* miscinit.c
* miscellaneous initialization support stuff
*
- * Portions Copyright (c) 1996-2010, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1996-2015, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
*
#include <sys/param.h>
#include <signal.h>
+#include <time.h>
#include <sys/file.h>
#include <sys/stat.h>
#include <sys/time.h>
+#include <sys/types.h>
#include <fcntl.h>
#include <unistd.h>
#include <grp.h>
#include <utime.h>
#endif
+#include "access/htup_details.h"
#include "catalog/pg_authid.h"
#include "mb/pg_wchar.h"
#include "miscadmin.h"
#include "postmaster/postmaster.h"
#include "storage/fd.h"
#include "storage/ipc.h"
+#include "storage/latch.h"
#include "storage/pg_shmem.h"
#include "storage/proc.h"
#include "storage/procarray.h"
ProcessingMode Mode = InitProcessing;
-/* Note: we rely on this to initialize as zeroes */
-static char socketLockFile[MAXPGPATH];
+/* List of lock files to be removed at proc exit */
+static List *lock_files = NIL;
+static Latch LocalLatchData;
/* ----------------------------------------------------------------
* ignoring system indexes support stuff
*
* NOTE: "ignoring system indexes" means we do not use the system indexes
* for lookups (either in hardwired catalog accesses or in planner-generated
- * plans). We do, however, still update the indexes when a catalog
+ * plans). We do, however, still update the indexes when a catalog
* modification is made.
* ----------------------------------------------------------------
*/
DataDir)));
}
-/*
- * If the given pathname isn't already absolute, make it so, interpreting
- * it relative to the current working directory.
- *
- * Also canonicalizes the path. The result is always a malloc'd copy.
- *
- * Note: interpretation of relative-path arguments during postmaster startup
- * should happen before doing ChangeToDataDir(), else the user will probably
- * not like the results.
- */
-char *
-make_absolute_path(const char *path)
-{
- char *new;
-
- /* Returning null for null input is convenient for some callers */
- if (path == NULL)
- return NULL;
-
- if (!is_absolute_path(path))
- {
- char *buf;
- size_t buflen;
-
- buflen = MAXPGPATH;
- for (;;)
- {
- buf = malloc(buflen);
- if (!buf)
- ereport(FATAL,
- (errcode(ERRCODE_OUT_OF_MEMORY),
- errmsg("out of memory")));
-
- if (getcwd(buf, buflen))
- break;
- else if (errno == ERANGE)
- {
- free(buf);
- buflen *= 2;
- continue;
- }
- else
- {
- free(buf);
- elog(FATAL, "could not get current working directory: %m");
- }
- }
-
- new = malloc(strlen(buf) + strlen(path) + 2);
- if (!new)
- ereport(FATAL,
- (errcode(ERRCODE_OUT_OF_MEMORY),
- errmsg("out of memory")));
- sprintf(new, "%s/%s", buf, path);
- free(buf);
- }
- else
- {
- new = strdup(path);
- if (!new)
- ereport(FATAL,
- (errcode(ERRCODE_OUT_OF_MEMORY),
- errmsg("out of memory")));
- }
-
- /* Make sure punctuation is canonical, too */
- canonicalize_path(new);
-
- return new;
-}
-
/* ----------------------------------------------------------------
* User ID state
/* We also remember if a SET ROLE is currently active */
static bool SetRoleIsActive = false;
+/*
+ * Initialize the basic environment for a postmaster child
+ *
+ * Should be called as early as possible after the child's startup.
+ */
+void
+InitPostmasterChild(void)
+{
+ IsUnderPostmaster = true; /* we are a postmaster subprocess now */
+
+ MyProcPid = getpid(); /* reset MyProcPid */
+
+ MyStartTime = time(NULL); /* set our start time in case we call elog */
+
+ /*
+ * make sure stderr is in binary mode before anything can possibly be
+ * written to it, in case it's actually the syslogger pipe, so the pipe
+ * chunking protocol isn't disturbed. Non-logpipe data gets translated on
+ * redirection (e.g. via pg_ctl -l) anyway.
+ */
+#ifdef WIN32
+ _setmode(fileno(stderr), _O_BINARY);
+#endif
+
+ /* We don't want the postmaster's proc_exit() handlers */
+ on_exit_reset();
+
+ /* Initialize process-local latch support */
+ InitializeLatchSupport();
+ MyLatch = &LocalLatchData;
+ InitLatch(MyLatch);
+
+ /*
+ * If possible, make this process a group leader, so that the postmaster
+ * can signal any child processes too. Not all processes will have
+ * children, but for consistency we make all postmaster child processes do
+ * this.
