Adding upstream version 15.5.upstream/15.5

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

2 files changed, 463 insertions, 0 deletions

diff --git a/src/backend/main/Makefile b/src/backend/main/Makefile
new file mode 100644
index 0000000..6d34072
--- /dev/null
+++ b/src/backend/main/Makefile
@@ -0,0 +1,18 @@
+#-------------------------------------------------------------------------
+#
+# Makefile--
+#    Makefile for main
+#
+# IDENTIFICATION
+#    src/backend/main/Makefile
+#
+#-------------------------------------------------------------------------
+
+subdir = src/backend/main
+top_builddir = ../../..
+include $(top_builddir)/src/Makefile.global
+
+OBJS = \
+	main.o
+
+include $(top_srcdir)/src/backend/common.mk
diff --git a/src/backend/main/main.c b/src/backend/main/main.c
new file mode 100644
index 0000000..f8f7ebb
--- /dev/null
+++ b/src/backend/main/main.c
@@ -0,0 +1,445 @@
+/*-------------------------------------------------------------------------
+ *
+ * main.c
+ *	  Stub main() routine for the postgres executable.
+ *
+ * This does some essential startup tasks for any incarnation of postgres
+ * (postmaster, standalone backend, standalone bootstrap process, or a
+ * separately exec'd child of a postmaster) and then dispatches to the
+ * proper FooMain() routine for the incarnation.
+ *
+ *
+ * Portions Copyright (c) 1996-2022, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1994, Regents of the University of California
+ *
+ *
+ * IDENTIFICATION
+ *	  src/backend/main/main.c
+ *
+ *-------------------------------------------------------------------------
+ */
+#include "postgres.h"
+
+#include <unistd.h>
+
+#if defined(WIN32)
+#include <crtdbg.h>
+#endif
+
+#if defined(__NetBSD__)
+#include <sys/param.h>
+#endif
+
+#if defined(_M_AMD64) && _MSC_VER == 1800
+#include <math.h>
+#include <versionhelpers.h>
+#endif
+
+#include "bootstrap/bootstrap.h"
+#include "common/username.h"
+#include "port/atomics.h"
+#include "postmaster/postmaster.h"
+#include "storage/spin.h"
+#include "tcop/tcopprot.h"
+#include "utils/help_config.h"
+#include "utils/memutils.h"
+#include "utils/pg_locale.h"
+#include "utils/ps_status.h"
+
+
+const char *progname;
+
+
+static void startup_hacks(const char *progname);
+static void init_locale(const char *categoryname, int category, const char *locale);
+static void help(const char *progname);
+static void check_root(const char *progname);
+
+
+/*
+ * Any Postgres server process begins execution here.
+ */
+int
+main(int argc, char *argv[])
+{
+	bool		do_check_root = true;
+
+	/*
+	 * If supported on the current platform, set up a handler to be called if
+	 * the backend/postmaster crashes with a fatal signal or exception.
+	 */
+#if defined(WIN32) && defined(HAVE_MINIDUMP_TYPE)
+	pgwin32_install_crashdump_handler();
+#endif
+
+	progname = get_progname(argv[0]);
+
+	/*
+	 * Platform-specific startup hacks
+	 */
+	startup_hacks(progname);
+
+	/*
+	 * Remember the physical location of the initially given argv[] array for
+	 * possible use by ps display.  On some platforms, the argv[] storage must
+	 * be overwritten in order to set the process title for ps. In such cases
+	 * save_ps_display_args makes and returns a new copy of the argv[] array.
+	 *
+	 * save_ps_display_args may also move the environment strings to make
+	 * extra room. Therefore this should be done as early as possible during
+	 * startup, to avoid entanglements with code that might save a getenv()
+	 * result pointer.
+	 */
+	argv = save_ps_display_args(argc, argv);
+
+	/*
+	 * Fire up essential subsystems: error and memory management
+	 *
+	 * Code after this point is allowed to use elog/ereport, though
+	 * localization of messages may not work right away, and messages won't go
+	 * anywhere but stderr until GUC settings get loaded.
+	 */
+	MemoryContextInit();
+
+	/*
+	 * Set up locale information
+	 */
+	set_pglocale_pgservice(argv[0], PG_TEXTDOMAIN("postgres"));
+
+	/*
+	 * In the postmaster, absorb the environment values for LC_COLLATE and
+	 * LC_CTYPE.  Individual backends will change these later to settings
+	 * taken from pg_database, but the postmaster cannot do that.  If we leave
+	 * these set to "C" then message localization might not work well in the
+	 * postmaster.
+	 */
+	init_locale("LC_COLLATE", LC_COLLATE, "");
+	init_locale("LC_CTYPE", LC_CTYPE, "");
+
+	/*
+	 * LC_MESSAGES will get set later during GUC option processing, but we set
+	 * it here to allow startup error messages to be localized.
