Add swss::Table to c api

common/Makefile.am

@@ -79,6 +79,7 @@ common_libswsscommon_la_SOURCES = \
     common/c-api/zmqserver.cpp             \
     common/c-api/zmqconsumerstatetable.cpp \
     common/c-api/zmqproducerstatetable.cpp \
+    common/c-api/table.cpp                 \
     common/performancetimer.cpp
 
 common_libswsscommon_la_CXXFLAGS = $(DBGFLAGS) $(AM_CFLAGS) $(CFLAGS_COMMON) $(LIBNL_CFLAGS) $(CODE_COVERAGE_CXXFLAGS)

common/c-api/table.cpp

@@ -0,0 +1,71 @@
+#include <string>
+#include <vector>
+
+#include "../dbconnector.h"
+#include "../table.h"
+#include "table.h"
+#include "util.h"
+
+using namespace swss;
+using namespace std;
+
+SWSSTable SWSSTable_new(SWSSDBConnector db, const char *tableName) {
+    SWSSTry(return (SWSSTable) new Table((DBConnector *)db, string(tableName)));
+}
+
+void SWSSTable_free(SWSSTable tbl) {
+    SWSSTry(delete (Table *)tbl);
+}
+
+int8_t SWSSTable_get(SWSSTable tbl, const char *key, SWSSFieldValueArray *outValues) {
+    SWSSTry({
+        vector<FieldValueTuple> fvs;
+        bool exists = ((Table *)tbl)->get(string(key), fvs);
+        if (exists) {
+            *outValues = makeFieldValueArray(fvs);
+            return 1;
+        } else {
+            return 0;
+        }
+    });
+}
+
+int8_t SWSSTable_hget(SWSSTable tbl, const char *key, const char *field, SWSSString *outValue) {
+    SWSSTry({
+        string s;
+        bool exists = ((Table *)tbl)->hget(string(key), string(field), s);
+        if (exists) {
+            *outValue = makeString(move(s));
+            return 1;
+        } else {
+            return 0;
+        }
+    });
+}
+
+void SWSSTable_set(SWSSTable tbl, const char *key, SWSSFieldValueArray values) {
+    SWSSTry({
+        vector<FieldValueTuple> fvs = takeFieldValueArray(values);
+        ((Table *)tbl)->set(string(key), fvs);
+    });
+}
+
+void SWSSTable_hset(SWSSTable tbl, const char *key, const char *field, SWSSStrRef value) {
+    SWSSTry({ ((Table *)tbl)->hset(string(key), string(field), takeStrRef(value)); });
+}
+
+void SWSSTable_del(SWSSTable tbl, const char *key) {
+    SWSSTry({ ((Table *)tbl)->del(string(key)); });
+}
+
+void SWSSTable_hdel(SWSSTable tbl, const char *key, const char *field) {
+    SWSSTry({ ((Table *)tbl)->hdel(string(key), string(field)); });
+}
+
+SWSSStringArray SWSSTable_getKeys(SWSSTable tbl) {
+    SWSSTry({
+        vector<string> keys;
+        ((Table *)tbl)->getKeys(keys);
+        return makeStringArray(move(keys));
+    })
+}

common/c-api/table.h

@@ -0,0 +1,41 @@
+#ifndef SWSS_COMMON_C_API_TABLE_H
+#define SWSS_COMMON_C_API_TABLE_H
+
+#include "dbconnector.h"
+#include "util.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include <stdint.h>
+
+typedef struct SWSSTableOpaque *SWSSTable;
+
+SWSSTable SWSSTable_new(SWSSDBConnector db, const char *tableName);
+
+void SWSSTable_free(SWSSTable tbl);
+
+// If the key exists, populates outValues with the table's values and returns 1. 
+// If the key doesn't exist, returns 0.
+int8_t SWSSTable_get(SWSSTable tbl, const char *key, SWSSFieldValueArray *outValues);
+
+// If the key and field exist, populates outValue with the field's value and returns 1. 
+// If the key doesn't exist, returns 0.
+int8_t SWSSTable_hget(SWSSTable tbl, const char *key, const char *field, SWSSString *outValue);
+
+void SWSSTable_set(SWSSTable tbl, const char *key, SWSSFieldValueArray values);
+
+void SWSSTable_hset(SWSSTable tbl, const char *key, const char *field, SWSSStrRef value);
+
+void SWSSTable_del(SWSSTable tbl, const char *key);
+
+void SWSSTable_hdel(SWSSTable tbl, const char *key, const char *field);
+
+SWSSStringArray SWSSTable_getKeys(SWSSTable tbl);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif

common/c-api/util.cpp

@@ -31,3 +31,7 @@ void SWSSFieldValueArray_free(SWSSFieldValueArray arr) {
 void SWSSKeyOpFieldValuesArray_free(SWSSKeyOpFieldValuesArray kfvs) {
     SWSSTry(delete[] kfvs.data);
 }
+
+void SWSSStringArray_free(SWSSStringArray arr) {
+    SWSSTry(delete[] arr.data);
+}

common/c-api/util.h

@@ -19,6 +19,7 @@ typedef struct SWSSStringOpaque *SWSSString;
 typedef struct SWSSStrRefOpaque *SWSSStrRef;
 
