note that on a combined query, failure does not mean that nothing was
+ * committed.
+ */
+static int
+ExecQueryAndProcessResults(const char *query,
+ double *elapsed_msec, bool *svpt_gone_p,
+ bool is_watch,
+ const printQueryOpt *opt, FILE *printQueryFout)
+{
+ bool timing = pset.timing;
+ bool success;
+ instr_time before,
+ after;
+ PGresult *result;
+ FILE *gfile_fout = NULL;
+ bool gfile_is_pipe = false;
+
+ if (timing)
+ INSTR_TIME_SET_CURRENT(before);
+
+ success = PQsendQuery(pset.db, query);
+
+ if (!success)
+ {
+ const char *error = PQerrorMessage(pset.db);
+
+ if (strlen(error))
+ pg_log_info("%s", error);
+
+ CheckConnection();
+
+ return -1;
+ }
+
+ /*
+ * If SIGINT is sent while the query is processing, the interrupt will be
+ * consumed. The user's intention, though, is to cancel the entire watch
+ * process, so detect a sent cancellation request and exit in this case.
+ */
+ if (is_watch && cancel_pressed)
+ {
+ ClearOrSaveAllResults();
+ return 0;
+ }
+
+ /* first result */
+ result = PQgetResult(pset.db);
+
+ while (result != NULL)
+ {
+ ExecStatusType result_status;
+ PGresult *next_result;
+ bool last;
+
+ if (!AcceptResult(result, false))
+ {
+ /*
+ * Some error occured, either a server-side failure or a failure
+ * to submit the command string. Record that.
+ */
+ const char *error = PQresultErrorMessage(result);
+
+ if (strlen(error))
+ pg_log_info("%s", error);
+
+ CheckConnection();
+ if (!is_watch)
+ SetResultVariables(result, false);
+
+ /* keep the result status before clearing it */
+ result_status = PQresultStatus(result);
+ ClearOrSaveResult(result);
+ success = false;
+
+ /*
+ * switch to next result
+ */
+ if (result_status == PGRES_COPY_BOTH ||
+ result_status == PGRES_COPY_OUT ||
+ result_status == PGRES_COPY_IN)
+
+ /*
+ * For some obscure reason PQgetResult does *not* return a
+ * NULL in copy cases despite the result having been cleared,
+ * but keeps returning an "empty" result that we have to
+ * ignore manually.
+ */
+ result = NULL;
+ else
+ result = PQgetResult(pset.db);
+
+ /*
+ * Get current timing measure in case an error occurs
+ */
+ if (timing)
+ {
+ INSTR_TIME_SET_CURRENT(after);
+ INSTR_TIME_SUBTRACT(after, before);
+ *elapsed_msec = INSTR_TIME_GET_MILLISEC(after);
+ }
+
+ continue;
+ }
+ else if (svpt_gone_p && !*svpt_gone_p)
+ {
+ /*
+ * Check if the user ran any command that would destroy our
+ * internal savepoint: If the user did COMMIT AND CHAIN, RELEASE
+ * or ROLLBACK, our savepoint is gone. If they issued a SAVEPOINT,
+ * releasing ours would remove theirs.
+ */
+ const char *cmd = PQcmdStatus(result);
+
+ *svpt_gone_p = (strcmp(cmd, "COMMIT") == 0 ||
+ strcmp(cmd, "SAVEPOINT") == 0 ||
+ strcmp(cmd, "RELEASE") == 0 ||
+ strcmp(cmd, "ROLLBACK") == 0);
+ }
+
+ result_status = PQresultStatus(result);
+
+ /* must handle COPY before changing the current result */
+ Assert(result_status != PGRES_COPY_BOTH);
+ if (result_status == PGRES_COPY_IN ||
+ result_status == PGRES_COPY_OUT)
+ {
+ FILE *copy_stream = NULL;
+
+ /*
+ * For COPY OUT, direct the output to the default place (probably
+ * a pager pipe) for \watch, or to pset.copyStream for \copy,
+ * otherwise to pset.gfname if that's set, otherwise to
+ * pset.queryFout.
