ext/unicorn_http/common_field_optimization.h

   1 #ifndef common_field_optimization
   2 #define common_field_optimization
   3 #include "ruby.h"
   4
   5 struct common_field {
   6   const signed long len;
   7   const char *name;
   8   VALUE value;
   9 };
  10
  11 /*
  12  * A list of common HTTP headers we expect to receive.
  13  * This allows us to avoid repeatedly creating identical string
  14  * objects to be used with rb_hash_aset().
  15  */
  16 static struct common_field common_http_fields[] = {
  17 # define f(N) { (sizeof(N) - 1), N, Qnil }
  18   f("ACCEPT"),
  19   f("ACCEPT_CHARSET"),
  20   f("ACCEPT_ENCODING"),
  21   f("ACCEPT_LANGUAGE"),
  22   f("ALLOW"),
  23   f("AUTHORIZATION"),
  24   f("CACHE_CONTROL"),
  25   f("CONNECTION"),
  26   f("CONTENT_ENCODING"),
  27   f("CONTENT_LENGTH"),
  28   f("CONTENT_TYPE"),
  29   f("COOKIE"),
  30   f("DATE"),
  31   f("EXPECT"),
  32   f("FROM"),
  33   f("HOST"),
  34   f("IF_MATCH"),
  35   f("IF_MODIFIED_SINCE"),
  36   f("IF_NONE_MATCH"),
  37   f("IF_RANGE"),
  38   f("IF_UNMODIFIED_SINCE"),
  39   f("KEEP_ALIVE"), /* Firefox sends this */
  40   f("MAX_FORWARDS"),
  41   f("PRAGMA"),
  42   f("PROXY_AUTHORIZATION"),
  43   f("RANGE"),
  44   f("REFERER"),
  45   f("TE"),
  46   f("TRAILER"),
  47   f("TRANSFER_ENCODING"),
  48   f("UPGRADE"),
  49   f("USER_AGENT"),
  50   f("VIA"),
  51   f("X_FORWARDED_FOR"), /* common for proxies */
  52   f("X_FORWARDED_PROTO"), /* common for proxies */
  53   f("X_REAL_IP"), /* common for proxies */
  54   f("WARNING")
  55 # undef f
  56 };
  57
  58 #define HTTP_PREFIX "HTTP_"
  59 #define HTTP_PREFIX_LEN (sizeof(HTTP_PREFIX) - 1)
  60
  61 /* this function is not performance-critical, called only at load time */
  62 static void init_common_fields(void)
  63 {
  64   int i;
  65   struct common_field *cf = common_http_fields;
  66   char tmp[64];
  67   memcpy(tmp, HTTP_PREFIX, HTTP_PREFIX_LEN);
  68
  69   for(i = 0; i < ARRAY_SIZE(common_http_fields); cf++, i++) {
  70     /* Rack doesn't like certain headers prefixed with "HTTP_" */
  71     if (!strcmp("CONTENT_LENGTH", cf->name) ||
  72         !strcmp("CONTENT_TYPE", cf->name)) {
  73       cf->value = rb_str_new(cf->name, cf->len);
  74     } else {
  75       memcpy(tmp + HTTP_PREFIX_LEN, cf->name, cf->len + 1);
  76       cf->value = rb_str_new(tmp, HTTP_PREFIX_LEN + cf->len);
  77     }
  78     cf->value = rb_obj_freeze(cf->value);
  79     rb_global_variable(&cf->value);
  80   }
  81 }
  82
  83 /* this function is called for every header set */
  84 static VALUE find_common_field_value(const char *field, size_t flen)
  85 {
  86   int i;
  87   struct common_field *cf = common_http_fields;
  88
  89   for(i = 0; i < ARRAY_SIZE(common_http_fields); i++, cf++) {
  90     if (cf->len == flen && !memcmp(cf->name, field, flen))
  91       return cf->value;
  92   }
  93   return Qnil;
  94 }
  95
  96 #endif /* common_field_optimization_h */