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Merging upstream version 1.23.

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Signed-off-by: Daniel Baumann <daniel@debian.org>
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doc/lziprecover.info
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@ -1,7 +1,7 @@
This is lziprecover.info, produced by makeinfo version 4.13+ from
lziprecover.texi.
INFO-DIR-SECTION Data Compression
INFO-DIR-SECTION Compression
START-INFO-DIR-ENTRY
* Lziprecover: (lziprecover). Data recovery tool for the lzip format
END-INFO-DIR-ENTRY
@ -12,7 +12,7 @@ File: lziprecover.info, Node: Top, Next: Introduction, Up: (dir)
Lziprecover Manual
******************
This manual is for Lziprecover (version 1.22, 2 January 2021).
This manual is for Lziprecover (version 1.23, 21 January 2022).
* Menu:
@ -32,7 +32,7 @@ This manual is for Lziprecover (version 1.22, 2 January 2021).
* Concept index:: Index of concepts
Copyright (C) 2009-2021 Antonio Diaz Diaz.
Copyright (C) 2009-2022 Antonio Diaz Diaz.
This manual is free documentation: you have unlimited permission to copy,
distribute, and modify it.
@ -45,10 +45,10 @@ File: lziprecover.info, Node: Introduction, Next: Invoking lziprecover, Prev:
Lziprecover is a data recovery tool and decompressor for files in the lzip
compressed data format (.lz). Lziprecover is able to repair slightly damaged
files, produce a correct file by merging the good parts of two or more
damaged copies, reproduce a missing (zeroed) sector using a reference file,
extract data from damaged files, decompress files, and test integrity of
files.
files (up to one single-byte error per member), produce a correct file by
merging the good parts of two or more damaged copies, reproduce a missing
(zeroed) sector using a reference file, extract data from damaged files,
decompress files, and test integrity of files.
Lziprecover can remove the damaged members from multimember files, for
example multimember tar.lz archives.
@ -94,7 +94,7 @@ provides recovery capabilities like those of lziprecover, which is able to
find and combine the good parts of several damaged copies.
Lziprecover is able to recover or decompress files produced by any of the
compressors in the lzip family; lzip, plzip, minilzip/lzlib, clzip, and
compressors in the lzip family: lzip, plzip, minilzip/lzlib, clzip, and
pdlzip.
If the cause of file corruption is a damaged medium, the combination
@ -105,7 +105,7 @@ ddrescue-example2::, for examples.
If a file is too damaged for lziprecover to repair it, all the
recoverable data in all members of the file can be extracted with the
following command (the resulting file may contain errors and some garbage
data may be produced at the end of each member):
data may be produced at the end of each damaged member):
lziprecover -cd -i file.lz > file
@ -161,7 +161,7 @@ lziprecover decompresses from standard input to standard output.
dictionary size of the resulting file (and therefore the amount of
memory required to decompress it). Only streamed files with default
LZMA properties can be converted; non-streamed lzma-alone files lack
the end of stream marker required in lzip files.
the "End Of Stream" marker required in lzip files.
The name of the converted lzip file is derived from that of the
original lzma-alone file as follows:
@ -176,15 +176,18 @@ lziprecover decompresses from standard input to standard output.
unchanged. This option (or '-o') is needed when reading from a named
pipe (fifo) or from a device. Use it also to recover as much of the
decompressed data as possible when decompressing a corrupt file. '-c'
overrides '-o', but '-c' has no effect when merging, removing members,
overrides '-o'. '-c' has no effect when merging, removing members,
repairing, reproducing, splitting, testing or listing.
'-d'
'--decompress'
Decompress the files specified. If a file does not exist or can't be
opened, lziprecover continues decompressing the rest of the files. If
a file fails to decompress, or is a terminal, lziprecover exits
immediately without decompressing the rest of the files.
Decompress the files specified. If a file does not exist, can't be
opened, or the destination file already exists and '--force' has not
been specified, lziprecover continues decompressing the rest of the
files and exits with error status 1. If a file fails to decompress, or
is a terminal, lziprecover exits immediately with error status 2
without decompressing the rest of the files. A terminal is considered
an uncompressed file, and therefore invalid.
'-D RANGE'
'--range-decompress=RANGE'
@ -243,12 +246,12 @@ lziprecover decompresses from standard input to standard output.
'-cd -i' method resyncs to the next member header after each error,
and is immune to some format errors that make '-D0 -i' fail. The range
decompressed may be smaller than the range requested, because of the
errors.
errors. The exit status is set to 0 unless other errors are found (I/O
errors, for example).
Make '--list', '--dump', '--remove', and '--strip' ignore format
errors. The sizes of the members with errors (specially the last) may
be wrong. The exit status is set to 0 unless other errors are found
(I/O errors, for example).
be wrong.
'-k'
'--keep'
@ -267,10 +270,12 @@ lziprecover decompresses from standard input to standard output.
between members are shown. The member numbers shown coincide with the
file numbers produced by '--split'.
'-lq' can be used to verify quickly (without decompressing) the
structural integrity of the files specified. (Use '--test' to verify
the data integrity). '-alq' additionally verifies that none of the
files specified contain trailing data.
If any file is damaged, does not exist, can't be opened, or is not
regular, the final exit status will be > 0. '-lq' can be used to verify
quickly (without decompressing) the structural integrity of the files
specified. (Use '--test' to verify the data integrity). '-alq'
additionally verifies that none of the files specified contain
trailing data.
'-m'
'--merge'
@ -361,7 +366,7 @@ lziprecover decompresses from standard input to standard output.
If a file does not exist, can't be opened, or is not regular,
lziprecover continues processing the rest of the files. If the dump
fails in one file, lziprecover exits immediately without processing the
rest of the files.
rest of the files. Only '--dump=tdata' can write to a terminal.
The argument to '--dump' is a colon-separated list of the following
element specifiers; a member list (1,3-6), a reverse member list
@ -451,29 +456,39 @@ lziprecover decompresses from standard input to standard output.
byte values. Print cumulative data for all files followed by the name
of the first file with the longest sequence.
'-U'
'--unzcrash'
Test 1-bit errors in the LZMA stream of the input FILE like the
command 'unzcrash -b1 -p7 -s-20 'lzip -t' FILE' but in memory, and
therefore much faster. *Note Unzcrash::. This option tests all the
members independently in a multimember file, skipping headers and
trailers. If a decompression succeeds, the decompressed output is
compared with the original decompressed output of FILE using MD5
digests. The compressed FILE must not contain errors and must
decompress correctly for the comparisons to work.
'-U 1|BSIZE'
'--unzcrash=1|BSIZE'
With argument '1', test 1-bit errors in the LZMA stream of the
compressed input FILE like the command
'unzcrash -b1 -p7 -s-20 'lzip -t' FILE' but in memory, and therefore
much faster. *Note Unzcrash::. This option tests all the members
independently in a multimember file, skipping headers and trailers. If
a decompression succeeds, the decompressed output is compared with the
decompressed output of the original FILE using MD5 digests. FILE must
not contain errors and must decompress correctly for the comparisons to
work.
With argument 'B', test zeroed sectors (blocks of bytes) in the LZMA
stream of the compressed input FILE like the command
'unzcrash --block=SIZE -d1 -p7 -s-(SIZE+20) 'lzip -t' FILE' but in
memory, and therefore much faster. Testing and comparisons work just
like with the argument '1' explained above.
By default '--unzcrash' only prints the interesting cases; CRC
mismatches, size mismatches, unsupported marker codes, unexpected EOFs,
apparently successful decompressions, and decoder errors detected
50_000 or more bytes beyond the byte being tested. At verbosity level
1 (-v) it also prints decoder errors detected 10_000 or more bytes
beyond the byte being tested. At verbosity level 2 (-vv) it prints all
cases.
50_000 or more bytes beyond the byte (or the start of the block) being
tested. At verbosity level 1 (-v) it also prints decoder errors
detected 10_000 or more bytes beyond the byte being tested. At
verbosity level 2 (-vv) it prints all cases for 1-bit errors or the
decoder errors detected beyond the end of the block for zeroed blocks.
'-W POSITION,VALUE'
'--debug-decompress=POSITION,VALUE'
Load the compressed FILE into memory, set the byte at POSITION to
VALUE, and decompress the modified compressed data to standard output.
If the damaged member is decompressed fully (just fails with a CRC
mismatch), the members following it are also decompressed.
'-X[POSITION,VALUE]'
'--show-packets[=POSITION,VALUE]'
@ -517,7 +532,7 @@ Y yottabyte (10^24) | Yi yobibyte (2^80)
Exit status: 0 for a normal exit, 1 for environmental problems (file not
found, invalid flags, I/O errors, etc), 2 to indicate a corrupt or invalid
input file, 3 for an internal consistency error (eg, bug) which caused
input file, 3 for an internal consistency error (e.g., bug) which caused
lziprecover to panic.

