Changeset 407 for trunk/kernel/syscalls/sys_stat.c

Timestamp:

Nov 7, 2017, 3:08:12 PM (7 years ago)

Author:

alain

Message:

First implementation of fork/exec.

File:

• trunk/kernel/syscalls/sys_stat.c (modified) (3 diffs)

trunk/kernel/syscalls/sys_stat.c

@@ -32 +32 @@
 #include <process.h>
 
-//////////////////////////////////////////
-int sys_stat( uint32_t            file_id,
-              struct vfs_stat_s * stat )
+/////////////////////////////////////
+int sys_stat( char        * pathname,
+              struct stat * u_stat )
 {
-    error_t           error;
-    paddr_t           paddr;
-    struct vfs_stat_s k_stat;
-    xptr_t            file_xp;
+    error_t       error;
+    paddr_t       paddr;
+    struct stat   k_stat;       // kernel space 
+    xptr_t        file_xp;
+    char          kbuf[CONFIG_VFS_MAX_PATH_LENGTH];
         
         thread_t  * this    = CURRENT_THREAD;
@@ -45 +46 @@
 
     // check stat structure in user space
-    error = vmm_v2p_translate( false , stat , &paddr );
+    error = vmm_v2p_translate( false , u_stat , &paddr );
 
         if( error )
@@ -55 +56 @@
         }       
 
-    // get extended pointer on remote file descriptor
-    file_xp = process_fd_get_xptr( process , file_id );
-
-    if( file_xp == XPTR_NULL )
+    // check pathname length
+    if( hal_strlen_from_uspace( pathname ) >= CONFIG_VFS_MAX_PATH_LENGTH )
     {
-        printk("\n[ERROR] in %s : undefined file descriptor for thread %x in process %x\n",
-               __FUNCTION__ , this->trdid , process->pid );
-        this->errno = EBADFD;
+        printk("\n[ERROR] in %s : pathname too long\n", __FUNCTION__ );
+        this->errno = ENFILE;
         return -1;
     }
 
-    // call the relevant VFS function
+    // copy pathname in kernel space
+    hal_strcpy_from_uspace( kbuf , pathname , CONFIG_VFS_MAX_PATH_LENGTH );
+
+    // get cluster and local pointer on reference process
+    xptr_t      ref_xp  = process->ref_xp;
+    process_t * ref_ptr = (process_t *)GET_PTR( ref_xp );
+    cxy_t       ref_cxy = GET_CXY( ref_xp );
+
+    // get extended pointer on cwd inode
+    xptr_t cwd_xp = hal_remote_lwd( XPTR( ref_cxy , &ref_ptr->vfs_cwd_xp ) );
+
+    // get the cwd lock in read mode from reference process
+    remote_rwlock_rd_lock( XPTR( ref_cxy , &ref_ptr->cwd_lock ) );
+
+    // get extended pointer on remote file descriptor
+    error = vfs_lookup( cwd_xp,
+                        pathname,
+                        0,
+                        &file_xp );
+
+    // release the cwd lock
+    remote_rwlock_rd_unlock( XPTR( ref_cxy , &ref_ptr->cwd_lock ) );
+
+    if( error )
+    {
+        printk("\n[ERROR] in %s : cannot found file <%s> for thread %x in process %x\n",
+               __FUNCTION__ , pathname , this->trdid , process->pid );
+        this->errno = error;
+        return -1;
+    }
+
+    // call VFS function to get stat info
     error = vfs_stat( file_xp,
                       &k_stat );
     if( error )
         {
-        printk("\n[ERROR] in %s : cannot access file %d for thread %x in process %x\n",
-               __FUNCTION__ , file_id , this->trdid , process->pid );
+        printk("\n[ERROR] in %s : cannot get stats for file %s\n",
+               __FUNCTION__ , pathname );
                 this->errno = error;
                 return -1;
         }
    
-    // copy stat to user space
-    hal_copy_to_uspace( stat , &k_stat , sizeof(struct vfs_stat_s) );
+    // copy k_stat to u_stat 
+    hal_copy_to_uspace( u_stat , &k_stat , sizeof(struct stat) );
 
     hal_fence();