gcc.c

GCC编译器源代码

  for (temp = failure_delete_queue; temp; temp = temp->next)
    delete_if_ordinary (temp->name);
}

static void
clear_failure_queue ()
{
  failure_delete_queue = 0;
}

/* Routine to add variables to the environment.  We do this to pass
   the pathname of the gcc driver, and the directories search to the
   collect2 program, which is being run as ld.  This way, we can be
   sure of executing the right compiler when collect2 wants to build
   constructors and destructors.  Since the environment variables we
   use come from an obstack, we don't have to worry about allocating
   space for them.  */

#ifndef HAVE_PUTENV

void
putenv (str)
     char *str;
{
#ifndef VMS			/* nor about VMS */

  extern char **environ;
  char **old_environ = environ;
  char **envp;
  int num_envs = 0;
  int name_len = 1;
  int str_len = strlen (str);
  char *p = str;
  int ch;

  while ((ch = *p++) != '\0' && ch != '=')
    name_len++;

  if (!ch)
    abort ();

  /* Search for replacing an existing environment variable, and
     count the number of total environment variables.  */
  for (envp = old_environ; *envp; envp++)
    {
      num_envs++;
      if (!strncmp (str, *envp, name_len))
	{
	  *envp = str;
	  return;
	}
    }

  /* Add a new environment variable */
  environ = (char **) xmalloc (sizeof (char *) * (num_envs+2));
  *environ = str;
  bcopy ((char *) old_environ, (char *) (environ + 1),
	 sizeof (char *) * (num_envs+1));

#endif	/* VMS */
}

#endif	/* HAVE_PUTENV */


/* Build a list of search directories from PATHS.
   PREFIX is a string to prepend to the list.
   If CHECK_DIR_P is non-zero we ensure the directory exists.
   This is used mostly by putenv_from_prefixes so we use `collect_obstack'.
   It is also used by the --print-search-dirs flag.  */

static char *
build_search_list (paths, prefix, check_dir_p)
     struct path_prefix *paths;
     char *prefix;
     int check_dir_p;
{
  int suffix_len = (machine_suffix) ? strlen (machine_suffix) : 0;
  int just_suffix_len
    = (just_machine_suffix) ? strlen (just_machine_suffix) : 0;
  int first_time = TRUE;
  struct prefix_list *pprefix;

  obstack_grow (&collect_obstack, prefix, strlen (prefix));

  for (pprefix = paths->plist; pprefix != 0; pprefix = pprefix->next)
    {
      int len = strlen (pprefix->prefix);

      if (machine_suffix
	  && (! check_dir_p
	      || is_directory (pprefix->prefix, machine_suffix, 0)))
	{
	  if (!first_time)
	    obstack_1grow (&collect_obstack, PATH_SEPARATOR);
	    
	  first_time = FALSE;
	  obstack_grow (&collect_obstack, pprefix->prefix, len);
	  obstack_grow (&collect_obstack, machine_suffix, suffix_len);
	}

      if (just_machine_suffix
	  && pprefix->require_machine_suffix == 2
	  && (! check_dir_p
	      || is_directory (pprefix->prefix, just_machine_suffix, 0)))
	{
	  if (! first_time)
	    obstack_1grow (&collect_obstack, PATH_SEPARATOR);
	    
	  first_time = FALSE;
	  obstack_grow (&collect_obstack, pprefix->prefix, len);
	  obstack_grow (&collect_obstack, just_machine_suffix,
			just_suffix_len);
	}

      if (! pprefix->require_machine_suffix)
	{
	  if (! first_time)
	    obstack_1grow (&collect_obstack, PATH_SEPARATOR);

	  first_time = FALSE;
	  obstack_grow (&collect_obstack, pprefix->prefix, len);
	}
    }

  obstack_1grow (&collect_obstack, '\0');
  return obstack_finish (&collect_obstack);
}

/* Rebuild the COMPILER_PATH and LIBRARY_PATH environment variables
   for collect.  */

static void
putenv_from_prefixes (paths, env_var)
     struct path_prefix *paths;
     char *env_var;
{
  putenv (build_search_list (paths, env_var, 1));
}

