vendor/libssh2-sys-0.3.0/libssh2/acinclude.m4 - toolchain/rustc - Git at Google


 dnl **********************************************************************
 dnl CURL_DETECT_ICC ([ACTION-IF-YES])
 dnl
 dnl check if this is the Intel ICC compiler, and if so run the ACTION-IF-YES
 dnl sets the $ICC variable to "yes" or "no"
 dnl **********************************************************************
 AC_DEFUN([CURL_DETECT_ICC],
 [
     ICC="no"
     AC_MSG_CHECKING([for icc in use])
     if test "$GCC" = "yes"; then
        dnl check if this is icc acting as gcc in disguise
        AC_EGREP_CPP([^__INTEL_COMPILER], [__INTEL_COMPILER],
          dnl action if the text is found, this it has not been replaced by the
          dnl cpp
          ICC="no",
          dnl the text was not found, it was replaced by the cpp
          ICC="yes"
          AC_MSG_RESULT([yes])
          [$1]
        )
     fi
     if test "$ICC" = "no"; then
         # this is not ICC
         AC_MSG_RESULT([no])
     fi
 ])

 dnl We create a function for detecting which compiler we use and then set as
 dnl pendantic compiler options as possible for that particular compiler. The
 dnl options are only used for debug-builds.

 AC_DEFUN([CURL_CC_DEBUG_OPTS],
 [
     if test "z$ICC" = "z"; then
       CURL_DETECT_ICC
     fi

     if test "$GCC" = "yes"; then

        dnl figure out gcc version!
        AC_MSG_CHECKING([gcc version])
        gccver=`$CC -dumpversion`
        num1=`echo $gccver | cut -d . -f1`
        num2=`echo $gccver | cut -d . -f2`
        gccnum=`(expr $num1 "*" 100 + $num2) 2>/dev/null`
        AC_MSG_RESULT($gccver)

        if test "$ICC" = "yes"; then
          dnl this is icc, not gcc.

          dnl ICC warnings we ignore:
          dnl * 269 warns on our "%Od" printf formatters for curl_off_t output:
          dnl   "invalid format string conversion"
          dnl * 279 warns on static conditions in while expressions
          dnl * 981 warns on "operands are evaluated in unspecified order"
          dnl * 1418 "external definition with no prior declaration"
          dnl * 1419 warns on "external declaration in primary source file"
          dnl   which we know and do on purpose.

          WARN="-wd279,269,981,1418,1419"

          if test "$gccnum" -gt "600"; then
             dnl icc 6.0 and older doesn't have the -Wall flag
             WARN="-Wall $WARN"
          fi
        else dnl $ICC = yes
          dnl this is a set of options we believe *ALL* gcc versions support:
          WARN="-W -Wall -Wwrite-strings -pedantic -Wpointer-arith -Wnested-externs -Winline -Wmissing-prototypes"

          dnl -Wcast-align is a bit too annoying on all gcc versions ;-)

          if test "$gccnum" -ge "207"; then
            dnl gcc 2.7 or later
            WARN="$WARN -Wmissing-declarations"
          fi

          if test "$gccnum" -gt "295"; then
            dnl only if the compiler is newer than 2.95 since we got lots of
            dnl "`_POSIX_C_SOURCE' is not defined" in system headers with
            dnl gcc 2.95.4 on FreeBSD 4.9!
            WARN="$WARN -Wundef -Wno-long-long -Wsign-compare"
          fi

          if test "$gccnum" -ge "296"; then
            dnl gcc 2.96 or later
            WARN="$WARN -Wfloat-equal"
          fi

          if test "$gccnum" -gt "296"; then
            dnl this option does not exist in 2.96
            WARN="$WARN -Wno-format-nonliteral"
          fi

          dnl -Wunreachable-code seems totally unreliable on my gcc 3.3.2 on
          dnl on i686-Linux as it gives us heaps with false positives.
          dnl Also, on gcc 4.0.X it is totally unbearable and complains all
          dnl over making it unusable for generic purposes. Let's not use it.

          if test "$gccnum" -ge "303"; then
            dnl gcc 3.3 and later
            WARN="$WARN -Wendif-labels -Wstrict-prototypes"
          fi

          if test "$gccnum" -ge "304"; then
            # try these on gcc 3.4
            WARN="$WARN -Wdeclaration-after-statement"
          fi

          for flag in $CPPFLAGS; do
            case "$flag" in
             -I*)
               dnl Include path, provide a -isystem option for the same dir
               dnl to prevent warnings in those dirs. The -isystem was not very
               dnl reliable on earlier gcc versions.
               add=`echo $flag | sed 's/^-I/-isystem /g'`
               WARN="$WARN $add"
               ;;
            esac
          done

        fi dnl $ICC = no

        CFLAGS="$CFLAGS $WARN"

