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-rw-r--r--iconv/iconvconfig.c1165
1 files changed, 1165 insertions, 0 deletions
diff --git a/iconv/iconvconfig.c b/iconv/iconvconfig.c
new file mode 100644
index 0000000000..05b3c9d9a7
--- /dev/null
+++ b/iconv/iconvconfig.c
@@ -0,0 +1,1165 @@
+/* Generate fastloading iconv module configuration files.
+   Copyright (C) 2000, 2001 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Ulrich Drepper <drepper@redhat.com>, 2000.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Library General Public License as
+   published by the Free Software Foundation; either version 2 of the
+   License, or (at your option) any later version.
+
+   The GNU C Library 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
+   Library General Public License for more details.
+
+   You should have received a copy of the GNU Library General Public
+   License along with the GNU C Library; see the file COPYING.LIB.  If not,
+   write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.  */
+
+#include <argp.h>
+#include <assert.h>
+#include <error.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <libintl.h>
+#include <locale.h>
+#include <mcheck.h>
+#include <search.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdio_ext.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <sys/uio.h>
+
+#include "iconvconfig.h"
+
+/* Get libc version number.  */
+#include "../version.h"
+
+#define PACKAGE _libc_intl_domainname
+
+
+/* The hashing function we use.  */
+#include "../intl/hash-string.h"
+
+
+/* Types used.  */
+struct module
+{
+  char *fromname;
+  struct Strent *fromname_strent;
+  char *filename;
+  struct Strent *filename_strent;
+  const char *directory;
+  struct Strent *directory_strent;
+  struct module *next;
+  int cost;
+  struct Strent *toname_strent;
+  char toname[0];
+};
+
+struct alias
+{
+  char *fromname;
+  struct Strent *froment;
+  struct module *module;
+  struct Strent *toent;
+  char toname[0];
+};
+
+struct name
+{
+  const char *name;
+  struct Strent *strent;
+  int module_idx;
+  uint32_t hashval;
+};
+
+struct name_info
+{
+  const char *canonical_name;
+  struct Strent *canonical_strent;
+
+  struct module *from_internal;
+  struct module *to_internal;
+
+  struct other_conv_list
+  {
+    int dest_idx;
+    struct other_conv
+    {
+      gidx_t module_idx;
+      struct module *module;
+      struct other_conv *next;
+    } other_conv;
+    struct other_conv_list *next;
+  } *other_conv_list;
+};
+
+
+/* Name and version of program.  */
+static void print_version (FILE *stream, struct argp_state *state);
+void (*argp_program_version_hook) (FILE *, struct argp_state *) = print_version;
+
+#define OPT_VERBOSE	1000
+
+/* Definitions of arguments for argp functions.  */
+static const struct argp_option options[] =
+{
+  { "verbose", OPT_VERBOSE, NULL, 0, N_("print progress information") },
+  { NULL, 0, NULL, 0, NULL }
+};
+
+/* Short description of program.  */
+static const char doc[] = N_("\
+Create fastloading iconv module configuration file.");
+
+/* Strings for arguments in help texts.  */
+static const char args_doc[] = N_("[DIR...]");
+
+/* Prototype for option handler.  */
+static error_t parse_opt (int key, char *arg, struct argp_state *state);
+
+/* Function to print some extra text in the help message.  */
+static char *more_help (int key, const char *text, void *input);
+
+/* Data structure to communicate with argp functions.  */
+static struct argp argp =
+{
+  options, parse_opt, args_doc, doc, NULL, more_help
+};
+
+
+/* The function doing the actual work.  */
+static int handle_dir (const char *dir);
+
+/* Add all known builtin conversions and aliases.  */
+static void add_builtins (void);
+
+/* Create list of all aliases without circular aliases.  */
+static void get_aliases (void);
+
+/* Create list of all modules.  */
