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// Copyright 2016 The Emscripten Authors. All rights reserved.
// Emscripten is available under two separate licenses, the MIT license and the
// University of Illinois/NCSA Open Source License. Both these licenses can be
// found in the LICENSE file.
#include <string.h>
#include <stdio.h>
#include <math.h>
#include <assert.h>
#include <emscripten/fetch.h>
// Compute rudimentary checksum of data
uint32_t checksum = 0;
int result = 0;
int main()
{
emscripten_fetch_attr_t attr;
emscripten_fetch_attr_init(&attr);
strcpy(attr.requestMethod, "GET");
attr.onsuccess = [](emscripten_fetch_t *fetch) {
printf("Finished downloading %llu bytes\n", fetch->totalBytes);
printf("Data checksum: %08X\n", checksum);
assert(fetch->data == 0); // The data was streamed via onprogress, no bytes available here.
assert(fetch->numBytes == 0);
assert(fetch->totalBytes == 134217728);
assert(checksum == 0xA7F8E858U);
emscripten_fetch_close(fetch);
#ifdef REPORT_RESULT
// Fetch API appears to sometimes call the handlers more than once, see https://github.com/emscripten-core/emscripten/pull/8191
MAYBE_REPORT_RESULT(1);
#endif
};
attr.onprogress = [](emscripten_fetch_t *fetch) {
printf("Downloading.. %.2f%s complete. Received chunk [%llu, %llu[\n",
(fetch->totalBytes > 0) ? ((fetch->dataOffset + fetch->numBytes) * 100.0 / fetch->totalBytes) : (double)(fetch->dataOffset + fetch->numBytes),
(fetch->totalBytes > 0) ? "%" : " bytes",
fetch->dataOffset,
fetch->dataOffset + fetch->numBytes);
assert(fetch->data != 0);
assert(fetch->numBytes > 0);
assert(fetch->dataOffset + fetch->numBytes <= fetch->totalBytes);
assert(fetch->totalBytes <= 134217728);
for(int i = 0; i < fetch->numBytes; ++i)
checksum = ((checksum << 8) | (checksum >> 24)) * fetch->data[i] + fetch->data[i];
};
attr.attributes = EMSCRIPTEN_FETCH_LOAD_TO_MEMORY | EMSCRIPTEN_FETCH_APPEND | EMSCRIPTEN_FETCH_STREAM_DATA;
emscripten_fetch_t *fetch = emscripten_fetch(&attr, "largefile.txt");
}
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