cleanup: split tar code up, remove some duplications

This commit attempts to split some of the monolitic tar parsing code up
into multiple functions in seperate files. Also, some code duplication
(like reading a record into memory which was implemented twice) is
removed.

Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>

1 files changed, 55 insertions, 0 deletions

diff --git a/lib/tar/internal.h b/lib/tar/internal.h
new file mode 100644
index 0000000..6596987
--- /dev/null
+++ b/lib/tar/internal.h
@@ -0,0 +1,55 @@
+/* SPDX-License-Identifier: GPL-3.0-or-later */
+#ifndef INTERNAL_H
+#define INTERNAL_H
+
+#include "util.h"
+#include "tar.h"
+
+#include <sys/sysmacros.h>
+#include <string.h>
+#include <stdlib.h>
+#include <ctype.h>
+#include <stdio.h>
+
+enum {
+	PAX_SIZE = 0x001,
+	PAX_UID = 0x002,
+	PAX_GID = 0x004,
+	PAX_DEV_MAJ = 0x008,
+	PAX_DEV_MIN = 0x010,
+	PAX_NAME = 0x020,
+	PAX_SLINK_TARGET = 0x040,
+	PAX_ATIME = 0x080,
+	PAX_MTIME = 0x100,
+	PAX_CTIME = 0x200,
+	PAX_SPARSE_SIZE = 0x400,
+};
+
+enum {
+	ETV_UNKNOWN = 0,
+	ETV_V7_UNIX,
+	ETV_PRE_POSIX,
+	ETV_POSIX,
+};
+
+int read_octal(const char *str, int digits, uint64_t *out);
+
+int read_binary(const char *str, int digits, uint64_t *out);
+
+int read_number(const char *str, int digits, uint64_t *out);
+
+void write_octal(char *dst, unsigned int value, int digits);
+
+int pax_read_decimal(const char *str, uint64_t *out);
+
+void update_checksum(tar_header_t *hdr);
+
+bool is_checksum_valid(const tar_header_t *hdr);
+
+sparse_map_t *read_sparse_map(const char *line);
+
+sparse_map_t *read_gnu_old_sparse(int fd, tar_header_t *hdr);
+
+void free_sparse_list(sparse_map_t *sparse);
+
+#endif /* INTERNAL_H */