 // FFI version of swss::FieldValueTuple
+// field should be freed with libc's free()
 typedef struct {
     const char *field;
     SWSSString value;
@@ -59,6 +60,13 @@ typedef enum {
     SWSSSelectResult_SIGNAL = 2,
 } SWSSSelectResult;
 
+// FFI version of std::vector<std::string>
+// data strings should be freed with libc's free()
+typedef struct {
+    uint64_t len;
+    const char **data;
+} SWSSStringArray;
+
 // data should not include a null terminator
 SWSSString SWSSString_new(const char *data, uint64_t length);
 
@@ -85,6 +93,10 @@ void SWSSFieldValueArray_free(SWSSFieldValueArray arr);
 // grained control of ownership).
 void SWSSKeyOpFieldValuesArray_free(SWSSKeyOpFieldValuesArray kfvs);
 
+// arr.data may be null. This is not recursive - elements must be freed separately (for finer
+// grained control of ownership).
+void SWSSStringArray_free(SWSSStringArray arr);
+
 #ifdef __cplusplus
 }
 #endif
@@ -214,6 +226,19 @@ template <class T> static inline SWSSKeyOpFieldValuesArray makeKeyOpFieldValuesA
     return out;
 }
 
+static inline SWSSStringArray makeStringArray(std::vector<std::string> &&in) {
+    const char **data = new const char*[in.size()];
+
+    size_t i = 0;
+    for (std::string &s : in)
+        data[i++] = strdup(s.c_str());
+
+    SWSSStringArray out;
+    out.len = (uint64_t)in.size();
+    out.data = data;
+    return out;
+}
+
 static inline std::string takeString(SWSSString s) {
     return std::string(std::move(*((std::string *)s)));
 }

tests/c_api_ut.cpp

@@ -5,6 +5,7 @@
 #include "common/c-api/dbconnector.h"
 #include "common/c-api/producerstatetable.h"
 #include "common/c-api/subscriberstatetable.h"
+#include "common/c-api/table.h"
 #include "common/c-api/util.h"
 #include "common/c-api/zmqclient.h"
 #include "common/c-api/zmqconsumerstatetable.h"
@@ -40,14 +41,18 @@ static void sortKfvs(vector<KeyOpFieldsValuesTuple> &kfvs) {
 
 #define free(x) std::free(const_cast<void *>(reinterpret_cast<const void *>(x)));
 
+static void freeFieldValuesArray(SWSSFieldValueArray arr) {
+    for (uint64_t i = 0; i < arr.len; i++) {
+        free(arr.data[i].field);
+        SWSSString_free(arr.data[i].value);
+    }
+    SWSSFieldValueArray_free(arr);
+}
+
 static void freeKeyOpFieldValuesArray(SWSSKeyOpFieldValuesArray arr) {
     for (uint64_t i = 0; i < arr.len; i++) {
         free(arr.data[i].key);
-        for (uint64_t j = 0; j < arr.data[i].fieldValues.len; j++) {
-            free(arr.data[i].fieldValues.data[j].field);
-            SWSSString_free(arr.data[i].fieldValues.data[j].value);
-        }
-        SWSSFieldValueArray_free(arr.data[i].fieldValues);
+        freeFieldValuesArray(arr.data[i].fieldValues);
     }
     SWSSKeyOpFieldValuesArray_free(arr);
 }
@@ -105,6 +110,57 @@ TEST(c_api, DBConnector) {
     SWSSDBConnector_free(db);
 }
 