+ */
+#ifdef HAVE_SETSID
+ if (setsid() < 0)
+ elog(FATAL, "setsid() failed: %m");
+#endif
+}
+
+/*
+ * Initialize the basic environment for a standalone process.
+ *
+ * argv0 has to be suitable to find the program's executable.
+ */
+void
+InitStandaloneProcess(const char *argv0)
+{
+ Assert(!IsPostmasterEnvironment);
+
+ MyProcPid = getpid(); /* reset MyProcPid */
+
+ MyStartTime = time(NULL); /* set our start time in case we call elog */
+
+ /* Initialize process-local latch support */
+ InitializeLatchSupport();
+ MyLatch = &LocalLatchData;
+ InitLatch(MyLatch);
+
+ /* Compute paths, no postmaster to inherit from */
+ if (my_exec_path[0] == '\0')
+ {
+ if (find_my_exec(argv0, my_exec_path) < 0)
+ elog(FATAL, "%s: could not locate my own executable path",
+ argv0);
+ }
+
+ if (pkglib_path[0] == '\0')
+ get_pkglib_path(my_exec_path, pkglib_path);
+}
+
+void
+SwitchToSharedLatch(void)
+{
+ Assert(MyLatch == &LocalLatchData);
+ Assert(MyProc != NULL);
+
+ MyLatch = &MyProc->procLatch;
+
+ /*
+ * Set the shared latch as the local one might have been set. This
+ * shouldn't normally be necessary as code is supposed to check the
+ * condition before waiting for the latch, but a bit care can't hurt.
+ */
+ SetLatch(MyLatch);
+}
+
+void
+SwitchBackToLocalLatch(void)
+{
+ Assert(MyLatch != &LocalLatchData);
+ Assert(MyProc != NULL && MyLatch == &MyProc->procLatch);
+
+ MyLatch = &LocalLatchData;
+ SetLatch(MyLatch);
+}
/*
* GetUserId - get the current effective user ID.
CurrentUserId = userid;
}
+/*
+ * GetAuthenticatedUserId - get the authenticated user ID
+ */
+Oid
+GetAuthenticatedUserId(void)
+{
+ AssertState(OidIsValid(AuthenticatedUserId));
+ return AuthenticatedUserId;
+}
+
/*
* GetUserIdAndSecContext/SetUserIdAndSecContext - get/set the current user ID
* and the SecurityRestrictionContext flags.
*
- * Currently there are two valid bits in SecurityRestrictionContext:
+ * Currently there are three valid bits in SecurityRestrictionContext:
*
* SECURITY_LOCAL_USERID_CHANGE indicates that we are inside an operation
- * that is temporarily changing CurrentUserId via these functions. This is
+ * that is temporarily changing CurrentUserId via these functions. This is
* needed to indicate that the actual value of CurrentUserId is not in sync
* with guc.c's internal state, so SET ROLE has to be disallowed.
*
* where the called functions are really supposed to be side-effect-free
* anyway, such as VACUUM/ANALYZE/REINDEX.
*
+ * SECURITY_NOFORCE_RLS indicates that we are inside an operation which should
+ * ignore the FORCE ROW LEVEL SECURITY per-table indication. This is used to
+ * ensure that FORCE RLS does not mistakenly break referential integrity
+ * checks. Note that this is intentionally only checked when running as the
+ * owner of the table (which should always be the case for referential
+ * integrity checks).
+ *
* Unlike GetUserId, GetUserIdAndSecContext does *not* Assert that the current
* value of CurrentUserId is valid; nor does SetUserIdAndSecContext require
* the new value to be valid. In fact, these routines had better not
* ever throw any kind of error. This is because they are used by
* StartTransaction and AbortTransaction to save/restore the settings,
* and during the first transaction within a backend, the value to be saved
- * and perhaps restored is indeed invalid. We have to be able to get
+ * and perhaps restored is indeed invalid. We have to be able to get
* through AbortTransaction without asserting in case InitPostgres fails.
*/
void
return (SecurityRestrictionContext & SECURITY_RESTRICTED_OPERATION) != 0;
}
+/*
+ * InNoForceRLSOperation - are we ignoring FORCE ROW LEVEL SECURITY ?