       AC_MSG_NOTICE([Added this set of compiler options: $WARN])

     else dnl $GCC = yes

       AC_MSG_NOTICE([Added no extra compiler options])

     fi dnl $GCC = yes

     dnl strip off optimizer flags
     NEWFLAGS=""
     for flag in $CFLAGS; do
       case "$flag" in
       -O*)
         dnl echo "cut off $flag"
         ;;
       *)
         NEWFLAGS="$NEWFLAGS $flag"
         ;;
       esac
     done
     CFLAGS=$NEWFLAGS

 ]) dnl end of AC_DEFUN()

 dnl CURL_CHECK_NONBLOCKING_SOCKET
 dnl -------------------------------------------------
 dnl Check for how to set a socket to non-blocking state. There seems to exist
 dnl four known different ways, with the one used almost everywhere being POSIX
 dnl and XPG3, while the other different ways for different systems (old BSD,
 dnl Windows and Amiga).
 dnl
 dnl There are two known platforms (AIX 3.x and SunOS 4.1.x) where the
 dnl O_NONBLOCK define is found but does not work. This condition is attempted
 dnl to get caught in this script by using an excessive number of #ifdefs...
 dnl
 AC_DEFUN([CURL_CHECK_NONBLOCKING_SOCKET],
 [
   AC_MSG_CHECKING([non-blocking sockets style])

   AC_TRY_COMPILE([
 /* headers for O_NONBLOCK test */
 #include <sys/types.h>
 #include <unistd.h>
 #include <fcntl.h>
 ],[
 /* try to compile O_NONBLOCK */

 #if defined(sun) || defined(__sun__) || defined(__SUNPRO_C) || defined(__SUNPRO_CC)
 # if defined(__SVR4) || defined(__srv4__)
 #  define PLATFORM_SOLARIS
 # else
 #  define PLATFORM_SUNOS4
 # endif
 #endif
 #if (defined(_AIX) || defined(__xlC__)) && !defined(_AIX41)
 # define PLATFORM_AIX_V3
 #endif

 #if defined(PLATFORM_SUNOS4) || defined(PLATFORM_AIX_V3) || defined(__BEOS__)
 #error "O_NONBLOCK does not work on this platform"
 #endif
   int socket;
   int flags = fcntl(socket, F_SETFL, flags | O_NONBLOCK);
 ],[
 dnl the O_NONBLOCK test was fine
 nonblock="O_NONBLOCK"
 AC_DEFINE(HAVE_O_NONBLOCK, 1, [use O_NONBLOCK for non-blocking sockets])
 ],[
 dnl the code was bad, try a different program now, test 2

   AC_TRY_COMPILE([
 /* headers for FIONBIO test */
 #include <unistd.h>
 #include <stropts.h>
 ],[
 /* FIONBIO source test (old-style unix) */
  int socket;
  int flags = ioctl(socket, FIONBIO, &flags);
 ],[
 dnl FIONBIO test was good
 nonblock="FIONBIO"
 AC_DEFINE(HAVE_FIONBIO, 1, [use FIONBIO for non-blocking sockets])
 ],[
 dnl FIONBIO test was also bad
 dnl the code was bad, try a different program now, test 3

   AC_TRY_COMPILE([
 /* headers for ioctlsocket test (Windows) */
 #undef inline
 #ifdef HAVE_WINDOWS_H
 #ifndef WIN32_LEAN_AND_MEAN
 #define WIN32_LEAN_AND_MEAN
 #endif
 #include <windows.h>
 #ifdef HAVE_WINSOCK2_H
 #include <winsock2.h>
 #else
 #ifdef HAVE_WINSOCK_H
 #include <winsock.h>
 #endif
 #endif
 #endif
 ],[
 /* ioctlsocket source code */
  SOCKET sd;
  unsigned long flags = 0;
  sd = socket(0, 0, 0);
  ioctlsocket(sd, FIONBIO, &flags);
 ],[
 dnl ioctlsocket test was good
 nonblock="ioctlsocket"
 AC_DEFINE(HAVE_IOCTLSOCKET, 1, [use ioctlsocket() for non-blocking sockets])
 ],[
 dnl ioctlsocket didnt compile!, go to test 4

   AC_TRY_LINK([
 /* headers for IoctlSocket test (Amiga?) */
 #include <sys/ioctl.h>
 ],[
 /* IoctlSocket source code */
  int socket;
  int flags = IoctlSocket(socket, FIONBIO, (long)1);
 ],[
 dnl ioctlsocket test was good
 nonblock="IoctlSocket"
 AC_DEFINE(HAVE_IOCTLSOCKET_CASE, 1, [use Ioctlsocket() for non-blocking sockets])
 ],[
 dnl Ioctlsocket didnt compile, do test 5!
   AC_TRY_COMPILE([
 /* headers for SO_NONBLOCK test (BeOS) */
 #include <socket.h>
 ],[
 /* SO_NONBLOCK source code */
  long b = 1;
  int socket;
  int flags = setsockopt(socket, SOL_SOCKET, SO_NONBLOCK, &b, sizeof(b));
 ],[
 dnl the SO_NONBLOCK test was good
 nonblock="SO_NONBLOCK"
 AC_DEFINE(HAVE_SO_NONBLOCK, 1, [use SO_NONBLOCK for non-blocking sockets])
 ],[
 dnl test 5 didnt compile!
 nonblock="nada"
 AC_DEFINE(HAVE_DISABLED_NONBLOCKING, 1, [disabled non-blocking sockets])
 ])
 dnl end of fifth test

