postgresql/src/backend/archive/shell_archive.c

141 lines
3.7 KiB
C

/*-------------------------------------------------------------------------
*
* shell_archive.c
*
* This archiving function uses a user-specified shell command (the
* archive_command GUC) to copy write-ahead log files. It is used as the
* default, but other modules may define their own custom archiving logic.
*
* Copyright (c) 2022-2024, PostgreSQL Global Development Group
*
* IDENTIFICATION
* src/backend/archive/shell_archive.c
*
*-------------------------------------------------------------------------
*/
#include "postgres.h"
#include <sys/wait.h>
#include "access/xlog.h"
#include "archive/archive_module.h"
#include "archive/shell_archive.h"
#include "common/percentrepl.h"
#include "pgstat.h"
static bool shell_archive_configured(ArchiveModuleState *state);
static bool shell_archive_file(ArchiveModuleState *state,
const char *file,
const char *path);
static void shell_archive_shutdown(ArchiveModuleState *state);
static const ArchiveModuleCallbacks shell_archive_callbacks = {
.startup_cb = NULL,
.check_configured_cb = shell_archive_configured,
.archive_file_cb = shell_archive_file,
.shutdown_cb = shell_archive_shutdown
};
const ArchiveModuleCallbacks *
shell_archive_init(void)
{
return &shell_archive_callbacks;
}
static bool
shell_archive_configured(ArchiveModuleState *state)
{
if (XLogArchiveCommand[0] != '\0')
return true;
arch_module_check_errdetail("%s is not set.",
"archive_command");
return false;
}
static bool
shell_archive_file(ArchiveModuleState *state, const char *file,
const char *path)
{
char *xlogarchcmd;
char *nativePath = NULL;
int rc;
if (path)
{
nativePath = pstrdup(path);
make_native_path(nativePath);
}
xlogarchcmd = replace_percent_placeholders(XLogArchiveCommand,
"archive_command", "fp",
file, nativePath);
ereport(DEBUG3,
(errmsg_internal("executing archive command \"%s\"",
xlogarchcmd)));
fflush(NULL);
pgstat_report_wait_start(WAIT_EVENT_ARCHIVE_COMMAND);
rc = system(xlogarchcmd);
pgstat_report_wait_end();
if (rc != 0)
{
/*
* If either the shell itself, or a called command, died on a signal,
* abort the archiver. We do this because system() ignores SIGINT and
* SIGQUIT while waiting; so a signal is very likely something that
* should have interrupted us too. Also die if the shell got a hard
* "command not found" type of error. If we overreact it's no big
* deal, the postmaster will just start the archiver again.
*/
int lev = wait_result_is_any_signal(rc, true) ? FATAL : LOG;
if (WIFEXITED(rc))
{
ereport(lev,
(errmsg("archive command failed with exit code %d",
WEXITSTATUS(rc)),
errdetail("The failed archive command was: %s",
xlogarchcmd)));
}
else if (WIFSIGNALED(rc))
{
#if defined(WIN32)
ereport(lev,
(errmsg("archive command was terminated by exception 0x%X",
WTERMSIG(rc)),
errhint("See C include file \"ntstatus.h\" for a description of the hexadecimal value."),
errdetail("The failed archive command was: %s",
xlogarchcmd)));
#else
ereport(lev,
(errmsg("archive command was terminated by signal %d: %s",
WTERMSIG(rc), pg_strsignal(WTERMSIG(rc))),
errdetail("The failed archive command was: %s",
xlogarchcmd)));
#endif
}
else
{
ereport(lev,
(errmsg("archive command exited with unrecognized status %d",
rc),
errdetail("The failed archive command was: %s",
xlogarchcmd)));
}
return false;
}
elog(DEBUG1, "archived write-ahead log file \"%s\"", file);
return true;
}
static void
shell_archive_shutdown(ArchiveModuleState *state)
{
elog(DEBUG1, "archiver process shutting down");
}