general.c

android-w.song.android.widget

{
  if (string == 0 || *string == '\0')
    return (0);

  if (ABSPATH(string))
    return (1);

  if (string[0] == '.' && PATHSEP(string[1]))	/* . and ./ */
    return (1);

  if (string[0] == '.' && string[1] == '.' && PATHSEP(string[2]))	/* .. and ../ */
    return (1);

  return (0);
}

/* Return 1 if STRING is an absolute program name; it is absolute if it
   contains any slashes.  This is used to decide whether or not to look
   up through $PATH. */
int
absolute_program (string)
     const char *string;
{
  return ((char *)mbschr (string, '/') != (char *)NULL);
}

/* **************************************************************** */
/*								    */
/*		    Functions to manipulate pathnames		    */
/*								    */
/* **************************************************************** */

/* Turn STRING (a pathname) into an absolute pathname, assuming that
   DOT_PATH contains the symbolic location of `.'.  This always
   returns a new string, even if STRING was an absolute pathname to
   begin with. */
char *
make_absolute (string, dot_path)
     char *string, *dot_path;
{
  char *result;

  if (dot_path == 0 || ABSPATH(string))
#ifdef __CYGWIN__
    {
      char pathbuf[PATH_MAX + 1];

      cygwin_conv_to_full_posix_path (string, pathbuf);
      result = savestring (pathbuf);
    }
#else
    result = savestring (string);
#endif
  else
    result = sh_makepath (dot_path, string, 0);

  return (result);
}

/* Return the `basename' of the pathname in STRING (the stuff after the
   last '/').  If STRING is `/', just return it. */
char *
base_pathname (string)
     char *string;
{
  char *p;

#if 0
  if (absolute_pathname (string) == 0)
    return (string);
#endif

  if (string[0] == '/' && string[1] == 0)
    return (string);

  p = (char *)strrchr (string, '/');
  return (p ? ++p : string);
}

/* Return the full pathname of FILE.  Easy.  Filenames that begin
   with a '/' are returned as themselves.  Other filenames have
   the current working directory prepended.  A new string is
   returned in either case. */
char *
full_pathname (file)
     char *file;
{
  char *ret;

  file = (*file == '~') ? bash_tilde_expand (file, 0) : savestring (file);

  if (ABSPATH(file))
    return (file);

  ret = sh_makepath ((char *)NULL, file, (MP_DOCWD|MP_RMDOT));
  free (file);

  return (ret);
}

/* A slightly related function.  Get the prettiest name of this
   directory possible. */
static char tdir[PATH_MAX];

/* Return a pretty pathname.  If the first part of the pathname is
   the same as $HOME, then replace that with `~'.  */
char *
polite_directory_format (name)
     char *name;
{
  char *home;
  int l;

  home = get_string_value ("HOME");
  l = home ? strlen (home) : 0;
  if (l > 1 && strncmp (home, name, l) == 0 && (!name[l] || name[l] == '/'))
    {
      strncpy (tdir + 1, name + l, sizeof(tdir) - 2);
      tdir[0] = '~';
      tdir[sizeof(tdir) - 1] = '\0';
      return (tdir);
    }
  else
    return (name);
}

/* Trim NAME.  If NAME begins with `~/', skip over tilde prefix.  Trim to
   keep any tilde prefix and PROMPT_DIRTRIM trailing directory components
   and replace the intervening characters with `...' */
char *
trim_pathname (name, maxlen)
     char *name;
     int maxlen;
{
  int nlen, ndirs;
  intmax_t nskip;
  char *nbeg, *nend, *ntail, *v;

  if (name == 0 || (nlen = strlen (name)) == 0)
    return name;
  nend = name + nlen;

  v = get_string_value ("PROMPT_DIRTRIM");
  if (v == 0 || *v == 0)
    return name;
  if (legal_number (v, &nskip) == 0 || nskip <= 0)
    return name;

