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215 lines
4.8 KiB
C
215 lines
4.8 KiB
C
/* vi: set sw=4 ts=4: */
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/*
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* Copyright 2003, Glenn McGrath
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*
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* Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
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*
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* Based on specification from
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* http://www.opengroup.org/onlinepubs/007904975/utilities/uuencode.html
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*
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* Bugs: the spec doesn't mention anything about "`\n`\n" prior to the
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* "end" line
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*/
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#include "libbb.h"
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static void read_stduu(FILE *src_stream, FILE *dst_stream)
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{
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char *line;
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while ((line = xmalloc_getline(src_stream)) != NULL) {
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int length;
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char *line_ptr = line;
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if (strcmp(line, "end") == 0) {
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return;
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}
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length = ((*line_ptr - 0x20) & 0x3f)* 4 / 3;
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if (length <= 0) {
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/* Ignore the "`\n" line, why is it even in the encode file ? */
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continue;
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}
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if (length > 60) {
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bb_error_msg_and_die("line too long");
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}
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line_ptr++;
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/* Tolerate an overly long line to accomodate a possible exta '`' */
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if (strlen(line_ptr) < (size_t)length) {
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bb_error_msg_and_die("short file");
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}
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while (length > 0) {
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/* Merge four 6 bit chars to three 8 bit chars */
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fputc(((line_ptr[0] - 0x20) & 077) << 2 | ((line_ptr[1] - 0x20) & 077) >> 4, dst_stream);
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line_ptr++;
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length--;
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if (length == 0) {
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break;
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}
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fputc(((line_ptr[0] - 0x20) & 077) << 4 | ((line_ptr[1] - 0x20) & 077) >> 2, dst_stream);
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line_ptr++;
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length--;
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if (length == 0) {
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break;
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}
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fputc(((line_ptr[0] - 0x20) & 077) << 6 | ((line_ptr[1] - 0x20) & 077), dst_stream);
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line_ptr += 2;
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length -= 2;
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}
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free(line);
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}
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bb_error_msg_and_die("short file");
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}
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static void read_base64(FILE *src_stream, FILE *dst_stream)
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{
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int term_count = 1;
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while (1) {
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char translated[4];
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int count = 0;
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while (count < 4) {
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char *table_ptr;
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int ch;
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/* Get next _valid_ character.
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* global vector bb_uuenc_tbl_base64[] contains this string:
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* "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=\n"
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*/
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do {
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ch = fgetc(src_stream);
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if (ch == EOF) {
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bb_error_msg_and_die("short file");
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}
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table_ptr = strchr(bb_uuenc_tbl_base64, ch);
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} while (table_ptr == NULL);
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/* Convert encoded character to decimal */
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ch = table_ptr - bb_uuenc_tbl_base64;
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if (*table_ptr == '=') {
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if (term_count == 0) {
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translated[count] = '\0';
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break;
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}
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term_count++;
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} else if (*table_ptr == '\n') {
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/* Check for terminating line */
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if (term_count == 5) {
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return;
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}
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term_count = 1;
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continue;
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} else {
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translated[count] = ch;
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count++;
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term_count = 0;
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}
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}
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/* Merge 6 bit chars to 8 bit */
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if (count > 1) {
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fputc(translated[0] << 2 | translated[1] >> 4, dst_stream);
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}
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if (count > 2) {
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fputc(translated[1] << 4 | translated[2] >> 2, dst_stream);
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}
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if (count > 3) {
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fputc(translated[2] << 6 | translated[3], dst_stream);
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}
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}
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}
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int uudecode_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
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int uudecode_main(int argc, char **argv)
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{
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FILE *src_stream = stdin;
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char *outname = NULL;
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char *line;
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opt_complementary = "?1"; /* 1 argument max */
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getopt32(argv, "o:", &outname);
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argv += optind;
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if (argv[0])
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src_stream = xfopen(argv[0], "r");
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/* Search for the start of the encoding */
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while ((line = xmalloc_getline(src_stream)) != NULL) {
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void (*decode_fn_ptr)(FILE * src, FILE * dst);
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char *line_ptr;
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FILE *dst_stream;
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int mode;
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if (strncmp(line, "begin-base64 ", 13) == 0) {
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line_ptr = line + 13;
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decode_fn_ptr = read_base64;
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} else if (strncmp(line, "begin ", 6) == 0) {
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line_ptr = line + 6;
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decode_fn_ptr = read_stduu;
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} else {
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free(line);
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continue;
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}
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/* begin line found. decode and exit */
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mode = strtoul(line_ptr, NULL, 8);
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if (outname == NULL) {
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outname = strchr(line_ptr, ' ');
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if ((outname == NULL) || (*outname == '\0')) {
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break;
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}
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outname++;
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}
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dst_stream = stdout;
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if (NOT_LONE_DASH(outname)) {
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dst_stream = xfopen(outname, "w");
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chmod(outname, mode & (S_IRWXU | S_IRWXG | S_IRWXO));
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}
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free(line);
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decode_fn_ptr(src_stream, dst_stream);
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/* fclose_if_not_stdin(src_stream); - redundant */
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return EXIT_SUCCESS;
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}
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bb_error_msg_and_die("no 'begin' line");
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}
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/* Test script.
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Put this into an empty dir with busybox binary, an run.
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#!/bin/sh
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test -x busybox || { echo "No ./busybox?"; exit; }
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ln -sf busybox uudecode
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ln -sf busybox uuencode
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>A_null
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echo -n A >A
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echo -n AB >AB
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echo -n ABC >ABC
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echo -n ABCD >ABCD
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echo -n ABCDE >ABCDE
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echo -n ABCDEF >ABCDEF
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cat busybox >A_bbox
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for f in A*; do
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echo uuencode $f
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./uuencode $f <$f >u_$f
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./uuencode -m $f <$f >m_$f
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done
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mkdir unpk_u unpk_m 2>/dev/null
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for f in u_*; do
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./uudecode <$f -o unpk_u/${f:2}
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diff -a ${f:2} unpk_u/${f:2} >/dev/null 2>&1
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echo uudecode $f: $?
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done
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for f in m_*; do
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./uudecode <$f -o unpk_m/${f:2}
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diff -a ${f:2} unpk_m/${f:2} >/dev/null 2>&1
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echo uudecode $f: $?
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done
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*/
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