iproto: replace iproto_constant with string arrays

locker · locker · commit 7563213316b4 · 2023-06-01T10:25:21.000+03:00
There are no substantial gaps in the remaining IPROTO constant enums so there's no need in iproto_constant struct. Instead we can generate string arrays, as we usually do. This is more flexible because it allows us to look up a name by code. It's also consistent with iproto_type and iproto_key names. The only tricky part here is the iproto_flag enum because it contains bit masks. To generate names for the flags, we add the auxiliary enum iproto_flag_bit that contains bit numbers. Follow-up tarantool#8443 Follow-up commit b3fb883 ("iproto: export IPROTO constants to Lua automatically") NO_DOC=refactoring NO_TEST=refactoring NO_CHANGELOG=refactoring
diff --git a/src/box/iproto_constants.c b/src/box/iproto_constants.c
@@ -52,11 +52,12 @@ const uint64_t iproto_body_key_map[IPROTO_TYPE_STAT_MAX] = {
 };
 #undef bit
 
-const struct iproto_constant iproto_flag_constants[] = {
-	IPROTO_FLAGS(IPROTO_CONSTANT_MEMBER)
-};
+#define IPROTO_FLAG_BIT_STRS_MEMBER(s, ...) \
+	[IPROTO_FLAG_BIT_ ## s] = #s,
 
-const size_t iproto_flag_constants_size = lengthof(iproto_flag_constants);
+const char *iproto_flag_bit_strs[iproto_flag_bit_MAX] = {
+	IPROTO_FLAGS(IPROTO_FLAG_BIT_STRS_MEMBER)
+};
 
 #define IPROTO_KEY_TYPE_MEMBER(s, v, t) \
 	[IPROTO_ ## s] = t,
@@ -72,33 +73,33 @@ const char *iproto_key_strs[iproto_key_MAX] = {
 	IPROTO_KEYS(IPROTO_KEY_STRS_MEMBER)
 };
 
-const struct iproto_constant iproto_metadata_key_constants[] = {
-	IPROTO_METADATA_KEYS(IPROTO_CONSTANT_MEMBER)
+#define IPROTO_METADATA_KEY_STRS_MEMBER(s, ...) \
+	[IPROTO_FIELD_ ## s] = #s,
+
+const char *iproto_metadata_key_strs[iproto_metadata_key_MAX] = {
+	IPROTO_METADATA_KEYS(IPROTO_METADATA_KEY_STRS_MEMBER)
 };
 
-const size_t iproto_metadata_key_constants_size =
-	lengthof(iproto_metadata_key_constants);
+#define IPROTO_BALLOT_KEY_STRS_MEMBER(s, ...) \
+	[IPROTO_BALLOT_ ## s] = #s,
 
-const struct iproto_constant iproto_ballot_key_constants[] = {
-	IPROTO_BALLOT_KEYS(IPROTO_CONSTANT_MEMBER)
+const char *iproto_ballot_key_strs[iproto_ballot_key_MAX] = {
+	IPROTO_BALLOT_KEYS(IPROTO_BALLOT_KEY_STRS_MEMBER)
 };
 
-const size_t iproto_ballot_key_constants_size =
-	lengthof(iproto_ballot_key_constants);
-
 #define IPROTO_TYPE_STRS_MEMBER(s, ...) \
 	[IPROTO_ ## s] = #s,
 
 const char *iproto_type_strs[iproto_type_MAX] = {
 	IPROTO_TYPES(IPROTO_TYPE_STRS_MEMBER)
 };
 
-const struct iproto_constant iproto_raft_keys_constants[] = {
-	IPROTO_RAFT_KEYS(IPROTO_CONSTANT_MEMBER)
-};
+#define IPROTO_RAFT_KEY_STRS_MEMBER(s, ...) \
+	[IPROTO_RAFT_ ## s] = #s,
 