 ])
 dnl end of forth test

 ])
 dnl end of third test

 ])
 dnl end of second test

 ])
 dnl end of non-blocking try-compile test
   AC_MSG_RESULT($nonblock)

   if test "$nonblock" = "nada"; then
     AC_MSG_WARN([non-block sockets disabled])
   fi
 ])

 dnl CURL_CHECK_NEED_REENTRANT_SYSTEM
 dnl -------------------------------------------------
 dnl Checks if the preprocessor _REENTRANT definition
 dnl must be unconditionally done for this platform.
 dnl Internal macro for CURL_CONFIGURE_REENTRANT.

 AC_DEFUN([CURL_CHECK_NEED_REENTRANT_SYSTEM], [
   case $host in
     *-*-solaris* | *-*-hpux*)
       tmp_need_reentrant="yes"
       ;;
     *)
       tmp_need_reentrant="no"
       ;;
   esac
 ])


 dnl CURL_CONFIGURE_FROM_NOW_ON_WITH_REENTRANT
 dnl -------------------------------------------------
 dnl This macro ensures that configuration tests done
 dnl after this will execute with preprocessor symbol
 dnl _REENTRANT defined. This macro also ensures that
 dnl the generated config file defines NEED_REENTRANT
 dnl and that in turn setup.h will define _REENTRANT.
 dnl Internal macro for CURL_CONFIGURE_REENTRANT.

 AC_DEFUN([CURL_CONFIGURE_FROM_NOW_ON_WITH_REENTRANT], [
 AC_DEFINE(NEED_REENTRANT, 1,
   [Define to 1 if _REENTRANT preprocessor symbol must be defined.])
 cat >>confdefs.h <<_EOF
 #ifndef _REENTRANT
 #  define _REENTRANT
 #endif
 _EOF
 ])


 dnl CURL_CONFIGURE_REENTRANT
 dnl -------------------------------------------------
 dnl This first checks if the preprocessor _REENTRANT
 dnl symbol is already defined. If it isn't currently
 dnl defined a set of checks are performed to verify
 dnl if its definition is required to make visible to
 dnl the compiler a set of *_r functions. Finally, if
 dnl _REENTRANT is already defined or needed it takes
 dnl care of making adjustments necessary to ensure
 dnl that it is defined equally for further configure
 dnl tests and generated config file.

 AC_DEFUN([CURL_CONFIGURE_REENTRANT], [
   AC_PREREQ([2.50])dnl
   #
   AC_MSG_CHECKING([if _REENTRANT is already defined])
   AC_COMPILE_IFELSE([
     AC_LANG_PROGRAM([[
     ]],[[
 #ifdef _REENTRANT
       int dummy=1;
 #else
       force compilation error
 #endif
     ]])
   ],[
     AC_MSG_RESULT([yes])
     tmp_reentrant_initially_defined="yes"
   ],[
     AC_MSG_RESULT([no])
     tmp_reentrant_initially_defined="no"
   ])
   #
   if test "$tmp_reentrant_initially_defined" = "no"; then
     AC_MSG_CHECKING([if _REENTRANT is actually needed])
     CURL_CHECK_NEED_REENTRANT_SYSTEM

     if test "$tmp_need_reentrant" = "yes"; then
       AC_MSG_RESULT([yes])
     else
       AC_MSG_RESULT([no])
     fi
   fi
   #
   AC_MSG_CHECKING([if _REENTRANT is onwards defined])
   if test "$tmp_reentrant_initially_defined" = "yes" ||
     test "$tmp_need_reentrant" = "yes"; then
     CURL_CONFIGURE_FROM_NOW_ON_WITH_REENTRANT
     AC_MSG_RESULT([yes])
   else
     AC_MSG_RESULT([no])
   fi
   #
 ])

 dnl LIBSSH2_LIB_HAVE_LINKFLAGS
 dnl --------------------------
 dnl Wrapper around AC_LIB_HAVE_LINKFLAGS to also check $prefix/lib, if set.
 dnl
 dnl autoconf only checks $prefix/lib64 if gcc -print-search-dirs output
 dnl includes a directory named lib64. So, to find libraries in $prefix/lib
 dnl we append -L$prefix/lib to LDFLAGS before checking.
 dnl
 dnl For conveniece, $4 is expanded if [lib]$1 is found.