+ */
+ if (result_status == PGRES_COPY_OUT)
+ {
+ if (is_watch)
+ {
+ /* invoked by \watch */
+ copy_stream = printQueryFout ? printQueryFout : pset.queryFout;
+ }
+ else if (pset.copyStream)
+ {
+ /* invoked by \copy */
+ copy_stream = pset.copyStream;
+ }
+ else if (pset.gfname)
+ {
+ /* send to \g file, which we may have opened already */
+ if (gfile_fout == NULL)
+ {
+ if (openQueryOutputFile(pset.gfname,
+ &gfile_fout, &gfile_is_pipe))
+ {
+ if (gfile_is_pipe)
+ disable_sigpipe_trap();
+ copy_stream = gfile_fout;
+ }
+ else
+ success = false;
+ }
+ else
+ copy_stream = gfile_fout;
+ }
+ else
+ {
+ /* fall back to the generic query output stream */
+ copy_stream = pset.queryFout;
+ }
+ }
+
+ /*
+ * Even if the output stream could not be opened, we call
+ * HandleCopyResult() with a NULL output stream to collect and
+ * discard the COPY data.
+ */
+ success &= HandleCopyResult(&result, copy_stream);
+ }
+
+ /*
+ * Check PQgetResult() again. In the typical case of a single-command
+ * string, it will return NULL. Otherwise, we'll have other results
+ * to process. We need to do that to check whether this is the last.
+ */
+ next_result = PQgetResult(pset.db);
+ last = (next_result == NULL);
+
+ /*
+ * Update current timing measure.
+ *
+ * It will include the display of previous results, if any. This
+ * cannot be helped because the server goes on processing further
+ * queries anyway while the previous ones are being displayed. The
+ * parallel execution of the client display hides the server time when
+ * it is shorter.
+ *
+ * With combined queries, timing must be understood as an upper bound
+ * of the time spent processing them.
+ */
+ if (timing)
+ {
+ INSTR_TIME_SET_CURRENT(after);
+ INSTR_TIME_SUBTRACT(after, before);
+ *elapsed_msec = INSTR_TIME_GET_MILLISEC(after);
+ }
+
+ /* this may or may not print something depending on settings */
+ if (result != NULL)
+ {
+ /*
+ * If results need to be printed into the file specified by \g,
+ * open it, unless we already did. Note that when pset.gfname is
+ * set, the passed-in value of printQueryFout is not used for
+ * tuple output, but it's still used for status output.
+ */
+ FILE *tuples_fout = printQueryFout;
+ bool do_print = true;
+
+ if (PQresultStatus(result) == PGRES_TUPLES_OK &&
+ pset.gfname)
+ {
+ if (gfile_fout == NULL)
+ {
+ if (openQueryOutputFile(pset.gfname,
+ &gfile_fout, &gfile_is_pipe))
+ {
+ if (gfile_is_pipe)
+ disable_sigpipe_trap();
+ }
+ else
+ success = do_print = false;
+ }
+ tuples_fout = gfile_fout;
+ }
+ if (do_print)
+ success &= PrintQueryResult(result, last, opt,
+ tuples_fout, printQueryFout);
+ }
+
+ /* set variables on last result if all went well */
+ if (!is_watch && last && success)
+ SetResultVariables(result, true);
+
+ ClearOrSaveResult(result);
+ result = next_result;
+
+ if (cancel_pressed)
+ {
+ ClearOrSaveAllResults();
+ break;
+ }
+ }
+
+ /* close \g file if we opened it */
+ if (gfile_fout)
+ {
+ if (gfile_is_pipe)
+ {
+ pclose(gfile_fout);
+ restore_sigpipe_trap();
+ }
+ else
+ fclose(gfile_fout);
+ }
+
+ /* may need this to recover from conn loss during COPY */
+ if (!CheckConnection())
+ return -1;
+
+ return cancel_pressed ? 0 : success ? 1 : -1;
+}
+
+
+/*
+ * ExecQueryUsingCursor: run a SELECT-like query using a cursor
+ *
+ * This feature allows result sets larger than RAM to be dealt with.
+ *
+ * Returns true if the query executed successfully, false otherwise.
+ *
+ * If pset.timing is on, total query time (exclusive of result-printing) is
+ * stored into *elapsed_msec.