/* Search for NAME using the prefix list PREFIXES.  MODE is passed to
   access to check permissions.
   Return 0 if not found, otherwise return its name, allocated with malloc.  */

static char *
find_a_file (pprefix, name, mode)
     struct path_prefix *pprefix;
     char *name;
     int mode;
{
  char *temp;
  char *file_suffix = ((mode & X_OK) != 0 ? EXECUTABLE_SUFFIX : "");
  struct prefix_list *pl;
  int len = pprefix->max_len + strlen (name) + strlen (file_suffix) + 1;

  if (machine_suffix)
    len += strlen (machine_suffix);

  temp = xmalloc (len);

  /* Determine the filename to execute (special case for absolute paths).  */

  if (*name == '/' || *name == DIR_SEPARATOR
      /* Check for disk name on MS-DOS-based systems.  */
      || (DIR_SEPARATOR == '\\' && name[1] == ':'
	  && (name[2] == DIR_SEPARATOR || name[2] == '/')))
    {
      if (access (name, mode))
	{
	  strcpy (temp, name);
	  return temp;
	}
    }
  else
    for (pl = pprefix->plist; pl; pl = pl->next)
      {
	if (machine_suffix)
	  {
	    /* Some systems have a suffix for executable files.
	       So try appending that first.  */
	    if (file_suffix[0] != 0)
	      {
		strcpy (temp, pl->prefix);
		strcat (temp, machine_suffix);
		strcat (temp, name);
		strcat (temp, file_suffix);
		if (access (temp, mode) == 0)
		  {
		    if (pl->used_flag_ptr != 0)
		      *pl->used_flag_ptr = 1;
		    return temp;
		  }
	      }

	    /* Now try just the name.  */
	    strcpy (temp, pl->prefix);
	    strcat (temp, machine_suffix);
	    strcat (temp, name);
	    if (access (temp, mode) == 0)
	      {
		if (pl->used_flag_ptr != 0)
		  *pl->used_flag_ptr = 1;
		return temp;
	      }
	  }

	/* Certain prefixes are tried with just the machine type,
	   not the version.  This is used for finding as, ld, etc.  */
	if (just_machine_suffix && pl->require_machine_suffix == 2)
	  {
	    /* Some systems have a suffix for executable files.
	       So try appending that first.  */
	    if (file_suffix[0] != 0)
	      {
		strcpy (temp, pl->prefix);
		strcat (temp, just_machine_suffix);
		strcat (temp, name);
		strcat (temp, file_suffix);
		if (access (temp, mode) == 0)
		  {
		    if (pl->used_flag_ptr != 0)
		      *pl->used_flag_ptr = 1;
		    return temp;
		  }
	      }

	    strcpy (temp, pl->prefix);
	    strcat (temp, just_machine_suffix);
	    strcat (temp, name);
	    if (access (temp, mode) == 0)
	      {
		if (pl->used_flag_ptr != 0)
		  *pl->used_flag_ptr = 1;
		return temp;
	      }
	  }

	/* Certain prefixes can't be used without the machine suffix
	   when the machine or version is explicitly specified.  */
	if (! pl->require_machine_suffix)
	  {
	    /* Some systems have a suffix for executable files.
	       So try appending that first.  */
	    if (file_suffix[0] != 0)
	      {
		strcpy (temp, pl->prefix);
		strcat (temp, name);
		strcat (temp, file_suffix);
		if (access (temp, mode) == 0)
		  {
		    if (pl->used_flag_ptr != 0)
		      *pl->used_flag_ptr = 1;
		    return temp;
		  }
	      }

	    strcpy (temp, pl->prefix);
	    strcat (temp, name);
	    if (access (temp, mode) == 0)
	      {
		if (pl->used_flag_ptr != 0)
		  *pl->used_flag_ptr = 1;
		return temp;
	      }
	  }
      }

  free (temp);
  return 0;
}

/* Add an entry for PREFIX in PLIST.  If FIRST is set, it goes
   at the start of the list, otherwise it goes at the end.

   If WARN is nonzero, we will warn if no file is found
   through this prefix.  WARN should point to an int
   which will be set to 1 if this entry is used.

   COMPONENT is the value to be passed to update_path.

