From 6a2ef269f37820db40b0d1cd19d7fdb7696c0d2a Mon Sep 17 00:00:00 2001 From: Serhii Kostiuk Date: Thu, 9 Apr 2020 16:43:06 +0300 Subject: Execute system commands without invoking system shell Changes after a code review: - fixed documentation for the closeBackground function - renamed ```app``` parameter to ```cmd``` --- include/mts/MTS_System.h | 16 +++++++--------- src/MTS_System.cpp | 18 +++++++++--------- 2 files changed, 16 insertions(+), 18 deletions(-) diff --git a/include/mts/MTS_System.h b/include/mts/MTS_System.h index 6bca21b..cd9b9dd 100644 --- a/include/mts/MTS_System.h +++ b/include/mts/MTS_System.h @@ -71,12 +71,12 @@ namespace MTS { * A safer alternative to System::cmd that allows to execute applications with controlled * list of arguments bypasing the system shell. * - * \param app name of the application to be executed + * \param cmd name of the application to be executed * \param argv vector of arguments (excluding argument zero) * \param result stdout output from the application is stored here * \return result code as for std::system and UNIX pclose */ - static int32_t execute(const std::string& app, const std::vector& argv, std::string& result); + static int32_t execute(const std::string& cmd, const std::vector& argv, std::string& result); //! Spawn a process and open pipe with the specified type (READ or WRITE) /*! @@ -84,18 +84,16 @@ namespace MTS { * list of arguments bypasing the system shell. If succeded, information about the spawned * process is written to the \p child structure. * - * \param app name of the application to be executed + * \param cmd name of the application to be executed * \param argv vector of arguments (excluding argument zero) * \param type open pipe for read from child or write to child * \return true on success, false on failure */ - static bool executeBackground(const std::string& app, const std::vector& argv, PipeType type, ChildHandle& child); + static bool executeBackground(const std::string& cmd, const std::vector& argv, PipeType type, ChildHandle& child); //! Close the pipe and wait for a child to finish execution /*! - * \param child name of the application to be executed - * \param argv vector of arguments (excluding argument zero) - * \param result stdout output from the application is stored here + * \param child structure with child process information as populated by executeBackground * \return result code as for std::system and UNIX pclose */ static int closeBackground(ChildHandle& child); @@ -103,13 +101,13 @@ namespace MTS { private: //! Spawn a process and open pipe with the specified type (READ or WRITE) - static bool executeBackground(const std::string& app, char* const argv[], PipeType type, ChildHandle& child); + static bool executeBackground(const std::string& cmd, char* const argv[], PipeType type, ChildHandle& child); //! Utility method. Cast argument to a C pointer required by some C-style functions. static inline char* castArgument(const std::string& arg); //! Utility method. Convert argument vector to a format required by execve and posix_spawn. - static std::vector castArgVector(const std::string& app, const std::vector& argv); + static std::vector castArgVector(const std::string& cmd, const std::vector& argv); //! Lightweight C++ wrapper with auto-close for file descriptors class FdWrapper { diff --git a/src/MTS_System.cpp b/src/MTS_System.cpp index 6acf065..31976e1 100644 --- a/src/MTS_System.cpp +++ b/src/MTS_System.cpp @@ -172,7 +172,7 @@ int32_t System::readFile(const std::string& path, std::string& result) { return 0; } -int32_t System::execute(const std::string& app, const std::vector& argv, std::string& result) { +int32_t System::execute(const std::string& cmd, const std::vector& argv, std::string& result) { // Ported directly from System::cmd std::string output; const int max_buffer = 256; @@ -180,7 +180,7 @@ int32_t System::execute(const std::string& app, const std::vector& int32_t code = -1; ChildHandle child; - if (executeBackground(app, argv, PipeType::READ, child)) { + if (executeBackground(cmd, argv, PipeType::READ, child)) { while (!feof(child.stream)) { if (fgets(buffer, max_buffer, child.stream) != NULL) { output.append(buffer); @@ -194,9 +194,9 @@ int32_t System::execute(const std::string& app, const std::vector& return code; } -bool System::executeBackground(const std::string& app, const std::vector& argv, System::PipeType type, System::ChildHandle& child) { - std::vector arguments = castArgVector(app, argv); - return executeBackground(app, arguments.data(), type, child); +bool System::executeBackground(const std::string& cmd, const std::vector& argv, System::PipeType type, System::ChildHandle& child) { + std::vector arguments = castArgVector(cmd, argv); + return executeBackground(cmd, arguments.data(), type, child); } int System::closeBackground(System::ChildHandle& child) { @@ -212,7 +212,7 @@ int System::closeBackground(System::ChildHandle& child) { return pstat; } -bool System::executeBackground(const std::string& app, char* const argv[], System::PipeType type, ChildHandle& child) { +bool System::executeBackground(const std::string& cmd, char* const argv[], System::PipeType type, ChildHandle& child) { pid_t childPid; FILE* stream = NULL; posix_spawn_file_actions_t actions; @@ -262,7 +262,7 @@ bool System::executeBackground(const std::string& app, char* const argv[], Syste break; } - if (posix_spawnp(&childPid, app.c_str(), &actions, NULL, argv, NULL) != 0) { + if (posix_spawnp(&childPid, cmd.c_str(), &actions, NULL, argv, NULL) != 0) { // failed to spawn the process break; } @@ -294,11 +294,11 @@ char* System::castArgument(const std::string& arg) { return const_cast(arg.c_str()); } -std::vector System::castArgVector(const std::string& app, const std::vector& argv) { +std::vector System::castArgVector(const std::string& cmd, const std::vector& argv) { std::vector result; // Append application name as argument zero - result.push_back(castArgument(app)); + result.push_back(castArgument(cmd)); // Append all other arguments for (const std::string& arg : argv) { -- cgit v1.2.3