upb/reflection/def_pool.c - third_party/protobuf - Git at Google

 // Protocol Buffers - Google's data interchange format
 // Copyright 2023 Google LLC.  All rights reserved.
 //
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file or at
 // https://developers.google.com/open-source/licenses/bsd

 #include "upb/reflection/internal/def_pool.h"

 #include "upb/base/status.h"
 #include "upb/hash/int_table.h"
 #include "upb/hash/str_table.h"
 #include "upb/mem/alloc.h"
 #include "upb/mem/arena.h"
 #include "upb/reflection/def_type.h"
 #include "upb/reflection/file_def.h"
 #include "upb/reflection/internal/def_builder.h"
 #include "upb/reflection/internal/enum_def.h"
 #include "upb/reflection/internal/enum_value_def.h"
 #include "upb/reflection/internal/field_def.h"
 #include "upb/reflection/internal/file_def.h"
 #include "upb/reflection/internal/message_def.h"
 #include "upb/reflection/internal/service_def.h"
 #include "upb/reflection/internal/upb_edition_defaults.h"

 // Must be last.
 #include "upb/port/def.inc"

 struct upb_DefPool {
   upb_Arena* arena;
   upb_strtable syms;   // full_name -> packed def ptr
   upb_strtable files;  // file_name -> (upb_FileDef*)
   upb_inttable exts;   // (upb_MiniTableExtension*) -> (upb_FieldDef*)
   upb_ExtensionRegistry* extreg;
   const UPB_DESC(FeatureSetDefaults) * feature_set_defaults;
   upb_MiniTablePlatform platform;
   void* scratch_data;
   size_t scratch_size;
   size_t bytes_loaded;
 };

 void upb_DefPool_Free(upb_DefPool* s) {
   upb_Arena_Free(s->arena);
   upb_gfree(s->scratch_data);
   upb_gfree(s);
 }

 static const char serialized_defaults[] = UPB_INTERNAL_UPB_EDITION_DEFAULTS;

 upb_DefPool* upb_DefPool_New(void) {
   upb_DefPool* s = upb_gmalloc(sizeof(*s));
   if (!s) return NULL;

   s->arena = upb_Arena_New();
   s->bytes_loaded = 0;

   s->scratch_size = 240;
   s->scratch_data = upb_gmalloc(s->scratch_size);
   if (!s->scratch_data) goto err;

   if (!upb_strtable_init(&s->syms, 32, s->arena)) goto err;
   if (!upb_strtable_init(&s->files, 4, s->arena)) goto err;
   if (!upb_inttable_init(&s->exts, s->arena)) goto err;

   s->extreg = upb_ExtensionRegistry_New(s->arena);
   if (!s->extreg) goto err;

   s->platform = kUpb_MiniTablePlatform_Native;

   upb_Status status;
   if (!upb_DefPool_SetFeatureSetDefaults(
           s, serialized_defaults, sizeof(serialized_defaults) - 1, &status)) {
     goto err;
   }

   if (!s->feature_set_defaults) goto err;

   return s;

 err:
   upb_DefPool_Free(s);
   return NULL;
 }

 const UPB_DESC(FeatureSetDefaults) *
     upb_DefPool_FeatureSetDefaults(const upb_DefPool* s) {
   return s->feature_set_defaults;
 }

 bool upb_DefPool_SetFeatureSetDefaults(upb_DefPool* s,
                                        const char* serialized_defaults,
                                        size_t serialized_len,
                                        upb_Status* status) {
   const UPB_DESC(FeatureSetDefaults)* defaults = UPB_DESC(
       FeatureSetDefaults_parse)(serialized_defaults, serialized_len, s->arena);
   if (!defaults) {
     upb_Status_SetErrorFormat(status, "Failed to parse defaults");
     return false;
   }
   if (upb_strtable_count(&s->files) > 0) {
     upb_Status_SetErrorFormat(status,
                               "Feature set defaults can't be changed once the "
                               "pool has started building");
     return false;
   }
   int min_edition = UPB_DESC(FeatureSetDefaults_minimum_edition(defaults));
   int max_edition = UPB_DESC(FeatureSetDefaults_maximum_edition(defaults));
   if (min_edition > max_edition) {
     upb_Status_SetErrorFormat(status, "Invalid edition range %s to %s",
                               upb_FileDef_EditionName(min_edition),
                               upb_FileDef_EditionName(max_edition));
     return false;
   }
   size_t size;
   const UPB_DESC(
       FeatureSetDefaults_FeatureSetEditionDefault)* const* default_list =
       UPB_DESC(FeatureSetDefaults_defaults(defaults, &size));
   int prev_edition = UPB_DESC(EDITION_UNKNOWN);
   for (size_t i = 0; i < size; ++i) {
     int edition = UPB_DESC(
         FeatureSetDefaults_FeatureSetEditionDefault_edition(default_list[i]));
     if (edition == UPB_DESC(EDITION_UNKNOWN)) {
       upb_Status_SetErrorFormat(status, "Invalid edition UNKNOWN specified");
       return false;
     }
     if (edition <= prev_edition) {
       upb_Status_SetErrorFormat(status,
                                 "Feature set defaults are not strictly "
                                 "increasing, %s is greater than or equal to %s",
                                 upb_FileDef_EditionName(prev_edition),
                                 upb_FileDef_EditionName(edition));
       return false;
     }
     prev_edition = edition;
   }

