move (most of) the json code into its own subdir

Continuing the trend of giving individual build targets their own subdirs
where appropriate, and leaving behind temporary stub headers for compatibility.

JSON is a particularly good choice for this because of how little interaction
it has with the rest of upb.

PiperOrigin-RevId: 476792865
diff --git a/BUILD b/BUILD
index 43de536..fd16a0a 100644
--- a/BUILD
+++ b/BUILD
@@ -462,13 +462,17 @@
     ],
 )
 
+# TODO(b/232091617): Once we can delete the deprecated forwarding headers
+# (= everything in upb/) we can move this build target down into json/
 cc_library(
     name = "json",
     srcs = [
-        "upb/json_decode.c",
-        "upb/json_encode.c",
+        "upb/json/decode.c",
+        "upb/json/encode.c",
     ],
     hdrs = [
+        "upb/json/decode.h",
+        "upb/json/encode.h",
         "upb/json_decode.h",
         "upb/json_encode.h",
     ],
@@ -558,7 +562,7 @@
 proto_library(
     name = "json_test_proto",
     testonly = 1,
-    srcs = ["upb/json_test.proto"],
+    srcs = ["upb/json/test.proto"],
     deps = ["@com_google_protobuf//:struct_proto"],
 )
 
@@ -576,7 +580,7 @@
 
 cc_test(
     name = "json_decode_test",
-    srcs = ["upb/json_decode_test.cc"],
+    srcs = ["upb/json/decode_test.cc"],
     deps = [
         ":json",
         ":json_test_upb_proto",
@@ -590,7 +594,7 @@
 
 cc_test(
     name = "json_encode_test",
-    srcs = ["upb/json_encode_test.cc"],
+    srcs = ["upb/json/encode_test.cc"],
     deps = [
         ":json",
         ":json_test_upb_proto",
diff --git a/upb/bindings/lua/msg.c b/upb/bindings/lua/msg.c
index 4e37e0c..9ffb92d 100644
--- a/upb/bindings/lua/msg.c
+++ b/upb/bindings/lua/msg.c
@@ -39,8 +39,8 @@
 
 #include "lauxlib.h"
 #include "upb/bindings/lua/upb.h"
-#include "upb/json_decode.h"
-#include "upb/json_encode.h"
+#include "upb/json/decode.h"
+#include "upb/json/encode.h"
 #include "upb/map.h"
 #include "upb/port_def.inc"
 #include "upb/reflection/message.h"
diff --git a/upb/conformance_upb.c b/upb/conformance_upb.c
index b08239b..d6a3e1e 100644
--- a/upb/conformance_upb.c
+++ b/upb/conformance_upb.c
@@ -41,8 +41,8 @@
 #include "google/protobuf/test_messages_proto3.upbdefs.h"
 #include "upb/decode.h"
 #include "upb/encode.h"
-#include "upb/json_decode.h"
-#include "upb/json_encode.h"
+#include "upb/json/decode.h"
+#include "upb/json/encode.h"
 #include "upb/reflection/message.h"
 #include "upb/text_encode.h"
 
diff --git a/upb/json_decode.c b/upb/json/decode.c
similarity index 99%
rename from upb/json_decode.c
rename to upb/json/decode.c
index 2342d68..d07362e 100644
--- a/upb/json_decode.c
+++ b/upb/json/decode.c
@@ -25,7 +25,7 @@
  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
-#include "upb/json_decode.h"
+#include "upb/json/decode.h"
 
 #include <errno.h>
 #include <float.h>
diff --git a/upb/json/decode.h b/upb/json/decode.h
new file mode 100644
index 0000000..5ddb164
--- /dev/null
+++ b/upb/json/decode.h
@@ -0,0 +1,52 @@
+/*
+ * Copyright (c) 2009-2021, Google LLC
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *     * Redistributions of source code must retain the above copyright
+ *       notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above copyright
+ *       notice, this list of conditions and the following disclaimer in the
+ *       documentation and/or other materials provided with the distribution.
+ *     * Neither the name of Google LLC nor the
+ *       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
+ * (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
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef UPB_JSON_DECODE_H_
+#define UPB_JSON_DECODE_H_
+
+#include "upb/reflection/def.h"
+
+// Must be last.
+#include "upb/port_def.inc"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+enum { upb_JsonDecode_IgnoreUnknown = 1 };
+
+bool upb_JsonDecode(const char* buf, size_t size, upb_Message* msg,
+                    const upb_MessageDef* m, const upb_DefPool* symtab,
+                    int options, upb_Arena* arena, upb_Status* status);
+
+#ifdef __cplusplus
+} /* extern "C" */
+#endif
+
+#include "upb/port_undef.inc"
+
+#endif /* UPB_JSONDECODE_H_ */
diff --git a/upb/json_decode_test.cc b/upb/json/decode_test.cc
similarity index 96%
rename from upb/json_decode_test.cc
rename to upb/json/decode_test.cc
index 2d41e60..deb40f4 100644
--- a/upb/json_decode_test.cc
+++ b/upb/json/decode_test.cc
@@ -25,14 +25,12 @@
  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
-#include "upb/json_decode.h"
-
-#include <stdio.h>
+#include "upb/json/decode.h"
 