 AC_DEFUN([LIBSSH2_LIB_HAVE_LINKFLAGS], [
   libssh2_save_CPPFLAGS="$CPPFLAGS"
   libssh2_save_LDFLAGS="$LDFLAGS"

   if test "${with_lib$1_prefix+set}" = set; then
     CPPFLAGS="$CPPFLAGS${CPPFLAGS:+ }-I${with_lib$1_prefix}/include"
     LDFLAGS="$LDFLAGS${LDFLAGS:+ }-L${with_lib$1_prefix}/lib"
   fi

   AC_LIB_HAVE_LINKFLAGS([$1], [$2], [$3])

   LDFLAGS="$libssh2_save_LDFLAGS"

   if test "$ac_cv_lib$1" = "yes"; then :
     $4
   else
     CPPFLAGS="$libssh2_save_CPPFLAGS"
   fi
 ])

 AC_DEFUN([LIBSSH2_CHECK_CRYPTO], [
 if test "$use_crypto" = "auto" && test "$found_crypto" = "none" || test "$use_crypto" = "$1"; then
 m4_case([$1],
 [openssl], [
   LIBSSH2_LIB_HAVE_LINKFLAGS([ssl], [crypto], [#include <openssl/ssl.h>], [
     AC_DEFINE(LIBSSH2_OPENSSL, 1, [Use $1])
     LIBSREQUIRED="$LIBSREQUIRED${LIBSREQUIRED:+ }libssl libcrypto"

     # Not all OpenSSL have AES-CTR functions.
     libssh2_save_LIBS="$LIBS"
     LIBS="$LIBS $LIBSSL"
     AC_CHECK_FUNCS(EVP_aes_128_ctr)
     LIBS="$libssh2_save_LIBS"

     found_crypto="$1"
     found_crypto_str="OpenSSL (AES-CTR: ${ac_cv_func_EVP_aes_128_ctr:-N/A})"
   ])
 ],

 [wolfssl], [
   if test "${with_libwolfssl_prefix+set}" = set; then
     CPPFLAGS="$CPPFLAGS${CPPFLAGS:+ }-I${with_libwolfssl_prefix}/include/wolfssl"
   else
     AC_MSG_ERROR([When using wolfSSL, must specify prefix with --with-libwolfssl-prefix in order to find OpenSSL compatibility headers.])
   fi
   LIBSSH2_LIB_HAVE_LINKFLAGS([wolfssl], [], [#include <wolfssl/options.h>], [
     AC_DEFINE(LIBSSH2_WOLFSSL, 1, [Use $1])
     LIBSREQUIRED="$LIBSREQUIRED${LIBSREQUIRED:+ }libwolfssl"
     found_crypto="$1"
   ])
 ],

 [libgcrypt], [
   LIBSSH2_LIB_HAVE_LINKFLAGS([gcrypt], [], [#include <gcrypt.h>], [
     AC_DEFINE(LIBSSH2_LIBGCRYPT, 1, [Use $1])
     found_crypto="$1"
   ])
 ],

 [mbedtls], [
   LIBSSH2_LIB_HAVE_LINKFLAGS([mbedcrypto], [], [#include <mbedtls/version.h>], [
     AC_DEFINE(LIBSSH2_MBEDTLS, 1, [Use $1])
     LIBS="$LIBS -lmbedcrypto"
     found_crypto="$1"
     support_clear_memory=yes
   ])
 ],

 [wincng], [
   # Look for Windows Cryptography API: Next Generation

   AC_CHECK_HEADERS([ntdef.h ntstatus.h], [], [], [#include <windows.h>])
   AC_CHECK_DECLS([SecureZeroMemory], [], [], [#include <windows.h>])

   LIBSSH2_LIB_HAVE_LINKFLAGS([crypt32], [], [
     #include <windows.h>
     #include <wincrypt.h>
   ])
   LIBSSH2_LIB_HAVE_LINKFLAGS([bcrypt], [], [
     #include <windows.h>
     #include <bcrypt.h>
   ], [
     AC_DEFINE(LIBSSH2_WINCNG, 1, [Use $1])
     found_crypto="$1"
     found_crypto_str="Windows Cryptography API: Next Generation"
     support_clear_memory="$ac_cv_have_decl_SecureZeroMemory"
   ])
 ],
 )
   test "$found_crypto" = "none" &&
     crypto_errors="${crypto_errors}No $1 crypto library found!
 "
 fi
 ])


 dnl LIBSSH2_CHECK_OPTION_WERROR
 dnl -------------------------------------------------
 dnl Verify if configure has been invoked with option
 dnl --enable-werror or --disable-werror, and set
 dnl shell variable want_werror as appropriate.

 AC_DEFUN([LIBSSH2_CHECK_OPTION_WERROR], [
   AC_BEFORE([$0],[LIBSSH2_CHECK_COMPILER])dnl
   AC_MSG_CHECKING([whether to enable compiler warnings as errors])
   OPT_COMPILER_WERROR="default"
   AC_ARG_ENABLE(werror,
 AC_HELP_STRING([--enable-werror],[Enable compiler warnings as errors])
 AC_HELP_STRING([--disable-werror],[Disable compiler warnings as errors]),
   OPT_COMPILER_WERROR=$enableval)
   case "$OPT_COMPILER_WERROR" in
     no)
       dnl --disable-werror option used
       want_werror="no"
       ;;
     default)
       dnl configure option not specified
       want_werror="no"
       ;;
     *)
       dnl --enable-werror option used
       want_werror="yes"
       ;;
   esac
   AC_MSG_RESULT([$want_werror])

