Kernel/VFS - Better error reporting in open

[tpg/acess2.git] / KernelLand / Kernel / vfs / open.c

diff --git a/KernelLand/Kernel/vfs/open.c b/KernelLand/Kernel/vfs/open.c
index f0b5734..e5a206f 100644 (file)
--- a/KernelLand/Kernel/vfs/open.c
+++ b/KernelLand/Kernel/vfs/open.c
@@ -15,16 +15,29 @@
 #define MAX_PATH_SLASHES       256
 #define MAX_NESTED_LINKS       4
 #define MAX_PATH_LEN   255
+#define MAX_MARSHALLED_HANDLES 16      // Max outstanding
 
 // === IMPORTS ===
 extern tVFS_Mount      *gVFS_RootMount;
 extern tVFS_Node       *VFS_MemFile_Create(const char *Path);
 
+// === TYPES ===
+typedef struct sVFS_MarshaledHandle
+{
+       Uint32  Magic;
+       tTime   AllocTime;
+       tVFS_Handle     Handle;
+} tVFS_MarshalledHandle;
+
 // === PROTOTYPES ===
 void   _ReferenceMount(tVFS_Mount *Mount, const char *DebugTag);
 void   _DereferenceMount(tVFS_Mount *Mount, const char *DebugTag);
  int   VFS_int_CreateHandle(tVFS_Node *Node, tVFS_Mount *Mount, int Mode);
 
+// === GLOBALS ===
+tMutex glVFS_MarshalledHandles;
+tVFS_MarshalledHandle  gaVFS_MarshalledHandles[MAX_MARSHALLED_HANDLES];
+
 // === CODE ===
 void _ReferenceMount(tVFS_Mount *Mount, const char *DebugTag)
 {
@@ -49,9 +62,9 @@ char *VFS_GetAbsPath(const char *Path)
        char    *tmpStr;
        int             iPos = 0;
        int             iPos2 = 0;
-       const char      *chroot = *Threads_GetChroot();
+       const char      *chroot = *Threads_GetChroot(NULL);
         int    chrootLen;
-       const char      *cwd = *Threads_GetCWD();
+       const char      *cwd = *Threads_GetCWD(NULL);
         int    cwdLen;
        
        ENTER("sPath", Path);
@@ -343,7 +356,7 @@ restart_parse:
                        }
                        
                        if(iNestedLinks > MAX_NESTED_LINKS) {
-                               Log_Notice("VFS", "VFS_ParsePath - Nested link limit exceeded");
+                               Log_Notice("VFS", "VFS_ParsePath - Nested link limit exceeded on '%.*s'", ofs, Path);
                                errno = ENOENT;
                                goto _error;
                        }
@@ -378,7 +391,8 @@ restart_parse:
                // Handle Non-Directories
                if( !(curNode->Flags & VFS_FFLAG_DIRECTORY) )
                {
-                       Log_Warning("VFS", "VFS_ParsePath - Path segment is not a directory");
+                       Log_Warning("VFS", "VFS_ParsePath - Path segment '%.*s' is not a directory (curNode{%p}->Flags = 0x%x)",
+                               ofs+nextSlash, Path, curNode, curNode->Flags);
                        errno = ENOTDIR;
                        goto _error;
                }
@@ -407,7 +421,7 @@ restart_parse:
 
        // Check final finddir call     
        if( !curNode->Type || !curNode->Type->FindDir ) {
-               Log_Warning("VFS", "VFS_ParsePath - FindDir doesn't exist for element of '%s'", Path);
+               Log_Warning("VFS", "VFS_ParsePath - FindDir doesn't exist for leaf of '%s' (dir '%.*s')", Path, ofs, Path);
                errno = ENOENT;
                goto _error;
        }
@@ -733,6 +747,7 @@ int VFS_Reopen(int FD, const char *Path, int Flags)
 
        int newf = VFS_Open(Path, Flags);
        if( newf == -1 ) {
+               // errno = set by VFS_Open
                return -1;
        }
        
@@ -759,11 +774,13 @@ void VFS_Close(int FD)
        h = VFS_GetHandle(FD);
        if(h == NULL) {
                Log_Warning("VFS", "Invalid file handle passed to VFS_Close, 0x%x", FD);
+               errno = EINVAL;
                return;
        }
 
        if( h->Node == NULL ) {
                Log_Warning("VFS", "Non-open handle passed to VFS_Close, 0x%x", FD);
+               errno = EINVAL;
                return ;
        }       
 
