view auto/cc/conf @ 9300:5be23505292b default tip

SSI: fixed incorrect or duplicate stub output. Following 3518:eb3aaf8bd2a9 (0.8.37), r->request_output is only set if there are data in the first buffer sent in the subrequest. As a result, following the change mentioned this flag cannot be used to prevent duplicate ngx_http_ssi_stub_output() calls, since it is not set if there was already some output, but the first buffer was empty. Still, when there are multiple subrequests, even an empty subrequest response might be delayed by the postpone filter, leading to a second call of ngx_http_ssi_stub_output() during finalization from ngx_http_writer() the subreqest buffers are released by the postpone filter. Since r->request_output is not set after the first call, this resulted in duplicate stub output. Additionally, checking only the first buffer might be wrong in some unusual cases. For example, the first buffer might be empty if $r->flush() is called before printing any data in the embedded Perl module. Depending on the postpone_output value and corresponding sizes, this issue can result in either duplicate or unexpected stub output, or "zero size buf in writer" alerts. Following 8124:f5515e727656 (1.23.4), it became slightly easier to reproduce the issue, as empty static files and empty cache items now result in a response with an empty buffer. Before the change, an empty proxied response can be used to reproduce the issue. Fix is check all buffers and set r->request_output if any non-empty buffers are sent. This ensures that all unusual cases of non-empty responses are covered, and also that r->request_output will be set after the first stub output, preventing duplicate output. Reported by Jan Gassen.
author Maxim Dounin <mdounin@mdounin.ru>
date Thu, 04 Jul 2024 17:41:28 +0300
parents 9bcc5cc94ff4
children
line wrap: on
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# Copyright (C) Igor Sysoev
# Copyright (C) Nginx, Inc.


LINK="\$(CC)"

MAIN_LINK=
MODULE_LINK="-shared"

ngx_include_opt="-I "
ngx_compile_opt="-c"
ngx_pic_opt="-fPIC"
ngx_objout="-o "
ngx_binout="-o "
ngx_objext="o"
ngx_binext=
ngx_modext=".so"

ngx_long_start=
ngx_long_end=

ngx_regex_dirsep="\/"
ngx_dirsep='/'

ngx_regex_cont=' \\\
	'
ngx_cont=' \
	'
ngx_tab=' \
		'
ngx_spacer=

ngx_long_regex_cont=$ngx_regex_cont
ngx_long_cont=$ngx_cont

. auto/cc/name

if test -n "$CFLAGS"; then

    CC_TEST_FLAGS="$CFLAGS $NGX_CC_OPT"

    case $NGX_CC_NAME in

        ccc)
            # Compaq C V6.5-207

            ngx_include_opt="-I"
        ;;

        sunc)

            MAIN_LINK=
            MODULE_LINK="-G"

            case "$NGX_MACHINE" in

                i86pc)
                    NGX_AUX=" src/os/unix/ngx_sunpro_x86.il"
                ;;

                sun4u | sun4v)
                    NGX_AUX=" src/os/unix/ngx_sunpro_sparc64.il"
                ;;

            esac

            case $CPU in

                amd64)
                    NGX_AUX=" src/os/unix/ngx_sunpro_amd64.il"
                ;;

            esac
        ;;

    esac

else

    case $NGX_CC_NAME in
        gcc)
            # gcc 2.7.2.3, 2.8.1, 2.95.4, egcs-1.1.2
            #     3.0.4, 3.1.1, 3.2.3, 3.3.2, 3.3.3, 3.3.4, 3.4.0, 3.4.2
            #     4.0.0, 4.0.1, 4.1.0

