Adding upstream version 13.4.upstream/13.4upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 478 insertions, 0 deletions

diff --git a/src/bin/scripts/common.c b/src/bin/scripts/common.c
new file mode 100644
index 0000000..d446d7a
--- /dev/null
+++ b/src/bin/scripts/common.c
@@ -0,0 +1,478 @@
+/*-------------------------------------------------------------------------
+ *
+ *	common.c
+ *		Common support routines for bin/scripts/
+ *
+ *
+ * Portions Copyright (c) 1996-2020, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1994, Regents of the University of California
+ *
+ * src/bin/scripts/common.c
+ *
+ *-------------------------------------------------------------------------
+ */
+
+#include "postgres_fe.h"
+
+#include <signal.h>
+#include <unistd.h>
+
+#include "common.h"
+#include "common/connect.h"
+#include "common/logging.h"
+#include "fe_utils/cancel.h"
+#include "fe_utils/string_utils.h"
+
+#define ERRCODE_UNDEFINED_TABLE  "42P01"
+
+#define PQmblenBounded(s, e)  strnlen(s, PQmblen(s, e))
+
+/*
+ * Provide strictly harmonized handling of --help and --version
+ * options.
+ */
+void
+handle_help_version_opts(int argc, char *argv[],
+						 const char *fixed_progname, help_handler hlp)
+{
+	if (argc > 1)
+	{
+		if (strcmp(argv[1], "--help") == 0 || strcmp(argv[1], "-?") == 0)
+		{
+			hlp(get_progname(argv[0]));
+			exit(0);
+		}
+		if (strcmp(argv[1], "--version") == 0 || strcmp(argv[1], "-V") == 0)
+		{
+			printf("%s (PostgreSQL) " PG_VERSION "\n", fixed_progname);
+			exit(0);
+		}
+	}
+}
+
+
+/*
+ * Make a database connection with the given parameters.
+ *
+ * An interactive password prompt is automatically issued if needed and
+ * allowed by cparams->prompt_password.
+ *
+ * If allow_password_reuse is true, we will try to re-use any password
+ * given during previous calls to this routine.  (Callers should not pass
+ * allow_password_reuse=true unless reconnecting to the same database+user
+ * as before, else we might create password exposure hazards.)
+ */
+PGconn *
+connectDatabase(const ConnParams *cparams, const char *progname,
+				bool echo, bool fail_ok, bool allow_password_reuse)
+{
+	PGconn	   *conn;
+	bool		new_pass;
+	static bool have_password = false;
+	static char password[100];
+
+	/* Callers must supply at least dbname; other params can be NULL */
+	Assert(cparams->dbname);
+
+	if (!allow_password_reuse)
+		have_password = false;
+
+	if (cparams->prompt_password == TRI_YES && !have_password)
+	{
+		simple_prompt("Password: ", password, sizeof(password), false);
+		have_password = true;
+	}
+
+	/*
+	 * Start the connection.  Loop until we have a password if requested by
+	 * backend.
+	 */
+	do
+	{
+		const char *keywords[8];
+		const char *values[8];
+		int			i = 0;
+
+		/*
+		 * If dbname is a connstring, its entries can override the other
+		 * values obtained from cparams; but in turn, override_dbname can
+		 * override the dbname component of it.
+		 */
+		keywords[i] = "host";
+		values[i++] = cparams->pghost;
+		keywords[i] = "port";
+		values[i++] = cparams->pgport;
+		keywords[i] = "user";
+		values[i++] = cparams->pguser;
+		keywords[i] = "password";
+		values[i++] = have_password ? password : NULL;
+		keywords[i] = "dbname";
+		values[i++] = cparams->dbname;
+		if (cparams->override_dbname)
+		{
+			keywords[i] = "dbname";
+			values[i++] = cparams->override_dbname;
+		}
+		keywords[i] = "fallback_application_name";
+		values[i++] = progname;
+		keywords[i] = NULL;
+		values[i++] = NULL;
+		Assert(i <= lengthof(keywords));
+
+		new_pass = false;
+		conn = PQconnectdbParams(keywords, values, true);
+
+		if (!conn)
+		{
+			pg_log_error("could not connect to database %s: out of memory",
+						 cparams->dbname);
+			exit(1);
+		}
+
+		/*
+		 * No luck?  Trying asking (again) for a password.
+		 */
+		if (PQstatus(conn) == CONNECTION_BAD &&
+			PQconnectionNeedsPassword(conn) &&
+			cparams->prompt_password != TRI_NO)
+		{
+			PQfinish(conn);
+			simple_prompt("Password: ", password, sizeof(password), false);
+			have_password = true;
+			new_pass = true;
+		}
+	} while (new_pass);
+
+	/* check to see that the backend connection was successfully made */
+	if (PQstatus(conn) == CONNECTION_BAD)
+	{
+		if (fail_ok)
+		{
+			PQfinish(conn);
+			return NULL;
+		}
+		pg_log_error("could not connect to database %s: %s",
+					 cparams->dbname, PQerrorMessage(conn));
+		exit(1);
+	}
+
+	/* Start strict; callers may override this. */
+	PQclear(executeQuery(conn, ALWAYS_SECURE_SEARCH_PATH_SQL, echo));
+
+	return conn;
+}
+
+/*
+ * Try to connect to the appropriate maintenance database.