@ -875,7 +890,7 @@ gmp-6.1.1.tar gmp-6.1.2.tar.lz 175 / 473 = 37%
gmp-6.1.2.tar gmp-6.1.1.tar.lz 181 / 472 = 38.35%
Note that the "performance of reproduce" is a probability, not a partial
recovery. The data is either fully recovered (with the probability X shown
recovery. The data is either recovered fully (with the probability X shown
in the last column of the tables above) or not recovered at all (with
probability 1 - X).
@ -1065,9 +1080,11 @@ when there is no longer anything to take away.
represents a variable number of bytes.
A lzip file consists of a series of "members" (compressed data sets).
The members simply appear one after another in the file, with no additional
information before, between, or after them.
A lzip file consists of a series of independent "members" (compressed
data sets). The members simply appear one after another in the file, with no
additional information before, between, or after them. Each member can
encode in compressed form up to 16 EiB - 1 byte of uncompressed data. The
size of a multimember file is unlimited.
Each member has the following structure:
@ -1095,21 +1112,22 @@ information before, between, or after them.
Valid values for dictionary size range from 4 KiB to 512 MiB.
'LZMA stream'
The LZMA stream, finished by an end of stream marker. Uses default
The LZMA stream, finished by an "End Of Stream" marker. Uses default
values for encoder properties. *Note Stream format: (lzip)Stream
format, for a complete description.
'CRC32 (4 bytes)'
Cyclic Redundancy Check (CRC) of the uncompressed original data.
Cyclic Redundancy Check (CRC) of the original uncompressed data.
'Data size (8 bytes)'
Size of the uncompressed original data.
Size of the original uncompressed data.
'Member size (8 bytes)'
Total size of the member, including header and trailer. This field acts
as a distributed index, allows the verification of stream integrity,
and facilitates safe recovery of undamaged members from multimember
files.
and facilitates the safe recovery of undamaged members from
multimember files. Member size should be limited to 2 PiB to prevent
the data size field from overflowing.