+	 */
+#ifdef LC_MESSAGES
+	init_locale("LC_MESSAGES", LC_MESSAGES, "");
+#endif
+
+	/*
+	 * We keep these set to "C" always, except transiently in pg_locale.c; see
+	 * that file for explanations.
+	 */
+	init_locale("LC_MONETARY", LC_MONETARY, "C");
+	init_locale("LC_NUMERIC", LC_NUMERIC, "C");
+	init_locale("LC_TIME", LC_TIME, "C");
+
+	/*
+	 * Now that we have absorbed as much as we wish to from the locale
+	 * environment, remove any LC_ALL setting, so that the environment
+	 * variables installed by pg_perm_setlocale have force.
+	 */
+	unsetenv("LC_ALL");
+
+	check_strxfrm_bug();
+
+	/*
+	 * Catch standard options before doing much else, in particular before we
+	 * insist on not being root.
+	 */
+	if (argc > 1)
+	{
+		if (strcmp(argv[1], "--help") == 0 || strcmp(argv[1], "-?") == 0)
+		{
+			help(progname);
+			exit(0);
+		}
+		if (strcmp(argv[1], "--version") == 0 || strcmp(argv[1], "-V") == 0)
+		{
+			fputs(PG_BACKEND_VERSIONSTR, stdout);
+			exit(0);
+		}
+
+		/*
+		 * In addition to the above, we allow "--describe-config" and "-C var"
+		 * to be called by root.  This is reasonably safe since these are
+		 * read-only activities.  The -C case is important because pg_ctl may
+		 * try to invoke it while still holding administrator privileges on
+		 * Windows.  Note that while -C can normally be in any argv position,
+		 * if you want to bypass the root check you must put it first.  This
+		 * reduces the risk that we might misinterpret some other mode's -C
+		 * switch as being the postmaster/postgres one.
+		 */
+		if (strcmp(argv[1], "--describe-config") == 0)
+			do_check_root = false;
+		else if (argc > 2 && strcmp(argv[1], "-C") == 0)
+			do_check_root = false;
+	}
+
+	/*
+	 * Make sure we are not running as root, unless it's safe for the selected
+	 * option.
+	 */
+	if (do_check_root)
+		check_root(progname);
+
+	/*
+	 * Dispatch to one of various subprograms depending on first argument.
+	 */
+
+	if (argc > 1 && strcmp(argv[1], "--check") == 0)
+		BootstrapModeMain(argc, argv, true);
+	else if (argc > 1 && strcmp(argv[1], "--boot") == 0)
+		BootstrapModeMain(argc, argv, false);
+#ifdef EXEC_BACKEND
+	else if (argc > 1 && strncmp(argv[1], "--fork", 6) == 0)
+		SubPostmasterMain(argc, argv);
+#endif
+	else if (argc > 1 && strcmp(argv[1], "--describe-config") == 0)
+		GucInfoMain();
+	else if (argc > 1 && strcmp(argv[1], "--single") == 0)
+		PostgresSingleUserMain(argc, argv,
+							   strdup(get_user_name_or_exit(progname)));
+	else
+		PostmasterMain(argc, argv);
+	/* the functions above should not return */
+	abort();
+}
+
+
+
+/*
+ * Place platform-specific startup hacks here.  This is the right
+ * place to put code that must be executed early in the launch of any new
+ * server process.  Note that this code will NOT be executed when a backend
+ * or sub-bootstrap process is forked, unless we are in a fork/exec
+ * environment (ie EXEC_BACKEND is defined).
+ *
+ * XXX The need for code here is proof that the platform in question
+ * is too brain-dead to provide a standard C execution environment
+ * without help.  Avoid adding more here, if you can.
+ */
+static void
+startup_hacks(const char *progname)
+{
+	/*
+	 * Windows-specific execution environment hacking.
+	 */
+#ifdef WIN32
+	{
+		WSADATA		wsaData;
+		int			err;
+
+		/* Make output streams unbuffered by default */
+		setvbuf(stdout, NULL, _IONBF, 0);
+		setvbuf(stderr, NULL, _IONBF, 0);
+
+		/* Prepare Winsock */
+		err = WSAStartup(MAKEWORD(2, 2), &wsaData);
+		if (err != 0)
+		{
+			write_stderr("%s: WSAStartup failed: %d\n",
+						 progname, err);
+			exit(1);
+		}
+
+		/*
+		 * By default abort() only generates a crash-dump in *non* debug
+		 * builds. As our Assert() / ExceptionalCondition() uses abort(),
+		 * leaving the default in place would make debugging harder.
