sandboxed-api/oss-internship-2020/libarchive/ld_preload_example/minitar.cc

313 lines
7.0 KiB
C++
Raw Normal View History

2020-10-08 18:58:21 +08:00
// Copyright 2020 Google LLC
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
2020-10-09 21:52:17 +08:00
// clang-format off
2020-10-08 18:58:21 +08:00
#include "minitar.h" // NOLINT(build/include)
/*
* 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
void create(const char* filename, int compress, const char** argv);
#endif
void errmsg(const char*);
void extract(const char* filename, int do_extract, int flags);
int copy_data(struct archive*, struct archive*);
void msg(const char*);
void usage(void);
#ifndef NO_CREATE
void create(const char* filename, int compress, const char** argv,
int verbose) {
struct archive* a;
struct archive_entry* entry;
ssize_t len;
int fd;
a = archive_write_new();
switch (compress) {
#ifndef NO_BZIP2_CREATE
case 'j':
case 'y':
archive_write_add_filter_bzip2(a);
break;
#endif
#ifndef NO_COMPRESS_CREATE
case 'Z':
archive_write_add_filter_compress(a);
break;
#endif
#ifndef NO_GZIP_CREATE
case 'z':
archive_write_add_filter_gzip(a);
break;
#endif
default:
archive_write_add_filter_none(a);
break;
}
archive_write_set_format_ustar(a);
if (filename != NULL && strcmp(filename, "-") == 0) filename = NULL;
archive_write_open_filename(a, filename);
while (*argv != NULL) {
struct archive* disk = archive_read_disk_new();
#ifndef NO_LOOKUP
archive_read_disk_set_standard_lookup(disk);
#endif
int r;
r = archive_read_disk_open(disk, *argv);
if (r != ARCHIVE_OK) {
errmsg(archive_error_string(disk));
errmsg("\n");
exit(1);
}
for (;;) {
int needcr = 0;
entry = archive_entry_new();
r = archive_read_next_header2(disk, entry);
if (r == ARCHIVE_EOF) break;
if (r != ARCHIVE_OK) {
errmsg(archive_error_string(disk));
errmsg("\n");
exit(1);
}
archive_read_disk_descend(disk);
if (verbose) {
msg("a ");
msg(archive_entry_pathname(entry));
needcr = 1;
}
r = archive_write_header(a, entry);
if (r < ARCHIVE_OK) {
errmsg(": ");
errmsg(archive_error_string(a));
needcr = 1;
}
if (r == ARCHIVE_FATAL) exit(1);
if (r > ARCHIVE_FAILED) {
static char buff[16384];
fd = open(archive_entry_sourcepath(entry), O_RDONLY);
len = read(fd, buff, sizeof(buff));
while (len > 0) {
archive_write_data(a, buff, len);
len = read(fd, buff, sizeof(buff));
}
close(fd);
}
archive_entry_free(entry);
if (needcr) msg("\n");
}
archive_read_close(disk);
archive_read_free(disk);
argv++;
}
archive_write_close(a);
archive_write_free(a);
}
#endif
void extract(const char* filename, int do_extract, int flags, int verbose) {
struct archive* a;
struct archive* ext;
struct archive_entry* entry;
int r;
a = archive_read_new();
ext = archive_write_disk_new();
archive_write_disk_set_options(ext, flags);
#ifndef NO_BZIP2_EXTRACT
archive_read_support_filter_bzip2(a);
#endif
#ifndef NO_GZIP_EXTRACT
archive_read_support_filter_gzip(a);
#endif
#ifndef NO_COMPRESS_EXTRACT
archive_read_support_filter_compress(a);
#endif
#ifndef NO_TAR_EXTRACT
archive_read_support_format_tar(a);
#endif
#ifndef NO_CPIO_EXTRACT
archive_read_support_format_cpio(a);
#endif
#ifndef NO_LOOKUP
archive_write_disk_set_standard_lookup(ext);
#endif
if (filename != NULL && strcmp(filename, "-") == 0) filename = NULL;
if ((r = archive_read_open_filename(a, filename, 10240))) {
errmsg(archive_error_string(a));
errmsg("\n");
exit(r);
}
for (;;) {
int needcr = 0;
r = archive_read_next_header(a, &entry);
if (r == ARCHIVE_EOF) break;
if (r != ARCHIVE_OK) {
errmsg(archive_error_string(a));
errmsg("\n");
exit(1);
}
if (verbose && do_extract) msg("x ");
if (verbose || !do_extract) {
std::cout << archive_entry_pathname(entry) << std::endl;
msg(" ");
needcr = 1;
}
if (do_extract) {
r = archive_write_header(ext, entry);
if (r != ARCHIVE_OK) {
errmsg(archive_error_string(a));
needcr = 1;
} else {
r = copy_data(a, ext);
if (r != ARCHIVE_OK) needcr = 1;
}
}
if (needcr) msg("\n");
}
archive_read_close(a);
archive_read_free(a);
archive_write_close(ext);
archive_write_free(ext);
}
int copy_data(struct archive* ar, struct archive* aw) {
int r;
const void* buff;
size_t size;
int64_t offset;
for (;;) {
r = archive_read_data_block(ar, &buff, &size, &offset);
if (r == ARCHIVE_EOF) return (ARCHIVE_OK);
if (r != ARCHIVE_OK) {
errmsg(archive_error_string(ar));
return (r);
}
r = archive_write_data_block(aw, buff, size, offset);
if (r != ARCHIVE_OK) {
errmsg(archive_error_string(ar));
return (r);
}
}
}
void msg(const char* m) { write(1, m, strlen(m)); }
void errmsg(const char* m) {
if (m == NULL) {
m = "Error: No error description provided.\n";
}
write(2, m, strlen(m));
}
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";
errmsg(m);
exit(1);
}
2020-10-09 21:52:17 +08:00
// clang-format on