- class="parameter">host or
- class="parameter">port are omitted or specified
- as -, the value of that parameter from the
- previous connection is used. If there is no previous
- connection, the
libpq default for
- the parameter's value is used.
+ server. The connection parameters to use can be specified either
+ using a positional syntax, or using conninfo> connection
+ strings as detailed in .
+ When using positional parameters, if any of
+ dbname,
+ username,
+ host or
+ port are omitted or
+ specified as -, the value of that parameter from
+ the previous connection is used; if there is no previous connection,
+ the
libpq default for the parameter's value
+ is used. When using conninfo> strings, no values from the
+ previous connection are used for the new connection.
+
+
+ If the new connection is successfully made, the previous
+ connection is closed.
If the connection attempt failed (wrong user name, access
denied, etc.), the previous connection will only be kept if
psql is in interactive mode. When
mechanism that scripts are not accidentally acting on the
wrong database on the other hand.
+
+ Examples:
+
+=> \c mydb myuser host.dom 6432
+=> \c service=foo
+=> \c "host=localhost port=5432 dbname=mydb connect_timeout=10 sslmode=disable"
+=> \c postgresql://tom@localhost/mydb?application_name=myapp
+
PGconn *o_conn = pset.db,
*n_conn;
char *password = NULL;
+ bool keep_password;
+ bool has_connection_string;
if (!o_conn && (!dbname || !user || !host || !port))
{
return false;
}
- if (!dbname)
- dbname = PQdb(o_conn);
+ /* grab values from the old connection, unless supplied by caller */
if (!user)
user = PQuser(o_conn);
if (!host)
if (!port)
port = PQport(o_conn);
+ has_connection_string =
+ dbname ? recognized_connection_string(dbname) : false;
+
+ /*
+ * Any change in the parameters read above makes us discard the password.
+ * We also discard it if we're to use a conninfo rather than the positional
+ * syntax.
+ */
+ keep_password =
+ ((strcmp(user, PQuser(o_conn)) == 0) &&
+ (!host || strcmp(host, PQhost(o_conn)) == 0) &&
+ (strcmp(port, PQport(o_conn)) == 0) &&
+ !has_connection_string);
+
+ /*
+ * Grab dbname from old connection unless supplied by caller. No password
+ * discard if this changes: passwords aren't (usually) database-specific.
+ */
+ if (!dbname)
+ dbname = PQdb(o_conn);
+
/*
* If the user asked to be prompted for a password, ask for one now. If
* not, use the password from the old connection, provided the username
{
password = prompt_for_password(user);
}
- else if (o_conn && user && strcmp(PQuser(o_conn), user) == 0)
+ else if (o_conn && keep_password)
{
- password = pg_strdup(PQpass(o_conn));
+ password = PQpass(o_conn);
+ if (password && *password)
+ password = pg_strdup(password);
+ else
+ password = NULL;
}
while (true)
#define PARAMS_ARRAY_SIZE 8
const char **keywords = pg_malloc(PARAMS_ARRAY_SIZE * sizeof(*keywords));
const char **values = pg_malloc(PARAMS_ARRAY_SIZE * sizeof(*values));
+ int paramnum = 0;
+
+ keywords[0] = "dbname";
+ values[0] = dbname;
+
+ if (!has_connection_string)
+ {
+ keywords[++paramnum] = "host";
+ values[paramnum] = host;
+ keywords[++paramnum] = "port";
+ values[paramnum] = port;
+ keywords[++paramnum] = "user";
+ values[paramnum] = user;
+ }
+ keywords[++paramnum] = "password";
+ values[paramnum] = password;
+ keywords[++paramnum] = "fallback_application_name";
+ values[paramnum] = pset.progname;
+ keywords[++paramnum] = "client_encoding";
+ values[paramnum] = (pset.notty || getenv("PGCLIENTENCODING")) ? NULL : "auto";
- keywords[0] = "host";
- values[0] = host;
- keywords[1] = "port";
- values[1] = port;
- keywords[2] = "user";
- values[2] = user;
- keywords[3] = "password";
- values[3] = password;
- keywords[4] = "dbname";
- values[4] = dbname;
- keywords[5] = "fallback_application_name";
- values[5] = pset.progname;
- keywords[6] = "client_encoding";
- values[6] = (pset.notty || getenv("PGCLIENTENCODING")) ? NULL : "auto";
- keywords[7] = NULL;
- values[7] = NULL;
+ /* add array terminator */
+ keywords[++paramnum] = NULL;
+ values[paramnum] = NULL;
n_conn = PQconnectdbParams(keywords, values, true);
- free(keywords);
- free(values);
+ pg_free(keywords);
+ pg_free(values);
/* We can immediately discard the password -- no longer needed */
if (password)
- free(password);
+ pg_free(password);
if (PQstatus(n_conn) == CONNECTION_OK)
break;
return;
}
+
+/*
+ * 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;
+}
fprintf(output, _("Connection\n"));
if (currdb)
- fprintf(output, _(" \\c[onnect] [DBNAME|- USER|- HOST|- PORT|-]\n"
+ fprintf(output, _(" \\c[onnect] {[DBNAME|- USER|- HOST|- PORT|-] | conninfo}\n"
" connect to new database (currently \"%s\")\n"),
currdb);
else
- fprintf(output, _(" \\c[onnect] [DBNAME|- USER|- HOST|- PORT|-]\n"
+ fprintf(output, _(" \\c[onnect] {[DBNAME|- USER|- HOST|- PORT|-] | conninfo}\n"
" connect to new database (currently no connection)\n"));
fprintf(output, _(" \\encoding [ENCODING] show or set client encoding\n"));
fprintf(output, _(" \\password [USERNAME] securely change the password for a user\n"));