/* encode an mdelem */
static void hpack_enc(grpc_chttp2_hpack_compressor *c, grpc_mdelem *elem,
framer_state *st) {
uint32_t key_hash = elem->key->hash;
uint32_t elem_hash = GRPC_MDSTR_KV_HASH(key_hash, elem->value->hash);
size_t decoder_space_usage;
uint32_t indices_key;
int should_add_elem;
GPR_ASSERT(GPR_SLICE_LENGTH(elem->key->slice) > 0);
if (GPR_SLICE_START_PTR(elem->key->slice)[0] != ':') { /* regular header */
st->seen_regular_header = 1;
} else {
GPR_ASSERT(
st->seen_regular_header == 0 &&
"Reserved header (colon-prefixed) happening after regular ones.");
}
inc_filter(HASH_FRAGMENT_1(elem_hash), &c->filter_elems_sum, c->filter_elems);
/* is this elem currently in the decoders table? */
if (c->entries_elems[HASH_FRAGMENT_2(elem_hash)] == elem &&
c->indices_elems[HASH_FRAGMENT_2(elem_hash)] > c->tail_remote_index) {
/* HIT: complete element (first cuckoo hash) */
emit_indexed(c, dynidx(c, c->indices_elems[HASH_FRAGMENT_2(elem_hash)]),
st);
return;
}
if (c->entries_elems[HASH_FRAGMENT_3(elem_hash)] == elem &&
c->indices_elems[HASH_FRAGMENT_3(elem_hash)] > c->tail_remote_index) {
/* HIT: complete element (second cuckoo hash) */
emit_indexed(c, dynidx(c, c->indices_elems[HASH_FRAGMENT_3(elem_hash)]),
st);
return;
}
/* should this elem be in the table? */
decoder_space_usage = grpc_mdelem_get_size_in_hpack_table(elem);
should_add_elem = decoder_space_usage < MAX_DECODER_SPACE_USAGE &&
c->filter_elems[HASH_FRAGMENT_1(elem_hash)] >=
c->filter_elems_sum / ONE_ON_ADD_PROBABILITY;
/* no hits for the elem... maybe there's a key? */
indices_key = c->indices_keys[HASH_FRAGMENT_2(key_hash)];
if (c->entries_keys[HASH_FRAGMENT_2(key_hash)] == elem->key &&
indices_key > c->tail_remote_index) {
/* HIT: key (first cuckoo hash) */
if (should_add_elem) {
emit_lithdr_incidx(c, dynidx(c, indices_key), elem, st);
add_elem(c, elem);
return;
} else {
emit_lithdr_noidx(c, dynidx(c, indices_key), elem, st);
return;
}
GPR_UNREACHABLE_CODE(return );
}
indices_key = c->indices_keys[HASH_FRAGMENT_3(key_hash)];
if (c->entries_keys[HASH_FRAGMENT_3(key_hash)] == elem->key &&
indices_key > c->tail_remote_index) {
/* HIT: key (first cuckoo hash) */
if (should_add_elem) {
emit_lithdr_incidx(c, dynidx(c, indices_key), elem, st);
add_elem(c, elem);
return;
} else {
emit_lithdr_noidx(c, dynidx(c, indices_key), elem, st);
return;
}
GPR_UNREACHABLE_CODE(return );
}
/* no elem, key in the table... fall back to literal emission */
if (should_add_elem) {
emit_lithdr_incidx_v(c, elem, st);
add_elem(c, elem);
return;
} else {
emit_lithdr_noidx_v(c, elem, st);
return;
}
GPR_UNREACHABLE_CODE(return );
}
/* encode an mdelem */
static void hpack_enc(grpc_exec_ctx *exec_ctx, grpc_chttp2_hpack_compressor *c,
grpc_mdelem elem, framer_state *st) {
GPR_ASSERT(GRPC_SLICE_LENGTH(GRPC_MDKEY(elem)) > 0);
if (GRPC_SLICE_START_PTR(GRPC_MDKEY(elem))[0] != ':') { /* regular header */
st->seen_regular_header = 1;
} else {
GPR_ASSERT(
st->seen_regular_header == 0 &&
"Reserved header (colon-prefixed) happening after regular ones.");
}
if (grpc_http_trace && !GRPC_MDELEM_IS_INTERNED(elem)) {
char *k = grpc_slice_to_c_string(GRPC_MDKEY(elem));
char *v = grpc_slice_to_c_string(GRPC_MDVALUE(elem));
gpr_log(
GPR_DEBUG,
"Encode: '%s: %s', elem_interned=%d [%d], k_interned=%d, v_interned=%d",
k, v, GRPC_MDELEM_IS_INTERNED(elem), GRPC_MDELEM_STORAGE(elem),
