Skip to content

Commit

Permalink
Everywhere: Replace some uses of fork/exec with posix_spawn
Browse files Browse the repository at this point in the history
It's less code, and it's potentially more efficient once
posix_spawn is a real syscall.
  • Loading branch information
nico authored and awesomekling committed Jun 29, 2020
1 parent 301ac3c commit 12cbc4a
Show file tree
Hide file tree
Showing 11 changed files with 65 additions and 101 deletions.
27 changes: 11 additions & 16 deletions Applications/FileManager/main.cpp
Original file line number Diff line number Diff line change
Expand Up @@ -58,6 +58,7 @@
#include <LibGUI/Window.h>
#include <LibGfx/Palette.h>
#include <signal.h>
#include <spawn.h>
#include <stdio.h>
#include <string.h>
#include <unistd.h>
Expand Down Expand Up @@ -337,16 +338,13 @@ int run_in_windowed_mode(RefPtr<Core::ConfigFile> config, String initial_locatio
});

auto open_terminal_action = GUI::Action::create("Open Terminal here...", Gfx::Bitmap::load_from_file("/res/icons/16x16/app-terminal.png"), [&](const GUI::Action&) {
if (!fork()) {
if (chdir(directory_view.path().characters()) < 0) {
perror("chdir");
exit(1);
}

if (execl("/bin/Terminal", "Terminal", nullptr) < 0)
perror("execl");
exit(1);
}
posix_spawn_file_actions_t spawn_actions;
posix_spawn_file_actions_init(&spawn_actions);
posix_spawn_file_actions_addchdir(&spawn_actions, directory_view.path().characters());
pid_t pid;
const char* argv[] = { "Terminal", nullptr };
posix_spawn(&pid, "/bin/Terminal", &spawn_actions, nullptr, const_cast<char**>(argv), environ);
posix_spawn_file_actions_destroy(&spawn_actions);
});

RefPtr<GUI::Action> view_as_table_action;
Expand Down Expand Up @@ -719,13 +717,10 @@ int run_in_windowed_mode(RefPtr<Core::ConfigFile> config, String initial_locatio
};

auto open_in_text_editor_action = GUI::Action::create("Open in TextEditor...", Gfx::Bitmap::load_from_file("/res/icons/TextEditor16.png"), [&](auto&) {
pid_t child;
for (auto& path : selected_file_paths()) {
if (!fork()) {
int rc = execl("/bin/TextEditor", "TextEditor", path.characters(), nullptr);
if (rc < 0)
perror("execl");
exit(1);
}
const char* argv[] = { "TextEditor", path.characters(), nullptr };
posix_spawn(&child, "/bin/TextEditor", nullptr, nullptr, const_cast<char**>(argv), environ);
}
});

Expand Down
15 changes: 5 additions & 10 deletions Applications/KeyboardSettings/main.cpp
Original file line number Diff line number Diff line change
Expand Up @@ -40,6 +40,7 @@
#include <LibGUI/MessageBox.h>
#include <LibGUI/WindowServerConnection.h>
#include <LibKeyboard/CharacterMap.h>
#include <spawn.h>

int main(int argc, char** argv)
{
Expand Down Expand Up @@ -123,18 +124,12 @@ int main(int argc, char** argv)
GUI::MessageBox::show("Please select character mapping file.", "Keyboard settings", GUI::MessageBox::Type::Error, GUI::MessageBox::InputType::OK, window);
return;
}

pid_t child_pid = fork();
if (child_pid < 0) {
perror("fork");
pid_t child_pid;
const char* argv[] = { "/bin/keymap", character_map_file.characters(), nullptr };
if ((errno = posix_spawn(&child_pid, "/bin/keymap", nullptr, nullptr, const_cast<char**>(argv), environ))) {
perror("posix_spawn");
exit(1);
}
if (child_pid == 0) {
if (execl("/bin/keymap", "/bin/keymap", character_map_file.characters(), nullptr) < 0) {
perror("execl");
exit(1);
}
}
if (quit)
app.quit();
};
Expand Down
8 changes: 4 additions & 4 deletions Applications/QuickShow/main.cpp
Original file line number Diff line number Diff line change
Expand Up @@ -44,6 +44,7 @@
#include <LibGfx/Bitmap.h>
#include <LibGfx/Palette.h>
#include <LibGfx/Rect.h>
#include <spawn.h>
#include <stdio.h>
#include <string.h>

