Remove metadata context entirely

8 files changed, 26 insertions, 52 deletions

diff --git a/src/core/transport/chttp2/hpack_encoder.c b/src/core/transport/chttp2/hpack_encoder.c
index 6c7c00b7c3..fe03b89dc2 100644
--- a/src/core/transport/chttp2/hpack_encoder.c
+++ b/src/core/transport/chttp2/hpack_encoder.c
@@ -42,6 +42,7 @@
 #include "src/core/transport/chttp2/hpack_table.h"
 #include "src/core/transport/chttp2/timeout_encoding.h"
 #include "src/core/transport/chttp2/varint.h"
+#include "src/core/transport/static_metadata.h"
 
 #define HASH_FRAGMENT_1(x) ((x)&255)
 #define HASH_FRAGMENT_2(x) ((x >> 8) & 255)
@@ -435,8 +436,7 @@ static void deadline_enc(grpc_chttp2_hpack_compressor *c, gpr_timespec deadline,
   grpc_chttp2_encode_timeout(
       gpr_time_sub(deadline, gpr_now(deadline.clock_type)), timeout_str);
   mdelem = grpc_mdelem_from_metadata_strings(
-      c->mdctx, GRPC_MDSTR_REF(c->timeout_key_str),
-      grpc_mdstr_from_string(c->mdctx, timeout_str));
+      GRPC_MDSTR_GRPC_TIMEOUT, grpc_mdstr_from_string(timeout_str));
   hpack_enc(c, mdelem, st);
   GRPC_MDELEM_UNREF(mdelem);
 }
@@ -447,11 +447,8 @@ gpr_slice grpc_chttp2_data_frame_create_empty_close(gpr_uint32 id) {
   return slice;
 }
 
-void grpc_chttp2_hpack_compressor_init(grpc_chttp2_hpack_compressor *c,
-                                       grpc_mdctx *ctx) {
+void grpc_chttp2_hpack_compressor_init(grpc_chttp2_hpack_compressor *c) {
   memset(c, 0, sizeof(*c));
-  c->mdctx = ctx;
-  c->timeout_key_str = grpc_mdstr_from_string(ctx, "grpc-timeout");
 }
 
 void grpc_chttp2_hpack_compressor_destroy(grpc_chttp2_hpack_compressor *c) {
@@ -460,7 +457,6 @@ void grpc_chttp2_hpack_compressor_destroy(grpc_chttp2_hpack_compressor *c) {
     if (c->entries_keys[i]) GRPC_MDSTR_UNREF(c->entries_keys[i]);
     if (c->entries_elems[i]) GRPC_MDELEM_UNREF(c->entries_elems[i]);
   }
-  GRPC_MDSTR_UNREF(c->timeout_key_str);
 }
 
 void grpc_chttp2_encode_header(grpc_chttp2_hpack_compressor *c,
diff --git a/src/core/transport/chttp2/hpack_encoder.h b/src/core/transport/chttp2/hpack_encoder.h
index 59b122dfda..dab6f66c71 100644
--- a/src/core/transport/chttp2/hpack_encoder.h
+++ b/src/core/transport/chttp2/hpack_encoder.h
@@ -59,11 +59,6 @@ typedef struct {
      been seen. When that count reaches max (255), all values are halved. */
   gpr_uint8 filter_elems[GRPC_CHTTP2_HPACKC_NUM_FILTERS];
 
-  /* metadata context */
-  grpc_mdctx *mdctx;
-  /* the string 'grpc-timeout' */
-  grpc_mdstr *timeout_key_str;
-
   /* entry tables for keys & elems: these tables track values that have been
      seen and *may* be in the decompressor table */
   grpc_mdstr *entries_keys[GRPC_CHTTP2_HPACKC_NUM_VALUES];
@@ -74,8 +69,7 @@ typedef struct {
   gpr_uint16 table_elem_size[GRPC_CHTTP2_HPACKC_MAX_TABLE_ELEMS];
 } grpc_chttp2_hpack_compressor;
 
