gnulib-local/lib/html-styled-ostream.oo.c

   1 /* Output stream for CSS styled text, producing HTML output.
   2    Copyright (C) 2006-2007 Free Software Foundation, Inc.
   3    Written by Bruno Haible <bruno@clisp.org>, 2006.
   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 <http://www.gnu.org/licenses/>.  */
  17
  18 #include <config.h>
  19
  20 /* Specification.  */
  21 #include "html-styled-ostream.h"
  22
  23 #include <errno.h>
  24 #include <fcntl.h>
  25 #include <stdlib.h>
  26 #include <unistd.h>
  27
  28 #include "html-ostream.h"
  29
  30 #include "binary-io.h"
  31 #ifndef O_TEXT
  32 # define O_TEXT 0
  33 #endif
  34
  35 #include "error.h"
  36 #include "safe-read.h"
  37 #include "xalloc.h"
  38 #include "gettext.h"
  39
  40 #define _(str) gettext (str)
  41
  42
  43 struct html_styled_ostream : struct styled_ostream
  44 {
  45 fields:
  46   /* The destination stream.  */
  47   ostream_t destination;
  48   /* A HTML aware wrapper around the destination stream.  */
  49   html_ostream_t html_destination;
  50 };
  51
  52 /* Implementation of ostream_t methods.  */
  53
  54 static void
  55 html_styled_ostream::write_mem (html_styled_ostream_t stream,
  56                                 const void *data, size_t len)
  57 {
  58   html_ostream_write_mem (stream->html_destination, data, len);
  59 }
  60
  61 static void
  62 html_styled_ostream::flush (html_styled_ostream_t stream)
  63 {
  64   html_ostream_flush (stream->html_destination);
  65 }
  66
  67 static void
  68 html_styled_ostream::free (html_styled_ostream_t stream)
  69 {
  70   html_ostream_free (stream->html_destination);
  71   ostream_write_str (stream->destination, "</body>\n");
  72   ostream_write_str (stream->destination, "</html>\n");
  73 }
  74
  75 /* Implementation of styled_ostream_t methods.  */
  76
  77 static void
  78 html_styled_ostream::begin_use_class (html_styled_ostream_t stream,
  79                                       const char *classname)
  80 {
  81   html_ostream_begin_span (stream->html_destination, classname);
  82 }
  83
  84 static void
  85 html_styled_ostream::end_use_class (html_styled_ostream_t stream,
  86                                     const char *classname)
  87 {
  88   html_ostream_end_span (stream->html_destination, classname);
  89 }
  90
  91 /* Constructor.  */
  92
  93 html_styled_ostream_t
  94 html_styled_ostream_create (ostream_t destination, const char *css_filename)
  95 {
  96   html_styled_ostream_t stream =
  97     XMALLOC (struct html_styled_ostream_representation);
  98
  99   stream->base.base.vtable = &html_styled_ostream_vtable;
 100   stream->destination = destination;
 101   stream->html_destination = html_ostream_create (destination);
 102
 103   ostream_write_str (stream->destination, "<?xml version=\"1.0\"?>\n");
 104   /* HTML 4.01 or XHTML 1.0?
 105      Use HTML 4.01.  This is conservative.  Before switching to XHTML 1.0,
 106      verify that in the output
 107        - all HTML element names are in lowercase,
 108        - all empty elements are denoted like <br/> or <p></p>,
 109        - every attribute specification is in assignment form, like
 110          <table border="1">,
 111        - every <a name="..."> element also has an 'id' attribute,
 112        - special characters like < > & " are escaped in the <style> and
 113          <script> elements.  */
 114   ostream_write_str (stream->destination,
 115                      "<!DOCTYPE HTML PUBLIC \"-//W3C//DTD HTML 4.01//EN\" \"http://www.w3.org/TR/html4/strict.dtd\">\n");
 116   ostream_write_str (stream->destination, "<html>\n");
 117   ostream_write_str (stream->destination, "<head>\n");
 118   if (css_filename != NULL)
 119     {
 120       ostream_write_str (stream->destination, "<style type=\"text/css\">\n"
 121                                               "<!--\n");
 122
 123       /* Include the contents of CSS_FILENAME literally.  */
 124       {
 125         int fd;
 126         char buf[4096];
 127
 128         fd = open (css_filename, O_RDONLY | O_TEXT);
 129         if (fd < 0)
 130           error (EXIT_FAILURE, errno,
 131                  _("error while opening \"%s\" for reading"),
 132                  css_filename);
 133
 134         for (;;)
 135           {
 136             size_t n_read = safe_read (fd, buf, sizeof (buf));
 137             if (n_read == SAFE_READ_ERROR)
 138               error (EXIT_FAILURE, errno, _("error reading \"%s\""),
 139                      css_filename);
 140             if (n_read == 0)
 141               break;
 142
 143             ostream_write_mem (stream->destination, buf, n_read);
 144           }
 145
 146         if (close (fd) < 0)
 147           error (EXIT_FAILURE, errno, _("error after reading \"%s\""),
 148                  css_filename);
 149       }
 150
 151       ostream_write_str (stream->destination, "-->\n"
 152                                               "</style>\n");
 153     }
 154   ostream_write_str (stream->destination, "</head>\n");
 155   ostream_write_str (stream->destination, "<body>\n");
 156
 157   return stream;
 158 }