Initial implementation of C api (#915)

Implement a C interface to some of libswsscommon in support of sonic-dash-ha.

Related:
sonic-net/sonic-dash-ha#6
#921

Incoming follow up PR:
erer1243#1

---------

Co-authored-by: erer1243 <erer1243@users.noreply.github.com>

common/Makefile.am

@@ -68,7 +68,16 @@ common_libswsscommon_la_SOURCES = \
     common/zmqclient.cpp             \
     common/zmqserver.cpp             \
     common/asyncdbupdater.cpp        \
-    common/redis_table_waiter.cpp
+    common/redis_table_waiter.cpp    \
+    common/c-api/util.cpp                  \
+    common/c-api/dbconnector.cpp           \
+    common/c-api/consumerstatetable.cpp    \
+    common/c-api/producerstatetable.cpp    \
+    common/c-api/subscriberstatetable.cpp  \
+    common/c-api/zmqclient.cpp             \
+    common/c-api/zmqserver.cpp             \
+    common/c-api/zmqconsumerstatetable.cpp \
+    common/c-api/zmqproducerstatetable.cpp
 
 common_libswsscommon_la_CXXFLAGS = $(DBGFLAGS) $(AM_CFLAGS) $(CFLAGS_COMMON) $(LIBNL_CFLAGS) $(CODE_COVERAGE_CXXFLAGS)
 common_libswsscommon_la_CPPFLAGS = $(DBGFLAGS) $(AM_CFLAGS) $(CFLAGS_COMMON) $(LIBNL_CPPFLAGS) $(CODE_COVERAGE_CPPFLAGS)

common/binaryserializer.h

@@ -2,6 +2,8 @@
 #define __BINARY_SERIALIZER__
 
 #include "common/armhelper.h"
+#include "common/rediscommand.h"
+#include "common/table.h"
 
 #include <string>
 
@@ -11,6 +13,26 @@ namespace swss {
 
 class BinarySerializer {
 public:
+    static size_t serializedSize(const string &dbName, const string &tableName,
+                                 const vector<KeyOpFieldsValuesTuple> &kcos) {
+        size_t n = 0;
+        n += dbName.size() + sizeof(size_t);
+        n += tableName.size() + sizeof(size_t);
+
+        for (const KeyOpFieldsValuesTuple &kco : kcos) {
+            const vector<FieldValueTuple> &fvs = kfvFieldsValues(kco);
+            n += kfvKey(kco).size() + sizeof(size_t);
+            n += to_string(fvs.size()).size() + sizeof(size_t);
+
+            for (const FieldValueTuple &fv : fvs) {
+                n += fvField(fv).size() + sizeof(size_t);
+                n += fvValue(fv).size() + sizeof(size_t);
+            }
+        }
+
+        return n + sizeof(size_t);
+    }
+
     static size_t serializeBuffer(
         const char* buffer,
         const size_t size,
@@ -192,8 +214,8 @@ class BinarySerializer {
     {
         if ((size_t)(m_current_position - m_buffer + datalen + sizeof(size_t)) > m_buffer_size)
         {
-            SWSS_LOG_THROW("There are not enough buffer for binary serializer to serialize,\
-                             key count: %zu, data length %zu, buffer size: %zu",
+            SWSS_LOG_THROW("There are not enough buffer for binary serializer to serialize,\n"
+                           "  key count: %zu, data length %zu, buffer size: %zu",
                                                 m_kvp_count,
                                                 datalen,
                                                 m_buffer_size);

