Re: [PATCH v5 11/40] odb-helper: add odb_helper_init() to send 'init' instruction

On Sun, Sep 10, 2017 at 2:12 PM, Lars Schneider
[off-list ref] wrote:

quoted

On 03 Aug 2017, at 10:18, Christian Couder [off-list ref] wrote:

+static void parse_capabilities(char *cap_buf,
+                            unsigned int *supported_capabilities,
+                            const char *process_name)
+{
+     struct string_list cap_list = STRING_LIST_INIT_NODUP;
+
+     string_list_split_in_place(&cap_list, cap_buf, '=', 1);
+
+     if (cap_list.nr == 2 && !strcmp(cap_list.items[0].string, "capability")) {
+             const char *cap_name = cap_list.items[1].string;
+
+             if (!strcmp(cap_name, "get_git_obj")) {
+                     *supported_capabilities |= ODB_HELPER_CAP_GET_GIT_OBJ;
+             } else if (!strcmp(cap_name, "get_raw_obj")) {
+                     *supported_capabilities |= ODB_HELPER_CAP_GET_RAW_OBJ;
+             } else if (!strcmp(cap_name, "get_direct")) {
+                     *supported_capabilities |= ODB_HELPER_CAP_GET_DIRECT;
+             } else if (!strcmp(cap_name, "put_git_obj")) {
+                     *supported_capabilities |= ODB_HELPER_CAP_PUT_GIT_OBJ;
+             } else if (!strcmp(cap_name, "put_raw_obj")) {
+                     *supported_capabilities |= ODB_HELPER_CAP_PUT_RAW_OBJ;
+             } else if (!strcmp(cap_name, "put_direct")) {
+                     *supported_capabilities |= ODB_HELPER_CAP_PUT_DIRECT;
+             } else if (!strcmp(cap_name, "have")) {
+                     *supported_capabilities |= ODB_HELPER_CAP_HAVE;
+             } else {
+                     warning("external process '%s' requested unsupported read-object capability '%s'",
+                             process_name, cap_name);
+             }

In 1514c8ed ("convert: refactor capabilities negotiation", 2017-06-30) I introduced
a simpler version of the capabilities negotiation. Maybe useful for you here, too?

Yeah, actually there is also fa64a2fdbe (sub-process: refactor
handshake to common function, 2017-07-26) that Jonathan Tan wrote on
top of your changes and that adds subprocess_handshake(). So the
current code is using it like that:

static int start_object_process_fn(struct subprocess_entry *subprocess)
{
    static int versions[] = {1, 0};
    static struct subprocess_capability capabilities[] = {
        { "get_git_obj", ODB_HELPER_CAP_GET_GIT_OBJ },
        { "get_raw_obj", ODB_HELPER_CAP_GET_RAW_OBJ },
        { "get_direct",  ODB_HELPER_CAP_GET_DIRECT  },
        { "put_git_obj", ODB_HELPER_CAP_PUT_GIT_OBJ },
        { "put_raw_obj", ODB_HELPER_CAP_PUT_RAW_OBJ },
        { "put_direct",  ODB_HELPER_CAP_PUT_DIRECT  },
        { "have",        ODB_HELPER_CAP_HAVE },
        { NULL, 0 }
    };
    struct object_process *entry = (struct object_process *)subprocess;
    return subprocess_handshake(subprocess, "git-read-object", versions, NULL,
                    capabilities,
                    &entry->supported_capabilities);
}