Expand Down Expand Up @@ -110,11 +111,10 @@ int main(int argc, char** argv)
widget.load_from_file(url.path());
}

pid_t child;
for (size_t i = 1; i < urls.size(); ++i) {
if (fork() == 0) {
execl("/bin/QuickShow", "/bin/QuickShow", urls[i].path().characters(), nullptr);
ASSERT_NOT_REACHED();
}
const char* argv[] = { "/bin/QuickShow", urls[i].path().characters(), nullptr };
posix_spawn(&child, "/bin/QuickShow", nullptr, nullptr, const_cast<char**>(argv), environ);
}
}
};
Expand Down
8 changes: 4 additions & 4 deletions Applications/Terminal/main.cpp
Original file line number Diff line number Diff line change
Expand Up @@ -47,6 +47,7 @@
#include <fcntl.h>
#include <pwd.h>
#include <signal.h>
#include <spawn.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
Expand Down Expand Up @@ -257,10 +258,9 @@ int main(int argc, char** argv)

auto& app_menu = menubar->add_menu("Terminal");
app_menu.add_action(GUI::Action::create("Open new terminal", { Mod_Ctrl | Mod_Shift, Key_N }, Gfx::Bitmap::load_from_file("/res/icons/16x16/app-terminal.png"), [&](auto&) {
if (!fork()) {
execl("/bin/Terminal", "Terminal", nullptr);
exit(1);
}
pid_t child;
const char* argv[] = { "Terminal", nullptr };
posix_spawn(&child, "/bin/Terminal", nullptr, nullptr, const_cast<char**>(argv), environ);
}));
app_menu.add_action(GUI::Action::create("Settings...", Gfx::Bitmap::load_from_file("/res/icons/gear16.png"),
[&](const GUI::Action&) {
Expand Down
13 changes: 5 additions & 8 deletions DevTools/HackStudio/main.cpp
Original file line number Diff line number Diff line change
Expand Up @@ -71,6 +71,7 @@
#include <LibThread/Lock.h>
#include <LibThread/Thread.h>
#include <LibVT/TerminalWidget.h>
#include <spawn.h>
#include <stdio.h>
#include <sys/wait.h>
#include <unistd.h>
Expand Down Expand Up @@ -766,15 +767,11 @@ void open_file(const String& filename)

bool make_is_available()
{
auto pid = fork();
if (pid < 0)
pid_t pid;
const char* argv[] = { "make", "--version", nullptr };
if ((errno = posix_spawnp(&pid, "make", nullptr, nullptr, const_cast<char**>(argv), environ))) {
perror("posix_spawn");
return false;

if (!pid) {
int rc = execlp("make", "make", "--version", nullptr);
ASSERT(rc < 0);
perror("execl");
exit(127);
}

int wstatus;
Expand Down
13 changes: 4 additions & 9 deletions Libraries/LibC/stdlib.cpp
Original file line number Diff line number Diff line change
Expand Up @@ -36,6 +36,7 @@
#include <ctype.h>
#include <errno.h>
#include <signal.h>
#include <spawn.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
Expand Down Expand Up @@ -706,16 +707,10 @@ int system(const char* command)
if (!command)
return 1;

auto child = fork();
if (child < 0)
pid_t child;
const char* argv[] = { "sh", "-c", command, nullptr };
if ((errno = posix_spawn(&child, "/bin/sh", nullptr, nullptr, const_cast<char**>(argv), environ)))
return -1;

if (!child) {
int rc = execl("/bin/sh", "sh", "-c", command, nullptr);
ASSERT(rc < 0);
perror("execl");
exit(127);
}
int wstatus;
waitpid(child, &wstatus, 0);
return WEXITSTATUS(wstatus);
Expand Down
13 changes: 5 additions & 8 deletions MenuApplets/ResourceGraph/main.cpp
Original file line number Diff line number Diff line change
Expand Up @@ -35,6 +35,7 @@
#include <LibGUI/Painter.h>
#include <LibGUI/Window.h>
#include <LibGfx/Palette.h>
#include <spawn.h>
#include <stdio.h>

enum class GraphType {
Expand Down Expand Up @@ -106,14 +107,10 @@ class GraphWidget final : public GUI::Frame {
{
if (event.button() != GUI::MouseButton::Left)
return;
pid_t pid = fork();
if (pid < 0) {
perror("fork");
} else if (pid == 0) {
execl("/bin/SystemMonitor", "SystemMonitor", nullptr);
perror("execl");
ASSERT_NOT_REACHED();
}
pid_t child_pid;
const char* argv[] = { "SystemMonitor", nullptr };
if ((errno = posix_spawn(&child_pid, "/bin/SystemMonitor", nullptr, nullptr, const_cast<char**>(argv), environ)))
perror("posix_spawn");
}

static void get_cpu_usage(unsigned& busy, unsigned& idle)
Expand Down
15 changes: 5 additions & 10 deletions Services/LaunchServer/Launcher.cpp
Original file line number Diff line number Diff line change
Expand Up @@ -29,6 +29,7 @@
#include <AK/LexicalPath.h>
#include <LibCore/ConfigFile.h>
#include <LibCore/DirIterator.h>
#include <spawn.h>
#include <stdio.h>
#include <sys/stat.h>

