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/*
* 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.
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "unarchive.h"
#include "libbb.h"
file_header_t *get_header_ar(FILE *src_stream)
{
file_header_t *typed;
union {
char raw[60];
struct {
char name[16];
char date[12];
char uid[6];
char gid[6];
char mode[8];
char size[10];
char magic[2];
} formated;
} ar;
static char *ar_long_names;
if (fread(ar.raw, 1, 60, src_stream) != 60) {
return(NULL);
}
archive_offset += 60;
/* align the headers based on the header magic */
if ((ar.formated.magic[0] != '`') || (ar.formated.magic[1] != '\n')) {
/* some version of ar, have an extra '\n' after each data entry,
* this puts the next header out by 1 */
if (ar.formated.magic[1] != '`') {
error_msg("Invalid magic");
return(NULL);
}
/* read the next char out of what would be the data section,
* if its a '\n' then it is a valid header offset by 1*/
archive_offset++;
if (fgetc(src_stream) != '\n') {
error_msg("Invalid magic");
return(NULL);
}
/* fix up the header, we started reading 1 byte too early */
/* raw_header[60] wont be '\n' as it should, but it doesnt matter */
memmove(ar.raw, &ar.raw[1], 59);
}
typed = (file_header_t *) xcalloc(1, sizeof(file_header_t));
typed->size = (size_t) atoi(ar.formated.size);
/* long filenames have '/' as the first character */
if (ar.formated.name[0] == '/') {
if (ar.formated.name[1] == '/') {
/* If the second char is a '/' then this entries data section
* stores long filename for multiple entries, they are stored
* in static variable long_names for use in future entries */
ar_long_names = (char *) xrealloc(ar_long_names, typed->size);
fread(ar_long_names, 1, typed->size, src_stream);
archive_offset += typed->size;
/* This ar entries data section only contained filenames for other records
* they are stored in the static ar_long_names for future reference */
return (get_header_ar(src_stream)); /* Return next header */
} else if (ar.formated.name[1] == ' ') {
/* This is the index of symbols in the file for compilers */
seek_sub_file(src_stream, typed->size);
return (get_header_ar(src_stream)); /* Return next header */
} else {
/* The number after the '/' indicates the offset in the ar data section
(saved in variable long_name) that conatains the real filename */
if (!ar_long_names) {
error_msg("Cannot resolve long file name");
return (NULL);
}
typed->name = xstrdup(ar_long_names + atoi(&ar.formated.name[1]));
}
} else {
/* short filenames */
typed->name = xcalloc(1, 16);
strncpy(typed->name, ar.formated.name, 16);
}
typed->name[strcspn(typed->name, " /")]='\0';
/* convert the rest of the now valid char header to its typed struct */
parse_mode(ar.formated.mode, &typed->mode);
typed->mtime = atoi(ar.formated.date);
typed->uid = atoi(ar.formated.uid);
typed->gid = atoi(ar.formated.gid);
return(typed);
}
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