doc: clearify the missing the closing long bracket may due to the lua code is too long.

Author: doujiang24

README.markdown

@@ -908,6 +908,8 @@ As noted earlier, PCRE sequences presented within `*_by_lua_block {}` directives
  # evaluates to "1234"
 ```
 
+**NOTE** You are recommended to use `by_lua_file` when the Lua code is very long.
+
 [Back to TOC](#table-of-contents)
 
 Mixing with SSI Not Supported

doc/HttpLuaModule.wiki

@@ -755,6 +755,8 @@ As noted earlier, PCRE sequences presented within <code>*_by_lua_block {}</code>
     # evaluates to "1234"
 </geshi>
 
+'''NOTE''' You are recommended to use `by_lua_file` when the Lua code is very long.
+
 == Mixing with SSI Not Supported ==
 
 Mixing SSI with ngx_lua in the same Nginx request is not supported at all. Just use ngx_lua exclusively. Everything you can do with SSI can be done atop ngx_lua anyway and it can be more efficient when using ngx_lua.

src/ngx_http_lua_directive.c

@@ -1537,7 +1537,7 @@ ngx_http_lua_conf_read_lua_token(ngx_conf_t *cf,
     for ( ;; ) {
 
         if (b->pos >= b->last
-            || (b->last - b->pos < (b->end - b->start) / 3
+            || (b->last - b->pos < (b->end - b->start) / 2
                 && cf->conf_file->file.offset < file_size))
         {
 
@@ -1709,7 +1709,8 @@ ngx_http_lua_conf_read_lua_token(ngx_conf_t *cf,
             if (q == NULL) {
                 ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                                    "Lua code block missing the closing "
-                                   "long bracket \"%*s\"",
+                                   "long bracket \"%*s\", "
+                                   "the inlined Lua code may be too long",
                                    b->pos + ovec[1] - p, p);
                 return NGX_ERROR;
             }

t/132-lua-blocks.t

@@ -312,7 +312,7 @@ hello, world
 [error]
 --- must_die
 --- error_log eval
-qr/\[emerg\] .*? Lua code block missing the closing long bracket "]]" in .*?\bnginx\.conf:41/
+qr/\[emerg\] .*? Lua code block missing the closing long bracket "]]", the inlined Lua code may be too long in .*?\bnginx\.conf:41/
 
 
 
@@ -331,7 +331,7 @@ hello, world
 [error]
 --- must_die
 --- error_log eval
-qr/\[emerg\] .*? Lua code block missing the closing long bracket "]==]" in .*?\bnginx\.conf:41/
+qr/\[emerg\] .*? Lua code block missing the closing long bracket "]==]", the inlined Lua code may be too long in .*?\bnginx.conf:41/
 
 
 
@@ -350,7 +350,7 @@ hello, world
 [error]
 --- must_die
 --- error_log eval
-qr/\[emerg\] .*? Lua code block missing the closing long bracket "]]" in .*?\bnginx\.conf:41/
+qr/\[emerg\] .*? Lua code block missing the closing long bracket "]]", the inlined Lua code may be too long in .*?\bnginx\.conf:41/
 
 
 
@@ -369,7 +369,7 @@ hello, world
 [error]
 --- must_die
 --- error_log eval
-qr/\[emerg\] .*? Lua code block missing the closing long bracket "]=]" in .*?\bnginx\.conf:41/
+qr/\[emerg\] .*? Lua code block missing the closing long bracket "]=]", the inlined Lua code may be too long in .*?\bnginx\.conf:41/