-const size_t iproto_raft_keys_constants_size =
-	lengthof(iproto_raft_keys_constants);
+const char *iproto_raft_key_strs[iproto_raft_key_MAX] = {
+	IPROTO_RAFT_KEYS(IPROTO_RAFT_KEY_STRS_MEMBER)
+};
 
 #define VY_RUN_INFO_KEY_STRS_MEMBER(s, ...) \
 	[VY_RUN_INFO_ ## s] = #s,
diff --git a/src/box/iproto_constants.h b/src/box/iproto_constants.h
@@ -40,16 +40,6 @@
 extern "C" {
 #endif
 
-/** Named IPROTO constant. */
-struct iproto_constant {
-	/** NULL-terminated name of constant. */
-	const char *name;
-	/** Value of constant. */
-	int value;
-};
-
-#define IPROTO_CONSTANT_MEMBER(s, v, ...) {.name = #s, .value = v},
-
 enum {
 	/** Maximal iproto package body length (2GiB) */
 	IPROTO_BODY_LEN_MAX = 2147483648UL,
@@ -62,23 +52,27 @@ enum {
 /** IPROTO_FLAGS bitfield constants. */
 #define IPROTO_FLAGS(_)							\
 	/** Set for the last xrow in a transaction. */			\
-	_(COMMIT, 0x01)							\
+	_(COMMIT, 0)							\
 	/** Set for the last row of a tx residing in limbo. */		\
-	_(WAIT_SYNC, 0x02)						\
+	_(WAIT_SYNC, 1)							\
 	/** Set for the last row of a synchronous tx. */		\
-	_(WAIT_ACK, 0x04)						\
+	_(WAIT_ACK, 2)							\
 
-#define IPROTO_FLAG_MEMBER(s, v) IPROTO_FLAG_ ## s = v,
+#define IPROTO_FLAG_MEMBER(s, v) IPROTO_FLAG_ ## s = 1ULL << (v),
 
 enum iproto_flag {
 	IPROTO_FLAGS(IPROTO_FLAG_MEMBER)
 };
 
-/** Constants generated from IPROTO_FLAGS. */
-extern const struct iproto_constant iproto_flag_constants[];
+#define IPROTO_FLAG_BIT_MEMBER(s, v) IPROTO_FLAG_BIT_ ## s = v,
+
+enum iproto_flag_bit {
+	IPROTO_FLAGS(IPROTO_FLAG_BIT_MEMBER)
+	iproto_flag_bit_MAX,
+};
 
-/** Size of iproto_flag_constants. */
-extern const size_t iproto_flag_constants_size;
+/** IPROTO flag name by bit number. */
+extern const char *iproto_flag_bit_strs[];
 
 /**
  * IPROTO key name, code, and MsgPack value type.
@@ -253,13 +247,11 @@ extern const unsigned char iproto_key_type[];
 
 enum iproto_metadata_key {
 	IPROTO_METADATA_KEYS(IPROTO_METADATA_KEY_MEMBER)
+	iproto_metadata_key_MAX
 };
 
-/** Constants generated from IPROTO_METADATA_KEYS. */
-extern const struct iproto_constant iproto_metadata_key_constants[];
-
-/** Size of iproto_metadata_key_constants. */
-extern const size_t iproto_metadata_key_constants_size;
+/** IPROTO metadata key name by code */
+extern const char *iproto_metadata_key_strs[];
 
 #define IPROTO_BALLOT_KEYS(_)						\
 	_(IS_RO_CFG, 0x01)						\
@@ -276,13 +268,11 @@ extern const size_t iproto_metadata_key_constants_size;
 
 enum iproto_ballot_key {
 	IPROTO_BALLOT_KEYS(IPROTO_BALLOT_KEY_MEMBER)
+	iproto_ballot_key_MAX
 };
 
