Merge branch 'feature/system-calls' into 'josh/22-read-syscall'

# Conflicts:
#   userprog/syscall.c
#   userprog/system_calls.h

Makefile.build

@@ -68,6 +68,7 @@ userprog_SRC += userprog/syscall_open.c
 userprog_SRC += userprog/syscall_halt.c
 userprog_SRC += userprog/syscall_wait.c
 userprog_SRC += userprog/syscall_create.c
+userprog_SRC += userprog/syscall_remove.c
 userprog_SRC += userprog/syscall_write.c
 userprog_SRC += userprog/file_descriptors_map.c
 userprog_SRC += userprog/syscall_read.c

userprog/syscall.c

@@ -70,6 +70,9 @@ syscall_handler (struct intr_frame *f UNUSED)
   case SYSCALL_CREATE:
     syscall_create(f);
 	break;
+  case SYSCALL_REMOVE:
+	syscall_remove(f);
+	break;
   case SYSCALL_WRITE:
     syscall_write(f);
     break;
@@ -79,6 +82,9 @@ syscall_handler (struct intr_frame *f UNUSED)
   case SYSCALL_READ:
     syscall_read(f);
     break;
+  case SYSCALL_FILESIZE:
+	syscall_filesize(f);
+	break;
   default:
     printf ("WARNING: Invalid Syscall (%d)\n", syscall_number);
     thread_exit ();

userprog/syscall_close.c

@@ -23,8 +23,6 @@ void syscall_close(struct intr_frame *f) {
 	}
 	// Close the file using file_close, defined in file.h
 	file_close(file);
-	if (disassociate_file_descriptor(file_descriptor) == false) { // Checking if file is empty or non-existent
-		f->eax = -1; // Returning a failure state
-		return;
-	}
+	// Remove the file_descriptor
+	disassociate_file_descriptor(file_descriptor);
 }
\ No newline at end of file

userprog/syscall_filesize.c

+/*
+ * Returns the size, in bytes, of the file open as fd.
+ *
+ * Authored by Alex Stratford
+ */
+
+#include "system_calls.h"
+#include "filesys/file.h"
+
+void syscall_filesize(struct intr_frame *f) {
+	// pop off first int argument from interrupt frame
+	int file_descriptor = *((int*)f->esp + 1);
+	struct file *file = get_associated_file_pointer(file_descriptor);
+	if (file == NULL) { // Checking if file is empty or non-existent
+		f->eax -1; // Returning failure state
+	}
+	// Using the file_length function in file.h to get the length and store it
+	int size = file_length(file); 
+	f->eax = size;
+}
\ No newline at end of file

userprog/syscall_open.c

@@ -14,7 +14,7 @@
 
 void syscall_open(struct intr_frame *f) {
 	// pop off first int argument from interrupt frame
-	char* file_name = (void*)(*(int*)f->esp + 1);
+	char* file_name = (void*)*((int*)f->esp + 1);
 	// Described in filesys.h, opens the file
 	struct file *file = filesys_open(file_name);
 	if (file == NULL) { // Checking if file is empty or non-existent

userprog/syscall_remove.c

+/*
+ * Deletes the file called file. Returns true if successful, false otherwise. 
+ * A file may be removed regardless of whether it is open or closed, and 
+ * Removing an open file does not close it. See Removing an Open File, for
+ * Details.
+ *
+ * Authored by Alex Stratford
+ */
+
+
+#include "system_calls.h"
+#include "threads/interrupt.h" // Dependency for intr_frame struct
+#include "filesys/file.h" // Dependency for and file struct
+#include "filesys/filesys.h" // Dependency for filesys_remove
+
+void syscall_remove(struct intr_frame *f) {
+	// pop off first int argument from interrupt frame
+	char* file_name = (void*)*((int*)f->esp + 1);
+	// Described in filesys.h, opens the file
+	if (filesys_remove(file_name) == false) { // Checking if file is empty or non-existent
+		f->eax = false; // Returning a failure state
+		return;
+	}
+	f->eax = true;
+}

userprog/system_calls.h

@@ -57,9 +57,17 @@ void syscall_write(struct intr_frame *f);
 void syscall_open(struct intr_frame *f);
 
 /*
- * NOTE: There are more system calls implemented by Pintos but we are not
- * implementing them because the assignment brief does not ask of it.
+ * Returns the size, in bytes, of the file open as fd.
  */
+void syscall_filesize(struct intr_frame *f);
+
+/*
+ * Deletes the file called file. Returns true if successful, false otherwise.
+ * A file may be removed regardless of whether it is open or closed, and
+ * Removing an open file does not close it. See Removing an Open File, for
+ * Details.
+ */
+void syscall_remove(struct intr_frame *f);
 
 /*
  * special additional stuff for handling file descriptors because they're annoying