Allow to find any partition type (app and data) with iterator (IDFGH-4783)

[0xFEEDC0DE64]

I tried to build an remove partition browser tool which lists all types and subtypes of partitions and I was missing the partition type "ANY".

Example usage:

    JsonDocument doc;
    auto iter = esp_partition_find(ESP_PARTITION_TYPE_ANY, ESP_PARTITION_SUBTYPE_ANY, nullptr);

    while (iter)
    {
        auto part = esp_partition_get(iter);
        if (!part)
            break;

        auto obj = doc.createNestedObject();
        obj["type"] = part->type;
        obj["subtype"] = part->subtype;
        obj["address"] = part->address;
        obj["size"] = part->size;
        obj["label"] = std::string{part->label};
        obj["encrypted"] = part->encrypted;

        iter = esp_partition_next(iter);
    }

    if (iter)
        esp_partition_iterator_release(iter);

[Alvin1Zhang]

Thanks for your contribution.

[0xFEEDC0DE64]

Ok is this PR already in consideration? Are any questions open? Can I help somehow to get this merged?

[igrr]

Hi @0xFEEDC0DE64, thank you for the PR, and sorry that it took a long time for us to take a look.

Would you be okay with 2 changes being added to your commit?

1. Return NULL from esp_partition_find if type == ESP_PARTITION_TYPE_ANY and subtype != ESP_PARTITION_SUBTYPE_ANY, as such combination of arguments doesn't make sense:

    if (type == ESP_PARTITION_TYPE_ANY && subtype != ESP_PARTITION_SUBTYPE_ANY) {
        return NULL;
    }

2. In test_partition.c, extend the existing test case to exercise the newly added logic:

    it = esp_partition_find(ESP_PARTITION_TYPE_ANY, ESP_PARTITION_SUBTYPE_ANY, NULL);
    TEST_ASSERT_NOT_NULL(it);
    count = 0;
    for (; it != NULL; it = esp_partition_next(it)) {
        ++count;
    }
    esp_partition_iterator_release(it);
    TEST_ASSERT_EQUAL(8, count);

If this looks okay to you, I'll submit this internally.

(Edit: fixed a mistake in the first part, returning NULL instead of ESP_ERR_INVALID_ARG).

[igrr]

@0xFEEDC0DE64 the PR has been cherry-picked as 1f419bd, thanks again!