WIP: Add jit_stack_size option

Author: alubbe

src/ngx_http_lua_common.h

@@ -159,6 +159,7 @@ struct ngx_http_lua_main_conf_s {
     ngx_int_t            regex_cache_entries;
     ngx_int_t            regex_cache_max_entries;
     ngx_int_t            regex_match_limit;
+    pcre_jit_stack       jit_stack;
 #endif
 
     ngx_array_t         *shm_zones;  /* of ngx_shm_zone_t* */

src/ngx_http_lua_regex.c

@@ -363,6 +363,7 @@ ngx_http_lua_ngx_re_match_helper(lua_State *L, int wantcaps)
         old_pool = ngx_http_lua_pcre_malloc_init(pool);
 
         sd = pcre_study(re_comp.regex, PCRE_STUDY_JIT_COMPILE, &msg);
+        pcre_assign_jit_stack(sd, NULL, lmcf->jit_stack);
 
         ngx_http_lua_pcre_malloc_done(old_pool);
 
@@ -825,6 +826,7 @@ ngx_http_lua_ngx_re_gmatch(lua_State *L)
         old_pool = ngx_http_lua_pcre_malloc_init(pool);
 
         sd = pcre_study(re_comp.regex, PCRE_STUDY_JIT_COMPILE, &msg);
+        pcre_assign_jit_stack(sd, NULL, lmcf->jit_stack);
 
         ngx_http_lua_pcre_malloc_done(old_pool);
 
@@ -2478,6 +2480,22 @@ ngx_http_lua_ffi_max_regex_cache_size(void)
     }
     return (uint32_t) lmcf->regex_cache_max_entries;
 }
+
+void
+ngx_http_lua_ffi_set_jit_stack_size(int size)
+{
+    int                          min_size;
+    ngx_http_lua_main_conf_t    *lmcf;
+
+    min_size = MIN(32 * 1024, size);
+    lmcf = ngx_http_cycle_get_module_main_conf(ngx_cycle,
+                                               ngx_http_lua_module);
+    if (lmcf == NULL) {
+        return;
+    }
+    pcre_jit_stack_free(lmcf->jit_stack);
+    lmcf->jit_stack = pcre_jit_stack_alloc(min_size, size);
+}
 #endif /* NGX_LUA_NO_FFI_API */