release/src/router/nettle/examples/base16enc.c

   1 /* base16enc -- an encoder for base16
   2  *
   3  * Copyright (C) 2006, 2012 Jeronimo Pellegrini, Niels Möller
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU Lesser General Public License as published by
   7  * the Free Software Foundation; either version 2.1 of the License, or (at your
   8  * option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful, but
  11  * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  12  * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public
  13  * License for more details.
  14  *
  15  * You should have received a copy of the GNU Lesser General Public License
  16  * along with the nettle library; see the file COPYING.LIB.  If not, write to
  17  * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
  18  * MA 02111-1301, USA.
  19  */
  20
  21 #if HAVE_CONFIG_H
  22 # include "config.h"
  23 #endif
  24
  25 #include <errno.h>
  26 #include <stdlib.h>
  27 #include <stdio.h>
  28 #include <string.h>
  29 #ifdef WIN32
  30 #include <fcntl.h>
  31 #endif
  32
  33 #include "base16.h"
  34
  35 #include "io.h"
  36
  37 /* The number of bytes read in each iteration, we do one line at a time: */
  38 #define CHUNK_SIZE 36
  39
  40 /* The *maximum* size of an encoded chunk: */
  41 #define ENCODED_SIZE BASE16_ENCODE_LENGTH(CHUNK_SIZE)
  42
  43 /*
  44  * Reads bytes from standard input and writes base64-encoded
  45  * on standard output.
  46  */
  47 int
  48 main(int argc UNUSED, char **argv UNUSED)
  49 {
  50
  51 #ifdef WIN32
  52   _setmode(0, O_BINARY);
  53 #endif
  54
  55   /* There is no context to initialize. */
  56
  57   for (;;)
  58     {
  59       /* "buffer" will hold the bytes from disk: */
  60       uint8_t buffer[CHUNK_SIZE];
  61       /* "result" will hold bytes before output: */
  62       uint8_t result[ENCODED_SIZE + 1];
  63       unsigned nbytes; /* Number of bytes read from stdin */
  64       int encoded_bytes; /* Total number of bytes encoded per iteration */
  65
  66       nbytes = fread(buffer,1,CHUNK_SIZE,stdin);
  67
  68       /* We overwrite result with more data */
  69       base16_encode_update(result, nbytes, buffer);
  70       encoded_bytes = BASE16_ENCODE_LENGTH(nbytes);
  71       result[encoded_bytes++] = '\n';
  72
  73       if (nbytes < CHUNK_SIZE)
  74         {
  75           if (ferror(stdin))
  76             {
  77               werror ("Error reading file: %s\n", strerror(errno));
  78               return EXIT_FAILURE;
  79             }
  80           if (!write_string (stdout, encoded_bytes, result)
  81               || fflush (stdout) != 0)
  82             {
  83               werror ("Error writing file: %s\n", strerror(errno));
  84               return EXIT_FAILURE;
  85             }
  86           return EXIT_SUCCESS;
  87         }
  88       /* The result vector is printed */
  89       if (!write_string(stdout,encoded_bytes, result))
  90         {
  91           werror ("Error writing file: %s\n", strerror(errno));
  92           return EXIT_FAILURE;
  93         }
  94     }
  95 }
  96