Add thread.c for libpq threading, and hook it into libpq/configure.

configure

@@ -2824,7 +2824,11 @@ if test "${with_threads+set}" = set; then
 
   case $withval in
     yes)
-      :
+
+cat >>confdefs.h <<\_ACEOF
+#define USE_THREADS 1
+_ACEOF
+
       ;;
     no)
       :
@@ -2841,6 +2845,7 @@ else
 
 fi;
 
+
 echo "$as_me:$LINENO: result: $with_threads" >&5
 echo "${ECHO_T}$with_threads" >&6
 
@@ -3899,9 +3904,12 @@ case $host_os in
 			# these require no special flags or libraries
 			;;
 		freebsd2*|freebsd3*|freebsd4*) THREAD_CFLAGS="-pthread" ;;
-		freebsd*) THREAD_LIBS="-lc_r" ;;
+		freebsd*)
-		linux*) THREAD_LIBS="-lpthread"
+			THREAD_LIBS="-lc_r"
-			THREAD_CFLAGS="-D_REENTRANT" ;;
+			;;
+		linux*) THREAD_CFLAGS="-D_REENTRANT -D_THREAD_SAFE -D_POSIX_PTHREAD_SEMANTICS"
+			THREAD_LIBS="-lpthread"
+			;;
 		*)
 			# other operating systems might fail because they have pthread.h but need
 			# special libs we don't know about yet.
@@ -12818,6 +12826,97 @@ _ACEOF
 fi
 
 
+#
+# Check for re-entrant versions of certain functions
+#
+# Include special flags if required
+#
+_CFLAGS="$CFLAGS"
+_LIB="$LIBS"
+CFLAGS="$CFLAGS $TREAD_CFLAGS"
+LIBS="$LIBS $THREAD_LIBS"
+
+
+
+for ac_func in strerror_r getpwuid_r gethostbyname_r
+do
+as_ac_var=`echo "ac_cv_func_$ac_func" | $as_tr_sh`
+echo "$as_me:$LINENO: checking for $ac_func" >&5
+echo $ECHO_N "checking for $ac_func... $ECHO_C" >&6
+if eval "test \"\${$as_ac_var+set}\" = set"; then
+  echo $ECHO_N "(cached) $ECHO_C" >&6
+else
+  cat >conftest.$ac_ext <<_ACEOF
+#line $LINENO "configure"
+#include "confdefs.h"
+/* System header to define __stub macros and hopefully few prototypes,
+    which can conflict with char $ac_func (); below.  */
+#include <assert.h>
+/* Override any gcc2 internal prototype to avoid an error.  */
+#ifdef __cplusplus
+extern "C"
+#endif
+/* We use char because int might match the return type of a gcc2
+   builtin and then its argument prototype would still apply.  */
+char $ac_func ();
+char (*f) ();
+
+#ifdef F77_DUMMY_MAIN
+#  ifdef __cplusplus
+     extern "C"
+#  endif
+   int F77_DUMMY_MAIN() { return 1; }
+#endif
+int
+main ()
+{
+/* The GNU C library defines this for functions which it implements
+    to always fail with ENOSYS.  Some functions are actually named
+    something starting with __ and the normal name is an alias.  */
+#if defined (__stub_$ac_func) || defined (__stub___$ac_func)
+choke me
+#else
+f = $ac_func;
+#endif
+
+  ;
+  return 0;
+}
+_ACEOF
+rm -f conftest.$ac_objext conftest$ac_exeext
+if { (eval echo "$as_me:$LINENO: \"$ac_link\"") >&5
+  (eval $ac_link) 2>&5
+  ac_status=$?
+  echo "$as_me:$LINENO: \$? = $ac_status" >&5
+  (exit $ac_status); } &&
+         { ac_try='test -s conftest$ac_exeext'
+  { (eval echo "$as_me:$LINENO: \"$ac_try\"") >&5
+  (eval $ac_try) 2>&5
+  ac_status=$?
+  echo "$as_me:$LINENO: \$? = $ac_status" >&5
+  (exit $ac_status); }; }; then
+  eval "$as_ac_var=yes"
+else
+  echo "$as_me: failed program was:" >&5
+cat conftest.$ac_ext >&5
+eval "$as_ac_var=no"
+fi
+rm -f conftest.$ac_objext conftest$ac_exeext conftest.$ac_ext
+fi
+echo "$as_me:$LINENO: result: `eval echo '${'$as_ac_var'}'`" >&5
+echo "${ECHO_T}`eval echo '${'$as_ac_var'}'`" >&6
+if test `eval echo '${'$as_ac_var'}'` = yes; then
+  cat >>confdefs.h <<_ACEOF
+#define `echo "HAVE_$ac_func" | $as_tr_cpp` 1
+_ACEOF
+
+fi
+done
+
+CFLAGS="$_CFLAGS"
+LIB="$_LIBS"
+
+
 
