Adding upstream version 1.23.0.upstream/1.23.0upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 2039 insertions, 0 deletions

diff --git a/src/preproc/pic/lex.cpp b/src/preproc/pic/lex.cpp
new file mode 100644
index 0000000..e59801b
--- /dev/null
+++ b/src/preproc/pic/lex.cpp
@@ -0,0 +1,2039 @@
+// -*- C++ -*-
+/* Copyright (C) 1989-2020 Free Software Foundation, Inc.
+     Written by James Clark (jjc@jclark.com)
+
+This file is part of groff.
+
+groff 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 3 of the License, or
+(at your option) any later version.
+
+groff 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, see <http://www.gnu.org/licenses/>. */
+
+#include "pic.h"
+#include "ptable.h"
+#include "object.h"
+#include "pic.hpp"
+
+declare_ptable(char)
+implement_ptable(char)
+
+PTABLE(char) macro_table;
+
+// First character of the range representing $1-$<MAX_ARG>.
+// All of them must be invalid input characters.
+#ifndef IS_EBCDIC_HOST
+#define ARG1 0x80
+#define MAX_ARG 32
+#else
+#define ARG1 0x30
+#define MAX_ARG 16
+#endif
+
+class macro_input : public input {
+  char *s;
+  char *p;
+public:
+  macro_input(const char *);
+  ~macro_input();
+  int get();
+  int peek();
+};
+
+class argument_macro_input : public input {
+  char *s;
+  char *p;
+  char *ap;
+  int argc;
+  char *argv[MAX_ARG];
+public:
+  argument_macro_input(const char *, int, char **);
+  ~argument_macro_input();
+  int get();
+  int peek();
+};
+
+input::input() : next(0)
+{
+}
+
+input::~input()
+{
+}
+
+int input::get_location(const char **, int *)
+{
+  return 0;
+}
+
+file_input::file_input(FILE *f, const char *fn)
+: fp(f), filename(fn), lineno(0), ptr("")
+{
+}
+
+file_input::~file_input()
+{
+  fclose(fp);
+}
+
+int file_input::read_line()
+{
+  for (;;) {
+    line.clear();
+    lineno++;
+    for (;;) {
+      int c = getc(fp);
+      if (c == '\r') {
+	c = getc(fp);
+	if (c != '\n')
+	  lex_error("invalid input character code %1", '\r');
+      }
+      if (c == EOF)
+	break;
+      else if (is_invalid_input_char(c))
+	lex_error("invalid input character code %1", c);
+      else {
+	line += char(c);
+	if (c == '\n') 
+	  break;
+      }
+    }
+    if (line.length() == 0)
+      return 0;
+    if (!(line.length() >= 3 && line[0] == '.' && line[1] == 'P'
+	  && (line[2] == 'S' || line[2] == 'E' || line[2] == 'F')
+	  && (line.length() == 3 || line[3] == ' ' || line[3] == '\n'
+	      || compatible_flag))) {
+      line += '\0';
+      ptr = line.contents();
+      return 1;
+    }
+  }
+}
+
+int file_input::get()
+{
+  if (*ptr != '\0' || read_line())
+    return (unsigned char)*ptr++;
+  else
+    return EOF;
+}
+
+int file_input::peek()
+{
+  if (*ptr != '\0' || read_line())
+    return (unsigned char)*ptr;
+  else
+    return EOF;
+}
+
+int file_input::get_location(const char **fnp, int *lnp)
+{
+  *fnp = filename;
+  *lnp = lineno;
+  return 1;
+}
+
+macro_input::macro_input(const char *str)
+{
+  p = s = strsave(str);
+}
+
+macro_input::~macro_input()
+{
+  free(s);
+}
+
+int macro_input::get()
+{
+  if (p == 0 || *p == '\0')
+    return EOF;
+  else
+    return (unsigned char)*p++;
+}
+
+int macro_input::peek()
+{
+  if (p == 0 || *p == '\0')
+    return EOF;
+  else
+    return (unsigned char)*p;
+}
+
+char *process_body(const char *body)
+{
+  char *s = strsave(body);
+  int j = 0;
+  for (int i = 0; s[i] != '\0'; i++)
+    if (s[i] == '$' && csdigit(s[i + 1])) {
+      int n = 0;
