Mass API rename and clang-reformat (#485)

* Wave 1: upb_fielddef.

* upb_fielddef itself.

* upb_oneofdef.

* upb_msgdef.

* ExtensionRange.

* upb_enumdef

* upb_enumvaldef

* upb_filedef

* upb_methoddef

* upb_servicedef

* upb_symtab

* upb_defpool_init

* upb_wellknown and upb_syntax_t

* Some constants.

* upb_status

* upb_strview

* upb_arena

* upb.h constants

* reflection

* encode

* JSON decode.

* json encode.

* msg_internal.

* Formatted with clang-format.

* Some naming fixups and comment reformatting.

* More refinements.

* A few more stragglers.

* Fixed PyObject_HEAD with semicolon. Removed TODO entries.
diff --git a/upb/json_encode.c b/upb/json_encode.c
index d7bebc2..5745fda 100644
--- a/upb/json_encode.c
+++ b/upb/json_encode.c
@@ -13,11 +13,11 @@
  *       names of its contributors may be used to endorse or promote products
  *       derived from this software without specific prior written permission.
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
- * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
- * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
- * DISCLAIMED. IN NO EVENT SHALL Google LLC BE LIABLE FOR ANY
- * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL Google LLC BE LIABLE FOR ANY DIRECT,
+ * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
@@ -47,43 +47,46 @@
   size_t overflow;
   int indent_depth;
   int options;
-  const upb_symtab *ext_pool;
+  const upb_DefPool* ext_pool;
   jmp_buf err;
-  upb_status *status;
-  upb_arena *arena;
+  upb_Status* status;
+  upb_Arena* arena;
 } jsonenc;
 
-static void jsonenc_msg(jsonenc *e, const upb_msg *msg, const upb_msgdef *m);
-static void jsonenc_scalar(jsonenc *e, upb_msgval val, const upb_fielddef *f);
-static void jsonenc_msgfield(jsonenc *e, const upb_msg *msg,
-                             const upb_msgdef *m);
-static void jsonenc_msgfields(jsonenc *e, const upb_msg *msg,
-                              const upb_msgdef *m, bool first);
-static void jsonenc_value(jsonenc *e, const upb_msg *msg, const upb_msgdef *m);
+static void jsonenc_msg(jsonenc* e, const upb_msg* msg,
+                        const upb_MessageDef* m);
+static void jsonenc_scalar(jsonenc* e, upb_MessageValue val,
+                           const upb_FieldDef* f);
+static void jsonenc_msgfield(jsonenc* e, const upb_msg* msg,
+                             const upb_MessageDef* m);
+static void jsonenc_msgfields(jsonenc* e, const upb_msg* msg,
+                              const upb_MessageDef* m, bool first);
+static void jsonenc_value(jsonenc* e, const upb_msg* msg,
+                          const upb_MessageDef* m);
 
-UPB_NORETURN static void jsonenc_err(jsonenc *e, const char *msg) {
-  upb_status_seterrmsg(e->status, msg);
+UPB_NORETURN static void jsonenc_err(jsonenc* e, const char* msg) {
+  upb_Status_SetErrorMessage(e->status, msg);
   longjmp(e->err, 1);
 }
 
 UPB_PRINTF(2, 3)
-UPB_NORETURN static void jsonenc_errf(jsonenc *e, const char *fmt, ...) {
+UPB_NORETURN static void jsonenc_errf(jsonenc* e, const char* fmt, ...) {
   va_list argp;
   va_start(argp, fmt);
-  upb_status_vseterrf(e->status, fmt, argp);
+  upb_Status_VSetErrorFormat(e->status, fmt, argp);
   va_end(argp);
   longjmp(e->err, 1);
 }
 
-static upb_arena *jsonenc_arena(jsonenc *e) {
+static upb_Arena* jsonenc_arena(jsonenc* e) {
   /* Create lazily, since it's only needed for Any */
   if (!e->arena) {
-    e->arena = upb_arena_new();
+    e->arena = upb_Arena_New();
   }
   return e->arena;
 }
 
-static void jsonenc_putbytes(jsonenc *e, const void *data, size_t len) {
+static void jsonenc_putbytes(jsonenc* e, const void* data, size_t len) {
   size_t have = e->end - e->ptr;
   if (UPB_LIKELY(have >= len)) {
     memcpy(e->ptr, data, len);
@@ -97,12 +100,12 @@
   }
 }
 
-static void jsonenc_putstr(jsonenc *e, const char *str) {
+static void jsonenc_putstr(jsonenc* e, const char* str) {
   jsonenc_putbytes(e, str, strlen(str));
 }
 
