tar-1.29HEADtar-1.29master

1 files changed, 379 insertions, 0 deletions

diff --git a/src/tar.h b/src/tar.h
new file mode 100644
index 0000000..07b5bc1
--- /dev/null
+++ b/src/tar.h
@@ -0,0 +1,379 @@
+/* GNU tar Archive Format description.
+
+   Copyright 1988-1989, 1991-1997, 2000-2001, 2003-2007, 2012-2014, 2016
+   Free Software Foundation, Inc.
+
+   This file is part of GNU tar.
+
+   GNU tar is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 3 of the License, or
+   (at your option) any later version.
+
+   GNU tar is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
+
+/* tar Header Block, from POSIX 1003.1-1990.  */
+
+/* POSIX header.  */
+
+struct posix_header
+{				/* byte offset */
+  char name[100];		/*   0 */
+  char mode[8];			/* 100 */
+  char uid[8];			/* 108 */
+  char gid[8];			/* 116 */
+  char size[12];		/* 124 */
+  char mtime[12];		/* 136 */
+  char chksum[8];		/* 148 */
+  char typeflag;		/* 156 */
+  char linkname[100];		/* 157 */
+  char magic[6];		/* 257 */
+  char version[2];		/* 263 */
+  char uname[32];		/* 265 */
+  char gname[32];		/* 297 */
+  char devmajor[8];		/* 329 */
+  char devminor[8];		/* 337 */
+  char prefix[155];		/* 345 */
+				/* 500 */
+};
+
+#define TMAGIC   "ustar"	/* ustar and a null */
+#define TMAGLEN  6
+#define TVERSION "00"		/* 00 and no null */
+#define TVERSLEN 2
+
+/* Values used in typeflag field.  */
+#define REGTYPE	 '0'		/* regular file */
+#define AREGTYPE '\0'		/* regular file */
+#define LNKTYPE  '1'		/* link */
+#define SYMTYPE  '2'		/* reserved */
+#define CHRTYPE  '3'		/* character special */
+#define BLKTYPE  '4'		/* block special */
+#define DIRTYPE  '5'		/* directory */
+#define FIFOTYPE '6'		/* FIFO special */
+#define CONTTYPE '7'		/* reserved */
+
+#define XHDTYPE  'x'            /* Extended header referring to the
+				   next file in the archive */
+#define XGLTYPE  'g'            /* Global extended header */
+
+/* Bits used in the mode field, values in octal.  */
+#define TSUID    04000		/* set UID on execution */
+#define TSGID    02000		/* set GID on execution */
+#define TSVTX    01000		/* reserved */
+				/* file permissions */
+#define TUREAD   00400		/* read by owner */
+#define TUWRITE  00200		/* write by owner */
+#define TUEXEC   00100		/* execute/search by owner */
+#define TGREAD   00040		/* read by group */
+#define TGWRITE  00020		/* write by group */
+#define TGEXEC   00010		/* execute/search by group */
+#define TOREAD   00004		/* read by other */
+#define TOWRITE  00002		/* write by other */
+#define TOEXEC   00001		/* execute/search by other */
+
+/* tar Header Block, GNU extensions.  */
+
+/* In GNU tar, SYMTYPE is for to symbolic links, and CONTTYPE is for
+   contiguous files, so maybe disobeying the "reserved" comment in POSIX
+   header description.  I suspect these were meant to be used this way, and
+   should not have really been "reserved" in the published standards.  */
+
+/* *BEWARE* *BEWARE* *BEWARE* that the following information is still
+   boiling, and may change.  Even if the OLDGNU format description should be
+   accurate, the so-called GNU format is not yet fully decided.  It is
+   surely meant to use only extensions allowed by POSIX, but the sketch
+   below repeats some ugliness from the OLDGNU format, which should rather
+   go away.  Sparse files should be saved in such a way that they do *not*
+   require two passes at archive creation time.  Huge files get some POSIX
+   fields to overflow, alternate solutions have to be sought for this.  */
+
+/* Descriptor for a single file hole.  */
+
+struct sparse
+{				/* byte offset */
+  char offset[12];		/*   0 */
+  char numbytes[12];		/*  12 */
+				/*  24 */
+};
+
+/* Sparse files are not supported in POSIX ustar format.  For sparse files
+   with a POSIX header, a GNU extra header is provided which holds overall
+   sparse information and a few sparse descriptors.  When an old GNU header
+   replaces both the POSIX header and the GNU extra header, it holds some
+   sparse descriptors too.  Whether POSIX or not, if more sparse descriptors
+   are still needed, they are put into as many successive sparse headers as
+   necessary.  The following constants tell how many sparse descriptors fit
+   in each kind of header able to hold them.  */
+
+#define SPARSES_IN_EXTRA_HEADER  16
+#define SPARSES_IN_OLDGNU_HEADER 4
+#define SPARSES_IN_SPARSE_HEADER 21
+
