libunarchive: stop using static data in archivers - archive_handle_t

 can trivially provide space for that.
rpm: code shrink
tar: simplify autodetection of bz2/.gz


function                                             old     new   delta
static.not_first                                       1       -      -1
static.end                                             1       -      -1
bb_makedev                                            51      49      -2
static.saved_hardlinks_created                         4       -      -4
static.saved_hardlinks                                 4       -      -4
longname                                               4       -      -4
linkname                                               4       -      -4
hash_file                                            251     247      -4
get_header_tar                                      1528    1521      -7
rpm_main                                            1711    1697     -14
get_header_cpio                                      965     944     -21
------------------------------------------------------------------------------
(add/remove: 0/6 grow/shrink: 0/5 up/down: 0/-66)             Total: -66 bytes
   text    data     bss     dec     hex filename
 804926     611    6868  812405   c6575 busybox_old
 804878     611    6852  812341   c6535 busybox_unstripped

11 files changed, 89 insertions, 86 deletions

diff --git a/archival/ar.c b/archival/ar.c
index ddc12095c..d49329ce9 100644
--- a/archival/ar.c
+++ b/archival/ar.c
@@ -63,7 +63,7 @@ int ar_main(int argc, char **argv)
                 archive_handle->action_data = data_extract_all;
         }
         if (opt & AR_OPT_PRESERVE_DATE) {
-                archive_handle->flags |= ARCHIVE_PRESERVE_DATE;
+                archive_handle->ah_flags |= ARCHIVE_PRESERVE_DATE;
         }
         if (opt & AR_OPT_VERBOSE) {
                 archive_handle->action_header = header_verbose_list_ar;
diff --git a/archival/cpio.c b/archival/cpio.c
index 0147d0e96..a10bfa85f 100644
--- a/archival/cpio.c
+++ b/archival/cpio.c
@@ -204,7 +204,7 @@ int cpio_main(int argc ATTRIBUTE_UNUSED, char **argv)
         archive_handle = init_handle();
         archive_handle->src_fd = STDIN_FILENO;
         archive_handle->seek = seek_by_read;
-        archive_handle->flags = ARCHIVE_EXTRACT_NEWER;
+        archive_handle->ah_flags = ARCHIVE_EXTRACT_NEWER;
 
 #if ENABLE_FEATURE_CPIO_O
         opt = getopt32(argv, "ituvF:dmoH:", &cpio_filename, &cpio_fmt);
@@ -241,8 +241,8 @@ int cpio_main(int argc ATTRIBUTE_UNUSED, char **argv)
                 archive_handle->action_data = data_extract_all;
         }
         if (opt & CPIO_OPT_UNCONDITIONAL) {
-                archive_handle->flags |= ARCHIVE_EXTRACT_UNCONDITIONAL;
-                archive_handle->flags &= ~ARCHIVE_EXTRACT_NEWER;
+                archive_handle->ah_flags |= ARCHIVE_EXTRACT_UNCONDITIONAL;
+                archive_handle->ah_flags &= ~ARCHIVE_EXTRACT_NEWER;
         }
         if (opt & CPIO_OPT_VERBOSE) {
                 if (archive_handle->action_header == header_list) {
@@ -256,10 +256,10 @@ int cpio_main(int argc ATTRIBUTE_UNUSED, char **argv)
                 archive_handle->seek = seek_by_jump;
         }
         if (opt & CPIO_OPT_CREATE_LEADING_DIR) {
-                archive_handle->flags |= ARCHIVE_CREATE_LEADING_DIRS;
+                archive_handle->ah_flags |= ARCHIVE_CREATE_LEADING_DIRS;
         }
         if (opt & CPIO_OPT_PRESERVE_MTIME) {
-                archive_handle->flags |= ARCHIVE_PRESERVE_DATE;
+                archive_handle->ah_flags |= ARCHIVE_PRESERVE_DATE;
         }
 