 UPB_PRINTF(2, 3)
-static void jsonenc_printf(jsonenc *e, const char *fmt, ...) {
+static void jsonenc_printf(jsonenc* e, const char* fmt, ...) {
   size_t n;
   size_t have = e->end - e->ptr;
   va_list args;
@@ -119,7 +122,7 @@
   }
 }
 
-static void jsonenc_nanos(jsonenc *e, int32_t nanos) {
+static void jsonenc_nanos(jsonenc* e, int32_t nanos) {
   int digits = 9;
 
   if (nanos == 0) return;
@@ -135,12 +138,13 @@
   jsonenc_printf(e, ".%.*" PRId32, digits, nanos);
 }
 
-static void jsonenc_timestamp(jsonenc *e, const upb_msg *msg,
-                              const upb_msgdef *m) {
-  const upb_fielddef *seconds_f = upb_msgdef_itof(m, 1);
-  const upb_fielddef *nanos_f = upb_msgdef_itof(m, 2);
-  int64_t seconds = upb_msg_get(msg, seconds_f).int64_val;
-  int32_t nanos = upb_msg_get(msg, nanos_f).int32_val;
+static void jsonenc_timestamp(jsonenc* e, const upb_msg* msg,
+                              const upb_MessageDef* m) {
+  const upb_FieldDef* seconds_f =
+      upb_MessageDef_FindFieldByNumberWithSize(m, 1);
+  const upb_FieldDef* nanos_f = upb_MessageDef_FindFieldByNumberWithSize(m, 2);
+  int64_t seconds = upb_Message_Get(msg, seconds_f).int64_val;
+  int32_t nanos = upb_Message_Get(msg, nanos_f).int32_val;
   int L, N, I, J, K, hour, min, sec;
 
   if (seconds < -62135596800) {
@@ -177,11 +181,13 @@
   jsonenc_putstr(e, "Z\"");
 }
 
-static void jsonenc_duration(jsonenc *e, const upb_msg *msg, const upb_msgdef *m) {
-  const upb_fielddef *seconds_f = upb_msgdef_itof(m, 1);
-  const upb_fielddef *nanos_f = upb_msgdef_itof(m, 2);
-  int64_t seconds = upb_msg_get(msg, seconds_f).int64_val;
-  int32_t nanos = upb_msg_get(msg, nanos_f).int32_val;
+static void jsonenc_duration(jsonenc* e, const upb_msg* msg,
+                             const upb_MessageDef* m) {
+  const upb_FieldDef* seconds_f =
+      upb_MessageDef_FindFieldByNumberWithSize(m, 1);
+  const upb_FieldDef* nanos_f = upb_MessageDef_FindFieldByNumberWithSize(m, 2);
+  int64_t seconds = upb_Message_Get(msg, seconds_f).int64_val;
+  int32_t nanos = upb_Message_Get(msg, nanos_f).int32_val;
 
   if (seconds > 315576000000 || seconds < -315576000000 ||
       (seconds < 0) != (nanos < 0)) {
@@ -197,28 +203,28 @@
   jsonenc_putstr(e, "s\"");
 }
 
-static void jsonenc_enum(int32_t val, const upb_fielddef *f, jsonenc *e) {
-  const upb_enumdef *e_def = upb_fielddef_enumsubdef(f);
+static void jsonenc_enum(int32_t val, const upb_FieldDef* f, jsonenc* e) {
+  const upb_EnumDef* e_def = upb_FieldDef_EnumSubDef(f);
 
-  if (strcmp(upb_enumdef_fullname(e_def), "google.protobuf.NullValue") == 0) {
+  if (strcmp(upb_EnumDef_FullName(e_def), "google.protobuf.NullValue") == 0) {
     jsonenc_putstr(e, "null");
   } else {
-    const upb_enumvaldef *ev = upb_enumdef_lookupnum(e_def, val);
+    const upb_EnumValueDef* ev = upb_EnumDef_FindValueByNumber(e_def, val);
 
     if (ev) {
-      jsonenc_printf(e, "\"%s\"", upb_enumvaldef_name(ev));
+      jsonenc_printf(e, "\"%s\"", upb_EnumValueDef_Name(ev));
     } else {
       jsonenc_printf(e, "%" PRId32, val);
     }
   }
 }
 
