refactor!: rename NGX_RS_*_OFFSET constants to original names

This replaces the custom NGX_RS_HTTP_*_CONF_OFFSET constants with the
original NGX_HTTP_*_CONF_OFFSET.  NGX_RS_* constants were introduced as a
workaround because bindgen failed to translate NGX_HTTP_*_CONF_OFFSET.

examples/async.rs

@@ -9,7 +9,7 @@ use ngx::ffi::{
     ngx_array_push, ngx_command_t, ngx_conf_t, ngx_cycle, ngx_event_t, ngx_http_core_module, ngx_http_core_run_phases,
     ngx_http_handler_pt, ngx_http_module_t, ngx_http_phases_NGX_HTTP_ACCESS_PHASE, ngx_http_request_t, ngx_int_t,
     ngx_module_t, ngx_posted_events, ngx_queue_s, ngx_str_t, ngx_uint_t, NGX_CONF_TAKE1, NGX_HTTP_LOC_CONF,
-    NGX_HTTP_MODULE, NGX_RS_HTTP_LOC_CONF_OFFSET,
+    NGX_HTTP_LOC_CONF_OFFSET, NGX_HTTP_MODULE,
 };
 use ngx::http::{self, HTTPModule, MergeConfigError};
 use ngx::{http_request_handler, ngx_log_debug_http, ngx_null_command, ngx_string};
@@ -59,7 +59,7 @@ static mut NGX_HTTP_ASYNC_COMMANDS: [ngx_command_t; 2] = [
         name: ngx_string!("async"),
         type_: (NGX_HTTP_LOC_CONF | NGX_CONF_TAKE1) as ngx_uint_t,
         set: Some(ngx_http_async_commands_set_enable),
-        conf: NGX_RS_HTTP_LOC_CONF_OFFSET,
+        conf: NGX_HTTP_LOC_CONF_OFFSET,
         offset: 0,
         post: std::ptr::null_mut(),
     },

examples/awssig.rs

@@ -6,7 +6,7 @@ use ngx::core;
 use ngx::ffi::{
     ngx_array_push, ngx_command_t, ngx_conf_t, ngx_http_core_module, ngx_http_handler_pt, ngx_http_module_t,
     ngx_http_phases_NGX_HTTP_PRECONTENT_PHASE, ngx_int_t, ngx_module_t, ngx_str_t, ngx_uint_t, NGX_CONF_TAKE1,
-    NGX_HTTP_LOC_CONF, NGX_HTTP_MODULE, NGX_HTTP_SRV_CONF, NGX_RS_HTTP_LOC_CONF_OFFSET,
+    NGX_HTTP_LOC_CONF, NGX_HTTP_LOC_CONF_OFFSET, NGX_HTTP_MODULE, NGX_HTTP_SRV_CONF,
 };
 use ngx::http::*;
 use ngx::{http_request_handler, ngx_log_debug_http, ngx_null_command, ngx_string};
@@ -46,39 +46,39 @@ static mut NGX_HTTP_AWSSIGV4_COMMANDS: [ngx_command_t; 6] = [
         name: ngx_string!("awssigv4"),
         type_: (NGX_HTTP_LOC_CONF | NGX_HTTP_SRV_CONF | NGX_CONF_TAKE1) as ngx_uint_t,
         set: Some(ngx_http_awssigv4_commands_set_enable),
-        conf: NGX_RS_HTTP_LOC_CONF_OFFSET,
+        conf: NGX_HTTP_LOC_CONF_OFFSET,
         offset: 0,
         post: std::ptr::null_mut(),
     },
     ngx_command_t {
         name: ngx_string!("awssigv4_access_key"),
         type_: (NGX_HTTP_LOC_CONF | NGX_HTTP_SRV_CONF | NGX_CONF_TAKE1) as ngx_uint_t,
         set: Some(ngx_http_awssigv4_commands_set_access_key),
-        conf: NGX_RS_HTTP_LOC_CONF_OFFSET,
+        conf: NGX_HTTP_LOC_CONF_OFFSET,
         offset: 0,
         post: std::ptr::null_mut(),
     },
     ngx_command_t {
         name: ngx_string!("awssigv4_secret_key"),
         type_: (NGX_HTTP_LOC_CONF | NGX_HTTP_SRV_CONF | NGX_CONF_TAKE1) as ngx_uint_t,
         set: Some(ngx_http_awssigv4_commands_set_secret_key),
-        conf: NGX_RS_HTTP_LOC_CONF_OFFSET,
+        conf: NGX_HTTP_LOC_CONF_OFFSET,
         offset: 0,
         post: std::ptr::null_mut(),
     },
     ngx_command_t {
         name: ngx_string!("awssigv4_s3_bucket"),
         type_: (NGX_HTTP_LOC_CONF | NGX_HTTP_SRV_CONF | NGX_CONF_TAKE1) as ngx_uint_t,
         set: Some(ngx_http_awssigv4_commands_set_s3_bucket),
-        conf: NGX_RS_HTTP_LOC_CONF_OFFSET,
+        conf: NGX_HTTP_LOC_CONF_OFFSET,
         offset: 0,
         post: std::ptr::null_mut(),
     },
     ngx_command_t {
         name: ngx_string!("awssigv4_s3_endpoint"),
         type_: (NGX_HTTP_LOC_CONF | NGX_HTTP_SRV_CONF | NGX_CONF_TAKE1) as ngx_uint_t,
         set: Some(ngx_http_awssigv4_commands_set_s3_endpoint),
-        conf: NGX_RS_HTTP_LOC_CONF_OFFSET,
+        conf: NGX_HTTP_LOC_CONF_OFFSET,
         offset: 0,
         post: std::ptr::null_mut(),
     },