 # This test makes sure that run tests work at all.  Sometimes a shared
 # library is found by the linker, but the runtime linker can't find it.
@@ -17603,8 +17702,8 @@ s,@with_pam@,$with_pam,;t t
 s,@with_rendezvous@,$with_rendezvous,;t t
 s,@with_openssl@,$with_openssl,;t t
 s,@ELF_SYS@,$ELF_SYS,;t t
-s,@THREAD_LIBS@,$THREAD_LIBS,;t t
 s,@THREAD_CFLAGS@,$THREAD_CFLAGS,;t t
+s,@THREAD_LIBS@,$THREAD_LIBS,;t t
 s,@AWK@,$AWK,;t t
 s,@FLEX@,$FLEX,;t t
 s,@FLEXFLAGS@,$FLEXFLAGS,;t t

configure.in

@@ -1,5 +1,5 @@
 dnl Process this file with autoconf to produce a configure script.
-dnl $Header: /cvsroot/pgsql/configure.in,v 1.261 2003/06/13 23:10:07 momjian Exp $
+dnl $Header: /cvsroot/pgsql/configure.in,v 1.262 2003/06/14 14:35:42 momjian Exp $
 dnl
 dnl Developers, please strive to achieve this order:
 dnl
@@ -323,7 +323,9 @@ IFS=$ac_save_IFS
 # Enable libpq to be thread-safe
 #
 AC_MSG_CHECKING([allow threaded libpq])
-PGAC_ARG_BOOL(with, threads, no, [  --with-threads          allow libpq to be thread-safe])
+PGAC_ARG_BOOL(with, threads, no, [  --with-threads          allow libpq to be thread-safe],
+              [AC_DEFINE([USE_THREADS], 1, [Define to 1 to build libpq with threads. (--with-threads)])])
+
 AC_MSG_RESULT([$with_threads])
 AC_SUBST(with_threads)
 
@@ -559,9 +561,12 @@ case $host_os in
 			# these require no special flags or libraries
 			;;
 		freebsd2*|freebsd3*|freebsd4*) THREAD_CFLAGS="-pthread" ;;
-		freebsd*) THREAD_LIBS="-lc_r" ;;
+		freebsd*)
-		linux*) THREAD_LIBS="-lpthread"
+			THREAD_LIBS="-lc_r"
-			THREAD_CFLAGS="-D_REENTRANT" ;;
+			;;
+		linux*) THREAD_CFLAGS="-D_REENTRANT -D_THREAD_SAFE -D_POSIX_PTHREAD_SEMANTICS"
+			THREAD_LIBS="-lpthread"
+			;;
 		*)
 			# other operating systems might fail because they have pthread.h but need
 			# special libs we don't know about yet.
@@ -573,8 +578,8 @@ or libraries required for threading support.
 ])
 esac
 fi
-AC_SUBST(THREAD_LIBS)
 AC_SUBST(THREAD_CFLAGS)
+AC_SUBST(THREAD_LIBS)
 
 #
 # Assignments
@@ -983,6 +988,20 @@ AC_CHECK_FUNCS(atexit, [],
 
 AC_FUNC_FSEEKO
 
+#
+# Check for re-entrant versions of certain functions
+#
+# Include special flags if required
+#
+_CFLAGS="$CFLAGS"
+_LIB="$LIBS"
+CFLAGS="$CFLAGS $TREAD_CFLAGS"
+LIBS="$LIBS $THREAD_LIBS"
+AC_CHECK_FUNCS([strerror_r getpwuid_r gethostbyname_r])
+CFLAGS="$_CFLAGS"
+LIB="$_LIBS"
+
+
 
 # This test makes sure that run tests work at all.  Sometimes a shared
 # library is found by the linker, but the runtime linker can't find it.

src/Makefile.global.in

@@ -1,5 +1,5 @@
 # -*-makefile-*-
-# $Header: /cvsroot/pgsql/src/Makefile.global.in,v 1.163 2003/05/27 16:36:50 momjian Exp $
+# $Header: /cvsroot/pgsql/src/Makefile.global.in,v 1.164 2003/06/14 14:35:42 momjian Exp $
 
 #------------------------------------------------------------------------------
 # All PostgreSQL makefiles include this file and use the variables it sets,
@@ -121,6 +121,7 @@ localedir := @localedir@
 #
 # Records the choice of the various --enable-xxx and --with-xxx options.
 