+		 *
+		 * MINGW's own C runtime doesn't have _set_abort_behavior(). When
+		 * targeting Microsoft's UCRT with mingw, it never links to the debug
+		 * version of the library and thus doesn't need the call to
+		 * _set_abort_behavior() either.
+		 */
+#if !defined(__MINGW32__) && !defined(__MINGW64__)
+		_set_abort_behavior(_CALL_REPORTFAULT | _WRITE_ABORT_MSG,
+							_CALL_REPORTFAULT | _WRITE_ABORT_MSG);
+#endif							/* !defined(__MINGW32__) &&
+								 * !defined(__MINGW64__) */
+
+		/*
+		 * SEM_FAILCRITICALERRORS causes more errors to be reported to
+		 * callers.
+		 *
+		 * We used to also specify SEM_NOGPFAULTERRORBOX, but that prevents
+		 * windows crash reporting from working. Which includes registered
+		 * just-in-time debuggers, making it unnecessarily hard to debug
+		 * problems on windows. Now we try to disable sources of popups
+		 * separately below (note that SEM_NOGPFAULTERRORBOX did not actually
+		 * prevent all sources of such popups).
+		 */
+		SetErrorMode(SEM_FAILCRITICALERRORS);
+
+		/*
+		 * Show errors on stderr instead of popup box (note this doesn't
+		 * affect errors originating in the C runtime, see below).
+		 */
+		_set_error_mode(_OUT_TO_STDERR);
+
+		/*
+		 * In DEBUG builds, errors, including assertions, C runtime errors are
+		 * reported via _CrtDbgReport. By default such errors are displayed
+		 * with a popup (even with NOGPFAULTERRORBOX), preventing forward
+		 * progress. Instead report such errors stderr (and the debugger).
+		 * This is C runtime specific and thus the above incantations aren't
+		 * sufficient to suppress these popups.
+		 */
+		_CrtSetReportMode(_CRT_ERROR, _CRTDBG_MODE_FILE | _CRTDBG_MODE_DEBUG);
+		_CrtSetReportFile(_CRT_ERROR, _CRTDBG_FILE_STDERR);
+		_CrtSetReportMode(_CRT_ASSERT, _CRTDBG_MODE_FILE | _CRTDBG_MODE_DEBUG);
+		_CrtSetReportFile(_CRT_ASSERT, _CRTDBG_FILE_STDERR);
+		_CrtSetReportMode(_CRT_WARN, _CRTDBG_MODE_FILE | _CRTDBG_MODE_DEBUG);
+		_CrtSetReportFile(_CRT_WARN, _CRTDBG_FILE_STDERR);
+
+#if defined(_M_AMD64) && _MSC_VER == 1800
+
+		/*----------
+		 * Avoid crashing in certain floating-point operations if we were
+		 * compiled for x64 with MS Visual Studio 2013 and are running on
+		 * Windows prior to 7/2008R2 SP1 on an AVX2-capable CPU.
+		 *
+		 * Ref: https://connect.microsoft.com/VisualStudio/feedback/details/811093/visual-studio-2013-rtm-c-x64-code-generation-bug-for-avx2-instructions
+		 *----------
+		 */
+		if (!IsWindows7SP1OrGreater())
+		{
+			_set_FMA3_enable(0);
+		}
+#endif							/* defined(_M_AMD64) && _MSC_VER == 1800 */
+
+	}
+#endif							/* WIN32 */
+
+	/*
+	 * Initialize dummy_spinlock, in case we are on a platform where we have
+	 * to use the fallback implementation of pg_memory_barrier().
+	 */
+	SpinLockInit(&dummy_spinlock);
+}
+
+
+/*
+ * Make the initial permanent setting for a locale category.  If that fails,
+ * perhaps due to LC_foo=invalid in the environment, use locale C.  If even
+ * that fails, perhaps due to out-of-memory, the entire startup fails with it.
+ * When this returns, we are guaranteed to have a setting for the given
+ * category's environment variable.
+ */
+static void
+init_locale(const char *categoryname, int category, const char *locale)
+{
+	if (pg_perm_setlocale(category, locale) == NULL &&
+		pg_perm_setlocale(category, "C") == NULL)
+		elog(FATAL, "could not adopt \"%s\" locale nor C locale for %s",
+			 locale, categoryname);
+}
+
+
+
+/*
+ * Help display should match the options accepted by PostmasterMain()
+ * and PostgresMain().
+ *
+ * XXX On Windows, non-ASCII localizations of these messages only display
+ * correctly if the console output code page covers the necessary characters.
+ * Messages emitted in write_console() do not exhibit this problem.