examples/curl.rs

@@ -5,7 +5,7 @@ use ngx::core;
 use ngx::ffi::{
     ngx_array_push, ngx_command_t, ngx_conf_t, ngx_http_core_module, ngx_http_handler_pt, ngx_http_module_t,
     ngx_http_phases_NGX_HTTP_ACCESS_PHASE, ngx_int_t, ngx_module_t, ngx_str_t, ngx_uint_t, NGX_CONF_TAKE1,
-    NGX_HTTP_LOC_CONF, NGX_HTTP_MODULE, NGX_RS_HTTP_LOC_CONF_OFFSET,
+    NGX_HTTP_LOC_CONF, NGX_HTTP_LOC_CONF_OFFSET, NGX_HTTP_MODULE,
 };
 use ngx::http::{self, HTTPModule, MergeConfigError};
 use ngx::{http_request_handler, ngx_log_debug_http, ngx_null_command, ngx_string};
@@ -41,7 +41,7 @@ static mut NGX_HTTP_CURL_COMMANDS: [ngx_command_t; 2] = [
         name: ngx_string!("curl"),
         type_: (NGX_HTTP_LOC_CONF | NGX_CONF_TAKE1) as ngx_uint_t,
         set: Some(ngx_http_curl_commands_set_enable),
-        conf: NGX_RS_HTTP_LOC_CONF_OFFSET,
+        conf: NGX_HTTP_LOC_CONF_OFFSET,
         offset: 0,
         post: std::ptr::null_mut(),
     },

examples/upstream.rs

@@ -17,7 +17,7 @@ use ngx::ffi::{
     ngx_http_module_t, ngx_http_upstream_init_peer_pt, ngx_http_upstream_init_pt, ngx_http_upstream_init_round_robin,
     ngx_http_upstream_module, ngx_http_upstream_srv_conf_t, ngx_http_upstream_t, ngx_int_t, ngx_module_t,
     ngx_peer_connection_t, ngx_str_t, ngx_uint_t, NGX_CONF_NOARGS, NGX_CONF_TAKE1, NGX_CONF_UNSET, NGX_ERROR,
-    NGX_HTTP_MODULE, NGX_HTTP_UPS_CONF, NGX_LOG_EMERG, NGX_RS_HTTP_SRV_CONF_OFFSET,
+    NGX_HTTP_MODULE, NGX_HTTP_SRV_CONF_OFFSET, NGX_HTTP_UPS_CONF, NGX_LOG_EMERG,
 };
 use ngx::http::{
     ngx_http_conf_get_module_srv_conf, ngx_http_conf_upstream_srv_conf_immutable,
@@ -93,7 +93,7 @@ static mut NGX_HTTP_UPSTREAM_CUSTOM_COMMANDS: [ngx_command_t; 2] = [
         name: ngx_string!("custom"),
         type_: (NGX_HTTP_UPS_CONF | NGX_CONF_NOARGS | NGX_CONF_TAKE1) as ngx_uint_t,
         set: Some(ngx_http_upstream_commands_set_custom),
-        conf: NGX_RS_HTTP_SRV_CONF_OFFSET,
+        conf: NGX_HTTP_SRV_CONF_OFFSET,
         offset: 0,
         post: std::ptr::null_mut(),
     },

nginx-sys/build/wrapper.h

@@ -3,11 +3,6 @@
 #include <ngx_config.h>
 #include <ngx_core.h>
 
-// Define as constants since bindgen can't parse these values
-const size_t NGX_RS_HTTP_MAIN_CONF_OFFSET = NGX_HTTP_MAIN_CONF_OFFSET;
-const size_t NGX_RS_HTTP_SRV_CONF_OFFSET = NGX_HTTP_SRV_CONF_OFFSET;
-const size_t NGX_RS_HTTP_LOC_CONF_OFFSET = NGX_HTTP_LOC_CONF_OFFSET;
-
 const char *NGX_RS_MODULE_SIGNATURE = NGX_MODULE_SIGNATURE;
 
 // `--prefix=` results in not emitting the declaration

nginx-sys/src/lib.rs

@@ -3,6 +3,7 @@
 #![no_std]
 
 use core::fmt;
+use core::mem::offset_of;
 use core::ptr::copy_nonoverlapping;
 use core::slice;
 
@@ -21,6 +22,19 @@ mod bindings {
 #[doc(no_inline)]
 pub use bindings::*;
 
+/// The offset of the `main_conf` field in the `ngx_http_conf_ctx_t` struct.
+///
+/// This is used to access the main configuration context for an HTTP module.
+pub const NGX_HTTP_MAIN_CONF_OFFSET: usize = offset_of!(ngx_http_conf_ctx_t, main_conf);
+/// The offset of the `srv_conf` field in the `ngx_http_conf_ctx_t` struct.
+///
+/// This is used to access the server configuration context for an HTTP module.
+pub const NGX_HTTP_SRV_CONF_OFFSET: usize = offset_of!(ngx_http_conf_ctx_t, srv_conf);
+/// The offset of the `loc_conf` field in the `ngx_http_conf_ctx_t` struct.
+///
+/// This is used to access the location configuration context for an HTTP module.
+pub const NGX_HTTP_LOC_CONF_OFFSET: usize = offset_of!(ngx_http_conf_ctx_t, loc_conf);
+
 /// Convert a byte slice to a raw pointer (`*mut u_char`) allocated in the given nginx memory pool.
 ///
 /// # Safety