[core] fix POST with chunked request body (fixes #2854)

(thx the_jk)

x-ref:
  "chunked transfer encoding in request body only works for tiny chunks"
  https://redmine.lighttpd.net/issues/2854

src/connections-glue.c

@@ -132,7 +132,7 @@ static handler_t connection_handle_read_post_chunked(server *srv, connection *co
                 off_t hsz = p + 1 - (c->mem->ptr+c->offset);
                 unsigned char *s = (unsigned char *)c->mem->ptr+c->offset;
                 for (unsigned char u;(u=(unsigned char)hex2int(*s))!=0xFF;++s) {
-                    if (te_chunked > (~((off_t)-1) >> 4)) {
+                    if (te_chunked > (off_t)(1uL<<(8*sizeof(off_t)-5))-1) {
                         log_error_write(srv, __FILE__, __LINE__, "s",
                                         "chunked data size too large -> 400");
                         /* 400 Bad Request */

tests/request.t

@@ -8,7 +8,7 @@ BEGIN {
 
 use strict;
 use IO::Socket;
-use Test::More tests => 59;
+use Test::More tests => 60;
 use LightyTest;
 
 my $tf = LightyTest->new();
@@ -167,6 +167,22 @@ Connection: close
 Content-Type: application/x-www-form-urlencoded
 Transfer-Encoding: chunked
 
+10
+0123456789abcdef
+0
+
+EOF
+ );
+$t->{RESPONSE} = [ { 'HTTP-Protocol' => 'HTTP/1.1', 'HTTP-Status' => 200 } ];
+ok($tf->handle_http($t) == 0, 'POST via Transfer-Encoding: chunked, two hex');
+
+$t->{REQUEST}  = ( <<EOF
+POST /get-post-len.pl HTTP/1.1
+Host: www.example.org
+Connection: close
+Content-Type: application/x-www-form-urlencoded
+Transfer-Encoding: chunked
+
 a
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