Fix build, add guards and extract magic numbers

Author: alubbe

src/ngx_http_lua_common.h

@@ -22,6 +22,19 @@
 #include <lauxlib.h>
 
 
+#if (NGX_PCRE)
+
+#include <pcre.h>
+
+#if (PCRE_MAJOR > 8) || (PCRE_MAJOR == 8 && PCRE_MINOR >= 21)
+#   define LUA_HAVE_PCRE_JIT 1
+#else
+#   define LUA_HAVE_PCRE_JIT 0
+#endif
+
+#endif
+
+
 #if !defined(nginx_version) || (nginx_version < 1006000)
 #error at least nginx 1.6.0 is required but found an older version
 #endif
@@ -159,7 +172,11 @@ 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;
+
+#if (LUA_HAVE_PCRE_JIT)
+    pcre_jit_stack      *jit_stack;
+#endif
+
 #endif
 
     ngx_array_t         *shm_zones;  /* of ngx_shm_zone_t* */

src/ngx_http_lua_module.c

@@ -28,6 +28,18 @@
 #include "ngx_http_lua_ssl_certby.h"
 
 
+#if (NGX_PCRE)
+
+#if (PCRE_MAJOR > 8) || (PCRE_MAJOR == 8 && PCRE_MINOR >= 21)
+#   define LUA_HAVE_PCRE_JIT 1
+#   define NGX_LUA_RE_MIN_JIT_STACK_SIZE 32 * 1024
+#else
+#   define LUA_HAVE_PCRE_JIT 0
+#endif
+
+#endif
+
+
 static void *ngx_http_lua_create_main_conf(ngx_conf_t *cf);
 static char *ngx_http_lua_init_main_conf(ngx_conf_t *cf, void *conf);
 static void *ngx_http_lua_create_srv_conf(ngx_conf_t *cf);
@@ -798,7 +810,12 @@ ngx_http_lua_create_main_conf(ngx_conf_t *cf)
 #if (NGX_PCRE)
     lmcf->regex_cache_max_entries = NGX_CONF_UNSET;
     lmcf->regex_match_limit = NGX_CONF_UNSET;
-    lmcf->jit_stack = pcre_jit_stack_alloc(32*1024, 32*1024);
+
+#if (LUA_HAVE_PCRE_JIT)
+    lmcf->jit_stack = pcre_jit_stack_alloc(NGX_LUA_RE_MIN_JIT_STACK_SIZE,
+                                           NGX_LUA_RE_MIN_JIT_STACK_SIZE);
+#endif
+
 #endif
     lmcf->postponed_to_rewrite_phase_end = NGX_CONF_UNSET;
     lmcf->postponed_to_access_phase_end = NGX_CONF_UNSET;

src/ngx_http_lua_regex.c

@@ -42,6 +42,8 @@
 
 #define NGX_LUA_RE_DFA_MODE_WORKSPACE_COUNT (100)
 
+#define NGX_LUA_RE_MIN_JIT_STACK_SIZE 32 * 1024
+
 
 typedef struct {
 #ifndef NGX_LUA_NO_FFI_API
@@ -2481,20 +2483,21 @@ 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) {
+    if (size < NGX_LUA_RE_MIN_JIT_STACK_SIZE) {
         return;
     }
+
+    lmcf = ngx_http_cycle_get_module_main_conf(ngx_cycle,
+                                               ngx_http_lua_module);
     pcre_jit_stack_free(lmcf->jit_stack);
-    lmcf->jit_stack = pcre_jit_stack_alloc(min_size, size);
+    lmcf->jit_stack = pcre_jit_stack_alloc(NGX_LUA_RE_MIN_JIT_STACK_SIZE,
+                                           size);
 }
 #endif /* NGX_LUA_NO_FFI_API */