+static void get_modules (void);
+
+/* Get list of all the names and thereby indexing them.  */
+static void generate_name_list (void);
+
+/* Collect information about all the names.  */
+static void generate_name_info (void);
+
+/* Write the output file.  */
+static int write_output (void);
+
+
+/* Nonzero if verbose ouput is wanted.  */
+static int verbose;
+
+/* Search tree of the modules we know.  */
+static void *modules;
+
+/* Search tree of the aliases we know.  */
+static void *aliases;
+
+/* Search tree for name to index mapping.  */
+static void *names;
+
+/* Number of names we know about.  */
+static int nnames;
+
+/* List of all aliases.  */
+static struct alias **alias_list;
+static size_t nalias_list;
+static size_t nalias_list_max;
+
+/* List of all modules.  */
+static struct module **module_list;
+static size_t nmodule_list;
+static size_t nmodule_list_max;
+
+/* Names and information about them.  */
+static struct name_info *name_info;
+static size_t nname_info;
+
+/* Number of translations not from or to INTERNAL.  */
+static size_t nextra_modules;
+
+
+/* Names and aliases for the builtin transformations.  */
+static struct
+{
+  const char *from;
+  const char *to;
+} builtin_alias[] =
+  {
+#define BUILTIN_ALIAS(alias, real) \
+    { .from = alias, .to = real },
+#define BUILTIN_TRANSFORMATION(From, To, Cost, Name, Fct, MinF, MaxF, \
+			       MinT, MaxT)
+#include <gconv_builtin.h>
+  };
+#define nbuiltin_alias (sizeof (builtin_alias) / sizeof (builtin_alias[0]))
+
+static struct
+{
+  const char *from;
+  const char *to;
+  const char *module;
+  int cost;
+} builtin_trans[] =
+  {
+#define BUILTIN_ALIAS(alias, real)
+#define BUILTIN_TRANSFORMATION(From, To, Cost, Name, Fct, MinF, MaxF, \
+			       MinT, MaxT) \
+    { .from = From, .to = To, .module = Name, .cost = Cost },
+#include <gconv_builtin.h>
+  };
+#define nbuiltin_trans (sizeof (builtin_trans) / sizeof (builtin_trans[0]))
+
+
+/* Filename extension for the modules.  */
+#ifndef MODULE_EXT
+# define MODULE_EXT ".so"
+#endif
+static const char gconv_module_ext[] = MODULE_EXT;
+
+
+extern void *xmalloc (size_t n) __attribute__ ((__malloc__));
+extern void *xcalloc (size_t n, size_t m) __attribute__ ((__malloc__));
+extern void *xrealloc (void *p, size_t n);
+
+
+/* C string table handling.  */
+struct Strtab;
+struct Strent;
+
+/* Create new C string table object in memory.  */
+extern struct Strtab *strtabinit (void);
+
+/* Free resources allocated for C string table ST.  */
+extern void strtabfree (struct Strtab *st);
+
+/* Add string STR (length LEN is != 0) to C string table ST.  */
+extern struct Strent *strtabadd (struct Strtab *st, const char *str,
+				 size_t len);
+
+/* Finalize string table ST and store size in *SIZE and return a pointer.  */
+extern void *strtabfinalize (struct Strtab *st, size_t *size);
+
+/* Get offset in string table for string associated with SE.  */
+extern size_t strtaboffset (struct Strent *se);
+
+/* String table we construct.  */
+static struct Strtab *strtab;
+
+
+
+int
+main (int argc, char *argv[])
+{
+  int remaining;
+  int status = 0;
+  char *path;
+  char *tp;
+
+  /* Enable memory use testing.  */
+  mcheck_pedantic (NULL);
+
+  /* Set locale via LC_ALL.  */
+  setlocale (LC_ALL, "");
+
+  /* Set the text message domain.  */
+  textdomain (_libc_intl_domainname);
+
+  /* Parse and process arguments.  */
+  argp_parse (&argp, argc, argv, 0, &remaining, NULL);
+
+  /* Initialize the string table.  */
+  strtab = strtabinit ();
+
+  /* Handle all directories mentioned.  */
+  while (remaining < argc)
+    status |= handle_dir (argv[remaining++]);
+
+  /* In any case also handle the standard directory.  */
+  path = strdupa (GCONV_PATH);
+  tp = strtok (path, ":");
+  while (tp != NULL)
+    {
+      status |= handle_dir (tp);
+
+      tp = strtok (NULL, ":");
+    }
