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// Copyright 2015 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 <stdio.h>
#include <string.h>
#include <assert.h>
#include <emscripten.h>
extern "C" {
void EMSCRIPTEN_KEEPALIVE finish() {
// load some file data, SYNCHRONOUSLY :)
char buffer[100];
int num;
printf("load first file\n");
FILE *f1 = fopen("files/file1.txt", "r");
assert(f1);
num = fread(buffer, 1, 5, f1);
assert(num == 5);
fclose(f1);
buffer[5] = 0;
assert(strcmp(buffer, "first") == 0);
printf("load second file\n");
FILE *f2 = fopen("files/sub/file2.txt", "r");
assert(f2);
num = fread(buffer, 1, 6, f2);
assert(num == 6);
fclose(f2);
buffer[6] = 0;
assert(strcmp(buffer, "second") == 0);
// all done
printf("success\n");
REPORT_RESULT(1);
}
}
int main() {
// Load the metadata and data of our file package. When they arrive, load the contents of the package into our filesystem.
// The data arrives as a Blob, which could in other cases arrive from any other way a Blob can arrive:
// * Local file the user selected
// * Data loaded from IndexedDB
// In all cases, including the one here of a network request, Blobs allow the browser to optimize them so that
// a large file is not necessarily all in memory at once.
EM_ASM((
var meta, blob;
function maybeReady() {
if (!(meta && blob)) return;
meta = JSON.parse(meta);
out('loading into filesystem');
FS.mkdir('/files');
FS.mount(WORKERFS, {
packages: [{ metadata: meta, blob: blob }]
}, '/files');
ccall('finish');
}
fetch("files.js.metadata")
.then((rsp) => rsp.text())
.then((text) => {
out('got metadata');
meta = text;
maybeReady();
});
fetch("files.data")
.then((rsp) => rsp.blob())
.then((data) => {
blob = data;
maybeReady();
});
));
emscripten_exit_with_live_runtime();
return 1;
}
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