         while (*argv) {
diff --git a/archival/dpkg.c b/archival/dpkg.c
index 34e5f80e4..22e26f566 100644
--- a/archival/dpkg.c
+++ b/archival/dpkg.c
@@ -1532,7 +1532,7 @@ static void unpack_package(deb_file_t *deb_file)
         archive_handle->sub_archive->filter = filter_accept_list;
         archive_handle->sub_archive->action_data = data_extract_all_prefix;
         archive_handle->sub_archive->buffer = info_prefix;
-        archive_handle->sub_archive->flags |= ARCHIVE_EXTRACT_UNCONDITIONAL;
+        archive_handle->sub_archive->ah_flags |= ARCHIVE_EXTRACT_UNCONDITIONAL;
         unpack_ar_archive(archive_handle);
 
         /* Run the preinst prior to extracting */
@@ -1543,7 +1543,7 @@ static void unpack_package(deb_file_t *deb_file)
         init_archive_deb_data(archive_handle);
         archive_handle->sub_archive->action_data = data_extract_all_prefix;
         archive_handle->sub_archive->buffer = (char*)"/"; /* huh? */
-        archive_handle->sub_archive->flags |= ARCHIVE_EXTRACT_UNCONDITIONAL;
+        archive_handle->sub_archive->ah_flags |= ARCHIVE_EXTRACT_UNCONDITIONAL;
         unpack_ar_archive(archive_handle);
 
         /* Create the list file */
diff --git a/archival/libunarchive/data_extract_all.c b/archival/libunarchive/data_extract_all.c
index 1b4876799..a67587d72 100644
--- a/archival/libunarchive/data_extract_all.c
+++ b/archival/libunarchive/data_extract_all.c
@@ -12,14 +12,14 @@ void FAST_FUNC data_extract_all(archive_handle_t *archive_handle)
         int dst_fd;
         int res;
 
-        if (archive_handle->flags & ARCHIVE_CREATE_LEADING_DIRS) {
+        if (archive_handle->ah_flags & ARCHIVE_CREATE_LEADING_DIRS) {
                 char *name = xstrdup(file_header->name);
                 bb_make_directory(dirname(name), -1, FILEUTILS_RECUR);
                 free(name);
         }
 
         /* Check if the file already exists */
-        if (archive_handle->flags & ARCHIVE_EXTRACT_UNCONDITIONAL) {
+        if (archive_handle->ah_flags & ARCHIVE_EXTRACT_UNCONDITIONAL) {
                 /* Remove the entry if it exists */
                 if (((file_header->mode & S_IFMT) != S_IFDIR)
                  && (unlink(file_header->name) == -1)
@@ -29,7 +29,7 @@ void FAST_FUNC data_extract_all(archive_handle_t *archive_handle)
                                         file_header->name);
                 }
         }
-        else if (archive_handle->flags & ARCHIVE_EXTRACT_NEWER) {
+        else if (archive_handle->ah_flags & ARCHIVE_EXTRACT_NEWER) {
                 /* Remove the existing entry if its older than the extracted entry */
                 struct stat statbuf;
                 if (lstat(file_header->name, &statbuf) == -1) {
@@ -38,7 +38,7 @@ void FAST_FUNC data_extract_all(archive_handle_t *archive_handle)
                         }
                 }
                 else if (statbuf.st_mtime <= file_header->mtime) {
-                        if (!(archive_handle->flags & ARCHIVE_EXTRACT_QUIET)) {
+                        if (!(archive_handle->ah_flags & ARCHIVE_EXTRACT_QUIET)) {
                                 bb_error_msg("%s not created: newer or "
                                         "same age file exists", file_header->name);
                         }
@@ -58,7 +58,7 @@ void FAST_FUNC data_extract_all(archive_handle_t *archive_handle)
         ) {
                 /* hard link */
                 res = link(file_header->link_target, file_header->name);
-                if ((res == -1) && !(archive_handle->flags & ARCHIVE_EXTRACT_QUIET)) {
+                if ((res == -1) && !(archive_handle->ah_flags & ARCHIVE_EXTRACT_QUIET)) {
                         bb_perror_msg("cannot create %slink "
                                         "from %s to %s", "hard",
                                         file_header->name,
@@ -78,7 +78,7 @@ void FAST_FUNC data_extract_all(archive_handle_t *archive_handle)
                 case S_IFDIR:
                         res = mkdir(file_header->name, file_header->mode);
                         if ((res == -1) && (errno != EISDIR)
-                         && !(archive_handle->flags & ARCHIVE_EXTRACT_QUIET)
+                         && !(archive_handle->ah_flags & ARCHIVE_EXTRACT_QUIET)
                         ) {
                                 bb_perror_msg("cannot make dir %s", file_header->name);
                         }
@@ -87,7 +87,7 @@ void FAST_FUNC data_extract_all(archive_handle_t *archive_handle)
                         /* Symlink */
                         res = symlink(file_header->link_target, file_header->name);
                         if ((res == -1)
-                         && !(archive_handle->flags & ARCHIVE_EXTRACT_QUIET)
+                         && !(archive_handle->ah_flags & ARCHIVE_EXTRACT_QUIET)
                         ) {
                                 bb_perror_msg("cannot create %slink "
                                         "from %s to %s", "sym",
@@ -101,7 +101,7 @@ void FAST_FUNC data_extract_all(archive_handle_t *archive_handle)
                 case S_IFIFO:
                         res = mknod(file_header->name, file_header->mode, file_header->device);
                         if ((res == -1)
-                         && !(archive_handle->flags & ARCHIVE_EXTRACT_QUIET)
+                         && !(archive_handle->ah_flags & ARCHIVE_EXTRACT_QUIET)
                         ) {
                                 bb_perror_msg("cannot create node %s", file_header->name);
                         }
@@ -111,7 +111,7 @@ void FAST_FUNC data_extract_all(archive_handle_t *archive_handle)
                 }
         }
 