+
+  /* Add the builtin transformations and aliases without overwriting
+     anything.  */
+  add_builtins ();
+
+  /* Store aliases in an array.  */
+  get_aliases ();
+
+  /* Get list of all modules.  */
+  get_modules ();
+
+  /* Generate list of all the names we know to handle in some way.  */
+  generate_name_list ();
+
+  /* Now we know all the names we will handle, collect information
+     about them.  */
+  generate_name_info ();
+
+  /* Write the output file.  */
+  status = write_output ();
+
+  return status;
+}
+
+
+/* Handle program arguments.  */
+static error_t
+parse_opt (int key, char *arg, struct argp_state *state)
+{
+  switch (key)
+    {
+    case OPT_VERBOSE:
+      verbose = 1;
+      break;
+    default:
+      return ARGP_ERR_UNKNOWN;
+    }
+  return 0;
+}
+
+
+static char *
+more_help (int key, const char *text, void *input)
+{
+  switch (key)
+    {
+    case ARGP_KEY_HELP_EXTRA:
+      /* We print some extra information.  */
+      return strdup (gettext ("\
+Report bugs using the `glibcbug' script to <bugs@gnu.org>.\n"));
+    default:
+      break;
+    }
+  return (char *) text;
+}
+
+
+/* Print the version information.  */
+static void
+print_version (FILE *stream, struct argp_state *state)
+{
+  fprintf (stream, "iconvconfig (GNU %s) %s\n", PACKAGE, VERSION);
+  fprintf (stream, gettext ("\
+Copyright (C) %s Free Software Foundation, Inc.\n\
+This is free software; see the source for copying conditions.  There is NO\n\
+warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.\n\
+"), "2001");
+  fprintf (stream, gettext ("Written by %s.\n"), "Ulrich Drepper");
+}
+
+
+static int
+alias_compare (const void *p1, const void *p2)
+{
+  const struct alias *a1 = (const struct alias *) p1;
+  const struct alias *a2 = (const struct alias *) p2;
+
+  return strcmp (a1->fromname, a2->fromname);
+}
+
+
+static void
+new_alias (const char *fromname, size_t fromlen, const char *toname,
+	   size_t tolen)
+{
+  struct alias *newp;
+  void **inserted;
+
+  newp = (struct alias *) xmalloc (sizeof (struct alias) + fromlen + tolen);
+
+  newp->fromname = mempcpy (newp->toname, toname, tolen);
+  memcpy (newp->fromname, fromname, fromlen);
+  newp->module = NULL;
+
+  inserted = (void **) tsearch (newp, &aliases, alias_compare);
+  if (inserted == NULL)
+    error (EXIT_FAILURE, errno, gettext ("while inserting in search tree"));
+  if (*inserted != newp)
+    /* Something went wrong, free this entry.  */
+    free (newp);
+  else
+    {
+      newp->froment = strtabadd (strtab, newp->fromname, fromlen);
+      newp->toent = strtabadd (strtab, newp->toname, tolen);
+    }
+}
+
+
+/* Add new alias.  */
+static void
+add_alias (char *rp)
+{
+  /* We now expect two more string.  The strings are normalized
+     (converted to UPPER case) and strored in the alias database.  */
+  char *from;
+  char *to;
+  char *wp;
+
+  while (isspace (*rp))
+    ++rp;
+  from = wp = rp;
+  while (*rp != '\0' && !isspace (*rp))
+    *wp++ = toupper (*rp++);
+  if (*rp == '\0')
+    /* There is no `to' string on the line.  Ignore it.  */
+    return;
+  *wp++ = '\0';
+  to = ++rp;
+  while (isspace (*rp))
+    ++rp;
+  while (*rp != '\0' && !isspace (*rp))
+    *wp++ = toupper (*rp++);
+  if (to == wp)
+    /* No `to' string, ignore the line.  */
+    return;
+  *wp++ = '\0';
+
+  new_alias (from, to - from, to, wp - to);
+}
+
+
+static void
+append_alias (const void *nodep, VISIT value, int level)
+{
+  if (value != leaf && value != postorder)
+    return;
+
+  if (nalias_list_max == nalias_list)
+    {
+      nalias_list_max += 50;
+      alias_list = (struct alias **) xrealloc (alias_list,
+					       (nalias_list_max
+						* sizeof (struct alias *)));
+    }
+
+  alias_list[nalias_list++] = *(struct alias **) nodep;
+}
+
+
+static void
+get_aliases (void)
+{
+  twalk (aliases, append_alias);
