darwin-c.c   [plain text]

/* Darwin support needed only by C/C++ frontends.
   Copyright (C) 2001, 2003, 2004  Free Software Foundation, Inc.
   Contributed by Apple Computer Inc.

This file is part of GCC.

GCC 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.

GCC 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 GCC; see the file COPYING.  If not, write to
the Free Software Foundation, 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA.  */

#include "config.h"
#include "system.h"
#include "coretypes.h"
#include "tm.h"
#include "cpplib.h"
#include "tree.h"
#include "c-pragma.h"
#include "c-tree.h"
#include "c-incpath.h"
#include "toplev.h"
#include "tm_p.h"

/* Pragmas.  */

#define BAD(msgid) do { warning (msgid); return; } while (0)
#define BAD2(msgid, arg) do { warning (msgid, arg); return; } while (0)

static bool using_frameworks = false;

/* APPLE LOCAL CALL_ON_LOAD/CALL_ON_UNLOAD pragmas  20020202 --turly  */
static void directive_with_named_function (const char *, void (*sec_f)(void));

/* Maintain a small stack of alignments.  This is similar to pragma
   pack's stack, but simpler.  */

/* APPLE LOCAL begin Macintosh alignment 2001-12-17 --ff */
static void push_field_alignment (int, int, int);
/* APPLE LOCAL end Macintosh alignment 2001-12-17 --ff */
static void pop_field_alignment (void);
static const char *find_subframework_file (const char *, const char *);
static void add_system_framework_path (char *);
static const char *find_subframework_header (cpp_reader *pfile, const char *header,
					     cpp_dir **dirp);

/* APPLE LOCAL begin Macintosh alignment 2002-1-22 --ff */
/* There are four alignment modes supported on the Apple Macintosh
   platform: power, mac68k, natural, and packed.  These modes are
   identified as follows:
     if maximum_field_alignment != 0
       mode = packed
     else if TARGET_ALIGN_NATURAL
       mode = natural
     else if TARGET_ALIGN_MAC68K
       mode
     else
       mode = power
   These modes are saved on the alignment stack by saving the values
   of maximum_field_alignment, TARGET_ALIGN_MAC68K, and 
   TARGET_ALIGN_NATURAL.  */
typedef struct align_stack
{
  int alignment;
  unsigned long mac68k;
  unsigned long natural;
  struct align_stack * prev;
} align_stack;
/* APPLE LOCAL end Macintosh alignment 2002-1-22 --ff */

static struct align_stack * field_align_stack = NULL;

/* APPLE LOCAL begin Macintosh alignment 2001-12-17 --ff */
static void
push_field_alignment (int bit_alignment, 
		      int mac68k_alignment, int natural_alignment)
{
  align_stack *entry = (align_stack *) xmalloc (sizeof (align_stack));

  entry->alignment = maximum_field_alignment;
  entry->mac68k = TARGET_ALIGN_MAC68K;
  entry->natural = TARGET_ALIGN_NATURAL;
  entry->prev = field_align_stack;
  field_align_stack = entry;

  maximum_field_alignment = bit_alignment;
  if (mac68k_alignment)
    rs6000_alignment_flags |= MASK_ALIGN_MAC68K;
  else
    rs6000_alignment_flags &= ~MASK_ALIGN_MAC68K;
  if (natural_alignment)
    rs6000_alignment_flags |= MASK_ALIGN_NATURAL;
  else
    rs6000_alignment_flags &= ~MASK_ALIGN_NATURAL;
}
/* APPLE LOCAL end Macintosh alignment 2001-12-17 --ff */

static void
pop_field_alignment (void)
{
  if (field_align_stack)
    {
      align_stack *entry = field_align_stack;

      maximum_field_alignment = entry->alignment;
/* APPLE LOCAL begin Macintosh alignment 2001-12-17 --ff */
      if (entry->mac68k)
	rs6000_alignment_flags |= MASK_ALIGN_MAC68K;
      else
	rs6000_alignment_flags &= ~MASK_ALIGN_MAC68K;
      if (entry->natural)
	rs6000_alignment_flags |= MASK_ALIGN_NATURAL;
      else
	rs6000_alignment_flags &= ~MASK_ALIGN_NATURAL;
/* APPLE LOCAL end Macintosh alignment 2001-12-17 --ff */
      field_align_stack = entry->prev;
      free (entry);
    }
  else
    error ("too many #pragma options align=reset");
}

/* Handlers for Darwin-specific pragmas.  */

void
darwin_pragma_ignore (cpp_reader *pfile ATTRIBUTE_UNUSED)
{
  /* Do nothing.  */
}