-static void jsonenc_bytes(jsonenc *e, upb_strview str) {
+static void jsonenc_bytes(jsonenc* e, upb_StringView str) {
   /* This is the regular base64, not the "web-safe" version. */
   static const char base64[] =
       "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
-  const unsigned char *ptr = (unsigned char*)str.data;
-  const unsigned char *end = UPB_PTRADD(ptr, str.size);
+  const unsigned char* ptr = (unsigned char*)str.data;
+  const unsigned char* end = UPB_PTRADD(ptr, str.size);
   char buf[4];
 
   jsonenc_putstr(e, "\"");
@@ -252,9 +258,9 @@
   jsonenc_putstr(e, "\"");
 }
 
-static void jsonenc_stringbody(jsonenc *e, upb_strview str) {
-  const char *ptr = str.data;
-  const char *end = UPB_PTRADD(ptr, str.size);
+static void jsonenc_stringbody(jsonenc* e, upb_StringView str) {
+  const char* ptr = str.data;
+  const char* end = UPB_PTRADD(ptr, str.size);
 
   while (ptr < end) {
     switch (*ptr) {
@@ -293,13 +299,13 @@
   }
 }
 
-static void jsonenc_string(jsonenc *e, upb_strview str) {
+static void jsonenc_string(jsonenc* e, upb_StringView str) {
   jsonenc_putstr(e, "\"");
   jsonenc_stringbody(e, str);
   jsonenc_putstr(e, "\"");
 }
 
-static void jsonenc_double(jsonenc *e, const char *fmt, double val) {
+static void jsonenc_double(jsonenc* e, const char* fmt, double val) {
   if (val == INFINITY) {
     jsonenc_putstr(e, "\"Infinity\"");
   } else if (val == -INFINITY) {
@@ -307,7 +313,7 @@
   } else if (val != val) {
     jsonenc_putstr(e, "\"NaN\"");
   } else {
-    char *p = e->ptr;
+    char* p = e->ptr;
     jsonenc_printf(e, fmt, val);
 
     /* printf() is dependent on locales; sadly there is no easy and portable way
@@ -315,24 +321,25 @@
      * since JSON needs the latter. Arguably a hack, but it is simple and the
      * alternatives are far more complicated, platform-dependent, and/or larger
      * in code size. */
-    for (char *end = e->ptr; p < end; p++) {
+    for (char* end = e->ptr; p < end; p++) {
       if (*p == ',') *p = '.';
     }
   }
 }
 
-static void jsonenc_wrapper(jsonenc *e, const upb_msg *msg,
-                            const upb_msgdef *m) {
-  const upb_fielddef *val_f = upb_msgdef_itof(m, 1);
-  upb_msgval val = upb_msg_get(msg, val_f);
+static void jsonenc_wrapper(jsonenc* e, const upb_msg* msg,
+                            const upb_MessageDef* m) {
+  const upb_FieldDef* val_f = upb_MessageDef_FindFieldByNumberWithSize(m, 1);
+  upb_MessageValue val = upb_Message_Get(msg, val_f);
   jsonenc_scalar(e, val, val_f);
 }
 
-static const upb_msgdef *jsonenc_getanymsg(jsonenc *e, upb_strview type_url) {
+static const upb_MessageDef* jsonenc_getanymsg(jsonenc* e,
+                                               upb_StringView type_url) {
   /* Find last '/', if any. */
-  const char *end = type_url.data + type_url.size;
-  const char *ptr = end;
-  const upb_msgdef *ret;
+  const char* end = type_url.data + type_url.size;
+  const char* ptr = end;
+  const upb_MessageDef* ret;
 
   if (!e->ext_pool) {
     jsonenc_err(e, "Tried to encode Any, but no symtab was provided");
@@ -351,7 +358,7 @@
     }
   }
 
-  ret = upb_symtab_lookupmsg2(e->ext_pool, ptr, end - ptr);
+  ret = upb_DefPool_FindMessageByNameWithSize(e->ext_pool, ptr, end - ptr);
 
   if (!ret) {
     jsonenc_errf(e, "Couldn't find Any type: %.*s", (int)(end - ptr), ptr);
@@ -360,19 +367,21 @@
   return ret;
 
 badurl:
-  jsonenc_errf(
-      e, "Bad type URL: " UPB_STRVIEW_FORMAT, UPB_STRVIEW_ARGS(type_url));
+  jsonenc_errf(e, "Bad type URL: " UPB_STRINGVIEW_FORMAT,
+               UPB_STRINGVIEW_ARGS(type_url));
 }
 
