At Tue, 24 Oct 2023 07:37:22 +0000, "Hayato Kuroda (Fujitsu)"
<kuroda.hay...@fujitsu.com> wrote in
> Dear Horiguchi-san,
>
> Thanks for updates! I was quite not sure the Windows env, but I can post
> comments.
> (We need reviews by windows-friendly developers...)
Indeed, I haven't managed to successfully build using Meson on
Windows...
> Formatting of messages for write_stderr() seem different from others. In v3,
> I slightly modified for readability like below. I wanted to let you know just
> in case
> because you did not say anything about these changes...
Ah. Sorry, I was lazy about the messages because I didn't regard this
to be at that stage yet.
In the attached, fixed the existing two messages, and adjusted one
message to display an error code, all in the consistent format.
Thanks!
--
Kyotaro Horiguchi
NTT Open Source Software Center
>From 65013b5ccebd101f91be0e46b5209dc9cfcc7d5f Mon Sep 17 00:00:00 2001
From: Kyotaro Horiguchi <horikyota....@gmail.com>
Date: Tue, 24 Oct 2023 11:43:57 +0900
Subject: [PATCH v5 1/3] Disable autoruns for cmd.exe on Windows
On Windows, we use cmd.exe to launch the postmaster process for easy
redirection setup. However, cmd.exe may execute other programs at
startup due to autorun configurations. This patch adds /D flag to the
launcher cmd.exe command line to disable autorun settings written in
the registry.
---
src/bin/pg_ctl/pg_ctl.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/src/bin/pg_ctl/pg_ctl.c b/src/bin/pg_ctl/pg_ctl.c
index 807d7023a9..3ac2fcc004 100644
--- a/src/bin/pg_ctl/pg_ctl.c
+++ b/src/bin/pg_ctl/pg_ctl.c
@@ -553,11 +553,11 @@ start_postmaster(void)
else
close(fd);
- cmd = psprintf("\"%s\" /C \"\"%s\" %s%s < \"%s\" >> \"%s\" 2>&1\"",
+ cmd = psprintf("\"%s\" /D /C \"\"%s\" %s%s < \"%s\" >> \"%s\" 2>&1\"",
comspec, exec_path, pgdata_opt, post_opts, DEVNULL, log_file);
}
else
- cmd = psprintf("\"%s\" /C \"\"%s\" %s%s < \"%s\" 2>&1\"",
+ cmd = psprintf("\"%s\" /D /C \"\"%s\" %s%s < \"%s\" 2>&1\"",
comspec, exec_path, pgdata_opt, post_opts, DEVNULL);
if (!CreateRestrictedProcess(cmd, &pi, false))
--
2.39.3
>From 18c9a319b5160721d08cc1d3a3df770a63756f65 Mon Sep 17 00:00:00 2001
From: Kyotaro Horiguchi <horikyota....@gmail.com>
Date: Tue, 24 Oct 2023 14:46:50 +0900
Subject: [PATCH v5 2/3] Improve pg_ctl postmaster process check on Windows
Currently pg_ctl on Windows does not verify that it actually executed
a postmaster process due to lack of process ID knowledge. This can
lead to false positives in cases where another pg_ctl instance starts
a different server simultaneously.
This patch adds the capability to identify the process ID of the
launched postmaster on Windows, similar to other OS versions, ensuring
more reliable detection of concurrent server startups.
---
src/bin/pg_ctl/pg_ctl.c | 102 ++++++++++++++++++++++++++++++++++++----
1 file changed, 93 insertions(+), 9 deletions(-)
diff --git a/src/bin/pg_ctl/pg_ctl.c b/src/bin/pg_ctl/pg_ctl.c
index 3ac2fcc004..221049db0e 100644
--- a/src/bin/pg_ctl/pg_ctl.c
+++ b/src/bin/pg_ctl/pg_ctl.c
@@ -132,6 +132,7 @@ static void adjust_data_dir(void);
#ifdef WIN32
#include <versionhelpers.h>
+#include <tlhelp32.h>
static bool pgwin32_IsInstalled(SC_HANDLE);
static char *pgwin32_CommandLine(bool);
static void pgwin32_doRegister(void);
@@ -142,6 +143,7 @@ static void WINAPI pgwin32_ServiceMain(DWORD, LPTSTR *);
static void pgwin32_doRunAsService(void);
static int CreateRestrictedProcess(char *cmd, PROCESS_INFORMATION *processInfo, bool as_service);
static PTOKEN_PRIVILEGES GetPrivilegesToDelete(HANDLE hToken);
+static pid_t pgwin32_find_postmaster_pid(pid_t shell_pid);
#endif
static pid_t get_pgpid(bool is_status_request);
@@ -609,7 +611,11 @@ wait_for_postmaster_start(pid_t pm_pid, bool do_checkpoint)
/* File is complete enough for us, parse it */
pid_t pmpid;
time_t pmstart;
-
+#ifndef WIN32
+ pid_t wait_pid = pm_pid;
+#else
+ pid_t wait_pid = pgwin32_find_postmaster_pid(pm_pid);
+#endif
/*
* Make sanity checks. If it's for the wrong PID, or the recorded
* start time is before pg_ctl started, then either we are looking
@@ -619,14 +625,8 @@ wait_for_postmaster_start(pid_t pm_pid, bool do_checkpoint)
*/
pmpid = atol(optlines[LOCK_FILE_LINE_PID - 1]);
pmstart = atol(optlines[LOCK_FILE_LINE_START_TIME - 1]);
- if (pmstart >= start_time - 2 &&
-#ifndef WIN32
- pmpid == pm_pid
-#else
- /* Windows can only reject standalone-backend PIDs */
- pmpid > 0
-#endif
- )
+
+ if (pmstart >= start_time - 2 && pmpid == wait_pid)
{
/*
* OK, seems to be a valid pidfile from our child. Check the
@@ -1950,6 +1950,90 @@ GetPrivilegesToDelete(HANDLE hToken)
return tokenPrivs;
}
+
+/*
+ * Find the PID of the launched postmaster.
