/hphp/runtime/ext_zend_compat/php-src/ext/standard/base64.cpp

/*
   +----------------------------------------------------------------------+
   | PHP Version 5                                                        |
   +----------------------------------------------------------------------+
   | Copyright (c) 1997-2013 The PHP Group                                |
   +----------------------------------------------------------------------+
   | This source file is subject to version 3.01 of the PHP license,      |
   | that is bundled with this package in the file LICENSE, and is        |
   | available through the world-wide-web at the following url:           |
   | http://www.php.net/license/3_01.txt                                  |
   | If you did not receive a copy of the PHP license and are unable to   |
   | obtain it through the world-wide-web, please send a note to          |
   | license@php.net so we can mail you a copy immediately.               |
   +----------------------------------------------------------------------+
   | Author: Jim Winstead <jimw@php.net>                                  |
   +----------------------------------------------------------------------+
 */
/* $Id$ */

#include <string.h>

#include "php.h"
#include "base64.h"

/* {{{ base64 tables */
static const char base64_table[] = {
  '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', '+', '/', '\0'
};

static const char base64_pad = '=';

static const short base64_reverse_table[256] = {
  -2, -2, -2, -2, -2, -2, -2, -2, -2, -1, -1, -2, -2, -1, -2, -2,
  -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2,
  -1, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, 62, -2, -2, -2, 63,
  52, 53, 54, 55, 56, 57, 58, 59, 60, 61, -2, -2, -2, -2, -2, -2,
  -2,  0,  1,  2,  3,  4,  5,  6,  7,  8,  9, 10, 11, 12, 13, 14,
  15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, -2, -2, -2, -2, -2,
  -2, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,
  41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, -2, -2, -2, -2, -2,
  -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2,
  -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2,
  -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2,
  -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2,
  -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2,
  -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2,
  -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2,
  -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2
};
/* }}} */

PHPAPI unsigned char *php_base64_encode(const unsigned char *str, int length, int *ret_length) /* {{{ */
{
  const unsigned char *current = str;
  unsigned char *p;
  unsigned char *result;

  if (length < 0) {
    if (ret_length != NULL) {
      *ret_length = 0;
    }
    return NULL;
  }

  result = (unsigned char *) safe_emalloc((length + 2) / 3, 4 * sizeof(char), 1);
  p = result;

  while (length > 2) { /* keep going until we have less than 24 bits */
    *p++ = base64_table[current[0] >> 2];
    *p++ = base64_table[((current[0] & 0x03) << 4) + (current[1] >> 4)];
    *p++ = base64_table[((current[1] & 0x0f) << 2) + (current[2] >> 6)];
    *p++ = base64_table[current[2] & 0x3f];

    current += 3;
    length -= 3; /* we just handle 3 octets of data */
  }

  /* now deal with the tail end of things */
  if (length != 0) {
    *p++ = base64_table[current[0] >> 2];
    if (length > 1) {
      *p++ = base64_table[((current[0] & 0x03) << 4) + (current[1] >> 4)];
      *p++ = base64_table[(current[1] & 0x0f) << 2];
      *p++ = base64_pad;
    } else {
      *p++ = base64_table[(current[0] & 0x03) << 4];
      *p++ = base64_pad;
      *p++ = base64_pad;
    }
  }
  if (ret_length != NULL) {
    *ret_length = (int)(p - result);
  }
  *p = '\0';
  return result;
}
/* }}} */

/* {{{ */
/* generate reverse table (do not set index 0 to 64)
static unsigned short base64_reverse_table[256];
#define rt base64_reverse_table
void php_base64_init(void)
{
  char *s = emalloc(10240), *sp;
  char *chp;
  short idx;