 #include "google/protobuf/struct.upb.h"
 #include "gtest/gtest.h"
-#include "upb/json_test.upb.h"
-#include "upb/json_test.upbdefs.h"
+#include "upb/json/test.upb.h"
+#include "upb/json/test.upbdefs.h"
 #include "upb/reflection/def.hpp"
 #include "upb/upb.hpp"
 
diff --git a/upb/json_encode.c b/upb/json/encode.c
similarity index 99%
rename from upb/json_encode.c
rename to upb/json/encode.c
index 487ee11..c833087 100644
--- a/upb/json_encode.c
+++ b/upb/json/encode.c
@@ -25,7 +25,7 @@
  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
-#include "upb/json_encode.h"
+#include "upb/json/encode.h"
 
 #include <ctype.h>
 #include <float.h>
diff --git a/upb/json/encode.h b/upb/json/encode.h
new file mode 100644
index 0000000..95fcca7
--- /dev/null
+++ b/upb/json/encode.h
@@ -0,0 +1,70 @@
+/*
+ * Copyright (c) 2009-2021, Google LLC
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *     * Redistributions of source code must retain the above copyright
+ *       notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above copyright
+ *       notice, this list of conditions and the following disclaimer in the
+ *       documentation and/or other materials provided with the distribution.
+ *     * Neither the name of Google LLC nor the
+ *       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
+ * (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
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef UPB_JSON_ENCODE_H_
+#define UPB_JSON_ENCODE_H_
+
+#include "upb/reflection/def.h"
+
+// Must be last.
+#include "upb/port_def.inc"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+enum {
+  /* When set, emits 0/default values.  TODO(haberman): proto3 only? */
+  upb_JsonEncode_EmitDefaults = 1 << 0,
+
+  /* When set, use normal (snake_case) field names instead of JSON (camelCase)
+     names. */
+  upb_JsonEncode_UseProtoNames = 1 << 1,
+
+  /* When set, emits enums as their integer values instead of as their names. */
+  upb_JsonEncode_FormatEnumsAsIntegers = 1 << 2
+};
+
+/* Encodes the given |msg| to JSON format.  The message's reflection is given in
+ * |m|.  The symtab in |symtab| is used to find extensions (if NULL, extensions
+ * will not be printed).
+ *
+ * Output is placed in the given buffer, and always NULL-terminated.  The output
+ * size (excluding NULL) is returned.  This means that a return value >= |size|
+ * implies that the output was truncated.  (These are the same semantics as
+ * snprintf()). */
+size_t upb_JsonEncode(const upb_Message* msg, const upb_MessageDef* m,
+                      const upb_DefPool* ext_pool, int options, char* buf,
+                      size_t size, upb_Status* status);
+
+#ifdef __cplusplus
+} /* extern "C" */
+#endif
+
+#include "upb/port_undef.inc"
+
+#endif /* UPB_JSONENCODE_H_ */
diff --git a/upb/json_encode_test.cc b/upb/json/encode_test.cc
similarity index 97%
rename from upb/json_encode_test.cc
rename to upb/json/encode_test.cc
index 0d14b41..4c0d1a7 100644
--- a/upb/json_encode_test.cc
+++ b/upb/json/encode_test.cc
@@ -25,12 +25,12 @@
  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
-#include "upb/json_encode.h"
+#include "upb/json/encode.h"
 
 #include "google/protobuf/struct.upb.h"
 #include "gtest/gtest.h"
-#include "upb/json_test.upb.h"
-#include "upb/json_test.upbdefs.h"
+#include "upb/json/test.upb.h"
+#include "upb/json/test.upbdefs.h"
 #include "upb/reflection/def.hpp"
 #include "upb/upb.hpp"
 
diff --git a/upb/json_test.proto b/upb/json/test.proto
similarity index 100%
rename from upb/json_test.proto
rename to upb/json/test.proto
diff --git a/upb/json_decode.h b/upb/json_decode.h
index a5abad2..c27c91b 100644
--- a/upb/json_decode.h
+++ b/upb/json_decode.h
@@ -25,28 +25,11 @@
  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
+// This header is deprecated, use upb/json/decode.h instead
+
 #ifndef UPB_JSONDECODE_H_
 #define UPB_JSONDECODE_H_
 
