Add Lzip support

[chaz/tar] / src / buffer.c

diff --git a/src/buffer.c b/src/buffer.c
index ed7530342398c15f316c3c2e372db25a3c81a7f3..8147def1961246dfdef3f3704432416431c6f932 100644 (file)
--- a/src/buffer.c
+++ b/src/buffer.c
@@ -36,9 +36,6 @@
 /* Number of retries before giving up on read.  */
 #define READ_ERROR_MAX 10
 
-/* Globbing pattern to append to volume label if initial match failed.  */
-#define VOLUME_LABEL_APPEND " Volume [1-9]*"
-
 /* Variables.  */
 
 static tarlong prev_written;    /* bytes written on previous volumes */
@@ -204,6 +201,7 @@ enum compress_type {
   ct_compress,
   ct_gzip,
   ct_bzip2,
+  ct_lzip,
   ct_lzma,
   ct_lzop,
   ct_xz
@@ -224,6 +222,7 @@ static struct zip_magic const magic[] = {
   { ct_compress, 2, "\037\235",  COMPRESS_PROGRAM, "-Z" },
   { ct_gzip,     2, "\037\213",  GZIP_PROGRAM,     "-z"  },
   { ct_bzip2,    3, "BZh",       BZIP2_PROGRAM,    "-j" },
+  { ct_lzip,     4, "LZIP",      LZIP_PROGRAM,     "--lzip" },
   { ct_lzma,     6, "\xFFLZMA",  LZMA_PROGRAM,     "--lzma" },
   { ct_lzop,     4, "\211LZO",   LZOP_PROGRAM,     "--lzop" },
   { ct_xz,       6, "\0xFD7zXZ", XZ_PROGRAM,       "-J" },
@@ -857,16 +856,16 @@ seek_archive (off_t size)
   off_t start = current_block_ordinal ();
   off_t offset;
   off_t nrec, nblk;
-  off_t skipped = (blocking_factor - (current_block - record_start));
-
-  size -= skipped * BLOCKSIZE;
+  off_t skipped = (blocking_factor - (current_block - record_start))
+                  * BLOCKSIZE;
 
-  if (size < record_size)
+  if (size <= skipped)
     return 0;
-  /* FIXME: flush? */
-
+  
   /* Compute number of records to skip */
-  nrec = size / record_size;
+  nrec = (size - skipped) / record_size;
+  if (nrec == 0)
+    return 0;
   offset = rmtlseek (archive, nrec * record_size, SEEK_CUR);
   if (offset < 0)
     return offset;
@@ -1168,7 +1167,7 @@ read_header0 (struct tar_stat_info *info)
   enum read_header rc;
 
   tar_stat_init (info);
-  rc = read_header (&current_header, info, false);
+  rc = read_header (&current_header, info, read_header_auto);
   if (rc == HEADER_SUCCESS)
     {
       set_next_block_after (current_header);
@@ -1216,17 +1215,42 @@ try_new_volume ()
     {
     case XGLTYPE:
       {
-        if (!read_header0 (&dummy))
-          return false;
+       tar_stat_init (&dummy);
+       if (read_header (&header, &dummy, read_header_x_global)
+           != HEADER_SUCCESS_EXTENDED)
+         {
+           ERROR ((0, 0, _("This does not look like a tar archive")));
+           return false;
+         }
+       
         xheader_decode (&dummy); /* decodes values from the global header */
         tar_stat_destroy (&dummy);
-        if (!real_s_name)
-          {
-            /* We have read the extended header of the first member in
-               this volume. Put it back, so next read_header works as
-               expected. */
-            current_block = record_start;
-          }
+       
+       /* The initial global header must be immediately followed by
+          an extended PAX header for the first member in this volume.
+          However, in some cases tar may split volumes in the middle
+          of a PAX header. This is incorrect, and should be fixed
+           in the future versions. In the meantime we must be
+          prepared to correctly list and extract such archives.
+
+          If this happens, the following call to read_header returns
+          HEADER_FAILURE, which is ignored.
+
+          See also tests/multiv07.at */
+              
+       switch (read_header (&header, &dummy, read_header_auto))
+         {
+         case HEADER_SUCCESS:
+           set_next_block_after (header);
+           break;
+
+         case HEADER_FAILURE:
+           break;
+
+         default:
+           ERROR ((0, 0, _("This does not look like a tar archive")));
+           return false;
+         }
         break;
       }
 
@@ -1313,6 +1337,35 @@ try_new_volume ()
 }
 
 \f
+#define VOLUME_TEXT " Volume "
+#define VOLUME_TEXT_LEN (sizeof VOLUME_TEXT - 1)
+
+char *
+drop_volume_label_suffix (const char *label)
+{
+  const char *p;
+  size_t len = strlen (label);
+
+  if (len < 1)
+    return NULL;
+  
+  for (p = label + len - 1; p > label && isdigit ((unsigned char) *p); p--)
+    ;
+  if (p > label && p - (VOLUME_TEXT_LEN - 1) > label)
+    {
+      p -= VOLUME_TEXT_LEN - 1;
+      if (memcmp (p, VOLUME_TEXT, VOLUME_TEXT_LEN) == 0)
+       {
+         char *s = xmalloc ((len = p - label) + 1);
+         memcpy (s, label, len);
+         s[len] = 0;
+         return s;
+       }
+    }
+
+  return NULL;
+}
+      
 /* Check LABEL against the volume label, seen as a globbing
    pattern.  Return true if the pattern matches.  In case of failure,
    retry matching a volume sequence number before giving up in
@@ -1329,12 +1382,12 @@ check_label_pattern (const char *label)
   if (!multi_volume_option)
     return false;
 
-  string = xmalloc (strlen (volume_label_option)
-                    + sizeof VOLUME_LABEL_APPEND + 1);
-  strcpy (string, volume_label_option);
-  strcat (string, VOLUME_LABEL_APPEND);
-  result = fnmatch (string, label, 0) == 0;
-  free (string);
+  string = drop_volume_label_suffix (label);
+  if (string)
+    {
+      result = fnmatch (string, volume_label_option, 0) == 0;
+      free (string);
+    }
   return result;
 }