   if test X"$want_werror" = Xyes; then
     CFLAGS="$CFLAGS -Werror"
   fi
 ])

	dnl **********************************************************************
	dnl CURL_DETECT_ICC ([ACTION-IF-YES])
	dnl
	dnl check if this is the Intel ICC compiler, and if so run the ACTION-IF-YES
	dnl sets the $ICC variable to "yes" or "no"
	dnl **********************************************************************
	AC_DEFUN([CURL_DETECT_ICC],
	[
	ICC="no"
	AC_MSG_CHECKING([for icc in use])
	if test "$GCC" = "yes"; then
	dnl check if this is icc acting as gcc in disguise
	AC_EGREP_CPP([^__INTEL_COMPILER], [__INTEL_COMPILER],
	dnl action if the text is found, this it has not been replaced by the
	dnl cpp
	ICC="no",
	dnl the text was not found, it was replaced by the cpp
	ICC="yes"
	AC_MSG_RESULT([yes])
	[$1]
	)
	fi
	if test "$ICC" = "no"; then
	# this is not ICC
	AC_MSG_RESULT([no])
	fi
	])

	dnl We create a function for detecting which compiler we use and then set as
	dnl pendantic compiler options as possible for that particular compiler. The
	dnl options are only used for debug-builds.

	AC_DEFUN([CURL_CC_DEBUG_OPTS],
	[
	if test "z$ICC" = "z"; then
	CURL_DETECT_ICC
	fi

	if test "$GCC" = "yes"; then

	dnl figure out gcc version!
	AC_MSG_CHECKING([gcc version])
	gccver=`$CC -dumpversion`
	num1=`echo $gccver \| cut -d . -f1`
	num2=`echo $gccver \| cut -d . -f2`
	gccnum=`(expr $num1 "*" 100 + $num2) 2>/dev/null`
	AC_MSG_RESULT($gccver)

	if test "$ICC" = "yes"; then
	dnl this is icc, not gcc.

	dnl ICC warnings we ignore:
	dnl * 269 warns on our "%Od" printf formatters for curl_off_t output:
	dnl "invalid format string conversion"
	dnl * 279 warns on static conditions in while expressions
	dnl * 981 warns on "operands are evaluated in unspecified order"
	dnl * 1418 "external definition with no prior declaration"
	dnl * 1419 warns on "external declaration in primary source file"
	dnl which we know and do on purpose.

	WARN="-wd279,269,981,1418,1419"

	if test "$gccnum" -gt "600"; then
	dnl icc 6.0 and older doesn't have the -Wall flag
	WARN="-Wall $WARN"
	fi
	else dnl $ICC = yes
	dnl this is a set of options we believe ALL gcc versions support:
	WARN="-W -Wall -Wwrite-strings -pedantic -Wpointer-arith -Wnested-externs -Winline -Wmissing-prototypes"

	dnl -Wcast-align is a bit too annoying on all gcc versions ;-)

	if test "$gccnum" -ge "207"; then
	dnl gcc 2.7 or later
	WARN="$WARN -Wmissing-declarations"
	fi

	if test "$gccnum" -gt "295"; then
	dnl only if the compiler is newer than 2.95 since we got lots of
	dnl "`_POSIX_C_SOURCE' is not defined" in system headers with
	dnl gcc 2.95.4 on FreeBSD 4.9!
	WARN="$WARN -Wundef -Wno-long-long -Wsign-compare"
	fi

	if test "$gccnum" -ge "296"; then
	dnl gcc 2.96 or later
	WARN="$WARN -Wfloat-equal"
	fi

	if test "$gccnum" -gt "296"; then
	dnl this option does not exist in 2.96
	WARN="$WARN -Wno-format-nonliteral"
	fi

	dnl -Wunreachable-code seems totally unreliable on my gcc 3.3.2 on
	dnl on i686-Linux as it gives us heaps with false positives.
	dnl Also, on gcc 4.0.X it is totally unbearable and complains all
	dnl over making it unusable for generic purposes. Let's not use it.

	if test "$gccnum" -ge "303"; then
	dnl gcc 3.3 and later
	WARN="$WARN -Wendif-labels -Wstrict-prototypes"
	fi

	if test "$gccnum" -ge "304"; then
	# try these on gcc 3.4
	WARN="$WARN -Wdeclaration-after-statement"
	fi

	for flag in $CPPFLAGS; do
	case "$flag" in
	-I*)
	dnl Include path, provide a -isystem option for the same dir
	dnl to prevent warnings in those dirs. The -isystem was not very
	dnl reliable on earlier gcc versions.
	add=`echo $flag \| sed 's/^-I/-isystem /g'`
	WARN="$WARN $add"
	;;
	esac
	done

	fi dnl $ICC = no

	CFLAGS="$CFLAGS $WARN"

	AC_MSG_NOTICE([Added this set of compiler options: $WARN])

	else dnl $GCC = yes

	AC_MSG_NOTICE([Added no extra compiler options])

	fi dnl $GCC = yes

	dnl strip off optimizer flags
	NEWFLAGS=""
	for flag in $CFLAGS; do
	case "$flag" in
	-O*)
	dnl echo "cut off $flag"
	;;
	*)
	NEWFLAGS="$NEWFLAGS $flag"
	;;
	esac
	done
	CFLAGS=$NEWFLAGS

