Allow the delay in psql's \watch command to be a fractional second.

Instead of just "2" seconds, allow eg. "2.5" seconds.  Per request
from Alvaro Herrera.  No docs change since the docs didn't say you
couldn't do this already.

diff --git a/src/bin/psql/command.c b/src/bin/psql/command.c
index 6319b030c7a61d55eabf30d7c472b3a12154c2c0..3ea12b8f8f955f17c10ce64ed22eb51db2c72190 100644 (file)
--- a/src/bin/psql/command.c
+++ b/src/bin/psql/command.c
@@ -66,7 +66,7 @@ static bool do_edit(const char *filename_arg, PQExpBuffer query_buf,
                int lineno, bool *edited);
 static bool do_connect(char *dbname, char *user, char *host, char *port);
 static bool do_shell(const char *command);
-static bool do_watch(PQExpBuffer query_buf, long sleep);
+static bool do_watch(PQExpBuffer query_buf, double sleep);
 static bool lookup_object_oid(EditableObjectType obj_type, const char *desc,
                                  Oid *obj_oid);
 static bool get_create_object_cmd(EditableObjectType obj_type, Oid oid,
@@ -1577,12 +1577,12 @@ exec_command(const char *cmd,
        {
                char       *opt = psql_scan_slash_option(scan_state,
                                                                                                 OT_NORMAL, NULL, true);
-               long            sleep = 2;
+               double          sleep = 2;
 
                /* Convert optional sleep-length argument */
                if (opt)
                {
-                       sleep = strtol(opt, NULL, 10);
+                       sleep = strtod(opt, NULL);
                        if (sleep <= 0)
                                sleep = 1;
                        free(opt);
@@ -3017,8 +3017,9 @@ do_shell(const char *command)
  * onto a bunch of exec_command's variables to silence stupider compilers.
  */
 static bool
-do_watch(PQExpBuffer query_buf, long sleep)
+do_watch(PQExpBuffer query_buf, double sleep)
 {
+       long            sleep_ms = (long) (sleep * 1000);
        printQueryOpt myopt = pset.popt;
        const char *user_title;
        char       *title;
@@ -3064,10 +3065,10 @@ do_watch(PQExpBuffer query_buf, long sleep)
                        asctimebuf[i] = '\0';
 
                if (user_title)
-                       snprintf(title, title_len, _("%s\t%s (every %lds)\n"),
+                       snprintf(title, title_len, _("%s\t%s (every %gs)\n"),
                                         user_title, asctimebuf, sleep);
                else
-                       snprintf(title, title_len, _("%s (every %lds)\n"),
+                       snprintf(title, title_len, _("%s (every %gs)\n"),
                                         asctimebuf, sleep);
                myopt.title = title;
 
@@ -3091,15 +3092,19 @@ do_watch(PQExpBuffer query_buf, long sleep)
 
                /*
                 * Enable 'watch' cancellations and wait a while before running the
-                * query again.  Break the sleep into short intervals since pg_usleep
-                * isn't interruptible on some platforms.
+                * query again.  Break the sleep into short intervals (at most 1s)
+                * since pg_usleep isn't interruptible on some platforms.
                 */
                sigint_interrupt_enabled = true;
-               for (i = 0; i < sleep; i++)
+               i = sleep_ms;
+               while (i > 0)
                {
-                       pg_usleep(1000000L);
+                       long            s = Min(i, 1000L);
+
+                       pg_usleep(s * 1000L);
                        if (cancel_pressed)
                                break;
+                       i -= s;
                }
                sigint_interrupt_enabled = false;
        }