[src/trunk]: src/usr.bin/gzip factor out filetype checking code

[mrg <mrg%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/712fb4cbe45a
branches:  trunk
changeset: 565130:712fb4cbe45a
user:      mrg <mrg%NetBSD.org@localhost>
date:      Tue Mar 30 11:42:04 2004 +0000

description:
factor out filetype checking code

diffstat:

 usr.bin/gzip/gzip.c |  59 +++++++++++++++++++++++++++++++---------------------
 1 files changed, 35 insertions(+), 24 deletions(-)

diffs (100 lines):

diff -r 700001d9997c -r 712fb4cbe45a usr.bin/gzip/gzip.c
--- a/usr.bin/gzip/gzip.c       Tue Mar 30 11:12:32 2004 +0000
+++ b/usr.bin/gzip/gzip.c       Tue Mar 30 11:42:04 2004 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: gzip.c,v 1.31 2004/03/30 09:42:58 mrg Exp $    */
+/*     $NetBSD: gzip.c,v 1.32 2004/03/30 11:42:04 mrg Exp $    */
 
 /*
  * Copyright (c) 1997, 1998, 2003 Matthew R. Green
@@ -32,7 +32,7 @@
 #ifndef lint
 __COPYRIGHT("@(#) Copyright (c) 1997, 1998, 2003 Matthew R. Green\n\
      All rights reserved.\n");
-__RCSID("$NetBSD: gzip.c,v 1.31 2004/03/30 09:42:58 mrg Exp $");
+__RCSID("$NetBSD: gzip.c,v 1.32 2004/03/30 11:42:04 mrg Exp $");
 #endif /* not lint */
 
 /*
@@ -133,6 +133,7 @@
 static void    maybe_errx(int rv, const char *fmt, ...);
 static void    maybe_warn(const char *fmt, ...);
 static void    maybe_warnx(const char *fmt, ...);
+static enum filetype file_gettype(u_char *);
 static void    gz_compress(FILE *, gzFile);
 static off_t   gz_uncompress(gzFile, FILE *);
 static off_t   file_compress(char *);
@@ -537,6 +538,29 @@
 }
 #endif
 
+/* what sort of file is this? */
+static enum filetype
+file_gettype(u_char *buf)
+{
+
+       if (buf[0] == GZIP_MAGIC0 &&
+           (buf[1] == GZIP_MAGIC1 || buf[1] == GZIP_OMAGIC1))
+               return FT_GZIP;
+       else
+#ifndef NO_BZIP2_SUPPORT
+       if (memcmp(buf, BZIP2_MAGIC, 3) == 0 &&
+           buf[3] >= '0' && buf[3] <= '9')
+               return FT_BZIP2;
+       else
+#endif
+#ifndef NO_COMPRESS_SUPPORT
+       if (memcmp(buf, Z_MAGIC, 2) == 0)
+               return FT_Z;
+       else
+#endif
+               return FT_UNKNOWN;
+}
+
 /*
  * compress the given file: create a corresponding .gz file and remove the
  * original.
@@ -664,34 +688,21 @@
                maybe_err(1, "can't read %s", file);
        }
 
-       if (header1[0] == GZIP_MAGIC0 &&
-           (header1[1] == GZIP_MAGIC1 || header1[1] == GZIP_OMAGIC1))
-               method = FT_GZIP;
-       else
+       method = file_gettype(header1);
 
-#ifndef NO_BZIP2_SUPPORT
-       if (memcmp(header1, BZIP2_MAGIC, 3) == 0 &&
-           header1[3] >= '0' && header1[3] <= '9') {
-# ifndef SMALL
-               if (Sflag == NULL)
+#ifndef SMALL
+       if (Sflag == NULL) {
+# ifndef NO_BZIP2_SUPPORT
+               if (method == FT_BZIP2)
                        suffix = BZ2_SUFFIX;
-               method = FT_BZIP2;
+               else
 # endif
-       } else
-#endif
-
-#ifndef NO_COMPRESS_SUPPORT
-       if (memcmp(header1, Z_MAGIC, 2) == 0) {
-# ifndef SMALL
-               if (Sflag == NULL)
+# ifndef NO_COMPRESS_SUPPORT
+               if (method == FT_Z)
                        suffix = Z_SUFFIX;
 # endif
-               method = FT_Z;
-       } else
-#endif
-               method = FT_UNKNOWN;
+       }
 
-#ifndef SMALL
        if (fflag == 0 && method == FT_UNKNOWN)
                maybe_errx(1, "%s: not in gzip format", file);
 #endif