+      int start = i;
+      i++;
+      while (csdigit(s[i]))
+	if (n > MAX_ARG)
+	  i++;
+	else
+	  n = 10 * n + s[i++] - '0';
+      if (n > MAX_ARG) {
+	string arg;
+	for (int k = start; k < i; k++)
+	  arg += s[k];
+	lex_error("invalid macro argument number %1", arg.contents());
+      }
+      else if (n > 0)
+	s[j++] = ARG1 + n - 1;
+      i--;
+    }
+    else
+      s[j++] = s[i];
+  s[j] = '\0';
+  return s;
+}
+
+argument_macro_input::argument_macro_input(const char *body, int ac, char **av)
+: ap(0), argc(ac)
+{
+  for (int i = 0; i < argc; i++)
+    argv[i] = av[i];
+  p = s = process_body(body);
+}
+
+argument_macro_input::~argument_macro_input()
+{
+  for (int i = 0; i < argc; i++)
+    free(argv[i]);
+  free(s);
+}
+
+int argument_macro_input::get()
+{
+  if (ap) {
+    if (*ap != '\0')
+      return (unsigned char)*ap++;
+    ap = 0;
+  }
+  if (p == 0)
+    return EOF;
+  while ((unsigned char)*p >= ARG1 
+	 && (unsigned char)*p <= ARG1 + MAX_ARG - 1) {
+    int i = (unsigned char)*p++ - ARG1;
+    if (i < argc && argv[i] != 0 && argv[i][0] != '\0') {
+      ap = argv[i];
+      return (unsigned char)*ap++;
+    }
+  }
+  if (*p == '\0')
+    return EOF;
+  return (unsigned char)*p++;
+}
+
+int argument_macro_input::peek()
+{
+  if (ap) {
+    if (*ap != '\0')
+      return (unsigned char)*ap;
+    ap = 0;
+  }
+  if (p == 0)
+    return EOF;
+  while ((unsigned char)*p >= ARG1
+	 && (unsigned char)*p <= ARG1 + MAX_ARG - 1) {
+    int i = (unsigned char)*p++ - ARG1;
+    if (i < argc && argv[i] != 0 && argv[i][0] != '\0') {
+      ap = argv[i];
+      return (unsigned char)*ap;
+    }
+  }
+  if (*p == '\0')
+    return EOF;
+  return (unsigned char)*p;
+}
+
+class input_stack {
+  static input *current_input;
+  static int bol_flag;
+public:
+  static void push(input *);
+  static void clear();
+  static int get_char();
+  static int peek_char();
+  static int get_location(const char **fnp, int *lnp);
+  static void push_back(unsigned char c, int was_bol = 0);
+  static int bol();
+};
+
+input *input_stack::current_input = 0;
+int input_stack::bol_flag = 0;
+
+inline int input_stack::bol()
+{
+  return bol_flag;
+}
+
+void input_stack::clear()
+{
+  while (current_input != 0) {
+    input *tem = current_input;
+    current_input = current_input->next;
+    delete tem;
+  }
+  bol_flag = 1;
+}
+
+void input_stack::push(input *in)
+{
+  in->next = current_input;
+  current_input = in;
+}
+
+void lex_init(input *top)
+{
+  input_stack::clear();
+  input_stack::push(top);
+}
+
+void lex_cleanup()
+{
+  while (input_stack::get_char() != EOF)
+    ;
+}
+
+int input_stack::get_char()
+{
+  while (current_input != 0) {
+    int c = current_input->get();
+    if (c != EOF) {
+      bol_flag = c == '\n';
+      return c;
+    }
+    // don't pop the top-level input off the stack
+    if (current_input->next == 0)
+      return EOF;
+    input *tem = current_input;
+    current_input = current_input->next;
+    delete tem;
+  }
+  return EOF;
+}
+
+int input_stack::peek_char()
+{
+  while (current_input != 0) {
+    int c = current_input->peek();
+    if (c != EOF)
+      return c;
+    if (current_input->next == 0)
+      return EOF;
+    input *tem = current_input;
+    current_input = current_input->next;
+    delete tem;
+  }
+  return EOF;
+}
+
+class char_input : public input {
+  int c;
+public:
+  char_input(int);
+  int get();
+  int peek();
+};
+
+char_input::char_input(int n) : c((unsigned char)n)
