PDF-hul: false error message PDF-hul 71 due to incorrect end of line in cross-reference table

[awaldlza]

All specifications (from 1.3 to 2.0) state in some form, that in the cross-reference table the keywords "n" and "f" shall be followed by a two character end-of-line sequence, consisting of SP CR, SP LF or CR LF.
Exact wording in 2.0:
"Following the generation number shall be a single SPACE, the keyword n, and a 2-character end-of-line sequence consisting of one of the following: SP CR, SP LF, or CR LF. Thus, the overall length of the entry shall always be exactly 20 bytes." (specification for 2.0, 7.5.4).

Wording in 1.3: "Following the generation number is a single space, the keyword n, and then a 2-character end-of-line sequence. If the file’s end-of-line marker is a single character (either a carriage return or a line feed), it is preceded by a single space; if the marker is 2 characters (both a carriage return and a line feed), it is not preceded by a space. Thus the overall length of the entry is always exactly 20 bytes. (spec for 1.3, 3.4.3.

If a file does not follow that specification jhove (v. 1.34.0) seems to throw the error: https://github.com/openpreserve/jhove/wiki/PDF-hul-Messages#pdf-hul-71

Attached you find a sample file that throws this error.

false_pdf-hul-71_mod_0a.pdf

[carlwilson]

Thanks for reporting this @awaldlza. I thought I was having trouble understanding the issue, but I think I do now. To summarise, failure to follow the specification for the n/f keywords in the cross-ref table results in JHOVE reporting that no file trailer can be found. What should be reported is the cross-ref table error instead. I can't promise this will make the upcoming release, but I will use the sample you've supplied (thanks for that) to reproduce the issue and get back to you here with my thoughts.