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Reorganized project structure in order to make functions testable

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root 2020-09-28 15:00:33 +00:00
parent 0625f30f7a
commit eef5b8bdeb
6 changed files with 207 additions and 360 deletions
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39
oss-internship-2020/sapi_libarchive/examples/CMakeLists.txt
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@ -12,38 +12,37 @@
# See the License for the specific language governing permissions and
# limitations under the License.
add_library(helpers STATIC
helpers.h
helpers.cc
add_library(sapi_minitar_lib STATIC
sapi_minitar.cc
sapi_minitar.h
)
target_link_libraries(helpers PUBLIC
sapi::sapi
sandbox2::fileops
sandbox2::util
sandbox2::file_base
sandbox2::executor
sandbox2::temp_file
glog::glog
libarchive_sapi
target_link_libraries(sapi_minitar_lib PUBLIC
libarchive_sapi
sapi::sapi
sandbox2::fileops
sandbox2::util
sandbox2::file_base
sandbox2::executor
sandbox2::temp_file
glog::glog
)
add_executable(sapi_minitar
sapi_minitar.cc
sapi_minitar_main.cc
)
target_link_libraries(sapi_minitar PRIVATE
helpers
libarchive_sapi
sapi::sapi
#glog::glog
#libarchive_sapi
#sapi::sapi
sapi_minitar_lib
#glog::glog
)
add_executable(minitar
orig/minitar.cc
orig/minitar.cc
)
target_link_libraries(minitar PRIVATE
archive
archive
)

36
oss-internship-2020/sapi_libarchive/examples/helpers.cc
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@ -1,36 +0,0 @@
#include "helpers.h"
std::string MakeAbsolutePathAtCWD(const std::string& path) {
std::string result = sandbox2::file_util::fileops::MakeAbsolute(
path, sandbox2::file_util::fileops::GetCWD());
CHECK(result != "") << "Could not create absolute path for: " << path;
return sandbox2::file::CleanPath(result);
}
std::vector<std::string> MakeAbsolutePathsVec(const char* argv[]) {
std::vector<std::string> arr;
sandbox2::util::CharPtrArrToVecString(const_cast<char* const*>(argv), &arr);
std::transform(arr.begin(), arr.end(), arr.begin(), MakeAbsolutePathAtCWD);
return arr;
}
std::string CheckStatusAndGetString(const absl::StatusOr<char*>& status,
LibarchiveSandbox& sandbox) {
CHECK(status.ok() && status.value() != NULL) << "Could not get error message";
absl::StatusOr<std::string> ret =
sandbox.GetCString(sapi::v::RemotePtr(status.value()));
CHECK(ret.ok()) << "Could not transfer error message";
return ret.value();
}
std::string CreateTempDirAtCWD() {
std::string cwd = sandbox2::file_util::fileops::GetCWD();
CHECK(!cwd.empty()) << "Could not get current working directory";
cwd.append("/");
absl::StatusOr<std::string> result = sandbox2::CreateTempDir(cwd);
CHECK(result.ok()) << "Could not create temporary directory at " << cwd;
return result.value();
}

23
oss-internship-2020/sapi_libarchive/examples/sandbox.h
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@ -2,14 +2,19 @@
#define SAPI_LIBARCHIVE_SANDBOX_H
#include <asm/unistd_64.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <syscall.h>
#include <unistd.h>
#include "helpers.h"
#include "libarchive_sapi.sapi.h"
#include "sapi_minitar.h"
// #include "sandboxed_api/sandbox2/util/fileops.h"
// When creating an archive, we need read permissions on each of the file/directory added
// in the archive. Also, in order to create the archive, we map /output with the basename of
// the archive. This way, the program can create the file without having access to anything else.
// When creating an archive, we need read permissions on each of the
// file/directory added in the archive. Also, in order to create the archive, we
// map /output with the basename of the archive. This way, the program can
// create the file without having access to anything else.
class SapiLibarchiveSandboxCreate : public LibarchiveSandbox {
public:
explicit SapiLibarchiveSandboxCreate(const std::vector<std::string>& files,
@ -67,11 +72,11 @@ class SapiLibarchiveSandboxCreate : public LibarchiveSandbox {
};
// When an archive is extracted, the generated files/directories will be placed
// relative to the current working directory. In order to add permissions to this
// we create a temporary directory at every extraction. Then, we change the directory of
// the sandboxed process to that directory and map it to the current "real" working
// directory. This way the contents of the archived will pe placed correctly without
// offering additional permission.