+ */
+static void
+help(const char *progname)
+{
+	printf(_("%s is the PostgreSQL server.\n\n"), progname);
+	printf(_("Usage:\n  %s [OPTION]...\n\n"), progname);
+	printf(_("Options:\n"));
+	printf(_("  -B NBUFFERS        number of shared buffers\n"));
+	printf(_("  -c NAME=VALUE      set run-time parameter\n"));
+	printf(_("  -C NAME            print value of run-time parameter, then exit\n"));
+	printf(_("  -d 1-5             debugging level\n"));
+	printf(_("  -D DATADIR         database directory\n"));
+	printf(_("  -e                 use European date input format (DMY)\n"));
+	printf(_("  -F                 turn fsync off\n"));
+	printf(_("  -h HOSTNAME        host name or IP address to listen on\n"));
+	printf(_("  -i                 enable TCP/IP connections\n"));
+	printf(_("  -k DIRECTORY       Unix-domain socket location\n"));
+#ifdef USE_SSL
+	printf(_("  -l                 enable SSL connections\n"));
+#endif
+	printf(_("  -N MAX-CONNECT     maximum number of allowed connections\n"));
+	printf(_("  -p PORT            port number to listen on\n"));
+	printf(_("  -s                 show statistics after each query\n"));
+	printf(_("  -S WORK-MEM        set amount of memory for sorts (in kB)\n"));
+	printf(_("  -V, --version      output version information, then exit\n"));
+	printf(_("  --NAME=VALUE       set run-time parameter\n"));
+	printf(_("  --describe-config  describe configuration parameters, then exit\n"));
+	printf(_("  -?, --help         show this help, then exit\n"));
+
+	printf(_("\nDeveloper options:\n"));
+	printf(_("  -f s|i|o|b|t|n|m|h forbid use of some plan types\n"));
+	printf(_("  -n                 do not reinitialize shared memory after abnormal exit\n"));
+	printf(_("  -O                 allow system table structure changes\n"));
+	printf(_("  -P                 disable system indexes\n"));
+	printf(_("  -t pa|pl|ex        show timings after each query\n"));
+	printf(_("  -T                 send SIGSTOP to all backend processes if one dies\n"));
+	printf(_("  -W NUM             wait NUM seconds to allow attach from a debugger\n"));
+
+	printf(_("\nOptions for single-user mode:\n"));
+	printf(_("  --single           selects single-user mode (must be first argument)\n"));
+	printf(_("  DBNAME             database name (defaults to user name)\n"));
+	printf(_("  -d 0-5             override debugging level\n"));
+	printf(_("  -E                 echo statement before execution\n"));
+	printf(_("  -j                 do not use newline as interactive query delimiter\n"));
+	printf(_("  -r FILENAME        send stdout and stderr to given file\n"));
+
+	printf(_("\nOptions for bootstrapping mode:\n"));
+	printf(_("  --boot             selects bootstrapping mode (must be first argument)\n"));
+	printf(_("  --check            selects check mode (must be first argument)\n"));
+	printf(_("  DBNAME             database name (mandatory argument in bootstrapping mode)\n"));
+	printf(_("  -r FILENAME        send stdout and stderr to given file\n"));
+
+	printf(_("\nPlease read the documentation for the complete list of run-time\n"
+			 "configuration settings and how to set them on the command line or in\n"
+			 "the configuration file.\n\n"
+			 "Report bugs to <%s>.\n"), PACKAGE_BUGREPORT);
+	printf(_("%s home page: <%s>\n"), PACKAGE_NAME, PACKAGE_URL);
+}
+
+
+
+static void
+check_root(const char *progname)
+{
+#ifndef WIN32
+	if (geteuid() == 0)
+	{
+		write_stderr("\"root\" execution of the PostgreSQL server is not permitted.\n"
+					 "The server must be started under an unprivileged user ID to prevent\n"
+					 "possible system security compromise.  See the documentation for\n"
+					 "more information on how to properly start the server.\n");
+		exit(1);
+	}
+
+	/*
+	 * Also make sure that real and effective uids are the same. Executing as
+	 * a setuid program from a root shell is a security hole, since on many
+	 * platforms a nefarious subroutine could setuid back to root if real uid
+	 * is root.  (Since nobody actually uses postgres as a setuid program,
+	 * trying to actively fix this situation seems more trouble than it's
+	 * worth; we'll just expend the effort to check for it.)
+	 */
+	if (getuid() != geteuid())
+	{
+		write_stderr("%s: real and effective user IDs must match\n",
+					 progname);
+		exit(1);
+	}
+#else							/* WIN32 */
+	if (pgwin32_is_admin())
+	{
+		write_stderr("Execution of PostgreSQL by a user with administrative permissions is not\n"
+					 "permitted.\n"
+					 "The server must be started under an unprivileged user ID to prevent\n"
+					 "possible system security compromises.  See the documentation for\n"
+					 "more information on how to properly start the server.\n");
+		exit(1);
+	}
+#endif							/* WIN32 */
+}