   // Copy the defaults into the pool.
   s->feature_set_defaults = defaults;
   return true;
 }

 bool _upb_DefPool_InsertExt(upb_DefPool* s, const upb_MiniTableExtension* ext,
                             const upb_FieldDef* f) {
   return upb_inttable_insert(&s->exts, (uintptr_t)ext, upb_value_constptr(f),
                              s->arena);
 }

 bool _upb_DefPool_InsertSym(upb_DefPool* s, upb_StringView sym, upb_value v,
                             upb_Status* status) {
   // TODO: table should support an operation "tryinsert" to avoid the double
   // lookup.
   if (upb_strtable_lookup2(&s->syms, sym.data, sym.size, NULL)) {
     upb_Status_SetErrorFormat(status, "duplicate symbol '%s'", sym.data);
     return false;
   }
   if (!upb_strtable_insert(&s->syms, sym.data, sym.size, v, s->arena)) {
     upb_Status_SetErrorMessage(status, "out of memory");
     return false;
   }
   return true;
 }

 static const void* _upb_DefPool_Unpack(const upb_DefPool* s, const char* sym,
                                        size_t size, upb_deftype_t type) {
   upb_value v;
   return upb_strtable_lookup2(&s->syms, sym, size, &v)
              ? _upb_DefType_Unpack(v, type)
              : NULL;
 }

 bool _upb_DefPool_LookupSym(const upb_DefPool* s, const char* sym, size_t size,
                             upb_value* v) {
   return upb_strtable_lookup2(&s->syms, sym, size, v);
 }

 upb_ExtensionRegistry* _upb_DefPool_ExtReg(const upb_DefPool* s) {
   return s->extreg;
 }

 void** _upb_DefPool_ScratchData(const upb_DefPool* s) {
   return (void**)&s->scratch_data;
 }

 size_t* _upb_DefPool_ScratchSize(const upb_DefPool* s) {
   return (size_t*)&s->scratch_size;
 }

 void _upb_DefPool_SetPlatform(upb_DefPool* s, upb_MiniTablePlatform platform) {
   assert(upb_strtable_count(&s->files) == 0);
   s->platform = platform;
 }

 const upb_MessageDef* upb_DefPool_FindMessageByName(const upb_DefPool* s,
                                                     const char* sym) {
   return _upb_DefPool_Unpack(s, sym, strlen(sym), UPB_DEFTYPE_MSG);
 }

 const upb_MessageDef* upb_DefPool_FindMessageByNameWithSize(
     const upb_DefPool* s, const char* sym, size_t len) {
   return _upb_DefPool_Unpack(s, sym, len, UPB_DEFTYPE_MSG);
 }

 const upb_EnumDef* upb_DefPool_FindEnumByName(const upb_DefPool* s,
                                               const char* sym) {
   return _upb_DefPool_Unpack(s, sym, strlen(sym), UPB_DEFTYPE_ENUM);
 }

 const upb_EnumValueDef* upb_DefPool_FindEnumByNameval(const upb_DefPool* s,
                                                       const char* sym) {
   return _upb_DefPool_Unpack(s, sym, strlen(sym), UPB_DEFTYPE_ENUMVAL);
 }

 const upb_FileDef* upb_DefPool_FindFileByName(const upb_DefPool* s,
                                               const char* name) {
   upb_value v;
   return upb_strtable_lookup(&s->files, name, &v) ? upb_value_getconstptr(v)
                                                   : NULL;
 }

 const upb_FileDef* upb_DefPool_FindFileByNameWithSize(const upb_DefPool* s,
                                                       const char* name,
                                                       size_t len) {
   upb_value v;
   return upb_strtable_lookup2(&s->files, name, len, &v)
              ? upb_value_getconstptr(v)
              : NULL;
 }

 const upb_FieldDef* upb_DefPool_FindExtensionByNameWithSize(
     const upb_DefPool* s, const char* name, size_t size) {
   upb_value v;
   if (!upb_strtable_lookup2(&s->syms, name, size, &v)) return NULL;

   switch (_upb_DefType_Type(v)) {
     case UPB_DEFTYPE_FIELD:
       return _upb_DefType_Unpack(v, UPB_DEFTYPE_FIELD);
     case UPB_DEFTYPE_MSG: {
       const upb_MessageDef* m = _upb_DefType_Unpack(v, UPB_DEFTYPE_MSG);
       return _upb_MessageDef_InMessageSet(m)
                  ? upb_MessageDef_NestedExtension(m, 0)
                  : NULL;
     }
     default:
       break;
   }

   return NULL;
 }

 const upb_FieldDef* upb_DefPool_FindExtensionByName(const upb_DefPool* s,
                                                     const char* sym) {
   return upb_DefPool_FindExtensionByNameWithSize(s, sym, strlen(sym));
 }

 const upb_ServiceDef* upb_DefPool_FindServiceByName(const upb_DefPool* s,
                                                     const char* name) {
   return _upb_DefPool_Unpack(s, name, strlen(name), UPB_DEFTYPE_SERVICE);
 }

 const upb_ServiceDef* upb_DefPool_FindServiceByNameWithSize(
     const upb_DefPool* s, const char* name, size_t size) {
   return _upb_DefPool_Unpack(s, name, size, UPB_DEFTYPE_SERVICE);
 }

