Use carriage returns for data insertion logs in pgbench on terminal

This is similar to what pg_basebackup and pg_rewind do when reporting
cumulative data, and that's more user-friendly.  Carriage returns are
now used when stderr points to a terminal, and newlines are used in
other cases, like a redirection to a log file.

Author: Amit Langote
Reviewed-by: Fabien Coelho
Discussion: https://postgr.es/m/CA+HiwqFNwEjPeVaQsp2L7DyCPv1Eg1guwhrVhzMYqUJUk8ULKg@mail.gmail.com

diff --git a/src/bin/pgbench/pgbench.c b/src/bin/pgbench/pgbench.c
index 5129aea51603fe241288abe624084cb487c8d275..6ab79eef99fba6db4791a791e1d68302d186cfaf 100644 (file)
--- a/src/bin/pgbench/pgbench.c
+++ b/src/bin/pgbench/pgbench.c
@@ -3835,6 +3835,9 @@ initGenerateDataClientSide(PGconn *con)
                                remaining_sec;
        int                     log_interval = 1;
 
+       /* Stay on the same line if reporting to a terminal */
+       char            eol = isatty(fileno(stderr)) ? '\r' : '\n';
+
        fprintf(stderr, "generating data (client-side)...\n");
 
        /*
@@ -3910,10 +3913,10 @@ initGenerateDataClientSide(PGconn *con)
                        elapsed_sec = INSTR_TIME_GET_DOUBLE(diff);
                        remaining_sec = ((double) scale * naccounts - j) * elapsed_sec / j;
 
-                       fprintf(stderr, INT64_FORMAT " of " INT64_FORMAT " tuples (%d%%) done (elapsed %.2f s, remaining %.2f s)\n",
+                       fprintf(stderr, INT64_FORMAT " of " INT64_FORMAT " tuples (%d%%) done (elapsed %.2f s, remaining %.2f s)%c",
                                        j, (int64) naccounts * scale,
                                        (int) (((int64) j * 100) / (naccounts * (int64) scale)),
-                                       elapsed_sec, remaining_sec);
+                                       elapsed_sec, remaining_sec, eol);
                }
                /* let's not call the timing for each row, but only each 100 rows */
                else if (use_quiet && (j % 100 == 0))
@@ -3927,16 +3930,19 @@ initGenerateDataClientSide(PGconn *con)
                        /* have we reached the next interval (or end)? */
                        if ((j == scale * naccounts) || (elapsed_sec >= log_interval * LOG_STEP_SECONDS))
                        {
-                               fprintf(stderr, INT64_FORMAT " of " INT64_FORMAT " tuples (%d%%) done (elapsed %.2f s, remaining %.2f s)\n",
+                               fprintf(stderr, INT64_FORMAT " of " INT64_FORMAT " tuples (%d%%) done (elapsed %.2f s, remaining %.2f s)%c",
                                                j, (int64) naccounts * scale,
-                                               (int) (((int64) j * 100) / (naccounts * (int64) scale)), elapsed_sec, remaining_sec);
+                                               (int) (((int64) j * 100) / (naccounts * (int64) scale)), elapsed_sec, remaining_sec, eol);
 
                                /* skip to the next interval */
                                log_interval = (int) ceil(elapsed_sec / LOG_STEP_SECONDS);
                        }
                }
-
        }
+
+       if (eol != '\n')
+               fputc('\n', stderr);    /* Need to move to next line */
+
        if (PQputline(con, "\\.\n"))
        {
                fprintf(stderr, "very last PQputline failed\n");