+ */
+static bool
+ExecQueryUsingCursor(const char *query, double *elapsed_msec)
+{
+ bool OK = true;
+ PGresult *result;
+ PQExpBufferData buf;
+ printQueryOpt my_popt = pset.popt;
+ bool timing = pset.timing;
+ FILE *fout;
+ bool is_pipe;
+ bool is_pager = false;
+ bool started_txn = false;
+ int64 total_tuples = 0;
+ int ntuples;
+ int fetch_count;
+ char fetch_cmd[64];
+ instr_time before,
+ after;
+ int flush_error;
+
+ *elapsed_msec = 0;
+
+ /* initialize print options for partial table output */
+ my_popt.topt.start_table = true;
+ my_popt.topt.stop_table = false;
+ my_popt.topt.prior_records = 0;
+
+ if (timing)
+ INSTR_TIME_SET_CURRENT(before);
+
+ /* if we're not in a transaction, start one */
+ if (PQtransactionStatus(pset.db) == PQTRANS_IDLE)
+ {
+ result = PQexec(pset.db, "BEGIN");
+ OK = AcceptResult(result, true) &&
+ (PQresultStatus(result) == PGRES_COMMAND_OK);
+ ClearOrSaveResult(result);
+ if (!OK)
+ return false;
+ started_txn = true;
+ }
+
+ /* Send DECLARE CURSOR */
+ initPQExpBuffer(&buf);
+ appendPQExpBuffer(&buf, "DECLARE _psql_cursor NO SCROLL CURSOR FOR\n%s",
+ query);
+
+ result = PQexec(pset.db, buf.data);
+ OK = AcceptResult(result, true) &&
+ (PQresultStatus(result) == PGRES_COMMAND_OK);
+ if (!OK)
+ SetResultVariables(result, OK);
+ ClearOrSaveResult(result);
+ termPQExpBuffer(&buf);
+ if (!OK)
+ goto cleanup;
+
+ if (timing)
+ {
+ INSTR_TIME_SET_CURRENT(after);
+ INSTR_TIME_SUBTRACT(after, before);
+ *elapsed_msec += INSTR_TIME_GET_MILLISEC(after);
+ }
+
+ /*
+ * In \gset mode, we force the fetch count to be 2, so that we will throw
+ * the appropriate error if the query returns more than one row.
+ */
+ if (pset.gset_prefix)
+ fetch_count = 2;
+ else
+ fetch_count = pset.fetch_count;
+
+ snprintf(fetch_cmd, sizeof(fetch_cmd),
+ "FETCH FORWARD %d FROM _psql_cursor",
+ fetch_count);
+
+ /* prepare to write output to \g argument, if any */
+ if (pset.gfname)
+ {
+ if (!openQueryOutputFile(pset.gfname, &fout, &is_pipe))
+ {
+ OK = false;
+ goto cleanup;
+ }
+ if (is_pipe)
+ disable_sigpipe_trap();
+ }
+ else
+ {
+ fout = pset.queryFout;
+ is_pipe = false; /* doesn't matter */
+ }
+
+ /* clear any pre-existing error indication on the output stream */
+ clearerr(fout);
+
+ for (;;)
+ {
+ if (timing)
+ INSTR_TIME_SET_CURRENT(before);
+
+ /* get fetch_count tuples at a time */
+ result = PQexec(pset.db, fetch_cmd);
+
+ if (timing)
+ {
+ INSTR_TIME_SET_CURRENT(after);
+ INSTR_TIME_SUBTRACT(after, before);
+ *elapsed_msec += INSTR_TIME_GET_MILLISEC(after);
+ }
+
+ if (PQresultStatus(result) != PGRES_TUPLES_OK)
+ {
+ /* shut down pager before printing error message */
+ if (is_pager)
+ {
+ ClosePager(fout);
+ is_pager = false;
+ }
+
+ OK = AcceptResult(result, true);
+ Assert(!OK);
+ SetResultVariables(result, OK);
+ ClearOrSaveResult(result);
+ break;
+ }
+
+ if (pset.gset_prefix)
+ {
+ /* StoreQueryTuple will complain if not exactly one row */
+ OK = StoreQueryTuple(result);
+ ClearOrSaveResult(result);
+ break;
+ }
+
+ /*
+ * Note we do not deal with \gdesc, \gexec or \crosstabview modes here
+ */
+
+ ntuples = PQntuples(result);
+ total_tuples += ntuples;
+
+ if (ntuples < fetch_count)
+ {
+ /* this is the last result set, so allow footer decoration */
+ my_popt.topt.stop_table = true;
+ }
+ else if (fout == stdout && !is_pager)
+ {
+ /*
+ * If query requires multiple result sets, hack to ensure that
+ * only one pager instance is used for the whole mess
+ */
+ fout = PageOutput(INT_MAX, &(my_popt.topt));
+ is_pager = true;
+ }
+
+ printQuery(result, &my_popt, fout, is_pager, pset.logfile);
+
+ ClearOrSaveResult(result);
+
+ /* after the first result set, disallow header decoration */
+ my_popt.topt.start_table = false;
+ my_popt.topt.prior_records += ntuples;
+
+ /*
+ * Make sure to flush the output stream, so intermediate results are
+ * visible to the client immediately. We check the results because if
+ * the pager dies/exits/etc, there's no sense throwing more data at
+ * it.
