Use hash table for dynamic table lookup

lib/nghttp2_hd.h

@@ -126,15 +126,25 @@ typedef enum {
   NGHTTP2_HD_FLAG_VALUE_GIFT = 1 << 3
 } nghttp2_hd_flags;
 
-typedef struct {
+struct nghttp2_hd_entry;
+typedef struct nghttp2_hd_entry nghttp2_hd_entry;
+
+struct nghttp2_hd_entry {
   nghttp2_nv nv;
+  /* The next entry which shares same bucket in hash table. */
+  nghttp2_hd_entry *next;
+  /* The sequence number.  We will increment it by one whenever we
+     store nghttp2_hd_entry to dynamic header table. */
+  uint32_t seq;
+  /* The hash value for header name (nv.name). */
+  uint32_t hash;
   /* nghttp2_token value for nv.name.  It could be -1 if we have no
      token for that header field name. */
   int token;
   /* Reference count */
   uint8_t ref;
   uint8_t flags;
-} nghttp2_hd_entry;
+};
 
 typedef struct {
   nghttp2_hd_entry **buffer;
@@ -183,14 +193,21 @@ typedef struct {
   size_t hd_table_bufsize;
   /* The effective header table size. */
   size_t hd_table_bufsize_max;
+  /* Next sequence number for nghttp2_hd_entry */
+  uint32_t next_seq;
   /* If inflate/deflate error occurred, this value is set to 1 and
      further invocation of inflate/deflate will fail with
      NGHTTP2_ERR_HEADER_COMP. */
   uint8_t bad;
 } nghttp2_hd_context;
 
+#define HD_MAP_SIZE 128
+
+typedef struct { nghttp2_hd_entry *table[HD_MAP_SIZE]; } nghttp2_hd_map;
+
 struct nghttp2_hd_deflater {
   nghttp2_hd_context ctx;
+  nghttp2_hd_map map;
   /* The upper limit of the header table size the deflater accepts. */
   size_t deflate_hd_table_bufsize_max;
   /* Minimum header table size notified in the next context update */

mkstatichdtbl.py

@@ -10,6 +10,17 @@
 from __future__ import unicode_literals
 import re, sys
 
+def hd_map_hash(name):
+  h = 2166136261
+
+  # FNV hash variant: http://isthe.com/chongo/tech/comp/fnv/
+  for c in name:
+    h ^= ord(c)
+    h *= 16777619
+    h &= 0xffffffff
+
+  return h
+
 entries = []
 for line in sys.stdin:
     m = re.match(r'(\d+)\s+(\S+)\s+(\S.*)?', line)
@@ -21,6 +32,6 @@ idx = 0
 for i, ent in enumerate(entries):
     if entries[idx][1] != ent[1]:
         idx = i
-    print 'MAKE_STATIC_ENT("{}", "{}", {}),'\
-        .format(ent[1], ent[2], entries[idx][0] - 1)
+    print 'MAKE_STATIC_ENT("{}", "{}", {}, {}u),'\
+        .format(ent[1], ent[2], entries[idx][0] - 1, hd_map_hash(ent[1]))
 print '};'