docker-compile-and-run en C++ fonctionnel, mais a coup de system

test~coding~readingCppPrograms.fr/compile-and-run.sh

+#!/bin/sh
+
+usage () {
+    echo compile-and-run [program.cpp]
+    echo
+    echo Compiles and executes a c++ program.
+    echo The standard input and output is passed down to the program.
+    echo The exit status is that of the compiler.
+}
+
+if [ x"$1" = "x" ]; then
+    usage
+    exit 0
+fi
+
+if g++ prog.cpp; then
+   ./a.out
+else
+    echo "Compilation failed 1>&2" 1>&2
+   exit $?
+fi
+

test~coding~readingCppPrograms.fr/docker-compile-and-run.cpp

+#include <vector>
+#include <iostream>
+#include <cstdlib>
+#include <sstream>
+using namespace std;
+
+#include <unistd.h>
+#include <sys/types.h>
+
+
+/**
+ * TODO:
+ * - [ ] set tight resources limits
+ * - [ ] make this into a program rather than a shell script for a minimum of safety
+ **/
+
+string compile_and_run = "compile-and-run.sh";
+//string bin_dir = "/home/wims/public_html/bin/";
+string bin_dir = "";
+string docker = "/usr/bin/docker";
+
+void usage () {
+    cerr << "docker-compile-and-run [program.cpp]" << endl;
+    cerr << endl;
+    cerr << "Compiles and executes a c++ program within a sandbox." << endl;
+    cerr << "The standard input and output is passed down to the program." << endl;
+    cerr << "The exit status is that of the compiler." << endl;
+}
+
+int system(string command) {
+    // cerr << "Running " << command << endl;
+    std::system(command.c_str());
+}
+
+#include <stdio.h>
+
+void exec(string cmd, const vector<string> args) {
+    cerr << "Running (exec): "+cmd;
+    for (auto arg: args)
+        cerr << " " << arg;
+    cerr << endl;
+    vector<const char*> argv;
+    argv.push_back(cmd.c_str());
+    for ( auto &s: args )
+        argv.push_back(s.c_str());
+    argv.push_back((char *) 0);
+
+    const vector<const char *> argv2(argv.begin(), argv.end());
+
+    int pid = fork();
+    if (pid==0) {
+        execv(cmd.c_str(), (char * const*)argv.data());
+    }
+}
+
+std::string pexec(const string cmd) {
+    cerr << "Running (pexec): "+cmd << endl;
+    FILE* pipe = popen(cmd.c_str(), "r");
+    if (!pipe) return "ERROR";
+    char buffer[128];
+    std::string result = "";
+    while (!feof(pipe)) {
+        if (fgets(buffer, 128, pipe) != NULL)
+            result += buffer;
+    }
+    pclose(pipe);
+    return result;
+}
+
+string docker_run(string container, string command) {
+    string ID = pexec(docker + " run -d "+container+" "+command);
+    // see http://stackoverflow.com/questions/216823/whats-the-best-way-to-trim-stdstring
+    ID.erase(ID.find_last_not_of(" \n\r\t")+1);
+    return ID;
+}
+
+void docker_oldexec(string docker_id, string command) {
+    string cmd = docker+" exec -i "+ docker_id+ " "+ command;
+    cerr << "Running (docker_oldexec): "+cmd << endl;
+    system(cmd);
+}
+
+void docker_exec(string docker_id, vector<string> args) {
+    vector<string> docker_args = {"exec", "-i", docker_id};
+    for (auto arg: args)
+        docker_args.push_back(arg);
+    //docker_oldexec(docker_id, command);
+    exec(docker, docker_args);
+}
+
+void docker_cp(string docker_id, string source, string target) {
+    // See http://stackoverflow.com/questions/22907231/copying-files-from-host-to-docker-container
+    // Better replace with 'docker cp' of docker 1.8
+    docker_oldexec(docker_id, " /bin/bash -c 'cat > "+target+"' < "+source);
+}
+
+void docker_rm(string docker_id) {
+    exec(docker, {"rm", "-f", docker_id});
+}
+
+int main(int argc, char **argv) {
+    //printf("egid: %d\n", getegid());
+
+    //exec("/usr/bin/id", {});
+    //system("/usr/bin/id");
+
+    if (argc != 2) {
+        usage();
+        return 0;
+    }
+
+    string program=argv[1];
+
+    string docker_id = docker_run("crosbymichael/build-essential", "sleep 1000");
+    // cout << "docker_id: " << docker_id << endl;
+    docker_cp(docker_id, bin_dir+compile_and_run, compile_and_run);
+    docker_cp(docker_id, program, program);
+    docker_exec(docker_id, { "chmod", "700", compile_and_run });
+    docker_exec(docker_id, { "./"+compile_and_run, program});
+    //docker_oldexec(docker_id, "./"+compile_and_run+" "+program);
+    docker_rm(docker_id);
+    cout.flush();
+    return 0;
+}

test~coding~readingCppPrograms.fr/prog.cpp

+#include <iostream>
+#include <fstream>
+using namespace std;
+
+int main() {
+    int x = 1+2;
+    if ( x == 3 ); {
+        cout << "Bonjour!" << endl;
+    }
+    cerr << "Bonjour sur la sortie d'erreur" << endl;
+    cout << "Au revoir." << endl;
+    return 0;
+}