Increase JSON buffer size on overflow (#3475)

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[pʲɵs] 2022-05-15 09:53:43 +02:00 committed by Jesse Hills
parent ff72d6a146
commit 01222dbab7
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@ -26,21 +26,33 @@ std::string build_json(const json_build_t &f) {
const size_t free_heap = heap_caps_get_largest_free_block(MALLOC_CAP_8BIT);
#endif
const size_t request_size = std::min(free_heap, (size_t) 512);
DynamicJsonDocument json_document(request_size);
if (json_document.capacity() == 0) {
ESP_LOGE(TAG, "Could not allocate memory for JSON document! Requested %u bytes, largest free heap block: %u bytes",
request_size, free_heap);
return "{}";
size_t request_size = std::min(free_heap, (size_t) 512);
while (true) {
ESP_LOGV(TAG, "Attempting to allocate %u bytes for JSON serialization", request_size);
DynamicJsonDocument json_document(request_size);
if (json_document.capacity() == 0) {
ESP_LOGE(TAG,
"Could not allocate memory for JSON document! Requested %u bytes, largest free heap block: %u bytes",
request_size, free_heap);
return "{}";
}
JsonObject root = json_document.to<JsonObject>();
f(root);
if (json_document.overflowed()) {
if (request_size == free_heap) {
ESP_LOGE(TAG, "Could not allocate memory for JSON document! Overflowed largest free heap block: %u bytes",
free_heap);
return "{}";
}
request_size = std::min(request_size * 2, free_heap);
continue;
}
json_document.shrinkToFit();
ESP_LOGV(TAG, "Size after shrink %u bytes", json_document.capacity());
std::string output;
serializeJson(json_document, output);
return output;
}
JsonObject root = json_document.to<JsonObject>();
f(root);
json_document.shrinkToFit();
ESP_LOGV(TAG, "Size after shrink %u bytes", json_document.capacity());
std::string output;
serializeJson(json_document, output);
return output;
}
void parse_json(const std::string &data, const json_parse_t &f) {