// relative to the current working directory. In order to add permissions to
// this we create a temporary directory at every extraction. Then, we change the
// directory of the sandboxed process to that directory and map it to the
// current "real" working directory. This way the contents of the archived will
// pe placed correctly without offering additional permission.
class SapiLibarchiveSandboxExtract : public LibarchiveSandbox {
public:
explicit SapiLibarchiveSandboxExtract(absl::string_view archive_path,

339
oss-internship-2020/sapi_libarchive/examples/sapi_minitar.cc
View File

@ -1,232 +1,7 @@
/*-
* This file is in the public domain.
* Do with it as you will.
*/
#include "sapi_minitar.h"
/*-
* This is a compact "tar" program whose primary goal is small size.
* Statically linked, it can be very small indeed. This serves a number
* of goals:
* o a testbed for libarchive (to check for link pollution),
* o a useful tool for space-constrained systems (boot floppies, etc),
* o a place to experiment with new implementation ideas for bsdtar,
* o a small program to demonstrate libarchive usage.
*
* Use the following macros to suppress features:
* NO_BZIP2 - Implies NO_BZIP2_CREATE and NO_BZIP2_EXTRACT
* NO_BZIP2_CREATE - Suppress bzip2 compression support.
* NO_BZIP2_EXTRACT - Suppress bzip2 auto-detection and decompression.
* NO_COMPRESS - Implies NO_COMPRESS_CREATE and NO_COMPRESS_EXTRACT
* NO_COMPRESS_CREATE - Suppress compress(1) compression support
* NO_COMPRESS_EXTRACT - Suppress compress(1) auto-detect and decompression.
* NO_CREATE - Suppress all archive creation support.
* NO_CPIO_EXTRACT - Suppress auto-detect and dearchiving of cpio archives.
* NO_GZIP - Implies NO_GZIP_CREATE and NO_GZIP_EXTRACT
* NO_GZIP_CREATE - Suppress gzip compression support.
* NO_GZIP_EXTRACT - Suppress gzip auto-detection and decompression.
* NO_LOOKUP - Try to avoid getpw/getgr routines, which can be very large
* NO_TAR_EXTRACT - Suppress tar extraction
*
* With all of the above macros defined (except NO_TAR_EXTRACT), you
* get a very small program that can recognize and extract essentially
* any uncompressed tar archive. On FreeBSD 5.1, this minimal program
* is under 64k, statically linked, which compares rather favorably to
* main(){printf("hello, world");}
* which is over 60k statically linked on the same operating system.
* Without any of the above macros, you get a static executable of
* about 180k with a lot of very sophisticated modern features.
* Obviously, it's trivial to add support for ISO, Zip, mtree,
* lzma/xz, etc. Just fill in the appropriate setup calls.
*/
// TODO general comments here
#include <archive.h>
#include <archive_entry.h>
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <unistd.h>
#include <cstdlib>
#include <iostream>
#include <memory>
#include "helpers.h"
#include "sandbox.h"
#include "sandboxed_api/sandbox2/util.h"
#include "sandboxed_api/sandbox2/util/path.h"
#include "sandboxed_api/var_array.h"
/*
* NO_CREATE implies NO_BZIP2_CREATE and NO_GZIP_CREATE and NO_COMPRESS_CREATE.
*/
#ifdef NO_CREATE
#undef NO_BZIP2_CREATE
#define NO_BZIP2_CREATE
#undef NO_COMPRESS_CREATE
#define NO_COMPRESS_CREATE
#undef NO_GZIP_CREATE
#define NO_GZIP_CREATE
#endif
/*
* The combination of NO_BZIP2_CREATE and NO_BZIP2_EXTRACT is
* equivalent to NO_BZIP2.