	]) dnl end of AC_DEFUN()

	dnl CURL_CHECK_NONBLOCKING_SOCKET
	dnl -------------------------------------------------
	dnl Check for how to set a socket to non-blocking state. There seems to exist
	dnl four known different ways, with the one used almost everywhere being POSIX
	dnl and XPG3, while the other different ways for different systems (old BSD,
	dnl Windows and Amiga).
	dnl
	dnl There are two known platforms (AIX 3.x and SunOS 4.1.x) where the
	dnl O_NONBLOCK define is found but does not work. This condition is attempted
	dnl to get caught in this script by using an excessive number of #ifdefs...
	dnl
	AC_DEFUN([CURL_CHECK_NONBLOCKING_SOCKET],
	[
	AC_MSG_CHECKING([non-blocking sockets style])

	AC_TRY_COMPILE([
	/* headers for O_NONBLOCK test */
	#include <sys/types.h>
	#include <unistd.h>
	#include <fcntl.h>
	],[
	/* try to compile O_NONBLOCK */

	#if defined(sun) \|\| defined(__sun__) \|\| defined(__SUNPRO_C) \|\| defined(__SUNPRO_CC)
	# if defined(__SVR4) \|\| defined(__srv4__)
	# define PLATFORM_SOLARIS
	# else
	# define PLATFORM_SUNOS4
	# endif
	#endif
	#if (defined(_AIX) \|\| defined(__xlC__)) && !defined(_AIX41)
	# define PLATFORM_AIX_V3
	#endif

	#if defined(PLATFORM_SUNOS4) \|\| defined(PLATFORM_AIX_V3) \|\| defined(__BEOS__)
	#error "O_NONBLOCK does not work on this platform"
	#endif
	int socket;
	int flags = fcntl(socket, F_SETFL, flags \| O_NONBLOCK);
	],[
	dnl the O_NONBLOCK test was fine
	nonblock="O_NONBLOCK"
	AC_DEFINE(HAVE_O_NONBLOCK, 1, [use O_NONBLOCK for non-blocking sockets])
	],[
	dnl the code was bad, try a different program now, test 2

	AC_TRY_COMPILE([
	/* headers for FIONBIO test */
	#include <unistd.h>
	#include <stropts.h>
	],[
	/* FIONBIO source test (old-style unix) */
	int socket;
	int flags = ioctl(socket, FIONBIO, &flags);
	],[
	dnl FIONBIO test was good
	nonblock="FIONBIO"
	AC_DEFINE(HAVE_FIONBIO, 1, [use FIONBIO for non-blocking sockets])
	],[
	dnl FIONBIO test was also bad
	dnl the code was bad, try a different program now, test 3

	AC_TRY_COMPILE([
	/* headers for ioctlsocket test (Windows) */
	#undef inline
	#ifdef HAVE_WINDOWS_H
	#ifndef WIN32_LEAN_AND_MEAN
	#define WIN32_LEAN_AND_MEAN
	#endif
	#include <windows.h>
	#ifdef HAVE_WINSOCK2_H
	#include <winsock2.h>
	#else
	#ifdef HAVE_WINSOCK_H
	#include <winsock.h>
	#endif
	#endif
	#endif
	],[
	/* ioctlsocket source code */
	SOCKET sd;
	unsigned long flags = 0;
	sd = socket(0, 0, 0);
	ioctlsocket(sd, FIONBIO, &flags);
	],[
	dnl ioctlsocket test was good
	nonblock="ioctlsocket"
	AC_DEFINE(HAVE_IOCTLSOCKET, 1, [use ioctlsocket() for non-blocking sockets])
	],[
	dnl ioctlsocket didnt compile!, go to test 4

	AC_TRY_LINK([
	/* headers for IoctlSocket test (Amiga?) */
	#include <sys/ioctl.h>
	],[
	/* IoctlSocket source code */
	int socket;
	int flags = IoctlSocket(socket, FIONBIO, (long)1);
	],[
	dnl ioctlsocket test was good
	nonblock="IoctlSocket"
	AC_DEFINE(HAVE_IOCTLSOCKET_CASE, 1, [use Ioctlsocket() for non-blocking sockets])
	],[
	dnl Ioctlsocket didnt compile, do test 5!
	AC_TRY_COMPILE([
	/* headers for SO_NONBLOCK test (BeOS) */
	#include <socket.h>
	],[
	/* SO_NONBLOCK source code */
	long b = 1;
	int socket;
	int flags = setsockopt(socket, SOL_SOCKET, SO_NONBLOCK, &b, sizeof(b));
	],[
	dnl the SO_NONBLOCK test was good
	nonblock="SO_NONBLOCK"
	AC_DEFINE(HAVE_SO_NONBLOCK, 1, [use SO_NONBLOCK for non-blocking sockets])
	],[
	dnl test 5 didnt compile!
	nonblock="nada"
	AC_DEFINE(HAVE_DISABLED_NONBLOCKING, 1, [disabled non-blocking sockets])
	])
	dnl end of fifth test

