mirror of
https://github.com/sheumann/hush.git
synced 2024-08-27 03:29:05 +00:00
145 lines
4.4 KiB
C
145 lines
4.4 KiB
C
/* vi: set sw=4 ts=4: */
|
|
/* Copyright 2001 Glenn McGrath.
|
|
*
|
|
* Licensed under GPLv2 or later, see file LICENSE in this source tree.
|
|
*/
|
|
|
|
#include "libbb.h"
|
|
#include "bb_archive.h"
|
|
#include "ar.h"
|
|
|
|
/* WARNING: Clobbers str[len], so fields must be read in reverse order! */
|
|
static unsigned read_num(char *str, int base, int len)
|
|
{
|
|
int err;
|
|
|
|
/* ar fields are fixed length text strings (padded with spaces).
|
|
* Ensure bb_strtou doesn't read past the field in case the full
|
|
* width is used. */
|
|
str[len] = 0;
|
|
|
|
/* This code works because
|
|
* on misformatted numbers bb_strtou returns all-ones */
|
|
err = bb_strtou(str, NULL, base);
|
|
if (err == -1)
|
|
bb_error_msg_and_die("invalid ar header");
|
|
return err;
|
|
}
|
|
|
|
char FAST_FUNC get_header_ar(archive_handle_t *archive_handle)
|
|
{
|
|
file_header_t *typed = archive_handle->file_header;
|
|
unsigned size;
|
|
union {
|
|
char raw[60];
|
|
struct ar_header formatted;
|
|
} ar;
|
|
#if ENABLE_FEATURE_AR_LONG_FILENAMES
|
|
static char *ar_long_names;
|
|
static unsigned ar_long_name_size;
|
|
#endif
|
|
|
|
/* dont use xread as we want to handle the error ourself */
|
|
if (read(archive_handle->src_fd, ar.raw, 60) != 60) {
|
|
/* End Of File */
|
|
return EXIT_FAILURE;
|
|
}
|
|
|
|
/* ar header starts on an even byte (2 byte aligned)
|
|
* '\n' is used for padding
|
|
*/
|
|
if (ar.raw[0] == '\n') {
|
|
/* fix up the header, we started reading 1 byte too early */
|
|
memmove(ar.raw, &ar.raw[1], 59);
|
|
ar.raw[59] = xread_char(archive_handle->src_fd);
|
|
archive_handle->offset++;
|
|
}
|
|
archive_handle->offset += 60;
|
|
|
|
if (ar.formatted.magic[0] != '`' || ar.formatted.magic[1] != '\n')
|
|
bb_error_msg_and_die("invalid ar header");
|
|
|
|
/*
|
|
* Note that the fields MUST be read in reverse order as
|
|
* read_num() clobbers the next byte after the field!
|
|
* Order is: name, date, uid, gid, mode, size, magic.
|
|
*/
|
|
typed->size = size = read_num(ar.formatted.size, 10,
|
|
sizeof(ar.formatted.size));
|
|
|
|
/* special filenames have '/' as the first character */
|
|
if (ar.formatted.name[0] == '/') {
|
|
if (ar.formatted.name[1] == ' ') {
|
|
/* This is the index of symbols in the file for compilers */
|
|
data_skip(archive_handle);
|
|
archive_handle->offset += size;
|
|
return get_header_ar(archive_handle); /* Return next header */
|
|
}
|
|
#if ENABLE_FEATURE_AR_LONG_FILENAMES
|
|
if (ar.formatted.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_name_size = size;
|
|
free(ar_long_names);
|
|
ar_long_names = xmalloc(size);
|
|
xread(archive_handle->src_fd, ar_long_names, size);
|
|
archive_handle->offset += size;
|
|
/* Return next header */
|
|
return get_header_ar(archive_handle);
|
|
}
|
|
#else
|
|
bb_error_msg_and_die("long filenames not supported");
|
|
#endif
|
|
}
|
|
/* Only size is always present, the rest may be missing in
|
|
* long filename pseudo file. Thus we decode the rest
|
|
* after dealing with long filename pseudo file.
|
|
*/
|
|
typed->mode = read_num(ar.formatted.mode, 8, sizeof(ar.formatted.mode));
|
|
typed->gid = read_num(ar.formatted.gid, 10, sizeof(ar.formatted.gid));
|
|
typed->uid = read_num(ar.formatted.uid, 10, sizeof(ar.formatted.uid));
|
|
typed->mtime = read_num(ar.formatted.date, 10, sizeof(ar.formatted.date));
|
|
|
|
#if ENABLE_FEATURE_AR_LONG_FILENAMES
|
|
if (ar.formatted.name[0] == '/') {
|
|
unsigned long_offset;
|
|
|
|
/* The number after the '/' indicates the offset in the ar data section
|
|
* (saved in ar_long_names) that conatains the real filename */
|
|
long_offset = read_num(&ar.formatted.name[1], 10,
|
|
sizeof(ar.formatted.name) - 1);
|
|
if (long_offset >= ar_long_name_size) {
|
|
bb_error_msg_and_die("can't resolve long filename");
|
|
}
|
|
typed->name = xstrdup(ar_long_names + long_offset);
|
|
} else
|
|
#endif
|
|
{
|
|
/* short filenames */
|
|
typed->name = xstrndup(ar.formatted.name, 16);
|
|
}
|
|
|
|
typed->name[strcspn(typed->name, " /")] = '\0';
|
|
|
|
if (archive_handle->filter(archive_handle) == EXIT_SUCCESS) {
|
|
archive_handle->action_header(typed);
|
|
#if ENABLE_DPKG || ENABLE_DPKG_DEB
|
|
if (archive_handle->dpkg__sub_archive) {
|
|
while (archive_handle->dpkg__action_data_subarchive(archive_handle->dpkg__sub_archive) == EXIT_SUCCESS)
|
|
continue;
|
|
} else
|
|
#endif
|
|
archive_handle->action_data(archive_handle);
|
|
} else {
|
|
data_skip(archive_handle);
|
|
}
|
|
|
|
archive_handle->offset += typed->size;
|
|
/* Set the file pointer to the correct spot, we may have been reading a compressed file */
|
|
lseek(archive_handle->src_fd, archive_handle->offset, SEEK_SET);
|
|
|
|
return EXIT_SUCCESS;
|
|
}
|