*/
#ifdef NO_BZIP2_CREATE
#ifdef NO_BZIP2_EXTRACT
#undef NO_BZIP2
#define NO_BZIP2
#endif
#endif
#ifdef NO_BZIP2
#undef NO_BZIP2_EXTRACT
#define NO_BZIP2_EXTRACT
#undef NO_BZIP2_CREATE
#define NO_BZIP2_CREATE
#endif
/*
* The combination of NO_COMPRESS_CREATE and NO_COMPRESS_EXTRACT is
* equivalent to NO_COMPRESS.
*/
#ifdef NO_COMPRESS_CREATE
#ifdef NO_COMPRESS_EXTRACT
#undef NO_COMPRESS
#define NO_COMPRESS
#endif
#endif
#ifdef NO_COMPRESS
#undef NO_COMPRESS_EXTRACT
#define NO_COMPRESS_EXTRACT
#undef NO_COMPRESS_CREATE
#define NO_COMPRESS_CREATE
#endif
/*
* The combination of NO_GZIP_CREATE and NO_GZIP_EXTRACT is
* equivalent to NO_GZIP.
*/
#ifdef NO_GZIP_CREATE
#ifdef NO_GZIP_EXTRACT
#undef NO_GZIP
#define NO_GZIP
#endif
#endif
#ifdef NO_GZIP
#undef NO_GZIP_EXTRACT
#define NO_GZIP_EXTRACT
#undef NO_GZIP_CREATE
#define NO_GZIP_CREATE
#endif
#ifndef NO_CREATE
static void create(const char* filename, int compress, const char** argv);
#endif
static void extract(const char* filename, int do_extract, int flags);
static int copy_data(sapi::v::RemotePtr* ar, sapi::v::RemotePtr* aw,
LibarchiveApi& api, SapiLibarchiveSandboxExtract& sandbox);
static void usage(void);
static int verbose = 0;
int main(int argc, const char** argv) {
google::InitGoogleLogging(argv[0]);
const char* filename = NULL;
int compress, flags, mode, opt;
(void)argc;
mode = 'x';
verbose = 0;
compress = '\0';
flags = ARCHIVE_EXTRACT_TIME;
/* Among other sins, getopt(3) pulls in printf(3). */
while (*++argv != NULL && **argv == '-') {
const char* p = *argv + 1;
while ((opt = *p++) != '\0') {
switch (opt) {
#ifndef NO_CREATE
case 'c':
mode = opt;
break;
#endif
case 'f':
if (*p != '\0')
filename = p;
else
filename = *++argv;
p += strlen(p);
break;
#ifndef NO_BZIP2_CREATE
case 'j':
compress = opt;
break;
#endif
case 'p':
flags |= ARCHIVE_EXTRACT_PERM;
flags |= ARCHIVE_EXTRACT_ACL;
flags |= ARCHIVE_EXTRACT_FFLAGS;
break;
case 't':
mode = opt;
break;
case 'v':
verbose++;
break;
case 'x':
mode = opt;
break;
#ifndef NO_BZIP2_CREATE
case 'y':
compress = opt;
break;
#endif
#ifndef NO_COMPRESS_CREATE
case 'Z':
compress = opt;
break;
#endif
#ifndef NO_GZIP_CREATE
case 'z':
compress = opt;
break;
#endif
default:
usage();
}
}
}
switch (mode) {
#ifndef NO_CREATE
case 'c':
create(filename, compress, argv);
break;
#endif
case 't':
extract(filename, 0, flags);
break;
case 'x':
extract(filename, 1, flags);
break;
}
return EXIT_SUCCESS;
}
#ifndef NO_CREATE
static void create(const char* initial_filename, int compress,
const char** argv) {
void create(const char* initial_filename, int compress, const char** argv,
int verbose /* = 1 */) {
// We split the filename path into dirname and filename. To the filename we
// prepend "/output/"" so that it will work with the security policy.
