Make some use of anonymous unions [libpq-oauth]

Make some use of anonymous unions, which are allowed as of C11, as
examples and encouragement for future code, and to test compilers.

This commit changes the json_field struct.

Reviewed-by: Nathan Bossart <nathandbossart@gmail.com>
Discussion: https://postgr.es/m/CAOYmi%2BnV25oC5uXFgWodydGrHkfWMDCLUcjbAreM3mNX%3DF2JWw%40mail.gmail.com

diff --git a/src/interfaces/libpq-oauth/oauth-curl.c b/src/interfaces/libpq-oauth/oauth-curl.c
index 08e300715da14935e7dc07c69c56ed9e1b225f7b..bd0a656a166dfa318727b57925f4558ef981d23a 100644 (file)
--- a/src/interfaces/libpq-oauth/oauth-curl.c
+++ b/src/interfaces/libpq-oauth/oauth-curl.c
@@ -439,7 +439,7 @@ struct json_field
    {
        char      **scalar;     /* for all scalar types */
        struct curl_slist **array;  /* for type == JSON_TOKEN_ARRAY_START */
-   }           target;
+   };
 
    bool        required;       /* REQUIRED field, or just OPTIONAL? */
 };
@@ -561,8 +561,8 @@ oauth_json_object_field_start(void *state, char *name, bool isnull)
        {
            field = ctx->active;
 
-           if ((field->type == JSON_TOKEN_ARRAY_START && *field->target.array)
-               || (field->type != JSON_TOKEN_ARRAY_START && *field->target.scalar))
+           if ((field->type == JSON_TOKEN_ARRAY_START && *field->array)
+               || (field->type != JSON_TOKEN_ARRAY_START && *field->scalar))
            {
                oauth_parse_set_error(ctx, "field \"%s\" is duplicated",
                                      field->name);
@@ -706,7 +706,7 @@ oauth_json_scalar(void *state, char *token, JsonTokenType type)
            }
 
            /* ...and that a result has not already been set. */
-           if (*field->target.scalar)
+           if (*field->scalar)
            {
                Assert(false);
                oauth_parse_set_error(ctx,
@@ -715,8 +715,8 @@ oauth_json_scalar(void *state, char *token, JsonTokenType type)
                return JSON_SEM_ACTION_FAILED;
            }
 
-           *field->target.scalar = strdup(token);
-           if (!*field->target.scalar)
+           *field->scalar = strdup(token);
+           if (!*field->scalar)
                return JSON_OUT_OF_MEMORY;
 
            ctx->active = NULL;
@@ -738,11 +738,11 @@ oauth_json_scalar(void *state, char *token, JsonTokenType type)
            }
 
            /* Note that curl_slist_append() makes a copy of the token. */
-           temp = curl_slist_append(*field->target.array, token);
+           temp = curl_slist_append(*field->array, token);
            if (!temp)
                return JSON_OUT_OF_MEMORY;
 
-           *field->target.array = temp;
+           *field->array = temp;
        }
    }
    else
@@ -878,8 +878,8 @@ parse_oauth_json(struct async_ctx *actx, const struct json_field *fields)
    while (fields->name)
    {
        if (fields->required
-           && !*fields->target.scalar
-           && !*fields->target.array)
+           && !*fields->scalar
+           && !*fields->array)
        {
            actx_error(actx, "field \"%s\" is missing", fields->name);
            goto cleanup;