+ *
+ * On Windows, the cmd.exe doesn't support the exec command. As a result, we
+ * don't directly get the postmaster's PID. This function identifies the PID of
+ * the postmaster started by the child cmd.exe.
+ *
+ * Returns the postmaster's PID. If the shell is alive but the postmaster is
+ * missing, returns 0. Otherwise terminates this command with an error.
+ *
+ * This function uses PID 0 as an invalid value, assuming the system idle
+ * process occupies it and it won't be a PID for a shell or postmaster.
+ */
+static pid_t
+pgwin32_find_postmaster_pid(pid_t shell_pid)
+{
+ HANDLE hSnapshot;
+ PROCESSENTRY32 ppe;
+ pid_t pm_pid = 0; /* abusing 0 as an invalid value */
+ bool multiple_children = false;
+ DWORD last_error;
+
+ /* create a process snapshot */
+ hSnapshot = CreateToolhelp32Snapshot(TH32CS_SNAPPROCESS, 0);
+ if (hSnapshot == INVALID_HANDLE_VALUE)
+ {
+ write_stderr(_("%s: CreateToolhelp32Snapshot failed: error code %lu\n"),
+ progname, (unsigned long) GetLastError());
+ exit(1);
+ }
+
+ /* start iterating on the snapshot */
+ ppe.dwSize = sizeof(PROCESSENTRY32);
+ if (!Process32First(hSnapshot, &ppe))
+ {
+ write_stderr(_("%s: Process32First failed: error code %lu\n"),
+ progname, (unsigned long) GetLastError());
+ exit(1);
+ }
+
+ /*
+ * Iterate over the snapshot
+ *
+ * Check for duplicate processes to ensure reliability.
+ *
+ * The launcher shell might start other cmd.exe instances or programs
+ * besides postgres.exe. Veryfying the program file name is essential.
+ *
+ * The launcher shell process isn't checked in this function. It will be
+ * checked by the caller.
+ */
+ do
+ {
+ if (ppe.th32ParentProcessID == shell_pid &&
+ strcmp("postgres.exe", ppe.szExeFile) == 0)
+ {
+ if (pm_pid != ppe.th32ProcessID && pm_pid != 0)
+ multiple_children = true;
+ pm_pid = ppe.th32ProcessID;
+ }
+ }
+ while (Process32Next(hSnapshot, &ppe));
+
+ /* avoid multiple calls primary for clarity, not out of necessity */
+ last_error = GetLastError();
+ if (last_error != ERROR_NO_MORE_FILES)
+ {
+ write_stderr(_("%s: Process32Next failed: error code %lu\n"),
+ progname, (unsigned long) last_error);
+ exit(1);
+ }
+ CloseHandle(hSnapshot);
+
+ /* assuming the launching shell executes a single process */
+ if (multiple_children)
+ {
+ write_stderr(_("%s: multiple postmasters found\n"),
+ progname);
+ exit(1);
+ }
+
+ return pm_pid;
+}
#endif /* WIN32 */
static void
--
2.39.3
>From 5ee4384af0edef313452ebd8babd628ddbb64dc9 Mon Sep 17 00:00:00 2001
From: Kyotaro Horiguchi <horikyota....@gmail.com>
Date: Tue, 24 Oct 2023 14:47:24 +0900
Subject: [PATCH v5 3/3] Remove short sleep from 001_start_stop.pl
Previous commits ensures reliable detection whether the postmaster has really
started or not, so the short sleep in a test is not needed anymore. It was
originally introduced by 6bcce258.
---
src/bin/pg_ctl/t/001_start_stop.pl | 5 -----
1 file changed, 5 deletions(-)
diff --git a/src/bin/pg_ctl/t/001_start_stop.pl b/src/bin/pg_ctl/t/001_start_stop.pl
index f019fe1703..590a82338f 100644
--- a/src/bin/pg_ctl/t/001_start_stop.pl
+++ b/src/bin/pg_ctl/t/001_start_stop.pl
@@ -46,11 +46,6 @@ my $ctlcmd = [
];
command_like($ctlcmd, qr/done.*server started/s, 'pg_ctl start');
-# sleep here is because Windows builds can't check postmaster.pid exactly,
-# so they may mistake a pre-existing postmaster.pid for one created by the
-# postmaster they start. Waiting more than the 2 seconds slop time allowed
-# by wait_for_postmaster() prevents that mistake.
-sleep 3 if ($windows_os);
command_fails([ 'pg_ctl', 'start', '-D', "$tempdir/data" ],
'second pg_ctl start fails');
command_ok([ 'pg_ctl', 'stop', '-D', "$tempdir/data" ], 'pg_ctl stop');
--
2.39.3
