Run command (first test version)

Initially we'll test only in NodeGit with this implementation

Author: AlexaXs

generate/templates/manual/include/run_command.h

@@ -0,0 +1,62 @@
+#ifndef NODEGIT_RUN_CMD_H
+#define NODEGIT_RUN_CMD_H
+
+#include <iostream>
+#include <cstdio>
+#include <iostream>
+#include <stdexcept>
+#include <string>
+#include <array>
+#include "cmd.h"
+
+namespace nodegit {
+  // TODO:
+  // This is just a first testing version to run commands in MacOS, Linux and Win32
+  namespace runcommand {
+    /**
+     * \brief Executes a command.
+     * 
+     * \param cmd object storing all the information needed to execute a command. Result
+     * of the execution will also be stored here.
+     * \return true if command execution succeeded; false otherwise.
+     */
+    bool exec(Cmd *cmd) {
+      // TODO: sanitize path
+      assert (cmd != nullptr);
+      std::string cwd = cmd->GetEnv(Cmd::Env::kCWD);
+      std::string cmdCwd = cwd.empty() ? std::string("") : std::string("cd ").append(cwd).append(" && ");
+      std::string cmdArgs = cmd->Args();
+      std::string finalCmdArgs = cmdArgs.empty() ? std::string("") : std::string(" ").append(cmdArgs);
+      std::string cmdRedirectErr = cmd->GetRedirectStdErr() ? " 2>&1" : std::string("");
+      std::string finalCmd = cmdCwd + cmd->Command() + finalCmdArgs + cmdRedirectErr;
+
+#ifdef WIN32
+      auto pipe = _popen(finalCmd.c_str(), "r");
+#else
+      auto pipe = popen(finalCmd.c_str(), "r");
+#endif
+      if (!pipe) {
+        cmd->errorMsg = "popen() failed!";
+        return false;
+      }
+
+      std::array<char, 128> buffer {};
+      while (!feof(pipe)) {
+        if (fgets(buffer.data(), 128, pipe) != nullptr)
+          cmd->out += buffer.data();
+      }
+#ifdef WIN32
+      auto rc = _pclose(pipe);
+#else
+      auto rc = pclose(pipe);
+#endif
+      
+      if (rc != EXIT_SUCCESS) {
+        cmd->errorMsg = "pclose() failed!";
+        return false;
+      }
+      return true;
+    }
+  } // namespace runcommand
+} // namespace nodegit
+#endif  // NODEGIT_RUN_CMD_H