-#include "upb/reflection/def.h"
-
-// Must be last.
-#include "upb/port_def.inc"
-
-#ifdef __cplusplus
-extern "C" {
-#endif
-
-enum { upb_JsonDecode_IgnoreUnknown = 1 };
-
-bool upb_JsonDecode(const char* buf, size_t size, upb_Message* msg,
-                    const upb_MessageDef* m, const upb_DefPool* symtab,
-                    int options, upb_Arena* arena, upb_Status* status);
-
-#ifdef __cplusplus
-} /* extern "C" */
-#endif
-
-#include "upb/port_undef.inc"
+#include "upb/json/decode.h"
 
 #endif /* UPB_JSONDECODE_H_ */
diff --git a/upb/json_encode.h b/upb/json_encode.h
index b2207a9..e76e138 100644
--- a/upb/json_encode.h
+++ b/upb/json_encode.h
@@ -25,46 +25,11 @@
  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
+// This header is deprecated, use upb/json/encode.h instead
+
 #ifndef UPB_JSONENCODE_H_
 #define UPB_JSONENCODE_H_
 
-#include "upb/reflection/def.h"
-
-// Must be last.
-#include "upb/port_def.inc"
-
-#ifdef __cplusplus
-extern "C" {
-#endif
-
-enum {
-  /* When set, emits 0/default values.  TODO(haberman): proto3 only? */
-  upb_JsonEncode_EmitDefaults = 1 << 0,
-
-  /* When set, use normal (snake_case) field names instead of JSON (camelCase)
-     names. */
-  upb_JsonEncode_UseProtoNames = 1 << 1,
-
-  /* When set, emits enums as their integer values instead of as their names. */
-  upb_JsonEncode_FormatEnumsAsIntegers = 1 << 2
-};
-
-/* Encodes the given |msg| to JSON format.  The message's reflection is given in
- * |m|.  The symtab in |symtab| is used to find extensions (if NULL, extensions
- * will not be printed).
- *
- * Output is placed in the given buffer, and always NULL-terminated.  The output
- * size (excluding NULL) is returned.  This means that a return value >= |size|
- * implies that the output was truncated.  (These are the same semantics as
- * snprintf()). */
-size_t upb_JsonEncode(const upb_Message* msg, const upb_MessageDef* m,
-                      const upb_DefPool* ext_pool, int options, char* buf,
-                      size_t size, upb_Status* status);
-
-#ifdef __cplusplus
-} /* extern "C" */
-#endif
-
-#include "upb/port_undef.inc"
+#include "upb/json/encode.h"
 
 #endif /* UPB_JSONENCODE_H_ */
diff --git a/upb/msg_test.cc b/upb/msg_test.cc
index 085a85a..055aed2 100644
--- a/upb/msg_test.cc
+++ b/upb/msg_test.cc
@@ -29,8 +29,8 @@
 #include "gtest/gtest.h"
 #include "google/protobuf/test_messages_proto3.upb.h"
 #include "upb/fuzz_test_util.h"
-#include "upb/json_decode.h"
-#include "upb/json_encode.h"
+#include "upb/json/decode.h"
+#include "upb/json/encode.h"
 #include "upb/msg_test.upb.h"
 #include "upb/msg_test.upbdefs.h"
 #include "upb/reflection/def.hpp"
diff --git a/upb/test_cpp.cc b/upb/test_cpp.cc
index e707714..b7101f6 100644
--- a/upb/test_cpp.cc
+++ b/upb/test_cpp.cc
@@ -38,8 +38,8 @@
 #include "google/protobuf/timestamp.upb.h"
 #include "google/protobuf/timestamp.upbdefs.h"
 #include "gtest/gtest.h"
-#include "upb/json_decode.h"
-#include "upb/json_encode.h"
+#include "upb/json/decode.h"
+#include "upb/json/encode.h"
 #include "upb/reflection/def.h"
 #include "upb/reflection/def.hpp"
 #include "upb/test_cpp.upb.h"
diff --git a/upbc/protoc-gen-upbdev.cc b/upbc/protoc-gen-upbdev.cc
index a320c89..ca79a40 100644
--- a/upbc/protoc-gen-upbdev.cc
+++ b/upbc/protoc-gen-upbdev.cc
@@ -30,8 +30,8 @@
 
 #include "google/protobuf/compiler/plugin.upb.h"
 #include "google/protobuf/compiler/plugin.upbdefs.h"
-#include "upb/json_decode.h"
-#include "upb/json_encode.h"
+#include "upb/json/decode.h"
+#include "upb/json/encode.h"
 #include "upb/reflection/def.h"
 #include "upb/upb.h"
 #include "upbc/code_generator_request.h"