-        if (!(archive_handle->flags & ARCHIVE_NOPRESERVE_OWN)) {
+        if (!(archive_handle->ah_flags & ARCHIVE_NOPRESERVE_OWN)) {
 #if ENABLE_FEATURE_TAR_UNAME_GNAME
                 uid_t uid = file_header->uid;
                 gid_t gid = file_header->gid;
@@ -133,11 +133,11 @@ void FAST_FUNC data_extract_all(archive_handle_t *archive_handle)
                 /* uclibc has no lchmod, glibc is even stranger -
                  * it has lchmod which seems to do nothing!
                  * so we use chmod... */
-                if (!(archive_handle->flags & ARCHIVE_NOPRESERVE_PERM)) {
+                if (!(archive_handle->ah_flags & ARCHIVE_NOPRESERVE_PERM)) {
                         chmod(file_header->name, file_header->mode);
                 }
                 /* same for utime */
-                if (archive_handle->flags & ARCHIVE_PRESERVE_DATE) {
+                if (archive_handle->ah_flags & ARCHIVE_PRESERVE_DATE) {
                         struct utimbuf t;
                         t.actime = t.modtime = file_header->mtime;
                         utime(file_header->name, &t);
diff --git a/archival/libunarchive/get_header_ar.c b/archival/libunarchive/get_header_ar.c
index 05222992d..59fd34c73 100644
--- a/archival/libunarchive/get_header_ar.c
+++ b/archival/libunarchive/get_header_ar.c
@@ -110,7 +110,7 @@ char FAST_FUNC get_header_ar(archive_handle_t *archive_handle)
                 archive_handle->action_header(typed);
                 if (archive_handle->sub_archive) {
                         while (archive_handle->action_data_subarchive(archive_handle->sub_archive) == EXIT_SUCCESS)
-                                /* repeat */;
+                                continue;
                 } else {
                         archive_handle->action_data(archive_handle);
                 }
diff --git a/archival/libunarchive/get_header_cpio.c b/archival/libunarchive/get_header_cpio.c
index 4ed18c68f..96be4b5ac 100644
--- a/archival/libunarchive/get_header_cpio.c
+++ b/archival/libunarchive/get_header_cpio.c
@@ -19,9 +19,6 @@ typedef struct hardlinks_s {
 
 char FAST_FUNC get_header_cpio(archive_handle_t *archive_handle)
 {
-        static hardlinks_t *saved_hardlinks = NULL;
-        static hardlinks_t *saved_hardlinks_created = NULL;
-
         file_header_t *file_header = archive_handle->file_header;
         char cpio_header[110];
         char dummy[16];
@@ -29,6 +26,14 @@ char FAST_FUNC get_header_cpio(archive_handle_t *archive_handle)
         int major, minor, nlink, mode, inode;
         unsigned size, uid, gid, mtime;
 