-static void jsonenc_any(jsonenc *e, const upb_msg *msg, const upb_msgdef *m) {
-  const upb_fielddef *type_url_f = upb_msgdef_itof(m, 1);
-  const upb_fielddef *value_f = upb_msgdef_itof(m, 2);
-  upb_strview type_url = upb_msg_get(msg, type_url_f).str_val;
-  upb_strview value = upb_msg_get(msg, value_f).str_val;
-  const upb_msgdef *any_m = jsonenc_getanymsg(e, type_url);
-  const upb_msglayout *any_layout = upb_msgdef_layout(any_m);
-  upb_arena *arena = jsonenc_arena(e);
-  upb_msg *any = upb_msg_new(any_m, arena);
+static void jsonenc_any(jsonenc* e, const upb_msg* msg,
+                        const upb_MessageDef* m) {
+  const upb_FieldDef* type_url_f =
+      upb_MessageDef_FindFieldByNumberWithSize(m, 1);
+  const upb_FieldDef* value_f = upb_MessageDef_FindFieldByNumberWithSize(m, 2);
+  upb_StringView type_url = upb_Message_Get(msg, type_url_f).str_val;
+  upb_StringView value = upb_Message_Get(msg, value_f).str_val;
+  const upb_MessageDef* any_m = jsonenc_getanymsg(e, type_url);
+  const upb_MiniTable* any_layout = upb_MessageDef_MiniTable(any_m);
+  upb_Arena* arena = jsonenc_arena(e);
+  upb_msg* any = upb_Message_New(any_m, arena);
 
   if (upb_decode(value.data, value.size, any, any_layout, arena) !=
       kUpb_DecodeStatus_Ok) {
@@ -382,7 +391,7 @@
   jsonenc_putstr(e, "{\"@type\":");
   jsonenc_string(e, type_url);
 
-  if (upb_msgdef_wellknowntype(any_m) == UPB_WELLKNOWN_UNSPECIFIED) {
+  if (upb_MessageDef_WellKnownType(any_m) == kUpb_WellKnown_Unspecified) {
     /* Regular messages: {"@type": "...","foo": 1, "bar": 2} */
     jsonenc_msgfields(e, any, any_m, false);
   } else {
@@ -394,7 +403,7 @@
   jsonenc_putstr(e, "}");
 }
 
-static void jsonenc_putsep(jsonenc *e, const char *str, bool *first) {
+static void jsonenc_putsep(jsonenc* e, const char* str, bool* first) {
   if (*first) {
     *first = false;
   } else {
@@ -402,9 +411,9 @@
   }
 }
 
-static void jsonenc_fieldpath(jsonenc *e, upb_strview path) {
-  const char *ptr = path.data;
-  const char *end = ptr + path.size;
+static void jsonenc_fieldpath(jsonenc* e, upb_StringView path) {
+  const char* ptr = path.data;
+  const char* end = ptr + path.size;
 
   while (ptr < end) {
     char ch = *ptr;
@@ -423,65 +432,66 @@
   }
 }
 
-static void jsonenc_fieldmask(jsonenc *e, const upb_msg *msg,
-                              const upb_msgdef *m) {
-  const upb_fielddef *paths_f = upb_msgdef_itof(m, 1);
-  const upb_array *paths = upb_msg_get(msg, paths_f).array_val;
+static void jsonenc_fieldmask(jsonenc* e, const upb_msg* msg,
+                              const upb_MessageDef* m) {
+  const upb_FieldDef* paths_f = upb_MessageDef_FindFieldByNumberWithSize(m, 1);
+  const upb_Array* paths = upb_Message_Get(msg, paths_f).array_val;
   bool first = true;
   size_t i, n = 0;
 
-  if (paths) n = upb_array_size(paths);
+  if (paths) n = upb_Array_Size(paths);
 
   jsonenc_putstr(e, "\"");
 
   for (i = 0; i < n; i++) {
     jsonenc_putsep(e, ",", &first);
-    jsonenc_fieldpath(e, upb_array_get(paths, i).str_val);
+    jsonenc_fieldpath(e, upb_Array_Get(paths, i).str_val);
   }
 
   jsonenc_putstr(e, "\"");
 }
 
-static void jsonenc_struct(jsonenc *e, const upb_msg *msg,
-                           const upb_msgdef *m) {
-  const upb_fielddef *fields_f = upb_msgdef_itof(m, 1);
-  const upb_map *fields = upb_msg_get(msg, fields_f).map_val;
-  const upb_msgdef *entry_m = upb_fielddef_msgsubdef(fields_f);
-  const upb_fielddef *value_f = upb_msgdef_itof(entry_m, 2);
-  size_t iter = UPB_MAP_BEGIN;
+static void jsonenc_struct(jsonenc* e, const upb_msg* msg,
+                           const upb_MessageDef* m) {
+  const upb_FieldDef* fields_f = upb_MessageDef_FindFieldByNumberWithSize(m, 1);
+  const upb_Map* fields = upb_Message_Get(msg, fields_f).map_val;
+  const upb_MessageDef* entry_m = upb_FieldDef_MessageSubDef(fields_f);
+  const upb_FieldDef* value_f =
+      upb_MessageDef_FindFieldByNumberWithSize(entry_m, 2);
+  size_t iter = kUpb_Map_Begin;
   bool first = true;
 