/* #pragma options align={mac68k|power|reset} */

void
darwin_pragma_options (cpp_reader *pfile ATTRIBUTE_UNUSED)
{
  const char *arg;
  tree t, x;

  if (c_lex (&t) != CPP_NAME)
    BAD ("malformed '#pragma options', ignoring");
  arg = IDENTIFIER_POINTER (t);
  if (strcmp (arg, "align"))
    BAD ("malformed '#pragma options', ignoring");
  if (c_lex (&t) != CPP_EQ)
    BAD ("malformed '#pragma options', ignoring");
  if (c_lex (&t) != CPP_NAME)
    BAD ("malformed '#pragma options', ignoring");

  if (c_lex (&x) != CPP_EOF)
    warning ("junk at end of '#pragma options'");

  arg = IDENTIFIER_POINTER (t);
/* APPLE LOCAL begin Macintosh alignment 2002-1-22 --ff */
  if (!strcmp (arg, "mac68k"))
    push_field_alignment (0, 1, 0);
  else if (!strcmp (arg, "native"))	/* equivalent to power on PowerPC */
    push_field_alignment (0, 0, 0);
  else if (!strcmp (arg, "natural"))
    push_field_alignment (0, 0, 1);
  else if (!strcmp (arg, "packed"))
    push_field_alignment (8, 0, 0);
  else if (!strcmp (arg, "power"))
    push_field_alignment (0, 0, 0);
  else if (!strcmp (arg, "reset"))
    pop_field_alignment ();
  else
    warning ("malformed '#pragma options align={mac68k|power|natural|reset}', ignoring");
/* APPLE LOCAL end Macintosh alignment 2002-1-22 --ff */
}

/* APPLE LOCAL begin Macintosh alignment 2002-1-22 --ff */
/* #pragma pack ()
   #pragma pack (N)  
   
   We have a problem handling the semantics of these directives since,
   to play well with the Macintosh alignment directives, we want the
   usual pack(N) form to do a push of the previous alignment state.
   Do we want pack() to do another push or a pop?  */

void
darwin_pragma_pack (cpp_reader *pfile ATTRIBUTE_UNUSED)
{
  tree x;
  int align = -1;
  enum cpp_ttype token;
  enum { set, push, pop } action;

  if (c_lex (&x) != CPP_OPEN_PAREN)
    BAD ("missing '(' after '#pragma pack' - ignored");
  token = c_lex (&x);
  if (token == CPP_CLOSE_PAREN)
    {
      action = pop;  		/* or "set" ???  */    
      align = 0;
    }
  else if (token == CPP_NUMBER)
    {
      align = TREE_INT_CST_LOW (x);
      action = push;
      if (c_lex (&x) != CPP_CLOSE_PAREN)
	BAD ("malformed '#pragma pack' - ignored");
    }
  else
    BAD ("malformed '#pragma pack' - ignored");

  if (c_lex (&x) != CPP_EOF)
    warning ("junk at end of '#pragma pack'");
    
  switch (align)
    {
    case 0:
    case 1:
    case 2:
    case 4:
    case 8:
    case 16:
      align *= BITS_PER_UNIT;
      break;
    default:
      BAD2 ("alignment must be a small power of two, not %d", align);
    }
  
  switch (action)
    {
    case pop:   pop_field_alignment ();		      break;
    case push:  push_field_alignment (align, 0, 0);   break;
    case set:   				      break;
    }
}
/* APPLE LOCAL end Macintosh alignment 2002-1-22 --ff */

/* #pragma unused ([var {, var}*]) */

void
darwin_pragma_unused (cpp_reader *pfile ATTRIBUTE_UNUSED)
{
  tree decl, x;
  int tok;

  if (c_lex (&x) != CPP_OPEN_PAREN)
    BAD ("missing '(' after '#pragma unused', ignoring");

  while (1)
    {
      tok = c_lex (&decl);
      if (tok == CPP_NAME && decl)
	{
	  tree local = lookup_name (decl);
	  if (local && (TREE_CODE (local) == PARM_DECL
			|| TREE_CODE (local) == VAR_DECL))
	    TREE_USED (local) = 1;
	  tok = c_lex (&x);
	  if (tok != CPP_COMMA)
	    break;
	}
    }

  if (tok != CPP_CLOSE_PAREN)
    BAD ("missing ')' after '#pragma unused', ignoring");

  if (c_lex (&x) != CPP_EOF)
    warning ("junk at end of '#pragma unused'");
}

static struct {
  size_t len;
  const char *name;
  cpp_dir* dir;
} *frameworks_in_use;
static int num_frameworks = 0;
static int max_frameworks = 0;