+ */
+ flush_error = fflush(fout);
+
+ /*
+ * Check if we are at the end, if a cancel was pressed, or if there
+ * were any errors either trying to flush out the results, or more
+ * generally on the output stream at all. If we hit any errors
+ * writing things to the stream, we presume $PAGER has disappeared and
+ * stop bothering to pull down more data.
+ */
+ if (ntuples < fetch_count || cancel_pressed || flush_error ||
+ ferror(fout))
+ break;
+ }
+
+ if (pset.gfname)
+ {
+ /* close \g argument file/pipe */
+ if (is_pipe)
+ {
+ pclose(fout);
+ restore_sigpipe_trap();
+ }
+ else
+ fclose(fout);
+ }
+ else if (is_pager)
+ {
+ /* close transient pager */
+ ClosePager(fout);
+ }
+
+ if (OK)
+ {
+ /*
+ * We don't have a PGresult here, and even if we did it wouldn't have
+ * the right row count, so fake SetResultVariables(). In error cases,
+ * we already set the result variables above.
+ */
+ char buf[32];
+
+ SetVariable(pset.vars, "ERROR", "false");
+ SetVariable(pset.vars, "SQLSTATE", "00000");
+ snprintf(buf, sizeof(buf), INT64_FORMAT, total_tuples);
+ SetVariable(pset.vars, "ROW_COUNT", buf);
+ }
+
+cleanup:
+ if (timing)
+ INSTR_TIME_SET_CURRENT(before);
+
+ /*
+ * We try to close the cursor on either success or failure, but on failure
+ * ignore the result (it's probably just a bleat about being in an aborted
+ * transaction)
+ */
+ result = PQexec(pset.db, "CLOSE _psql_cursor");
+ if (OK)
+ {
+ OK = AcceptResult(result, true) &&
+ (PQresultStatus(result) == PGRES_COMMAND_OK);
+ ClearOrSaveResult(result);
+ }
+ else
+ PQclear(result);
+
+ if (started_txn)
+ {
+ result = PQexec(pset.db, OK ? "COMMIT" : "ROLLBACK");
+ OK &= AcceptResult(result, true) &&
+ (PQresultStatus(result) == PGRES_COMMAND_OK);
+ ClearOrSaveResult(result);
+ }
+
+ if (timing)
+ {
+ INSTR_TIME_SET_CURRENT(after);
+ INSTR_TIME_SUBTRACT(after, before);
+ *elapsed_msec += INSTR_TIME_GET_MILLISEC(after);
+ }
+
+ return OK;
+}
+
+
+/*
+ * Advance the given char pointer over white space and SQL comments.
+ */
+static const char *
+skip_white_space(const char *query)
+{
+ int cnestlevel = 0; /* slash-star comment nest level */
+
+ while (*query)
+ {
+ int mblen = PQmblenBounded(query, pset.encoding);
+
+ /*
+ * Note: we assume the encoding is a superset of ASCII, so that for
+ * example "query[0] == '/'" is meaningful. However, we do NOT assume
+ * that the second and subsequent bytes of a multibyte character
+ * couldn't look like ASCII characters; so it is critical to advance
+ * by mblen, not 1, whenever we haven't exactly identified the
+ * character we are skipping over.
+ */
+ if (isspace((unsigned char) *query))
+ query += mblen;
+ else if (query[0] == '/' && query[1] == '*')
+ {
+ cnestlevel++;
+ query += 2;
+ }
+ else if (cnestlevel > 0 && query[0] == '*' && query[1] == '/')
+ {
+ cnestlevel--;
+ query += 2;
+ }
+ else if (cnestlevel == 0 && query[0] == '-' && query[1] == '-')
+ {
+ query += 2;
+
+ /*
+ * We have to skip to end of line since any slash-star inside the
+ * -- comment does NOT start a slash-star comment.