+ */
+bool
+InNoForceRLSOperation(void)
+{
+ return (SecurityRestrictionContext & SECURITY_NOFORCE_RLS) != 0;
+}
+
/*
* These are obsolete versions of Get/SetUserIdAndSecContext that are
* only provided for bug-compatibility with some rather dubious code in
- * pljava. We allow the userid to be set, but only when not inside a
+ * pljava. We allow the userid to be set, but only when not inside a
* security restriction context.
*/
void
}
+/*
+ * Check whether specified role has explicit REPLICATION privilege
+ */
+bool
+has_rolreplication(Oid roleid)
+{
+ bool result = false;
+ HeapTuple utup;
+
+ utup = SearchSysCache1(AUTHOID, ObjectIdGetDatum(roleid));
+ if (HeapTupleIsValid(utup))
+ {
+ result = ((Form_pg_authid) GETSTRUCT(utup))->rolreplication;
+ ReleaseSysCache(utup);
+ }
+ return result;
+}
+
/*
* Initialize user identity during normal backend startup
*/
void
-InitializeSessionUserId(const char *rolename)
+InitializeSessionUserId(const char *rolename, Oid roleid)
{
HeapTuple roleTup;
Form_pg_authid rform;
- Oid roleid;
/*
* Don't do scans if we're bootstrapping, none of the system catalogs
/* call only once */
AssertState(!OidIsValid(AuthenticatedUserId));
- roleTup = SearchSysCache1(AUTHNAME, PointerGetDatum(rolename));
+ if (rolename != NULL)
+ roleTup = SearchSysCache1(AUTHNAME, PointerGetDatum(rolename));
+ else
+ roleTup = SearchSysCache1(AUTHOID, ObjectIdGetDatum(roleid));
if (!HeapTupleIsValid(roleTup))
ereport(FATAL,
(errcode(ERRCODE_INVALID_AUTHORIZATION_SPECIFICATION),
* Check connection limit for this role.
*
* There is a race condition here --- we create our PGPROC before
- * checking for other PGPROCs. If two backends did this at about the
+ * checking for other PGPROCs. If two backends did this at about the
* same time, they might both think they were over the limit, while
* ideally one should succeed and one fail. Getting that to work
* exactly seems more trouble than it is worth, however; instead we
InitializeSessionUserIdStandalone(void)
{
/*
- * This function should only be called in single-user mode and in
- * autovacuum workers.
+ * This function should only be called in single-user mode, in autovacuum
+ * workers, and in background workers.
*/
- AssertState(!IsUnderPostmaster || IsAutoVacuumWorkerProcess());
+ AssertState(!IsUnderPostmaster || IsAutoVacuumWorkerProcess() || IsBackgroundWorker);
/* call only once */
AssertState(!OidIsValid(AuthenticatedUserId));
* Change Role ID while running (SET ROLE)
*
* If roleid is InvalidOid, we are doing SET ROLE NONE: revert to the
- * session user authorization. In this case the is_superuser argument
+ * session user authorization. In this case the is_superuser argument
* is ignored.
*
* When roleid is not InvalidOid, the caller must have checked whether
/*
- * Get user name from user oid
+ * Get user name from user oid, returns NULL for nonexistent roleid if noerr
+ * is true.
*/
char *
-GetUserNameFromId(Oid roleid)
+GetUserNameFromId(Oid roleid, bool noerr)
{
HeapTuple tuple;
char *result;
tuple = SearchSysCache1(AUTHOID, ObjectIdGetDatum(roleid));
if (!HeapTupleIsValid(tuple))
- ereport(ERROR,
- (errcode(ERRCODE_UNDEFINED_OBJECT),
- errmsg("invalid role OID: %u", roleid)));
-
- result = pstrdup(NameStr(((Form_pg_authid) GETSTRUCT(tuple))->rolname));
-
- ReleaseSysCache(tuple);
+ {
+ if (!noerr)
+ ereport(ERROR,
+ (errcode(ERRCODE_UNDEFINED_OBJECT),
+ errmsg("invalid role OID: %u", roleid)));
+ result = NULL;
+ }
+ else
+ {
+ result = pstrdup(NameStr(((Form_pg_authid) GETSTRUCT(tuple))->rolname));
+ ReleaseSysCache(tuple);
+ }
return result;
}
* Interlock-file support
*
* These routines are used to create both a data-directory lockfile
- * ($DATADIR/postmaster.pid) and a Unix-socket-file lockfile ($SOCKFILE.lock).
