release/src/router/nettle/examples/base64enc.c

   1 /* base64enc -- an encoder for base64
   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 "base64.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 54
  39
  40 /* The *maximum* size of an encoded chunk: */
  41 #define ENCODED_SIZE BASE64_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   struct base64_encode_ctx b64_ctx;
  51
  52   /* Init the context: */
  53   base64_encode_init(&b64_ctx);
  54
  55 #ifdef WIN32
  56   _setmode(0, O_BINARY);
  57 #endif
  58
  59   for (;;)
  60     {
  61       /* "buffer" will hold the bytes from disk: */
  62       uint8_t buffer[CHUNK_SIZE];
  63       /* "result" is the result vector: */
  64       uint8_t result[ENCODED_SIZE + BASE64_ENCODE_FINAL_LENGTH + 1];
  65       unsigned nbytes; /* Number of bytes read from stdin */
  66       int encoded_bytes; /* total number of bytes encoded per iteration */
  67       nbytes = fread(buffer,1,CHUNK_SIZE,stdin);
  68
  69       /* We overwrite result with more data */
  70       encoded_bytes = base64_encode_update(&b64_ctx, result, nbytes, buffer);
  71
  72       if (nbytes < CHUNK_SIZE)
  73         {
  74           if (ferror(stdin))
  75             {
  76               werror ("Error reading file: %s\n", strerror(errno));
  77               return EXIT_FAILURE;
  78             }
  79           encoded_bytes += base64_encode_final(&b64_ctx,result + encoded_bytes);
  80
  81           result[encoded_bytes++] = '\n';
  82           if (!write_string (stdout, encoded_bytes, result)
  83               || fflush (stdout) != 0)
  84             {
  85               werror ("Error writing file: %s\n", strerror(errno));
  86               return EXIT_FAILURE;
  87             }
  88           return EXIT_SUCCESS;
  89         }
  90
  91       /* The result vector is written */
  92       result[encoded_bytes++] = '\n';
  93       if (!write_string (stdout, encoded_bytes, result))
  94         {
  95           werror ("Error writing file: %s\n", strerror(errno));
  96           return EXIT_FAILURE;
  97         }
  98     }
  99 }