+with_threads	= @with_threads@
 with_java	= @with_java@
 with_perl	= @with_perl@
 with_python	= @with_python@
@@ -340,7 +341,7 @@ endif
 #
 # substitute implementations of the C library
 
-LIBOBJS = @LIBOBJS@ path.o
+LIBOBJS = @LIBOBJS@ path.o threads.o
 
 ifneq (,$(LIBOBJS))
 LIBS += -lpgport

src/include/pg_config.h.in

@@ -121,6 +121,9 @@
 /* Define to 1 if you have the `getaddrinfo' function. */
 #undef HAVE_GETADDRINFO
 
+/* Define to 1 if you have the `gethostbyname_r' function. */
+#undef HAVE_GETHOSTBYNAME_R
+
 /* Define to 1 if you have the `gethostname' function. */
 #undef HAVE_GETHOSTNAME
 
@@ -136,6 +139,9 @@
 /* Define to 1 if you have the `getpeereid' function. */
 #undef HAVE_GETPEEREID
 
+/* Define to 1 if you have the `getpwuid_r' function. */
+#undef HAVE_GETPWUID_R
+
 /* Define to 1 if you have the `getrusage' function. */
 #undef HAVE_GETRUSAGE
 
@@ -375,6 +381,9 @@
 /* Define to 1 if you have the `strerror' function. */
 #undef HAVE_STRERROR
 
+/* Define to 1 if you have the `strerror_r' function. */
+#undef HAVE_STRERROR_R
+
 /* Define to 1 if cpp supports the ANSI # stringizing operator. */
 #undef HAVE_STRINGIZE
 
@@ -579,6 +588,9 @@
 /* Define to select SysV-style shared memory. */
 #undef USE_SYSV_SHARED_MEMORY
 
+/* Define to 1 to build libpq with threads. (--with-threads) */
+#undef USE_THREADS
+
 /* Define to select unnamed POSIX semaphores. */
 #undef USE_UNNAMED_POSIX_SEMAPHORES
 

src/include/port.h

@@ -6,11 +6,15 @@
  * Portions Copyright (c) 1996-2002, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $Id: port.h,v 1.6 2003/06/12 08:15:29 momjian Exp $
+ * $Id: port.h,v 1.7 2003/06/14 14:35:42 momjian Exp $
  *
  *-------------------------------------------------------------------------
  */
 
+/* for thread.c */
+#include <pwd.h>
+#include <netdb.h>
+
 /* Portable path handling for Unix/Win32 */
 bool is_absolute_path(const char *filename);
 char *first_path_separator(const char *filename);
@@ -98,3 +102,15 @@ extern long random(void);
 #ifndef HAVE_SRANDOM
 extern void srandom(unsigned int seed);
 #endif
+
+/* thread.h */
+extern char *pqStrerror(int errnum, char *strerrbuf, size_t buflen);
+
+extern int pqGetpwuid(uid_t uid, struct passwd *resultbuf, char *buffer,
+		      size_t buflen, struct passwd **result);
+
+extern int pqGethostbyname(const char *name,
+			   struct hostent *resbuf,
+			   char *buf, size_t buflen,
+			   struct hostent **result,
+			   int *herrno);

src/interfaces/libpq/Makefile

@@ -4,7 +4,7 @@
 #
 # Copyright (c) 1994, Regents of the University of California
 #
-# $Header: /cvsroot/pgsql/src/interfaces/libpq/Makefile,v 1.81 2003/06/12 17:31:50 momjian Exp $
+# $Header: /cvsroot/pgsql/src/interfaces/libpq/Makefile,v 1.82 2003/06/14 14:35:42 momjian Exp $
 #
 #-------------------------------------------------------------------------
 
@@ -23,7 +23,7 @@ override CPPFLAGS := -I$(srcdir) $(CPPFLAGS) $(THREAD_CFLAGS) -DFRONTEND -DSYSCO
 OBJS= fe-auth.o fe-connect.o fe-exec.o fe-misc.o fe-print.o fe-lobj.o \
       fe-protocol2.o fe-protocol3.o pqexpbuffer.o pqsignal.o fe-secure.o \
       dllist.o md5.o ip.o wchar.o encnames.o \
-      $(filter crypt.o getaddrinfo.o inet_aton.o snprintf.o strerror.o path.o, $(LIBOBJS))
+      $(filter crypt.o getaddrinfo.o inet_aton.o snprintf.o strerror.o path.o threads.o, $(LIBOBJS))
 
 
 # Add libraries that libpq depends (or might depend) on into the
@@ -46,9 +46,13 @@ backend_src = $(top_srcdir)/src/backend
 # For port modules, this only happens if configure decides the module
 # is needed (see filter hack in OBJS, above).
 
