Fix pg_resetxlog to use correct path to postmaster.pid.

Since we've already chdir'd into the data directory, the file should
be referenced as just "postmaster.pid", without prefixing the directory
path.  This is harmless in the normal case where an absolute PGDATA path
is used, but quite dangerous if a relative path is specified, since the
program might then fail to notice an active postmaster.

Reported by Hari Babu.  This got broken in my commit
eb5949d190e80360386113fde0f05854f0c9824d, so patch all active versions.

diff --git a/src/bin/pg_resetxlog/pg_resetxlog.c b/src/bin/pg_resetxlog/pg_resetxlog.c
index 5ecf5c49304692abc3702b1089586a803f2b20f4..80e826897c7a8b5ab8ee7ab5d4175f38fe8ce8d3 100644 (file)
--- a/src/bin/pg_resetxlog/pg_resetxlog.c
+++ b/src/bin/pg_resetxlog/pg_resetxlog.c
@@ -95,7 +95,6 @@ main(int argc, char *argv[])
    char       *endptr3;
    char       *DataDir;
    int         fd;
-   char        path[MAXPGPATH];
 
    set_pglocale_pgservice(argv[0], PG_TEXTDOMAIN("pg_resetxlog"));
 
@@ -270,13 +269,12 @@ main(int argc, char *argv[])
     * Check for a postmaster lock file --- if there is one, refuse to
     * proceed, on grounds we might be interfering with a live installation.
     */
-   snprintf(path, MAXPGPATH, "%s/postmaster.pid", DataDir);
-
-   if ((fd = open(path, O_RDONLY, 0)) < 0)
+   if ((fd = open("postmaster.pid", O_RDONLY, 0)) < 0)
    {
        if (errno != ENOENT)
        {
-           fprintf(stderr, _("%s: could not open file \"%s\" for reading: %s\n"), progname, path, strerror(errno));
+           fprintf(stderr, _("%s: could not open file \"%s\" for reading: %s\n"),
+                   progname, "postmaster.pid", strerror(errno));
            exit(1);
        }
    }
@@ -284,7 +282,7 @@ main(int argc, char *argv[])
    {
        fprintf(stderr, _("%s: lock file \"%s\" exists\n"
                          "Is a server running?  If not, delete the lock file and try again.\n"),
-               progname, path);
+               progname, "postmaster.pid");
        exit(1);
    }