-/** Constants generated from IPROTO_BALLOT_KEYS. */
-extern const struct iproto_constant iproto_ballot_key_constants[];
-
-/** Size of iproto_ballot_key_constants. */
-extern const size_t iproto_ballot_key_constants_size;
+/** IPROTO ballot key name by code */
+extern const char *iproto_ballot_key_strs[];
 
 static inline uint64_t
 iproto_key_bit(unsigned char key)
@@ -432,13 +422,11 @@ extern const char *iproto_type_strs[];
 
 enum iproto_raft_key {
 	IPROTO_RAFT_KEYS(IPROTO_RAFT_KEY_MEMBER)
+	iproto_raft_key_MAX
 };
 
-/** Constants generated from IPROTO_RAFT_KEYS. */
-extern const struct iproto_constant iproto_raft_keys_constants[];
-
-/** Size of iproto_raft_keys_constants. */
-extern const size_t iproto_raft_keys_constants_size;
+/** IPROTO raft key name by code */
+extern const char *iproto_raft_key_strs[];
 
 /**
  * Returns IPROTO type name by @a type code.
diff --git a/src/box/iproto_features.c b/src/box/iproto_features.c
@@ -9,6 +9,13 @@
 
 #include "msgpuck.h"
 
+#define IPROTO_FEATURE_ID_STRS_MEMBER(s, ...) \
+	[IPROTO_FEATURE_ ## s] = #s,
+
+const char *iproto_feature_id_strs[iproto_feature_id_MAX] = {
+	IPROTO_FEATURES(IPROTO_FEATURE_ID_STRS_MEMBER)
+};
+
 struct iproto_features IPROTO_CURRENT_FEATURES;
 
 uint32_t
@@ -54,13 +61,6 @@ mp_decode_iproto_features(const char **data, struct iproto_features *features)
 	return 0;
 }
 
-const struct iproto_constant iproto_feature_id_constants[] = {
-	IPROTO_FEATURES(IPROTO_CONSTANT_MEMBER)
-};
-
-const size_t iproto_feature_id_constants_size =
-	lengthof(iproto_feature_id_constants);
-
 void
 iproto_features_init(void)
 {
diff --git a/src/box/iproto_features.h b/src/box/iproto_features.h
@@ -10,7 +10,6 @@
 #include <string.h>
 
 #include "bit/bit.h"
-#include "iproto_constants.h"
 
 #if defined(__cplusplus)
 extern "C" {
@@ -66,11 +65,8 @@ enum iproto_feature_id {
 	iproto_feature_id_MAX
 };
 
-/** Constants generated from IPROTO_FEATURES. */
-extern const struct iproto_constant iproto_feature_id_constants[];
-
-/** Size of iproto_feature_id_constants. */
-extern const size_t iproto_feature_id_constants_size;
+/** IPROTO feature name by id. */
+extern const char *iproto_feature_id_strs[];
 
 /**
  * IPROTO protocol feature bit map.
diff --git a/src/box/lua/iproto.c b/src/box/lua/iproto.c
@@ -28,32 +28,18 @@
 
 struct mh_strnu32_t *iproto_key_translation;
 
-/**
- * Pushes an array of IPROTO constants onto Lua stack.
- */
-static void
-push_iproto_constant_subnamespace(struct lua_State *L, const char *subnamespace,
-				  const struct iproto_constant *constants,
-				  int constants_len)
-{
-	lua_createtable(L, 0, constants_len);
-	for (int i = 0; i < constants_len; ++i) {
-		const char *name = constants[i].name;
-		int value = constants[i].value;
-		lua_pushinteger(L, value);
-		lua_setfield(L, -2, name);
-	}
-	lua_setfield(L, -2, subnamespace);
-}
-
 /**
  * Pushes IPROTO constants generated from `IPROTO_FLAGS` onto Lua stack.
  */
 static void
-push_iproto_flag_constants(struct lua_State *L)
+push_iproto_flag_enum(struct lua_State *L)
 {
-	push_iproto_constant_subnamespace(L, "flag", iproto_flag_constants,
-					  iproto_flag_constants_size);
+	lua_newtable(L);
+	for (int i = 0; i < iproto_flag_bit_MAX; i++) {
+		lua_pushinteger(L, 1ULL << i);
+		lua_setfield(L, -2, iproto_flag_bit_strs[i]);
+	}
+	lua_setfield(L, -2, "flag");
 }
 