  /* Skip over tilde prefix */
  nbeg = name;
  if (name[0] == '~')
    for (nbeg = name; *nbeg; nbeg++)
      if (*nbeg == '/')
	{
	  nbeg++;
	  break;
	}
  if (*nbeg == 0)
    return name;

  for (ndirs = 0, ntail = nbeg; *ntail; ntail++)
    if (*ntail == '/')
      ndirs++;
  if (ndirs < nskip)
    return name;

  for (ntail = (*nend == '/') ? nend : nend - 1; ntail > nbeg; ntail--)
    {
      if (*ntail == '/')
	nskip--;
      if (nskip == 0)
	break;
    }
  if (ntail == nbeg)
    return name;

  /* Now we want to return name[0..nbeg]+"..."+ntail, modifying name in place */
  nlen = ntail - nbeg;
  if (nlen <= 3)
    return name;

  *nbeg++ = '.';
  *nbeg++ = '.';
  *nbeg++ = '.';

  nlen = nend - ntail;
  memcpy (nbeg, ntail, nlen);
  nbeg[nlen] = '\0';

  return name;
}

/* Given a string containing units of information separated by colons,
   return the next one pointed to by (P_INDEX), or NULL if there are no more.
   Advance (P_INDEX) to the character after the colon. */
char *
extract_colon_unit (string, p_index)
     char *string;
     int *p_index;
{
  int i, start, len;
  char *value;

  if (string == 0)
    return (string);

  len = strlen (string);
  if (*p_index >= len)
    return ((char *)NULL);

  i = *p_index;

  /* Each call to this routine leaves the index pointing at a colon if
     there is more to the path.  If I is > 0, then increment past the
     `:'.  If I is 0, then the path has a leading colon.  Trailing colons
     are handled OK by the `else' part of the if statement; an empty
     string is returned in that case. */
  if (i && string[i] == ':')
    i++;

  for (start = i; string[i] && string[i] != ':'; i++)
    ;

  *p_index = i;

  if (i == start)
    {
      if (string[i])
	(*p_index)++;
      /* Return "" in the case of a trailing `:'. */
      value = (char *)xmalloc (1);
      value[0] = '\0';
    }
  else
    value = substring (string, start, i);

  return (value);
}

/* **************************************************************** */
/*								    */
/*		    Tilde Initialization and Expansion		    */
/*								    */
/* **************************************************************** */

#if defined (PUSHD_AND_POPD)
extern char *get_dirstack_from_string __P((char *));
#endif

static char **bash_tilde_prefixes;
static char **bash_tilde_prefixes2;
static char **bash_tilde_suffixes;
static char **bash_tilde_suffixes2;

/* If tilde_expand hasn't been able to expand the text, perhaps it
   is a special shell expansion.  This function is installed as the
   tilde_expansion_preexpansion_hook.  It knows how to expand ~- and ~+.
   If PUSHD_AND_POPD is defined, ~[+-]N expands to directories from the
   directory stack. */
static char *
bash_special_tilde_expansions (text)
     char *text;
{
  char *result;

  result = (char *)NULL;

  if (text[0] == '+' && text[1] == '\0')
    result = get_string_value ("PWD");
  else if (text[0] == '-' && text[1] == '\0')
    result = get_string_value ("OLDPWD");
#if defined (PUSHD_AND_POPD)
  else if (DIGIT (*text) || ((*text == '+' || *text == '-') && DIGIT (text[1])))
    result = get_dirstack_from_string (text);
#endif

  return (result ? savestring (result) : (char *)NULL);
}

/* Initialize the tilde expander.  In Bash, we handle `~-' and `~+', as
   well as handling special tilde prefixes; `:~" and `=~' are indications
   that we should do tilde expansion. */
void
tilde_initialize ()
{
  static int times_called = 0;

  /* Tell the tilde expander that we want a crack first. */
  tilde_expansion_preexpansion_hook = bash_special_tilde_expansions;