grpc_slice_is_interned(GRPC_MDKEY(elem)),
grpc_slice_is_interned(GRPC_MDVALUE(elem)));
gpr_free(k);
gpr_free(v);
}
if (!GRPC_MDELEM_IS_INTERNED(elem)) {
emit_lithdr_noidx_v(c, elem, st);
return;
}
uint32_t key_hash;
uint32_t value_hash;
uint32_t elem_hash;
size_t decoder_space_usage;
uint32_t indices_key;
int should_add_elem;
key_hash = grpc_slice_hash(GRPC_MDKEY(elem));
value_hash = grpc_slice_hash(GRPC_MDVALUE(elem));
elem_hash = GRPC_MDSTR_KV_HASH(key_hash, value_hash);
inc_filter(HASH_FRAGMENT_1(elem_hash), &c->filter_elems_sum, c->filter_elems);
/* is this elem currently in the decoders table? */
if (grpc_mdelem_eq(c->entries_elems[HASH_FRAGMENT_2(elem_hash)], elem) &&
c->indices_elems[HASH_FRAGMENT_2(elem_hash)] > c->tail_remote_index) {
/* HIT: complete element (first cuckoo hash) */
emit_indexed(c, dynidx(c, c->indices_elems[HASH_FRAGMENT_2(elem_hash)]),
st);
return;
}
if (grpc_mdelem_eq(c->entries_elems[HASH_FRAGMENT_3(elem_hash)], elem) &&
c->indices_elems[HASH_FRAGMENT_3(elem_hash)] > c->tail_remote_index) {
/* HIT: complete element (second cuckoo hash) */
emit_indexed(c, dynidx(c, c->indices_elems[HASH_FRAGMENT_3(elem_hash)]),
st);
return;
}
/* should this elem be in the table? */
decoder_space_usage = grpc_mdelem_get_size_in_hpack_table(elem);
should_add_elem = decoder_space_usage < MAX_DECODER_SPACE_USAGE &&
c->filter_elems[HASH_FRAGMENT_1(elem_hash)] >=
c->filter_elems_sum / ONE_ON_ADD_PROBABILITY;
/* no hits for the elem... maybe there's a key? */
indices_key = c->indices_keys[HASH_FRAGMENT_2(key_hash)];
if (grpc_slice_eq(c->entries_keys[HASH_FRAGMENT_2(key_hash)],
GRPC_MDKEY(elem)) &&
indices_key > c->tail_remote_index) {
/* HIT: key (first cuckoo hash) */
if (should_add_elem) {
emit_lithdr_incidx(c, dynidx(c, indices_key), elem, st);
add_elem(exec_ctx, c, elem);
return;
} else {
emit_lithdr_noidx(c, dynidx(c, indices_key), elem, st);
return;
}
GPR_UNREACHABLE_CODE(return );
}
indices_key = c->indices_keys[HASH_FRAGMENT_3(key_hash)];
if (grpc_slice_eq(c->entries_keys[HASH_FRAGMENT_3(key_hash)],
GRPC_MDKEY(elem)) &&
indices_key > c->tail_remote_index) {
/* HIT: key (first cuckoo hash) */
if (should_add_elem) {
emit_lithdr_incidx(c, dynidx(c, indices_key), elem, st);
add_elem(exec_ctx, c, elem);
return;
} else {
emit_lithdr_noidx(c, dynidx(c, indices_key), elem, st);
return;
}
GPR_UNREACHABLE_CODE(return );
}
/* no elem, key in the table... fall back to literal emission */
if (should_add_elem) {
emit_lithdr_incidx_v(c, elem, st);
add_elem(exec_ctx, c, elem);
return;
} else {
emit_lithdr_noidx_v(c, elem, st);
return;
}
GPR_UNREACHABLE_CODE(return );
}
/* add an element to the decoder table */
static void add_elem(grpc_chttp2_hpack_compressor *c, grpc_mdelem *elem) {
uint32_t key_hash = elem->key->hash;
uint32_t elem_hash = GRPC_MDSTR_KV_HASH(key_hash, elem->value->hash);
uint32_t new_index = c->tail_remote_index + c->table_elems + 1;
size_t elem_size = grpc_mdelem_get_size_in_hpack_table(elem);
GPR_ASSERT(elem_size < 65536);
if (elem_size > c->max_table_size) {
while (c->table_size > 0) {
evict_entry(c);
}
return;
}
/* Reserve space for this element in the remote table: if this overflows
the current table, drop elements until it fits, matching the decompressor
algorithm */
while (c->table_size + elem_size > c->max_table_size) {
evict_entry(c);
}
GPR_ASSERT(c->table_elems < c->max_table_size);
