hush/coreutils/uudecode.c
Denys Vlasenko 2b48c38be6 uudecode: tolerate text input with CR+LF line ends
function                                             old     new   delta
read_stduu                                           265     308     +43
uudecode_main                                        313     317      +4

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2015-10-05 15:10:44 +02:00

251 lines
6.3 KiB
C

/* vi: set sw=4 ts=4: */
/*
* Copyright 2003, Glenn McGrath
*
* Licensed under GPLv2 or later, see file LICENSE in this source tree.
*
* Based on specification from
* http://www.opengroup.org/onlinepubs/007904975/utilities/uuencode.html
*
* Bugs: the spec doesn't mention anything about "`\n`\n" prior to the
* "end" line
*/
//usage:#define uudecode_trivial_usage
//usage: "[-o OUTFILE] [INFILE]"
//usage:#define uudecode_full_usage "\n\n"
//usage: "Uudecode a file\n"
//usage: "Finds OUTFILE in uuencoded source unless -o is given"
//usage:
//usage:#define uudecode_example_usage
//usage: "$ uudecode -o busybox busybox.uu\n"
//usage: "$ ls -l busybox\n"
//usage: "-rwxr-xr-x 1 ams ams 245264 Jun 7 21:35 busybox\n"
#include "libbb.h"
#if ENABLE_UUDECODE
static void FAST_FUNC read_stduu(FILE *src_stream, FILE *dst_stream, int flags UNUSED_PARAM)
{
char *line;
for (;;) {
int encoded_len, str_len;
char *line_ptr, *dst;
size_t line_len;
line_len = 64 * 1024;
line = xmalloc_fgets_str_len(src_stream, "\n", &line_len);
if (!line)
break;
/* Handle both Unix and MSDOS text, and stray trailing spaces */
str_len = line_len;
while (--str_len >= 0 && isspace(line[str_len]))
line[str_len] = '\0';
if (strcmp(line, "end") == 0) {
return; /* the only non-error exit */
}
line_ptr = line;
while (*line_ptr) {
*line_ptr = (*line_ptr - 0x20) & 0x3f;
line_ptr++;
}
str_len = line_ptr - line;
encoded_len = line[0] * 4 / 3;
/* Check that line is not too short. (we tolerate
* overly _long_ line to accommodate possible extra '`').
* Empty line case is also caught here. */
if (str_len <= encoded_len) {
break; /* go to bb_error_msg_and_die("short file"); */
}
if (encoded_len <= 0) {
/* Ignore the "`\n" line, why is it even in the encode file ? */
free(line);
continue;
}
if (encoded_len > 60) {
bb_error_msg_and_die("line too long");
}
dst = line;
line_ptr = line + 1;
do {
/* Merge four 6 bit chars to three 8 bit chars */
*dst++ = line_ptr[0] << 2 | line_ptr[1] >> 4;
encoded_len--;
if (encoded_len == 0) {
break;
}
*dst++ = line_ptr[1] << 4 | line_ptr[2] >> 2;
encoded_len--;
if (encoded_len == 0) {
break;
}
*dst++ = line_ptr[2] << 6 | line_ptr[3];
line_ptr += 4;
encoded_len -= 2;
} while (encoded_len > 0);
fwrite(line, 1, dst - line, dst_stream);
free(line);
}
bb_error_msg_and_die("short file");
}
#endif
#if ENABLE_UUDECODE
int uudecode_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int uudecode_main(int argc UNUSED_PARAM, char **argv)
{
FILE *src_stream;
char *outname = NULL;
char *line;
opt_complementary = "?1"; /* 1 argument max */
getopt32(argv, "o:", &outname);
argv += optind;
if (!argv[0])
*--argv = (char*)"-";
src_stream = xfopen_stdin(argv[0]);
/* Search for the start of the encoding */
while ((line = xmalloc_fgetline(src_stream)) != NULL) {
