Skeleton for the process tables implementation

Wrote a skeleton for the future process table implemntation. Aslo
slightly edited the ui-socket interface.

src/fuse_operations.c

@@ -264,7 +264,7 @@ static int xmp_unlink(const char *path) {
 
   // fprintf(stderr, "%s, %d\n", path, ask_access(path, pi));
 
-  if (ask_access(real_filename(path), pi)) {
+  if (interactive_access(real_filename(path), pi)) {
     free(pi.name);
     return -EACCES;
   }
@@ -392,7 +392,7 @@ static int xmp_create(const char *path, mode_t mode,
 
   // fprintf(stderr, "%s, %d\n", path, ask_access(path, pi));
 
-  if (ask_access(real_filename(path), pi)) {
+  if (interactive_access(real_filename(path), pi)) {
     free(pi.name);
     return -EACCES;
   }
@@ -417,7 +417,7 @@ static int xmp_open(const char *path, struct fuse_file_info *fi) {
   pi.name = get_process_name_by_pid(pi.PID);
 
   // fprintf(stderr, "%s, %d\n", path, ask_access(path, pi));
-  if (ask_access(real_filename(path), pi)) {
+  if (interactive_access(real_filename(path), pi)) {
     free(pi.name);
     return -EACCES;
   }

src/ui-socket.c

@@ -37,6 +37,9 @@ int init_ui_socket(const char *filename) {
 }
 
 /**
+ * Asks the user if the process should be allowed to access the file using the
+ * GUI
+ *
  * @param filename: The file that the process is trying to access
  * @pram pi: The process information
  * @return: 0 if access is denied, 1 if access is allowed, 2 if access is allwed
@@ -77,3 +80,66 @@ int ask_access(const char *filename, struct process_info pi) {
   int zenity_exit_code = WEXITSTATUS(pclose(fp));
   return zenity_exit_code;
 }
+
+/**
+ * Checks if the process has a temporary access to the file.
+ *
+ * @param filename: The file that the process is trying to access
+ * @pram pi: The process information
+ * @return: 0 if access is denied, 1 if access is allowed
+ */
+int check_temp_access(const char *filename, struct process_info pi) {
+  perror("Not implemented");
+  return 0;
+}
+
+/**
+ * Checks if the process has a permanent access to the file.
+ *
+ * @param filename: The file that the process is trying to access
+ * @pram pi: The process information
+ * @return: 0 if access is denied, 1 if access is allowed
+ */
+int check_perm_access(const char *filename, struct process_info pi) {
+  perror("Not implemented");
+  return 0;
+}
+
+void give_temp_access(const char *filename, struct process_info pi) {
+  perror("Not implemented");
+}
+void give_perm_access(const char *filename, struct process_info pi) {
+  perror("Not implemented");
+}
+
+/**
+ * Check access according to:
+ * 1. temp permission table
+ * 2. permanent permission table
+ * 3. user descision
+ *
+ * @param filename: The file that the process is trying to access
+ * @pram pi: The process information
+ * @return: 0 if access is denied, 1 if access is allowed
+ */
+int interactive_access(const char *filename, struct process_info pi) {
+
+  if (check_temp_access(filename, pi) || check_perm_access(filename, pi)) {
+    // access was already granted before
+    return 1;
+  }
+
+  int user_response = ask_access(filename, pi);
+  if (user_response == 1) {
+    // user said "yes"
+    give_perm_access(filename, pi);
+    return 1;
+  } else if (user_response == 2) {
+    // user said "yes, but only this time"
+    give_temp_access(filename, pi);
+    return 1;
+  }
+
+  // otherwise "no"
+  return 0;
+}

src/ui-socket.h

@@ -24,6 +24,6 @@ struct process_info {
 // For default socket location, set socket_path = NULL.
 int init_ui_socket(const char *socket_path);
 
-int ask_access(const char *filename, struct process_info pi);
+int interactive_access(const char *filename, struct process_info pi);
 
 #endif // !UI_SOCKET_H