+}
+
+
+static int
+module_compare (const void *p1, const void *p2)
+{
+  const struct module *m1 = (const struct module *) p1;
+  const struct module *m2 = (const struct module *) p2;
+  int result;
+
+  result = strcmp (m1->fromname, m2->fromname);
+  if (result == 0)
+    result = strcmp (m1->toname, m2->toname);
+
+  return result;
+}
+
+
+/* Create new module record.  */
+static void
+new_module (const char *fromname, size_t fromlen, const char *toname,
+	    size_t tolen, const char *directory,
+	    const char *filename, size_t filelen, int cost, size_t need_ext)
+{
+  struct module *new_module;
+  size_t dirlen = strlen (directory) + 1;
+  char *tmp;
+  void **inserted;
+
+  new_module = (struct module *) xmalloc (sizeof (struct module)
+					  + fromlen + tolen + filelen
+					  + need_ext);
+
+  new_module->fromname = mempcpy (new_module->toname, toname, tolen);
+
+  new_module->filename = mempcpy (new_module->fromname, fromname, fromlen);
+
+  new_module->cost = cost;
+  new_module->next = NULL;
+
+  tmp = mempcpy (new_module->filename, filename, filelen);
+  if (need_ext)
+    {
+      memcpy (tmp - 1, gconv_module_ext, sizeof (gconv_module_ext));
+      filelen += sizeof (gconv_module_ext) - 1;
+    }
+  new_module->directory = directory;
+
+  /* Now insert the new module data structure in our search tree.  */
+  inserted = (void **) tsearch (new_module, &modules, module_compare);
+  if (inserted == NULL)
+    error (EXIT_FAILURE, errno, "while inserting in search tree");
+  if (*inserted != new_module)
+    free (new_module);
+  else
+    {
+      new_module->fromname_strent = strtabadd (strtab, new_module->fromname,
+					       fromlen);
+      new_module->toname_strent = strtabadd (strtab, new_module->toname,
+					     tolen);
+      new_module->filename_strent = strtabadd (strtab, new_module->filename,
+					       filelen);
+      new_module->directory_strent = strtabadd (strtab, directory, dirlen);
+    }
+}
+
+
+/* Add new module.  */
+static void
+internal_function
+add_module (char *rp, const char *directory)
+{
+  /* We expect now
+     1. `from' name
+     2. `to' name
+     3. filename of the module
+     4. an optional cost value
+  */
+  char *from;
+  char *to;
+  char *module;
+  char *wp;
+  int need_ext;
+  int cost;
+
+  while (isspace (*rp))
+    ++rp;
+  from = rp;
+  while (*rp != '\0' && !isspace (*rp))
+    {
+      *rp = toupper (*rp);
+      ++rp;
+    }
+  if (*rp == '\0')
+    return;
+  *rp++ = '\0';
+  to = wp = rp;
+  while (isspace (*rp))
+    ++rp;
+  while (*rp != '\0' && !isspace (*rp))
+    *wp++ = toupper (*rp++);
+  if (*rp == '\0')
+    return;
+  *wp++ = '\0';
+  do
+    ++rp;
+  while (isspace (*rp));
+  module = wp;
+  while (*rp != '\0' && !isspace (*rp))
+    *wp++ = *rp++;
+  if (*rp == '\0')
+    {
+      /* There is no cost, use one by default.  */
+      *wp++ = '\0';
+      cost = 1;
+    }
+  else
+    {
+      /* There might be a cost value.  */
+      char *endp;
+
+      *wp++ = '\0';
+      cost = strtol (rp, &endp, 10);
+      if (rp == endp || cost < 1)
+	/* No useful information.  */
+	cost = 1;
+    }
+
+  if (module[0] == '\0')
+    /* No module name given.  */
+    return;
+
+  /* See whether we must add the ending.  */
+  need_ext = 0;
+  if (wp - module < sizeof (gconv_module_ext)
+      || memcmp (wp - sizeof (gconv_module_ext), gconv_module_ext,
+		 sizeof (gconv_module_ext)) != 0)
+    /* We must add the module extension.  */
+    need_ext = sizeof (gconv_module_ext) - 1;
+
+  assert (strlen (from) + 1 == to - from);
+  assert (strlen (to) + 1 == module - to);
+  assert (strlen (module) + 1 == wp - module);
+
+  new_module (from, to - from, to, module - to, directory, module, wp - module,
+	      cost, need_ext);
+}
+
+
+/* Read the config file and add the data for this directory to that.  */
+static int
+handle_dir (const char *dir)
