Changeset 23 for trunk/kernel/syscalls/sys_lseek.c

Timestamp:

Jun 18, 2017, 10:06:41 PM (7 years ago)

Author:

alain

Message:

Introduce syscalls.

File:

• trunk/kernel/syscalls/sys_lseek.c (modified) (1 diff)

trunk/kernel/syscalls/sys_lseek.c

@@ -21 +21 @@
  */
 
-#include <types.h>
+#include <kernel_config.h>
+#include <hal_types.h>
+#include <hal_uspace.h>
+#include <errno.h>
 #include <vfs.h>
+#include <vmm.h>
 #include <thread.h>
-#include <sys-vfs.h>
-#include <task.h>
+#include <printk.h>
+#include <process.h>
 
-int sys_lseek (uint_t fd, off_t offset, int whence)
+////////////////////////////////
+int sys_lseek (uint32_t file_id,
+               uint32_t offset,
+               uint32_t whence )
 {
-        error_t err = 0;
-        size_t new_offset;
-        struct thread_s *this;
-        struct task_s *task;
-        struct vfs_file_s *file;
+        error_t    error;
+    xptr_t     file_xp;
+    uint32_t   new_offset;
 
-        file = NULL;
-        this = current_thread;
-        task = current_task;
+        thread_t  * this    = CURRENT_THREAD;
+        process_t * process = this->process;
+
+    // check file_id argument
+        if( file_id >= CONFIG_PROCESS_FILE_MAX_NR )
+        {
+        printk("\n[ERROR] in %s : illegal file descriptor index = %d\n",
+               __FUNCTION__ , file_id );
+                this->errno = EBADFD;
+                return -1;
+        }
+
+    // get extended pointer on remote file descriptor
+    file_xp = process_fd_get_xptr( process , file_id );
+
+    if( file_xp == XPTR_NULL )
+    {
+        printk("\n[ERROR] in %s : undefined file descriptor index = %d\n",
+               __FUNCTION__ , file_id );
+                this->errno = EBADFD;
+                return -1;
+    }
 
         /* FIXME: file may be closed in parallel 
          * of seek/read/write/mmap ..etc 
          * so file may be NULL or invalid */
-        if((fd >= CONFIG_TASK_FILE_MAX_NR) || (task_fd_lookup(task, fd, &file)))
+
+    // call relevant VFS function
+        error = vfs_lseek( file_xp , offset , whence , &new_offset );
+
+        if( error )
         {
-                this->info.errno = EBADFD;
-                return -1;
-        }
-
-        if((err = vfs_lseek(file, offset, whence, &new_offset)))
-        {
-                this->info.errno = (err < 0) ? -err : err;
+        printk("\n[ERROR] in %s : cannot seek file = %d\n",
+               __FUNCTION__ , file_id );
+                this->errno = error;
                 return -1;
         }