source: MondoRescue/trunk/mindi-busybox/coreutils/uuencode.c@ 929

/* vi: set sw=4 ts=4: */
/*
 *  Copyright (C) 2000 by Glenn McGrath
 *
 *  based on the function base64_encode from http.c in wget v1.6
 *  Copyright (C) 1995, 1996, 1997, 1998, 2000 Free Software Foundation, Inc.
 *
 *  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 <string.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>
#include "busybox.h"

/* Conversion table.  for base 64 */
static const char tbl_base64[65] = {
    'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H',
    'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P',
    'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X',
    'Y', 'Z', 'a', 'b', 'c', 'd', 'e', 'f',
    'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n',
    'o', 'p', 'q', 'r', 's', 't', 'u', 'v',
    'w', 'x', 'y', 'z', '0', '1', '2', '3',
    '4', '5', '6', '7', '8', '9', '+', '/',
    '=' /* termination character */
};

static const char tbl_std[65] = {
    '`', '!', '"', '#', '$', '%', '&', '\'',
    '(', ')', '*', '+', ',', '-', '.', '/',
    '0', '1', '2', '3', '4', '5', '6', '7',
    '8', '9', ':', ';', '<', '=', '>', '?',
    '@', 'A', 'B', 'C', 'D', 'E', 'F', 'G',
    'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O',
    'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W',
    'X', 'Y', 'Z', '[', '\\', ']', '^', '_',
    '`' /* termination character */
};

/*
 * Encode the string S of length LENGTH to base64 format and place it
 * to STORE.  STORE will be 0-terminated, and must point to a writable
 * buffer of at least 1+BASE64_LENGTH(length) bytes.
 * where BASE64_LENGTH(len) = (4 * ((LENGTH + 2) / 3))
 */
static void uuencode (const unsigned char *s, char *store, const int length, const char *tbl)
{
    int i;
    char *p = store;

    /* Transform the 3x8 bits to 4x6 bits, as required by base64.  */
    for (i = 0; i < length; i += 3) {
        *p++ = tbl[s[0] >> 2];
        *p++ = tbl[((s[0] & 3) << 4) + (s[1] >> 4)];
        *p++ = tbl[((s[1] & 0xf) << 2) + (s[2] >> 6)];
        *p++ = tbl[s[2] & 0x3f];
        s += 3;
    }
    /* Pad the result if necessary...  */
    if (i == length + 1) {
        *(p - 1) = tbl[64];
    }
    else if (i == length + 2) {
        *(p - 1) = *(p - 2) = tbl[64];
    }
    /* ...and zero-terminate it.  */
    *p = '\0';
}

#define SRC_BUF_SIZE    45  // This *MUST* be a multiple of 3
#define DST_BUF_SIZE    4 * ((SRC_BUF_SIZE + 2) / 3)
int uuencode_main(int argc, char **argv)
{
    const size_t src_buf_size = SRC_BUF_SIZE;
    const size_t dst_buf_size = DST_BUF_SIZE;
    size_t write_size = dst_buf_size;
    struct stat stat_buf;
    FILE *src_stream = stdin;
    const char *tbl;
    size_t size;
    mode_t mode;
    RESERVE_CONFIG_BUFFER(src_buf, SRC_BUF_SIZE + 1);
    RESERVE_CONFIG_BUFFER(dst_buf, DST_BUF_SIZE + 1);

    tbl = tbl_std;
    if (bb_getopt_ulflags(argc, argv, "m") & 1) {
        tbl = tbl_base64;
    }

    switch (argc - optind) {
        case 2:
            src_stream = bb_xfopen(argv[optind], "r");
            xstat(argv[optind], &stat_buf);
            mode = stat_buf.st_mode & (S_IRWXU | S_IRWXG | S_IRWXO);
            if (src_stream == stdout) {
                puts("NULL");
            }
            break;
        case 1:
            mode = 0666 & ~umask(0666);
            break;
        default:
            bb_show_usage();
    }

    bb_printf("begin%s %o %s", tbl == tbl_std ? "" : "-base64", mode, argv[argc - 1]);

    while ((size = fread(src_buf, 1, src_buf_size, src_stream)) > 0) {
        if (size != src_buf_size) {
            /* write_size is always 60 until the last line */
            write_size=(4 * ((size + 2) / 3));
            /* pad with 0s so we can just encode extra bits */
            memset(&src_buf[size], 0, src_buf_size - size);
        }
        /* Encode the buffer we just read in */
        uuencode((unsigned char*)src_buf, dst_buf, size, tbl);

        putchar('\n');
        if (tbl == tbl_std) {
            putchar(tbl[size]);
        }
        if (fwrite(dst_buf, 1, write_size, stdout) != write_size) {
            bb_perror_msg_and_die(bb_msg_write_error);
        }
    }
    bb_printf(tbl == tbl_std ? "\n`\nend\n" : "\n====\n");

    bb_xferror(src_stream, "source");   /* TODO - Fix this! */

    bb_fflush_stdout_and_exit(EXIT_SUCCESS);
}