cpplib.c

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/* CPP Library.
   Copyright (C) 1986, 87, 89, 92-6, 1997 Free Software Foundation, Inc.
   Contributed by Per Bothner, 1994-95.
   Based on CCCP program by Paul Rubin, June 1986
   Adapted to ANSI C, Richard Stallman, Jan 1987

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, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */

#include "config.h"

#ifndef STDC_VALUE
#define STDC_VALUE 1
#endif

#include <ctype.h>
#include <stdio.h>
#include <signal.h>

#ifdef HAVE_STDLIB_H
#include <stdlib.h>
#endif

#ifdef TIME_WITH_SYS_TIME
# include <sys/time.h>
# include <time.h>
#else
# if HAVE_SYS_TIME_H
# include <sys/time.h>
# else
#  include <time.h>
#endif
#endif

#ifdef HAVE_SYS_TIMES_H
#include <sys/times.h>
#endif

#ifdef HAVE_SYS_RESOURCE_H
# include <sys/resource.h>
#endif

#ifdef HAVE_FCNTL_H
# include <fcntl.h>
#endif

#if HAVE_LIMITS_H
# include <limits.h>
#endif

#ifdef HAVE_STDLIB_H
# include <stdlib.h>
#endif

#ifdef HAVE_STRING_H
# include <string.h>
# else
# ifdef HAVE_STRINGS_H
#  include <strings.h>
#endif
#endif

/* This defines "errno" properly for VMS, and gives us EACCES.  */
#include <errno.h>

#include "cpplib.h"
#include "cpphash.h"
#include "gansidecl.h"

#ifdef NEED_DECLARATION_INDEX
extern char *index ();
#endif

#ifdef NEED_DECLARATION_RINDEX
extern char *rindex ();
#endif

#ifdef NEED_DECLARATION_GETENV
extern char *getenv ();
#endif

extern char *update_path ();

#ifndef O_RDONLY
#define O_RDONLY 0
#endif

#undef MIN
#undef MAX
#define MIN(X,Y) ((X) < (Y) ? (X) : (Y))
#define MAX(X,Y) ((X) > (Y) ? (X) : (Y))

/* Find the largest host integer type and set its size and type.
   Watch out: on some crazy hosts `long' is shorter than `int'.  */

#ifndef HOST_WIDE_INT
# if HAVE_INTTYPES_H
#  include <inttypes.h>
#  define HOST_WIDE_INT intmax_t
# else
#  if (HOST_BITS_PER_LONG <= HOST_BITS_PER_INT \
       && HOST_BITS_PER_LONGLONG <= HOST_BITS_PER_INT)
#   define HOST_WIDE_INT int
#  else
#  if (HOST_BITS_PER_LONGLONG <= HOST_BITS_PER_LONG \
       || ! (defined LONG_LONG_MAX || defined LLONG_MAX))
#   define HOST_WIDE_INT long
#  else
#   define HOST_WIDE_INT long long
#  endif
#  endif
# endif
#endif

#ifndef S_ISREG
#define S_ISREG(m) (((m) & S_IFMT) == S_IFREG)
#endif

#ifndef S_ISDIR
#define S_ISDIR(m) (((m) & S_IFMT) == S_IFDIR)
#endif

/* By default, colon separates directories in a path.  */
#ifndef PATH_SEPARATOR
#define PATH_SEPARATOR ':'
#endif

#ifndef STANDARD_INCLUDE_DIR
#define STANDARD_INCLUDE_DIR "/usr/include"
#endif
#ifndef INCLUDE_LEN_FUDGE
#define INCLUDE_LEN_FUDGE 0
#endif

/* Symbols to predefine.  */

#ifdef CPP_PREDEFINES
static char *predefs = CPP_PREDEFINES;
#else
static char *predefs = "";
#endif

/* We let tm.h override the types used here, to handle trivial differences
   such as the choice of unsigned int or long unsigned int for size_t.
   When machines start needing nontrivial differences in the size type,
   it would be best to do something here to figure out automatically
   from other information what type to use.  */