+ *
+ * This differs from connectDatabase only in that it has a rule for
+ * inserting a default "dbname" if none was given (which is why cparams
+ * is not const).  Note that cparams->dbname should typically come from
+ * a --maintenance-db command line parameter.
+ */
+PGconn *
+connectMaintenanceDatabase(ConnParams *cparams,
+						   const char *progname, bool echo)
+{
+	PGconn	   *conn;
+
+	/* If a maintenance database name was specified, just connect to it. */
+	if (cparams->dbname)
+		return connectDatabase(cparams, progname, echo, false, false);
+
+	/* Otherwise, try postgres first and then template1. */
+	cparams->dbname = "postgres";
+	conn = connectDatabase(cparams, progname, echo, true, false);
+	if (!conn)
+	{
+		cparams->dbname = "template1";
+		conn = connectDatabase(cparams, progname, echo, false, false);
+	}
+	return conn;
+}
+
+/*
+ * Disconnect the given connection, canceling any statement if one is active.
+ */
+void
+disconnectDatabase(PGconn *conn)
+{
+	char		errbuf[256];
+
+	Assert(conn != NULL);
+
+	if (PQtransactionStatus(conn) == PQTRANS_ACTIVE)
+	{
+		PGcancel   *cancel;
+
+		if ((cancel = PQgetCancel(conn)))
+		{
+			(void) PQcancel(cancel, errbuf, sizeof(errbuf));
+			PQfreeCancel(cancel);
+		}
+	}
+
+	PQfinish(conn);
+}
+
+/*
+ * Run a query, return the results, exit program on failure.
+ */
+PGresult *
+executeQuery(PGconn *conn, const char *query, bool echo)
+{
+	PGresult   *res;
+
+	if (echo)
+		printf("%s\n", query);
+
+	res = PQexec(conn, query);
+	if (!res ||
+		PQresultStatus(res) != PGRES_TUPLES_OK)
+	{
+		pg_log_error("query failed: %s", PQerrorMessage(conn));
+		pg_log_info("query was: %s", query);
+		PQfinish(conn);
+		exit(1);
+	}
+
+	return res;
+}
+
+
+/*
+ * As above for a SQL command (which returns nothing).
+ */
+void
+executeCommand(PGconn *conn, const char *query, bool echo)
+{
+	PGresult   *res;
+
+	if (echo)
+		printf("%s\n", query);
+
+	res = PQexec(conn, query);
+	if (!res ||
+		PQresultStatus(res) != PGRES_COMMAND_OK)
+	{
+		pg_log_error("query failed: %s", PQerrorMessage(conn));
+		pg_log_info("query was: %s", query);
+		PQfinish(conn);
+		exit(1);
+	}
+
+	PQclear(res);
+}
+
+
+/*
+ * As above for a SQL maintenance command (returns command success).
+ * Command is executed with a cancel handler set, so Ctrl-C can
+ * interrupt it.
+ */
+bool
+executeMaintenanceCommand(PGconn *conn, const char *query, bool echo)
+{
+	PGresult   *res;
+	bool		r;
+
+	if (echo)
+		printf("%s\n", query);
+
+	SetCancelConn(conn);
+	res = PQexec(conn, query);
+	ResetCancelConn();
+
+	r = (res && PQresultStatus(res) == PGRES_COMMAND_OK);
+
+	if (res)
+		PQclear(res);
+
+	return r;
+}
+
+/*
+ * Consume all the results generated for the given connection until
+ * nothing remains.  If at least one error is encountered, return false.
+ * Note that this will block if the connection is busy.
+ */
+bool
+consumeQueryResult(PGconn *conn)
+{
+	bool		ok = true;
+	PGresult   *result;
+
+	SetCancelConn(conn);
+	while ((result = PQgetResult(conn)) != NULL)
+	{
+		if (!processQueryResult(conn, result))
+			ok = false;
+	}
+	ResetCancelConn();
+	return ok;
+}
+
+/*
+ * Process (and delete) a query result.  Returns true if there's no error,
+ * false otherwise -- but errors about trying to work on a missing relation
+ * are reported and subsequently ignored.
+ */
+bool
+processQueryResult(PGconn *conn, PGresult *result)
+{
+	/*
+	 * If it's an error, report it.  Errors about a missing table are harmless
+	 * so we continue processing; but die for other errors.
+	 */
+	if (PQresultStatus(result) != PGRES_COMMAND_OK)
+	{
+		char	   *sqlState = PQresultErrorField(result, PG_DIAG_SQLSTATE);
+
+		pg_log_error("processing of database \"%s\" failed: %s",
+					 PQdb(conn), PQerrorMessage(conn));
+
+		if (sqlState && strcmp(sqlState, ERRCODE_UNDEFINED_TABLE) != 0)
+		{
+			PQclear(result);
+			return false;
+		}
+	}
+
+	PQclear(result);
+	return true;
+}
+
+
+/*
+ * Split TABLE[(COLUMNS)] into TABLE and [(COLUMNS)] portions.  When you
+ * finish using them, pg_free(*table).  *columns is a pointer into "spec",
+ * possibly to its NUL terminator.
