New module 'striconveha'.

1 files changed, 225 insertions, 0 deletions

diff --git a/lib/striconveha.c b/lib/striconveha.c
new file mode 100644
index 0000000000..9da18c93ef
--- /dev/null
+++ b/lib/striconveha.c
@@ -0,0 +1,225 @@
+/* Character set conversion with error handling and autodetection.
+   Copyright (C) 2002, 2005, 2007 Free Software Foundation, Inc.
+   Written by Bruno Haible.
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 2, 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 General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software Foundation,
+   Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.  */
+
+#include <config.h>
+
+/* Specification.  */
+#include "striconveha.h"
+
+#include <errno.h>
+#include <stdlib.h>
+#include <string.h>
+
+#define SIZEOF(a) (sizeof(a)/sizeof(a[0]))
+
+
+/* Autodetection list.  */
+
+struct autodetect_alias
+{
+  struct autodetect_alias *next;
+  const char *name;
+  const char * const *encodings_to_try;
+};
+
+static const char * const autodetect_utf8_try[] =
+{
+  /* Try UTF-8 first. There are very few ISO-8859-1 inputs that would
+     be valid UTF-8, but many UTF-8 inputs are valid ISO-8859-1.  */
+  "UTF-8", "ISO-8859-1",
+  NULL
+};
+static const char * const autodetect_jp_try[] =
+{
+  /* Try 7-bit encoding first. If the input contains bytes >= 0x80,
+     it will fail.
+     Try EUC-JP next. Short SHIFT_JIS inputs may come out wrong. This
+     is unavoidable. People will condemn SHIFT_JIS.
+     If we tried SHIFT_JIS first, then some short EUC-JP inputs would
+     come out wrong, and people would condemn EUC-JP and Unix, which
+     would not be good.
+     Finally try SHIFT_JIS.  */
+  "ISO-2022-JP-2", "EUC-JP", "SHIFT_JIS",
+  NULL
+};
+static const char * const autodetect_kr_try[] =
+{
+  /* Try 7-bit encoding first. If the input contains bytes >= 0x80,
+     it will fail.
+     Finally try EUC-KR.  */
+  "ISO-2022-KR", "EUC-KR",
+  NULL
+};
+
+static struct autodetect_alias autodetect_predefined[] =
+{
+  { &autodetect_predefined[1], "autodetect_utf8", autodetect_utf8_try },
+  { &autodetect_predefined[2], "autodetect_jp",   autodetect_jp_try },
+  { NULL,                      "autodetect_kr",   autodetect_kr_try }
+};
+
+static struct autodetect_alias *autodetect_list = &autodetect_predefined[0];
+static struct autodetect_alias **autodetect_list_end =
+  &autodetect_predefined[SIZEOF(autodetect_predefined)-1].next;
+
+int
+uniconv_register_autodetect (const char *name,
+			     const char * const *try_in_order)
+{
+  size_t namelen;
+  size_t listlen;
+  size_t memneed;
+  size_t i;
+  char *memory;
+  struct autodetect_alias *new_alias;
+  char *new_name;
+  const char **new_try_in_order;
+
+  /* The TRY_IN_ORDER list must not be empty.  */
+  if (try_in_order[0] == NULL)
+    {
+      errno = EINVAL;
+      return -1;
+    }
+
+  /* We must deep-copy NAME and TRY_IN_ORDER, because they may be allocated
+     with dynamic extent.  */
+  namelen = strlen (name) + 1;
+  memneed = sizeof (struct autodetect_alias) + namelen + sizeof (char *);
+  for (i = 0; try_in_order[i] != NULL; i++)
+    memneed += sizeof (char *) + strlen (try_in_order[i]) + 1;
+  listlen = i;
+
+  memory = (char *) malloc (memneed);
+  if (memory != NULL)
+    {
+      new_alias = (struct autodetect_alias *) memory;
+      memory += sizeof (struct autodetect_alias);
+
+      new_try_in_order = (const char **) memory;
+      memory += (listlen + 1) * sizeof (char *);
+
+      new_name = (char *) memory;
+      memcpy (new_name, name, namelen);
+      memory += namelen;
+
+      for (i = 0; i < listlen; i++)
+	{
+	  size_t len = strlen (try_in_order[i]) + 1;
+	  memcpy (memory, try_in_order[i], len);
+	  new_try_in_order[i] = (const char *) memory;
+	  memory += len;
+	}
+      new_try_in_order[i] = NULL;
+
+      /* Now insert the new alias.  */
+      new_alias->name = new_name;
+      new_alias->encodings_to_try = new_try_in_order;
+      new_alias->next = NULL;
+      /* FIXME: Not multithread-safe.  */
+      *autodetect_list_end = new_alias;
+      autodetect_list_end = &new_alias->next;
+      return 0;
+    }
+  else
+    {
+      errno = ENOMEM;
+      return -1;
+    }
+}
+
+int
+mem_iconveha (const char *src, size_t srclen,
+	      const char *from_codeset, const char *to_codeset,
+	      enum iconv_ilseq_handler handler,
+	      char **resultp, size_t *lengthp)
+{
+  int retval = mem_iconveh (src, srclen, from_codeset, to_codeset, handler,
+			    resultp, lengthp);
+  if (retval >= 0 || errno != EINVAL)
+    return retval;
+  else
+    {
+      struct autodetect_alias *alias;
+
+      /* Unsupported from_codeset or to_codeset. Check whether the caller
+	 requested autodetection.  */
+      for (alias = autodetect_list; alias != NULL; alias = alias->next)
+	if (strcmp (from_codeset, alias->name) == 0)
+	  {
+	    const char * const *encodings = alias->encodings_to_try;
+
+	    do
+	      {
+		retval = mem_iconveha (src, srclen,
+				       from_codeset, to_codeset, handler,
+				       resultp, lengthp);
+		if (!(retval < 0 && errno == EILSEQ))
+		  return retval;
+		encodings++;
+	      }
+	    while (*encodings != NULL);
+
+	    /* Return the last call's result.  */
+	    return -1;
+	  }
+
+      /* It wasn't an autodetection name.  */
+      errno = EINVAL;
+      return -1;
+    }
+}
+
+char *
+str_iconveha (const char *src,
+	      const char *from_codeset, const char *to_codeset,
+	      enum iconv_ilseq_handler handler)
+{
+  char *result = str_iconveh (src, from_codeset, to_codeset, handler);
+
+  if (result != NULL || errno != EINVAL)
+    return result;
+  else
+    {
+      struct autodetect_alias *alias;
+
+      /* Unsupported from_codeset or to_codeset. Check whether the caller
+	 requested autodetection.  */
+      for (alias = autodetect_list; alias != NULL; alias = alias->next)
+	if (strcmp (from_codeset, alias->name) == 0)
+	  {
+	    const char * const *encodings = alias->encodings_to_try;
+
+	    do
+	      {
+		result = str_iconveha (src, *encodings, to_codeset, handler);
+		if (!(result == NULL && errno == EILSEQ))
+		  return result;
+		encodings++;
+	      }
+	    while (*encodings != NULL);
+
+	    /* Return the last call's result.  */
+	    return NULL;
+	  }
+
+      /* It wasn't an autodetection name.  */
+      errno = EINVAL;
+      return NULL;
+    }
+}