c->table_elem_size[new_index % c->cap_table_elems] = (uint16_t)elem_size;
c->table_size = (uint16_t)(c->table_size + elem_size);
c->table_elems++;
/* Store this element into {entries,indices}_elem */
if (c->entries_elems[HASH_FRAGMENT_2(elem_hash)] == elem) {
/* already there: update with new index */
c->indices_elems[HASH_FRAGMENT_2(elem_hash)] = new_index;
} else if (c->entries_elems[HASH_FRAGMENT_3(elem_hash)] == elem) {
/* already there (cuckoo): update with new index */
c->indices_elems[HASH_FRAGMENT_3(elem_hash)] = new_index;
} else if (c->entries_elems[HASH_FRAGMENT_2(elem_hash)] == NULL) {
/* not there, but a free element: add */
c->entries_elems[HASH_FRAGMENT_2(elem_hash)] = GRPC_MDELEM_REF(elem);
c->indices_elems[HASH_FRAGMENT_2(elem_hash)] = new_index;
} else if (c->entries_elems[HASH_FRAGMENT_3(elem_hash)] == NULL) {
/* not there (cuckoo), but a free element: add */
c->entries_elems[HASH_FRAGMENT_3(elem_hash)] = GRPC_MDELEM_REF(elem);
c->indices_elems[HASH_FRAGMENT_3(elem_hash)] = new_index;
} else if (c->indices_elems[HASH_FRAGMENT_2(elem_hash)] <
c->indices_elems[HASH_FRAGMENT_3(elem_hash)]) {
/* not there: replace oldest */
GRPC_MDELEM_UNREF(c->entries_elems[HASH_FRAGMENT_2(elem_hash)]);
c->entries_elems[HASH_FRAGMENT_2(elem_hash)] = GRPC_MDELEM_REF(elem);
c->indices_elems[HASH_FRAGMENT_2(elem_hash)] = new_index;
} else {
/* not there: replace oldest */
GRPC_MDELEM_UNREF(c->entries_elems[HASH_FRAGMENT_3(elem_hash)]);
c->entries_elems[HASH_FRAGMENT_3(elem_hash)] = GRPC_MDELEM_REF(elem);
c->indices_elems[HASH_FRAGMENT_3(elem_hash)] = new_index;
}
/* do exactly the same for the key (so we can find by that again too) */
if (c->entries_keys[HASH_FRAGMENT_2(key_hash)] == elem->key) {
c->indices_keys[HASH_FRAGMENT_2(key_hash)] = new_index;
} else if (c->entries_keys[HASH_FRAGMENT_3(key_hash)] == elem->key) {
c->indices_keys[HASH_FRAGMENT_3(key_hash)] = new_index;
} else if (c->entries_keys[HASH_FRAGMENT_2(key_hash)] == NULL) {
c->entries_keys[HASH_FRAGMENT_2(key_hash)] = GRPC_MDSTR_REF(elem->key);
c->indices_keys[HASH_FRAGMENT_2(key_hash)] = new_index;
} else if (c->entries_keys[HASH_FRAGMENT_3(key_hash)] == NULL) {
c->entries_keys[HASH_FRAGMENT_3(key_hash)] = GRPC_MDSTR_REF(elem->key);
c->indices_keys[HASH_FRAGMENT_3(key_hash)] = new_index;
} else if (c->indices_keys[HASH_FRAGMENT_2(key_hash)] <
c->indices_keys[HASH_FRAGMENT_3(key_hash)]) {
GRPC_MDSTR_UNREF(c->entries_keys[HASH_FRAGMENT_2(key_hash)]);
c->entries_keys[HASH_FRAGMENT_2(key_hash)] = GRPC_MDSTR_REF(elem->key);
c->indices_keys[HASH_FRAGMENT_2(key_hash)] = new_index;
} else {
GRPC_MDSTR_UNREF(c->entries_keys[HASH_FRAGMENT_3(key_hash)]);
c->entries_keys[HASH_FRAGMENT_3(key_hash)] = GRPC_MDSTR_REF(elem->key);
c->indices_keys[HASH_FRAGMENT_3(key_hash)] = new_index;
}
}
/* add an element to the decoder table */
static void add_elem(grpc_exec_ctx *exec_ctx, grpc_chttp2_hpack_compressor *c,
grpc_mdelem elem) {
GPR_ASSERT(GRPC_MDELEM_IS_INTERNED(elem));
uint32_t key_hash = grpc_slice_hash(GRPC_MDKEY(elem));
uint32_t value_hash = grpc_slice_hash(GRPC_MDVALUE(elem));
uint32_t elem_hash = GRPC_MDSTR_KV_HASH(key_hash, value_hash);
uint32_t new_index = c->tail_remote_index + c->table_elems + 1;
size_t elem_size = grpc_mdelem_get_size_in_hpack_table(elem);
GPR_ASSERT(elem_size < 65536);
if (elem_size > c->max_table_size) {
while (c->table_size > 0) {