+ */
+void
+splitTableColumnsSpec(const char *spec, int encoding,
+					  char **table, const char **columns)
+{
+	bool		inquotes = false;
+	const char *cp = spec;
+
+	/*
+	 * Find the first '(' not identifier-quoted.  Based on
+	 * dequote_downcase_identifier().
+	 */
+	while (*cp && (*cp != '(' || inquotes))
+	{
+		if (*cp == '"')
+		{
+			if (inquotes && cp[1] == '"')
+				cp++;			/* pair does not affect quoting */
+			else
+				inquotes = !inquotes;
+			cp++;
+		}
+		else
+			cp += PQmblenBounded(cp, encoding);
+	}
+	*table = pnstrdup(spec, cp - spec);
+	*columns = cp;
+}
+
+/*
+ * Break apart TABLE[(COLUMNS)] of "spec".  With the reset_val of search_path
+ * in effect, have regclassin() interpret the TABLE portion.  Append to "buf"
+ * the qualified name of TABLE, followed by any (COLUMNS).  Exit on failure.
+ * We use this to interpret --table=foo under the search path psql would get,
+ * in advance of "ANALYZE public.foo" under the always-secure search path.
+ */
+void
+appendQualifiedRelation(PQExpBuffer buf, const char *spec,
+						PGconn *conn, bool echo)
+{
+	char	   *table;
+	const char *columns;
+	PQExpBufferData sql;
+	PGresult   *res;
+	int			ntups;
+
+	splitTableColumnsSpec(spec, PQclientEncoding(conn), &table, &columns);
+
+	/*
+	 * Query must remain ABSOLUTELY devoid of unqualified names.  This would
+	 * be unnecessary given a regclassin() variant taking a search_path
+	 * argument.
+	 */
+	initPQExpBuffer(&sql);
+	appendPQExpBufferStr(&sql,
+						 "SELECT c.relname, ns.nspname\n"
+						 " FROM pg_catalog.pg_class c,"
+						 " pg_catalog.pg_namespace ns\n"
+						 " WHERE c.relnamespace OPERATOR(pg_catalog.=) ns.oid\n"
+						 "  AND c.oid OPERATOR(pg_catalog.=) ");
+	appendStringLiteralConn(&sql, table, conn);
+	appendPQExpBufferStr(&sql, "::pg_catalog.regclass;");
+
+	executeCommand(conn, "RESET search_path;", echo);
+
+	/*
+	 * One row is a typical result, as is a nonexistent relation ERROR.
+	 * regclassin() unconditionally accepts all-digits input as an OID; if no
+	 * relation has that OID; this query returns no rows.  Catalog corruption
+	 * might elicit other row counts.
+	 */
+	res = executeQuery(conn, sql.data, echo);
+	ntups = PQntuples(res);
+	if (ntups != 1)
+	{
+		pg_log_error(ngettext("query returned %d row instead of one: %s",
+							  "query returned %d rows instead of one: %s",
+							  ntups),
+					 ntups, sql.data);
+		PQfinish(conn);
+		exit(1);
+	}
+	appendPQExpBufferStr(buf,
+						 fmtQualifiedId(PQgetvalue(res, 0, 1),
+										PQgetvalue(res, 0, 0)));
+	appendPQExpBufferStr(buf, columns);
+	PQclear(res);
+	termPQExpBuffer(&sql);
+	pg_free(table);
+
+	PQclear(executeQuery(conn, ALWAYS_SECURE_SEARCH_PATH_SQL, echo));
+}
+
+
+/*
+ * Check yes/no answer in a localized way.  1=yes, 0=no, -1=neither.
+ */
+
+/* translator: abbreviation for "yes" */
+#define PG_YESLETTER gettext_noop("y")
+/* translator: abbreviation for "no" */
+#define PG_NOLETTER gettext_noop("n")
+
+bool
+yesno_prompt(const char *question)
+{
+	char		prompt[256];
+
+	/*------
+	   translator: This is a question followed by the translated options for
+	   "yes" and "no". */
+	snprintf(prompt, sizeof(prompt), _("%s (%s/%s) "),
+			 _(question), _(PG_YESLETTER), _(PG_NOLETTER));
+
+	for (;;)
+	{
+		char		resp[10];
+
+		simple_prompt(prompt, resp, sizeof(resp), true);
+
+		if (strcmp(resp, _(PG_YESLETTER)) == 0)
+			return true;
+		if (strcmp(resp, _(PG_NOLETTER)) == 0)
+			return false;
+
+		printf(_("Please answer \"%s\" or \"%s\".\n"),
+			   _(PG_YESLETTER), _(PG_NOLETTER));
+	}
+}