1  /* Convert ASCII quotations to Unicode quotations.
       2     Copyright (C) 2014-2016 Free Software Foundation, Inc.
       3     Written by Daiki Ueno <ueno@gnu.org>, 2014.
       4  
       5     This program is free software: you can redistribute it and/or modify
       6     it under the terms of the GNU General Public License as published by
       7     the Free Software Foundation; either version 3 of the License, or
       8     (at your option) any later version.
       9  
      10     This program is distributed in the hope that it will be useful,
      11     but WITHOUT ANY WARRANTY; without even the implied warranty of
      12     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
      13     GNU General Public License for more details.
      14  
      15     You should have received a copy of the GNU General Public License
      16     along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
      17  
      18  #ifdef HAVE_CONFIG_H
      19  # include <config.h>
      20  #endif
      21  
      22  /* Specification.  */
      23  #include "filters.h"
      24  
      25  #include "quote.h"
      26  #include <stdbool.h>
      27  #include <stdlib.h>
      28  #include <string.h>
      29  #include "xalloc.h"
      30  
      31  #define BOLD_START "\x1b[1m"
      32  #define BOLD_END "\x1b[0m"
      33  
      34  struct result
      35  {
      36    char *output;
      37    char *offset;
      38    bool bold;
      39  };
      40  
      41  static void
      42  convert_quote_callback (char quote, const char *quoted, size_t quoted_length,
      43                          void *data)
      44  {
      45    struct result *result = data;
      46  
      47    switch (quote)
      48      {
      49      case '\0':
      50        memcpy (result->offset, quoted, quoted_length);
      51        result->offset += quoted_length;
      52        break;
      53  
      54      case '"':
      55        /* U+201C: LEFT DOUBLE QUOTATION MARK */
      56        memcpy (result->offset, "\xe2\x80\x9c", 3);
      57        result->offset += 3;
      58        if (result->bold)
      59          {
      60            memcpy (result->offset, BOLD_START, 4);
      61            result->offset += 4;
      62          }
      63        memcpy (result->offset, quoted, quoted_length);
      64        result->offset += quoted_length;
      65        if (result->bold)
      66          {
      67            memcpy (result->offset, BOLD_END, 4);
      68            result->offset += 4;
      69          }
      70        /* U+201D: RIGHT DOUBLE QUOTATION MARK */
      71        memcpy (result->offset, "\xe2\x80\x9d", 3);
      72        result->offset += 3;
      73        break;
      74  
      75      case '\'':
      76        /* U+2018: LEFT SINGLE QUOTATION MARK */
      77        memcpy (result->offset, "\xe2\x80\x98", 3);
      78        result->offset += 3;
      79        if (result->bold)
      80          {
      81            memcpy (result->offset, BOLD_START, 4);
      82            result->offset += 4;
      83          }
      84        memcpy (result->offset, quoted, quoted_length);
      85        result->offset += quoted_length;
      86        if (result->bold)
      87          {
      88            memcpy (result->offset, BOLD_END, 4);
      89            result->offset += 4;
      90          }
      91        /* U+2019: RIGHT SINGLE QUOTATION MARK */
      92        memcpy (result->offset, "\xe2\x80\x99", 3);
      93        result->offset += 3;
      94        break;
      95      }
      96  }
      97  
      98  /* This is a direct translation of po/quot.sed and po/boldquot.sed.  */
      99  static void
     100  convert_ascii_quote_to_unicode (const char *input, size_t input_len,
     101                                  char **output_p, size_t *output_len_p,
     102                                  bool bold)
     103  {
     104    const char *p;
     105    size_t quote_count;
     106    struct result result;
     107  
     108    /* Count the number of quotation characters.  */
     109    quote_count = 0;
     110    for (p = input; p < input + input_len; p++)
     111      {
     112        size_t len;
     113  
     114        p = strpbrk (p, "`'\"");
     115        if (!p)
     116          break;
     117  
     118        len = strspn (p, "`'\"");
     119        quote_count += len;
     120        p += len;
     121      }
     122  
     123    /* Large enough.  */
     124    result.output = XNMALLOC (input_len - quote_count
     125                              + (bold ? 7 : 3) * quote_count + 1,
     126                              char);
     127    result.offset = result.output;
     128    result.bold = bold;
     129  
     130    scan_quoted (input, input_len, convert_quote_callback, &result);
     131  
     132    *output_p = result.output;
     133    *output_len_p = result.offset - result.output;
     134  }
     135  
     136  void
     137  ascii_quote_to_unicode (const char *input, size_t input_len,
     138                          char **output_p, size_t *output_len_p)
     139  {
     140    convert_ascii_quote_to_unicode (input, input_len,
     141                                    output_p, output_len_p,
     142                                    false);
     143  }
     144  
     145  void
     146  ascii_quote_to_unicode_bold (const char *input, size_t input_len,
     147                               char **output_p, size_t *output_len_p)
     148  {
     149    convert_ascii_quote_to_unicode (input, input_len,
     150                                    output_p, output_len_p,
     151                                    true);
     152  }