  for(ch = 0; ch < 256; ch++) {
    chp = strchr(base64_table, ch);
    if(ch && chp) {
      idx = chp - base64_table;
      if (idx >= 64) idx = -1;
      rt[ch] = idx;
    } else {
      rt[ch] = -1;
    }
  }
  sp = s;
  sprintf(sp, "static const short base64_reverse_table[256] = {\n");
  for(ch =0; ch < 256;) {
    sp = s+strlen(s);
    sprintf(sp, "\t% 3d,% 3d,% 3d,% 3d,% 3d,% 3d,% 3d,% 3d,% 3d,% 3d,% 3d,% 3d,% 3d,% 3d,% 3d,% 3d,\n", rt[ch+0], rt[ch+1], rt[ch+2], rt[ch+3], rt[ch+4], rt[ch+5], rt[ch+6], rt[ch+7], rt[ch+8], rt[ch+9], rt[ch+10], rt[ch+11], rt[ch+12], rt[ch+13], rt[ch+14], rt[ch+15]);
    ch += 16;
  }
  sprintf(sp, "};");
  php_error_docref(NULL TSRMLS_CC, E_NOTICE, "Reverse_table:\n%s", s);
  efree(s);
}
*/
/* }}} */

PHPAPI unsigned char *php_base64_decode(const unsigned char *str, int length, int *ret_length) /* {{{ */
{
  return php_base64_decode_ex(str, length, ret_length, 0);
}
/* }}} */

PHPAPI unsigned char *php_base64_decode_ex(const unsigned char *str, int length, int *ret_length, zend_bool strict) /* {{{ */
{
  const unsigned char *current = str;
  int ch, i = 0, j = 0, k;
  /* this sucks for threaded environments */
  unsigned char *result;

  result = (unsigned char *)safe_emalloc(length, 1, 1);

  /* run through the whole string, converting as we go */
  while ((ch = *current++) != '\0' && length-- > 0) {
    if (ch == base64_pad) {
      if (*current != '=' && ((i % 4) == 1 || (strict && length > 0))) {
        if ((i % 4) != 1) {
          while (isspace(*(++current))) {
            continue;
          }
          if (*current == '\0') {
            continue;
          }
        }
        efree(result);
        return NULL;
      }
      continue;
    }

    ch = base64_reverse_table[ch];
    if ((!strict && ch < 0) || ch == -1) { /* a space or some other separator character, we simply skip over */
      continue;
    } else if (ch == -2) {
      efree(result);
      return NULL;
    }

    switch(i % 4) {
    case 0:
      result[j] = ch << 2;
      break;
    case 1:
      result[j++] |= ch >> 4;
      result[j] = (ch & 0x0f) << 4;
      break;
    case 2:
      result[j++] |= ch >>2;
      result[j] = (ch & 0x03) << 6;
      break;
    case 3:
      result[j++] |= ch;
      break;
    }
    i++;
  }

  k = j;
  /* mop things up if we ended on a boundary */
  if (ch == base64_pad) {
    switch(i % 4) {
    case 1:
      efree(result);
      return NULL;
    case 2:
      k++;
    case 3:
      result[k] = 0;
    }
  }
  if(ret_length) {
    *ret_length = j;
  }
  result[j] = '\0';
  return result;
}
/* }}} */

/* {{{ proto string base64_encode(string str)
   Encodes string using MIME base64 algorithm */
PHP_FUNCTION(base64_encode)
{
  char *str;
  unsigned char *result;
  int str_len, ret_length;

  if (zend_parse_parameters(ZEND_NUM_ARGS() TSRMLS_CC, "s", &str, &str_len) == FAILURE) {
    return;
  }
  result = php_base64_encode((unsigned char*)str, str_len, &ret_length);
  if (result != NULL) {
    RETVAL_STRINGL((char*)result, ret_length, 0);
  } else {
    RETURN_FALSE;
  }
}
/* }}} */

/* {{{ proto string base64_decode(string str[, bool strict])
   Decodes string using MIME base64 algorithm */
PHP_FUNCTION(base64_decode)
{
  char *str;
  unsigned char *result;
  zend_bool strict = 0;
  int str_len, ret_length;

  if (zend_parse_parameters(ZEND_NUM_ARGS() TSRMLS_CC, "s|b", &str, &str_len, &strict) == FAILURE) {
    return;
  }
  result = php_base64_decode_ex((unsigned char*)str, str_len, &ret_length, strict);
  if (result != NULL) {
    RETVAL_STRINGL((char*)result, ret_length, 0);
  } else {
    RETURN_FALSE;
  }
}
/* }}} */

/*
 * Local variables:
 * tab-width: 4
 * c-basic-offset: 4
 * End:
 * vim600: sw=4 ts=4 fdm=marker
 * vim<600: sw=4 ts=4
 */