 const upb_FileDef* upb_DefPool_FindFileContainingSymbol(const upb_DefPool* s,
                                                         const char* name) {
   upb_value v;
   // TODO: non-extension fields and oneofs.
   if (upb_strtable_lookup(&s->syms, name, &v)) {
     switch (_upb_DefType_Type(v)) {
       case UPB_DEFTYPE_EXT: {
         const upb_FieldDef* f = _upb_DefType_Unpack(v, UPB_DEFTYPE_EXT);
         return upb_FieldDef_File(f);
       }
       case UPB_DEFTYPE_MSG: {
         const upb_MessageDef* m = _upb_DefType_Unpack(v, UPB_DEFTYPE_MSG);
         return upb_MessageDef_File(m);
       }
       case UPB_DEFTYPE_ENUM: {
         const upb_EnumDef* e = _upb_DefType_Unpack(v, UPB_DEFTYPE_ENUM);
         return upb_EnumDef_File(e);
       }
       case UPB_DEFTYPE_ENUMVAL: {
         const upb_EnumValueDef* ev =
             _upb_DefType_Unpack(v, UPB_DEFTYPE_ENUMVAL);
         return upb_EnumDef_File(upb_EnumValueDef_Enum(ev));
       }
       case UPB_DEFTYPE_SERVICE: {
         const upb_ServiceDef* service =
             _upb_DefType_Unpack(v, UPB_DEFTYPE_SERVICE);
         return upb_ServiceDef_File(service);
       }
       default:
         UPB_UNREACHABLE();
     }
   }

   const char* last_dot = strrchr(name, '.');
   if (last_dot) {
     const upb_MessageDef* parent =
         upb_DefPool_FindMessageByNameWithSize(s, name, last_dot - name);
     if (parent) {
       const char* shortname = last_dot + 1;
       if (upb_MessageDef_FindByNameWithSize(parent, shortname,
                                             strlen(shortname), NULL, NULL)) {
         return upb_MessageDef_File(parent);
       }
     }
   }

   return NULL;
 }

 static void remove_filedef(upb_DefPool* s, upb_FileDef* file) {
   intptr_t iter = UPB_INTTABLE_BEGIN;
   upb_StringView key;
   upb_value val;
   while (upb_strtable_next2(&s->syms, &key, &val, &iter)) {
     const upb_FileDef* f;
     switch (_upb_DefType_Type(val)) {
       case UPB_DEFTYPE_EXT:
         f = upb_FieldDef_File(_upb_DefType_Unpack(val, UPB_DEFTYPE_EXT));
         break;
       case UPB_DEFTYPE_MSG:
         f = upb_MessageDef_File(_upb_DefType_Unpack(val, UPB_DEFTYPE_MSG));
         break;
       case UPB_DEFTYPE_ENUM:
         f = upb_EnumDef_File(_upb_DefType_Unpack(val, UPB_DEFTYPE_ENUM));
         break;
       case UPB_DEFTYPE_ENUMVAL:
         f = upb_EnumDef_File(upb_EnumValueDef_Enum(
             _upb_DefType_Unpack(val, UPB_DEFTYPE_ENUMVAL)));
         break;
       case UPB_DEFTYPE_SERVICE:
         f = upb_ServiceDef_File(_upb_DefType_Unpack(val, UPB_DEFTYPE_SERVICE));
         break;
       default:
         UPB_UNREACHABLE();
     }

     if (f == file) upb_strtable_removeiter(&s->syms, &iter);
   }
 }

 static const upb_FileDef* upb_DefBuilder_AddFileToPool(
     upb_DefBuilder* const builder, upb_DefPool* const s,
     const UPB_DESC(FileDescriptorProto) * const file_proto,
     const upb_StringView name, upb_Status* const status) {
   if (UPB_SETJMP(builder->err) != 0) {
     UPB_ASSERT(!upb_Status_IsOk(status));
     if (builder->file) {
       remove_filedef(s, builder->file);
       builder->file = NULL;
     }
   } else if (!builder->arena || !builder->tmp_arena ||
              !upb_strtable_init(&builder->feature_cache, 16,
                                 builder->tmp_arena) ||
              !(builder->legacy_features =
                    UPB_DESC(FeatureSet_new)(builder->tmp_arena))) {
     _upb_DefBuilder_OomErr(builder);
   } else {
     _upb_FileDef_Create(builder, file_proto);
     upb_strtable_insert(&s->files, name.data, name.size,
                         upb_value_constptr(builder->file), builder->arena);
     UPB_ASSERT(upb_Status_IsOk(status));
     upb_Arena_Fuse(s->arena, builder->arena);
   }

   if (builder->arena) upb_Arena_Free(builder->arena);
   if (builder->tmp_arena) upb_Arena_Free(builder->tmp_arena);
   return builder->file;
 }

 static const upb_FileDef* _upb_DefPool_AddFile(
     upb_DefPool* s, const UPB_DESC(FileDescriptorProto) * file_proto,
     const upb_MiniTableFile* layout, upb_Status* status) {
   const upb_StringView name = UPB_DESC(FileDescriptorProto_name)(file_proto);