   jsonenc_putstr(e, "{");
 
   if (fields) {
-    while (upb_mapiter_next(fields, &iter)) {
-      upb_msgval key = upb_mapiter_key(fields, iter);
-      upb_msgval val = upb_mapiter_value(fields, iter);
+    while (upb_MapIterator_Next(fields, &iter)) {
+      upb_MessageValue key = upb_MapIterator_Key(fields, iter);
+      upb_MessageValue val = upb_MapIterator_Value(fields, iter);
 
       jsonenc_putsep(e, ",", &first);
       jsonenc_string(e, key.str_val);
       jsonenc_putstr(e, ":");
-      jsonenc_value(e, val.msg_val, upb_fielddef_msgsubdef(value_f));
+      jsonenc_value(e, val.msg_val, upb_FieldDef_MessageSubDef(value_f));
     }
   }
 
   jsonenc_putstr(e, "}");
 }
 
-static void jsonenc_listvalue(jsonenc *e, const upb_msg *msg,
-                              const upb_msgdef *m) {
-  const upb_fielddef *values_f = upb_msgdef_itof(m, 1);
-  const upb_msgdef *values_m = upb_fielddef_msgsubdef(values_f);
-  const upb_array *values = upb_msg_get(msg, values_f).array_val;
+static void jsonenc_listvalue(jsonenc* e, const upb_msg* msg,
+                              const upb_MessageDef* m) {
+  const upb_FieldDef* values_f = upb_MessageDef_FindFieldByNumberWithSize(m, 1);
+  const upb_MessageDef* values_m = upb_FieldDef_MessageSubDef(values_f);
+  const upb_Array* values = upb_Message_Get(msg, values_f).array_val;
   size_t i;
   bool first = true;
 
   jsonenc_putstr(e, "[");
 
   if (values) {
-    const size_t size = upb_array_size(values);
+    const size_t size = upb_Array_Size(values);
     for (i = 0; i < size; i++) {
-      upb_msgval elem = upb_array_get(values, i);
+      upb_MessageValue elem = upb_Array_Get(values, i);
 
       jsonenc_putsep(e, ",", &first);
       jsonenc_value(e, elem.msg_val, values_m);
@@ -491,17 +501,18 @@
   jsonenc_putstr(e, "]");
 }
 
-static void jsonenc_value(jsonenc *e, const upb_msg *msg, const upb_msgdef *m) {
+static void jsonenc_value(jsonenc* e, const upb_msg* msg,
+                          const upb_MessageDef* m) {
   /* TODO(haberman): do we want a reflection method to get oneof case? */
-  size_t iter = UPB_MSG_BEGIN;
-  const upb_fielddef *f;
-  upb_msgval val;
+  size_t iter = kUpb_Message_Begin;
+  const upb_FieldDef* f;
+  upb_MessageValue val;
 
-  if (!upb_msg_next(msg, m, NULL,  &f, &val, &iter)) {
+  if (!upb_Message_Next(msg, m, NULL, &f, &val, &iter)) {
     jsonenc_err(e, "No value set in Value proto");
   }
 
-  switch (upb_fielddef_number(f)) {
+  switch (upb_FieldDef_Number(f)) {
     case 1:
       jsonenc_putstr(e, "null");
       break;
@@ -515,113 +526,115 @@
       jsonenc_putstr(e, val.bool_val ? "true" : "false");
       break;
     case 5:
-      jsonenc_struct(e, val.msg_val, upb_fielddef_msgsubdef(f));
+      jsonenc_struct(e, val.msg_val, upb_FieldDef_MessageSubDef(f));
       break;
     case 6:
-      jsonenc_listvalue(e, val.msg_val, upb_fielddef_msgsubdef(f));
+      jsonenc_listvalue(e, val.msg_val, upb_FieldDef_MessageSubDef(f));
       break;
   }
 }
 