+{
+}
+
+int char_input::get()
+{
+  int n = c;
+  c = EOF;
+  return n;
+}
+
+int char_input::peek()
+{
+  return c;
+}
+
+void input_stack::push_back(unsigned char c, int was_bol)
+{
+  push(new char_input(c));
+  bol_flag = was_bol;
+}
+
+int input_stack::get_location(const char **fnp, int *lnp)
+{
+  for (input *p = current_input; p; p = p->next)
+    if (p->get_location(fnp, lnp))
+      return 1;
+  return 0;
+}
+
+string context_buffer;
+
+string token_buffer;
+double token_double;
+int token_int;
+
+void interpolate_macro_with_args(const char *body)
+{
+  char *argv[MAX_ARG];
+  int argc = 0;
+  int ignore = 0;
+  int i;
+  for (i = 0; i < MAX_ARG; i++)
+    argv[i] = 0;
+  int level = 0;
+  int c;
+  enum { NORMAL, IN_STRING, IN_STRING_QUOTED } state = NORMAL;
+  do {
+    token_buffer.clear();
+    for (;;) {
+      c = input_stack::get_char();
+      if (c == EOF) {
+	lex_error("end of input while scanning macro arguments");
+	break;
+      }
+      if (state == NORMAL && level == 0 && (c == ',' || c == ')')) {
+	if (token_buffer.length() > 0) {
+	  token_buffer +=  '\0';
+	  if (!ignore) {
+	    if (argc == MAX_ARG) {
+	      lex_warning("only %1 macro arguments supported", MAX_ARG);
+	      ignore = 1;
+	    }
+	    else
+	      argv[argc] = strsave(token_buffer.contents());
+	  }
+	}
+	// for 'foo()', argc = 0
+	if (argc > 0 || c != ')' || i > 0)
+	  if (!ignore)
+	    argc++;
+	break;
+      }
+      token_buffer += char(c);
+      switch (state) {
+      case NORMAL:
+	if (c == '"')
+	  state = IN_STRING;
+	else if (c == '(')
+	  level++;
+	else if (c == ')')
+	  level--;
+	break;
+      case IN_STRING:
+	if (c == '"')
+	  state = NORMAL;
+	else if (c == '\\')
+	  state = IN_STRING_QUOTED;
+	break;
+      case IN_STRING_QUOTED:
+	state = IN_STRING;
+	break;
+      }
+    }
+  } while (c != ')' && c != EOF);
+  input_stack::push(new argument_macro_input(body, argc, argv));
+}
+
+static int docmp(const char *s1, int n1, const char *s2, int n2)
+{
+  if (n1 < n2) {
+    int r = memcmp(s1, s2, n1);
+    return r ? r : -1;
+  }
+  else if (n1 > n2) {
+    int r = memcmp(s1, s2, n2);
+    return r ? r : 1;
+  }
+  else
+    return memcmp(s1, s2, n1);
+}
+
+int lookup_keyword(const char *str, int len)
+{
+  static struct keyword {
+    const char *name;
+    int token;
+  } table[] = {
+    { "Here", HERE },
+    { "above", ABOVE },
+    { "aligned", ALIGNED },
+    { "and", AND },
+    { "arc", ARC },
+    { "arrow", ARROW },
+    { "at", AT },
+    { "atan2", ATAN2 },
+    { "below", BELOW },
+    { "between", BETWEEN },
+    { "bottom", BOTTOM },
+    { "box", BOX },
+    { "by", BY },
+    { "ccw", CCW },
+    { "center", CENTER },
+    { "chop", CHOP },
+    { "circle", CIRCLE },
+    { "color", COLORED },
+    { "colored", COLORED },
+    { "colour", COLORED },
+    { "coloured", COLORED },
+    { "command", COMMAND },
+    { "copy", COPY },
+    { "cos", COS },
+    { "cw", CW },
+    { "dashed", DASHED },
+    { "define", DEFINE },
+    { "diam", DIAMETER },
+    { "diameter", DIAMETER },
+    { "do", DO },
+    { "dotted", DOTTED },
+    { "down", DOWN },
+    { "east", EAST },
+    { "ellipse", ELLIPSE },
+    { "else", ELSE },
+    { "end", END },
+    { "exp", EXP },
+    { "figname", FIGNAME },
+    { "fill", FILL },
+    { "filled", FILL },
+    { "for", FOR },
+    { "from", FROM },
+    { "height", HEIGHT },
+    { "ht", HEIGHT },
+    { "if", IF },