+/* Extension header for sparse files, used immediately after the GNU extra
+   header, and used only if all sparse information cannot fit into that
+   extra header.  There might even be many such extension headers, one after
+   the other, until all sparse information has been recorded.  */
+
+struct sparse_header
+{				/* byte offset */
+  struct sparse sp[SPARSES_IN_SPARSE_HEADER];
+				/*   0 */
+  char isextended;		/* 504 */
+				/* 505 */
+};
+
+/* The old GNU format header conflicts with POSIX format in such a way that
+   POSIX archives may fool old GNU tar's, and POSIX tar's might well be
+   fooled by old GNU tar archives.  An old GNU format header uses the space
+   used by the prefix field in a POSIX header, and cumulates information
+   normally found in a GNU extra header.  With an old GNU tar header, we
+   never see any POSIX header nor GNU extra header.  Supplementary sparse
+   headers are allowed, however.  */
+
+struct oldgnu_header
+{				/* byte offset */
+  char unused_pad1[345];	/*   0 */
+  char atime[12];		/* 345 Incr. archive: atime of the file */
+  char ctime[12];		/* 357 Incr. archive: ctime of the file */
+  char offset[12];		/* 369 Multivolume archive: the offset of
+				   the start of this volume */
+  char longnames[4];		/* 381 Not used */
+  char unused_pad2;		/* 385 */
+  struct sparse sp[SPARSES_IN_OLDGNU_HEADER];
+				/* 386 */
+  char isextended;		/* 482 Sparse file: Extension sparse header
+				   follows */
+  char realsize[12];		/* 483 Sparse file: Real size*/
+				/* 495 */
+};
+
+/* OLDGNU_MAGIC uses both magic and version fields, which are contiguous.
+   Found in an archive, it indicates an old GNU header format, which will be
+   hopefully become obsolescent.  With OLDGNU_MAGIC, uname and gname are
+   valid, though the header is not truly POSIX conforming.  */
+#define OLDGNU_MAGIC "ustar  "	/* 7 chars and a null */
+
+/* The standards committee allows only capital A through capital Z for
+   user-defined expansion.  Other letters in use include:
+
+   'A' Solaris Access Control List
+   'E' Solaris Extended Attribute File
+   'I' Inode only, as in 'star'
+   'N' Obsolete GNU tar, for file names that do not fit into the main header.
+   'X' POSIX 1003.1-2001 eXtended (VU version)  */
+
+/* This is a dir entry that contains the names of files that were in the
+   dir at the time the dump was made.  */
+#define GNUTYPE_DUMPDIR	'D'
+
+/* Identifies the *next* file on the tape as having a long linkname.  */
+#define GNUTYPE_LONGLINK 'K'
+
+/* Identifies the *next* file on the tape as having a long name.  */
+#define GNUTYPE_LONGNAME 'L'
+
+/* This is the continuation of a file that began on another volume.  */
+#define GNUTYPE_MULTIVOL 'M'
+
+/* This is for sparse files.  */
+#define GNUTYPE_SPARSE 'S'
+
+/* This file is a tape/volume header.  Ignore it on extraction.  */
+#define GNUTYPE_VOLHDR 'V'
+
+/* Solaris extended header */
+#define SOLARIS_XHDTYPE 'X'
+
+/* J@"org Schilling star header */
+
+struct star_header
+{				/* byte offset */
+  char name[100];		/*   0 */
+  char mode[8];			/* 100 */
+  char uid[8];			/* 108 */
+  char gid[8];			/* 116 */
+  char size[12];		/* 124 */
+  char mtime[12];		/* 136 */
+  char chksum[8];		/* 148 */
+  char typeflag;		/* 156 */
+  char linkname[100];		/* 157 */
+  char magic[6];		/* 257 */
+  char version[2];		/* 263 */
+  char uname[32];		/* 265 */
+  char gname[32];		/* 297 */
+  char devmajor[8];		/* 329 */
+  char devminor[8];		/* 337 */
+  char prefix[131];		/* 345 */
+  char atime[12];               /* 476 */
+  char ctime[12];               /* 488 */
+                                /* 500 */
+};
+
+#define SPARSES_IN_STAR_HEADER      4
+#define SPARSES_IN_STAR_EXT_HEADER  21
+
+struct star_in_header
+{
+  char fill[345];       /*   0  Everything that is before t_prefix */
+  char prefix[1];       /* 345  t_name prefix */
+  char fill2;           /* 346  */
+  char fill3[8];        /* 347  */
+  char isextended;      /* 355  */
+  struct sparse sp[SPARSES_IN_STAR_HEADER]; /* 356  */
+  char realsize[12];    /* 452  Actual size of the file */
+  char offset[12];      /* 464  Offset of multivolume contents */
+  char atime[12];       /* 476  */
+  char ctime[12];       /* 488  */
+  char mfill[8];        /* 500  */
+  char xmagic[4];       /* 508  "tar" */
+};
+
+struct star_ext_header
+{
+  struct sparse sp[SPARSES_IN_STAR_EXT_HEADER];
+  char isextended;
+};
+
+/* END */
+
+