   REQUIRE_MACHINE_SUFFIX is 1 if this prefix can't be used without
   the complete value of machine_suffix.
   2 means try both machine_suffix and just_machine_suffix.  */

static void
add_prefix (pprefix, prefix, component, first, require_machine_suffix, warn)
     struct path_prefix *pprefix;
     char *prefix;
     char *component;
     int first;
     int require_machine_suffix;
     int *warn;
{
  struct prefix_list *pl, **prev;
  int len;

  if (! first && pprefix->plist)
    {
      for (pl = pprefix->plist; pl->next; pl = pl->next)
	;
      prev = &pl->next;
    }
  else
    prev = &pprefix->plist;

  /* Keep track of the longest prefix */

  prefix = update_path (prefix, component);
  len = strlen (prefix);
  if (len > pprefix->max_len)
    pprefix->max_len = len;

  pl = (struct prefix_list *) xmalloc (sizeof (struct prefix_list));
  pl->prefix = save_string (prefix, len);
  pl->require_machine_suffix = require_machine_suffix;
  pl->used_flag_ptr = warn;
  if (warn)
    *warn = 0;

  if (*prev)
    pl->next = *prev;
  else
    pl->next = (struct prefix_list *) 0;
  *prev = pl;
}

/* Print warnings for any prefixes in the list PPREFIX that were not used.  */

static void
unused_prefix_warnings (pprefix)
     struct path_prefix *pprefix;
{
  struct prefix_list *pl = pprefix->plist;

  while (pl)
    {
      if (pl->used_flag_ptr != 0 && !*pl->used_flag_ptr)
	{
	  if (pl->require_machine_suffix && machine_suffix)
	    error ("file path prefix `%s%s' never used", pl->prefix,
		   machine_suffix);
	  else
	    error ("file path prefix `%s' never used", pl->prefix);

	  /* Prevent duplicate warnings.  */
	  *pl->used_flag_ptr = 1;
	}

      pl = pl->next;
    }
}

/* Get rid of all prefixes built up so far in *PLISTP.  */

static void
free_path_prefix (pprefix)
     struct path_prefix *pprefix;
{
  struct prefix_list *pl = pprefix->plist;
  struct prefix_list *temp;

  while (pl)
    {
      temp = pl;
      pl = pl->next;
      free (temp->prefix);
      free ((char *) temp);
    }

  pprefix->plist = (struct prefix_list *) 0;
}

/* Execute the command specified by the arguments on the current line of spec.
   When using pipes, this includes several piped-together commands
   with `|' between them.

   Return 0 if successful, -1 if failed.  */

static int
execute ()
{
  int i;
  int n_commands;		/* # of command.  */
  char *string;
  struct command
    {
      char *prog;		/* program name.  */
      char **argv;		/* vector of args.  */
      int pid;			/* pid of process for this command.  */
    };

  struct command *commands;	/* each command buffer with above info.  */

  /* Count # of piped commands.  */
  for (n_commands = 1, i = 0; i < argbuf_index; i++)
    if (strcmp (argbuf[i], "|") == 0)
      n_commands++;

  /* Get storage for each command.  */
  commands
    = (struct command *) alloca (n_commands * sizeof (struct command));

  /* Split argbuf into its separate piped processes,
     and record info about each one.
     Also search for the programs that are to be run.  */

  commands[0].prog = argbuf[0]; /* first command.  */
  commands[0].argv = &argbuf[0];
  string = find_a_file (&exec_prefixes, commands[0].prog, X_OK);
  if (string)
    commands[0].argv[0] = string;

  for (n_commands = 1, i = 0; i < argbuf_index; i++)
    if (strcmp (argbuf[i], "|") == 0)
      {				/* each command.  */
#if defined (__MSDOS__) || (defined (_WIN32) && ! defined (__CYGWIN32__)) || defined (OS2) || defined (VMS)
        fatal ("-pipe not supported");
#endif
	argbuf[i] = 0;	/* termination of command args.  */
	commands[n_commands].prog = argbuf[i + 1];
	commands[n_commands].argv = &argbuf[i + 1];
	string = find_a_file (&exec_prefixes, commands[n_commands].prog, X_OK);
	if (string)
	  commands[n_commands].argv[0] = string;
	n_commands++;
      }

  argbuf[argbuf_index] = 0;

  /* If -v, print what we are about to do, and maybe query.  */

  if (verbose_flag)
    {
      /* Print each piped command as a separate line.  */
      for (i = 0; i < n_comma