-void grpc_chttp2_hpack_compressor_init(grpc_chttp2_hpack_compressor *c,
-                                       grpc_mdctx *mdctx);
+void grpc_chttp2_hpack_compressor_init(grpc_chttp2_hpack_compressor *c);
 void grpc_chttp2_hpack_compressor_destroy(grpc_chttp2_hpack_compressor *c);
 
 void grpc_chttp2_encode_header(grpc_chttp2_hpack_compressor *c, gpr_uint32 id,
diff --git a/src/core/transport/chttp2/hpack_parser.c b/src/core/transport/chttp2/hpack_parser.c
index 6eebfc3ce4..03a7d63b09 100644
--- a/src/core/transport/chttp2/hpack_parser.c
+++ b/src/core/transport/chttp2/hpack_parser.c
@@ -633,8 +633,7 @@ static void on_hdr(grpc_chttp2_hpack_parser *p, grpc_mdelem *md,
 
 static grpc_mdstr *take_string(grpc_chttp2_hpack_parser *p,
                                grpc_chttp2_hpack_parser_string *str) {
-  grpc_mdstr *s = grpc_mdstr_from_buffer(p->table.mdctx, (gpr_uint8 *)str->str,
-                                         str->length);
+  grpc_mdstr *s = grpc_mdstr_from_buffer((gpr_uint8 *)str->str, str->length);
   str->length = 0;
   return s;
 }
@@ -742,8 +741,7 @@ static int parse_indexed_field_x(grpc_chttp2_hpack_parser *p,
 static int finish_lithdr_incidx(grpc_chttp2_hpack_parser *p,
                                 const gpr_uint8 *cur, const gpr_uint8 *end) {
   grpc_mdelem *md = grpc_chttp2_hptbl_lookup(&p->table, p->index);
-  on_hdr(p, grpc_mdelem_from_metadata_strings(p->table.mdctx,
-                                              GRPC_MDSTR_REF(md->key),
+  on_hdr(p, grpc_mdelem_from_metadata_strings(GRPC_MDSTR_REF(md->key),
                                               take_string(p, &p->value)),
          1);
   return parse_begin(p, cur, end);
@@ -752,8 +750,7 @@ static int finish_lithdr_incidx(grpc_chttp2_hpack_parser *p,
 /* finish a literal header with incremental indexing with no index */
 static int finish_lithdr_incidx_v(grpc_chttp2_hpack_parser *p,
                                   const gpr_uint8 *cur, const gpr_uint8 *end) {
-  on_hdr(p, grpc_mdelem_from_metadata_strings(p->table.mdctx,
-                                              take_string(p, &p->key),
+  on_hdr(p, grpc_mdelem_from_metadata_strings(take_string(p, &p->key),
                                               take_string(p, &p->value)),
          1);
   return parse_begin(p, cur, end);
@@ -795,8 +792,7 @@ static int parse_lithdr_incidx_v(grpc_chttp2_hpack_parser *p,
 static int finish_lithdr_notidx(grpc_chttp2_hpack_parser *p,
                                 const gpr_uint8 *cur, const gpr_uint8 *end) {
   grpc_mdelem *md = grpc_chttp2_hptbl_lookup(&p->table, p->index);
-  on_hdr(p, grpc_mdelem_from_metadata_strings(p->table.mdctx,
-                                              GRPC_MDSTR_REF(md->key),
+  on_hdr(p, grpc_mdelem_from_metadata_strings(GRPC_MDSTR_REF(md->key),
                                               take_string(p, &p->value)),
          0);
   return parse_begin(p, cur, end);
@@ -805,8 +801,7 @@ static int finish_lithdr_notidx(grpc_chttp2_hpack_parser *p,
 /* finish a literal header without incremental indexing with index = 0 */
 static int finish_lithdr_notidx_v(grpc_chttp2_hpack_parser *p,
                                   const gpr_uint8 *cur, const gpr_uint8 *end) {
-  on_hdr(p, grpc_mdelem_from_metadata_strings(p->table.mdctx,
-                                              take_string(p, &p->key),
+  on_hdr(p, grpc_mdelem_from_metadata_strings(take_string(p, &p->key),
                                               take_string(p, &p->value)),
          0);
   return parse_begin(p, cur, end);
@@ -848,8 +843,7 @@ static int parse_lithdr_notidx_v(grpc_chttp2_hpack_parser *p,
 static int finish_lithdr_nvridx(grpc_chttp2_hpack_parser *p,
                                 const gpr_uint8 *cur, const gpr_uint8 *end) {
   grpc_mdelem *md = grpc_chttp2_hptbl_lookup(&p->table, p->index);
-  on_hdr(p, grpc_mdelem_from_metadata_strings(p->table.mdctx,
-                                              GRPC_MDSTR_REF(md->key),
+  on_hdr(p, grpc_mdelem_from_metadata_strings(GRPC_MDSTR_REF(md->key),
                                               take_string(p, &p->value)),
          0);
   return parse_begin(p, cur, end);
@@ -858,8 +852,7 @@ static int finish_lithdr_nvridx(grpc_chttp2_hpack_parser *p,
 /* finish a literal header that is never indexed with an extra value */
 static int finish_lithdr_nvridx_v(grpc_chttp2_hpack_parser *p,
                                   const gpr_uint8 *cur, const gpr_uint8 *end) {
-  on_hdr(p, grpc_mdelem_from_metadata_strings(p->table.mdctx,
-                                              take_string(p, &p->key),
+  on_hdr(p, grpc_mdelem_from_metadata_strings(take_string(p, &p->key),
                                               take_string(p, &p->value)),
          0);
   return parse_begin(p, cur, end);
@@ -1342,8 +1335,7 @@ static void on_header_not_set(void *user_data, grpc_mdelem *md) {
   abort();
 }
 
