On Mon, Jul 03, 2017 at 05:36:52PM +0100, Nicholas Marriott wrote: > Hi > > On Thu, Jun 29, 2017 at 09:29:57PM +0200, Klemens Nanni wrote: > > While reading file(1)'s code in #openbsd-daily mulander noted that the > > 'name' and 'use' types were missing from magic(5). > > > > I'm not entirely sure yet whether this is complete, so here's what I > > did: > > > > magic(5) provided by devel/magic documents version 5.31 while base's > > magic(5) is at 4.24. Here are the types found in 5.31 but not ours as > > well as those of the missing ones that are actually implemented but > > undocumented as of now: > > > > $ grep -i "TYPE_($(grep -F 'It Dv' $(man -w magic) | > > cut -d' ' -f3 | sort | uniq -u | paste -sd\| - | > > tee /dev/stderr))" magic.h > > beid3|beqwdate|clear|indirect|leid3|leqwdate|name|qwdate|use > > MAGIC_TYPE_CLEAR, > > MAGIC_TYPE_NAME, > > MAGIC_TYPE_USE, > > > > What about the current version being 4.21? We're clearly ahead of this, > > it seems magic(5) wasn't updated when nicm@ reimplemented things. > > > > This patch documents the respective types. > > Did you copy this text from upstream or write it? > > Some comments inline. > > > Feedback/OK? > > > > Index: magic.5 > > =================================================================== > > RCS file: /cvs/src/usr.bin/file/magic.5,v > > retrieving revision 1.17 > > diff -u -p -r1.17 magic.5 > > --- magic.5 24 Apr 2016 07:02:07 -0000 1.17 > > +++ magic.5 29 Jun 2017 17:41:56 -0000 > > @@ -218,6 +218,31 @@ This is intended to be used with the tes > > .Em x > > (which is always true) and a message that is to be used if there are > > no other matches. > > +.It Dv clear > > +This test is always true and clears the match flag for that continuation > > +level. > > I would just say "that level" or "the test's level" not "that > continuation level" because there is no previous mention of > "continuation". > > > +It is intended to be used with the default test. > > +.It Dv name > > +Define a > > +.Dq named > > I don't think quotation marks are necessary here. > > > +magic instance that can be called from another > > +.Dv use > > +magic entry, like a subroutine call. > > +Named instance direct magic offsets are relative to the offset of the > > +previous matched entry, but indirect offsets are relative to the > > +beginning of the file as usual. > > +Named magic entries always match. > > +.It Dv use > > +Recursively call the named magic starting from the current offset. > > +If the name of the referenced begins with a > > "the referenced instance" would be better than "the referenced". Here's an updated diff incorporating your suggestions.
I didn't touch the manual's first sentence mentioning file(1)'s version since nicm@ reimplemented file(1) with revision 1.11 on 2015/04/24. He or someone else more knowledgable in this regard might want to bump it accordingly. Feedback? Comments? Index: magic.5 =================================================================== RCS file: /cvs/src/usr.bin/file/magic.5,v retrieving revision 1.17 diff -u -p -r1.17 magic.5 --- magic.5 24 Apr 2016 07:02:07 -0000 1.17 +++ magic.5 25 Jul 2017 18:56:40 -0000 @@ -30,7 +30,7 @@ .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF .\" SUCH DAMAGE. .\" -.Dd $Mdocdate: April 24 2016 $ +.Dd $Mdocdate: July 25 2017 $ .Dt MAGIC 5 .Os .\" install as magic.4 on USG, magic.5 on V7, Berkeley and Linux systems. @@ -218,6 +218,28 @@ This is intended to be used with the tes .Em x (which is always true) and a message that is to be used if there are no other matches. +.It Dv clear +This test is always true and clears the match flag for that level. +It is intended to be used with the default test. +.It Dv name +Define a named magic instance that can be called from another +.Dv use +magic entry, like a subroutine call. +Named instance direct magic offsets are relative to the offset of the +previous matched entry, but indirect offsets are relative to the +beginning of the file as usual. +Named magic entries always match. +.It Dv use +Recursively call the named magic starting from the current offset. +If the name of the referenced instance begins with a +.Dv ^ +then the endianness of the magic is switched; if the magic mentioned +.Dv leshort +for example, +it is treated as +.Dv beshort +and vice versa. +This is useful to avoid duplicating the rules for different endianness. .El .Pp Each top-level magic pattern (see below for an explanation of levels)