evict_entry(c);
}
return;
}
/* Reserve space for this element in the remote table: if this overflows
the current table, drop elements until it fits, matching the decompressor
algorithm */
while (c->table_size + elem_size > c->max_table_size) {
evict_entry(c);
}
GPR_ASSERT(c->table_elems < c->max_table_size);
c->table_elem_size[new_index % c->cap_table_elems] = (uint16_t)elem_size;
c->table_size = (uint16_t)(c->table_size + elem_size);
c->table_elems++;
/* Store this element into {entries,indices}_elem */
if (grpc_mdelem_eq(c->entries_elems[HASH_FRAGMENT_2(elem_hash)], elem)) {
/* already there: update with new index */
c->indices_elems[HASH_FRAGMENT_2(elem_hash)] = new_index;
} else if (grpc_mdelem_eq(c->entries_elems[HASH_FRAGMENT_3(elem_hash)],
elem)) {
/* already there (cuckoo): update with new index */
c->indices_elems[HASH_FRAGMENT_3(elem_hash)] = new_index;
} else if (GRPC_MDISNULL(c->entries_elems[HASH_FRAGMENT_2(elem_hash)])) {
/* not there, but a free element: add */
c->entries_elems[HASH_FRAGMENT_2(elem_hash)] = GRPC_MDELEM_REF(elem);
c->indices_elems[HASH_FRAGMENT_2(elem_hash)] = new_index;
} else if (GRPC_MDISNULL(c->entries_elems[HASH_FRAGMENT_3(elem_hash)])) {
/* not there (cuckoo), but a free element: add */
c->entries_elems[HASH_FRAGMENT_3(elem_hash)] = GRPC_MDELEM_REF(elem);
c->indices_elems[HASH_FRAGMENT_3(elem_hash)] = new_index;
} else if (c->indices_elems[HASH_FRAGMENT_2(elem_hash)] <
c->indices_elems[HASH_FRAGMENT_3(elem_hash)]) {
/* not there: replace oldest */
GRPC_MDELEM_UNREF(exec_ctx, c->entries_elems[HASH_FRAGMENT_2(elem_hash)]);
c->entries_elems[HASH_FRAGMENT_2(elem_hash)] = GRPC_MDELEM_REF(elem);
c->indices_elems[HASH_FRAGMENT_2(elem_hash)] = new_index;
} else {
/* not there: replace oldest */
GRPC_MDELEM_UNREF(exec_ctx, c->entries_elems[HASH_FRAGMENT_3(elem_hash)]);
c->entries_elems[HASH_FRAGMENT_3(elem_hash)] = GRPC_MDELEM_REF(elem);
c->indices_elems[HASH_FRAGMENT_3(elem_hash)] = new_index;
}
/* do exactly the same for the key (so we can find by that again too) */
if (grpc_slice_eq(c->entries_keys[HASH_FRAGMENT_2(key_hash)],
GRPC_MDKEY(elem))) {
c->indices_keys[HASH_FRAGMENT_2(key_hash)] = new_index;
} else if (grpc_slice_eq(c->entries_keys[HASH_FRAGMENT_3(key_hash)],
GRPC_MDKEY(elem))) {
c->indices_keys[HASH_FRAGMENT_3(key_hash)] = new_index;
} else if (c->entries_keys[HASH_FRAGMENT_2(key_hash)].refcount ==
&terminal_slice_refcount) {
c->entries_keys[HASH_FRAGMENT_2(key_hash)] =
grpc_slice_ref_internal(GRPC_MDKEY(elem));
c->indices_keys[HASH_FRAGMENT_2(key_hash)] = new_index;
} else if (c->entries_keys[HASH_FRAGMENT_3(key_hash)].refcount ==
&terminal_slice_refcount) {
c->entries_keys[HASH_FRAGMENT_3(key_hash)] =
grpc_slice_ref_internal(GRPC_MDKEY(elem));
c->indices_keys[HASH_FRAGMENT_3(key_hash)] = new_index;
} else if (c->indices_keys[HASH_FRAGMENT_2(key_hash)] <
c->indices_keys[HASH_FRAGMENT_3(key_hash)]) {
grpc_slice_unref_internal(exec_ctx,
c->entries_keys[HASH_FRAGMENT_2(key_hash)]);
c->entries_keys[HASH_FRAGMENT_2(key_hash)] =
grpc_slice_ref_internal(GRPC_MDKEY(elem));
c->indices_keys[HASH_FRAGMENT_2(key_hash)] = new_index;
} else {
grpc_slice_unref_internal(exec_ctx,
c->entries_keys[HASH_FRAGMENT_3(key_hash)]);
c->entries_keys[HASH_FRAGMENT_3(key_hash)] =
grpc_slice_ref_internal(GRPC_MDKEY(elem));
c->indices_keys[HASH_FRAGMENT_3(key_hash)] = new_index;
}
}
