| /* vi: set sw=4 ts=4: */ |
| /* |
| * Mini ar implementation for busybox |
| * |
| * Copyright (C) 2000 by Glenn McGrath |
| * Written by Glenn McGrath <bug1@optushome.com.au> 1 June 2000 |
| * |
| * Based in part on BusyBox tar, Debian dpkg-deb and GNU ar. |
| * |
| * 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 |
| * 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 |
| * |
| */ |
| #include <fcntl.h> |
| #include <string.h> |
| #include <stdlib.h> |
| #include <getopt.h> |
| #include <unistd.h> |
| #include "busybox.h" |
| |
| typedef struct ar_headers_s { |
| char *name; |
| off_t size; |
| uid_t uid; |
| gid_t gid; |
| mode_t mode; |
| time_t mtime; |
| off_t offset; |
| struct ar_headers_s *next; |
| } ar_headers_t; |
| |
| /* |
| * return the headerL_t struct for the filename descriptor |
| */ |
| extern ar_headers_t get_ar_headers(int srcFd) |
| { |
| typedef struct raw_ar_header_s { /* Byte Offset */ |
| char name[16]; /* 0-15 */ |
| char date[12]; /* 16-27 */ |
| char uid[6]; |
| char gid[6]; /* 28-39 */ |
| char mode[8]; /* 40-47 */ |
| char size[10]; /* 48-57 */ |
| char fmag[2]; /* 58-59 */ |
| } raw_ar_header_t; |
| |
| raw_ar_header_t raw_ar_header; |
| |
| ar_headers_t *head, *entry; |
| char ar_magic[8]; |
| char *long_name=NULL; |
| |
| head = (ar_headers_t *) xmalloc(sizeof(ar_headers_t)); |
| entry = (ar_headers_t *) xmalloc(sizeof(ar_headers_t)); |
| |
| /* check ar magic */ |
| if (full_read(srcFd, ar_magic, 8) != 8) { |
| error_msg_and_die("cannot read magic"); |
| } |
| |
| if (strncmp(ar_magic,"!<arch>",7) != 0) { |
| error_msg_and_die("invalid magic"); |
| } |
| |
| while (full_read(srcFd, (char *) &raw_ar_header, 60)==60) { |
| /* check the end of header markers are valid */ |
| if ((raw_ar_header.fmag[0]!='`') || (raw_ar_header.fmag[1]!='\n')) { |
| char newline; |
| if (raw_ar_header.fmag[1]!='`') { |
| break; |
| } |
| /* some version of ar, have an extra '\n' after each entry */ |
| read(srcFd, &newline, 1); |
| if (newline!='\n') { |
| break; |
| } |
| /* fix up the header, we started reading 1 byte too early due to a '\n' */ |
| memmove((char *) &raw_ar_header, (char *)&raw_ar_header+1, 59); |
| /* dont worry about adding the last '\n', we dont need it now */ |
| } |
| |
| entry->size = (off_t) atoi(raw_ar_header.size); |
| /* long filenames have '/' as the first character */ |
| if (raw_ar_header.name[0] == '/') { |
| if (raw_ar_header.name[1] == '/') { |
| /* multiple long filenames are stored as data in one entry */ |
| long_name = (char *) xrealloc(long_name, entry->size); |
| full_read(srcFd, long_name, entry->size); |
| continue; |
| } |
| else { |
| /* The number after the '/' indicates the offset in the ar data section |
| (saved in variable long_name) that conatains the real filename */ |
| const int long_name_offset = (int) atoi((char *) &raw_ar_header.name[1]); |
| entry->name = xmalloc(strlen(&long_name[long_name_offset])); |
| strcpy(entry->name, &long_name[long_name_offset]); |
| } |
| } |
| else { |
| /* short filenames */ |
| entry->name = xmalloc(16); |
| strncpy(entry->name, raw_ar_header.name, 16); |
| } |
| entry->name[strcspn(entry->name, " /")]='\0'; |
| |