+#define saved_hardlinks         (*(hardlinks_t **)(&archive_handle->ah_priv[0]))
+#define saved_hardlinks_created (*(hardlinks_t **)(&archive_handle->ah_priv[1]))
+//      if (!archive_handle->ah_priv_inited) {
+//              archive_handle->ah_priv_inited = 1;
+//              saved_hardlinks = NULL;
+//              saved_hardlinks_created = NULL;
+//      }
+
         /* There can be padding before archive header */
         data_align(archive_handle, 4);
 
diff --git a/archival/libunarchive/get_header_tar.c b/archival/libunarchive/get_header_tar.c
index a0a53c908..69362f1cc 100644
--- a/archival/libunarchive/get_header_tar.c
+++ b/archival/libunarchive/get_header_tar.c
@@ -14,26 +14,13 @@
 #include "libbb.h"
 #include "unarchive.h"
 
-#if ENABLE_FEATURE_TAR_GNU_EXTENSIONS
-static char *longname;
-static char *linkname;
-#else
-enum {
-        longname = 0,
-        linkname = 0,
-};
-#endif
-
 /* NB: _DESTROYS_ str[len] character! */
 static unsigned long long getOctal(char *str, int len)
 {
         unsigned long long v;
-        /* Actually, tar header allows leading spaces also.
-         * Oh well, we will be liberal and skip this...
-         * The only downside probably is that we allow "-123" too :)
-        if (*str < '0' || *str > '7')
-                bb_error_msg_and_die("corrupted octal value in tar header");
-        */
+        /* NB: leading spaces are allowed. Using strtoull to handle that.
+         * The downside is that we accept e.g. "-123" too :)
+         */
         str[len] = '\0';
         v = strtoull(str, &str, 8);
         if (*str && (!ENABLE_FEATURE_TAR_OLDGNU_COMPATIBILITY || *str != ' '))
@@ -45,11 +32,6 @@ static unsigned long long getOctal(char *str, int len)
 void BUG_tar_header_size(void);
 char FAST_FUNC get_header_tar(archive_handle_t *archive_handle)
 {
-        static smallint end;
-#if ENABLE_FEATURE_TAR_AUTODETECT
-        static smallint not_first;
-#endif
-
         file_header_t *file_header = archive_handle->file_header;
         struct {
                 /* ustar header, Posix 1003.1 */
@@ -65,7 +47,7 @@ char FAST_FUNC get_header_tar(archive_handle_t *archive_handle)
                 /* POSIX:   "ustar" NUL "00" */
                 /* GNU tar: "ustar  " NUL */
                 /* Normally it's defined as magic[6] followed by
-                 * version[2], but we put them together to save code.
+                 * version[2], but we put them together to simplify code
                  */
                 char magic[8];      /* 257-264 */
                 char uname[32];     /* 265-296 */
@@ -82,6 +64,22 @@ char FAST_FUNC get_header_tar(archive_handle_t *archive_handle)
 #endif
         int parse_names;
 
+        /* Our "private data" */
+#define p_end (*(smallint *)(&archive_handle->ah_priv[0]))
+#if ENABLE_FEATURE_TAR_GNU_EXTENSIONS
+#define p_longname (*(char* *)(&archive_handle->ah_priv[1]))
+#define p_linkname (*(char* *)(&archive_handle->ah_priv[2]))
+#else
+#define p_longname 0
+#define p_linkname 0
+#endif
+//      if (!archive_handle->ah_priv_inited) {
+//              archive_handle->ah_priv_inited = 1;
+//              p_end = 0;
+//              USE_FEATURE_TAR_GNU_EXTENSIONS(p_longname = NULL;)
+//              USE_FEATURE_TAR_GNU_EXTENSIONS(p_linkname = NULL;)
+//      }
+
         if (sizeof(tar) != 512)
                 BUG_tar_header_size();
 