+{
+  char *infile;
+  FILE *fp;
+  char *line = NULL;
+  size_t linelen = 0;
+  size_t dirlen = strlen (dir);
+
+  if (dir[dirlen - 1] != '/')
+    {
+      char *newp = (char *) xmalloc (dirlen + 2);
+      dir = memcpy (newp, dir, dirlen);
+      newp[dirlen++] = '/';
+      newp[dirlen] = '\0';
+    }
+
+  infile = (char *) alloca (dirlen + sizeof "gconv-modules");
+  strcpy (mempcpy (infile, dir, dirlen), "gconv-modules");
+
+  fp = fopen (infile, "r");
+  if (fp == NULL)
+    {
+      error (0, errno, "cannot open `%s'", infile);
+      return 1;
+    }
+
+  /* No threads present.  */
+  __fsetlocking (fp, FSETLOCKING_BYCALLER);
+
+  while (!feof_unlocked (fp))
+    {
+      char *rp, *endp, *word;
+      ssize_t n = __getdelim (&line, &linelen, '\n', fp);
+
+      if (n < 0)
+	/* An error occurred.  */
+	break;
+
+      rp = line;
+      /* Terminate the line (excluding comments or newline) with a NUL
+	 byte to simplify the following code.  */
+      endp = strchr (rp, '#');
+      if (endp != NULL)
+	*endp = '\0';
+      else
+	if (rp[n - 1] == '\n')
+	  rp[n - 1] = '\0';
+
+      while (isspace (*rp))
+	++rp;
+
+      /* If this is an empty line go on with the next one.  */
+      if (rp == endp)
+	continue;
+
+      word = rp;
+      while (*rp != '\0' && !isspace (*rp))
+	++rp;
+
+      if (rp - word == sizeof ("alias") - 1
+	  && memcmp (word, "alias", sizeof ("alias") - 1) == 0)
+	add_alias (rp);
+      else if (rp - word == sizeof ("module") - 1
+	       && memcmp (word, "module", sizeof ("module") - 1) == 0)
+	add_module (rp, dir);
+      /* else */
+	/* Otherwise ignore the line.  */
+    }
+
+  free (line);
+
+  fclose (fp);
+
+  return 0;
+}
+
+
+static void
+append_module (const void *nodep, VISIT value, int level)
+{
+  struct module *mo;
+
+  if (value != leaf && value != postorder)
+    return;
+
+  mo = *(struct module **) nodep;
+
+  if (nmodule_list > 0
+      && strcmp (module_list[nmodule_list - 1]->fromname, mo->fromname) == 0)
+    {
+      /* Same name.  */
+      mo->next = module_list[nmodule_list - 1];
+      module_list[nmodule_list - 1] = mo;
+
+      return;
+    }
+
+  if (nmodule_list_max == nmodule_list)
+    {
+      nmodule_list_max += 50;
+      module_list = (struct module **) xrealloc (module_list,
+						 (nmodule_list_max
+						  * sizeof (struct module *)));
+    }
+
+  module_list[nmodule_list++] = mo;
+}
+
+
+static void
+get_modules (void)
+{
+  twalk (modules, append_module);
+}
+
+
+static void
+add_builtins (void)
+{
+  size_t cnt;
+
+  /* Add all aliases.  */
+  for (cnt = 0; cnt < nbuiltin_alias; ++cnt)
+    new_alias (builtin_alias[cnt].from,
+	       strlen (builtin_alias[cnt].from) + 1,
+	       builtin_alias[cnt].to,
+	       strlen (builtin_alias[cnt].to) + 1);
+
+  /* add the builtin transformations.  */
+  for (cnt = 0; cnt < nbuiltin_trans; ++cnt)
+    new_module (builtin_trans[cnt].from,
+		strlen (builtin_trans[cnt].from) + 1,
+		builtin_trans[cnt].to,
+		strlen (builtin_trans[cnt].to) + 1,
+		"", builtin_trans[cnt].module,
+		strlen (builtin_trans[cnt].module) + 1,
+		builtin_trans[cnt].cost, 0);
+}
+
+
+static int
+name_compare (const void *p1, const void *p2)
+{
+  const struct name *n1 = (const struct name *) p1;
+  const struct name *n2 = (const struct name *) p2;
+
+  return strcmp (n1->name, n2->name);
+}
+
+
+static struct name *
+new_name (const char *str, struct Strent *strent)
+{
+  struct name *newp = (struct name *) xmalloc (sizeof (struct name));
+
+  newp->name = str;
+  newp->strent = strent;
+  newp->module_idx = -1;
+  newp->hashval = hash_string (str);
+
+  ++nnames;
+
+  return newp;
+}
+
+
+static void
+generate_name_list (void)
+{
+  size_t i;
+
+  for (i = 0; i < nmodule_list; ++i)
+    {
+      struct module *runp;
+
+      if (strcmp (module_list[i]->fromname, "INTERNAL") != 0)
