SSL: workaround for incorrect SSL_write() errors in OpenSSL 1.1.1. OpenSSL 1.1.1 fails to return SSL_ERROR_SYSCALL if an error happens during SSL_write() after close_notify alert from the peer, and returns SSL_ERROR_ZERO_RETURN instead. Broken by this commit, which removes the "i == 0" check around the SSL_RECEIVED_SHUTDOWN one: https://git.openssl.org/?p=openssl.git;a=commitdiff;h=8051ab2 In particular, if a client closed the connection without reading the response but with properly sent close_notify alert, this resulted in unexpected "SSL_write() failed while ..." critical log message instead of correct "SSL_write() failed (32: Broken pipe)" at the info level. Since SSL_ERROR_ZERO_RETURN cannot be legitimately returned after SSL_write(), the fix is to convert all SSL_ERROR_ZERO_RETURN errors after SSL_write() to SSL_ERROR_SYSCALL.

# Copyright (C) Igor Sysoev
# Copyright (C) Nginx, Inc.


NGX_MAKEFILE=$NGX_OBJS/Makefile
NGX_MODULES_C=$NGX_OBJS/ngx_modules.c

NGX_AUTO_HEADERS_H=$NGX_OBJS/ngx_auto_headers.h
NGX_AUTO_CONFIG_H=$NGX_OBJS/ngx_auto_config.h

NGX_AUTOTEST=$NGX_OBJS/autotest
NGX_AUTOCONF_ERR=$NGX_OBJS/autoconf.err

# STUBs
NGX_ERR=$NGX_OBJS/autoconf.err
MAKEFILE=$NGX_OBJS/Makefile


NGX_PCH=
NGX_USE_PCH=


# check the echo's "-n" option and "\c" capability

if echo "test\c" | grep c >/dev/null; then

    if echo -n test | grep n >/dev/null; then
        ngx_n=
        ngx_c=

    else
        ngx_n=-n
        ngx_c=
    fi

else
    ngx_n=
    ngx_c='\c'
fi


# create Makefile

cat << END > Makefile

default:	build

clean:
	rm -rf Makefile $NGX_OBJS
END