@@ -95,7 +93,7 @@ char FAST_FUNC get_header_tar(archive_handle_t *archive_handle)
 
 #if ENABLE_DESKTOP
         i = full_read(archive_handle->src_fd, &tar, 512);
-        /* if GNU tar sees EOF in above read, it says:
+        /* If GNU tar sees EOF in above read, it says:
          * "tar: A lone zero block at N", where N = kilobyte
          * where EOF was met (not EOF block, actual EOF!),
          * and tar will exit with error code 0.
@@ -113,18 +111,18 @@ char FAST_FUNC get_header_tar(archive_handle_t *archive_handle)
 
         /* If there is no filename its an empty header */
         if (tar.name[0] == 0 && tar.prefix[0] == 0) {
-                if (end) {
-                        /* This is the second consecutive empty header! End of archive!
+                if (p_end) {
+                        /* Second consecutive empty header - end of archive.
                          * Read until the end to empty the pipe from gz or bz2
                          */
                         while (full_read(archive_handle->src_fd, &tar, 512) == 512)
                                 continue;
                         return EXIT_FAILURE;
                 }
-                end = 1;
+                p_end = 1;
                 return EXIT_SUCCESS;
         }
-        end = 0;
+        p_end = 0;
 
         /* Check header has valid magic, "ustar" is for the proper tar,
          * five NULs are for the old tar format  */
@@ -136,12 +134,10 @@ char FAST_FUNC get_header_tar(archive_handle_t *archive_handle)
                 char FAST_FUNC (*get_header_ptr)(archive_handle_t *);
 
                 /* tar gz/bz autodetect: check for gz/bz2 magic.
-                 * If it is the very first block, and we see the magic,
+                 * If we see the magic, and it is the very first block,
                  * we can switch to get_header_tar_gz/bz2/lzma().
                  * Needs seekable fd. I wish recv(MSG_PEEK) works
                  * on any fd... */
-                if (not_first)
-                        goto err;
 #if ENABLE_FEATURE_TAR_GZIP
                 if (tar.name[0] == 0x1f && tar.name[1] == (char)0x8b) { /* gzip */
                         get_header_ptr = get_header_tar_gz;
@@ -155,6 +151,9 @@ char FAST_FUNC get_header_tar(archive_handle_t *archive_handle)
                 } else
 #endif
                         goto err;
+                /* Two different causes for lseek() != 0:
+                 * unseekable fd (would like to support that too, but...),
+                 * or not first block (false positive, it's not .gz/.bz2!) */
                 if (lseek(archive_handle->src_fd, -512, SEEK_CUR) != 0)
                         goto err;
                 while (get_header_ptr(archive_handle) == EXIT_SUCCESS)
@@ -165,10 +164,6 @@ char FAST_FUNC get_header_tar(archive_handle_t *archive_handle)
                 bb_error_msg_and_die("invalid tar magic");
         }
 
-#if ENABLE_FEATURE_TAR_AUTODETECT
-        not_first = 1;
-#endif
-
         /* Do checksum on headers.
          * POSIX says that checksum is done on unsigned bytes, but
          * Sun and HP-UX gets it wrong... more details in
@@ -219,7 +214,7 @@ char FAST_FUNC get_header_tar(archive_handle_t *archive_handle)
                 tar.prefix[0] = t;
         }
         file_header->link_target = NULL;
-        if (!linkname && parse_names && tar.linkname[0]) {
+        if (!p_linkname && parse_names && tar.linkname[0]) {
                 file_header->link_target = xstrndup(tar.linkname, sizeof(tar.linkname));
                 /* FIXME: what if we have non-link object with link_target? */
                 /* Will link_target be free()ed? */
@@ -236,7 +231,7 @@ char FAST_FUNC get_header_tar(archive_handle_t *archive_handle)
         file_header->mode = 07777 & GET_OCTAL(tar.mode);
 