@@ -771,6 +788,7 @@ void VFS_Close(int FD)
        if(h->Node->Close && !MM_GetPhysAddr(h->Node->Close)) {
                Log_Warning("VFS", "Node %p's ->Close method is invalid (%p)",
                        h->Node, h->Node->Close);
+               errno = EINTERNAL;
                return ;
        }
        #endif
@@ -858,7 +876,7 @@ int VFS_ChDir(const char *Dest)
        VFS_Close(fd);
        
        {
-               char    **cwdptr = Threads_GetCWD();
+               char    **cwdptr = Threads_GetCWD(NULL);
                // Free old working directory
                if( *cwdptr )   free( *cwdptr );
                // Set new
@@ -910,7 +928,7 @@ int VFS_ChRoot(const char *New)
 
        // Update       
        {
-               char    **chroot_ptr = Threads_GetChroot();
+               char    **chroot_ptr = Threads_GetChroot(NULL);
                if( *chroot_ptr )       free( *chroot_ptr );
                *chroot_ptr = buf;
        }
@@ -920,6 +938,96 @@ int VFS_ChRoot(const char *New)
        return 1;
 }
 
+/*
+ * Marshal a handle so that it can be transferred between processes
+ */
+Uint64 VFS_MarshalHandle(int FD)
+{
+       tVFS_Handle     *h = VFS_GetHandle(FD);
+       if(!h || !h->Node) {
+               errno = EBADF;
+               return -1;
+       }
+       
+       // Allocate marshal location
+        int    ret = -1;
+       Mutex_Acquire(&glVFS_MarshalledHandles);
+       for( int i = 0; i < MAX_MARSHALLED_HANDLES; i ++ )
+       {
+               tVFS_MarshalledHandle*  mh = &gaVFS_MarshalledHandles[i];
+               if( mh->Handle.Node == NULL ) {
+                       mh->Handle.Node = h->Node;
+                       mh->AllocTime = now();
+                       ret = i;
+               }
+               if( now() - mh->AllocTime > 2000 ) {
+                       Log_Notice("VFS", "TODO: Expire marshalled handle");
+               }
+       }
+       Mutex_Release(&glVFS_MarshalledHandles);
+       if( ret < 0 ) {
+               // TODO: Need to clean up lost handles to avoid DOS
+               Log_Warning("VFS", "Out of marshaled handle slots");
+               errno = EAGAIN;
+               return -1;
+       }
+       
+       // Populate
+       tVFS_MarshalledHandle*  mh = &gaVFS_MarshalledHandles[ret];
+       mh->Handle = *h;
+       _ReferenceMount(h->Mount, "MarshalHandle");
+       _ReferenceNode(h->Node);
+       mh->Magic = rand();
+       
+       return (Uint64)mh->Magic << 32 | ret;
+}
+
+/*
+ * Un-marshal a handle into the current process
+ * NOTE: Does not support unmarshalling into kernel handle list
+ */
+int VFS_UnmarshalHandle(Uint64 Handle)
+{
+       Uint32  magic = Handle >> 32;
+        int    id = Handle & 0xFFFFFFFF;
+       
+       // Range check
+       if( id >= MAX_MARSHALLED_HANDLES ) {
+               LOG("ID too high (%i > %i)", id, MAX_MARSHALLED_HANDLES);
+               errno = EINVAL;
+               return -1;
+       }
+       
+       
+       // Check validity
+       tVFS_MarshalledHandle   *mh = &gaVFS_MarshalledHandles[id];
+       if( mh->Handle.Node == NULL ) {
+               LOG("Target node is NULL");
+               errno = EINVAL;
+               return -1;
+       }
+       if( mh->Magic != magic ) {
+               LOG("Magic mismatch (0x%08x != 0x%08x)", magic, mh->Magic);
+               errno = EACCES;
+               return -1;
+       }
+       
+       Mutex_Acquire(&glVFS_MarshalledHandles);
+       // - Create destination handle
+        int    ret = VFS_AllocHandle(true, mh->Handle.Node, mh->Handle.Mode);
+       // - Clear allocation
+       mh->Handle.Node = NULL;
+       Mutex_Release(&glVFS_MarshalledHandles);
+       if( ret == -1 ) {
+               errno = ENFILE;
+               return -1;
+       }
+       
+       // No need to reference node/mount, new handle takes marshalled reference
+       
+       return ret;
+}
+
 // === EXPORTS ===
 EXPORT(VFS_Open);
 EXPORT(VFS_Close);