-void grpc_chttp2_hpack_parser_init(grpc_chttp2_hpack_parser *p,
-                                   grpc_mdctx *mdctx) {
+void grpc_chttp2_hpack_parser_init(grpc_chttp2_hpack_parser *p) {
   p->on_header = on_header_not_set;
   p->on_header_user_data = NULL;
   p->state = parse_begin;
@@ -1353,7 +1345,7 @@ void grpc_chttp2_hpack_parser_init(grpc_chttp2_hpack_parser *p,
   p->value.str = NULL;
   p->value.capacity = 0;
   p->value.length = 0;
-  grpc_chttp2_hptbl_init(&p->table, mdctx);
+  grpc_chttp2_hptbl_init(&p->table);
 }
 
 void grpc_chttp2_hpack_parser_set_has_priority(grpc_chttp2_hpack_parser *p) {
diff --git a/src/core/transport/chttp2/hpack_parser.h b/src/core/transport/chttp2/hpack_parser.h
index f56867016c..fb894b5735 100644
--- a/src/core/transport/chttp2/hpack_parser.h
+++ b/src/core/transport/chttp2/hpack_parser.h
@@ -95,8 +95,7 @@ struct grpc_chttp2_hpack_parser {
   grpc_chttp2_hptbl table;
 };
 
-void grpc_chttp2_hpack_parser_init(grpc_chttp2_hpack_parser *p,
-                                   grpc_mdctx *mdctx);
+void grpc_chttp2_hpack_parser_init(grpc_chttp2_hpack_parser *p);
 void grpc_chttp2_hpack_parser_destroy(grpc_chttp2_hpack_parser *p);
 
 void grpc_chttp2_hpack_parser_set_has_priority(grpc_chttp2_hpack_parser *p);
diff --git a/src/core/transport/chttp2/hpack_table.c b/src/core/transport/chttp2/hpack_table.c
index c442c2c341..f66745f069 100644
--- a/src/core/transport/chttp2/hpack_table.c
+++ b/src/core/transport/chttp2/hpack_table.c
@@ -169,15 +169,14 @@ static struct {
     {"www-authenticate", ""},
 };
 
-void grpc_chttp2_hptbl_init(grpc_chttp2_hptbl *tbl, grpc_mdctx *mdctx) {
+void grpc_chttp2_hptbl_init(grpc_chttp2_hptbl *tbl) {
   size_t i;
 
   memset(tbl, 0, sizeof(*tbl));
-  tbl->mdctx = mdctx;
   tbl->max_bytes = GRPC_CHTTP2_INITIAL_HPACK_TABLE_SIZE;
   for (i = 1; i <= GRPC_CHTTP2_LAST_STATIC_ENTRY; i++) {
-    tbl->static_ents[i - 1] = grpc_mdelem_from_strings(
-        mdctx, static_table[i].key, static_table[i].value);
+    tbl->static_ents[i - 1] =
+        grpc_mdelem_from_strings(static_table[i].key, static_table[i].value);
   }
 }
 
diff --git a/src/core/transport/chttp2/hpack_table.h b/src/core/transport/chttp2/hpack_table.h
index 4f882e2e03..d2587e0758 100644
--- a/src/core/transport/chttp2/hpack_table.h
+++ b/src/core/transport/chttp2/hpack_table.h
@@ -57,7 +57,6 @@
 