         file_header->name = NULL;
-        if (!longname && parse_names) {
+        if (!p_longname && parse_names) {
                 /* we trash mode[0] here, it's ok */
                 //tar.name[sizeof(tar.name)] = '\0'; - gcc 4.3.0 would complain
                 tar.mode[0] = '\0';
@@ -284,20 +279,20 @@ char FAST_FUNC get_header_tar(archive_handle_t *archive_handle)
 #if ENABLE_FEATURE_TAR_GNU_EXTENSIONS
         case 'L':
                 /* free: paranoia: tar with several consecutive longnames */
-                free(longname);
+                free(p_longname);
                 /* For paranoia reasons we allocate extra NUL char */
-                longname = xzalloc(file_header->size + 1);
+                p_longname = xzalloc(file_header->size + 1);
                 /* We read ASCIZ string, including NUL */
-                xread(archive_handle->src_fd, longname, file_header->size);
+                xread(archive_handle->src_fd, p_longname, file_header->size);
                 archive_handle->offset += file_header->size;
                 /* return get_header_tar(archive_handle); */
                 /* gcc 4.1.1 didn't optimize it into jump */
                 /* so we will do it ourself, this also saves stack */
                 goto again;
         case 'K':
-                free(linkname);
-                linkname = xzalloc(file_header->size + 1);
-                xread(archive_handle->src_fd, linkname, file_header->size);
+                free(p_linkname);
+                p_linkname = xzalloc(file_header->size + 1);
+                xread(archive_handle->src_fd, p_linkname, file_header->size);
                 archive_handle->offset += file_header->size;
                 /* return get_header_tar(archive_handle); */
                 goto again;
@@ -324,13 +319,13 @@ char FAST_FUNC get_header_tar(archive_handle_t *archive_handle)
         }
 
 #if ENABLE_FEATURE_TAR_GNU_EXTENSIONS
-        if (longname) {
-                file_header->name = longname;
-                longname = NULL;
+        if (p_longname) {
+                file_header->name = p_longname;
+                p_longname = NULL;
         }
-        if (linkname) {
-                file_header->link_target = linkname;
-                linkname = NULL;
+        if (p_linkname) {
+                file_header->link_target = p_linkname;
+                p_linkname = NULL;
         }
 #endif
         if (!strncmp(file_header->name, "/../"+1, 3)
@@ -349,7 +344,7 @@ char FAST_FUNC get_header_tar(archive_handle_t *archive_handle)
                 /* Note that we kill the '/' only after action_header() */
                 /* (like GNU tar 1.15.1: verbose mode outputs "dir/dir/") */
                 if (cp) *cp = '\0';
-                archive_handle->flags |= ARCHIVE_EXTRACT_QUIET;
+                archive_handle->ah_flags |= ARCHIVE_EXTRACT_QUIET;
                 archive_handle->action_data(archive_handle);
                 llist_add_to(&(archive_handle->passed), file_header->name);
         } else {
diff --git a/archival/libunarchive/get_header_tar_lzma.c b/archival/libunarchive/get_header_tar_lzma.c
index 4ae125f4a..730c1b1bb 100644
--- a/archival/libunarchive/get_header_tar_lzma.c
+++ b/archival/libunarchive/get_header_tar_lzma.c
@@ -9,7 +9,7 @@
 #include "libbb.h"
 #include "unarchive.h"
 