-static void jsonenc_msgfield(jsonenc *e, const upb_msg *msg,
-                             const upb_msgdef *m) {
-  switch (upb_msgdef_wellknowntype(m)) {
-    case UPB_WELLKNOWN_UNSPECIFIED:
+static void jsonenc_msgfield(jsonenc* e, const upb_msg* msg,
+                             const upb_MessageDef* m) {
+  switch (upb_MessageDef_WellKnownType(m)) {
+    case kUpb_WellKnown_Unspecified:
       jsonenc_msg(e, msg, m);
       break;
-    case UPB_WELLKNOWN_ANY:
+    case kUpb_WellKnown_Any:
       jsonenc_any(e, msg, m);
       break;
-    case UPB_WELLKNOWN_FIELDMASK:
+    case kUpb_WellKnown_FieldMask:
       jsonenc_fieldmask(e, msg, m);
       break;
-    case UPB_WELLKNOWN_DURATION:
+    case kUpb_WellKnown_Duration:
       jsonenc_duration(e, msg, m);
       break;
-    case UPB_WELLKNOWN_TIMESTAMP:
+    case kUpb_WellKnown_Timestamp:
       jsonenc_timestamp(e, msg, m);
       break;
-    case UPB_WELLKNOWN_DOUBLEVALUE:
-    case UPB_WELLKNOWN_FLOATVALUE:
-    case UPB_WELLKNOWN_INT64VALUE:
-    case UPB_WELLKNOWN_UINT64VALUE:
-    case UPB_WELLKNOWN_INT32VALUE:
-    case UPB_WELLKNOWN_UINT32VALUE:
-    case UPB_WELLKNOWN_STRINGVALUE:
-    case UPB_WELLKNOWN_BYTESVALUE:
-    case UPB_WELLKNOWN_BOOLVALUE:
+    case kUpb_WellKnown_DoubleValue:
+    case kUpb_WellKnown_FloatValue:
+    case kUpb_WellKnown_Int64Value:
+    case kUpb_WellKnown_UInt64Value:
+    case kUpb_WellKnown_Int32Value:
+    case kUpb_WellKnown_UInt32Value:
+    case kUpb_WellKnown_StringValue:
+    case kUpb_WellKnown_BytesValue:
+    case kUpb_WellKnown_BoolValue:
       jsonenc_wrapper(e, msg, m);
       break;
-    case UPB_WELLKNOWN_VALUE:
+    case kUpb_WellKnown_Value:
       jsonenc_value(e, msg, m);
       break;
-    case UPB_WELLKNOWN_LISTVALUE:
+    case kUpb_WellKnown_ListValue:
       jsonenc_listvalue(e, msg, m);
       break;
-    case UPB_WELLKNOWN_STRUCT:
+    case kUpb_WellKnown_Struct:
       jsonenc_struct(e, msg, m);
       break;
   }
 }
 
-static void jsonenc_scalar(jsonenc *e, upb_msgval val, const upb_fielddef *f) {
-  switch (upb_fielddef_type(f)) {
-    case UPB_TYPE_BOOL:
+static void jsonenc_scalar(jsonenc* e, upb_MessageValue val,
+                           const upb_FieldDef* f) {
+  switch (upb_FieldDef_CType(f)) {
+    case kUpb_CType_Bool:
       jsonenc_putstr(e, val.bool_val ? "true" : "false");
       break;
-    case UPB_TYPE_FLOAT:
+    case kUpb_CType_Float:
       jsonenc_double(e, "%.9g", val.float_val);
       break;
-    case UPB_TYPE_DOUBLE:
+    case kUpb_CType_Double:
       jsonenc_double(e, "%.17g", val.double_val);
       break;
-    case UPB_TYPE_INT32:
+    case kUpb_CType_Int32:
       jsonenc_printf(e, "%" PRId32, val.int32_val);
       break;
-    case UPB_TYPE_UINT32:
+    case kUpb_CType_UInt32:
       jsonenc_printf(e, "%" PRIu32, val.uint32_val);
       break;
-    case UPB_TYPE_INT64:
+    case kUpb_CType_Int64:
       jsonenc_printf(e, "\"%" PRId64 "\"", val.int64_val);
       break;
-    case UPB_TYPE_UINT64:
+    case kUpb_CType_UInt64:
       jsonenc_printf(e, "\"%" PRIu64 "\"", val.uint64_val);
       break;
-    case UPB_TYPE_STRING:
+    case kUpb_CType_String:
       jsonenc_string(e, val.str_val);
       break;
-    case UPB_TYPE_BYTES:
+    case kUpb_CType_Bytes:
       jsonenc_bytes(e, val.str_val);
       break;
-    case UPB_TYPE_ENUM:
+    case kUpb_CType_Enum:
       jsonenc_enum(val.int32_val, f, e);
       break;
-    case UPB_TYPE_MESSAGE:
-      jsonenc_msgfield(e, val.msg_val, upb_fielddef_msgsubdef(f));
+    case kUpb_CType_Message:
+      jsonenc_msgfield(e, val.msg_val, upb_FieldDef_MessageSubDef(f));
       break;
   }
 }
 