            . auto/cc/gcc
        ;;

        clang)
            # Clang C compiler

            . auto/cc/clang
        ;;

        icc)
            # Intel C++ compiler 7.1, 8.0, 8.1

            . auto/cc/icc
        ;;

        sunc)
            # Sun C 5.7 Patch 117837-04 2005/05/11

            . auto/cc/sunc
        ;;

        ccc)
            # Compaq C V6.5-207

            . auto/cc/ccc
        ;;

        acc)
            # aCC: HP ANSI C++ B3910B A.03.55.02

            . auto/cc/acc
        ;;

        msvc)
            # MSVC++ 6.0 SP2, MSVC++ Toolkit 2003

            . auto/cc/msvc
        ;;

        owc)
            # Open Watcom C 1.0, 1.2

            . auto/cc/owc
        ;;

        bcc)
            # Borland C++ 5.5

            . auto/cc/bcc
        ;;

    esac

    CC_TEST_FLAGS="$CC_TEST_FLAGS $NGX_CC_OPT"

fi

CFLAGS="$CFLAGS $NGX_CC_OPT"
NGX_TEST_LD_OPT="$NGX_LD_OPT"

if [ "$NGX_PLATFORM" != win32 ]; then

    if test -n "$NGX_LD_OPT"; then
        ngx_feature=--with-ld-opt=\"$NGX_LD_OPT\"
        ngx_feature_name=
        ngx_feature_run=no
        ngx_feature_incs=
        ngx_feature_path=
        ngx_feature_libs=
        ngx_feature_test=
        . auto/feature

        if [ $ngx_found = no ]; then
            echo $0: error: the invalid value in --with-ld-opt=\"$NGX_LD_OPT\"
            echo
            exit 1
        fi
    fi


    ngx_feature="-Wl,-E switch"
    ngx_feature_name=
    ngx_feature_run=no
    ngx_feature_incs=
    ngx_feature_path=
    ngx_feature_libs=-Wl,-E
    ngx_feature_test=
    . auto/feature

    if [ $ngx_found = yes ]; then
        MAIN_LINK="-Wl,-E"
    fi


    if [ "$NGX_CC_NAME" = "sunc" ]; then
        echo "checking for gcc builtin atomic operations ... disabled"
    else
        ngx_feature="gcc builtin atomic operations"
        ngx_feature_name=NGX_HAVE_GCC_ATOMIC
        ngx_feature_run=yes
        ngx_feature_incs=
        ngx_feature_path=
        ngx_feature_libs=
        ngx_feature_test="long  n = 0;
                          if (!__sync_bool_compare_and_swap(&n, 0, 1))
                              return 1;
                          if (__sync_fetch_and_add(&n, 1) != 1)
                              return 1;
                          if (n != 2)
                              return 1;
                          __sync_synchronize();"
        . auto/feature
    fi


    if [ "$NGX_CC_NAME" = "ccc" ]; then
        echo "checking for C99 variadic macros ... disabled"
    else
        ngx_feature="C99 variadic macros"
        ngx_feature_name="NGX_HAVE_C99_VARIADIC_MACROS"
        ngx_feature_run=yes
        ngx_feature_incs="#include <stdio.h>
#define var(dummy, ...)  sprintf(__VA_ARGS__)"
        ngx_feature_path=
        ngx_feature_libs=
        ngx_feature_test="char  buf[30]; buf[0] = '0';
                          var(0, buf, \"%d\", 1);
                          if (buf[0] != '1') return 1"
        . auto/feature
    fi


    ngx_feature="gcc variadic macros"
    ngx_feature_name="NGX_HAVE_GCC_VARIADIC_MACROS"
    ngx_feature_run=yes
    ngx_feature_incs="#include <stdio.h>
#define var(dummy, args...)  sprintf(args)"
    ngx_feature_path=
    ngx_feature_libs=
    ngx_feature_test="char  buf[30]; buf[0] = '0';
                      var(0, buf, \"%d\", 1);
                      if (buf[0] != '1') return 1"
    . auto/feature


    ngx_feature="gcc builtin 64 bit byteswap"
    ngx_feature_name="NGX_HAVE_GCC_BSWAP64"
    ngx_feature_run=no
    ngx_feature_incs=
    ngx_feature_path=
    ngx_feature_libs=
    ngx_feature_test="if (__builtin_bswap64(0)) return 1"
    . auto/feature


#    ngx_feature="inline"
#    ngx_feature_name=
#    ngx_feature_run=no
#    ngx_feature_incs="int inline f(void) { return 1 }"
#    ngx_feature_path=
#    ngx_feature_libs=
#    ngx_feature_test=
#    . auto/feature
#
#    if [ $ngx_found = yes ]; then
#    fi

fi