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431a7c9c5

Denis Vlasenko
Denis Vlasenko
2008-02-19
FAILED Duration: 18s

Subject

tar: optional autodetection of gz/bz2 compressed tarballs. +130 bytes. Closes bug 992.

Binary

No binary (build failed)

Architecture & Compiler Flags

Architecture: x86_64-linux-gnu Compiler: gcc (Ubuntu 11.4.0-1ubuntu1~22.04.3) 11.4.0

—

Build Log

(log yok)

Commit Diff GitHub →

archival/Config.in +22 -14archival/libunarchive/get_header_tar.c +44 -8archival/tar.c +26 -9
archival/Config.in+22 -14
@@ -166,6 +166,14 @@ config FEATURE_TAR_CREATE
If you enable this option you'll be able to create
tar archives using the `-c' option.
+config FEATURE_TAR_GZIP
+ bool "Enable -z option"
+ default y
+ depends on TAR
+ help
+ If you enable this option tar will be able to call gzip,
+ when creating or extracting tar gziped archives.
+
config FEATURE_TAR_BZIP2
bool "Enable -j option to handle .tar.bz2 files"
default n
@@ -182,29 +190,29 @@ config FEATURE_TAR_LZMA
If you enable this option you'll be able to extract
archives compressed with lzma.
-config FEATURE_TAR_FROM
- bool "Enable -X (exclude from) and -T (include from) options)"
+config FEATURE_TAR_COMPRESS
+ bool "Enable -Z option"
default n
depends on TAR
help
- If you enable this option you'll be able to specify
- a list of files to include or exclude from an archive.
+ If you enable this option tar will be able to call uncompress,
+ when extracting .tar.Z archives.
-config FEATURE_TAR_GZIP
- bool "Enable -z option"
- default y
- depends on TAR
+config FEATURE_TAR_AUTODETECT
+ bool "Let tar autodetect gz/bz2 compresses tarballs"
+ default n
+ depends on FEATURE_TAR_GZIP || FEATURE_TAR_BZIP2
help
- If you enable this option tar will be able to call gzip,
- when creating or extracting tar gziped archives.
+ With this option tar can automatically detect gzip/bzip2 compressed
+ tarballs. Currently it works only on seekable streams.
-config FEATURE_TAR_COMPRESS
- bool "Enable -Z option"
+config FEATURE_TAR_FROM
+ bool "Enable -X (exclude from) and -T (include from) options)"
default n
depends on TAR
help
- If you enable this option tar will be able to call uncompress,
- when extracting .tar.Z archives.
+ If you enable this option you'll be able to specify
+ a list of files to include or exclude from an archive.
config FEATURE_TAR_OLDGNU_COMPATIBILITY
bool "Enable support for old tar header format"
archival/libunarchive/get_header_tar.c+44 -8
@@ -46,6 +46,9 @@ void BUG_tar_header_size(void);
char 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 {
@@ -115,7 +118,7 @@ char get_header_tar(archive_handle_t *archive_handle)
* Read until the end to empty the pipe from gz or bz2
*/
while (full_read(archive_handle->src_fd, &tar, 512) == 512)
- /* repeat */;
+ continue;
return EXIT_FAILURE;
}
end = 1;
@@ -123,16 +126,49 @@ char get_header_tar(archive_handle_t *archive_handle)
}
end = 0;
- /* Check header has valid magic, "ustar" is for the proper tar
- * 0's are for the old tar format
- */
- if (strncmp(tar.magic, "ustar", 5) != 0) {
-#if ENABLE_FEATURE_TAR_OLDGNU_COMPATIBILITY
- if (memcmp(tar.magic, "\0\0\0\0", 5) != 0)
+ /* Check header has valid magic, "ustar" is for the proper tar,
+ * five NULs are for the old tar format */
+ if (strncmp(tar.magic, "ustar", 5) != 0
+ && (!ENABLE_FEATURE_TAR_OLDGNU_COMPATIBILITY
+ || memcmp(tar.magic, "\0\0\0\0", 5) != 0)
+ ) {
+#if ENABLE_FEATURE_TAR_AUTODETECT