   // Determine whether we already know about this file.
   {
     upb_value v;
     if (upb_strtable_lookup2(&s->files, name.data, name.size, &v)) {
       upb_Status_SetErrorFormat(status,
                                 "duplicate file name " UPB_STRINGVIEW_FORMAT,
                                 UPB_STRINGVIEW_ARGS(name));
       return NULL;
     }
   }

   upb_DefBuilder ctx = {
       .symtab = s,
       .tmp_buf = NULL,
       .tmp_buf_size = 0,
       .layout = layout,
       .platform = s->platform,
       .msg_count = 0,
       .enum_count = 0,
       .ext_count = 0,
       .status = status,
       .file = NULL,
       .arena = upb_Arena_New(),
       .tmp_arena = upb_Arena_New(),
   };

   return upb_DefBuilder_AddFileToPool(&ctx, s, file_proto, name, status);
 }

 const upb_FileDef* upb_DefPool_AddFile(upb_DefPool* s,
                                        const UPB_DESC(FileDescriptorProto) *
                                            file_proto,
                                        upb_Status* status) {
   return _upb_DefPool_AddFile(s, file_proto, NULL, status);
 }

 bool _upb_DefPool_LoadDefInitEx(upb_DefPool* s, const _upb_DefPool_Init* init,
                                 bool rebuild_minitable) {
   /* Since this function should never fail (it would indicate a bug in upb) we
    * print errors to stderr instead of returning error status to the user. */
   _upb_DefPool_Init** deps = init->deps;
   UPB_DESC(FileDescriptorProto) * file;
   upb_Arena* arena;
   upb_Status status;

   upb_Status_Clear(&status);

   if (upb_DefPool_FindFileByName(s, init->filename)) {
     return true;
   }

   arena = upb_Arena_New();

   for (; *deps; deps++) {
     if (!_upb_DefPool_LoadDefInitEx(s, *deps, rebuild_minitable)) goto err;
   }

   file = UPB_DESC(FileDescriptorProto_parse_ex)(
       init->descriptor.data, init->descriptor.size, NULL,
       kUpb_DecodeOption_AliasString, arena);
   s->bytes_loaded += init->descriptor.size;

   if (!file) {
     upb_Status_SetErrorFormat(
         &status,
         "Failed to parse compiled-in descriptor for file '%s'. This should "
         "never happen.",
         init->filename);
     goto err;
   }

   const upb_MiniTableFile* mt = rebuild_minitable ? NULL : init->layout;
   if (!_upb_DefPool_AddFile(s, file, mt, &status)) {
     goto err;
   }

   upb_Arena_Free(arena);
   return true;

 err:
   fprintf(stderr,
           "Error loading compiled-in descriptor for file '%s' (this should "
           "never happen): %s\n",
           init->filename, upb_Status_ErrorMessage(&status));
   upb_Arena_Free(arena);
   return false;
 }

 size_t _upb_DefPool_BytesLoaded(const upb_DefPool* s) {
   return s->bytes_loaded;
 }

 upb_Arena* _upb_DefPool_Arena(const upb_DefPool* s) { return s->arena; }

 const upb_FieldDef* upb_DefPool_FindExtensionByMiniTable(
     const upb_DefPool* s, const upb_MiniTableExtension* ext) {
   upb_value v;
   bool ok = upb_inttable_lookup(&s->exts, (uintptr_t)ext, &v);
   UPB_ASSERT(ok);
   return upb_value_getconstptr(v);
 }

 const upb_FieldDef* upb_DefPool_FindExtensionByNumber(const upb_DefPool* s,
                                                       const upb_MessageDef* m,
                                                       int32_t fieldnum) {
   const upb_MiniTable* t = upb_MessageDef_MiniTable(m);
   const upb_MiniTableExtension* ext =
       upb_ExtensionRegistry_Lookup(s->extreg, t, fieldnum);
   return ext ? upb_DefPool_FindExtensionByMiniTable(s, ext) : NULL;
 }

 const upb_ExtensionRegistry* upb_DefPool_ExtensionRegistry(
     const upb_DefPool* s) {
   return s->extreg;
 }

 const upb_FieldDef** upb_DefPool_GetAllExtensions(const upb_DefPool* s,
                                                   const upb_MessageDef* m,
                                                   size_t* count) {
   size_t n = 0;
   intptr_t iter = UPB_INTTABLE_BEGIN;
   uintptr_t key;
   upb_value val;
   // This is O(all exts) instead of O(exts for m).  If we need this to be
   // efficient we may need to make extreg into a two-level table, or have a
   // second per-message index.
   while (upb_inttable_next(&s->exts, &key, &val, &iter)) {
     const upb_FieldDef* f = upb_value_getconstptr(val);
     if (upb_FieldDef_ContainingType(f) == m) n++;
   }
   const upb_FieldDef** exts = upb_gmalloc(n * sizeof(*exts));
   iter = UPB_INTTABLE_BEGIN;
   size_t i = 0;
   while (upb_inttable_next(&s->exts, &key, &val, &iter)) {
     const upb_FieldDef* f = upb_value_getconstptr(val);
     if (upb_FieldDef_ContainingType(f) == m) exts[i++] = f;
   }
   *count = n;
   return exts;
 }

 bool _upb_DefPool_LoadDefInit(upb_DefPool* s, const _upb_DefPool_Init* init) {
   return _upb_DefPool_LoadDefInitEx(s, init, false);
 }
	// Protocol Buffers - Google's data interchange format
	// Copyright 2023 Google LLC. All rights reserved.
	//
	// Use of this source code is governed by a BSD-style
	// license that can be found in the LICENSE file or at
	// https://developers.google.com/open-source/licenses/bsd