+ */
+ while (*query)
+ {
+ if (*query == '\n')
+ {
+ query++;
+ break;
+ }
+ query += PQmblenBounded(query, pset.encoding);
+ }
+ }
+ else if (cnestlevel > 0)
+ query += mblen;
+ else
+ break; /* found first token */
+ }
+
+ return query;
+}
+
+
+/*
+ * Check whether a command is one of those for which we should NOT start
+ * a new transaction block (ie, send a preceding BEGIN).
+ *
+ * These include the transaction control statements themselves, plus
+ * certain statements that the backend disallows inside transaction blocks.
+ */
+static bool
+command_no_begin(const char *query)
+{
+ int wordlen;
+
+ /*
+ * First we must advance over any whitespace and comments.
+ */
+ query = skip_white_space(query);
+
+ /*
+ * Check word length (since "beginx" is not "begin").
+ */
+ wordlen = 0;
+ while (isalpha((unsigned char) query[wordlen]))
+ wordlen += PQmblenBounded(&query[wordlen], pset.encoding);
+
+ /*
+ * Transaction control commands. These should include every keyword that
+ * gives rise to a TransactionStmt in the backend grammar, except for the
+ * savepoint-related commands.
+ *
+ * (We assume that START must be START TRANSACTION, since there is
+ * presently no other "START foo" command.)
+ */
+ if (wordlen == 5 && pg_strncasecmp(query, "abort", 5) == 0)
+ return true;
+ if (wordlen == 5 && pg_strncasecmp(query, "begin", 5) == 0)
+ return true;
+ if (wordlen == 5 && pg_strncasecmp(query, "start", 5) == 0)
+ return true;
+ if (wordlen == 6 && pg_strncasecmp(query, "commit", 6) == 0)
+ return true;
+ if (wordlen == 3 && pg_strncasecmp(query, "end", 3) == 0)
+ return true;
+ if (wordlen == 8 && pg_strncasecmp(query, "rollback", 8) == 0)
+ return true;
+ if (wordlen == 7 && pg_strncasecmp(query, "prepare", 7) == 0)
+ {
+ /* PREPARE TRANSACTION is a TC command, PREPARE foo is not */
+ query += wordlen;
+
+ query = skip_white_space(query);
+
+ wordlen = 0;
+ while (isalpha((unsigned char) query[wordlen]))
+ wordlen += PQmblenBounded(&query[wordlen], pset.encoding);
+
+ if (wordlen == 11 && pg_strncasecmp(query, "transaction", 11) == 0)
+ return true;
+ return false;
+ }
+
+ /*
+ * Commands not allowed within transactions. The statements checked for
+ * here should be exactly those that call PreventInTransactionBlock() in
+ * the backend.
+ */
+ if (wordlen == 6 && pg_strncasecmp(query, "vacuum", 6) == 0)
+ return true;
+ if (wordlen == 7 && pg_strncasecmp(query, "cluster", 7) == 0)
+ {
+ /* CLUSTER with any arguments is allowed in transactions */
+ query += wordlen;
+
+ query = skip_white_space(query);
+
+ if (isalpha((unsigned char) query[0]))
+ return false; /* has additional words */
+ return true; /* it's CLUSTER without arguments */
+ }
+
+ if (wordlen == 6 && pg_strncasecmp(query, "create", 6) == 0)
+ {
+ query += wordlen;
+
+ query = skip_white_space(query);
+
+ wordlen = 0;
+ while (isalpha((unsigned char) query[wordlen]))
+ wordlen += PQmblenBounded(&query[wordlen], pset.encoding);
+
+ if (wordlen == 8 && pg_strncasecmp(query, "database", 8) == 0)
+ return true;
+ if (wordlen == 10 && pg_strncasecmp(query, "tablespace", 10) == 0)
+ return true;
+
+ /* CREATE [UNIQUE] INDEX CONCURRENTLY isn't allowed in xacts */
+ if (wordlen == 6 && pg_strncasecmp(query, "unique", 6) == 0)
+ {
+ query += wordlen;
+
+ query = skip_white_space(query);
+
+ wordlen = 0;
+ while (isalpha((unsigned char) query[wordlen]))