@ -236,11 +11,14 @@ static void create(const char* initial_filename, int compress,
std::string filename("/output/");
filename.append(filename_tmp);
std::vector<std::string> absolute_paths = MakeAbsolutePathsVec(argv);
std::vector<std::string> relative_paths;
std::vector<std::string> absolute_paths;
sandbox2::util::CharPtrArrToVecString(const_cast<char* const*>(argv),
&relative_paths);
&absolute_paths);
std::vector<std::string> relative_paths = absolute_paths;
std::transform(absolute_paths.begin(), absolute_paths.end(),
absolute_paths.begin(), MakeAbsolutePathAtCWD);
std::transform(relative_paths.begin(), relative_paths.end(),
relative_paths.begin(), sandbox2::file::CleanPath);
@ -264,7 +42,6 @@ static void create(const char* initial_filename, int compress,
absl::StatusOr<int> ret2;
switch (compress) {
#ifndef NO_BZIP2_CREATE
case 'j':
case 'y':
ret2 = api.archive_write_add_filter_bzip2(&a);
@ -272,23 +49,18 @@ static void create(const char* initial_filename, int compress,
CHECK(ret2.value() != ARCHIVE_FATAL)
<< "Unexpected result from write_add_filter_bzip2 call";
break;
#endif
#ifndef NO_COMPRESS_CREATE
case 'Z':
ret2 = api.archive_write_add_filter_compress(&a);
CHECK(ret2.ok()) << "write_add_filter_compress call failed";
CHECK(ret2.value() != ARCHIVE_FATAL)
<< "Unexpected result from write_add_filter_compress call";
break;
#endif
#ifndef NO_GZIP_CREATE
case 'z':
ret2 = api.archive_write_add_filter_gzip(&a);
CHECK(ret2.ok()) << "write_add_filter_gzip call failed";
CHECK(ret2.value() != ARCHIVE_FATAL)
<< "Unexpected result from write_add_filter_gzip call";
break;
#endif
default:
ret2 = api.archive_write_add_filter_none(&a);
CHECK(ret2.ok()) << "write_add_filter_none call failed";
@ -323,12 +95,11 @@ static void create(const char* initial_filename, int compress,
sapi::v::RemotePtr disk(ret.value());
#ifndef NO_LOOKUP
ret2 = api.archive_read_disk_set_standard_lookup(&disk);
CHECK(ret2.ok()) << "read_disk_set_standard_lookup call failed";
CHECK(ret2.value() != ARCHIVE_FATAL)
<< "Unexpected result from read_disk_set_standard_lookup call";
#endif
// We use the absolute path first.
ret2 = api.archive_read_disk_open(
&disk,
@ -413,9 +184,9 @@ static void create(const char* initial_filename, int compress,
CHECK(ret2.value() != ARCHIVE_FATAL)
<< "Unexpected result from write_header call";
// In the following section, the calls (read, archive_write_data) are done on
// the sandboxed process since we do not need to transfer the data in the client
// process.
// In the following section, the calls (read, archive_write_data) are done
// on the sandboxed process since we do not need to transfer the data in
// the client process.
if (ret2.value() > ARCHIVE_FAILED) {
int fd = open(CheckStatusAndGetString(
api.archive_entry_sourcepath(&entry), sandbox)
@ -428,7 +199,8 @@ static void create(const char* initial_filename, int compress,
sapi::v::Array<char> buff(kBuffSize);
sapi::v::UInt ssize(kBuffSize);
// We allocate the buffer remotely and then we can simply use the remote pointer.
// We allocate the buffer remotely and then we can simply use the remote
// pointer.
