Improve error reporting when location specified by postgres -D does not exist

Previously, the first error seen would be that postgresql.conf does not
exist.  But for the case where the whole directory does not exist, give
an error message about that, together with a hint for how to create one.

diff --git a/src/backend/utils/misc/guc.c b/src/backend/utils/misc/guc.c
index 38ba82fe4b66fab912f1cf2a6226fb1726d54911..b8d34b59f58552f7721cbda087f475e204027d2a 100644 (file)
--- a/src/backend/utils/misc/guc.c
+++ b/src/backend/utils/misc/guc.c
@@ -4463,6 +4463,17 @@ SelectConfigFiles(const char *userDoption, const char *progname)
        else
                configdir = make_absolute_path(getenv("PGDATA"));
 
+       if (configdir && stat(configdir, &stat_buf) != 0)
+       {
+               write_stderr("%s: could not access \"%s\": %s\n",
+                                        progname,
+                                        configdir,
+                                        strerror(errno));
+               if (errno == ENOENT)
+                       write_stderr("Run initdb or pg_basebackup to initialize a PostgreSQL data directory.\n");
+               return false;
+       }
+
        /*
         * Find the configuration file: if config_file was specified on the
         * command line, use it, else use configdir/postgresql.conf.  In any case
@@ -4498,7 +4509,7 @@ SelectConfigFiles(const char *userDoption, const char *progname)
         */
        if (stat(ConfigFileName, &stat_buf) != 0)
        {
-               write_stderr("%s cannot access the server configuration file \"%s\": %s\n",
+               write_stderr("%s: could not access the server configuration file \"%s\": %s\n",
                                         progname, ConfigFileName, strerror(errno));
                free(configdir);
                return false;