common/c-api/consumerstatetable.cpp

@@ -0,0 +1,34 @@
+#include <cstdlib>
+#include <cstring>
+#include <deque>
+
+#include "../consumerstatetable.h"
+#include "../dbconnector.h"
+#include "../table.h"
+#include "consumerstatetable.h"
+#include "util.h"
+
+using namespace swss;
+using namespace std;
+
+SWSSConsumerStateTable SWSSConsumerStateTable_new(SWSSDBConnector db, const char *tableName,
+                                                  const int32_t *p_popBatchSize,
+                                                  const int32_t *p_pri) {
+    int popBatchSize = p_popBatchSize ? numeric_cast<int>(*p_popBatchSize)
+                                      : TableConsumable::DEFAULT_POP_BATCH_SIZE;
+    int pri = p_pri ? numeric_cast<int>(*p_pri) : 0;
+    SWSSTry(return (SWSSConsumerStateTable) new ConsumerStateTable(
+        (DBConnector *)db, string(tableName), popBatchSize, pri));
+}
+
+void SWSSConsumerStateTable_free(SWSSConsumerStateTable tbl) {
+    SWSSTry(delete (ConsumerStateTable *)tbl);
+}
+
+SWSSKeyOpFieldValuesArray SWSSConsumerStateTable_pops(SWSSConsumerStateTable tbl) {
+    SWSSTry({
+        deque<KeyOpFieldsValuesTuple> vkco;
+        ((ConsumerStateTable *)tbl)->pops(vkco);
+        return makeKeyOpFieldValuesArray(vkco);
+    });
+}

common/c-api/consumerstatetable.h

@@ -0,0 +1,28 @@
+#ifndef SWSS_COMMON_C_API_CONSUMERSTATETABLE_H
+#define SWSS_COMMON_C_API_CONSUMERSTATETABLE_H
+
+#include "dbconnector.h"
+#include "util.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include <stdint.h>
+
+typedef struct SWSSConsumerStateTableOpaque *SWSSConsumerStateTable;
+
+// Pass NULL for popBatchSize and/or pri to use the default values
+SWSSConsumerStateTable SWSSConsumerStateTable_new(SWSSDBConnector db, const char *tableName,
+                                                  const int32_t *popBatchSize, const int32_t *pri);
+
+void SWSSConsumerStateTable_free(SWSSConsumerStateTable tbl);
+
+// Result array and all of its members must be freed using free()
+SWSSKeyOpFieldValuesArray SWSSConsumerStateTable_pops(SWSSConsumerStateTable tbl);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif

common/c-api/dbconnector.cpp

@@ -0,0 +1,84 @@
+#include <cstring>
+#include <string>
+
+#include "../dbconnector.h"
+#include "dbconnector.h"
+#include "util.h"
+
+using namespace swss;
+using namespace std;
+
+void SWSSSonicDBConfig_initialize(const char *path) {
+    SWSSTry(SonicDBConfig::initialize(path));
+}
+
+void SWSSSonicDBConfig_initializeGlobalConfig(const char *path) {
+    SWSSTry(SonicDBConfig::initializeGlobalConfig(path));
+}
+
+SWSSDBConnector SWSSDBConnector_new_tcp(int32_t dbId, const char *hostname, uint16_t port,
+                                        uint32_t timeout) {
+    SWSSTry(return (SWSSDBConnector) new DBConnector(dbId, string(hostname), port, timeout));
+}
+
+SWSSDBConnector SWSSDBConnector_new_unix(int32_t dbId, const char *sock_path, uint32_t timeout) {
+    SWSSTry(return (SWSSDBConnector) new DBConnector(dbId, string(sock_path), timeout));
+}
+
+SWSSDBConnector SWSSDBConnector_new_named(const char *dbName, uint32_t timeout_ms, uint8_t isTcpConn) {
+    SWSSTry(return (SWSSDBConnector) new DBConnector(string(dbName), timeout_ms, isTcpConn));
+}
+
+void SWSSDBConnector_free(SWSSDBConnector db) {
+    delete (DBConnector *)db;
+}
+
+int8_t SWSSDBConnector_del(SWSSDBConnector db, const char *key) {
+    SWSSTry(return ((DBConnector *)db)->del(string(key)) ? 1 : 0);
+}
+
+void SWSSDBConnector_set(SWSSDBConnector db, const char *key, const char *value) {
+    SWSSTry(((DBConnector *)db)->set(string(key), string(value)));
+}
+
+char *SWSSDBConnector_get(SWSSDBConnector db, const char *key) {
+    SWSSTry({
+        shared_ptr<string> s = ((DBConnector *)db)->get(string(key));
+        return s ? strdup(s->c_str()) : nullptr;
+    });
+}
+
+int8_t SWSSDBConnector_exists(SWSSDBConnector db, const char *key) {
+    SWSSTry(return ((DBConnector *)db)->exists(string(key)) ? 1 : 0);
+}
+
+int8_t SWSSDBConnector_hdel(SWSSDBConnector db, const char *key, const char *field) {
+    SWSSTry(return ((DBConnector *)db)->hdel(string(key), string(field)) ? 1 : 0);
+}
+
+void SWSSDBConnector_hset(SWSSDBConnector db, const char *key, const char *field,
+                          const char *value) {
+    SWSSTry(((DBConnector *)db)->hset(string(key), string(field), string(value)));
+}
+
+char *SWSSDBConnector_hget(SWSSDBConnector db, const char *key, const char *field) {
+    SWSSTry({
+        shared_ptr<string> s = ((DBConnector *)db)->hget(string(key), string(field));
+        return s ? strdup(s->c_str()) : nullptr;
+    });
+}
+
+SWSSFieldValueArray SWSSDBConnector_hgetall(SWSSDBConnector db, const char *key) {
+    SWSSTry({
+        auto map = ((DBConnector *)db)->hgetall(key);
+        return makeFieldValueArray(map);
+    });
+}
+
+int8_t SWSSDBConnector_hexists(SWSSDBConnector db, const char *key, const char *field) {
+    SWSSTry(return ((DBConnector *)db)->hexists(string(key), string(field)) ? 1 : 0);
+}
+
+int8_t SWSSDBConnector_flushdb(SWSSDBConnector db) {
+    SWSSTry(return ((DBConnector *)db)->flushdb() ? 1 : 0);
+}