+	tsearch (new_name (module_list[i]->fromname,
+			   module_list[i]->fromname_strent),
+		 &names, name_compare);
+
+      for (runp = module_list[i]; runp != NULL; runp = runp->next)
+	if (strcmp (runp->toname, "INTERNAL") != 0)
+	  tsearch (new_name (runp->toname, runp->toname_strent),
+		   &names, name_compare);
+    }
+}
+
+
+static int
+name_to_module_idx (const char *name, int add)
+{
+  struct name **res;
+  struct name fake_name = { .name = name };
+  int idx;
+
+  res = (struct name **) tfind (&fake_name, &names, name_compare);
+  if (res == NULL)
+    abort ();
+
+  idx = (*res)->module_idx;
+  if (idx == -1 && add)
+    /* No module index assigned yet.  */
+    idx = (*res)->module_idx = nname_info++;
+
+  return idx;
+}
+
+
+static void
+generate_name_info (void)
+{
+  size_t i;
+
+  name_info = (struct name_info *) xcalloc (nmodule_list,
+					    sizeof (struct name_info));
+
+  for (i = 0; i < nmodule_list; ++i)
+    {
+      struct module *runp;
+
+      for (runp = module_list[i]; runp != NULL; runp = runp->next)
+	if (strcmp (runp->fromname, "INTERNAL") == 0)
+	  {
+	    int idx = name_to_module_idx (runp->toname, 1);
+	    name_info[idx].from_internal = runp;
+	    assert (name_info[idx].canonical_name == NULL
+		    || strcmp (name_info[idx].canonical_name,
+			       runp->toname) == 0);
+	    name_info[idx].canonical_name = runp->toname;
+	    name_info[idx].canonical_strent = runp->toname_strent;
+	  }
+	else if (strcmp (runp->toname, "INTERNAL") == 0)
+	  {
+	    int idx = name_to_module_idx (runp->fromname, 1);
+	    name_info[idx].to_internal = runp;
+	    assert (name_info[idx].canonical_name == NULL
+		    || strcmp (name_info[idx].canonical_name,
+			       runp->fromname) == 0);
+	    name_info[idx].canonical_name = runp->fromname;
+	    name_info[idx].canonical_strent = runp->fromname_strent;
+	  }
+	else
+	  {
+	    /* This is a transformation not to or from the INTERNAL
+	       encoding.  */
+	    int from_idx = name_to_module_idx (runp->fromname, 1);
+	    int to_idx = name_to_module_idx (runp->toname, 1);
+	    struct other_conv_list *newp;
+
+	    newp = (struct other_conv_list *)
+	      xmalloc (sizeof (struct other_conv_list));
+	    newp->other_conv.module_idx = to_idx;
+	    newp->other_conv.module = runp;
+	    newp->other_conv.next = NULL; /* XXX Allow multiple module sequence */
+	    newp->dest_idx = to_idx;
+	    newp->next = name_info[from_idx].other_conv_list;
+	    name_info[from_idx].other_conv_list = newp;
+	    assert (name_info[from_idx].canonical_name == NULL
+		    || strcmp (name_info[from_idx].canonical_name,
+			       runp->fromname) == 0);
+	    name_info[from_idx].canonical_name = runp->fromname;
+	    name_info[from_idx].canonical_strent = runp->fromname_strent;
+
+	    ++nextra_modules;
+	  }
+    }
+
+  /* Now add the module index information for all the aliases.  */
+  for (i = 0; i < nalias_list; ++i)
+    {
+      struct name fake_name = { .name = alias_list[i]->toname };
+      struct name **tonamep;
+
+      tonamep = (struct name **) tfind (&fake_name, &names, name_compare);
+      if (tonamep != NULL)
+	{
+	  struct name *newp = new_name (alias_list[i]->fromname,
+					alias_list[i]->froment);
+	  newp->module_idx = (*tonamep)->module_idx;
+	  tsearch (newp, &names, name_compare);
+	}
+    }
+}
+
+
+static int
+is_prime (unsigned long int candidate)
+{
+  /* No even number and none less than 10 will be passed here.  */
+  unsigned long int divn = 3;
+  unsigned long int sq = divn * divn;
+
+  while (sq < candidate && candidate % divn != 0)
+    {
+      ++divn;
+      sq += 4 * divn;
+      ++divn;
+    }
+
+  return candidate % divn != 0;
+}
+
+
+static uint32_t
+next_prime (uint32_t seed)
+{
+  /* Make it definitely odd.  */
+  seed |= 1;
+
+  while (!is_prime (seed))
+    seed += 2;
+
+  return seed;
+}
+
+
+/* Format of the output file.