 /* hpack decoder table */
 typedef struct {
-  grpc_mdctx *mdctx;
   /* the first used entry in ents */
   gpr_uint16 first_ent;
   /* the last used entry in ents */
@@ -77,7 +76,7 @@ typedef struct {
 } grpc_chttp2_hptbl;
 
 /* initialize a hpack table */
-void grpc_chttp2_hptbl_init(grpc_chttp2_hptbl *tbl, grpc_mdctx *mdctx);
+void grpc_chttp2_hptbl_init(grpc_chttp2_hptbl *tbl);
 void grpc_chttp2_hptbl_destroy(grpc_chttp2_hptbl *tbl);
 
 /* lookup a table entry based on its hpack index */
diff --git a/src/core/transport/chttp2/internal.h b/src/core/transport/chttp2/internal.h
index 2d0cb4abdb..99b5187d46 100644
--- a/src/core/transport/chttp2/internal.h
+++ b/src/core/transport/chttp2/internal.h
@@ -232,9 +232,6 @@ struct grpc_chttp2_transport_parsing {
 
   /** data to write later - after parsing */
   gpr_slice_buffer qbuf;
-  /* metadata object cache */
-  grpc_mdstr *str_grpc_timeout;
-  grpc_mdelem *elem_grpc_status_ok;
   /** parser for headers */
   grpc_chttp2_hpack_parser hpack_parser;
   /** simple one shot parsers */
@@ -288,7 +285,6 @@ struct grpc_chttp2_transport_parsing {
 struct grpc_chttp2_transport {
   grpc_transport base; /* must be first */
   grpc_endpoint *ep;
-  grpc_mdctx *metadata_context;
   gpr_refcount refs;
   char *peer_string;
 
diff --git a/src/core/transport/chttp2/parsing.c b/src/core/transport/chttp2/parsing.c
index 8cef8fbb77..2872a3a5c1 100644
--- a/src/core/transport/chttp2/parsing.c
+++ b/src/core/transport/chttp2/parsing.c
@@ -35,14 +35,15 @@
 
 #include <string.h>
 
+#include <grpc/support/alloc.h>
+#include <grpc/support/log.h>
+#include <grpc/support/string_util.h>
+
 #include "src/core/profiling/timers.h"
 #include "src/core/transport/chttp2/http2_errors.h"
 #include "src/core/transport/chttp2/status_conversion.h"
 #include "src/core/transport/chttp2/timeout_encoding.h"
-
-#include <grpc/support/alloc.h>
-#include <grpc/support/log.h>
-#include <grpc/support/string_util.h>
+#include "src/core/transport/static_metadata.h"
 
 static int init_frame_parser(grpc_exec_ctx *exec_ctx,
                              grpc_chttp2_transport_parsing *transport_parsing);
@@ -588,13 +589,12 @@ static void on_initial_header(void *tp, grpc_mdelem *md) {
       transport_parsing->is_client ? "CLI" : "SVR",
       grpc_mdstr_as_c_string(md->key), grpc_mdstr_as_c_string(md->value)));
 
-  if (md->key == transport_parsing->elem_grpc_status_ok->key &&
-      md != transport_parsing->elem_grpc_status_ok) {
+  if (md->key == GRPC_MDSTR_GRPC_STATUS && md != GRPC_MDELEM_GRPC_STATUS_0) {
     /* TODO(ctiller): check for a status like " 0" */
     stream_parsing->seen_error = 1;
   }
 
-  if (md->key == transport_parsing->str_grpc_timeout) {
+  if (md->key == GRPC_MDSTR_GRPC_TIMEOUT) {
     gpr_timespec *cached_timeout = grpc_mdelem_get_user_data(md, free_timeout);
     if (!cached_timeout) {
       /* not already parsed: parse it now, and store the result away */
@@ -635,8 +635,7 @@ static void on_trailing_header(void *tp, grpc_mdelem *md) {
       transport_parsing->is_client ? "CLI" : "SVR",
       grpc_mdstr_as_c_string(md->key), grpc_mdstr_as_c_string(md->value)));
 
-  if (md->key == transport_parsing->elem_grpc_status_ok->key &&
-      md != transport_parsing->elem_grpc_status_ok) {
+  if (md->key == GRPC_MDSTR_GRPC_STATUS && md != GRPC_MDELEM_GRPC_STATUS_0) {
     /* TODO(ctiller): check for a status like " 0" */
     stream_parsing->seen_error = 1;
   }