CHECK(sandbox.Allocate(&buff, true).ok())
<< "Could not allocate remote buffer";
@ -478,9 +250,9 @@ static void create(const char* initial_filename, int compress,
CHECK(ret2.ok()) << "write_free call failed";
CHECK(!ret2.value()) << "Unexpected result from write_free call";
}
#endif
static void extract(const char* filename, int do_extract, int flags) {
void extract(const char* filename, int do_extract, int flags,
int verbose /* = 1 */) {
std::string tmp_dir;
if (do_extract) {
tmp_dir = CreateTempDirAtCWD();
@ -528,42 +300,35 @@ static void extract(const char* filename, int do_extract, int flags) {
CHECK(ret2.value() != ARCHIVE_FATAL)
<< "Unexpected result from write_disk_set_options call";
#ifndef NO_BZIP2_EXTRACT
ret2 = api.archive_read_support_filter_bzip2(&a);
CHECK(ret2.ok()) << "read_support_filter_bzip2 call failed";
CHECK(ret2.value() != ARCHIVE_FATAL)
<< "Unexpected result from read_support_filter_bzip2 call";
#endif
#ifndef NO_GZIP_EXTRACT
ret2 = api.archive_read_support_filter_gzip(&a);
CHECK(ret2.ok()) << "read_suppport_filter_gzip call failed";
CHECK(ret2.value() != ARCHIVE_FATAL)
<< "Unexpected result from read_suppport_filter_gzip call";
#endif
#ifndef NO_COMPRESS_EXTRACT
ret2 = api.archive_read_support_filter_compress(&a);
CHECK(ret2.ok()) << "read_support_filter_compress call failed";
CHECK(ret2.value() != ARCHIVE_FATAL)
<< "Unexpected result from read_support_filter_compress call";
#endif
#ifndef NO_TAR_EXTRACT
ret2 = api.archive_read_support_format_tar(&a);
CHECK(ret2.ok()) << "read_support_format_tar call failed";
CHECK(ret2.value() != ARCHIVE_FATAL)
<< "Unexpected result fromread_support_format_tar call";
#endif
#ifndef NO_CPIO_EXTRACT
ret2 = api.archive_read_support_format_cpio(&a);
CHECK(ret2.ok()) << "read_support_format_cpio call failed";
CHECK(ret2.value() != ARCHIVE_FATAL)
<< "Unexpected result from read_support_format_tar call";
#endif
#ifndef NO_LOOKUP
ret2 = api.archive_write_disk_set_standard_lookup(&ext);
CHECK(ret2.ok()) << "write_disk_set_standard_lookup call failed";
CHECK(ret2.value() != ARCHIVE_FATAL)
<< "Unexpected result from write_disk_set_standard_lookup call";
#endif
const char* filename_ptr = filename_absolute.c_str();
if (filename_ptr != NULL && strcmp(filename_ptr, "-") == 0) {
@ -640,11 +405,10 @@ static void extract(const char* filename, int do_extract, int flags) {
CHECK(!ret2.value()) << "Unexpected result from write_free call";
}
// This function is only called from the "extract function". It is still isolated
// in order to not modify the code structure as much.
static int copy_data(sapi::v::RemotePtr* ar, sapi::v::RemotePtr* aw,
LibarchiveApi& api,
SapiLibarchiveSandboxExtract& sandbox) {
// This function is only called from the "extract function". It is still
// isolated in order to not modify the code structure as much.
int copy_data(sapi::v::RemotePtr* ar, sapi::v::RemotePtr* aw,
LibarchiveApi& api, SapiLibarchiveSandboxExtract& sandbox) {
absl::StatusOr<int> ret;
sapi::v::IntBase<struct archive_entry*> buff_ptr_tmp(0);
@ -680,28 +444,29 @@ static int copy_data(sapi::v::RemotePtr* ar, sapi::v::RemotePtr* aw,
}
}
static void usage(void) {
/* Many program options depend on compile options. */
const char* m =
"Usage: minitar [-"
#ifndef NO_CREATE
"c"
#endif
#ifndef NO_BZIP2
"j"
#endif
"tvx"
#ifndef NO_BZIP2
"y"
#endif
#ifndef NO_COMPRESS
"Z"
#endif
#ifndef NO_GZIP
"z"
#endif
"] [-f file] [file]\n";
std::cout << m << std::endl;
exit(EXIT_FAILURE);
std::string MakeAbsolutePathAtCWD(const std::string& path) {
std::string result = sandbox2::file_util::fileops::MakeAbsolute(
path, sandbox2::file_util::fileops::GetCWD());
CHECK(result != "") << "Could not create absolute path for: " << path;
return sandbox2::file::CleanPath(result);
}
std::string CheckStatusAndGetString(const absl::StatusOr<char*>& status,
LibarchiveSandbox& sandbox) {