+    { "int", INT },
+    { "invis", INVISIBLE },
+    { "invisible", INVISIBLE },
+    { "last", LAST },
+    { "left", LEFT },
+    { "line", LINE },
+    { "ljust", LJUST },
+    { "log", LOG },
+    { "lower", LOWER },
+    { "max", K_MAX },
+    { "min", K_MIN },
+    { "move", MOVE },
+    { "north", NORTH },
+    { "of", OF },
+    { "outline", OUTLINED },
+    { "outlined", OUTLINED },
+    { "plot", PLOT },
+    { "print", PRINT },
+    { "rad", RADIUS },
+    { "radius", RADIUS },
+    { "rand", RAND },
+    { "reset", RESET },
+    { "right", RIGHT },
+    { "rjust", RJUST },
+    { "same", SAME },
+    { "sh", SH },
+    { "shaded", SHADED },
+    { "sin", SIN },
+    { "solid", SOLID },
+    { "south", SOUTH },
+    { "spline", SPLINE },
+    { "sprintf", SPRINTF },
+    { "sqrt", SQRT },
+    { "srand", SRAND },
+    { "start", START },
+    { "the", THE },
+    { "then", THEN },
+    { "thick", THICKNESS },
+    { "thickness", THICKNESS },
+    { "thru", THRU },
+    { "to", TO },
+    { "top", TOP },
+    { "undef", UNDEF },
+    { "until", UNTIL },
+    { "up", UP },
+    { "upper", UPPER },
+    { "way", WAY },
+    { "west", WEST },
+    { "wid", WIDTH },
+    { "width", WIDTH },
+    { "with", WITH },
+    { "xslanted", XSLANTED },
+    { "yslanted", YSLANTED },
+  };
+  
+  const keyword *start = table;
+  const keyword *end = table + sizeof(table)/sizeof(table[0]);
+  while (start < end) {
+    // start <= target < end
+    const keyword *mid = start + (end - start)/2;
+    
+    int cmp = docmp(str, len, mid->name, strlen(mid->name));
+    if (cmp == 0)
+      return mid->token;
+    if (cmp < 0)
+      end = mid;
+    else
+      start = mid + 1;
+  }
+  return 0;
+}
+
+int get_token_after_dot(int c)
+{
+  // get_token deals with the case where c is a digit
+  switch (c) {
+  case 'h':
+    input_stack::get_char();
+    c = input_stack::peek_char();
+    if (c == 't') {
+      input_stack::get_char();
+      context_buffer = ".ht";
+      return DOT_HT;
+    }
+    else if (c == 'e') {
+      input_stack::get_char();
+      c = input_stack::peek_char();
+      if (c == 'i') {
+	input_stack::get_char();
+	c = input_stack::peek_char();
+	if (c == 'g') {
+	  input_stack::get_char();
+	  c = input_stack::peek_char();
+	  if (c == 'h') {
+	    input_stack::get_char();
+	    c = input_stack::peek_char();
+	    if (c == 't') {
+	      input_stack::get_char();
+	      context_buffer = ".height";
+	      return DOT_HT;
+	    }
+	    input_stack::push_back('h');
+	  }
+	  input_stack::push_back('g');
+	}
+	input_stack::push_back('i');
+      }
+      input_stack::push_back('e');
+    }
+    input_stack::push_back('h');
+    return '.';
+  case 'x':
+    input_stack::get_char();
+    context_buffer = ".x";
+    return DOT_X;
+  case 'y':
+    input_stack::get_char();
+    context_buffer = ".y";
+    return DOT_Y;
+  case 'c':
+    input_stack::get_char();
+    c = input_stack::peek_char();
+    if (c == 'e') {
+      input_stack::get_char();
+      c = input_stack::peek_char();
+      if (c == 'n') {
+	input_stack::get_char();
+	c = input_stack::peek_char();
+	if (c == 't') {
+	  input_stack::get_char();
+	  c = input_stack::peek_char();
+	  if (c == 'e') {
+	    input_stack::get_char();
+	    c = input_stack::peek_char();
+	    if (c == 'r') {
+	      input_stack::get_char();
+	      context_buffer = ".center";
+	      return DOT_C;
+	    }
+	    input_stack::push_back('e');
+	  }