- * Both kinds of files contain the same info:
- *
- * Owning process' PID
- * Data directory path
- *
- * By convention, the owning process' PID is negated if it is a standalone
- * backend rather than a postmaster. This is just for informational purposes.
- * The path is also just for informational purposes (so that a socket lockfile
- * can be more easily traced to the associated postmaster).
- *
- * A data-directory lockfile can optionally contain a third line, containing
- * the key and ID for the shared memory block used by this postmaster.
+ * ($DATADIR/postmaster.pid) and Unix-socket-file lockfiles ($SOCKFILE.lock).
+ * Both kinds of files contain the same info initially, although we can add
+ * more information to a data-directory lockfile after it's created, using
+ * AddToDataDirLockFile(). See miscadmin.h for documentation of the contents
+ * of these lockfiles.
*
* On successful lockfile creation, a proc_exit callback to remove the
* lockfile is automatically created.
*/
/*
- * proc_exit callback to remove a lockfile.
+ * proc_exit callback to remove lockfiles.
*/
static void
-UnlinkLockFile(int status, Datum filename)
+UnlinkLockFiles(int status, Datum arg)
{
- char *fname = (char *) DatumGetPointer(filename);
+ ListCell *l;
- if (fname != NULL)
+ foreach(l, lock_files)
{
- if (unlink(fname) != 0)
- {
- /* Should we complain if the unlink fails? */
- }
- free(fname);
+ char *curfile = (char *) lfirst(l);
+
+ unlink(curfile);
+ /* Should we complain if the unlink fails? */
}
+ /* Since we're about to exit, no need to reclaim storage */
+ lock_files = NIL;
}
/*
* Create a lockfile.
*
- * filename is the name of the lockfile to create.
+ * filename is the path name of the lockfile to create.
* amPostmaster is used to determine how to encode the output PID.
+ * socketDir is the Unix socket directory path to include (possibly empty).
* isDDLock and refName are used to determine what error message to produce.
*/
static void
CreateLockFile(const char *filename, bool amPostmaster,
+ const char *socketDir,
bool isDDLock, const char *refName)
{
int fd;
my_gp_pid = 0;
/*
- * We need a loop here because of race conditions. But don't loop forever
+ * We need a loop here because of race conditions. But don't loop forever
* (for example, a non-writable $PGDATA directory might cause a failure
* that won't go away). 100 tries seems like plenty.
*/
/*
* Try to create the lock file --- O_EXCL makes this atomic.
*
- * Think not to make the file protection weaker than 0600. See
+ * Think not to make the file protection weaker than 0600. See
* comments below.
*/
fd = open(filename, O_RDWR | O_CREAT | O_EXCL, 0600);
filename)));
close(fd);
+ if (len == 0)
+ {
+ ereport(FATAL,
+ (errcode(ERRCODE_LOCK_FILE_EXISTS),
+ errmsg("lock file \"%s\" is empty", filename),
+ errhint("Either another server is starting, or the lock file is the remnant of a previous server startup crash.")));
+ }
+
buffer[len] = '\0';
encoded_pid = atoi(buffer);
* implies that the existing process has a different userid than we
* do, which means it cannot be a competing postmaster. A postmaster
* cannot successfully attach to a data directory owned by a userid
- * other than its own. (This is now checked directly in
+ * other than its own. (This is now checked directly in
* checkDataDir(), but has been true for a long time because of the
* restriction that the data directory isn't group- or
* world-accessible.) Also, since we create the lockfiles mode 600,
}
/*
- * No, the creating process did not exist. However, it could be that
+ * No, the creating process did not exist. However, it could be that
* the postmaster crashed (or more likely was kill -9'd by a clueless
- * admin) but has left orphan backends behind. Check for this by
+ * admin) but has left orphan backends behind. Check for this by
* looking to see if there is an associated shmem segment that is
* still in use.
*
- * Note: because postmaster.pid is written in two steps, we might not
- * find the shmem ID values in it; we can't treat that as an error.
+ * Note: because postmaster.pid is written in multiple steps, we might
+ * not find the shmem ID values in it; we can't treat that as an
+ * error.