Expand Down Expand Up @@ -125,18 +126,12 @@ bool Launcher::open_with_handler_name(const URL& url, const String& handler_name

bool spawn(String executable, String argument)
{
pid_t child_pid = fork();
if (child_pid < 0) {
perror("fork");
pid_t child_pid;
const char* argv[] = { executable.characters(), argument.characters(), nullptr };
if ((errno = posix_spawn(&child_pid, executable.characters(), nullptr, nullptr, const_cast<char**>(argv), environ))) {
perror("posix_spawn");
return false;
}
if (child_pid == 0) {
if (execl(executable.characters(), executable.characters(), argument.characters(), nullptr) < 0) {
perror("execl");
return false;
}
ASSERT_NOT_REACHED();
}
return true;
}

Expand Down
25 changes: 11 additions & 14 deletions Services/SystemMenu/main.cpp
Original file line number Diff line number Diff line change
Expand Up @@ -36,6 +36,7 @@
#include <LibGUI/Menu.h>
#include <LibGUI/WindowServerConnection.h>
#include <LibGfx/Bitmap.h>
#include <spawn.h>

//#define SYSTEM_MENU_DEBUG

Expand Down Expand Up @@ -149,12 +150,11 @@ NonnullRefPtr<GUI::Menu> build_system_menu()
auto parent_menu = g_app_category_menus.get(app.category).value_or(*system_menu);
parent_menu->add_action(GUI::Action::create(app.name, icon.ptr(), [app_identifier](auto&) {
dbg() << "Activated app with ID " << app_identifier;
if (fork() == 0) {
const auto& bin = g_apps[app_identifier].executable;
if (execl(bin.characters(), bin.characters(), nullptr) < 0)
perror("execl");
ASSERT_NOT_REACHED();
}
const auto& bin = g_apps[app_identifier].executable;
pid_t child_pid;
const char* argv[] = { bin.characters(), nullptr };
if ((errno = posix_spawn(&child_pid, bin.characters(), nullptr, nullptr, const_cast<char**>(argv), environ)))
perror("posix_spawn");
}));
++app_identifier;
}
Expand Down Expand Up @@ -197,10 +197,9 @@ NonnullRefPtr<GUI::Menu> build_system_menu()

system_menu->add_separator();
system_menu->add_action(GUI::Action::create("About...", Gfx::Bitmap::load_from_file("/res/icons/16x16/ladybug.png"), [](auto&) {
if (fork() == 0) {
execl("/bin/About", "/bin/About", nullptr);
ASSERT_NOT_REACHED();
}
pid_t child_pid;
const char* argv[] = { "/bin/About", nullptr };
posix_spawn(&child_pid, "/bin/About", nullptr, nullptr, const_cast<char**>(argv), environ);
}));
system_menu->add_separator();
system_menu->add_action(GUI::Action::create("Exit...", [](auto&) {
Expand All @@ -209,10 +208,8 @@ NonnullRefPtr<GUI::Menu> build_system_menu()
if (command.size() == 0)
return;

if (fork() == 0) {
execv(command[0], const_cast<char* const*>(command.data()));
ASSERT_NOT_REACHED();
}
pid_t child_pid;
posix_spawn(&child_pid, command[0], nullptr, nullptr, const_cast<char**>(command.data()), environ);
}));

return system_menu;
Expand Down
12 changes: 6 additions & 6 deletions Userland/flock.cpp
Original file line number Diff line number Diff line change
Expand Up @@ -24,6 +24,7 @@
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/

#include <spawn.h>
#include <stdio.h>
#include <stdlib.h>
#include <sys/wait.h>
Expand All @@ -36,15 +37,14 @@ int main(int argc, char** argv)
return 0;
}

if (!fork()) {
if (execvp(argv[2], &argv[2]) < 0) {
perror("execvp");
exit(1);
}
pid_t child_pid;
if ((errno = posix_spawnp(&child_pid, argv[2], nullptr, nullptr, &argv[2], environ))) {
perror("posix_spawn");
return 1;
}

int status;
if (waitpid(-1, &status, 0) < 0) {
if (waitpid(child_pid, &status, 0) < 0) {
perror("waitpid");
return 1;
}
Expand Down
17 changes: 5 additions & 12 deletions Userland/userdel.cpp
Original file line number Diff line number Diff line change
Expand Up @@ -31,6 +31,7 @@
#include <dirent.h>
#include <errno.h>
#include <pwd.h>
#include <spawn.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
Expand Down Expand Up @@ -121,20 +122,12 @@ int main(int argc, char** argv)
}

if (access(home_directory.characters(), F_OK) != -1) {
auto child = fork();

if (child < 0) {
perror("fork");
pid_t child;
const char* argv[] = { "rm", "-r", home_directory.characters(), nullptr };
if ((errno = posix_spawn(&child, "/bin/rm", nullptr, nullptr, const_cast<char**>(argv), environ))) {
perror("posix_spawn");
return 12;
}

if (!child) {
int rc = execl("/bin/rm", "rm", "-r", home_directory.characters(), nullptr);
ASSERT(rc < 0);
perror("execl");
exit(127);
}

int wstatus;
if (waitpid(child, &wstatus, 0) < 0) {
perror("waitpid");
Expand Down

0 comments on commit 12cbc4a

Please sign in to comment.