+	  input_stack::push_back('t');
+	}
+	input_stack::push_back('n');
+      }
+      input_stack::push_back('e');
+    }
+    context_buffer = ".c";
+    return DOT_C;
+  case 'n':
+    input_stack::get_char();
+    c = input_stack::peek_char();
+    if (c == 'e') {
+      input_stack::get_char();
+      context_buffer = ".ne";
+      return DOT_NE;
+    }
+    else if (c == 'w') {
+      input_stack::get_char();
+      context_buffer = ".nw";
+      return DOT_NW;
+    }
+    else {
+      context_buffer = ".n";
+      return DOT_N;
+    }
+    break;
+  case 'e':
+    input_stack::get_char();
+    c = input_stack::peek_char();
+    if (c == 'n') {
+      input_stack::get_char();
+      c = input_stack::peek_char();
+      if (c == 'd') {
+	input_stack::get_char();
+	context_buffer = ".end";
+	return DOT_END;
+      }
+      input_stack::push_back('n');
+      context_buffer = ".e";
+      return DOT_E;
+    }
+    context_buffer = ".e";
+    return DOT_E;
+  case 'w':
+    input_stack::get_char();
+    c = input_stack::peek_char();
+    if (c == 'i') {
+      input_stack::get_char();
+      c = input_stack::peek_char();
+      if (c == 'd') {
+	input_stack::get_char();
+	c = input_stack::peek_char();
+	if (c == 't') {
+	  input_stack::get_char();
+	  c = input_stack::peek_char();
+	  if (c == 'h') {
+	    input_stack::get_char();
+	    context_buffer = ".width";
+	    return DOT_WID;
+	  }
+	  input_stack::push_back('t');
+	}
+	context_buffer = ".wid";
+	return DOT_WID;
+      }
+      input_stack::push_back('i');
+    }
+    context_buffer = ".w";
+    return DOT_W;
+  case 's':
+    input_stack::get_char();
+    c = input_stack::peek_char();
+    if (c == 'e') {
+      input_stack::get_char();
+      context_buffer = ".se";
+      return DOT_SE;
+    }
+    else if (c == 'w') {
+      input_stack::get_char();
+      context_buffer = ".sw";
+      return DOT_SW;
+    }
+    else {
+      if (c == 't') {
+	input_stack::get_char();
+	c = input_stack::peek_char();
+	if (c == 'a') {
+	  input_stack::get_char();
+	  c = input_stack::peek_char();
+	  if (c == 'r') {
+	    input_stack::get_char();
+	    c = input_stack::peek_char();
+	    if (c == 't') {
+	      input_stack::get_char();
+	      context_buffer = ".start";
+	      return DOT_START;
+	    }
+	    input_stack::push_back('r');
+	  }
+	  input_stack::push_back('a');
+	}
+	input_stack::push_back('t');
+      }
+      context_buffer = ".s";
+      return DOT_S;
+    }
+    break;
+  case 't':
+    input_stack::get_char();
+    c = input_stack::peek_char();
+    if (c == 'o') {
+      input_stack::get_char();
+      c = input_stack::peek_char();
+      if (c == 'p') {
+	input_stack::get_char();
+	context_buffer = ".top";
+	return DOT_N;
+      }
+      input_stack::push_back('o');
+    }
+    context_buffer = ".t";
+    return DOT_N;
+  case 'l':
+    input_stack::get_char();
+    c = input_stack::peek_char();
+    if (c == 'e') {
+      input_stack::get_char();
+      c = input_stack::peek_char();
+      if (c == 'f') {
+	input_stack::get_char();
+	c = input_stack::peek_char();
+	if (c == 't') {
+	  input_stack::get_char();
+	  context_buffer = ".left";
+	  return DOT_W;
+	}
+	input_stack::push_back('f');
+      }
+      input_stack::push_back('e');
+    }
+    context_buffer = ".l";
+    return DOT_W;
+  case 'r':
+    input_stack::get_char();
+    c = input_stack::peek_char();
+    if (c == 'a') {
+      input_stack::get_char();
+      c = input_stack::peek_char();