*/
if (isDDLock)
{
- char *ptr = NULL;
+ char *ptr = buffer;
unsigned long id1,
id2;
- int lineno;
+ int lineno;
- for (lineno = 1; lineno <= 4; lineno++)
+ for (lineno = 1; lineno < LOCK_FILE_LINE_SHMEM_KEY; lineno++)
{
if ((ptr = strchr(ptr, '\n')) == NULL)
- {
- elog(LOG, "bogus data in \"%s\"", DIRECTORY_LOCK_FILE);
break;
- }
ptr++;
}
- if (ptr && sscanf(ptr, "%lu %lu", &id1, &id2) == 2)
+ if (ptr != NULL &&
+ sscanf(ptr, "%lu %lu", &id1, &id2) == 2)
{
if (PGSharedMemoryIsInUse(id1, id2))
ereport(FATAL,
"(key %lu, ID %lu) is still in use",
id1, id2),
errhint("If you're sure there are no old "
- "server processes still running, remove "
+ "server processes still running, remove "
"the shared memory block "
"or just delete the file \"%s\".",
filename)));
/*
* Looks like nobody's home. Unlink the file and try again to create
- * it. Need a loop because of possible race condition against other
+ * it. Need a loop because of possible race condition against other
* would-be creators.
*/
if (unlink(filename) < 0)
}
/*
- * Successfully created the file, now fill it.
+ * Successfully created the file, now fill it. See comment in miscadmin.h
+ * about the contents. Note that we write the same first five lines into
+ * both datadir and socket lockfiles; although more stuff may get added to
+ * the datadir lockfile later.
*/
- snprintf(buffer, sizeof(buffer), "%d\n%s\n%d\n%s\n",
+ snprintf(buffer, sizeof(buffer), "%d\n%s\n%ld\n%d\n%s\n",
amPostmaster ? (int) my_pid : -((int) my_pid),
- DataDir, PostPortNumber, UnixSocketDir);
+ DataDir,
+ (long) MyStartTime,
+ PostPortNumber,
+ socketDir);
+
+ /*
+ * In a standalone backend, the next line (LOCK_FILE_LINE_LISTEN_ADDR)
+ * will never receive data, so fill it in as empty now.
+ */
+ if (isDDLock && !amPostmaster)
+ strlcat(buffer, "\n", sizeof(buffer));
+
errno = 0;
if (write(fd, buffer, strlen(buffer)) != strlen(buffer))
{
}
/*
- * Arrange for automatic removal of lockfile at proc_exit.
+ * Arrange to unlink the lock file(s) at proc_exit. If this is the first
+ * one, set up the on_proc_exit function to do it; then add this lock file
+ * to the list of files to unlink.
+ */
+ if (lock_files == NIL)
+ on_proc_exit(UnlinkLockFiles, 0);
+
+ /*
+ * Use lcons so that the lock files are unlinked in reverse order of
+ * creation; this is critical!
*/
- on_proc_exit(UnlinkLockFile, PointerGetDatum(strdup(filename)));
+ lock_files = lcons(pstrdup(filename), lock_files);
}
/*
* When this is called, we must have already switched the working
* directory to DataDir, so we can just use a relative path. This
* helps ensure that we are locking the directory we should be.
+ *
+ * Note that the socket directory path line is initially written as empty.
+ * postmaster.c will rewrite it upon creating the first Unix socket.
*/
void
CreateDataDirLockFile(bool amPostmaster)
{
- CreateLockFile(DIRECTORY_LOCK_FILE, amPostmaster, true, DataDir);
+ CreateLockFile(DIRECTORY_LOCK_FILE, amPostmaster, "", true, DataDir);
}
/*
* Create a lockfile for the specified Unix socket file.
*/
void
-CreateSocketLockFile(const char *socketfile, bool amPostmaster)
+CreateSocketLockFile(const char *socketfile, bool amPostmaster,
+ const char *socketDir)
{
char lockfile[MAXPGPATH];
snprintf(lockfile, sizeof(lockfile), "%s.lock", socketfile);
- CreateLockFile(lockfile, amPostmaster, false, socketfile);
- /* Save name of lockfile for TouchSocketLockFile */
- strcpy(socketLockFile, lockfile);
+ CreateLockFile(lockfile, amPostmaster, socketDir, false, socketfile);
}
/*
- * TouchSocketLockFile -- mark socket lock file as recently accessed
+ * TouchSocketLockFiles -- mark socket lock files as recently accessed
*
- * This routine should be called every so often to ensure that the lock file
- * has a recent mod or access date. That saves it
+ * This routine should be called every so often to ensure that the socket
+ * lock files have a recent mod or access date. That saves them
* from being removed by overenthusiastic /tmp-directory-cleaner daemons.
