Implement support for oneofs (C unions).

Basic test included, should probably add an oneof to the AllTypes test also.

Update issue 131
Status: Started

4 files changed, 176 insertions, 0 deletions

diff --git a/tests/oneof/SConscript b/tests/oneof/SConscript
new file mode 100644
index 00000000..19845278
--- /dev/null
+++ b/tests/oneof/SConscript
@@ -0,0 +1,22 @@
+# Test the 'oneof' feature for generating C unions.
+
+Import('env')
+
+env.NanopbProto('oneof')
+
+enc = env.Program(['encode_oneof.c',
+                   'oneof.pb.c',
+                   '$COMMON/pb_encode.o',
+                   '$COMMON/pb_common.o'])
+
+dec = env.Program(['decode_oneof.c',
+                   'oneof.pb.c',
+                   '$COMMON/pb_decode.o',
+                   '$COMMON/pb_common.o'])
+
+env.RunTest("message1.pb", enc, ARGS = ['1'])
+env.RunTest("message1.txt", [dec, 'message1.pb'], ARGS = ['1'])
+env.RunTest("message2.pb", enc, ARGS = ['2'])
+env.RunTest("message2.txt", [dec, 'message2.pb'], ARGS = ['2'])
+env.RunTest("message3.pb", enc, ARGS = ['3'])
+env.RunTest("message3.txt", [dec, 'message3.pb'], ARGS = ['3'])
diff --git a/tests/oneof/decode_oneof.c b/tests/oneof/decode_oneof.c
new file mode 100644
index 00000000..e94becc7
--- /dev/null
+++ b/tests/oneof/decode_oneof.c
@@ -0,0 +1,72 @@
+/* Decode a message using oneof fields */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <pb_decode.h>
+#include "oneof.pb.h"
+#include "test_helpers.h"
+#include "unittests.h"
+
+int main(int argc, char **argv)
+{
+    uint8_t buffer[OneOfMessage_size];
+    OneOfMessage msg = OneOfMessage_init_zero;
+    pb_istream_t stream;
+    size_t count;
+    int option;
+
+    if (argc != 2)
+    {
+        fprintf(stderr, "Usage: encode_oneof [number]\n");
+        return 1;
+    }
+    option = atoi(argv[1]);
+
+    SET_BINARY_MODE(stdin);
+    count = fread(buffer, 1, sizeof(buffer), stdin);
+
+    if (!feof(stdin))
+    {
+        printf("Message does not fit in buffer\n");
+        return 1;
+    }
+
+    stream = pb_istream_from_buffer(buffer, count);
+
+    if (!pb_decode(&stream, OneOfMessage_fields, &msg))
+    {
+        printf("Decoding failed: %s\n", PB_GET_ERROR(&stream));
+        return 1;
+    }
+
+    {
+        int status = 0;
+
+        /* Check that the basic fields work normally */
+        TEST(msg.prefix == 123);
+        TEST(msg.suffix == 321);
+
+        /* Check that we got the right oneof according to command line */
+        if (option == 1)
+        {
+            TEST(msg.which_values == OneOfMessage_first_tag);
+            TEST(msg.values.first == 999);
+        }
+        else if (option == 2)
+        {
+            TEST(msg.which_values == OneOfMessage_second_tag);
+            TEST(strcmp(msg.values.second, "abcd") == 0);
+        }
+        else if (option == 3)
+        {
+            TEST(msg.which_values == OneOfMessage_third_tag);
+            TEST(msg.values.third.array[0] == 1);
+            TEST(msg.values.third.array[1] == 2);
+            TEST(msg.values.third.array[2] == 3);
+            TEST(msg.values.third.array[3] == 4);
+            TEST(msg.values.third.array[4] == 5);
+        }
+
+        return status;
+    }
+}
\ No newline at end of file
diff --git a/tests/oneof/encode_oneof.c b/tests/oneof/encode_oneof.c
new file mode 100644
index 00000000..913d2d43
--- /dev/null
+++ b/tests/oneof/encode_oneof.c
@@ -0,0 +1,64 @@
+/* Encode a message using oneof fields */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <pb_encode.h>
+#include "oneof.pb.h"
+#include "test_helpers.h"
+
+int main(int argc, char **argv)
+{
+    uint8_t buffer[OneOfMessage_size];
+    OneOfMessage msg = OneOfMessage_init_zero;
+    pb_ostream_t stream;
+    int option;
+
+    if (argc != 2)
+    {
+        fprintf(stderr, "Usage: encode_oneof [number]\n");
+        return 1;
+    }
+    option = atoi(argv[1]);
+
+    /* Prefix and suffix are used to test that the union does not disturb
+     * other fields in the same message. */
+    msg.prefix = 123;
+
+    /* We encode one of the 'values' fields based on command line argument */
+    if (option == 1)
+    {
+        msg.which_values = OneOfMessage_first_tag;
+        msg.values.first = 999;
+    }
+    else if (option == 2)
+    {
+        msg.which_values = OneOfMessage_second_tag;
+        strcpy(msg.values.second, "abcd");
+    }
+    else if (option == 3)
+    {
+        msg.which_values = OneOfMessage_third_tag;
+        msg.values.third.array_count = 5;
+        msg.values.third.array[0] = 1;
+        msg.values.third.array[1] = 2;
+        msg.values.third.array[2] = 3;
+        msg.values.third.array[3] = 4;
+        msg.values.third.array[4] = 5;
+    }
+
+    msg.suffix = 321;
+
+    stream = pb_ostream_from_buffer(buffer, sizeof(buffer));
+
+    if (pb_encode(&stream, OneOfMessage_fields, &msg))
+    {
+        SET_BINARY_MODE(stdout);
+        fwrite(buffer, 1, stream.bytes_written, stdout);
+        return 0;
+    }
+    else
+    {
+        fprintf(stderr, "Encoding failed: %s\n", PB_GET_ERROR(&stream));
+        return 1;
+    }
+}
diff --git a/tests/oneof/oneof.proto b/tests/oneof/oneof.proto
new file mode 100644
index 00000000..a89ef131
--- /dev/null
+++ b/tests/oneof/oneof.proto
@@ -0,0 +1,18 @@
+import 'nanopb.proto';
+
+message SubMessage
+{
+    repeated int32 array = 1 [(nanopb).max_count = 8];
+}
+
+message OneOfMessage
+{
+    required int32 prefix = 1;
+    oneof values
+    {
+        int32 first = 5;
+        string second = 6 [(nanopb).max_size = 8];
+        SubMessage third = 7;
+    }
+    required int32 suffix = 99;
+}