+
+   Offset   Length       Description
+   0000     4            Magic header bytes
+   0004     4            Offset of string table (stoff)
+   0008     4            Offset of name hashing table (hoff)
+   000C     4            Hashing table size (hsize)
+   0010     4            Offset of module table (moff)
+   0014     4            Offset of other conversion module table (ooff)
+
+   stoff    ???          String table
+
+   hoff     8*hsize      Array of tuples
+                            string table offset
+                            module index
+
+   moff     ???          Array of tuples
+                            canonical name offset
+                            from-internal module dir name offset
+                            from-internal module name off
+                            to-internal module dir name offset
+                            to-internal module name offset
+                            offset into other conversion table
+
+   ooff     ???          Sequence of words
+                            name offset
+                            one or more of tuple
+                              canonical name offset
+                              module dir name offset
+                              module name offset
+                            (following last entry canocical name offset is 0)
+*/
+static int
+write_output (void)
+{
+  int fd;
+  char *string_table;
+  size_t string_table_size;
+  struct gconvcache_header header;
+  struct hash_entry *hash_table;
+  size_t hash_size;
+  struct module_entry *module_table;
+  char *extra_table;
+  char *cur_extra_table;
+  size_t n;
+  int idx;
+  struct iovec iov[6];
+  static const gidx_t null_word;
+  size_t total;
+
+  /* Function to insert the names.  */
+  void name_insert (const void *nodep, VISIT value, int level)
+    {
+      struct name *name;
+      unsigned int idx;
+      unsigned int hval2;
+
+      if (value != leaf && value != postorder)
+	return;
+
+      name = *(struct name **) nodep;
+      idx = name->hashval % hash_size;
+      hval2 = 1 + name->hashval % (hash_size - 2);
+
+      while (hash_table[idx].string_offset != 0)
+	if ((idx += hval2) >= hash_size)
+	  idx -= hash_size;
+
+      hash_table[idx].string_offset = strtaboffset (name->strent);
+
+      assert (name->module_idx != -1);
+      hash_table[idx].module_idx = name->module_idx;
+    }
+
+  /* Open the output file.  */
+  fd = open (GCONV_MODULES_CACHE, O_TRUNC | O_CREAT | O_RDWR, 0644);
+  if (fd == -1)
+    return 1;
+
+  /* Create the string table.  */
+  string_table = strtabfinalize (strtab, &string_table_size);
+
+  /* Create the hashing table.  We know how many strings we have.