void FAST_FUNC (*decode_fn_ptr)(FILE *src, FILE *dst, int flags);
char *line_ptr;
FILE *dst_stream;
int mode;
if (is_prefixed_with(line, "begin-base64 ")) {
line_ptr = line + 13;
decode_fn_ptr = read_base64;
} else if (is_prefixed_with(line, "begin ")) {
line_ptr = line + 6;
decode_fn_ptr = read_stduu;
} else {
free(line);
continue;
}
/* begin line found. decode and exit */
mode = bb_strtou(line_ptr, NULL, 8);
if (outname == NULL) {
outname = strchr(line_ptr, ' ');
if (!outname)
break;
outname++;
trim(outname); /* remove trailing space (and '\r' for DOS text) */
if (!outname[0])
break;
}
dst_stream = stdout;
if (NOT_LONE_DASH(outname)) {
dst_stream = xfopen_for_write(outname);
fchmod(fileno(dst_stream), mode & (S_IRWXU | S_IRWXG | S_IRWXO));
}
free(line);
decode_fn_ptr(src_stream, dst_stream, /*flags:*/ BASE64_FLAG_UU_STOP + BASE64_FLAG_NO_STOP_CHAR);
/* fclose_if_not_stdin(src_stream); - redundant */
return EXIT_SUCCESS;
}
bb_error_msg_and_die("no 'begin' line");
}
#endif
//applet:IF_BASE64(APPLET(base64, BB_DIR_BIN, BB_SUID_DROP))
//kbuild:lib-$(CONFIG_BASE64) += uudecode.o
//config:config BASE64
//config: bool "base64"
//config: default y
//config: help
//config: Base64 encode and decode
//usage:#define base64_trivial_usage
//usage: "[-d] [FILE]"
//usage:#define base64_full_usage "\n\n"
//usage: "Base64 encode or decode FILE to standard output"
//usage: "\n -d Decode data"
////usage: "\n -w COL Wrap lines at COL (default 76, 0 disables)"
////usage: "\n -i When decoding, ignore non-alphabet characters"
#if ENABLE_BASE64
int base64_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int base64_main(int argc UNUSED_PARAM, char **argv)
{
FILE *src_stream;
unsigned opts;
opt_complementary = "?1"; /* 1 argument max */
opts = getopt32(argv, "d");
argv += optind;
if (!argv[0])
*--argv = (char*)"-";
src_stream = xfopen_stdin(argv[0]);
if (opts) {
read_base64(src_stream, stdout, /*flags:*/ (char)EOF);
} else {
enum {
SRC_BUF_SIZE = 76/4*3, /* This *MUST* be a multiple of 3 */
DST_BUF_SIZE = 4 * ((SRC_BUF_SIZE + 2) / 3),
};
char src_buf[SRC_BUF_SIZE];
char dst_buf[DST_BUF_SIZE + 1];
int src_fd = fileno(src_stream);
while (1) {
size_t size = full_read(src_fd, src_buf, SRC_BUF_SIZE);
if (!size)
break;
if ((ssize_t)size < 0)
bb_perror_msg_and_die(bb_msg_read_error);
/* Encode the buffer we just read in */
bb_uuencode(dst_buf, src_buf, size, bb_uuenc_tbl_base64);
xwrite(STDOUT_FILENO, dst_buf, 4 * ((size + 2) / 3));
bb_putchar('\n');
fflush(stdout);
}
}
fflush_stdout_and_exit(EXIT_SUCCESS);
}
#endif
/* Test script.
Put this into an empty dir with busybox binary, an run.
#!/bin/sh
test -x busybox || { echo "No ./busybox?"; exit; }
ln -sf busybox uudecode
ln -sf busybox uuencode
>A_null
echo -n A >A
echo -n AB >AB
echo -n ABC >ABC
echo -n ABCD >ABCD
echo -n ABCDE >ABCDE
echo -n ABCDEF >ABCDEF
cat busybox >A_bbox
for f in A*; do
echo uuencode $f
./uuencode $f <$f >u_$f
./uuencode -m $f <$f >m_$f
done
mkdir unpk_u unpk_m 2>/dev/null
for f in u_*; do
./uudecode <$f -o unpk_u/${f:2}
diff -a ${f:2} unpk_u/${f:2} >/dev/null 2>&1
echo uudecode $f: $?
done
for f in m_*; do
./uudecode <$f -o unpk_m/${f:2}
diff -a ${f:2} unpk_m/${f:2} >/dev/null 2>&1
echo uudecode $f: $?
done
*/