	#include "upb/reflection/internal/def_pool.h"

	#include "upb/base/status.h"
	#include "upb/hash/int_table.h"
	#include "upb/hash/str_table.h"
	#include "upb/mem/alloc.h"
	#include "upb/mem/arena.h"
	#include "upb/reflection/def_type.h"
	#include "upb/reflection/file_def.h"
	#include "upb/reflection/internal/def_builder.h"
	#include "upb/reflection/internal/enum_def.h"
	#include "upb/reflection/internal/enum_value_def.h"
	#include "upb/reflection/internal/field_def.h"
	#include "upb/reflection/internal/file_def.h"
	#include "upb/reflection/internal/message_def.h"
	#include "upb/reflection/internal/service_def.h"
	#include "upb/reflection/internal/upb_edition_defaults.h"

	// Must be last.
	#include "upb/port/def.inc"

	struct upb_DefPool {
	upb_Arena* arena;
	upb_strtable syms; // full_name -> packed def ptr
	upb_strtable files; // file_name -> (upb_FileDef*)
	upb_inttable exts; // (upb_MiniTableExtension) -> (upb_FieldDef)
	upb_ExtensionRegistry* extreg;
	const UPB_DESC(FeatureSetDefaults) * feature_set_defaults;
	upb_MiniTablePlatform platform;
	void* scratch_data;
	size_t scratch_size;
	size_t bytes_loaded;
	};

	void upb_DefPool_Free(upb_DefPool* s) {
	upb_Arena_Free(s->arena);
	upb_gfree(s->scratch_data);
	upb_gfree(s);
	}

	static const char serialized_defaults[] = UPB_INTERNAL_UPB_EDITION_DEFAULTS;

	upb_DefPool* upb_DefPool_New(void) {
	upb_DefPool* s = upb_gmalloc(sizeof(*s));
	if (!s) return NULL;

	s->arena = upb_Arena_New();
	s->bytes_loaded = 0;

	s->scratch_size = 240;
	s->scratch_data = upb_gmalloc(s->scratch_size);
	if (!s->scratch_data) goto err;

	if (!upb_strtable_init(&s->syms, 32, s->arena)) goto err;
	if (!upb_strtable_init(&s->files, 4, s->arena)) goto err;
	if (!upb_inttable_init(&s->exts, s->arena)) goto err;

	s->extreg = upb_ExtensionRegistry_New(s->arena);
	if (!s->extreg) goto err;

	s->platform = kUpb_MiniTablePlatform_Native;

	upb_Status status;
	if (!upb_DefPool_SetFeatureSetDefaults(
	s, serialized_defaults, sizeof(serialized_defaults) - 1, &status)) {
	goto err;
	}

	if (!s->feature_set_defaults) goto err;

	return s;

	err:
	upb_DefPool_Free(s);
	return NULL;
	}

	const UPB_DESC(FeatureSetDefaults) *
	upb_DefPool_FeatureSetDefaults(const upb_DefPool* s) {
	return s->feature_set_defaults;
	}

	bool upb_DefPool_SetFeatureSetDefaults(upb_DefPool* s,
	const char* serialized_defaults,
	size_t serialized_len,
	upb_Status* status) {
	const UPB_DESC(FeatureSetDefaults)* defaults = UPB_DESC(
	FeatureSetDefaults_parse)(serialized_defaults, serialized_len, s->arena);
	if (!defaults) {
	upb_Status_SetErrorFormat(status, "Failed to parse defaults");
	return false;
	}
	if (upb_strtable_count(&s->files) > 0) {
	upb_Status_SetErrorFormat(status,
	"Feature set defaults can't be changed once the "
	"pool has started building");
	return false;
	}
	int min_edition = UPB_DESC(FeatureSetDefaults_minimum_edition(defaults));
	int max_edition = UPB_DESC(FeatureSetDefaults_maximum_edition(defaults));
	if (min_edition > max_edition) {
	upb_Status_SetErrorFormat(status, "Invalid edition range %s to %s",
	upb_FileDef_EditionName(min_edition),
	upb_FileDef_EditionName(max_edition));
	return false;
	}
	size_t size;
	const UPB_DESC(
	FeatureSetDefaults_FeatureSetEditionDefault)* const* default_list =
	UPB_DESC(FeatureSetDefaults_defaults(defaults, &size));
	int prev_edition = UPB_DESC(EDITION_UNKNOWN);
	for (size_t i = 0; i < size; ++i) {
	int edition = UPB_DESC(
	FeatureSetDefaults_FeatureSetEditionDefault_edition(default_list[i]));
	if (edition == UPB_DESC(EDITION_UNKNOWN)) {
	upb_Status_SetErrorFormat(status, "Invalid edition UNKNOWN specified");
	return false;
	}
	if (edition <= prev_edition) {
	upb_Status_SetErrorFormat(status,
	"Feature set defaults are not strictly "
	"increasing, %s is greater than or equal to %s",
	upb_FileDef_EditionName(prev_edition),
	upb_FileDef_EditionName(edition));
	return false;
	}
	prev_edition = edition;
	}

