7
我跟着Webassembly入門教程http://webassembly.org/getting-started/developers-guide/我可以使用Webassembly從磁盤讀取文件嗎？
它工作正常，並顯示「你好，世界！」消息在瀏覽器中。
然後我嘗試了一個小的C++代碼，打開一個文本文件並在讀取文件後進行計算（10 * 20）。
emcc編譯的文件就好了，沒有錯誤。
但是，當我通過運行emrun通過HTTP提供文件時，它無法打開文件。
這是我在emrun Web控制檯看到：
Unable to open file
200
是否有任何限制從本地磁盤打開的文件？
[[email protected] hello]$ cat pfile.cpp
#include <iostream>
#include <fstream>
#include <string>
using namespace std;
int main() {
string line;
int a, b, c;
ifstream myfile("test.txt");
if (myfile.is_open()) {
while (getline (myfile, line)) {
cout << line << endl;
}
myfile.close();
}
else cout << "Unable to open file" << endl;
a = 10;
b = 20;
c = a * b;
cout << c << endl;
return 0;
}
[[email protected] hello]$ emcc pfile.cpp -s WASM=1 -o pfile.html -v
INFO:root:(Emscripten: Running sanity checks)
clang version 4.0.0 (https://github.com/kripken/emscripten-fastcomp-clang.git c7c210fee24e0227f882337521b25b1ed9c36d5b) (https://github.com/kripken/emscripten-fastcomp.git 90b726ede4acf47c1bca089de6c79a0b8f2c5d9a) (emscripten 1.37.18 : 1.37.18)
Target: asmjs-unknown-emscripten
Thread model: posix
InstalledDir: /home/thiago/Downloads/emsdk/clang/fastcomp/build_incoming_64/bin
"/home/thiago/Downloads/emsdk/clang/fastcomp/build_incoming_64/bin/clang-4.0" -cc1 -triple asmjs-unknown-emscripten -emit-llvm-bc -emit-llvm-uselists -disable-free -main-file-name pfile.cpp -mrelocation-model static -mthread-model posix -mdisable-fp-elim -no-integrated-as -mconstructor-aliases -v -dwarf-column-info -debugger-tuning=gdb -coverage-notes-file /tmp/tmpV3VHOz/pfile_0.gcno -nostdsysteminc -nobuiltininc -resource-dir /home/thiago/Downloads/emsdk/clang/fastcomp/build_incoming_64/bin/../lib/clang/4.0.0 -D __EMSCRIPTEN_major__=1 -D __EMSCRIPTEN_minor__=37 -D __EMSCRIPTEN_tiny__=18 -D _LIBCPP_ABI_VERSION=2 -Werror=implicit-function-declaration -std=c++03 -fdeprecated-macro -fno-dwarf-directory-asm -fdebug-compilation-dir /home/thiago/hello -ferror-limit 19 -fmessage-length 164 -fobjc-runtime=gnustep -fcxx-exceptions -fexceptions -fdiagnostics-show-option -nobuiltininc -nostdsysteminc -isystem/home/thiago/Downloads/emsdk/emscripten/incoming/system/include/libcxx -isystem/home/thiago/Downloads/emsdk/emscripten/incoming/system/lib/libcxxabi/include -isystem/home/thiago/Downloads/emsdk/emscripten/incoming/system/include/compat -isystem/home/thiago/Downloads/emsdk/emscripten/incoming/system/include -isystem/home/thiago/Downloads/emsdk/emscripten/incoming/system/include/SSE -isystem/home/thiago/Downloads/emsdk/emscripten/incoming/system/include/libc -isystem/home/thiago/Downloads/emsdk/emscripten/incoming/system/lib/libc/musl/arch/emscripten -isystem/home/thiago/Downloads/emsdk/emscripten/incoming/system/local/include -isystem/home/thiago/Downloads/emsdk/emscripten/incoming/system/include/SDL -o /tmp/tmpV3VHOz/pfile_0.o -x c++ pfile.cpp
clang -cc1 version 4.0.0 based upon LLVM 4.0.0 default target x86_64-unknown-linux-gnu
#include "..." search starts here:
#include <...> search starts here:
/home/thiago/Downloads/emsdk/emscripten/incoming/system/include/libcxx
/home/thiago/Downloads/emsdk/emscripten/incoming/system/lib/libcxxabi/include
/home/thiago/Downloads/emsdk/emscripten/incoming/system/include/compat
/home/thiago/Downloads/emsdk/emscripten/incoming/system/include
/home/thiago/Downloads/emsdk/emscripten/incoming/system/include/SSE
/home/thiago/Downloads/emsdk/emscripten/incoming/system/include/libc
/home/thiago/Downloads/emsdk/emscripten/incoming/system/lib/libc/musl/arch/emscripten
/home/thiago/Downloads/emsdk/emscripten/incoming/system/local/include
/home/thiago/Downloads/emsdk/emscripten/incoming/system/include/SDL
End of search list.
[[email protected] hello]$ emrun --no_browser --port 8080 .
當然有限制。如果沒有限制，那麼webassembly將是一個巨大的巨大安全漏洞。 –
你有沒有得到任何解決方案？ –