Make systemctl work in flatpak

3 files changed, 39 insertions, 2 deletions

diff --git a/include/Process.hpp b/include/Process.hpp
index 6fd8c31..9662126 100644
--- a/include/Process.hpp
+++ b/include/Process.hpp
@@ -17,5 +17,9 @@ namespace gsr {
     pid_t exec_program(const char **args, int *read_fd);
     // Arguments ending with NULL. Returns the exit status of the program or -1 on error
     int exec_program_get_stdout(const char **args, std::string &result);
+    // Arguments ending with NULL. Returns the exit status of the program or -1 on error.
+    // This works the same as |exec_program_get_stdout|, except on flatpak where this runs the program on the
+    // host machine with flatpak-spawn --host
+    int exec_program_on_host_get_stdout(const char **args, std::string &result);
     pid_t pidof(const char *process_name);
 }
\ No newline at end of file
diff --git a/src/Process.cpp b/src/Process.cpp
index 2a704de..347c485 100644
--- a/src/Process.cpp
+++ b/src/Process.cpp
@@ -31,6 +31,15 @@ namespace gsr {
         return true;
     }
 
+    static int count_num_args(const char **args) {
+        int num_args = 0;
+        while(*args) {
+            ++num_args;
+            ++args;
+        }
+        return num_args;
+    }
+
     bool exec_program_daemonized(const char **args) {
         /* 1 argument */
         if(args[0] == nullptr)
@@ -143,6 +152,30 @@ namespace gsr {
         return exit_status;
     }
 
+    int exec_program_on_host_get_stdout(const char **args, std::string &result) {
+        if(count_num_args(args) > 64 - 3) {
+            fprintf(stderr, "Error: too many arguments when trying to launch \"%s\"\n", args[0]);
+            return -1;
+        }
+
+        const bool inside_flatpak = getenv("FLATPAK_ID") != NULL;
+        if(inside_flatpak) {
+            // Assumes programs wont need more than 64 - 3 args
+            const char *modified_args[64] = { "flatpak-spawn", "--host", "--" };
+            for(int i = 3; i < 64; ++i) {
+                const char *arg = args[i - 3];
+                if(!arg) {
+                    modified_args[i] = nullptr;
+                    break;
+                }
+                modified_args[i] = arg;
+            }
+            return exec_program_get_stdout(modified_args, result);
+        } else {
+            return exec_program_get_stdout(args, result);
+        }
+    }
+
     // |output_buffer| should be at least PATH_MAX in size
     bool read_cmdline_arg0(const char *filepath, char *output_buffer, int output_buffer_size) {
         output_buffer[0] = '\0';
diff --git a/src/gui/GlobalSettingsPage.cpp b/src/gui/GlobalSettingsPage.cpp
index 9b927f0..7e79c16 100644
--- a/src/gui/GlobalSettingsPage.cpp
+++ b/src/gui/GlobalSettingsPage.cpp
@@ -77,7 +77,7 @@ namespace gsr {
 
             const char *args[] = { "systemctl", enable ? "enable" : "disable", "--user", "gpu-screen-recorder-ui", nullptr };
             std::string stdout_str;
-            const int exit_status = exec_program_get_stdout(args, stdout_str);
+            const int exit_status = exec_program_on_host_get_stdout(args, stdout_str);
             if(on_startup_changed)
                 on_startup_changed(enable, exit_status);
         };
@@ -109,7 +109,7 @@ namespace gsr {
 
         const char *args[] = { "systemctl", "is-enabled", "--quiet", "--user", "gpu-screen-recorder-ui", nullptr };
         std::string stdout_str;
-        const int exit_status = exec_program_get_stdout(args, stdout_str);
+        const int exit_status = exec_program_on_host_get_stdout(args, stdout_str);
         startup_radio_button_ptr->set_selected_item(exit_status == 0 ? "start_on_system_startup" : "dont_start_on_system_startup", false, false);
     }