+TEST(c_api, Table) {
+    clearDB();
+    SWSSStringManager sm;
+
+    SWSSDBConnector db = SWSSDBConnector_new_named("TEST_DB", 1000, true);
+    SWSSTable tbl = SWSSTable_new(db, "mytable");
+
+    SWSSFieldValueArray fvs;
+    SWSSString ss;
+    EXPECT_FALSE(SWSSTable_get(tbl, "mykey", &fvs));
+    EXPECT_FALSE(SWSSTable_hget(tbl, "mykey", "myfield", &ss));
+
+    SWSSStringArray keys = SWSSTable_getKeys(tbl);
+    EXPECT_EQ(keys.len, 0);
+    SWSSStringArray_free(keys);
+
+    SWSSTable_hset(tbl, "mykey", "myfield", sm.makeStrRef("myvalue"));
+    keys = SWSSTable_getKeys(tbl);
+    ASSERT_EQ(keys.len, 1);
+    EXPECT_STREQ(keys.data[0], "mykey");
+    free(keys.data[0]);
+    SWSSStringArray_free(keys);
+
+    ASSERT_TRUE(SWSSTable_hget(tbl, "mykey", "myfield", &ss));
+    EXPECT_STREQ(SWSSStrRef_c_str((SWSSStrRef)ss), "myvalue");
+    SWSSString_free(ss);
+
+    SWSSTable_hdel(tbl, "mykey", "myfield");
+    EXPECT_FALSE(SWSSTable_hget(tbl, "mykey", "myfield", &ss));
+
+    SWSSFieldValueTuple data[2] = {{.field = "myfield1", .value = sm.makeString("myvalue1")},
+                                   {.field = "myfield2", .value = sm.makeString("myvalue2")}};
+    fvs.len = 2;
+    fvs.data = data;
+    SWSSTable_set(tbl, "mykey", fvs);
+
+    ASSERT_TRUE(SWSSTable_get(tbl, "mykey", &fvs));
+    EXPECT_EQ(fvs.len, 2);
+    EXPECT_STREQ(data[0].field, fvs.data[0].field);
+    EXPECT_STREQ(data[1].field, fvs.data[1].field);
+    freeFieldValuesArray(fvs);
+
+    SWSSTable_del(tbl, "mykey");
+    keys = SWSSTable_getKeys(tbl);
+    EXPECT_EQ(keys.len, 0);
+    SWSSStringArray_free(keys);
+
+    SWSSTable_free(tbl);
+    SWSSDBConnector_free(db);
+}
+
 TEST(c_api, ConsumerProducerStateTables) {
     clearDB();
     SWSSStringManager sm;
@@ -119,9 +175,8 @@ TEST(c_api, ConsumerProducerStateTables) {
     ASSERT_EQ(arr.len, 0);
     freeKeyOpFieldValuesArray(arr);
 
-    SWSSFieldValueTuple data[2] = {
-        {.field = "myfield1", .value = sm.makeString("myvalue1")},
-        {.field = "myfield2", .value = sm.makeString("myvalue2")}};
+    SWSSFieldValueTuple data[2] = {{.field = "myfield1", .value = sm.makeString("myvalue1")},
+                                   {.field = "myfield2", .value = sm.makeString("myvalue2")}};
     SWSSFieldValueArray values = {
         .len = 2,
         .data = data,
@@ -154,7 +209,7 @@ TEST(c_api, ConsumerProducerStateTables) {
     ASSERT_EQ(fieldValues1.size(), 1);
     EXPECT_EQ(fieldValues1[0].first, "myfield3");
     EXPECT_EQ(fieldValues1[0].second, "myvalue3");
-  
+
     arr = SWSSConsumerStateTable_pops(cst);
     EXPECT_EQ(arr.len, 0);
     freeKeyOpFieldValuesArray(arr);
@@ -244,14 +299,16 @@ TEST(c_api, ZmqConsumerProducerStateTable) {
     // On flag = 0, we use the ZmqProducerStateTable
     // On flag = 1, we use the ZmqClient directly
     for (int flag = 0; flag < 2; flag++) {
-        SWSSFieldValueTuple values_key1_data[2] = {{.field = "myfield1", .value = sm.makeString("myvalue1")},
-                                                  {.field = "myfield2", .value = sm.makeString("myvalue2")}};
+        SWSSFieldValueTuple values_key1_data[2] = {
+            {.field = "myfield1", .value = sm.makeString("myvalue1")},
+            {.field = "myfield2", .value = sm.makeString("myvalue2")}};
         SWSSFieldValueArray values_key1 = {
             .len = 2,
             .data = values_key1_data,
         };
 
-        SWSSFieldValueTuple values_key2_data[1] = {{.field = "myfield3", .value = sm.makeString("myvalue3")}};
+        SWSSFieldValueTuple values_key2_data[1] = {
+            {.field = "myfield3", .value = sm.makeString("myvalue3")}};
         SWSSFieldValueArray values_key2 = {
             .len = 1,
             .data = values_key2_data,