+     Creating a perfect hash table is not reasonable here.  Therefore
+     we use open hashing and a table size which is the next prime 40%
+     larger than the number of strings.  */
+  hash_size = next_prime (nnames * 1.4);
+  hash_table = (struct hash_entry *) xcalloc (hash_size,
+					      sizeof (struct hash_entry));
+  /* Fill the hash table.  */
+  twalk (names, name_insert);
+
+  /* Create the section for the module list.  */
+  module_table = (struct module_entry *) xcalloc (sizeof (struct module_entry),
+						  nname_info);
+
+  /* Allocate memory for the non-INTERNAL conversions.  The allocated
+     memory can be more than is actually needed.  */
+  extra_table = (char *) xcalloc (sizeof (struct extra_entry)
+				  + sizeof (gidx_t)
+				  + sizeof (struct extra_entry_module),
+				  nextra_modules);
+  cur_extra_table = extra_table;
+
+  /* Fill in the module information.  */
+  for (n = 0; n < nname_info; ++n)
+    {
+      module_table[n].canonname_offset =
+	strtaboffset (name_info[n].canonical_strent);
+
+      if (name_info[n].from_internal == NULL)
+	{
+	  module_table[n].fromdir_offset = 0;
+	  module_table[n].fromname_offset = 0;
+	}
+      else
+	{
+	  module_table[n].fromdir_offset =
+	    strtaboffset (name_info[n].from_internal->directory_strent);
+	  module_table[n].fromname_offset =
+	    strtaboffset (name_info[n].from_internal->filename_strent);
+	}
+
+      if (name_info[n].to_internal == NULL)
+	{
+	  module_table[n].todir_offset = 0;
+	  module_table[n].toname_offset = 0;
+	}
+      else
+	{
+	  module_table[n].todir_offset =
+	    strtaboffset (name_info[n].to_internal->directory_strent);
+	  module_table[n].toname_offset =
+	    strtaboffset (name_info[n].to_internal->filename_strent);
+	}
+
+      if (name_info[n].other_conv_list != NULL)
+	{
+	  struct other_conv_list *other = name_info[n].other_conv_list;
+
+	  /* Store the reference.  We add 1 to distinguish the entry
+	     at offset zero from the case where no extra modules are
+	     available.  The file reader has to account for the
+	     offset.  */
+	  module_table[n].extra_offset = 1 + cur_extra_table - extra_table;
+
+	  do
+	    {
+	      struct other_conv *runp;
+	      struct extra_entry *extra;
+
+	      /* Allocate new entry.  */
+	      extra = (struct extra_entry *) cur_extra_table;
+	      cur_extra_table += sizeof (struct extra_entry);
+	      extra->module_cnt = 0;
+
+	      runp = &other->other_conv;
+	      do
+		{
+		  cur_extra_table += sizeof (struct extra_entry_module);
+		  extra->module[extra->module_cnt].outname_offset =
+		    runp->next == NULL
+		    ? other->dest_idx : runp->next->module_idx;
+		  extra->module[extra->module_cnt].dir_offset =
+		    strtaboffset (runp->module->directory_strent);
+		  extra->module[extra->module_cnt].name_offset =
+		    strtaboffset (runp->module->filename_strent);
+		  ++extra->module_cnt;
+
+		  runp = runp->next;
+		}
+	      while (runp != NULL);
+
+	      other = other->next;
+	    }
+	  while (other != NULL);
+
+	  /* Final module_cnt is zero.  */
+	  *((gidx_t *) cur_extra_table) = 0;
+	  cur_extra_table += sizeof (gidx_t);
+	}
+    }
+
+  header.magic = GCONVCACHE_MAGIC;
+
+  iov[0].iov_base = &header;
+  iov[0].iov_len = sizeof (struct gconvcache_header);
+  total = iov[0].iov_len;
+
+  header.string_offset = total;
+  iov[1].iov_base = string_table;
+  iov[1].iov_len = string_table_size;
+  total += iov[1].iov_len;
+
+  idx = 2;
+  if ((string_table_size & (sizeof (gidx_t) - 1)) != 0)
+    {
+      iov[2].iov_base = (void *) &null_word;
+      iov[2].iov_len = (sizeof (gidx_t)
+			- (string_table_size & (sizeof (gidx_t) - 1)));
+      total += iov[2].iov_len;
+      ++idx;
+    }
+
+  header.hash_offset = total;
+  header.hash_size = hash_size;
+  iov[idx].iov_base = hash_table;
+  iov[idx].iov_len = hash_size * sizeof (struct hash_entry);
+  total += iov[idx].iov_len;
+  ++idx;
+
+  header.module_offset = total;
+  iov[idx].iov_base = module_table;
+  iov[idx].iov_len = nname_info * sizeof (struct module_entry);
+  total += iov[idx].iov_len;
+  ++idx;
+
+  assert (cur_extra_table - extra_table
+	  <= ((sizeof (struct extra_entry) + sizeof (gidx_t)
+	       + sizeof (struct extra_entry_module))
+	      * nextra_modules));
+  header.otherconv_offset = total;
+  iov[idx].iov_base = extra_table;
+  iov[idx].iov_len = cur_extra_table - extra_table;
+  total += iov[idx].iov_len;
+  ++idx;
+
+  if (TEMP_FAILURE_RETRY (writev (fd, iov, idx)) != total)
+    {
+      int save_errno = errno;
+      close (fd);
+      unlink (GCONV_MODULES_CACHE);
+      error (EXIT_FAILURE, save_errno, gettext ("cannot write output file"));
+    }
+
+  close (fd);
+
+  return 0;
+}