* (Another reason we should never have put the socket file in /tmp...)
*/
void
-TouchSocketLockFile(void)
+TouchSocketLockFiles(void)
{
- /* Do nothing if we did not create a socket... */
- if (socketLockFile[0] != '\0')
+ ListCell *l;
+
+ foreach(l, lock_files)
{
+ char *socketLockFile = (char *) lfirst(l);
+
+ /* No need to touch the data directory lock file, we trust */
+ if (strcmp(socketLockFile, DIRECTORY_LOCK_FILE) == 0)
+ continue;
+
/*
* utime() is POSIX standard, utimes() is a common alternative; if we
* have neither, fall back to actually reading the file (which only
}
}
+
/*
- * Append information about a shared memory segment to the data directory
- * lock file.
+ * Add (or replace) a line in the data directory lock file.
+ * The given string should not include a trailing newline.
*
- * This may be called multiple times in the life of a postmaster, if we
- * delete and recreate shmem due to backend crash. Therefore, be prepared
- * to overwrite existing information. (As of 7.1, a postmaster only creates
- * one shm seg at a time; but for the purposes here, if we did have more than
- * one then any one of them would do anyway.)
+ * Note: because we don't truncate the file, if we were to rewrite a line
+ * with less data than it had before, there would be garbage after the last
+ * line. We don't ever actually do that, so not worth adding another kernel
+ * call to cover the possibility.
*/
void
-RecordSharedMemoryInLockFile(unsigned long id1, unsigned long id2)
+AddToDataDirLockFile(int target_line, const char *str)
{
int fd;
int len;
int lineno;
- char *ptr;
- char buffer[MAXPGPATH * 2 + 256];
+ char *srcptr;
+ char *destptr;
+ char srcbuffer[BLCKSZ];
+ char destbuffer[BLCKSZ];
fd = open(DIRECTORY_LOCK_FILE, O_RDWR | PG_BINARY, 0);
if (fd < 0)
DIRECTORY_LOCK_FILE)));
return;
}
- len = read(fd, buffer, sizeof(buffer) - 100);
+ len = read(fd, srcbuffer, sizeof(srcbuffer) - 1);
if (len < 0)
{
ereport(LOG,
close(fd);
return;
}
- buffer[len] = '\0';
+ srcbuffer[len] = '\0';
/*
- * Skip over first four lines (PID, pgdata, portnum, socketdir).
+ * Advance over lines we are not supposed to rewrite, then copy them to
+ * destbuffer.
*/
- ptr = buffer;
- for (lineno = 1; lineno <= 4; lineno++)
+ srcptr = srcbuffer;
+ for (lineno = 1; lineno < target_line; lineno++)
{
- if ((ptr = strchr(ptr, '\n')) == NULL)
+ if ((srcptr = strchr(srcptr, '\n')) == NULL)
{
- elog(LOG, "bogus data in \"%s\"", DIRECTORY_LOCK_FILE);
+ elog(LOG, "incomplete data in \"%s\": found only %d newlines while trying to add line %d",
+ DIRECTORY_LOCK_FILE, lineno - 1, target_line);
close(fd);
return;
}
- ptr++;
+ srcptr++;
}
-
+ memcpy(destbuffer, srcbuffer, srcptr - srcbuffer);
+ destptr = destbuffer + (srcptr - srcbuffer);
+
/*
- * Append key information. Format to try to keep it the same length
- * always (trailing junk won't hurt, but might confuse humans).
+ * Write or rewrite the target line.
*/
- sprintf(ptr, "%9lu %9lu\n", id1, id2);
+ snprintf(destptr, destbuffer + sizeof(destbuffer) - destptr, "%s\n", str);
+ destptr += strlen(destptr);
+
+ /*
+ * If there are more lines in the old file, append them to destbuffer.
+ */
+ if ((srcptr = strchr(srcptr, '\n')) != NULL)
+ {
+ srcptr++;
+ snprintf(destptr, destbuffer + sizeof(destbuffer) - destptr, "%s",
+ srcptr);
+ }
/*
* And rewrite the data. Since we write in a single kernel call, this
* update should appear atomic to onlookers.