/* The string value for __SIZE_TYPE__.  */

#ifndef SIZE_TYPE
#define SIZE_TYPE "long unsigned int"
#endif

/* The string value for __PTRDIFF_TYPE__.  */

#ifndef PTRDIFF_TYPE
#define PTRDIFF_TYPE "long int"
#endif

/* The string value for __WCHAR_TYPE__.  */

#ifndef WCHAR_TYPE
#define WCHAR_TYPE "int"
#endif
#define CPP_WCHAR_TYPE(PFILE) \
	(CPP_OPTIONS (PFILE)->cplusplus ? "__wchar_t" : WCHAR_TYPE)

/* The string value for __USER_LABEL_PREFIX__ */

#ifndef USER_LABEL_PREFIX
#define USER_LABEL_PREFIX ""
#endif

/* The string value for __REGISTER_PREFIX__ */

#ifndef REGISTER_PREFIX
#define REGISTER_PREFIX ""
#endif

/* In the definition of a #assert name, this structure forms
   a list of the individual values asserted.
   Each value is itself a list of "tokens".
   These are strings that are compared by name.  */

struct tokenlist_list {
  struct tokenlist_list *next;
  struct arglist *tokens;
};

struct assertion_hashnode {
  struct assertion_hashnode *next;	/* double links for easy deletion */
  struct assertion_hashnode *prev;
  /* also, a back pointer to this node's hash
     chain is kept, in case the node is the head
     of the chain and gets deleted.  */
  struct assertion_hashnode **bucket_hdr;
  int length;			/* length of token, for quick comparison */
  U_CHAR *name;			/* the actual name */
  /* List of token-sequences.  */
  struct tokenlist_list *value;
};

#define SKIP_WHITE_SPACE(p) do { while (is_hor_space[*p]) p++; } while (0)
#define SKIP_ALL_WHITE_SPACE(p) do { while (is_space[*p]) p++; } while (0)

#define PEEKN(N) (CPP_BUFFER (pfile)->rlimit - CPP_BUFFER (pfile)->cur >= (N) ? CPP_BUFFER (pfile)->cur[N] : EOF)
#define FORWARD(N) CPP_FORWARD (CPP_BUFFER (pfile), (N))
#define GETC() CPP_BUF_GET (CPP_BUFFER (pfile))
#define PEEKC() CPP_BUF_PEEK (CPP_BUFFER (pfile))
/* CPP_IS_MACRO_BUFFER is true if the buffer contains macro expansion.
   (Note that it is false while we're expanding marco *arguments*.) */
#define CPP_IS_MACRO_BUFFER(PBUF) ((PBUF)->cleanup == macro_cleanup)

/* Move all backslash-newline pairs out of embarrassing places.
   Exchange all such pairs following BP
   with any potentially-embarrassing characters that follow them.
   Potentially-embarrassing characters are / and *
   (because a backslash-newline inside a comment delimiter
   would cause it not to be recognized).  */

#define NEWLINE_FIX \
  do {while (PEEKC() == '\\' && PEEKN(1) == '\n') FORWARD(2); } while(0)

/* Same, but assume we've already read the potential '\\' into C.  */
#define NEWLINE_FIX1(C) do { \
    while ((C) == '\\' && PEEKC() == '\n') { FORWARD(1); (C) = GETC(); }\
  } while(0)

struct cpp_pending {
  struct cpp_pending *next;
  char *cmd;
  char *arg;
};

/* Forward declarations.  */

char *xmalloc ();
void cpp_fatal ();
void cpp_file_line_for_message PARAMS ((cpp_reader *, char *, int, int));
void cpp_hash_cleanup PARAMS ((cpp_reader *));
void cpp_message ();
void cpp_print_containing_files PARAMS ((cpp_reader *));

static void add_import ();
static void append_include_chain ();
static void make_assertion ();
static void path_include ();
static void initialize_builtins ();
static void initialize_char_syntax ();
extern void delete_macro ();
#if 0
static void trigraph_pcp ();
#endif
static int finclude ();
static void validate_else ();
static int comp_def_part ();
#ifdef abort
extern void fancy_abort ();
#endif
static int lookup_import ();
static int redundant_include_p ();
static is_system_include ();
static struct file_name_map *read_name_map ();
static char *read_filename_string ();
static int open_include_file ();
static int check_macro_name ();
static int compare_defs ();
static int compare_token_lists ();
static HOST_WIDE_INT eval_if_expression ();
static int change_newlines ();
extern int hashf ();
static struct arglist *read_token_list ();
static void free_token_list ();
static int safe_read ();
static void push_macro_expansion PARAMS ((cpp_reader *,
					  U_CHAR *, int, HASHNODE *));
static struct cpp_pending *nreverse_pending PARAMS ((struct cpp_pending *));
extern char *xrealloc ();
static char *xcalloc ();
static char *savestring ();

static void conditional_skip ();
static void skip_if_group ();