@ -1167,7 +1185,7 @@ Example 1: Add a comment or description to a compressed file.
# This command prints the comment to standard output
lziprecover --dump=tdata file.lz
# This command outputs file.lz without the comment
lziprecover --strip=tdata file.lz
lziprecover --strip=tdata file.lz > stripped_file.lz
# This command removes the comment from file.lz
lziprecover --remove=tdata file.lz
@ -1209,7 +1227,7 @@ Example 4: The right way of concatenating the decompressed output of two or
more compressed files. *Note Trailing data::.
Don't do this
cat file1.lz file2.lz file3.lz | lziprecover -d
cat file1.lz file2.lz file3.lz | lziprecover -d -
Do this instead
lziprecover -cd file1.lz file2.lz file3.lz
You may also concatenate the compressed files like this
@ -1292,7 +1310,10 @@ latter case, please, report any false negative as a bug.
In order to compare the outputs, unzcrash needs a 'zcmp' program able to
understand the format being tested. For example the 'zcmp' provided by
zutils. Use '--zcmp=false' to disable comparisons. *Note Zcmp: (zutils)Zcmp.
zutils. If the 'zcmp' program used does not understand the format being
tested, all the comparisons will fail because the compressed files will be
compared without being decompressed first. Use '--zcmp=false' to disable
comparisons. *Note Zcmp: (zutils)Zcmp.
The format for running unzcrash is:
@ -1393,7 +1414,7 @@ tested must decompress it correctly for the comparisons to work.
Exit status: 0 for a normal exit, 1 for environmental problems (file not
found, invalid flags, I/O errors, etc), 2 to indicate a corrupt or invalid
input file, 3 for an internal consistency error (eg, bug) which caused
input file, 3 for an internal consistency error (e.g., bug) which caused
unzcrash to panic.

@ -1443,32 +1464,32 @@ Concept index

Tag Table:
Node: Top231
Node: Introduction1410
Node: Invoking lziprecover5353
Ref: --trailing-error6220
Ref: range-format8391
Ref: --reproduce8726
Ref: --repair12904
Node: Data safety24532
Node: Merging with a backup26520
Node: Reproducing a mailbox27784
Node: Repairing one byte30285
Node: Merging files32350
Ref: performance-of-merge33520
Ref: ddrescue-example35129
Node: Reproducing one sector36416
Ref: performance-of-reproduce40299
Ref: ddrescue-example242974
Node: Tarlz45394
Node: File names49058
Node: File format49515
Node: Trailing data51964
Node: Examples55186
Ref: concat-example55762
Node: Unzcrash57152
Node: Problems63240
Node: Concept index63792
Node: Top226
Node: Introduction1406
Node: Invoking lziprecover5398
Ref: --trailing-error6265
Ref: range-format8644
Ref: --reproduce8979
Ref: --repair13278
Node: Data safety25584
Node: Merging with a backup27572
Node: Reproducing a mailbox28836
Node: Repairing one byte31337
Node: Merging files33402
Ref: performance-of-merge34572
Ref: ddrescue-example36181
Node: Reproducing one sector37468
Ref: performance-of-reproduce41351
Ref: ddrescue-example244026
Node: Tarlz46446
Node: File names50110
Node: File format50567
Node: Trailing data53258
Node: Examples56499
Ref: concat-example57075
Node: Unzcrash58467
Node: Problems64739
Node: Concept index65291

End Tag Table