 /**
@@ -93,9 +79,13 @@ push_iproto_key_enum(struct lua_State *L)
 static void
 push_iproto_metadata_key_enum(struct lua_State *L)
 {
-	push_iproto_constant_subnamespace(L, "metadata_key",
-					  iproto_metadata_key_constants,
-					  iproto_metadata_key_constants_size);
+	lua_newtable(L);
+	for (int i = 0; i < iproto_metadata_key_MAX; i++) {
+		const char *name = iproto_metadata_key_strs[i];
+		lua_pushinteger(L, i);
+		lua_setfield(L, -2, name);
+	}
+	lua_setfield(L, -2, "metadata_key");
 }
 
 /**
@@ -104,9 +94,15 @@ push_iproto_metadata_key_enum(struct lua_State *L)
 static void
 push_iproto_ballot_key_enum(struct lua_State *L)
 {
-	push_iproto_constant_subnamespace(L, "ballot_key",
-					  iproto_ballot_key_constants,
-					  iproto_ballot_key_constants_size);
+	lua_newtable(L);
+	for (int i = 0; i < iproto_ballot_key_MAX; i++) {
+		const char *name = iproto_ballot_key_strs[i];
+		if (name == NULL)
+			continue;
+		lua_pushinteger(L, i);
+		lua_setfield(L, -2, name);
+	}
+	lua_setfield(L, -2, "ballot_key");
 }
 
 /**
@@ -136,9 +132,13 @@ push_iproto_type_enum(struct lua_State *L)
 static void
 push_iproto_raft_keys_enum(struct lua_State *L)
 {
-	push_iproto_constant_subnamespace(L, "raft_key",
-					  iproto_raft_keys_constants,
-					  iproto_raft_keys_constants_size);
+	lua_newtable(L);
+	for (int i = 0; i < iproto_raft_key_MAX; i++) {
+		const char *name = iproto_raft_key_strs[i];
+		lua_pushinteger(L, i);
+		lua_setfield(L, -2, name);
+	}
+	lua_setfield(L, -2, "raft_key");
 }
 
 /**
@@ -147,7 +147,7 @@ push_iproto_raft_keys_enum(struct lua_State *L)
 static void
 push_iproto_constants(struct lua_State *L)
 {
-	push_iproto_flag_constants(L);
+	push_iproto_flag_enum(L);
 	push_iproto_key_enum(L);
 	push_iproto_metadata_key_enum(L);
 	push_iproto_ballot_key_enum(L);
@@ -164,15 +164,13 @@ push_iproto_protocol_features(struct lua_State *L)
 	lua_pushinteger(L, IPROTO_CURRENT_VERSION);
 	lua_setfield(L, -2, "protocol_version");
 
-	for (size_t i = 0; i < 2; ++i)
-		lua_createtable(L, 0, iproto_feature_id_constants_size);
-	for (size_t i = 0; i < iproto_feature_id_constants_size; ++i) {
-		struct iproto_constant constant =
-			iproto_feature_id_constants[i];
-		char *name = strtolowerdup(constant.name);
+	for (int i = 0; i < 2; i++)
+		lua_newtable(L);
+	for (int i = 0; i < iproto_feature_id_MAX; i++) {
+		char *name = strtolowerdup(iproto_feature_id_strs[i]);
 		lua_pushboolean(L, true);
 		lua_setfield(L, -2, name);
-		lua_pushinteger(L, iproto_feature_id_constants[i].value);
+		lua_pushinteger(L, i);
 		lua_setfield(L, -3, name);
 		free(name);
 	}