/* Last arg to output_line_command.  */
enum file_change_code {same_file, enter_file, leave_file};

/* External declarations.  */

extern HOST_WIDE_INT cpp_parse_expr PARAMS ((cpp_reader *));

extern FILE *fdopen ();
extern char *version_string;
extern struct tm *localtime ();

/* These functions are declared to return int instead of void since they
   are going to be placed in a table and some old compilers have trouble with
   pointers to functions returning void.  */

static int do_define ();
static int do_line ();
static int do_include ();
static int do_undef ();
static int do_error ();
static int do_pragma ();
static int do_ident ();
static int do_if ();
static int do_xifdef ();
static int do_else ();
static int do_elif ();
static int do_endif ();
static int do_sccs ();
static int do_once ();
static int do_assert ();
static int do_unassert ();
static int do_warning ();

struct file_name_list
  {
    struct file_name_list *next;
    char *fname;
    /* If the following is nonzero, it is a macro name.
       Don't include the file again if that macro is defined.  */
    U_CHAR *control_macro;
    /* If the following is nonzero, it is a C-language system include
       directory.  */
    int c_system_include_path;
    /* Mapping of file names for this directory.  */
    struct file_name_map *name_map;
    /* Non-zero if name_map is valid.  */
    int got_name_map;
  };

/* If a buffer's dir field is SELF_DIR_DUMMY, it means the file was found
   via the same directory as the file that #included it.  */
#define SELF_DIR_DUMMY ((struct file_name_list *) (~0))

/* #include "file" looks in source file dir, then stack.  */
/* #include <file> just looks in the stack.  */
/* -I directories are added to the end, then the defaults are added.  */
/* The */
static struct default_include {
  char *fname;			/* The name of the directory.  */
  char *component;		/* The component containing the directory */
  int cplusplus;		/* Only look here if we're compiling C++.  */
  int cxx_aware;		/* Includes in this directory don't need to
				   be wrapped in extern "C" when compiling
				   C++.  */
} include_defaults_array[]
#ifdef INCLUDE_DEFAULTS
  = INCLUDE_DEFAULTS;
#else
  = {
    /* Pick up GNU C++ specific include files.  */
    { GPLUSPLUS_INCLUDE_DIR, "G++", 1, 1 },
    { OLD_GPLUSPLUS_INCLUDE_DIR, 0, 1, 1 },
#ifdef CROSS_COMPILE
    /* This is the dir for fixincludes.  Put it just before
       the files that we fix.  */
    { GCC_INCLUDE_DIR, "GCC", 0, 0 },
    /* For cross-compilation, this dir name is generated
       automatically in Makefile.in.  */
    { CROSS_INCLUDE_DIR, "GCC",0, 0 },
#ifdef TOOL_INCLUDE_DIR
    /* This is another place that the target system's headers might be.  */
    { TOOL_INCLUDE_DIR, "BINUTILS", 0, 1 },
#endif
#else /* not CROSS_COMPILE */
#ifdef LOCAL_INCLUDE_DIR
    /* This should be /usr/local/include and should come before
       the fixincludes-fixed header files.  */
    { LOCAL_INCLUDE_DIR, 0, 0, 1 },
#endif
#ifdef TOOL_INCLUDE_DIR
    /* This is here ahead of GCC_INCLUDE_DIR because assert.h goes here.
       Likewise, behind LOCAL_INCLUDE_DIR, where glibc puts its assert.h.  */
    { TOOL_INCLUDE_DIR, "BINUTILS", 0, 1 },
#endif
    /* This is the dir for fixincludes.  Put it just before
       the files that we fix.  */
    { GCC_INCLUDE_DIR, "GCC", 0, 0 },
    /* Some systems have an extra dir of include files.  */
#ifdef SYSTEM_INCLUDE_DIR
    { SYSTEM_INCLUDE_DIR, 0, 0, 0 },
#endif
#ifndef STANDARD_INCLUDE_COMPONENT
#define STANDARD_INCLUDE_COMPONENT 0
#endif
    { STANDARD_INCLUDE_DIR, STANDARD_INCLUDE_COMPONENT, 0, 0 },
#endif /* not CROSS_COMPILE */
    { 0, 0, 0, 0 }
    };
#endif /* no INCLUDE_DEFAULTS */