CHECK(status.ok() && status.value() != NULL) << "Could not get error message";
absl::StatusOr<std::string> ret =
sandbox.GetCString(sapi::v::RemotePtr(status.value()));
CHECK(ret.ok()) << "Could not transfer error message";
return ret.value();
}
std::string CreateTempDirAtCWD() {
std::string cwd = sandbox2::file_util::fileops::GetCWD();
CHECK(!cwd.empty()) << "Could not get current working directory";
cwd.append("/");
absl::StatusOr<std::string> result = sandbox2::CreateTempDir(cwd);
CHECK(result.ok()) << "Could not create temporary directory at " << cwd;
return result.value();
}

34
oss-internship-2020/sapi_libarchive/examples/helpers.h → oss-internship-2020/sapi_libarchive/examples/sapi_minitar.h
View File

@ -1,22 +1,40 @@
#ifndef SAPI_LIBARCHIVE_HELPERS_H
#define SAPI_LIBARCHIVE_HELPERS_H
#ifndef SAPI_LIBARCHIVE_MINITAR_H
#define SAPI_LIBARCHIVE_MINITAR_H
#include <archive.h>
#include <archive_entry.h>
#include <fcntl.h>
#include <glog/logging.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <unistd.h>
#include <cstdlib>
#include <iostream>
#include <memory>
#include "libarchive_sapi.sapi.h"
#include "sandbox.h"
#include "sandboxed_api/sandbox2/util.h"
#include "sandboxed_api/sandbox2/util/fileops.h"
#include "sandboxed_api/sandbox2/util/path.h"
#include "sandboxed_api/sandbox2/util/temp_file.h"
#include "sandboxed_api/var_array.h"
void create(const char* filename, int compress, const char** argv,
int verbose = 1);
void extract(const char* filename, int do_extract, int flags, int verbose = 1);
int copy_data(sapi::v::RemotePtr* ar, sapi::v::RemotePtr* aw,
LibarchiveApi& api, SapiLibarchiveSandboxExtract& sandbox);
inline constexpr size_t kBlockSize = 10240;
inline constexpr size_t kBuffSize = 16384;
// Used to convert the paths provided as arguments for the program
// (the paths used) to an array of absolute paths. This allows the user
// to use either relative or absolute paths
std::vector<std::string> MakeAbsolutePathsVec(const char* argv[]);
// Converts only one string to an absolute path by prepending the current
// working directory to the relative path
std::string MakeAbsolutePathAtCWD(const std::string& path);
@ -32,4 +50,4 @@ std::string CheckStatusAndGetString(const absl::StatusOr<char*>& status,
// changes the current working directory to this temporary directory.
std::string CreateTempDirAtCWD();
#endif // SAPI_LIBARCHIVE_HELPERS_H
#endif // SAPI_LIBARCHIVE_MINITAR_H

96
oss-internship-2020/sapi_libarchive/examples/sapi_minitar_main.cc Normal file
View File

@ -0,0 +1,96 @@
#include <iostream>
#include "sapi_minitar.h"
static void usage(void);
int main(int argc, const char** argv) {
google::InitGoogleLogging(argv[0]);
const char* filename = NULL;
int compress, flags, mode, opt;
(void)argc;
mode = 'x';
int verbose = 0;
compress = '\0';
flags = ARCHIVE_EXTRACT_TIME;
while (*++argv != NULL && **argv == '-') {
const char* p = *argv + 1;
while ((opt = *p++) != '\0') {
switch (opt) {
case 'c':
mode = opt;
break;
case 'f':
if (*p != '\0')
filename = p;
else
filename = *++argv;
p += strlen(p);
break;
case 'j':
compress = opt;
break;
case 'p':
flags |= ARCHIVE_EXTRACT_PERM;
flags |= ARCHIVE_EXTRACT_ACL;
flags |= ARCHIVE_EXTRACT_FFLAGS;
break;
case 't':
mode = opt;
break;
case 'v':
verbose++;
break;
case 'x':
mode = opt;
break;
case 'y':
compress = opt;
break;
case 'Z':
compress = opt;
break;
case 'z':
compress = opt;
break;
default:
usage();
}
}
}
switch (mode) {
case 'c':
create(filename, compress, argv, verbose);
break;
case 't':
extract(filename, 0, flags, verbose);
break;
case 'x':
extract(filename, 1, flags, verbose);
break;
}
return EXIT_SUCCESS;
}
static void usage(void) {
/* Many program options depend on compile options. */
const char* m =
"Usage: minitar [-"
"c"
"j"
"tvx"
"y"
"Z"
"z"
"] [-f file] [file]\n";
std::cout << m << std::endl;
exit(EXIT_FAILURE);
}