  /* Tell the tilde expander about special strings which start a tilde
     expansion, and the special strings that end one.  Only do this once.
     tilde_initialize () is called from within bashline_reinitialize (). */
  if (times_called++ == 0)
    {
      bash_tilde_prefixes = strvec_create (3);
      bash_tilde_prefixes[0] = "=~";
      bash_tilde_prefixes[1] = ":~";
      bash_tilde_prefixes[2] = (char *)NULL;

      bash_tilde_prefixes2 = strvec_create (2);
      bash_tilde_prefixes2[0] = ":~";
      bash_tilde_prefixes2[1] = (char *)NULL;

      tilde_additional_prefixes = bash_tilde_prefixes;

      bash_tilde_suffixes = strvec_create (3);
      bash_tilde_suffixes[0] = ":";
      bash_tilde_suffixes[1] = "=~";	/* XXX - ?? */
      bash_tilde_suffixes[2] = (char *)NULL;

      tilde_additional_suffixes = bash_tilde_suffixes;

      bash_tilde_suffixes2 = strvec_create (2);
      bash_tilde_suffixes2[0] = ":";
      bash_tilde_suffixes2[1] = (char *)NULL;
    }
}

/* POSIX.2, 3.6.1:  A tilde-prefix consists of an unquoted tilde character
   at the beginning of the word, followed by all of the characters preceding
   the first unquoted slash in the word, or all the characters in the word
   if there is no slash...If none of the characters in the tilde-prefix are
   quoted, the characters in the tilde-prefix following the tilde shell be
   treated as a possible login name. */

#define TILDE_END(c)	((c) == '\0' || (c) == '/' || (c) == ':')

static int
unquoted_tilde_word (s)
     const char *s;
{
  const char *r;

  for (r = s; TILDE_END(*r) == 0; r++)
    {
      switch (*r)
	{
	case '\\':
	case '\'':
	case '"':
	  return 0;
	}
    }
  return 1;
}

/* Find the end of the tilde-prefix starting at S, and return the tilde
   prefix in newly-allocated memory.  Return the length of the string in
   *LENP.  FLAGS tells whether or not we're in an assignment context --
   if so, `:' delimits the end of the tilde prefix as well. */
char *
bash_tilde_find_word (s, flags, lenp)
     const char *s;
     int flags, *lenp;
{
  const char *r;
  char *ret;
  int l;

  for (r = s; *r && *r != '/'; r++)
    {
      /* Short-circuit immediately if we see a quote character.  Even though
	 POSIX says that `the first unquoted slash' (or `:') terminates the
	 tilde-prefix, in practice, any quoted portion of the tilde prefix
	 will cause it to not be expanded. */
      if (*r == '\\' || *r == '\'' || *r == '"')  
	{
	  ret = savestring (s);
	  if (lenp)
	    *lenp = 0;
	  return ret;
	}
      else if (flags && *r == ':')
	break;
    }
  l = r - s;
  ret = xmalloc (l + 1);
  strncpy (ret, s, l);
  ret[l] = '\0';
  if (lenp)
    *lenp = l;
  return ret;
}
    
/* Tilde-expand S by running it through the tilde expansion library.
   ASSIGN_P is 1 if this is a variable assignment, so the alternate
   tilde prefixes should be enabled (`=~' and `:~', see above).  If
   ASSIGN_P is 2, we are expanding the rhs of an assignment statement,
   so `=~' is not valid. */
char *
bash_tilde_expand (s, assign_p)
     const char *s;
     int assign_p;
{
  int old_immed, old_term, r;
  char *ret;

  old_immed = interrupt_immediately;
  old_term = terminate_immediately;
  interrupt_immediately = terminate_immediately = 1;

  tilde_additional_prefixes = assign_p == 0 ? (char **)0
  					    : (assign_p == 2 ? bash_tilde_prefixes2 : bash_tilde_prefixes);
  if (assign_p == 2)
    tilde_additional_suffixes = bash_tilde_suffixes2;

  r = (*s == '~') ? unquoted_tilde_word (s) : 1;
  ret = r ? tilde_expand (s) : savestring (s);
  interrupt_immediately = old_immed;
  terminate_immediately = old_term;
  return (ret);
}