*/
- len = strlen(buffer);
+ len = strlen(destbuffer);
errno = 0;
if (lseek(fd, (off_t) 0, SEEK_SET) != 0 ||
- (int) write(fd, buffer, len) != len)
+ (int) write(fd, destbuffer, len) != len)
{
/* if write didn't set errno, assume problem is no disk space */
if (errno == 0)
}
+/*
+ * Recheck that the data directory lock file still exists with expected
+ * content. Return TRUE if the lock file appears OK, FALSE if it isn't.
+ *
+ * We call this periodically in the postmaster. The idea is that if the
+ * lock file has been removed or replaced by another postmaster, we should
+ * do a panic database shutdown. Therefore, we should return TRUE if there
+ * is any doubt: we do not want to cause a panic shutdown unnecessarily.
+ * Transient failures like EINTR or ENFILE should not cause us to fail.
+ * (If there really is something wrong, we'll detect it on a future recheck.)
+ */
+bool
+RecheckDataDirLockFile(void)
+{
+ int fd;
+ int len;
+ long file_pid;
+ char buffer[BLCKSZ];
+
+ fd = open(DIRECTORY_LOCK_FILE, O_RDWR | PG_BINARY, 0);
+ if (fd < 0)
+ {
+ /*
+ * There are many foreseeable false-positive error conditions. For
+ * safety, fail only on enumerated clearly-something-is-wrong
+ * conditions.
+ */
+ switch (errno)
+ {
+ case ENOENT:
+ case ENOTDIR:
+ /* disaster */
+ ereport(LOG,
+ (errcode_for_file_access(),
+ errmsg("could not open file \"%s\": %m",
+ DIRECTORY_LOCK_FILE)));
+ return false;
+ default:
+ /* non-fatal, at least for now */
+ ereport(LOG,
+ (errcode_for_file_access(),
+ errmsg("could not open file \"%s\": %m; continuing anyway",
+ DIRECTORY_LOCK_FILE)));
+ return true;
+ }
+ }
+ len = read(fd, buffer, sizeof(buffer) - 1);
+ if (len < 0)
+ {
+ ereport(LOG,
+ (errcode_for_file_access(),
+ errmsg("could not read from file \"%s\": %m",
+ DIRECTORY_LOCK_FILE)));
+ close(fd);
+ return true; /* treat read failure as nonfatal */
+ }
+ buffer[len] = '\0';
+ close(fd);
+ file_pid = atol(buffer);
+ if (file_pid == getpid())
+ return true; /* all is well */
+
+ /* Trouble: someone's overwritten the lock file */
+ ereport(LOG,
+ (errmsg("lock file \"%s\" contains wrong PID: %ld instead of %ld",
+ DIRECTORY_LOCK_FILE, file_pid, (long) getpid())));
+ return false;
+}
+
+
/*-------------------------------------------------------------------------
* Version checking support
*-------------------------------------------------------------------------
* GUC variables: lists of library names to be preloaded at postmaster
* start and at backend start
*/
+char *session_preload_libraries_string = NULL;
char *shared_preload_libraries_string = NULL;
char *local_preload_libraries_string = NULL;
{
char *rawstring;
List *elemlist;
- int elevel;
ListCell *l;
if (libraries == NULL || libraries[0] == '\0')
return;
}
- /*
- * Choose notice level: avoid repeat messages when re-loading a library
- * that was preloaded into the postmaster. (Only possible in EXEC_BACKEND
- * configurations)
- */
-#ifdef EXEC_BACKEND
- if (IsUnderPostmaster && process_shared_preload_libraries_in_progress)
- elevel = DEBUG2;
- else
-#endif
- elevel = LOG;
-
foreach(l, elemlist)
{
char *tok = (char *) lfirst(l);
{
char *expanded;
- expanded = palloc(strlen("$libdir/plugins/") + strlen(filename) + 1);
- strcpy(expanded, "$libdir/plugins/");
- strcat(expanded, filename);
+ expanded = psprintf("$libdir/plugins/%s", filename);
pfree(filename);
filename = expanded;
}
load_file(filename, restricted);
- ereport(elevel,
+ ereport(DEBUG1,
(errmsg("loaded library \"%s\"", filename)));
pfree(filename);
}
* process any libraries that should be preloaded at backend start
*/
void
-process_local_preload_libraries(void)
+process_session_preload_libraries(void)
{
+ load_libraries(session_preload_libraries_string,
+ "session_preload_libraries",
+ false);
load_libraries(local_preload_libraries_string,
"local_preload_libraries",
true);