.\" zip_source_zip_file.mdoc -- create data source from zip file
.\" Copyright (C) 2004-2021 Dieter Baron and Thomas Klausner
.\"
.\" This file is part of libzip, a library to manipulate ZIP archives.
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.Dd March 10, 2023
.Dt ZIP_SOURCE_ZIP_FILE 3
.Os
.Sh NAME
.Nm zip_source_zip_file ,
.Nm zip_source_zip_file_create
.Nd create data source from zip file
.Sh LIBRARY
libzip (-lzip)
.Sh SYNOPSIS
.In zip.h
.Ft zip_source_t *
.Fn zip_source_zip_file "zip_t *archive" "zip_t *srcarchive" "zip_uint64_t srcidx" "zip_flags_t flags" "zip_uint64_t start" "zip_int64_t length" "const char *password"
.Ft zip_source_t *
.Fn zip_source_zip_file_create "zip_t *srcarchive" "zip_uint64_t srcidx" "zip_flags_t flags" "zip_uint64_t start" "zip_int64_t length" "const char *password" "zip_error_t *error"
.Sh DESCRIPTION
The functions
.Fn zip_source_zip_file
and
.Fn zip_source_zip_file_create
create a zip source from a file in a zip archive.
The
.Ar srcarchive
argument is the (open) zip archive containing the source zip file
at index
.Ar srcidx .
.Ar length
bytes from offset
.Ar start
will be used in the zip_source.
If
.Ar length
is \-1, the rest of the file, starting from
.Ar start ,
is used.
.Pp
If you intend to copy a file from one archive to another, using the flag
.Dv ZIP_FL_COMPRESSED
is more efficient, as it avoids recompressing the file data.
.Pp
Supported flags are:
.Bl -tag -width 20n
.It Dv ZIP_FL_COMPRESSED
Get the compressed data.
This is only supported if the complete file data is requested
.Ar ( start
== 0 and
.Ar length
== \-1).
This is not supported for changed data.
Default is uncompressed.
.It Dv ZIP_FL_ENCRYPTED
Get the encrypted data.
(This flag implies
.Dv ZIP_FL_COMPRESSED . )
This is only supported if the complete file data is requested
.Ar ( start
== 0 and
.Ar length
== \-1).
Default is decrypted.
.It Dv ZIP_FL_UNCHANGED
Try to get the original data without any changes that may have been
made to
.Ar srcarchive
after opening it.
.El
.Sh RETURN VALUES
Upon successful completion, the created source is returned.
Otherwise,
.Dv NULL
is returned and the error code in
.Ar archive
or
.Ar error
is set to indicate the error.
.Sh ERRORS
.Fn zip_source_zip_file
and
.Fn zip_source_zip_file_create
fail if:
.Bl -tag -width Er
.It Bq Er ZIP_ER_CHANGED
Unchanged data was requested, but it is not available.
.It Bq Er ZIP_ER_INVAL
.Ar srcarchive ,
.Ar srcidx ,
.Ar start ,
or
.Ar length
are invalid.
.It Bq Er ZIP_ER_MEMORY
Required memory could not be allocated.
.El
Additionally, it can return all error codes from
.Fn zip_stat_index
and
.Fn zip_fopen_index .
.Sh SEE ALSO
.Xr libzip 3 ,
.Xr zip_file_add 3 ,
.Xr zip_file_replace 3 ,
.Xr zip_source 3
.Sh HISTORY
.Fn zip_source_zip_file
and
.Fn zip_source_zip_file_create
were added in libzip 1.10.0.
.Sh AUTHORS
.An -nosplit
.An Dieter Baron Aq Mt dillo@nih.at
and
.An Thomas Klausner Aq Mt tk@giga.or.at