-static void jsonenc_mapkey(jsonenc *e, upb_msgval val, const upb_fielddef *f) {
+static void jsonenc_mapkey(jsonenc* e, upb_MessageValue val,
+                           const upb_FieldDef* f) {
   jsonenc_putstr(e, "\"");
 
-  switch (upb_fielddef_type(f)) {
-    case UPB_TYPE_BOOL:
+  switch (upb_FieldDef_CType(f)) {
+    case kUpb_CType_Bool:
       jsonenc_putstr(e, val.bool_val ? "true" : "false");
       break;
-    case UPB_TYPE_INT32:
+    case kUpb_CType_Int32:
       jsonenc_printf(e, "%" PRId32, val.int32_val);
       break;
-    case UPB_TYPE_UINT32:
+    case kUpb_CType_UInt32:
       jsonenc_printf(e, "%" PRIu32, val.uint32_val);
       break;
-    case UPB_TYPE_INT64:
+    case kUpb_CType_Int64:
       jsonenc_printf(e, "%" PRId64, val.int64_val);
       break;
-    case UPB_TYPE_UINT64:
+    case kUpb_CType_UInt64:
       jsonenc_printf(e, "%" PRIu64, val.uint64_val);
       break;
-    case UPB_TYPE_STRING:
+    case kUpb_CType_String:
       jsonenc_stringbody(e, val.str_val);
       break;
     default:
@@ -631,102 +644,105 @@
   jsonenc_putstr(e, "\":");
 }
 
-static void jsonenc_array(jsonenc *e, const upb_array *arr,
-                         const upb_fielddef *f) {
+static void jsonenc_array(jsonenc* e, const upb_Array* arr,
+                          const upb_FieldDef* f) {
   size_t i;
-  size_t size = arr ? upb_array_size(arr) : 0;
+  size_t size = arr ? upb_Array_Size(arr) : 0;
   bool first = true;
 
   jsonenc_putstr(e, "[");
 
   for (i = 0; i < size; i++) {
     jsonenc_putsep(e, ",", &first);
-    jsonenc_scalar(e, upb_array_get(arr, i), f);
+    jsonenc_scalar(e, upb_Array_Get(arr, i), f);
   }
 
   jsonenc_putstr(e, "]");
 }
 
-static void jsonenc_map(jsonenc *e, const upb_map *map, const upb_fielddef *f) {
-  const upb_msgdef *entry = upb_fielddef_msgsubdef(f);
-  const upb_fielddef *key_f = upb_msgdef_itof(entry, 1);
-  const upb_fielddef *val_f = upb_msgdef_itof(entry, 2);
-  size_t iter = UPB_MAP_BEGIN;
+static void jsonenc_map(jsonenc* e, const upb_Map* map, const upb_FieldDef* f) {
+  const upb_MessageDef* entry = upb_FieldDef_MessageSubDef(f);
+  const upb_FieldDef* key_f =
+      upb_MessageDef_FindFieldByNumberWithSize(entry, 1);
+  const upb_FieldDef* val_f =
+      upb_MessageDef_FindFieldByNumberWithSize(entry, 2);
+  size_t iter = kUpb_Map_Begin;
   bool first = true;
 
   jsonenc_putstr(e, "{");
 
   if (map) {
-    while (upb_mapiter_next(map, &iter)) {
+    while (upb_MapIterator_Next(map, &iter)) {
       jsonenc_putsep(e, ",", &first);
-      jsonenc_mapkey(e, upb_mapiter_key(map, iter), key_f);
-      jsonenc_scalar(e, upb_mapiter_value(map, iter), val_f);
+      jsonenc_mapkey(e, upb_MapIterator_Key(map, iter), key_f);
+      jsonenc_scalar(e, upb_MapIterator_Value(map, iter), val_f);
     }
   }
 
   jsonenc_putstr(e, "}");
 }
 
-static void jsonenc_fieldval(jsonenc *e, const upb_fielddef *f,
-                             upb_msgval val, bool *first) {
-  const char *name;
+static void jsonenc_fieldval(jsonenc* e, const upb_FieldDef* f,
+                             upb_MessageValue val, bool* first) {
+  const char* name;
 
   jsonenc_putsep(e, ",", first);
 