-char FAST_FUNC get_header_tar_lzma(archive_handle_t * archive_handle)
+char FAST_FUNC get_header_tar_lzma(archive_handle_t *archive_handle)
 {
         /* Can't lseek over pipes */
         archive_handle->seek = seek_by_read;
diff --git a/archival/rpm.c b/archival/rpm.c
index 3d03dbcce..c4bcd605d 100644
--- a/archival/rpm.c
+++ b/archival/rpm.c
@@ -202,10 +202,9 @@ static void extract_cpio_gz(int fd)
         archive_handle->seek = seek_by_read;
         //archive_handle->action_header = header_list;
         archive_handle->action_data = data_extract_all;
-        archive_handle->flags |= ARCHIVE_PRESERVE_DATE;
-        archive_handle->flags |= ARCHIVE_CREATE_LEADING_DIRS;
+        archive_handle->ah_flags = ARCHIVE_PRESERVE_DATE | ARCHIVE_CREATE_LEADING_DIRS;
         archive_handle->src_fd = fd;
-        archive_handle->offset = 0;
+        /*archive_handle->offset = 0; - init_handle() did it */
 
         xread(archive_handle->src_fd, &magic, 2);
 #if BB_MMU
diff --git a/archival/tar.c b/archival/tar.c
index 2a140184c..526edb69d 100644
--- a/archival/tar.c
+++ b/archival/tar.c
@@ -814,9 +814,9 @@ int tar_main(int argc ATTRIBUTE_UNUSED, char **argv)
 
         /* Initialise default values */
         tar_handle = init_handle();
-        tar_handle->flags = ARCHIVE_CREATE_LEADING_DIRS
-                          | ARCHIVE_PRESERVE_DATE
-                          | ARCHIVE_EXTRACT_UNCONDITIONAL;
+        tar_handle->ah_flags = ARCHIVE_CREATE_LEADING_DIRS
+                             | ARCHIVE_PRESERVE_DATE
+                             | ARCHIVE_EXTRACT_UNCONDITIONAL;
 
         /* Prepend '-' to the first argument if required */
         opt_complementary = "--:" // first arg is options
@@ -862,13 +862,13 @@ int tar_main(int argc ATTRIBUTE_UNUSED, char **argv)
                 tar_handle->action_data = data_extract_to_stdout;
 
         if (opt & OPT_KEEP_OLD)
-                tar_handle->flags &= ~ARCHIVE_EXTRACT_UNCONDITIONAL;
+                tar_handle->ah_flags &= ~ARCHIVE_EXTRACT_UNCONDITIONAL;
 
         if (opt & OPT_NOPRESERVE_OWN)
-                tar_handle->flags |= ARCHIVE_NOPRESERVE_OWN;
+                tar_handle->ah_flags |= ARCHIVE_NOPRESERVE_OWN;
 
         if (opt & OPT_NOPRESERVE_PERM)
-                tar_handle->flags |= ARCHIVE_NOPRESERVE_PERM;
+                tar_handle->ah_flags |= ARCHIVE_NOPRESERVE_PERM;
 
         if (opt & OPT_GZIP)
                 get_header_ptr = get_header_tar_gz;
diff --git a/include/unarchive.h b/include/unarchive.h
index 721f879a4..1fab570c3 100644
--- a/include/unarchive.h
+++ b/include/unarchive.h
@@ -30,7 +30,7 @@ typedef struct file_header_t {
 } file_header_t;
 
 typedef struct archive_handle_t {
-        /* define if the header and data component should be processed */
+        /* Define if the header and data component should be processed */
         char FAST_FUNC (*filter)(struct archive_handle_t *);
         llist_t *accept;
         /* List of files that have been rejected */
@@ -41,10 +41,10 @@ typedef struct archive_handle_t {
         /* Contains the processed header entry */
         file_header_t *file_header;
 
-        /* process the header component, e.g. tar -t */
+        /* Process the header component, e.g. tar -t */
         void FAST_FUNC (*action_header)(const file_header_t *);
 
-        /* process the data component, e.g. extract to filesystem */
+        /* Process the data component, e.g. extract to filesystem */
         void FAST_FUNC (*action_data)(struct archive_handle_t *);
 
         /* How to process any sub archive, e.g. get_header_tar_gz */
@@ -66,7 +66,11 @@ typedef struct archive_handle_t {
         char *buffer;
 
         /* Flags and misc. stuff */
-        unsigned char flags;
+        unsigned char ah_flags;
+
+        /* "Private" storage for archivers */
+//      unsigned char ah_priv_inited;
+        void *ah_priv[8];
 
 } archive_handle_t;