+ char (*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,
+ * we can switch to get_header_tar_gz/bz2/lzma().
+ * Needs seekable fd. I wish recv(MSG_PEEK) would work
+ * on any fd... */
+ if (not_first)
+ goto err;
+#if ENABLE_FEATURE_TAR_GZIP
+ if (tar.name[0] == 0x1f && tar.name[1] == 0x8b) { /* gzip */
+ get_header_ptr = get_header_tar_gz;
+ } else
#endif
- bb_error_msg_and_die("invalid tar magic");
+#if ENABLE_FEATURE_TAR_BZIP2
+ if (tar.name[0] == 'B' && tar.name[1] == 'Z'
+ && tar.name[2] == 'h' && isdigit(tar.name[3])
+ ) { /* bzip2 */
+ get_header_ptr = get_header_tar_bz2;
+ } else
+#endif
+ goto err;
+ if (lseek(archive_handle->src_fd, -512, SEEK_CUR) != 0)
+ goto err;
+ while (get_header_ptr(archive_handle) == EXIT_SUCCESS)
+ continue;
+ return EXIT_FAILURE;
+ err:
+#endif /* FEATURE_TAR_AUTODETECT */
+ 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
archival/tar.c+26 -9
@@ -33,8 +33,17 @@
#define FNM_LEADING_DIR 0
#endif
+
#define block_buf bb_common_bufsiz1
+
+#if !ENABLE_FEATURE_TAR_GZIP && !ENABLE_FEATURE_TAR_BZIP2
+/* Do not pass gzip flag to writeTarFile() */
+#define writeTarFile(tar_fd, verboseFlag, dereferenceFlag, include, exclude, gzip) \
+ writeTarFile(tar_fd, verboseFlag, dereferenceFlag, include, exclude)
+#endif
+
+
#if ENABLE_FEATURE_TAR_CREATE
/* Tar file constants */
@@ -514,18 +523,23 @@ static int writeTarFile(const int tar_fd, const int verboseFlag,
if (fstat(tbInfo.tarFd, &tbInfo.statBuf) < 0)
bb_perror_msg_and_die("cannot stat tar file");
- if ((ENABLE_FEATURE_TAR_GZIP || ENABLE_FEATURE_TAR_BZIP2) && gzip) {
-// On Linux, vfork never unpauses parent early, although standard
-// allows for that. Do we want to waste bytes checking for it?
+#if ENABLE_FEATURE_TAR_GZIP || ENABLE_FEATURE_TAR_BZIP2
+ if (gzip) {
+#if ENABLE_FEATURE_TAR_GZIP && ENABLE_FEATURE_TAR_BZIP2
+ const char *zip_exec = (gzip == 1) ? "gzip" : "bzip2";
+#elif ENABLE_FEATURE_TAR_GZIP
+ const char *zip_exec = "gzip";
+#else /* only ENABLE_FEATURE_TAR_BZIP2 */
+ const char *zip_exec = "bzip2";
+#endif
+ // On Linux, vfork never unpauses parent early, although standard
+ // allows for that. Do we want to waste bytes checking for it?
#define WAIT_FOR_CHILD 0
-
volatile int vfork_exec_errno = 0;
#if WAIT_FOR_CHILD
struct fd_pair gzipStatusPipe;
#endif
struct fd_pair gzipDataPipe;
- const char *zip_exec = (gzip == 1) ? "gzip" : "bzip2";
-
xpiped_pair(gzipDataPipe);
#if WAIT_FOR_CHILD
xpiped_pair(gzipStatusPipe);
@@ -584,6 +598,7 @@ static int writeTarFile(const int tar_fd, const int verboseFlag,
bb_perror_msg_and_die("cannot exec %s", zip_exec);
}
}
+#endif
tbInfo.excludeList = exclude;
@@ -934,11 +949,13 @@ int tar_main(int argc, char **argv)
/* create an archive */
if (opt & OPT_CREATE) {
+#if ENABLE_FEATURE_TAR_GZIP || ENABLE_FEATURE_TAR_BZIP2
int zipMode = 0;
- if (ENABLE_FEATURE_TAR_GZIP && get_header_ptr == get_header_tar_gz)
+ if (ENABLE_FEATURE_TAR_GZIP && (opt & OPT_GZIP))
zipMode = 1;
- if (ENABLE_FEATURE_TAR_BZIP2 && get_header_ptr == get_header_tar_bz2)
+ if (ENABLE_FEATURE_TAR_BZIP2 && (opt & OPT_BZIP2))
zipMode = 2;
+#endif
/* NB: writeTarFile() closes tar_handle->src_fd */
return writeTarFile(tar_handle->src_fd, verboseFlag, opt & OPT_DEREFERENCE,
tar_handle->accept,
@@ -946,7 +963,7 @@ int tar_main(int argc, char **argv)
}
while (get_header_ptr(tar_handle) == EXIT_SUCCESS)
- /* nothing */;
+ continue;
/* Check that every file that should have been extracted was */
while (tar_handle->accept) {