-  if (upb_fielddef_isextension(f)) {
+  if (upb_FieldDef_IsExtension(f)) {
     // TODO: For MessageSet, I would have expected this to print the message
     // name here, but Python doesn't appear to do this. We should do more
     // research here about what various implementations do.
-    jsonenc_printf(e, "\"[%s]\":", upb_fielddef_fullname(f));
+    jsonenc_printf(e, "\"[%s]\":", upb_FieldDef_FullName(f));
   } else {
-    if (e->options & UPB_JSONENC_PROTONAMES) {
-      name = upb_fielddef_name(f);
+    if (e->options & upb_JsonEncode_UseProtoNames) {
+      name = upb_FieldDef_Name(f);
     } else {
-      name = upb_fielddef_jsonname(f);
+      name = upb_FieldDef_JsonName(f);
     }
     jsonenc_printf(e, "\"%s\":", name);
   }
 
-  if (upb_fielddef_ismap(f)) {
+  if (upb_FieldDef_IsMap(f)) {
     jsonenc_map(e, val.map_val, f);
-  } else if (upb_fielddef_isseq(f)) {
+  } else if (upb_FieldDef_IsRepeated(f)) {
     jsonenc_array(e, val.array_val, f);
   } else {
     jsonenc_scalar(e, val, f);
   }
 }
 
-static void jsonenc_msgfields(jsonenc *e, const upb_msg *msg,
-                              const upb_msgdef *m, bool first) {
-  upb_msgval val;
-  const upb_fielddef *f;
+static void jsonenc_msgfields(jsonenc* e, const upb_msg* msg,
+                              const upb_MessageDef* m, bool first) {
+  upb_MessageValue val;
+  const upb_FieldDef* f;
 
-  if (e->options & UPB_JSONENC_EMITDEFAULTS) {
+  if (e->options & upb_JsonEncode_EmitDefaults) {
     /* Iterate over all fields. */
     int i = 0;
-    int n = upb_msgdef_fieldcount(m);
+    int n = upb_MessageDef_FieldCount(m);
     for (i = 0; i < n; i++) {
-      f = upb_msgdef_field(m, i);
-      if (!upb_fielddef_haspresence(f) || upb_msg_has(msg, f)) {
-        jsonenc_fieldval(e, f, upb_msg_get(msg, f), &first);
+      f = upb_MessageDef_Field(m, i);
+      if (!upb_FieldDef_HasPresence(f) || upb_Message_Has(msg, f)) {
+        jsonenc_fieldval(e, f, upb_Message_Get(msg, f), &first);
       }
     }
   } else {
     /* Iterate over non-empty fields. */
-    size_t iter = UPB_MSG_BEGIN;
-    while (upb_msg_next(msg, m, e->ext_pool, &f, &val, &iter)) {
+    size_t iter = kUpb_Message_Begin;
+    while (upb_Message_Next(msg, m, e->ext_pool, &f, &val, &iter)) {
       jsonenc_fieldval(e, f, val, &first);
     }
   }
 }
 
-static void jsonenc_msg(jsonenc *e, const upb_msg *msg, const upb_msgdef *m) {
+static void jsonenc_msg(jsonenc* e, const upb_msg* msg,
+                        const upb_MessageDef* m) {
   jsonenc_putstr(e, "{");
   jsonenc_msgfields(e, msg, m, true);
   jsonenc_putstr(e, "}");
 }
 
-static size_t jsonenc_nullz(jsonenc *e, size_t size) {
+static size_t jsonenc_nullz(jsonenc* e, size_t size) {
   size_t ret = e->ptr - e->buf + e->overflow;
 
   if (size > 0) {
@@ -737,9 +753,9 @@
   return ret;
 }
 
-size_t upb_json_encode(const upb_msg *msg, const upb_msgdef *m,
-                       const upb_symtab *ext_pool, int options, char *buf,
-                       size_t size, upb_status *status) {
+size_t upb_JsonEncode(const upb_msg* msg, const upb_MessageDef* m,
+                      const upb_DefPool* ext_pool, int options, char* buf,
+                      size_t size, upb_Status* status) {
   jsonenc e;
 
   e.buf = buf;
@@ -754,6 +770,6 @@
   if (setjmp(e.err)) return -1;
 
   jsonenc_msgfield(&e, msg, m);
-  if (e.arena) upb_arena_free(e.arena);
+  if (e.arena) upb_Arena_Free(e.arena);
   return jsonenc_nullz(&e, size);
 }