diff options
Diffstat (limited to 'gnu/build/file-systems.scm')
| -rw-r--r-- | gnu/build/file-systems.scm | 24 |
1 files changed, 24 insertions, 0 deletions
diff --git a/gnu/build/file-systems.scm b/gnu/build/file-systems.scm index b06a4cc25c..1d3b33e7bd 100644 --- a/gnu/build/file-systems.scm +++ b/gnu/build/file-systems.scm @@ -52,6 +52,8 @@ read-partition-uuid read-luks-partition-uuid + cleanly-unmounted-ext2? + bind-mount system*/tty @@ -193,6 +195,23 @@ NUL terminator, return the size of the bytevector." if DEVICE does not contain an ext2 file system." (read-superblock device 1024 264 ext2-superblock?)) +(define (ext2-superblock-cleanly-unmounted? sblock) + "Return true if SBLOCK denotes a file system that was cleanly unmounted, +false otherwise." + (define EXT2_VALID_FS 1) ;cleanly unmounted + (define EXT2_ERROR_FS 2) ;errors detected + + (define EXT3_FEATURE_INCOMPAT_RECOVER #x0004) ;journal needs recovery + + (let ((state (bytevector-u16-ref sblock 58 %ext2-endianness))) + (cond ((= state EXT2_VALID_FS) + (let ((incompatible-features + (bytevector-u32-ref sblock 96 %ext2-endianness))) + (zero? (logand incompatible-features + EXT3_FEATURE_INCOMPAT_RECOVER)))) + ((= state EXT2_ERROR_FS) #f) + (else (error "invalid ext2 superblock state" state))))) + (define (ext2-superblock-uuid sblock) "Return the UUID of ext2 superblock SBLOCK as a 16-byte bytevector." (sub-bytevector sblock 104 16)) @@ -220,6 +239,11 @@ errors. Otherwise, fix only those considered safe to repair automatically." (2 'reboot-required) (_ 'fatal-error))) +(define (cleanly-unmounted-ext2? device) ;convenience procedure + "Return true if DEVICE is an ext2 file system and if it was cleanly +unmounted." + (ext2-superblock-cleanly-unmounted? (read-ext2-superblock device))) + ;;; ;;; Linux swap. |