common/c-api/dbconnector.h

@@ -0,0 +1,101 @@
+#ifndef SWSS_COMMON_C_API_DBCONNECTOR_H
+#define SWSS_COMMON_C_API_DBCONNECTOR_H
+
+#include "util.h"
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include <stdint.h>
+
+void SWSSSonicDBConfig_initialize(const char *path);
+
+void SWSSSonicDBConfig_initializeGlobalConfig(const char *path);
+
+typedef struct SWSSDBConnectorOpaque *SWSSDBConnector;
+
+// Pass 0 to timeout for infinity
+SWSSDBConnector SWSSDBConnector_new_tcp(int32_t dbId, const char *hostname, uint16_t port,
+                                        uint32_t timeout_ms);
+
+// Pass 0 to timeout for infinity
+SWSSDBConnector SWSSDBConnector_new_unix(int32_t dbId, const char *sock_path, uint32_t timeout_ms);
+
+// Pass 0 to timeout for infinity
+SWSSDBConnector SWSSDBConnector_new_named(const char *dbName, uint32_t timeout_ms, uint8_t isTcpConn);
+
+void SWSSDBConnector_free(SWSSDBConnector db);
+
+// Returns 0 when key doesn't exist, 1 when key was deleted
+int8_t SWSSDBConnector_del(SWSSDBConnector db, const char *key);
+
+void SWSSDBConnector_set(SWSSDBConnector db, const char *key, const char *value);
+
+// Returns NULL if key doesn't exist.
+// Result must be freed using free()
+char *SWSSDBConnector_get(SWSSDBConnector db, const char *key);
+
+// Returns 0 for false, 1 for true
+int8_t SWSSDBConnector_exists(SWSSDBConnector db, const char *key);
+
+// Returns 0 when key or field doesn't exist, 1 when field was deleted
+int8_t SWSSDBConnector_hdel(SWSSDBConnector db, const char *key, const char *field);
+
+void SWSSDBConnector_hset(SWSSDBConnector db, const char *key, const char *field,
+                          const char *value);
+
+// Returns NULL if key or field doesn't exist.
+// Result must be freed using free()
+char *SWSSDBConnector_hget(SWSSDBConnector db, const char *key, const char *field);
+
+// Returns an empty map when the key doesn't exist.
+// Result array and all of its elements must be freed using free()
+SWSSFieldValueArray SWSSDBConnector_hgetall(SWSSDBConnector db, const char *key);
+
+// Returns 0 when key or field doesn't exist, 1 when field exists
+int8_t SWSSDBConnector_hexists(SWSSDBConnector db, const char *key, const char *field);
+
+// std::vector<std::string> keys(const std::string &key);
+
+// std::pair<int, std::vector<std::string>> scan(int cursor = 0, const char
+// *match = "", uint32_t count = 10);
+
+// template<typename InputIterator>
+// void hmset(const std::string &key, InputIterator start, InputIterator stop);
+
+// void hmset(const std::unordered_map<std::string,
+// std::vector<std::pair<std::string, std::string>>>& multiHash);
+
+// std::shared_ptr<std::string> get(const std::string &key);
+
+// std::shared_ptr<std::string> hget(const std::string &key, const std::string
+// &field);
+
+// int64_t incr(const std::string &key);
+
+// int64_t decr(const std::string &key);
+
+// int64_t rpush(const std::string &list, const std::string &item);
+
+// std::shared_ptr<std::string> blpop(const std::string &list, int timeout);
+
+// void subscribe(const std::string &pattern);
+
+// void psubscribe(const std::string &pattern);
+
+// void punsubscribe(const std::string &pattern);
+
+// int64_t publish(const std::string &channel, const std::string &message);
+
+// void config_set(const std::string &key, const std::string &value);
+
+// Returns 1 on success, 0 on failure
+int8_t SWSSDBConnector_flushdb(SWSSDBConnector db);
+
+// std::map<std::string, std::map<std::string, std::map<std::string,
+// std::string>>> getall();
+#ifdef __cplusplus
+}
+#endif
+
+#endif

