diff options
| -rw-r--r-- | libbb/untar.c | 200 |
1 files changed, 200 insertions, 0 deletions
diff --git a/libbb/untar.c b/libbb/untar.c new file mode 100644 index 0000000..1542e39 --- /dev/null +++ b/libbb/untar.c @@ -0,0 +1,200 @@ +/* + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU Library General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. + * + * NOTE: This is used by deb_extract to avoid calling the whole tar applet. + * Its functionality should be merged with tar to avoid duplication + */ + +#include <stdlib.h> +#include <string.h> +#include <unistd.h> +#include "libbb.h" + +extern int untar(FILE *src_tar_file, int untar_function, char *base_path) +{ + typedef struct raw_tar_header { + char name[100]; /* 0-99 */ + char mode[8]; /* 100-107 */ + char uid[8]; /* 108-115 */ + char gid[8]; /* 116-123 */ + char size[12]; /* 124-135 */ + char mtime[12]; /* 136-147 */ + char chksum[8]; /* 148-155 */ + char typeflag; /* 156-156 */ + char linkname[100]; /* 157-256 */ + char magic[6]; /* 257-262 */ + char version[2]; /* 263-264 */ + char uname[32]; /* 265-296 */ + char gname[32]; /* 297-328 */ + char devmajor[8]; /* 329-336 */ + char devminor[8]; /* 337-344 */ + char prefix[155]; /* 345-499 */ + char padding[12]; /* 500-512 */ + } raw_tar_header_t; + +// const int dpkg_deb_contents = 1; +// const int dpkg_deb_control = 2; +// const int dpkg_deb_info = 4; + const int untar_extract = 8; +// const int dpkg_deb_verbose_extract = 16; +// const int dpkg_deb_list = 32; + + raw_tar_header_t raw_tar_header; + unsigned char *temp = (unsigned char *) &raw_tar_header; + long i; + long next_header_offset = 0; + long uncompressed_count = 0; + size_t size; + mode_t mode; + +// signal(SIGCHLD, child_died); + + while (fread((char *) &raw_tar_header, 1, 512, src_tar_file)==512) { + long sum = 0; + char *dir; + + uncompressed_count += 512; + + /* Check header has valid magic */ + if (strncmp(raw_tar_header.magic, "ustar", 5) != 0) { + /* Put this pack after TODO (check child still alive) is done */ +// error_msg("Invalid tar magic"); + break; + } + + /* Do checksum on headers */ + for (i = 0; i < 148 ; i++) { + sum += temp[i]; + } + sum += ' ' * 8; + for (i = 156; i < 512 ; i++) { + sum += temp[i]; + } + if (sum != strtol(raw_tar_header.chksum, NULL, 8)) { + error_msg("Invalid tar header checksum"); + break; + } + + /* convert to type'ed variables */ + size = strtol(raw_tar_header.size, NULL, 8); + parse_mode(raw_tar_header.mode, &mode); + + /* start of next header is at */ + next_header_offset = uncompressed_count + size; + if (size % 512 != 0) { + next_header_offset += (512 - size % 512); + } + + /* + * seek to start of control file, return length + * + if (dpkg_untar_function & dpkg_untar_seek_control) { + if ((raw_tar_header.typeflag == '0') || (raw_tar_header.typeflag == '\0')) { + char *tar_filename; + + tar_filename = strrchr(raw_tar_header.name, '/'); + if (tar_filename == NULL) { + tar_filename = strdup(raw_tar_header.name); + } else { + tar_filename++; + } + + if (strcmp(tar_filename, "control") == 0) { + return(size); + } + } + + } +*/ + /* extract files */ + dir = xmalloc(strlen(raw_tar_header.name) + strlen(base_path) + 2); + + sprintf(dir, "%s/%s", base_path, raw_tar_header.name); + create_path(dir, 0777); + switch (raw_tar_header.typeflag ) { + case '0': + case '\0': + /* If the name ends in a '/' then assume it is + * supposed to be a directory, and fall through + */ + if (raw_tar_header.name[strlen(raw_tar_header.name)-1] != '/') { + if (untar_function & untar_extract) { + int out_count=0; + FILE *dst_file; + + dst_file = wfopen(dir, "w"); + if (copy_file_chunk(src_tar_file, dst_file, size) == FALSE) { + error_msg_and_die("Couldnt extract file"); + } + uncompressed_count += out_count; + fclose(dst_file); + break; + } + } + case '5': + if (untar_function & untar_extract) { + if (create_path(dir, mode) != TRUE) { + free(dir); + perror_msg("%s: Cannot mkdir", raw_tar_header.name); + return(EXIT_FAILURE); + } + } + break; + case '1': + if (untar_function & untar_extract) { + if (link(raw_tar_header.linkname, raw_tar_header.name) < 0) { + free(dir); + perror_msg("%s: Cannot create hard link to '%s'", raw_tar_header.name, raw_tar_header.linkname); + return(EXIT_FAILURE); + } + } + break; + case '2': + if (untar_function & untar_extract) { + if (symlink(raw_tar_header.linkname, raw_tar_header.name) < 0) { + free(dir); + perror_msg("%s: Cannot create symlink to '%s'", raw_tar_header.name, raw_tar_header.linkname); + return(EXIT_FAILURE); + } + } + break; + case '3': + case '4': + case '6': +// if (tarExtractSpecial( &header, extractFlag, tostdoutFlag)==FALSE) +// errorFlag=TRUE; +// break; + default: + error_msg("Unknown file type '%c' in tar file", raw_tar_header.typeflag); + free(dir); + return(EXIT_FAILURE); + } + free(dir); + } + /* skip to start of next header */ + while(uncompressed_count < next_header_offset) { + char ch[2]; + if (fread(ch, 1, 1, src_tar_file) != 1) { + error_msg("read error\n"); + getchar(); + } else { + uncompressed_count++; + } + } + /* + * TODO: Check that gunzip child hasnt finished + */ + return(EXIT_SUCCESS); +} |