	// Copy the defaults into the pool.
	s->feature_set_defaults = defaults;
	return true;
	}

	bool _upb_DefPool_InsertExt(upb_DefPool* s, const upb_MiniTableExtension* ext,
	const upb_FieldDef* f) {
	return upb_inttable_insert(&s->exts, (uintptr_t)ext, upb_value_constptr(f),
	s->arena);
	}

	bool _upb_DefPool_InsertSym(upb_DefPool* s, upb_StringView sym, upb_value v,
	upb_Status* status) {
	// TODO: table should support an operation "tryinsert" to avoid the double
	// lookup.
	if (upb_strtable_lookup2(&s->syms, sym.data, sym.size, NULL)) {
	upb_Status_SetErrorFormat(status, "duplicate symbol '%s'", sym.data);
	return false;
	}
	if (!upb_strtable_insert(&s->syms, sym.data, sym.size, v, s->arena)) {
	upb_Status_SetErrorMessage(status, "out of memory");
	return false;
	}
	return true;
	}

	static const void* _upb_DefPool_Unpack(const upb_DefPool* s, const char* sym,
	size_t size, upb_deftype_t type) {
	upb_value v;
	return upb_strtable_lookup2(&s->syms, sym, size, &v)
	? _upb_DefType_Unpack(v, type)
	: NULL;
	}

	bool _upb_DefPool_LookupSym(const upb_DefPool* s, const char* sym, size_t size,
	upb_value* v) {
	return upb_strtable_lookup2(&s->syms, sym, size, v);
	}

	upb_ExtensionRegistry* _upb_DefPool_ExtReg(const upb_DefPool* s) {
	return s->extreg;
	}

	void** _upb_DefPool_ScratchData(const upb_DefPool* s) {
	return (void**)&s->scratch_data;
	}

	size_t* _upb_DefPool_ScratchSize(const upb_DefPool* s) {
	return (size_t*)&s->scratch_size;
	}

	void _upb_DefPool_SetPlatform(upb_DefPool* s, upb_MiniTablePlatform platform) {
	assert(upb_strtable_count(&s->files) == 0);
	s->platform = platform;
	}

	const upb_MessageDef* upb_DefPool_FindMessageByName(const upb_DefPool* s,
	const char* sym) {
	return _upb_DefPool_Unpack(s, sym, strlen(sym), UPB_DEFTYPE_MSG);
	}

	const upb_MessageDef* upb_DefPool_FindMessageByNameWithSize(
	const upb_DefPool* s, const char* sym, size_t len) {
	return _upb_DefPool_Unpack(s, sym, len, UPB_DEFTYPE_MSG);
	}

	const upb_EnumDef* upb_DefPool_FindEnumByName(const upb_DefPool* s,
	const char* sym) {
	return _upb_DefPool_Unpack(s, sym, strlen(sym), UPB_DEFTYPE_ENUM);
	}

	const upb_EnumValueDef* upb_DefPool_FindEnumByNameval(const upb_DefPool* s,
	const char* sym) {
	return _upb_DefPool_Unpack(s, sym, strlen(sym), UPB_DEFTYPE_ENUMVAL);
	}

	const upb_FileDef* upb_DefPool_FindFileByName(const upb_DefPool* s,
	const char* name) {
	upb_value v;
	return upb_strtable_lookup(&s->files, name, &v) ? upb_value_getconstptr(v)
	: NULL;
	}

	const upb_FileDef* upb_DefPool_FindFileByNameWithSize(const upb_DefPool* s,
	const char* name,
	size_t len) {
	upb_value v;
	return upb_strtable_lookup2(&s->files, name, len, &v)
	? upb_value_getconstptr(v)
	: NULL;
	}

	const upb_FieldDef* upb_DefPool_FindExtensionByNameWithSize(
	const upb_DefPool* s, const char* name, size_t size) {
	upb_value v;
	if (!upb_strtable_lookup2(&s->syms, name, size, &v)) return NULL;

	switch (_upb_DefType_Type(v)) {
	case UPB_DEFTYPE_FIELD:
	return _upb_DefType_Unpack(v, UPB_DEFTYPE_FIELD);
	case UPB_DEFTYPE_MSG: {
	const upb_MessageDef* m = _upb_DefType_Unpack(v, UPB_DEFTYPE_MSG);
	return _upb_MessageDef_InMessageSet(m)
	? upb_MessageDef_NestedExtension(m, 0)
	: NULL;
	}
	default:
	break;
	}

	return NULL;
	}

	const upb_FieldDef* upb_DefPool_FindExtensionByName(const upb_DefPool* s,
	const char* sym) {
	return upb_DefPool_FindExtensionByNameWithSize(s, sym, strlen(sym));
	}

	const upb_ServiceDef* upb_DefPool_FindServiceByName(const upb_DefPool* s,
	const char* name) {
	return _upb_DefPool_Unpack(s, name, strlen(name), UPB_DEFTYPE_SERVICE);
	}

	const upb_ServiceDef* upb_DefPool_FindServiceByNameWithSize(
	const upb_DefPool* s, const char* name, size_t size) {
	return _upb_DefPool_Unpack(s, name, size, UPB_DEFTYPE_SERVICE);
	}