common/c-api/producerstatetable.cpp

@@ -0,0 +1,53 @@
+#include <cstring>
+#include <string>
+
+#include "../dbconnector.h"
+#include "../producerstatetable.h"
+#include "dbconnector.h"
+#include "producerstatetable.h"
+#include "util.h"
+
+using namespace swss;
+using namespace std;
+
+SWSSProducerStateTable SWSSProducerStateTable_new(SWSSDBConnector db, const char *tableName) {
+    SWSSTry(return (SWSSProducerStateTable) new ProducerStateTable((DBConnector *)db,
+                                                                   string(tableName)));
+}
+
+void SWSSProducerStateTable_free(SWSSProducerStateTable tbl) {
+    SWSSTry(delete ((ProducerStateTable *)tbl));
+}
+
+void SWSSProducerStateTable_setBuffered(SWSSProducerStateTable tbl, uint8_t buffered) {
+    SWSSTry(((ProducerStateTable *)tbl)->setBuffered((bool)buffered))
+}
+
+void SWSSProducerStateTable_set(SWSSProducerStateTable tbl, const char *key,
+                                SWSSFieldValueArray values) {
+    SWSSTry(((ProducerStateTable *)tbl)->set(string(key), takeFieldValueArray(values)));
+}
+
+void SWSSProducerStateTable_del(SWSSProducerStateTable tbl, const char *key) {
+    SWSSTry(((ProducerStateTable *)tbl)->del(string(key)));
+}
+
+void SWSSProducerStateTable_flush(SWSSProducerStateTable tbl) {
+    SWSSTry(((ProducerStateTable *)tbl)->flush());
+}
+
+int64_t SWSSProducerStateTable_count(SWSSProducerStateTable tbl) {
+    SWSSTry(return ((ProducerStateTable *)tbl)->count());
+}
+
+void SWSSProducerStateTable_clear(SWSSProducerStateTable tbl) {
+    SWSSTry(((ProducerStateTable *)tbl)->clear());
+}
+
+void SWSSProducerStateTable_create_temp_view(SWSSProducerStateTable tbl) {
+    SWSSTry(((ProducerStateTable *)tbl)->create_temp_view());
+}
+
+void SWSSProducerStateTable_apply_temp_view(SWSSProducerStateTable tbl) {
+    SWSSTry(((ProducerStateTable *)tbl)->apply_temp_view());
+}