/* Remember which frameworks have been seen, so that we can ensure
   that all uses of that framework come from the same framework.  DIR
   is the place where the named framework NAME, which is of length
   LEN, was found.  We copy the directory name from NAME, as it will be
   freed by others.  */

static void
add_framework (const char *name, size_t len, cpp_dir *dir)
{
  char *dir_name;
  int i;
  for (i = 0; i < num_frameworks; ++i)
    {
      if (len == frameworks_in_use[i].len
	  && strncmp (name, frameworks_in_use[i].name, len) == 0)
	{
	  return;
	}
    }
  if (i >= max_frameworks)
    {
      max_frameworks = i*2;
      max_frameworks += i == 0;
      frameworks_in_use = xrealloc (frameworks_in_use,
				    max_frameworks*sizeof(*frameworks_in_use));
    }
  dir_name = xmalloc (len + 1);
  memcpy (dir_name, name, len);
  dir_name[len] = '\0';
  frameworks_in_use[num_frameworks].name = dir_name;
  frameworks_in_use[num_frameworks].len = len;
  frameworks_in_use[num_frameworks].dir = dir;
  ++num_frameworks;
}

/* Recall if we have seen the named framework NAME, before, and where
   we saw it.  NAME is LEN bytes long.  The return value is the place
   where it was seen before.  */

static struct cpp_dir*
find_framework (const char *name, size_t len)
{
  int i;
  for (i = 0; i < num_frameworks; ++i)
    {
      if (len == frameworks_in_use[i].len
	  && strncmp (name, frameworks_in_use[i].name, len) == 0)
	{
	  return frameworks_in_use[i].dir;
	}
    }
  return 0;
}

/* There are two directories in a framework that contain header files,
   Headers and PrivateHeaders.  We search Headers first as it is more
   common to upgrade a header from PrivateHeaders to Headers and when
   that is done, the old one might hang around and be out of data,
   causing grief.  */

struct framework_header {const char * dirName; int dirNameLen; };
static struct framework_header framework_header_dirs[] = {
  { "Headers", 7 },
  { "PrivateHeaders", 14 },
  { NULL, 0 }
};

/* Returns a pointer to a malloced string that contains the real pathname
   to the file, given the base name and the name.  */

static char *
framework_construct_pathname (const char *fname, cpp_dir *dir)
{
  char *buf;
  size_t fname_len, frname_len;
  cpp_dir *fast_dir;
  char *frname;
  struct stat st;
  int i;

  /* Framework names must have a / in them.  */
  buf = strchr (fname, '/');
  if (buf)
    fname_len = buf - fname;
  else
    return 0;

  fast_dir = find_framework (fname, fname_len);

  /* Framework includes must all come from one framework.  */
  if (fast_dir && dir != fast_dir)
    return 0;

  frname = xmalloc (strlen (fname) + dir->len + 2
		    + strlen(".framework/") + strlen("PrivateHeaders"));
  strncpy (&frname[0], dir->name, dir->len);
  frname_len = dir->len;
  if (frname_len && frname[frname_len-1] != '/')
    frname[frname_len++] = '/';
  strncpy (&frname[frname_len], fname, fname_len);
  frname_len += fname_len;
  strncpy (&frname[frname_len], ".framework/", strlen (".framework/"));
  frname_len += strlen (".framework/");

  /* Append framework_header_dirs and header file name */
  for (i = 0; framework_header_dirs[i].dirName; i++)
    {
      strncpy (&frname[frname_len], 
	       framework_header_dirs[i].dirName,
	       framework_header_dirs[i].dirNameLen);
      strcpy (&frname[frname_len + framework_header_dirs[i].dirNameLen],
	      &fname[fname_len]);

      if (stat (frname, &st) == 0)
	{
	  if (fast_dir == 0)
	    add_framework (fname, fname_len, dir);
	  return frname;
	}
    }

  free (frname);
  return 0;
}

/* Search for FNAME in sub-frameworks.  pname is the context that we
   wish to search in.  Return the path the file was found at,
   otherwise return 0.  */

static const char*
find_subframework_file (const char *fname, const char *pname)
{
  char *sfrname;
  const char *dot_framework = ".framework/";
  char *bufptr; 
  int sfrname_len, i, fname_len; 
  struct cpp_dir *fast_dir;
  static struct cpp_dir subframe_dir;
  struct stat st;

  bufptr = strchr (fname, '/');

