nghttp2_hd: Use defalte_hd_table_bufsize for decoder as well

lib/nghttp2_hd.c

@@ -708,12 +708,12 @@ static nghttp2_hd_entry* add_hd_table_incremental(nghttp2_hd_context *context,
     size_t index = context->hd_table.len - 1;
     nghttp2_hd_entry* ent = nghttp2_hd_ringbuf_get(&context->hd_table, index);
     context->hd_table_bufsize -= entry_room(ent->nv.namelen, ent->nv.valuelen);
-    if(context->role == NGHTTP2_HD_ROLE_DEFLATE) {
     if(context->hd_table_bufsize < context->deflate_hd_table_bufsize) {
       context->deflate_hd_table_bufsize -= entry_room(ent->nv.namelen,
                                                       ent->nv.valuelen);
       --context->deflate_hd_tablelen;
     }
+    if(context->role == NGHTTP2_HD_ROLE_DEFLATE) {
       if(ent->flags & NGHTTP2_HD_FLAG_IMPLICIT_EMIT) {
         /* Emit common header just before it slips away from the
            table. If we don't do this, we have to emit it in literal
@@ -730,7 +730,6 @@ static nghttp2_hd_entry* add_hd_table_incremental(nghttp2_hd_context *context,
       free(ent);
     }
   }
-  if(context->role == NGHTTP2_HD_ROLE_DEFLATE) {
   while(context->deflate_hd_table_bufsize + room >
         context->deflate_hd_table_bufsize_max
         && context->deflate_hd_tablelen > 0) {
@@ -770,7 +769,6 @@ static nghttp2_hd_entry* add_hd_table_incremental(nghttp2_hd_context *context,
       ent->flags ^= NGHTTP2_HD_FLAG_VALUE_ALLOC;
     }
   }
-  }
 
   new_ent = malloc(sizeof(nghttp2_hd_entry));
   if(new_ent == NULL) {
@@ -816,8 +814,7 @@ static nghttp2_hd_entry* add_hd_table_incremental(nghttp2_hd_context *context,
     context->hd_table_bufsize += room;
     new_ent->flags |= NGHTTP2_HD_FLAG_REFSET;
     nghttp2_hd_ringbuf_push_front(&context->hd_table, new_ent);
-    if(context->role == NGHTTP2_HD_ROLE_DEFLATE &&
-       room <= context->deflate_hd_table_bufsize_max) {
+    if(room <= context->deflate_hd_table_bufsize_max) {
       context->deflate_hd_table_bufsize += room;
       ++context->deflate_hd_tablelen;
     }
@@ -828,9 +825,7 @@ static nghttp2_hd_entry* add_hd_table_incremental(nghttp2_hd_context *context,
 static ssize_t find_in_hd_table(nghttp2_hd_context *context, nghttp2_nv *nv)
 {
   size_t i;
-  size_t max = context->role == NGHTTP2_HD_ROLE_DEFLATE ?
-    context->deflate_hd_tablelen : context->hd_table.len;
-  for(i = 0; i < max; ++i) {
+  for(i = 0; i < context->deflate_hd_tablelen; ++i) {
     nghttp2_hd_entry *ent = nghttp2_hd_ringbuf_get(&context->hd_table, i);
     if(nghttp2_nv_equal(&ent->nv, nv)) {
       return i;
@@ -849,9 +844,7 @@ static ssize_t find_name_in_hd_table(nghttp2_hd_context *context,
                                      nghttp2_nv *nv)
 {
   size_t i;
-  size_t max = context->role == NGHTTP2_HD_ROLE_DEFLATE ?
-    context->deflate_hd_tablelen : context->hd_table.len;
-  for(i = 0; i < max; ++i) {
+  for(i = 0; i < context->deflate_hd_tablelen; ++i) {
     nghttp2_hd_entry *ent = nghttp2_hd_ringbuf_get(&context->hd_table, i);
     if(ent->nv.namelen == nv->namelen &&
        memcmp(ent->nv.name, nv->name, nv->namelen) == 0) {
@@ -878,18 +871,19 @@ int nghttp2_hd_change_table_size(nghttp2_hd_context *context,
     return rv;
   }
   context->hd_table_bufsize_max = hd_table_bufsize_max;
+  if(context->role == NGHTTP2_HD_ROLE_INFLATE) {
+    context->deflate_hd_table_bufsize_max = hd_table_bufsize_max;
+  }
   while(context->hd_table_bufsize > context->hd_table_bufsize_max &&
         context->hd_table.len > 0) {
     size_t index = context->hd_table.len - 1;
     nghttp2_hd_entry* ent = nghttp2_hd_ringbuf_get(&context->hd_table, index);
     context->hd_table_bufsize -= entry_room(ent->nv.namelen, ent->nv.valuelen);
-    if(context->role == NGHTTP2_HD_ROLE_DEFLATE) {
     if(context->hd_table_bufsize < context->deflate_hd_table_bufsize) {
       context->deflate_hd_table_bufsize -= entry_room(ent->nv.namelen,
                                                       ent->nv.valuelen);
       --context->deflate_hd_tablelen;
     }
-    }
     nghttp2_hd_ringbuf_pop_back(&context->hd_table);
     if(--ent->ref == 0) {
       nghttp2_hd_entry_free(ent);

lib/nghttp2_hd.h

@@ -93,18 +93,22 @@ typedef struct {
   /* The header table size for decoding. If the context is initialized
      as encoder, this value is advertised by remote endpoint
      decoder. */
+  size_t hd_table_bufsize;
+  /* If inflate/deflate error occurred, this value is set to 1 and
+     further invocation of inflate/deflate will fail with
+     NGHTTP2_ERR_HEADER_COMP. */
   size_t hd_table_bufsize_max;
   /* The current effective header table size for encoding. This value
-     is meaningful iff this context is initialized as
-     encoder. |deflate_hd_table_bufsize| <= |hd_table_bufsize| must be
+     is always equal to |hd_table_bufsize| on decoder
+     context. |deflate_hd_table_bufsize| <= |hd_table_bufsize| must be
      hold. */
   size_t deflate_hd_table_bufsize;
   /* The maximum effective header table for encoding. Although header
      table size is bounded by |hd_table_bufsize_max|, the encoder can
      use smaller buffer by not retaining the header name/values beyond
      the |deflate_hd_table_bufsize_max| and not referencing those
-     entries. This value is meaningful iff this context is initialized
-     as encoder. */
+     entries. This value is always equal to |hd_table_bufsize_max| on
+     decoder context. */
   size_t deflate_hd_table_bufsize_max;
   /* The number of effective entry in |hd_table|. */
   size_t deflate_hd_tablelen;
@@ -118,10 +122,6 @@ typedef struct {
   /* Abstract buffer size of hd_table as described in the spec. This
      is the sum of length of name/value in hd_table +
      NGHTTP2_HD_ENTRY_OVERHEAD bytes overhead per each entry. */
-  size_t hd_table_bufsize;
-  /* 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;
   /* Role of this context; deflate or infalte */
   nghttp2_hd_role role;