+/* tar Header Block, overall structure.  */
+
+/* tar files are made in basic blocks of this size.  */
+#define BLOCKSIZE 512
+
+enum archive_format
+{
+  DEFAULT_FORMAT,		/* format to be decided later */
+  V7_FORMAT,			/* old V7 tar format */
+  OLDGNU_FORMAT,		/* GNU format as per before tar 1.12 */
+  USTAR_FORMAT,                 /* POSIX.1-1988 (ustar) format */
+  POSIX_FORMAT,			/* POSIX.1-2001 format */
+  STAR_FORMAT,                  /* Star format defined in 1994 */
+  GNU_FORMAT			/* Same as OLDGNU_FORMAT with one exception:
+                                   see FIXME note for to_chars() function
+                                   (create.c:189) */
+};
+
+/* Information about a sparse file.  */
+struct sp_array
+{
+  off_t offset;
+  off_t numbytes;
+};
+
+struct xheader
+{
+  struct obstack *stk;
+  size_t size;
+  char *buffer;
+  uintmax_t string_length;
+};
+
+/* Information about xattrs for a file.  */
+struct xattr_array
+  {
+    char *xkey;
+    char *xval_ptr;
+    size_t xval_len;
+  };
+
+struct tar_stat_info
+{
+  char *orig_file_name;     /* name of file read from the archive header */
+  char *file_name;          /* name of file for the current archive entry
+			       after being normalized.  */
+  bool had_trailing_slash;  /* true if the current archive entry had a
+			       trailing slash before it was normalized. */
+  char *link_name;          /* name of link for the current archive entry.  */
+
+  char          *uname;     /* user name of owner */
+  char          *gname;     /* group name of owner */
+
+  char *cntx_name;          /* SELinux context for the current archive entry. */
+
+  char *acls_a_ptr;         /* Access ACLs for the current archive entry. */
+  size_t acls_a_len;        /* Access ACLs for the current archive entry. */
+
+  char *acls_d_ptr;         /* Default ACLs for the current archive entry. */
+  size_t acls_d_len;        /* Default ACLs for the current archive entry. */
+
+  struct stat   stat;       /* regular filesystem stat */
+
+  /* STAT doesn't always have access, data modification, and status
+     change times in a convenient form, so store them separately.  */
+  struct timespec atime;
+  struct timespec mtime;
+  struct timespec ctime;
+
+  off_t archive_file_size;  /* Size of file as stored in the archive.
+			       Equals stat.st_size for non-sparse files */
+
+  bool   is_sparse;         /* Is the file sparse */
+
+  /* For sparse files: */
+  unsigned sparse_major;
+  unsigned sparse_minor;
+  size_t sparse_map_avail;  /* Index to the first unused element in
+			       sparse_map array. Zero if the file is
+			       not sparse */
+  size_t sparse_map_size;   /* Size of the sparse map */
+  struct sp_array *sparse_map;
+
+  off_t real_size;          /* The real size of sparse file */
+  int   real_size_set;      /* True when GNU.sparse.realsize is set in
+			       archived file */
+
+  size_t xattr_map_size;   /* Size of the xattr map */
+  struct xattr_array *xattr_map;
+
+  /* Extended headers */
+  struct xheader xhdr;
+
+  /* For dumpdirs */
+  bool is_dumpdir;          /* Is the member a dumpdir? */
+  bool skipped;             /* The member contents is already read
+			       (for GNUTYPE_DUMPDIR) */
+  char *dumpdir;            /* Contents of the dump directory */
+
+  /* Parent directory, if creating an archive.  This is null if the
+     file is at the top level.  */
+  struct tar_stat_info *parent;
+
+  /* Directory stream.  If this is not null, it is in control of FD,
+     and should be closed instead of FD.  */
+  DIR *dirstream;
+
+  /* File descriptor, if creating an archive, and if a directory or a
+     regular file or a contiguous file.
+
+     It is zero if no file descriptor is available, either because it
+     was never needed or because it was open and then closed to
+     conserve on file descriptors.  (Standard input is never used
+     here, so zero cannot be a valid file descriptor.)
+
+     It is negative if it could not be reopened after it was closed.
+     Negate it to find out what errno was when the reopen failed.  */
+  int fd;
+
+  /* Exclusion list */
+  struct exclist *exclude_list;
+};
+
+union block
+{
+  char buffer[BLOCKSIZE];
+  struct posix_header header;
+  struct star_header star_header;
+  struct oldgnu_header oldgnu_header;
+  struct sparse_header sparse_header;
+  struct star_in_header star_in_header;
+  struct star_ext_header star_ext_header;
+};