	])
	dnl end of forth test

	])
	dnl end of third test

	])
	dnl end of second test

	])
	dnl end of non-blocking try-compile test
	AC_MSG_RESULT($nonblock)

	if test "$nonblock" = "nada"; then
	AC_MSG_WARN([non-block sockets disabled])
	fi
	])

	dnl CURL_CHECK_NEED_REENTRANT_SYSTEM
	dnl -------------------------------------------------
	dnl Checks if the preprocessor _REENTRANT definition
	dnl must be unconditionally done for this platform.
	dnl Internal macro for CURL_CONFIGURE_REENTRANT.

	AC_DEFUN([CURL_CHECK_NEED_REENTRANT_SYSTEM], [
	case $host in
	--solaris* \| --hpux*)
	tmp_need_reentrant="yes"
	;;
	*)
	tmp_need_reentrant="no"
	;;
	esac
	])


	dnl CURL_CONFIGURE_FROM_NOW_ON_WITH_REENTRANT
	dnl -------------------------------------------------
	dnl This macro ensures that configuration tests done
	dnl after this will execute with preprocessor symbol
	dnl _REENTRANT defined. This macro also ensures that
	dnl the generated config file defines NEED_REENTRANT
	dnl and that in turn setup.h will define _REENTRANT.
	dnl Internal macro for CURL_CONFIGURE_REENTRANT.

	AC_DEFUN([CURL_CONFIGURE_FROM_NOW_ON_WITH_REENTRANT], [
	AC_DEFINE(NEED_REENTRANT, 1,
	[Define to 1 if _REENTRANT preprocessor symbol must be defined.])
	cat >>confdefs.h <<_EOF
	#ifndef _REENTRANT
	# define _REENTRANT
	#endif
	_EOF
	])


	dnl CURL_CONFIGURE_REENTRANT
	dnl -------------------------------------------------
	dnl This first checks if the preprocessor _REENTRANT
	dnl symbol is already defined. If it isn't currently
	dnl defined a set of checks are performed to verify
	dnl if its definition is required to make visible to
	dnl the compiler a set of *_r functions. Finally, if
	dnl _REENTRANT is already defined or needed it takes
	dnl care of making adjustments necessary to ensure
	dnl that it is defined equally for further configure
	dnl tests and generated config file.

	AC_DEFUN([CURL_CONFIGURE_REENTRANT], [
	AC_PREREQ([2.50])dnl
	#
	AC_MSG_CHECKING([if _REENTRANT is already defined])
	AC_COMPILE_IFELSE([
	AC_LANG_PROGRAM([[
	]],[[
	#ifdef _REENTRANT
	int dummy=1;
	#else
	force compilation error
	#endif
	]])
	],[
	AC_MSG_RESULT([yes])
	tmp_reentrant_initially_defined="yes"
	],[
	AC_MSG_RESULT([no])
	tmp_reentrant_initially_defined="no"
	])
	#
	if test "$tmp_reentrant_initially_defined" = "no"; then
	AC_MSG_CHECKING([if _REENTRANT is actually needed])
	CURL_CHECK_NEED_REENTRANT_SYSTEM

	if test "$tmp_need_reentrant" = "yes"; then
	AC_MSG_RESULT([yes])
	else
	AC_MSG_RESULT([no])
	fi
	fi
	#
	AC_MSG_CHECKING([if _REENTRANT is onwards defined])
	if test "$tmp_reentrant_initially_defined" = "yes" \|\|
	test "$tmp_need_reentrant" = "yes"; then
	CURL_CONFIGURE_FROM_NOW_ON_WITH_REENTRANT
	AC_MSG_RESULT([yes])
	else
	AC_MSG_RESULT([no])
	fi
	#
	])

	dnl LIBSSH2_LIB_HAVE_LINKFLAGS
	dnl --------------------------
	dnl Wrapper around AC_LIB_HAVE_LINKFLAGS to also check $prefix/lib, if set.
	dnl
	dnl autoconf only checks $prefix/lib64 if gcc -print-search-dirs output
	dnl includes a directory named lib64. So, to find libraries in $prefix/lib
	dnl we append -L$prefix/lib to LDFLAGS before checking.
	dnl
	dnl For conveniece, $4 is expanded if [lib]$1 is found.

