[edk2-devel] [edk2 PATCH 29/48] OvmfPkg/VirtioFsDxe: add helper for formatting UEFI basenames
Laszlo Ersek
lersek at redhat.com
Wed Dec 16 21:11:06 UTC 2020
The EFI_FILE_INFO structure, which is output by
EFI_FILE_PROTOCOL.GetInfo(), ends with a flexible CHAR16 array called
"FileName". Add the VirtioFsGetBasename() function, for determining the
required array size, and for filling the array as well.
Cc: Ard Biesheuvel <ard.biesheuvel at arm.com>
Cc: Jordan Justen <jordan.l.justen at intel.com>
Cc: Philippe Mathieu-Daudé <philmd at redhat.com>
Ref: https://bugzilla.tianocore.org/show_bug.cgi?id=3097
Signed-off-by: Laszlo Ersek <lersek at redhat.com>
---
OvmfPkg/VirtioFsDxe/VirtioFsDxe.h | 7 +++
OvmfPkg/VirtioFsDxe/Helpers.c | 61 ++++++++++++++++++++
2 files changed, 68 insertions(+)
diff --git a/OvmfPkg/VirtioFsDxe/VirtioFsDxe.h b/OvmfPkg/VirtioFsDxe/VirtioFsDxe.h
index 029c568b39c7..d1b746c0d8cf 100644
--- a/OvmfPkg/VirtioFsDxe/VirtioFsDxe.h
+++ b/OvmfPkg/VirtioFsDxe/VirtioFsDxe.h
@@ -229,16 +229,23 @@ VirtioFsAppendPath (
EFI_STATUS
VirtioFsLookupMostSpecificParentDir (
IN OUT VIRTIO_FS *VirtioFs,
IN OUT CHAR8 *Path,
OUT UINT64 *DirNodeId,
OUT CHAR8 **LastComponent
);
+EFI_STATUS
+VirtioFsGetBasename (
+ IN CHAR8 *Path,
+ OUT CHAR16 *Basename OPTIONAL,
+ IN OUT UINTN *BasenameSize
+ );
+
EFI_STATUS
VirtioFsFuseAttrToEfiFileInfo (
IN VIRTIO_FS_FUSE_ATTRIBUTES_RESPONSE *FuseAttr,
OUT EFI_FILE_INFO *FileInfo
);
//
// Wrapper functions for FUSE commands (primitives).
diff --git a/OvmfPkg/VirtioFsDxe/Helpers.c b/OvmfPkg/VirtioFsDxe/Helpers.c
index 6adc0341dee6..77f718e91233 100644
--- a/OvmfPkg/VirtioFsDxe/Helpers.c
+++ b/OvmfPkg/VirtioFsDxe/Helpers.c
@@ -1717,16 +1717,77 @@ VirtioFsLookupMostSpecificParentDir (
*LastComponent = Slash + 1;
return EFI_SUCCESS;
ForgetNextDirNodeId:
VirtioFsFuseForget (VirtioFs, NextDirNodeId);
return Status;
}
+/**
+ Format the last component of a canonical pathname into a caller-provided
+ CHAR16 array.
+
+ @param[in] Path The canonical pathname (as defined in the
+ description of VirtioFsAppendPath()) to format
+ the last component of.
+
+ @param[out] Basename If BasenameSize is zero on input, Basename may
+ be NULL. Otherwise, Basename is allocated by the
+ caller. On successful return, Basename contains
+ the last component of Path, formatted as a
+ NUL-terminated CHAR16 string. When Path is "/"
+ on input, Basename is L"" on output.
+
+ @param[in,out] BasenameSize On input, the number of bytes the caller
+ provides in Basename. On output, regardless of
+ return value, the number of bytes required for
+ formatting Basename, including the terminating
+ L'\0'.
+
+ @retval EFI_SUCCESS Basename has been filled in.
+
+ @retval EFI_BUFFER_TOO_SMALL BasenameSize was too small on input; Basename
+ has not been modified.
+**/
+EFI_STATUS
+VirtioFsGetBasename (
+ IN CHAR8 *Path,
+ OUT CHAR16 *Basename OPTIONAL,
+ IN OUT UINTN *BasenameSize
+ )
+{
+ UINTN AllocSize;
+ UINTN LastComponent;
+ UINTN Idx;
+ UINTN PathSize;
+
+ AllocSize = *BasenameSize;
+
+ LastComponent = MAX_UINTN;
+ for (Idx = 0; Path[Idx] != '\0'; Idx++) {
+ if (Path[Idx] == '/') {
+ LastComponent = Idx;
+ }
+ }
+ PathSize = Idx + 1;
+ ASSERT (LastComponent < MAX_UINTN);
+ LastComponent++;
+ *BasenameSize = (PathSize - LastComponent) * sizeof Basename[0];
+
+ if (*BasenameSize > AllocSize) {
+ return EFI_BUFFER_TOO_SMALL;
+ }
+
+ for (Idx = LastComponent; Idx < PathSize; Idx++) {
+ Basename[Idx - LastComponent] = Path[Idx];
+ }
+ return EFI_SUCCESS;
+}
+
/**
Convert select fields of a VIRTIO_FS_FUSE_ATTRIBUTES_RESPONSE object to
corresponding fields in EFI_FILE_INFO.
@param[in] FuseAttr The VIRTIO_FS_FUSE_ATTRIBUTES_RESPONSE object to
convert the relevant fields from.
@param[out] FileInfo The EFI_FILE_INFO structure to modify. Importantly, the
--
2.19.1.3.g30247aa5d201
-=-=-=-=-=-=-=-=-=-=-=-
Groups.io Links: You receive all messages sent to this group.
View/Reply Online (#69043): https://edk2.groups.io/g/devel/message/69043
Mute This Topic: https://groups.io/mt/79023796/1813853
Group Owner: devel+owner at edk2.groups.io
Unsubscribe: https://edk2.groups.io/g/devel/unsub [edk2-devel-archive at redhat.com]
-=-=-=-=-=-=-=-=-=-=-=-
More information about the edk2-devel-archive
mailing list