+      if (c == 'd') {
+	input_stack::get_char();
+	context_buffer = ".rad";
+	return DOT_RAD;
+      }
+      input_stack::push_back('a');
+    }
+    else if (c == 'i') {
+      input_stack::get_char();
+      c = input_stack::peek_char();
+      if (c == 'g') {
+	input_stack::get_char();
+	c = input_stack::peek_char();
+	if (c == 'h') {
+	  input_stack::get_char();
+	  c = input_stack::peek_char();
+	  if (c == 't') {
+	    input_stack::get_char();
+	    context_buffer = ".right";
+	    return DOT_E;
+	  }
+	  input_stack::push_back('h');
+	}
+	input_stack::push_back('g');
+      }
+      input_stack::push_back('i');
+    }
+    context_buffer = ".r";
+    return DOT_E;
+  case 'b':
+    input_stack::get_char();
+    c = input_stack::peek_char();
+    if (c == 'o') {
+      input_stack::get_char();
+      c = input_stack::peek_char();
+      if (c == 't') {
+	input_stack::get_char();
+	c = input_stack::peek_char();
+	if (c == 't') {
+	  input_stack::get_char();
+	  c = input_stack::peek_char();
+	  if (c == 'o') {
+	    input_stack::get_char();
+	    c = input_stack::peek_char();
+	    if (c == 'm') {
+	      input_stack::get_char();
+	      context_buffer = ".bottom";
+	      return DOT_S;
+	    }
+	    input_stack::push_back('o');
+	  }
+	  input_stack::push_back('t');
+	}
+	context_buffer = ".bot";
+	return DOT_S;
+      }
+      input_stack::push_back('o');
+    }
+    context_buffer = ".b";
+    return DOT_S;
+  default:
+    context_buffer = '.';
+    return '.';
+  }
+}
+
+int get_token(int lookup_flag)
+{
+  context_buffer.clear();
+  for (;;) {
+    int n = 0;
+    int bol = input_stack::bol();
+    int c = input_stack::get_char();
+    if (bol && c == command_char) {
+      token_buffer.clear();
+      token_buffer += c;
+      // the newline is not part of the token
+      for (;;) {
+	c = input_stack::peek_char();
+	if (c == EOF || c == '\n')
+	  break;
+	input_stack::get_char();
+	token_buffer += char(c);
+      }
+      context_buffer = token_buffer;
+      return COMMAND_LINE;
+    }
+    switch (c) {
+    case EOF:
+      return EOF;
+    case ' ':
+    case '\t':
+      break;
+    case '\\':
+      {
+	int d = input_stack::peek_char();
+	if (d != '\n') {
+	  context_buffer = '\\';
+	  return '\\';
+	}
+	input_stack::get_char();
+	break;
+      }
+    case '#':
+      do {
+	c = input_stack::get_char();
+      } while (c != '\n' && c != EOF);
+      if (c == '\n')
+	context_buffer = '\n';
+      return c;
+    case '"':
+      context_buffer = '"';
+      token_buffer.clear();
+      for (;;) {
+	c = input_stack::get_char();
+	if (c == '\\') {
+	  context_buffer += '\\';
+	  c = input_stack::peek_char();
+	  if (c == '"') {
+	    input_stack::get_char();
+	    token_buffer += '"';
+	    context_buffer += '"';
+	  }
+	  else
+	    token_buffer += '\\';
+	}
+	else if (c == '\n') {
+	  error("newline in string");
+	  break;
+	}
+	else if (c == EOF) {
+	  error("missing '\"'");
+	  break;
+	}
+	else if (c == '"') {
+	  context_buffer += '"';
+	  break;
+	}
+	else {
+	  context_buffer += char(c);
+	  token_buffer += char(c);
+	}
+      }
+      return TEXT;
+    case '0':
+    case '1':
+    case '2':
+    case '3':
+    case '4':
+    case '5':
+    case '6':
+    case '7':
+    case '8':
+    case '9':
+      {   
+	int overflow = 0;
+	n = 0;
+	for (;;) {
+	  if (n > (INT_MAX - 9)/10) {
+	    overflow = 1;
+	    break;
+	  }
+	  n *= 10;
+	  n += c - '0';
