Imported Upstream version 0.9.1upstream/0.9.1

1 files changed, 212 insertions, 0 deletions

diff --git a/lib/unilbrk/ulc-possible-linebreaks.c b/lib/unilbrk/ulc-possible-linebreaks.c
new file mode 100644
index 00000000..cb952419
--- /dev/null
+++ b/lib/unilbrk/ulc-possible-linebreaks.c
@@ -0,0 +1,212 @@
+/* Line breaking of strings.
+   Copyright (C) 2001-2003, 2006-2009 Free Software Foundation, Inc.
+   Written by Bruno Haible <bruno@clisp.org>, 2001.
+
+   This program is free software: you can redistribute it and/or modify it
+   under the terms of the GNU Lesser General Public License as published
+   by the Free Software Foundation; either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
+
+#include <config.h>
+
+/* Specification.  */
+#include "unilbrk.h"
+
+#include <stdlib.h>
+#include <string.h>
+
+#include "c-ctype.h"
+#include "uniconv.h"
+#include "unilbrk/ulc-common.h"
+
+/* Line breaking of a string in an arbitrary encoding.
+
+   We convert the input string to Unicode.
+
+   The standardized Unicode encodings are UTF-8, UCS-2, UCS-4, UTF-16,
+   UTF-16BE, UTF-16LE, UTF-7.  UCS-2 supports only characters up to
+   \U0000FFFF.  UTF-16 and variants support only characters up to
+   \U0010FFFF.  UTF-7 is way too complex and not supported by glibc-2.1.
+   UCS-4 specification leaves doubts about endianness and byte order mark.
+   glibc currently interprets it as big endian without byte order mark,
+   but this is not backed by an RFC.  So we use UTF-8. It supports
+   characters up to \U7FFFFFFF and is unambiguously defined.  */
+
+void
+ulc_possible_linebreaks (const char *s, size_t n, const char *encoding,
+			 char *p)
+{
+  if (n > 0)
+    {
+      if (is_utf8_encoding (encoding))
+	u8_possible_linebreaks ((const uint8_t *) s, n, encoding, p);
+      else
+	{
+	  /* Convert the string to UTF-8 and build a translation table
+	     from offsets into s to offsets into the translated string.  */
+	  size_t *offsets = (size_t *) malloc (n * sizeof (size_t));
+
+	  if (offsets != NULL)
+	    {
+	      uint8_t *t;
+	      size_t m;
+
+	      t = u8_conv_from_encoding (encoding, iconveh_question_mark,
+					 s, n, offsets, NULL, &m);
+	      if (t != NULL)
+		{
+		  char *q = (char *) (m > 0 ? malloc (m) : NULL);
+
+		  if (m == 0 || q != NULL)
+		    {
+		      size_t i;
+
+		      /* Determine the possible line breaks of the UTF-8
+			 string.  */
+		      u8_possible_linebreaks (t, m, encoding, q);
+
+		      /* Translate the result back to the original string.  */
+		      memset (p, UC_BREAK_PROHIBITED, n);
+		      for (i = 0; i < n; i++)
+			if (offsets[i] != (size_t)(-1))
+			  p[i] = q[offsets[i]];
+
+		      free (q);
+		      free (t);
+		      free (offsets);
+		      return;
+		    }
+		  free (t);
+		}
+	      free (offsets);
+	    }
+
+	  /* Impossible to convert.  */
+#if C_CTYPE_ASCII
+	  if (is_all_ascii (s, n))
+	    {
+	      /* ASCII is a subset of UTF-8.  */
+	      u8_possible_linebreaks ((const uint8_t *) s, n, encoding, p);
+	      return;
+	    }
+#endif
+	  /* We have a non-ASCII string and cannot convert it.
+	     Don't produce line breaks except those already present in the
+	     input string.  All we assume here is that the encoding is
+	     minimally ASCII compatible.  */
+	  {
+	    const char *s_end = s + n;
+	    while (s < s_end)
+	      {
+		*p = (*s == '\n' ? UC_BREAK_MANDATORY : UC_BREAK_PROHIBITED);
+		s++;
+		p++;
+	      }
+	  }
+	}
+    }
+}
+
+
+#ifdef TEST
+
+#include <stdio.h>
+#include <locale.h>
+#include <string.h>
+
+/* Read the contents of an input stream, and return it, terminated with a NUL
+   byte. */
+char *
+read_file (FILE *stream)
+{
+#define BUFSIZE 4096
+  char *buf = NULL;
+  int alloc = 0;
+  int size = 0;
+  int count;
+
+  while (! feof (stream))
+    {
+      if (size + BUFSIZE > alloc)
+	{
+	  alloc = alloc + alloc / 2;
+	  if (alloc < size + BUFSIZE)
+	    alloc = size + BUFSIZE;
+	  buf = realloc (buf, alloc);
+	  if (buf == NULL)
+	    {
+	      fprintf (stderr, "out of memory\n");
+	      exit (1);
+	    }
+	}
+      count = fread (buf + size, 1, BUFSIZE, stream);
+      if (count == 0)
+	{
+	  if (ferror (stream))
+	    {
+	      perror ("fread");
+	      exit (1);
+	    }
+	}
+      else
+	size += count;
+    }
+  buf = realloc (buf, size + 1);
+  if (buf == NULL)
+    {
+      fprintf (stderr, "out of memory\n");
+      exit (1);
+    }
+  buf[size] = '\0';
+  return buf;
+#undef BUFSIZE
+}
+
+int
+main (int argc, char * argv[])
+{
+  setlocale (LC_CTYPE, "");
+  if (argc == 1)
+    {
+      /* Display all the break opportunities in the input string.  */
+      char *input = read_file (stdin);
+      int length = strlen (input);
+      char *breaks = malloc (length);
+      int i;
+
+      ulc_possible_linebreaks (input, length, locale_charset (), breaks);
+
+      for (i = 0; i < length; i++)
+	{
+	  switch (breaks[i])
+	    {
+	    case UC_BREAK_POSSIBLE:
+	      putc ('|', stdout);
+	      break;
+	    case UC_BREAK_MANDATORY:
+	      break;
+	    case UC_BREAK_PROHIBITED:
+	      break;
+	    default:
+	      abort ();
+	    }
+	  putc (input[i], stdout);
+	}
+
+      free (breaks);
+
+      return 0;
+    }
+  else
+    return 1;
+}
+
+#endif /* TEST */