Ticket #4128: improve handling of compressed content in mc.ext.

call 'file' with -z switch to enable getting the type of compressed files,
and use that capability extensively.

the /logs?/ hacks in ext.d/text.sh need to remain for the time being, as
file -z doesn't handle .lz4 files as encapsulated content.

Signed-off-by: Andrew Borodin <aborodin@vmail.ru>

misc/mc.ext.in

@@ -361,16 +361,6 @@ shell/.info
 shell/i/.3gp
 	Include=video
 
-# Manual page
-regex/(([^0-9]|^[^\.]*)\.([1-9][A-Za-z]*|[ln])|\.man)$
-	Open=@EXTHELPERSDIR@/text.sh open man %var{PAGER:more}
-	View=%view{ascii,nroff} @EXTHELPERSDIR@/text.sh view man %var{PAGER:more}
-
-# Perl pod page
-shell/.pod
-	Open=@EXTHELPERSDIR@/text.sh open pod %var{PAGER:more}
-	View=%view{ascii,nroff} @EXTHELPERSDIR@/text.sh view pod %var{PAGER:more}
-
 # Troff with me macros.
 # Exception - "read.me" is not a nroff file.
 shell/read.me
@@ -387,18 +377,28 @@ shell/.ms
 	View=%view{ascii,nroff} @EXTHELPERSDIR@/text.sh view nroff.ms %var{PAGER:more}
 
 # Manual page - compressed
-regex/([^0-9]|^[^\.]*)\.([1-9][A-Za-z]*|[ln])\.g?[Zz]$
+type/^(ASCII )?troff.*gzip compressed
 	Open=@EXTHELPERSDIR@/text.sh open man.gz %var{PAGER:more}
 	View=%view{ascii,nroff} @EXTHELPERSDIR@/text.sh view man.gz %var{PAGER:more}
 
-regex/([^0-9]|^[^\.]*)\.([1-9][A-Za-z]*|[ln])\.bz$
+type/^(ASCII )?troff.*bzip compressed
 	Open=@EXTHELPERSDIR@/text.sh open man.bz %var{PAGER:more}
 	View=%view{ascii,nroff} @EXTHELPERSDIR@/text.sh view man.bz %var{PAGER:more}
 
-regex/([^0-9]|^[^\.]*)\.([1-9][A-Za-z]*|[ln])\.bz2$
+type/^(ASCII )?troff.*bzip2 compressed
 	Open=@EXTHELPERSDIR@/text.sh open man.bz2 %var{PAGER:more}
 	View=%view{ascii,nroff} @EXTHELPERSDIR@/text.sh view man.bz2 %var{PAGER:more}
 
+# Manual page
+type/^(ASCII )?troff
+	Open=@EXTHELPERSDIR@/text.sh open man %var{PAGER:more}
+	View=%view{ascii,nroff} @EXTHELPERSDIR@/text.sh view man %var{PAGER:more}
+
+# Perl pod page
+shell/.pod
+	Open=@EXTHELPERSDIR@/text.sh open pod %var{PAGER:more}
+	View=%view{ascii,nroff} @EXTHELPERSDIR@/text.sh view pod %var{PAGER:more}
+
 regex/([^0-9]|^[^\.]*)\.([1-9][A-Za-z]*|[ln])\.lz$
 	Open=@EXTHELPERSDIR@/text.sh open man.lz %var{PAGER:more}
 	View=%view{ascii,nroff} @EXTHELPERSDIR@/text.sh view man.lz %var{PAGER:more}
@@ -761,38 +761,27 @@ shell/i/.zoo
 	View=%view{ascii} @EXTHELPERSDIR@/archive.sh view zoo
 
 # gzip
-type/^gzip
+type/\(gzip compressed
 	Open=@EXTHELPERSDIR@/archive.sh view gz %var{PAGER:more}
 	View=%view{ascii} @EXTHELPERSDIR@/archive.sh view gz
 
-regex/\.(gz|Z)$
-	View=%view{ascii} @EXTHELPERSDIR@/archive.sh view gz
-
 # bzip2
-type/^bzip2
+type/\(bzip2 compressed
 	Open=@EXTHELPERSDIR@/archive.sh view bzip2 %var{PAGER:more}
 	View=%view{ascii} @EXTHELPERSDIR@/archive.sh view bz2
 
-regex/\.bz2?$
-	View=%view{ascii} @EXTHELPERSDIR@/archive.sh view bz2
-
 # bzip
-type/^bzip
+type/\(bzip compressed
 	Open=@EXTHELPERSDIR@/archive.sh view bzip %var{PAGER:more}
 	View=%view{ascii} @EXTHELPERSDIR@/archive.sh view bzip
 
 # compress
-type/^compress
+type/\(compress'd
 	Open=@EXTHELPERSDIR@/archive.sh view gz %var{PAGER:more}
 	View=%view{ascii} @EXTHELPERSDIR@/archive.sh view gz
 
 # lz
-regex/\.lz$
+type/\(lzip compressed
-	Open=@EXTHELPERSDIR@/archive.sh view lz %var{PAGER:more}
-	View=%view{ascii} @EXTHELPERSDIR@/archive.sh view lz
-
-# lz
-type/^LZIP
 	Open=@EXTHELPERSDIR@/archive.sh view lz %var{PAGER:more}
 	View=%view{ascii} @EXTHELPERSDIR@/archive.sh view lz
 
@@ -802,17 +791,17 @@ regex/\.lz4$
 	View=%view{ascii} @EXTHELPERSDIR@/archive.sh view lz4
 
 # lzma
-regex/\.lzma$
+type/\(LZMA compressed
 	Open=@EXTHELPERSDIR@/archive.sh view lzma %var{PAGER:more}
 	View=%view{ascii} @EXTHELPERSDIR@/archive.sh view lzma
 
 # xz
-regex/\.xz$
+type/\(XZ compressed
 	Open=@EXTHELPERSDIR@/archive.sh view xz %var{PAGER:more}
 	View=%view{ascii} @EXTHELPERSDIR@/archive.sh view xz
 
 # zstd
-regex/\.zst$
+type/\(Zstandard compressed
 	Open=@EXTHELPERSDIR@/archive.sh view zst %var{PAGER:more}
 	View=%view{ascii} @EXTHELPERSDIR@/archive.sh view zst
 

src/filemanager/ext.c

@@ -71,9 +71,9 @@
 /*** file scope macro definitions ****************************************************************/
 
 #ifdef FILE_L
-#define FILE_CMD "file -L "
+#define FILE_CMD "file -L -z "
 #else
-#define FILE_CMD "file "
+#define FILE_CMD "file -z "
 #endif
 
 /*** file scope type declarations ****************************************************************/