+ wordlen += PQmblenBounded(&query[wordlen], pset.encoding);
+ }
+
+ if (wordlen == 5 && pg_strncasecmp(query, "index", 5) == 0)
+ {
+ query += wordlen;
+
+ query = skip_white_space(query);
+
+ wordlen = 0;
+ while (isalpha((unsigned char) query[wordlen]))
+ wordlen += PQmblenBounded(&query[wordlen], pset.encoding);
+
+ if (wordlen == 12 && pg_strncasecmp(query, "concurrently", 12) == 0)
+ return true;
+ }
+
+ return false;
+ }
+
+ if (wordlen == 5 && pg_strncasecmp(query, "alter", 5) == 0)
+ {
+ query += wordlen;
+
+ query = skip_white_space(query);
+
+ wordlen = 0;
+ while (isalpha((unsigned char) query[wordlen]))
+ wordlen += PQmblenBounded(&query[wordlen], pset.encoding);
+
+ /* ALTER SYSTEM isn't allowed in xacts */
+ if (wordlen == 6 && pg_strncasecmp(query, "system", 6) == 0)
+ return true;
+
+ return false;
+ }
+
+ /*
+ * Note: these tests will match DROP SYSTEM and REINDEX TABLESPACE, which
+ * aren't really valid commands so we don't care much. The other four
+ * possible matches are correct.
+ */
+ if ((wordlen == 4 && pg_strncasecmp(query, "drop", 4) == 0) ||
+ (wordlen == 7 && pg_strncasecmp(query, "reindex", 7) == 0))
+ {
+ query += wordlen;
+
+ query = skip_white_space(query);
+
+ wordlen = 0;
+ while (isalpha((unsigned char) query[wordlen]))
+ wordlen += PQmblenBounded(&query[wordlen], pset.encoding);
+
+ if (wordlen == 8 && pg_strncasecmp(query, "database", 8) == 0)
+ return true;
+ if (wordlen == 6 && pg_strncasecmp(query, "system", 6) == 0)
+ return true;
+ if (wordlen == 10 && pg_strncasecmp(query, "tablespace", 10) == 0)
+ return true;
+ if (wordlen == 5 && (pg_strncasecmp(query, "index", 5) == 0 ||
+ pg_strncasecmp(query, "table", 5) == 0))
+ {
+ query += wordlen;
+ query = skip_white_space(query);
+ wordlen = 0;
+ while (isalpha((unsigned char) query[wordlen]))
+ wordlen += PQmblenBounded(&query[wordlen], pset.encoding);
+
+ /*
+ * REINDEX [ TABLE | INDEX ] CONCURRENTLY are not allowed in
+ * xacts.
+ */
+ if (wordlen == 12 && pg_strncasecmp(query, "concurrently", 12) == 0)
+ return true;
+ }
+
+ /* DROP INDEX CONCURRENTLY isn't allowed in xacts */
+ if (wordlen == 5 && pg_strncasecmp(query, "index", 5) == 0)
+ {
+ query += wordlen;
+
+ query = skip_white_space(query);
+
+ wordlen = 0;
+ while (isalpha((unsigned char) query[wordlen]))
+ wordlen += PQmblenBounded(&query[wordlen], pset.encoding);
+
+ if (wordlen == 12 && pg_strncasecmp(query, "concurrently", 12) == 0)
+ return true;
+
+ return false;
+ }
+
+ return false;
+ }
+
+ /* DISCARD ALL isn't allowed in xacts, but other variants are allowed. */
+ if (wordlen == 7 && pg_strncasecmp(query, "discard", 7) == 0)
+ {
+ query += wordlen;
+
+ query = skip_white_space(query);
+
+ wordlen = 0;
+ while (isalpha((unsigned char) query[wordlen]))
+ wordlen += PQmblenBounded(&query[wordlen], pset.encoding);
+
+ if (wordlen == 3 && pg_strncasecmp(query, "all", 3) == 0)
+ return true;
+ return false;
+ }
+
+ return false;
+}
+
+
+/*
+ * Check whether the specified command is a SELECT (or VALUES).
+ */
+static bool
+is_select_command(const char *query)
+{
+ int wordlen;
+
+ /*
+ * First advance over any whitespace, comments and left parentheses.
+ */
+ for (;;)
+ {
+ query = skip_white_space(query);
+ if (query[0] == '(')
+ query++;
+ else
+ break;
+ }
+
+ /*
+ * Check word length (since "selectx" is not "select").