	const upb_FileDef* upb_DefPool_FindFileContainingSymbol(const upb_DefPool* s,
	const char* name) {
	upb_value v;
	// TODO: non-extension fields and oneofs.
	if (upb_strtable_lookup(&s->syms, name, &v)) {
	switch (_upb_DefType_Type(v)) {
	case UPB_DEFTYPE_EXT: {
	const upb_FieldDef* f = _upb_DefType_Unpack(v, UPB_DEFTYPE_EXT);
	return upb_FieldDef_File(f);
	}
	case UPB_DEFTYPE_MSG: {
	const upb_MessageDef* m = _upb_DefType_Unpack(v, UPB_DEFTYPE_MSG);
	return upb_MessageDef_File(m);
	}
	case UPB_DEFTYPE_ENUM: {
	const upb_EnumDef* e = _upb_DefType_Unpack(v, UPB_DEFTYPE_ENUM);
	return upb_EnumDef_File(e);
	}
	case UPB_DEFTYPE_ENUMVAL: {
	const upb_EnumValueDef* ev =
	_upb_DefType_Unpack(v, UPB_DEFTYPE_ENUMVAL);
	return upb_EnumDef_File(upb_EnumValueDef_Enum(ev));
	}
	case UPB_DEFTYPE_SERVICE: {
	const upb_ServiceDef* service =
	_upb_DefType_Unpack(v, UPB_DEFTYPE_SERVICE);
	return upb_ServiceDef_File(service);
	}
	default:
	UPB_UNREACHABLE();
	}
	}

	const char* last_dot = strrchr(name, '.');
	if (last_dot) {
	const upb_MessageDef* parent =
	upb_DefPool_FindMessageByNameWithSize(s, name, last_dot - name);
	if (parent) {
	const char* shortname = last_dot + 1;
	if (upb_MessageDef_FindByNameWithSize(parent, shortname,
	strlen(shortname), NULL, NULL)) {
	return upb_MessageDef_File(parent);
	}
	}
	}

	return NULL;
	}

	static void remove_filedef(upb_DefPool* s, upb_FileDef* file) {
	intptr_t iter = UPB_INTTABLE_BEGIN;
	upb_StringView key;
	upb_value val;
	while (upb_strtable_next2(&s->syms, &key, &val, &iter)) {
	const upb_FileDef* f;
	switch (_upb_DefType_Type(val)) {
	case UPB_DEFTYPE_EXT:
	f = upb_FieldDef_File(_upb_DefType_Unpack(val, UPB_DEFTYPE_EXT));
	break;
	case UPB_DEFTYPE_MSG:
	f = upb_MessageDef_File(_upb_DefType_Unpack(val, UPB_DEFTYPE_MSG));
	break;
	case UPB_DEFTYPE_ENUM:
	f = upb_EnumDef_File(_upb_DefType_Unpack(val, UPB_DEFTYPE_ENUM));
	break;
	case UPB_DEFTYPE_ENUMVAL:
	f = upb_EnumDef_File(upb_EnumValueDef_Enum(
	_upb_DefType_Unpack(val, UPB_DEFTYPE_ENUMVAL)));
	break;
	case UPB_DEFTYPE_SERVICE:
	f = upb_ServiceDef_File(_upb_DefType_Unpack(val, UPB_DEFTYPE_SERVICE));
	break;
	default:
	UPB_UNREACHABLE();
	}

	if (f == file) upb_strtable_removeiter(&s->syms, &iter);
	}
	}

	static const upb_FileDef* upb_DefBuilder_AddFileToPool(
	upb_DefBuilder* const builder, upb_DefPool* const s,
	const UPB_DESC(FileDescriptorProto) * const file_proto,
	const upb_StringView name, upb_Status* const status) {
	if (UPB_SETJMP(builder->err) != 0) {
	UPB_ASSERT(!upb_Status_IsOk(status));
	if (builder->file) {
	remove_filedef(s, builder->file);
	builder->file = NULL;
	}
	} else if (!builder->arena \|\| !builder->tmp_arena \|\|
	!upb_strtable_init(&builder->feature_cache, 16,
	builder->tmp_arena) \|\|
	!(builder->legacy_features =
	UPB_DESC(FeatureSet_new)(builder->tmp_arena))) {
	_upb_DefBuilder_OomErr(builder);
	} else {
	_upb_FileDef_Create(builder, file_proto);
	upb_strtable_insert(&s->files, name.data, name.size,
	upb_value_constptr(builder->file), builder->arena);
	UPB_ASSERT(upb_Status_IsOk(status));
	upb_Arena_Fuse(s->arena, builder->arena);
	}

	if (builder->arena) upb_Arena_Free(builder->arena);
	if (builder->tmp_arena) upb_Arena_Free(builder->tmp_arena);
	return builder->file;
	}

	static const upb_FileDef* _upb_DefPool_AddFile(
	upb_DefPool* s, const UPB_DESC(FileDescriptorProto) * file_proto,
	const upb_MiniTableFile* layout, upb_Status* status) {
	const upb_StringView name = UPB_DESC(FileDescriptorProto_name)(file_proto);