/* `struct directive' defines one #-directive, including how to handle it.  */

struct directive {
  int length;			/* Length of name */
  int (*func)();		/* Function to handle directive */
  char *name;			/* Name of directive */
  enum node_type type;		/* Code which describes which directive.  */
  char command_reads_line;      /* One if rest of line is read by func.  */
};

#define IS_INCLUDE_DIRECTIVE_TYPE(t) (T_INCLUDE <= (t) && (t) <= T_IMPORT)

/* Here is the actual list of #-directives, most-often-used first.
   The initialize_builtins function assumes #define is the very first.  */

static struct directive directive_table[] = {
  {  6, do_define, "define", T_DEFINE},
  {  5, do_xifdef, "ifdef", T_IFDEF, 1},
  {  6, do_xifdef, "ifndef", T_IFNDEF, 1},
  {  7, do_include, "include", T_INCLUDE, 1},
  { 12, do_include, "include_next", T_INCLUDE_NEXT, 1},
  {  6, do_include, "import", T_IMPORT, 1},
  {  5, do_endif, "endif", T_ENDIF, 1},
  {  4, do_else, "else", T_ELSE, 1},
  {  2, do_if, "if", T_IF, 1},
  {  4, do_elif, "elif", T_ELIF, 1},
  {  5, do_undef, "undef", T_UNDEF},
  {  5, do_error, "error", T_ERROR},
  {  7, do_warning, "warning", T_WARNING},
  {  6, do_pragma, "pragma", T_PRAGMA},
  {  4, do_line, "line", T_LINE, 1},
  {  5, do_ident, "ident", T_IDENT, 1},
#ifdef SCCS_DIRECTIVE
  {  4, do_sccs, "sccs", T_SCCS},
#endif
  {  6, do_assert, "assert", T_ASSERT, 1},
  {  8, do_unassert, "unassert", T_UNASSERT, 1},
  {  -1, 0, "", T_UNUSED},
};

/* table to tell if char can be part of a C identifier.  */
U_CHAR is_idchar[256];
/* table to tell if char can be first char of a c identifier.  */
U_CHAR is_idstart[256];
/* table to tell if c is horizontal space.  */
U_CHAR is_hor_space[256];
/* table to tell if c is horizontal or vertical space.  */
static U_CHAR is_space[256];

/* Initialize syntactic classifications of characters.  */

static void
initialize_char_syntax (opts)
     struct cpp_options *opts;
{
  register int i;

  /*
   * Set up is_idchar and is_idstart tables.  These should be
   * faster than saying (is_alpha (c) || c == '_'), etc.
   * Set up these things before calling any routines tthat
   * refer to them.
   */
  for (i = 'a'; i <= 'z'; i++) {
    is_idchar[i - 'a' + 'A'] = 1;
    is_idchar[i] = 1;
    is_idstart[i - 'a' + 'A'] = 1;
    is_idstart[i] = 1;
  }
  for (i = '0'; i <= '9'; i++)
    is_idchar[i] = 1;
  is_idchar['_'] = 1;
  is_idstart['_'] = 1;
  is_idchar['$'] = opts->dollars_in_ident;
  is_idstart['$'] = opts->dollars_in_ident;

  /* horizontal space table */
  is_hor_space[' '] = 1;
  is_hor_space['\t'] = 1;
  is_hor_space['\v'] = 1;
  is_hor_space['\f'] = 1;
  is_hor_space['\r'] = 1;

  is_space[' '] = 1;
  is_space['\t'] = 1;
  is_space['\v'] = 1;
  is_space['\f'] = 1;
  is_space['\n'] = 1;
  is_space['\r'] = 1;
}


/* Place into PFILE a quoted string representing the string SRC.
   Caller must reserve enough space in pfile->token_buffer.  */

static void
quote_string (pfile, src)
     cpp_reader *pfile;