  /* Subframework files must have / in the name.  */
  if (bufptr == 0)
    return 0;
    
  fname_len = bufptr - fname;
  fast_dir = find_framework (fname, fname_len);

  /* Sub framework header filename includes parent framework name and
     header name in the "CarbonCore/OSUtils.h" form. If it does not
     include slash it is not a sub framework include.  */
  bufptr = strstr (pname, dot_framework);

  /* If the parent header is not of any framework, then this header
     can not be part of any subframework.  */
  if (!bufptr)
    return 0;

  /* Now translate. For example,                  +- bufptr
     fname = CarbonCore/OSUtils.h                 | 
     pname = /System/Library/Frameworks/Foundation.framework/Headers/Foundation.h
     into
     sfrname = /System/Library/Frameworks/Foundation.framework/Frameworks/CarbonCore.framework/Headers/OSUtils.h */

  sfrname = (char *) xmalloc (strlen (pname) + strlen (fname) + 2 +
			      strlen ("Frameworks/") + strlen (".framework/")
			      + strlen ("PrivateHeaders"));
 
  bufptr += strlen (dot_framework);

  sfrname_len = bufptr - pname; 

  strncpy (&sfrname[0], pname, sfrname_len);

  strncpy (&sfrname[sfrname_len], "Frameworks/", strlen ("Frameworks/"));
  sfrname_len += strlen("Frameworks/");

  strncpy (&sfrname[sfrname_len], fname, fname_len);
  sfrname_len += fname_len;

  strncpy (&sfrname[sfrname_len], ".framework/", strlen (".framework/"));
  sfrname_len += strlen (".framework/");

  /* Append framework_header_dirs and header file name */
  for (i = 0; framework_header_dirs[i].dirName; i++)
    {
      strncpy (&sfrname[sfrname_len], 
	       framework_header_dirs[i].dirName,
	       framework_header_dirs[i].dirNameLen);
      strcpy (&sfrname[sfrname_len + framework_header_dirs[i].dirNameLen],
	      &fname[fname_len]);
    
      if (stat (sfrname, &st) == 0)
	{
	  if (fast_dir != &subframe_dir)
	    {
	      if (fast_dir)
		warning ("subframework include %s conflicts with framework include",
			 fname);
	      else
		add_framework (fname, fname_len, &subframe_dir);
	    }

	  return sfrname;
	}
    }
  free (sfrname);

  return 0;
}

/* Add PATH to the system includes. PATH must be malloc-ed and
   NUL-terminated.  System framework paths are C++ aware.  */

static void
add_system_framework_path (char *path)
{
  int cxx_aware = 1;
  cpp_dir *p;

  p = xmalloc (sizeof (cpp_dir));
  p->next = NULL;
  p->name = path;
  p->sysp = 1 + !cxx_aware;
  p->construct = framework_construct_pathname;
  using_frameworks = 1;

  add_cpp_dir_path (p, SYSTEM);
}

/* Add PATH to the bracket includes. PATH must be malloc-ed and
   NUL-terminated.  */

void
add_framework_path (char *path)
{
  cpp_dir *p;

  p = xmalloc (sizeof (cpp_dir));
  p->next = NULL;
  p->name = path;
  p->sysp = 0;
  p->construct = framework_construct_pathname;
  using_frameworks = 1;

  add_cpp_dir_path (p, BRACKET);
}

static const char *framework_defaults [] = 
  {
    "/System/Library/Frameworks",
    "/Library/Frameworks",
    "/Local/Library/Frameworks",
  };


/* Register all the system framework paths if STDINC is true and setup
   the missing_header callback for subframework searching if any
   frameworks had been registered.  */

void
darwin_register_frameworks (int stdinc)
{
  if (stdinc)
    {
      size_t i;

      /* Setup default search path for frameworks.  */
      for (i=0; i<sizeof (framework_defaults)/sizeof(const char *); ++i)
	{
	  /* System Framework headers are cxx aware.  */
	  add_system_framework_path (xstrdup (framework_defaults[i]));
	}
    }

  if (using_frameworks)
    cpp_get_callbacks (parse_in)->missing_header = find_subframework_header;
}