	// Determine whether we already know about this file.
	{
	upb_value v;
	if (upb_strtable_lookup2(&s->files, name.data, name.size, &v)) {
	upb_Status_SetErrorFormat(status,
	"duplicate file name " UPB_STRINGVIEW_FORMAT,
	UPB_STRINGVIEW_ARGS(name));
	return NULL;
	}
	}

	upb_DefBuilder ctx = {
	.symtab = s,
	.tmp_buf = NULL,
	.tmp_buf_size = 0,
	.layout = layout,
	.platform = s->platform,
	.msg_count = 0,
	.enum_count = 0,
	.ext_count = 0,
	.status = status,
	.file = NULL,
	.arena = upb_Arena_New(),
	.tmp_arena = upb_Arena_New(),
	};

	return upb_DefBuilder_AddFileToPool(&ctx, s, file_proto, name, status);
	}

	const upb_FileDef* upb_DefPool_AddFile(upb_DefPool* s,
	const UPB_DESC(FileDescriptorProto) *
	file_proto,
	upb_Status* status) {
	return _upb_DefPool_AddFile(s, file_proto, NULL, status);
	}

	bool _upb_DefPool_LoadDefInitEx(upb_DefPool* s, const _upb_DefPool_Init* init,
	bool rebuild_minitable) {
	/* Since this function should never fail (it would indicate a bug in upb) we
	* print errors to stderr instead of returning error status to the user. */
	_upb_DefPool_Init** deps = init->deps;
	UPB_DESC(FileDescriptorProto) * file;
	upb_Arena* arena;
	upb_Status status;

	upb_Status_Clear(&status);

	if (upb_DefPool_FindFileByName(s, init->filename)) {
	return true;
	}

	arena = upb_Arena_New();

	for (; *deps; deps++) {
	if (!_upb_DefPool_LoadDefInitEx(s, *deps, rebuild_minitable)) goto err;
	}

	file = UPB_DESC(FileDescriptorProto_parse_ex)(
	init->descriptor.data, init->descriptor.size, NULL,
	kUpb_DecodeOption_AliasString, arena);
	s->bytes_loaded += init->descriptor.size;

	if (!file) {
	upb_Status_SetErrorFormat(
	&status,
	"Failed to parse compiled-in descriptor for file '%s'. This should "
	"never happen.",
	init->filename);
	goto err;
	}

	const upb_MiniTableFile* mt = rebuild_minitable ? NULL : init->layout;
	if (!_upb_DefPool_AddFile(s, file, mt, &status)) {
	goto err;
	}

	upb_Arena_Free(arena);
	return true;

	err:
	fprintf(stderr,
	"Error loading compiled-in descriptor for file '%s' (this should "
	"never happen): %s\n",
	init->filename, upb_Status_ErrorMessage(&status));
	upb_Arena_Free(arena);
	return false;
	}

	size_t _upb_DefPool_BytesLoaded(const upb_DefPool* s) {
	return s->bytes_loaded;
	}

	upb_Arena* _upb_DefPool_Arena(const upb_DefPool* s) { return s->arena; }

	const upb_FieldDef* upb_DefPool_FindExtensionByMiniTable(
	const upb_DefPool* s, const upb_MiniTableExtension* ext) {
	upb_value v;
	bool ok = upb_inttable_lookup(&s->exts, (uintptr_t)ext, &v);
	UPB_ASSERT(ok);
	return upb_value_getconstptr(v);
	}

	const upb_FieldDef* upb_DefPool_FindExtensionByNumber(const upb_DefPool* s,
	const upb_MessageDef* m,
	int32_t fieldnum) {
	const upb_MiniTable* t = upb_MessageDef_MiniTable(m);
	const upb_MiniTableExtension* ext =
	upb_ExtensionRegistry_Lookup(s->extreg, t, fieldnum);
	return ext ? upb_DefPool_FindExtensionByMiniTable(s, ext) : NULL;
	}

	const upb_ExtensionRegistry* upb_DefPool_ExtensionRegistry(
	const upb_DefPool* s) {
	return s->extreg;
	}

	const upb_FieldDef** upb_DefPool_GetAllExtensions(const upb_DefPool* s,
	const upb_MessageDef* m,
	size_t* count) {
	size_t n = 0;
	intptr_t iter = UPB_INTTABLE_BEGIN;
	uintptr_t key;
	upb_value val;
	// This is O(all exts) instead of O(exts for m). If we need this to be
	// efficient we may need to make extreg into a two-level table, or have a
	// second per-message index.
	while (upb_inttable_next(&s->exts, &key, &val, &iter)) {
	const upb_FieldDef* f = upb_value_getconstptr(val);
	if (upb_FieldDef_ContainingType(f) == m) n++;
	}
	const upb_FieldDef** exts = upb_gmalloc(n * sizeof(*exts));
	iter = UPB_INTTABLE_BEGIN;
	size_t i = 0;
	while (upb_inttable_next(&s->exts, &key, &val, &iter)) {
	const upb_FieldDef* f = upb_value_getconstptr(val);
	if (upb_FieldDef_ContainingType(f) == m) exts[i++] = f;
	}
	*count = n;
	return exts;
	}

	bool _upb_DefPool_LoadDefInit(upb_DefPool* s, const _upb_DefPool_Init* init) {
	return _upb_DefPool_LoadDefInitEx(s, init, false);
	}