Improved code readability and added database file argument.

src/fuse_operations.c

@@ -39,20 +39,20 @@
 #include "sourcefs.h"
 #include "ui-socket.h"
 
-// TODO: move this to other file
 const char *get_process_name_by_pid(const int pid) {
   char *name = (char *)calloc(1024, sizeof(char));
   if (name) {
     sprintf(name, "/proc/%d/cmdline", pid);
-    FILE *f = fopen(name, "r");
-    if (f) {
-      size_t size;
-      size = fread(name, sizeof(char), 1024, f);
+    FILE *file = fopen(name, "r");
+    if (file) {
+      size_t size = 0;
+      size = fread(name, sizeof(char), 1024, file);
       if (size > 0) {
-        if ('\n' == name[size - 1])
+        if ('\n' == name[size - 1]) {
           name[size - 1] = '\0';
         }
-      fclose(f);
+      }
+      fclose(file);
     }
   }
   return name;
@@ -70,8 +70,8 @@ static void *xmp_init(struct fuse_conn_info *conn, struct fuse_config *cfg) {
      To make parallel_direct_writes valid, need either set cfg->direct_io
      in current function (recommended in high level API) or set fi->direct_io
      in xmp_create() or xmp_open(). */
-  // cfg->direct_io = 1;
-  // cfg->parallel_direct_writes = 1;
+  cfg->direct_io = 1;
+  cfg->parallel_direct_writes = 1;
 
   /* Pick up changes from lower filesystem right away. This is
      also necessary for better hardlink support. When the kernel
@@ -88,13 +88,13 @@ static void *xmp_init(struct fuse_conn_info *conn, struct fuse_config *cfg) {
 }
 
 static int xmp_getattr(const char *path, struct stat *stbuf,
-                       struct fuse_file_info *fi) {
+                       struct fuse_file_info *file_info) {
   int res;
 
   (void)path;
 
-  if (fi)
-    res = fstat(fi->fh, stbuf);
+  if (file_info)
+    res = fstat(file_info->fh, stbuf);
   else
     res = source_stat(path, stbuf);
   if (res == -1) {
@@ -106,38 +106,39 @@ static int xmp_getattr(const char *path, struct stat *stbuf,
 }
 
 static int xmp_access(const char *path, int mask) {
-  int res;
+  int res = -1;
 
   // if mask is F_OK, then we don't need to check the permissions
   // (is that possible?)
 
   if (mask != F_OK) {
-    struct process_info pi;
-    struct fuse_context *fc = fuse_get_context();
+    struct process_info proc_info;
+    struct fuse_context *context = fuse_get_context();
 
-    pi.PID = fc->pid;
-    pi.name = get_process_name_by_pid(pi.PID);
+    proc_info.PID = context->pid;
+    proc_info.name = get_process_name_by_pid(proc_info.PID);
 
     // fprintf(stderr, "%s, %d\n", path, ask_access(path, pi));
 
-    if (!interactive_access(real_filename(path), pi, 0)) {
-      free(pi.name);
+    if (!interactive_access(real_filename(path), proc_info, 0)) {
+      free((void *)proc_info.name);
       return -EACCES;
     }
 
-    free(pi.name);
+    free((void *)proc_info.name);
   }
 
   res = source_access(path, mask);
 
-  if (res == -1)
+  if (res == -1) {
     return -errno;
+  }
 
   return 0;
 }
 
 static int xmp_readlink(const char *path, char *buf, size_t size) {
-  int res;
+  int res = -1;
 
   res = readlink(path, buf, size - 1);
   if (res == -1)
@@ -264,17 +265,18 @@ static int xmp_mknod(const char *path, mode_t mode, dev_t rdev) {
 */
 
 static int xmp_mkdir(const char *path, mode_t mode) {
-  int res;
+  int res = -1;
 
   res = source_mkdir(path, mode);
-  if (res == -1)
+  if (res == -1) {
     return -errno;
+  }
 
   return 0;
 }
 
 static int xmp_unlink(const char *path) {
-  int res;
+  int res = -1;
   struct process_info pi;
   struct fuse_context *fc = fuse_get_context();
 

src/main.c

@@ -10,16 +10,15 @@
   See the file LICENSE.
 */
 
-#include <sys/types.h>
-#include <unistd.h>
 #define FUSE_USE_VERSION 31
 
 #define _GNU_SOURCE
 
 #include <fuse3/fuse.h>
-
 #include <stdio.h>
 #include <stdlib.h>
+#include <sys/types.h>
+#include <unistd.h>
 
 #include "fuse_operations.h"
 #include "sourcefs.h"
@@ -28,15 +27,25 @@
 const char *mountpoint = NULL;
 
 int main(int argc, char *argv[]) {
+  if (argc < 3) {
+    fprintf(stderr, "Usage: icfs <FUSE arguments> [target directory] [path to "
+                    "the permanent permissions database\n");
+    return EXIT_FAILURE;
+  }
+
+  // if umask != 0, the filesystem will create files with more restrictive
+  // permissions than it's caller reqested
   umask(0);
 
-  int ret = init_ui_socket();
+  // ui socket should always be initialized before anything else, since it
+  // handles the setuid bits!
+  int ret = init_ui_socket(argv[argc - 1]);
   if (ret != 0) {
     fprintf(stderr, "Could not initalize ui-socket.\n");
     exit(EXIT_FAILURE);
   }
 
-  mountpoint = realpath(argv[argc - 1], NULL);
+  mountpoint = realpath(argv[argc - 2], NULL);
 
   ret = source_init(mountpoint);
   if (ret != 0) {
@@ -44,9 +53,9 @@ int main(int argc, char *argv[]) {
     exit(EXIT_FAILURE);
   }
 
-  ret = fuse_main(argc, argv, get_fuse_operations(), NULL);
+  ret = fuse_main(argc - 1, argv, get_fuse_operations(), NULL);
 
-  free(mountpoint);
+  free((void *)mountpoint);
   destroy_ui_socket();
   return ret;
 }

src/ui-socket.c

@@ -22,7 +22,7 @@
 #include <sys/un.h>
 #include <unistd.h>
 
-int init_ui_socket() {
+int init_ui_socket(const char *perm_permissions_db_filename) {
   char line[256];
   FILE *fp;
 
@@ -31,8 +31,7 @@ int init_ui_socket() {
     return 1;
   }
 
-  if (init_perm_permissions_table(
-          "/home/fedir/Developement/uni/ICFS/test/.pt.db")) {
+  if (init_perm_permissions_table(perm_permissions_db_filename)) {
     fprintf(stderr, "Could not initialize permanent permissions table.\n");
     return 1;
   }

src/ui-socket.h

@@ -21,7 +21,7 @@
  *
  * @return: 0 on success, -1 on faliure.
  */
-int init_ui_socket(void);
+int init_ui_socket(const char *perm_permissions_db_filename);
 
 /**
  * Close the GUI communication.