+ */
+ wordlen = 0;
+ while (isalpha((unsigned char) query[wordlen]))
+ wordlen += PQmblenBounded(&query[wordlen], pset.encoding);
+
+ if (wordlen == 6 && pg_strncasecmp(query, "select", 6) == 0)
+ return true;
+
+ if (wordlen == 6 && pg_strncasecmp(query, "values", 6) == 0)
+ return true;
+
+ return false;
+}
+
+
+/*
+ * Test if the current user is a database superuser.
+ */
+bool
+is_superuser(void)
+{
+ const char *val;
+
+ if (!pset.db)
+ return false;
+
+ val = PQparameterStatus(pset.db, "is_superuser");
+
+ if (val && strcmp(val, "on") == 0)
+ return true;
+
+ return false;
+}
+
+
+/*
+ * Test if the current session uses standard string literals.
+ */
+bool
+standard_strings(void)
+{
+ const char *val;
+
+ if (!pset.db)
+ return false;
+
+ val = PQparameterStatus(pset.db, "standard_conforming_strings");
+
+ if (val && strcmp(val, "on") == 0)
+ return true;
+
+ return false;
+}
+
+
+/*
+ * Return the session user of the current connection.
+ */
+const char *
+session_username(void)
+{
+ const char *val;
+
+ if (!pset.db)
+ return NULL;
+
+ val = PQparameterStatus(pset.db, "session_authorization");
+ if (val)
+ return val;
+ else
+ return PQuser(pset.db);
+}
+
+
+/* expand_tilde
+ *
+ * substitute '~' with HOME or '~username' with username's home dir
+ *
+ */
+void
+expand_tilde(char **filename)
+{
+ if (!filename || !(*filename))
+ return;
+
+ /*
+ * WIN32 doesn't use tilde expansion for file names. Also, it uses tilde
+ * for short versions of long file names, though the tilde is usually
+ * toward the end, not at the beginning.
+ */
+#ifndef WIN32
+
+ /* try tilde expansion */
+ if (**filename == '~')
+ {
+ char *fn;
+ char oldp,
+ *p;
+ struct passwd *pw;
+ char home[MAXPGPATH];
+
+ fn = *filename;
+ *home = '\0';
+
+ p = fn + 1;
+ while (*p != '/' && *p != '\0')
+ p++;
+
+ oldp = *p;
+ *p = '\0';
+
+ if (*(fn + 1) == '\0')
+ get_home_path(home); /* ~ or ~/ only */
+ else if ((pw = getpwnam(fn + 1)) != NULL)
+ strlcpy(home, pw->pw_dir, sizeof(home)); /* ~user */
+
+ *p = oldp;
+ if (strlen(home) != 0)
+ {
+ char *newfn;
+
+ newfn = psprintf("%s%s", home, p);
+ free(fn);
+ *filename = newfn;
+ }
+ }
+#endif
+}
+
+/*
+ * Checks if connection string starts with either of the valid URI prefix
+ * designators.
+ *
+ * Returns the URI prefix length, 0 if the string doesn't contain a URI prefix.
+ *
+ * XXX This is a duplicate of the eponymous libpq function.
+ */
+static int
+uri_prefix_length(const char *connstr)
+{
+ /* The connection URI must start with either of the following designators: */
+ static const char uri_designator[] = "postgresql://";
+ static const char short_uri_designator[] = "postgres://";
+
+ if (strncmp(connstr, uri_designator,
+ sizeof(uri_designator) - 1) == 0)
+ return sizeof(uri_designator) - 1;
+
+ if (strncmp(connstr, short_uri_designator,
+ sizeof(short_uri_designator) - 1) == 0)
+ return sizeof(short_uri_designator) - 1;
+
+ return 0;
+}
+
+/*
+ * Recognized connection string either starts with a valid URI prefix or
+ * contains a "=" in it.
+ *
+ * Must be consistent with parse_connection_string: anything for which this
+ * returns true should at least look like it's parseable by that routine.
+ *
+ * XXX This is a duplicate of the eponymous libpq function.
+ */
+bool
+recognized_connection_string(const char *connstr)
+{
+ return uri_prefix_length(connstr) != 0 || strchr(connstr, '=') != NULL;
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-20 16:51:53 +0000