| /* convert the rest of the now valid char header to its typed struct */ |
| parse_mode(raw_ar_header.mode, &entry->mode); |
| entry->mtime = atoi(raw_ar_header.date); |
| entry->uid = atoi(raw_ar_header.uid); |
| entry->gid = atoi(raw_ar_header.gid); |
| entry->offset = lseek(srcFd, 0, SEEK_CUR); |
| |
| /* add this entries header to our combined list */ |
| entry->next = (ar_headers_t *) xmalloc(sizeof(ar_headers_t)); |
| *entry->next = *head; |
| *head = *entry; |
| lseek(srcFd, (off_t) entry->size, SEEK_CUR); |
| } |
| return(*head); |
| } |
| |
| extern int ar_main(int argc, char **argv) |
| { |
| const int preserve_date = 1; /* preserve original dates */ |
| const int verbose = 2; /* be verbose */ |
| const int display = 4; /* display contents */ |
| const int extract_to_file = 8; /* extract contents of archive */ |
| const int extract_to_stdout = 16; /* extract to stdout */ |
| |
| int funct = 0, opt=0; |
| int srcFd=0, dstFd=0; |
| |
| ar_headers_t head, *extract_list=NULL; |
| |
| extract_list = (ar_headers_t *) xmalloc(sizeof(ar_headers_t)); |
| |
| while ((opt = getopt(argc, argv, "ovtpx")) != -1) { |
| switch (opt) { |
| case 'o': |
| funct |= preserve_date; |
| break; |
| case 'v': |
| funct |= verbose; |
| break; |
| case 't': |
| funct |= display; |
| break; |
| case 'p': |
| funct |= extract_to_stdout; |
| break; |
| case 'x': |
| funct |= extract_to_file; |
| break; |
| default: |
| show_usage(); |
| } |
| } |
| |
| /* check the src filename was specified */ |
| if (optind == argc) |
| show_usage(); |
| |
| if ( (srcFd = open(argv[optind], O_RDONLY)) < 0) |
| error_msg_and_die("Cannot read %s", argv[optind]); |
| |
| optind++; |
| head = get_ar_headers(srcFd); |
| |
| /* find files to extract or display */ |
| /* search through argv and build extract list */ |
| for (;optind<argc; optind++) { |
| ar_headers_t *ar_entry; |
| ar_entry = (ar_headers_t *) xmalloc(sizeof(ar_headers_t)); |
| ar_entry = &head; |
| while (ar_entry->next != NULL) { |
| if (strcmp(argv[optind], ar_entry->name) == 0) { |
| ar_headers_t *tmp; |
| tmp = (ar_headers_t *) xmalloc(sizeof(ar_headers_t)); |
| *tmp = *extract_list; |
| *extract_list = *ar_entry; |
| extract_list->next = tmp; |
| break; |
| } |
| ar_entry=ar_entry->next; |
| } |
| } |
| |
| /* if individual files not found extract all files */ |
| if (extract_list->next==NULL) { |
| extract_list = &head; |
| } |
| |
| /* find files to extract or display */ |
| while (extract_list->next != NULL) { |
| if (funct & extract_to_file) { |
| dstFd = open(extract_list->name, O_WRONLY | O_CREAT, extract_list->mode); |
| } |
| else if (funct & extract_to_stdout) { |
| dstFd = fileno(stdout); |
| } |
| if ((funct & extract_to_file) || (funct & extract_to_stdout)) { |
| lseek(srcFd, extract_list->offset, SEEK_SET); |
| copy_file_chunk(srcFd, dstFd, (off_t) extract_list->size); |
| } |
| if (funct & verbose) { |
| printf("%s %d/%d %8d %s ", mode_string(extract_list->mode), |
| extract_list->uid, extract_list->gid, |
| (int) extract_list->size, time_string(extract_list->mtime)); |
| } |
| if ((funct & display) || (funct & verbose)){ |
| printf("%s\n", extract_list->name); |
| } |
| extract_list=extract_list->next; |
| } |
| return EXIT_SUCCESS; |
| } |