/* Search for HEADER in context dependent way.  The return value is
   the malloced name of a header to try and open, if any, or NULL
   otherwise.  This is called after normal header lookup processing
   fails to find a header.  We search each file in the include stack,
   using FUNC, starting from the most deeply nested include and
   finishing with the main input file.  We stop searching when FUNC
   returns non-zero.  */

static const char*
find_subframework_header (cpp_reader *pfile, const char *header, cpp_dir **dirp)
{
  const char *fname = header;
  struct cpp_buffer *b;
  const char *n;

  for (b = cpp_get_buffer (pfile);
       b && cpp_get_file (b) && cpp_get_path (cpp_get_file (b));
       b = cpp_get_prev (b))
    {
      n = find_subframework_file (fname, cpp_get_path (cpp_get_file (b)));
      if (n)
	{
	  /* Logically, the place where we found the subframework is
	     the place where we found the Framework that contains the
	     subframework.  This is useful for tracking wether or not
	     we are in a system header.  */
	  *dirp = cpp_get_dir (cpp_get_file (b));
	  return n;
	}
    }

  return 0;
}

struct target_c_incpath_s target_c_incpath = C_INCPATH_INIT;

/* APPLE LOCAL begin CALL_ON_LOAD/CALL_ON_UNLOAD pragmas  20020202 --turly  */
extern void mod_init_section (void), mod_term_section (void);
/* Grab the function name from the pragma line and output it to the
   assembly output file with the parameter DIRECTIVE.  Called by the
   pragma CALL_ON_LOAD and CALL_ON_UNLOAD handlers below.
   So: "#pragma CALL_ON_LOAD foo"  will output ".mod_init_func _foo".  */

static void directive_with_named_function (const char *pragma_name,
			         void (*section_function) (void))
{
  tree decl;
  int tok;

  tok = c_lex (&decl);
  if (tok == CPP_NAME && decl)
    {
      extern FILE *asm_out_file;

      section_function ();
      fprintf (asm_out_file, "\t.long _%s\n", IDENTIFIER_POINTER (decl));

      if (c_lex (&decl) != CPP_EOF)
	warning ("junk at end of #pragma %s <function_name>\n", pragma_name);
    }
  else
    warning ("function name expected after #pragma %s\n", pragma_name);
}
void
darwin_pragma_call_on_load (cpp_reader *pfile ATTRIBUTE_UNUSED)
{
  directive_with_named_function ("CALL_ON_LOAD", mod_init_section);
}
void
darwin_pragma_call_on_unload (cpp_reader *pfile ATTRIBUTE_UNUSED)
{
  directive_with_named_function ("CALL_ON_UNLOAD", mod_term_section);
}
/* APPLE LOCAL end CALL_ON_LOAD/CALL_ON_UNLOAD pragmas  20020202 --turly  */

/* APPLE LOCAL begin CALL_ON_MODULE_BIND deprecated 2002-4-10 --ff */
void
darwin_pragma_call_on_module_bind (cpp_reader *pfile ATTRIBUTE_UNUSED)
{
  warning ("#pragma CALL_ON_MODULE_BIND is no longer supported, ignoring.  "
  	   "Use CALL_ON_LOAD instead.");
}
/* APPLE LOCAL end CALL_ON_MODULE_BIND deprecated 2002-4-10 --ff */

/* APPLE LOCAL begin temporary pragmas 2001-07-05 --sts */
/* These need to live only long enough to get their uses flushed out
   of the system.  */
void
darwin_pragma_cc_no_mach_text_sections (cpp_reader *pfile ATTRIBUTE_UNUSED)
{
  warning ("#pragma CC_NO_MACH_TEXT_SECTIONS is no longer supported, ignoring");
}

void
darwin_pragma_cc_opt_off (cpp_reader *pfile ATTRIBUTE_UNUSED)
{
  warning ("#pragma CC_OPT_OFF is no longer supported, ignoring");
}

void
darwin_pragma_cc_opt_on (cpp_reader *pfile ATTRIBUTE_UNUSED)
{
  warning ("#pragma CC_OPT_ON is no longer supported, ignoring");
}

void
darwin_pragma_cc_opt_restore (cpp_reader *pfile ATTRIBUTE_UNUSED)
{
  warning ("#pragma CC_OPT_RESTORE is no longer supported, ignoring");
}

void
darwin_pragma_cc_writable_strings (cpp_reader *pfile ATTRIBUTE_UNUSED)
{
  warning ("#pragma CC_WRITABLE_STRINGS is no longer supported, ignoring");
}

void
darwin_pragma_cc_non_writable_strings (cpp_reader *pfile ATTRIBUTE_UNUSED)
{
  warning ("#pragma CC_NON_WRITABLE_STRINGS is no longer supported, ignoring");
}
/* APPLE LOCAL end temporary pragmas 2001-07-05 --sts */