/* **************************************************************** */
/*								    */
/*	  Functions to manipulate and search the group list	    */
/*								    */
/* **************************************************************** */

static int ngroups, maxgroups;

/* The set of groups that this user is a member of. */
static GETGROUPS_T *group_array = (GETGROUPS_T *)NULL;

#if !defined (NOGROUP)
#  define NOGROUP (gid_t) -1
#endif

static void
initialize_group_array ()
{
  register int i;

  if (maxgroups == 0)
    maxgroups = getmaxgroups ();

  ngroups = 0;
  group_array = (GETGROUPS_T *)xrealloc (group_array, maxgroups * sizeof (GETGROUPS_T));

#if defined (HAVE_GETGROUPS)
  ngroups = getgroups (maxgroups, group_array);
#endif

  /* If getgroups returns nothing, or the OS does not support getgroups(),
     make sure the groups array includes at least the current gid. */
  if (ngroups == 0)
    {
      group_array[0] = current_user.gid;
      ngroups = 1;
    }

  /* If the primary group is not in the groups array, add it as group_array[0]
     and shuffle everything else up 1, if there's room. */
  for (i = 0; i < ngroups; i++)
    if (current_user.gid == (gid_t)group_array[i])
      break;
  if (i == ngroups && ngroups < maxgroups)
    {
      for (i = ngroups; i > 0; i--)
	group_array[i] = group_array[i - 1];
      group_array[0] = current_user.gid;
      ngroups++;
    }

  /* If the primary group is not group_array[0], swap group_array[0] and
     whatever the current group is.  The vast majority of systems should
     not need this; a notable exception is Linux. */
  if (group_array[0] != current_user.gid)
    {
      for (i = 0; i < ngroups; i++)
	if (group_array[i] == current_user.gid)
	  break;
      if (i < ngroups)
	{
	  group_array[i] = group_array[0];
	  group_array[0] = current_user.gid;
	}
    }
}

/* Return non-zero if GID is one that we have in our groups list. */
int
#if defined (__STDC__) || defined ( _MINIX)
group_member (gid_t gid)
#else
group_member (gid)
     gid_t gid;
#endif /* !__STDC__ && !_MINIX */
{
#if defined (HAVE_GETGROUPS)
  register int i;
#endif

  /* Short-circuit if possible, maybe saving a call to getgroups(). */
  if (gid == current_user.gid || gid == current_user.egid)
    return (1);

#if defined (HAVE_GETGROUPS)
  if (ngroups == 0)
    initialize_group_array ();

  /* In case of error, the user loses. */
  if (ngroups <= 0)
    return (0);

  /* Search through the list looking for GID. */
  for (i = 0; i < ngroups; i++)
    if (gid == (gid_t)group_array[i])
      return (1);
#endif

  return (0);
}

char **
get_group_list (ngp)
     int *ngp;
{
  static char **group_vector = (char **)NULL;
  register int i;

  if (group_vector)
    {
      if (ngp)
	*ngp = ngroups;
      return group_vector;
    }

  if (ngroups == 0)
    initialize_group_array ();

  if (ngroups <= 0)
    {
      if (ngp)
	*ngp = 0;
      return (char **)NULL;
    }

  group_vector = strvec_create (ngroups);
  for (i = 0; i < ngroups; i++)
    group_vector[i] = itos (group_array[i]);

  if (ngp)
    *ngp = ngroups;
  return group_vector;
}

int *
get_group_array (ngp)
     int *ngp;
{
  int i;
  static int *group_iarray = (int *)NULL;

  if (group_iarray)
    {
      if (ngp)
	*ngp = ngroups;
      return (group_iarray);
    }

  if (ngroups == 0)
    initialize_group_array ();    

  if (ngroups <= 0)
    {
      if (ngp)
	*ngp = 0;
      return (int *)NULL;
    }

  group_iarray = (int *)xmalloc (ngroups * sizeof (int));
  for (i = 0; i < ngroups; i++)
    group_iarray[i] = (int)group_array[i];

  if (ngp)
    *ngp = ngroups;
  return group_iarray;
}