	AC_DEFUN([LIBSSH2_LIB_HAVE_LINKFLAGS], [
	libssh2_save_CPPFLAGS="$CPPFLAGS"
	libssh2_save_LDFLAGS="$LDFLAGS"

	if test "${with_lib$1_prefix+set}" = set; then
	CPPFLAGS="$CPPFLAGS${CPPFLAGS:+ }-I${with_lib$1_prefix}/include"
	LDFLAGS="$LDFLAGS${LDFLAGS:+ }-L${with_lib$1_prefix}/lib"
	fi

	AC_LIB_HAVE_LINKFLAGS([$1], [$2], [$3])

	LDFLAGS="$libssh2_save_LDFLAGS"

	if test "$ac_cv_lib$1" = "yes"; then :
	$4
	else
	CPPFLAGS="$libssh2_save_CPPFLAGS"
	fi
	])

	AC_DEFUN([LIBSSH2_CHECK_CRYPTO], [
	if test "$use_crypto" = "auto" && test "$found_crypto" = "none" \|\| test "$use_crypto" = "$1"; then
	m4_case([$1],
	[openssl], [
	LIBSSH2_LIB_HAVE_LINKFLAGS([ssl], [crypto], [#include <openssl/ssl.h>], [
	AC_DEFINE(LIBSSH2_OPENSSL, 1, [Use $1])
	LIBSREQUIRED="$LIBSREQUIRED${LIBSREQUIRED:+ }libssl libcrypto"

	# Not all OpenSSL have AES-CTR functions.
	libssh2_save_LIBS="$LIBS"
	LIBS="$LIBS $LIBSSL"
	AC_CHECK_FUNCS(EVP_aes_128_ctr)
	LIBS="$libssh2_save_LIBS"

	found_crypto="$1"
	found_crypto_str="OpenSSL (AES-CTR: ${ac_cv_func_EVP_aes_128_ctr:-N/A})"
	])
	],

	[wolfssl], [
	if test "${with_libwolfssl_prefix+set}" = set; then
	CPPFLAGS="$CPPFLAGS${CPPFLAGS:+ }-I${with_libwolfssl_prefix}/include/wolfssl"
	else
	AC_MSG_ERROR([When using wolfSSL, must specify prefix with --with-libwolfssl-prefix in order to find OpenSSL compatibility headers.])
	fi
	LIBSSH2_LIB_HAVE_LINKFLAGS([wolfssl], [], [#include <wolfssl/options.h>], [
	AC_DEFINE(LIBSSH2_WOLFSSL, 1, [Use $1])
	LIBSREQUIRED="$LIBSREQUIRED${LIBSREQUIRED:+ }libwolfssl"
	found_crypto="$1"
	])
	],

	[libgcrypt], [
	LIBSSH2_LIB_HAVE_LINKFLAGS([gcrypt], [], [#include <gcrypt.h>], [
	AC_DEFINE(LIBSSH2_LIBGCRYPT, 1, [Use $1])
	found_crypto="$1"
	])
	],

	[mbedtls], [
	LIBSSH2_LIB_HAVE_LINKFLAGS([mbedcrypto], [], [#include <mbedtls/version.h>], [
	AC_DEFINE(LIBSSH2_MBEDTLS, 1, [Use $1])
	LIBS="$LIBS -lmbedcrypto"
	found_crypto="$1"
	support_clear_memory=yes
	])
	],

	[wincng], [
	# Look for Windows Cryptography API: Next Generation

	AC_CHECK_HEADERS([ntdef.h ntstatus.h], [], [], [#include <windows.h>])
	AC_CHECK_DECLS([SecureZeroMemory], [], [], [#include <windows.h>])

	LIBSSH2_LIB_HAVE_LINKFLAGS([crypt32], [], [
	#include <windows.h>
	#include <wincrypt.h>
	])
	LIBSSH2_LIB_HAVE_LINKFLAGS([bcrypt], [], [
	#include <windows.h>
	#include <bcrypt.h>
	], [
	AC_DEFINE(LIBSSH2_WINCNG, 1, [Use $1])
	found_crypto="$1"
	found_crypto_str="Windows Cryptography API: Next Generation"
	support_clear_memory="$ac_cv_have_decl_SecureZeroMemory"
	])
	],
	)
	test "$found_crypto" = "none" &&
	crypto_errors="${crypto_errors}No $1 crypto library found!
	"
	fi
	])


	dnl LIBSSH2_CHECK_OPTION_WERROR
	dnl -------------------------------------------------
	dnl Verify if configure has been invoked with option
	dnl --enable-werror or --disable-werror, and set
	dnl shell variable want_werror as appropriate.

	AC_DEFUN([LIBSSH2_CHECK_OPTION_WERROR], [
	AC_BEFORE([$0],[LIBSSH2_CHECK_COMPILER])dnl
	AC_MSG_CHECKING([whether to enable compiler warnings as errors])
	OPT_COMPILER_WERROR="default"
	AC_ARG_ENABLE(werror,
	AC_HELP_STRING([--enable-werror],[Enable compiler warnings as errors])
	AC_HELP_STRING([--disable-werror],[Disable compiler warnings as errors]),
	OPT_COMPILER_WERROR=$enableval)
	case "$OPT_COMPILER_WERROR" in
	no)
	dnl --disable-werror option used
	want_werror="no"
	;;
	default)
	dnl configure option not specified
	want_werror="no"
	;;
	*)
	dnl --enable-werror option used
	want_werror="yes"
	;;
	esac
	AC_MSG_RESULT([$want_werror])

	if test X"$want_werror" = Xyes; then
	CFLAGS="$CFLAGS -Werror"
	fi
	])