-crypt.c getaddrinfo.c inet_aton.c snprintf.c strerror.c path.c: %.c : $(top_srcdir)/src/port/%.c
+crypt.c getaddrinfo.c inet_aton.c snprintf.c strerror.c path.c threads.c: %.c : $(top_srcdir)/src/port/%.c
 	rm -f $@ && $(LN_S) $< .
 
+# compile this with thread flags
+thread.o: thread.c
+	$(CC) $(CFLAGS) $(THREAD_CFLAGS) -c thread.c
+
 dllist.c: $(backend_src)/lib/dllist.c
 	rm -f $@ && $(LN_S) $< .
 

src/port/Makefile

@@ -7,7 +7,7 @@
 # with broken/missing library files.
 
 # IDENTIFICATION
-#    $Header: /cvsroot/pgsql/src/port/Makefile,v 1.3 2002/07/27 20:10:05 petere Exp $
+#    $Header: /cvsroot/pgsql/src/port/Makefile,v 1.4 2003/06/14 14:35:42 momjian Exp $
 #
 #-------------------------------------------------------------------------
 
@@ -22,5 +22,8 @@ endif
 libpgport.a: $(LIBOBJS)
 	$(AR) crs $@ $^
 
+thread.o: thread.c
+	$(CC) $(CFLAGS) $(THREAD_CFLAGS) -c thread.c
+
 clean distclean maintainer-clean:
 	rm -f libpgport.a $(LIBOBJS)

src/port/threads.c

@@ -0,0 +1,85 @@
+/*-------------------------------------------------------------------------
+ *
+ * threads.c
+ *
+ *		  Prototypes and macros around system calls, used to help make
+ *		  threaded libraries reentrant and safe to use from threaded applications.
+ *
+ * Portions Copyright (c) 1996-2003, PostgreSQL Global Development Group
+ *
+ * $Id: threads.c,v 1.1 2003/06/14 14:35:42 momjian Exp $
+ *
+ *-------------------------------------------------------------------------
+ */
+
+#include "postgres.h"
+
+/*
+ * Wrapper around strerror and strerror_r to use the former if it is
+ * available and also return a more useful value (the error string).
+ */
+char *
+pqStrerror(int errnum, char *strerrbuf, size_t buflen)
+{
+#if defined(USE_THREADS) && defined(HAVE_STRERROR_R)
+	/* reentrant strerror_r is available */
+	/* some early standards had strerror_r returning char * */
+	strerror_r(errnum, strerrbuf, buflen);
+	return (strerrbuf);
+#else
+	/* no strerror_r() available, just use strerror */
+	return strerror(errnum);
+#endif
+}
+
+/*
+ * Wrapper around getpwuid() or getpwuid_r() to mimic POSIX getpwuid_r()
+ * behaviour, if it is not available.
+ */
+int
+pqGetpwuid(uid_t uid, struct passwd * resultbuf, char *buffer,
+		   size_t buflen, struct passwd ** result)
+{
+#if defined(USE_THREADS) && defined(HAVE_GETPWUID_R)
+	/*
+	 * broken (well early POSIX draft) getpwuid_r() which returns 'struct
+	 * passwd *'
+	 */
+	*result = getpwuid_r(uid, resultbuf, buffer, buflen);
+#else
+	/* no getpwuid_r() available, just use getpwuid() */
+	*result = getpwuid(uid);
+#endif
+	return (*result == NULL) ? -1 : 0;
+}
+
+/*
+ * Wrapper around gethostbyname() or gethostbyname_r() to mimic
+ * POSIX gethostbyname_r() behaviour, if it is not available.
+ */
+int
+pqGethostbyname(const char *name,
+				struct hostent * resbuf,
+				char *buf, size_t buflen,
+				struct hostent ** result,
+				int *herrno)
+{
+#if defined(USE_THREADS) && defined(HAVE_GETHOSTBYNAME_R)
+	/*
+	 * broken (well early POSIX draft) gethostbyname_r() which returns
+	 * 'struct hostent *'
+	 */
+	*result = gethostbyname_r(name, resbuf, buf, buflen, herrno);
+	return (*result == NULL) ? -1 : 0;
+#else
+	/* no gethostbyname_r(), just use gethostbyname() */
+	*result = gethostbyname(name);
+	if (*result != NULL)
+		return 0;
+	else
+	{
+		*herrno = h_errno;
+		return -1;
+	}
+#endif
+}