Userland: Rely on a single authoritative source for the default PATH

Author: https://github.com/timschumi
Commit: https://github.com/SerenityOS/serenity/commit/39a3775f48
Pull-request: https://github.com/SerenityOS/serenity/pull/14941
Reviewed-by: https://github.com/linusg

Userland/Applications/Terminal/main.cpp

@@ -11,6 +11,7 @@
 #include <LibConfig/Listener.h>
 #include <LibCore/ArgsParser.h>
 #include <LibCore/DirIterator.h>
+#include <LibCore/File.h>
 #include <LibCore/System.h>
 #include <LibDesktop/Launcher.h>
 #include <LibGUI/Action.h>
@@ -162,7 +163,7 @@ static ErrorOr<void> run_command(String command, bool keep_open)
         arguments.append("-c"sv);
         arguments.append(command);
     }
-    auto env = TRY(FixedArray<StringView>::try_create({ "TERM=xterm"sv, "PAGER=more"sv, "PATH=/usr/local/sbin:/usr/local/bin:/usr/bin:/bin"sv }));
+    auto env = TRY(FixedArray<StringView>::try_create({ "TERM=xterm"sv, "PAGER=more"sv, "PATH="sv DEFAULT_PATH_SV }));
     TRY(Core::System::exec(shell, arguments, Core::System::SearchInPath::No, env.span()));
     VERIFY_NOT_REACHED();
 }

Userland/DevTools/HackStudio/main.cpp

@@ -128,7 +128,7 @@ static void update_path_environment_variable()
 
     if (path.length())
         path.append(':');
-    path.append("/usr/local/sbin:/usr/local/bin:/usr/bin:/bin"sv);
+    path.append(DEFAULT_PATH_SV);
     setenv("PATH", path.to_string().characters(), true);
 }
 

Userland/Libraries/LibC/unistd.cpp

@@ -8,6 +8,7 @@
 #include <AK/ScopedValueRollback.h>
 #include <AK/String.h>
 #include <AK/Vector.h>
+#include <LibCore/File.h>
 #include <alloca.h>
 #include <assert.h>
 #include <bits/pthread_cancel.h>
@@ -186,7 +187,7 @@ int execvpe(char const* filename, char* const argv[], char* const envp[])
     ScopedValueRollback errno_rollback(errno);
     String path = getenv("PATH");
     if (path.is_empty())
-        path = "/bin:/usr/bin";
+        path = DEFAULT_PATH;
     auto parts = path.split(':');
     for (auto& part : parts) {
         auto candidate = String::formatted("{}/{}", part, filename);

Userland/Libraries/LibCore/File.h

@@ -11,6 +11,10 @@
 #include <LibCore/IODevice.h>
 #include <sys/stat.h>
 
+// FIXME: Make this a bit prettier.
+#define DEFAULT_PATH "/usr/local/sbin:/usr/local/bin:/usr/bin:/bin"
+#define DEFAULT_PATH_SV "/usr/local/sbin:/usr/local/bin:/usr/bin:/bin"sv
+
 namespace Core {
 
 class File final : public IODevice {

Userland/Libraries/LibCore/System.cpp

@@ -958,7 +958,7 @@ ErrorOr<String> find_file_in_path(StringView filename)
     auto const* path_ptr = getenv("PATH");
     StringView path { path_ptr, strlen(path_ptr) };
     if (path.is_empty())
-        path = "/bin:/usr/bin"sv;
+        path = DEFAULT_PATH_SV;
     auto parts = path.split_view(':');
     for (auto& part : parts) {
         auto candidate = String::formatted("{}/{}", part, filename);
@@ -1043,7 +1043,7 @@ ErrorOr<void> exec(StringView filename, Span<StringView> arguments, SearchInPath
             ScopedValueRollback errno_rollback(errno);
             String path = getenv("PATH");
             if (path.is_empty())
-                path = "/bin:/usr/bin";
+                path = DEFAULT_PATH;
             auto parts = path.split(':');
             for (auto& part : parts) {
                 auto candidate = String::formatted("{}/{}", part, filename);

Userland/Services/TelnetServer/main.cpp

@@ -10,6 +10,7 @@
 #include <AK/Types.h>
 #include <LibCore/ArgsParser.h>
 #include <LibCore/EventLoop.h>
+#include <LibCore/File.h>
 #include <LibCore/TCPServer.h>
 #include <LibMain/Main.h>
 #include <fcntl.h>
@@ -71,7 +72,7 @@ static void run_command(int ptm_fd, String command)
             args[1] = "-c";
             args[2] = command.characters();
         }
-        char const* envs[] = { "TERM=xterm", "PATH=/usr/local/sbin:/usr/local/bin:/usr/bin:/bin", nullptr };
+        char const* envs[] = { "TERM=xterm", "PATH=" DEFAULT_PATH, nullptr };
         rc = execve("/bin/Shell", const_cast<char**>(args), const_cast<char**>(envs));
         if (rc < 0) {
             perror("execve");

Userland/Shell/Shell.cpp

@@ -2189,7 +2189,7 @@ Shell::Shell()
             path.append({ path_env_ptr, strlen(path_env_ptr) });
         if (path.length())
             path.append(":"sv);
-        path.append("/usr/local/sbin:/usr/local/bin:/usr/bin:/bin"sv);
+        path.append(DEFAULT_PATH_SV);
         setenv("PATH", path.to_string().characters(), true);
     }