Merging upstream version 1.13~rc1.

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 20 insertions, 18 deletions

diff --git a/zutils.cc b/zutils.cc
index 48e4a56..14fe6c3 100644
--- a/zutils.cc
+++ b/zutils.cc
@@ -244,7 +244,7 @@ bool set_data_feeder( const std::string & filename, int * const infdp,
   }
 
 
-// Return format_index, or -1 if uncompressed.
+// Return format_index, or -1 if uncompressed or shorter than magic_buf_size.
 //
 int test_format( const int infd, uint8_t magic_data[],
                  int * const magic_sizep )
@@ -269,22 +269,24 @@ int test_format( const int infd, uint8_t magic_data[],
     { 0x28, 0xB5, 0x2F, 0xFD };				// 0xFD2FB528 LE
 
   *magic_sizep = readblock( infd, magic_data, magic_buf_size );
-  if( *magic_sizep == magic_buf_size )	// test formats in search order
-    {
-    if( std::memcmp( magic_data, lzip_magic, lzip_magic_size ) == 0 &&
-        isvalid_ds( magic_data[lzip_magic_size] ) )
-      return fmt_lz;
-    if( std::memcmp( magic_data, bzip2_magic, bzip2_magic_size ) == 0 &&
-        magic_data[3] >= '1' && magic_data[3] <= '9' &&
-        std::memcmp( magic_data + 4, "1AY&SY", 6 ) == 0 )
-      return fmt_bz2;
-    if( std::memcmp( magic_data, gzip_magic, gzip_magic_size ) == 0 ||
-        std::memcmp( magic_data, compress_magic, compress_magic_size ) == 0 )
-      return fmt_gz;
-    if( std::memcmp( magic_data, zstd_magic, zstd_magic_size ) == 0 )
-      return fmt_zst;
-    if( std::memcmp( magic_data, xz_magic, xz_magic_size ) == 0 )
-      return fmt_xz;
-    }
+  if( *magic_sizep < magic_buf_size )
+    { if( errno ) return -1;				// read error
+      for( int i = *magic_sizep; i < magic_buf_size; ++i ) magic_data[i] = 0; }
+  // test formats in search order
+  if( std::memcmp( magic_data, lzip_magic, lzip_magic_size ) == 0 &&
+      isvalid_ds( magic_data[lzip_magic_size] ) )
+    return fmt_lz;
+  if( std::memcmp( magic_data, bzip2_magic, bzip2_magic_size ) == 0 &&
+      magic_data[3] >= '1' && magic_data[3] <= '9' &&
+      ( std::memcmp( magic_data + 4, "1AY&SY", 6 ) == 0 ||
+        std::memcmp( magic_data + 4, "\x17rE8P\x90", 6 ) == 0 ) )
+    return fmt_bz2;
+  if( std::memcmp( magic_data, gzip_magic, gzip_magic_size ) == 0 ||
+      std::memcmp( magic_data, compress_magic, compress_magic_size ) == 0 )
+    return fmt_gz;
+  if( std::memcmp( magic_data, zstd_magic, zstd_magic_size ) == 0 )
+    return fmt_zst;
+  if( std::memcmp( magic_data, xz_magic, xz_magic_size ) == 0 )
+    return fmt_xz;
   return -1;
   }