diff --git a/Makefile b/Makefile
index 8e801b9..4c39f81 100644
--- a/Makefile
+++ b/Makefile
@@ -13,6 +13,8 @@ OBJ_FILES := $(patsubst %.c,$(BD)/%.o,$(SRC_FILES))
 OBJ_FILES := $(patsubst %.c,$(BD)/%.o,$(SRC_FILES))
 SHARED_OBJ_FILES := $(patsubst %.c,$(SBD)/%.o,$(SRC_FILES))
 
+CFLAGS ?= -O2 -ansi -pedantic
+
 shared: $(SBD)/$(SHARED_LIB)
 static: $(BD)/$(STATIC_LIB)
 
diff --git a/src/drivers/unix_fs/unix_fs_driver.c b/src/drivers/unix_fs/unix_fs_driver.c
index fbf81aa..860be61 100644
--- a/src/drivers/unix_fs/unix_fs_driver.c
+++ b/src/drivers/unix_fs/unix_fs_driver.c
@@ -84,6 +84,43 @@ deserialize_header(int fd, CommentHeader *header)
 
 /* TODO: validate driver_data_ptr */
 
+FILE *
+acquire_id_ctrl_file(char *id_ctrl_file_path)
+{
+    FILE *retval;
+    int fd;
+
+    retval = NULL;
+    
+    if (!(retval = fopen(id_ctrl_file_path, "r+"))) {
+        goto defer;
+    }
+
+    fd = fileno(retval);
+    
+    if (lockf(fd, F_LOCK, 0) < 0) {
+        fclose(retval);
+        retval = NULL;
+        goto defer;
+    }
+
+defer:
+    return retval;
+}
+
+int
+release_id_ctrl_file(FILE *id_ctrl_file)
+{
+    int fd;
+
+    fd = fileno(id_ctrl_file);
+    if (lockf(fd, F_ULOCK, 0) < 0) {
+        fclose(id_ctrl_file);
+        return -ENOLCK;
+    }
+    return fclose(id_ctrl_file);
+}
+
 int
 unix_fs_driver_leave_comment(void *driver_data_ptr, const CommentHeader *header, const char *text)
 {
@@ -114,21 +151,11 @@ unix_fs_driver_leave_comment(void *driver_data_ptr, const CommentHeader *header,
         goto defer;
     }
 
-    id_ctrl_file = fopen(id_ctrl_file_path, "r+");
-
-    if (!id_ctrl_file) {
+    if (!(id_ctrl_file = acquire_id_ctrl_file(id_ctrl_file_path))) {
         retval = -EIO;
         goto defer;
     }
 
-    id_ctrl_fd = fileno(id_ctrl_file);
-    
-    if (lockf(id_ctrl_fd, F_LOCK, 0) < 0) {
-        id_ctrl_fd = -1;
-        retval = -EIO;
-        goto defer;
-    }
-    
     if (fscanf(id_ctrl_file, "%d", &max_id) != 1) {
         max_id = 1;
     }
@@ -161,22 +188,18 @@ unix_fs_driver_leave_comment(void *driver_data_ptr, const CommentHeader *header,
     if (retval < 0) {
         goto defer;
     }
-    
-    if (!(id_ctrl_file = freopen(id_ctrl_file_path, "w+", id_ctrl_file))) {
-        retval = -EIO;
-        goto defer;
-    }
+
+    rewind(id_ctrl_file);
     
     fprintf(id_ctrl_file, "%d", max_id + 1); /* update id only on success */
     retval = max_id + 1;
 defer:
-    if (id_ctrl_fd >= 0) {
-        if (lockf(id_ctrl_fd, F_ULOCK, 0) < 0) {
-            fprintf(stderr, "Failed to release id control lock, aborting...\n");
+    if (id_ctrl_file) {
+        if (release_id_ctrl_file(id_ctrl_file) < 0) {
+            fprintf(stderr, "Failed to release id control file, aborting...\n");
             abort();
         }
     }
-    if (id_ctrl_file) fclose(id_ctrl_file);
     free(id_ctrl_file_path);
     free(header_file_path);
     free(text_file_path);