+	  context_buffer += char(c);
+	  c = input_stack::peek_char();
+	  if (c == EOF || !csdigit(c))
+	    break;
+	  c = input_stack::get_char();
+	}
+	token_double = n;
+	if (overflow) {
+	  for (;;) {
+	    token_double *= 10.0;
+	    token_double += c - '0';
+	    context_buffer += char(c);
+	    c = input_stack::peek_char();
+	    if (c == EOF || !csdigit(c))
+	      break;
+	    c = input_stack::get_char();
+	  }
+	  // if somebody asks for 1000000000000th, we will silently
+	  // give them INT_MAXth
+	  double temp = token_double; // work around gas 1.34/sparc bug
+	  if (token_double > INT_MAX)
+	    n = INT_MAX;
+	  else
+	    n = int(temp);
+	}
+      }
+      switch (c) {
+      case 'i':
+      case 'I':
+	context_buffer += char(c);
+	input_stack::get_char();
+	return NUMBER;
+      case '.':
+	{
+	  context_buffer += '.';
+	  input_stack::get_char();
+	got_dot:
+	  double factor = 1.0;
+	  for (;;) {
+	    c = input_stack::peek_char();
+	    if (c == EOF || !csdigit(c))
+	      break;
+	    input_stack::get_char();
+	    context_buffer += char(c);
+	    factor /= 10.0;
+	    if (c != '0')
+	      token_double += factor*(c - '0');
+	  }
+	  if (c != 'e' && c != 'E') {
+	    if (c == 'i' || c == 'I') {
+	      context_buffer += char(c);
+	      input_stack::get_char();
+	    }
+	    return NUMBER;
+	  }
+	}
+	// fall through
+      case 'e':
+      case 'E':
+	{
+	  int echar = c;
+	  input_stack::get_char();
+	  c = input_stack::peek_char();
+	  int sign = '+';
+	  if (c == '+' || c == '-') {
+	    sign = c;
+	    input_stack::get_char();
+	    c = input_stack::peek_char();
+	    if (c == EOF || !csdigit(c)) {
+	      input_stack::push_back(sign);
+	      input_stack::push_back(echar);
+	      return NUMBER;
+	    }
+	    context_buffer += char(echar);
+	    context_buffer += char(sign);
+	  }
+	  else {
+	    if (c == EOF || !csdigit(c)) {
+	      input_stack::push_back(echar);
+	      return NUMBER;
+	    }
+	    context_buffer += char(echar);
+	  }
+	  input_stack::get_char();
+	  context_buffer += char(c);
+	  n = c - '0';
+	  for (;;) {
+	    c = input_stack::peek_char();
+	    if (c == EOF || !csdigit(c))
+	      break;
+	    input_stack::get_char();
+	    context_buffer += char(c);
+	    n = n*10 + (c - '0');
+	  }
+	  if (sign == '-')
+	    n = -n;
+	  if (c == 'i' || c == 'I') {
+	    context_buffer += char(c);
+	    input_stack::get_char();
+	  }
+	  token_double *= pow(10.0, n);
+	  return NUMBER;
+	}
+      case 'n':
+	input_stack::get_char();
+	c = input_stack::peek_char();
+	if (c == 'd') {
+	  input_stack::get_char();
+	  token_int = n;
+	  context_buffer += "nd";
+	  return ORDINAL;
+	}
+	input_stack::push_back('n');
+	return NUMBER;
+      case 'r':
+	input_stack::get_char();
+	c = input_stack::peek_char();
+	if (c == 'd') {
+	  input_stack::get_char();
+	  token_int = n;
+	  context_buffer += "rd";
+	  return ORDINAL;
+	}
+	input_stack::push_back('r');
+	return NUMBER;
+      case 't':
+	input_stack::get_char();
+	c = input_stack::peek_char();
+	if (c == 'h') {
+	  input_stack::get_char();
+	  token_int = n;
+	  context_buffer += "th";
+	  return ORDINAL;
+	}
+	input_stack::push_back('t');
+	return NUMBER;
+      case 's':
+	input_stack::get_char();
+	c = input_stack::peek_char();
+	if (c == 't') {
+	  input_stack::get_char();
+	  token_int = n;
+	  context_buffer += "st";
+	  return ORDINAL;
+	}
+	input_stack::push_back('s');
+	return NUMBER;
+      default:
+	return NUMBER;
+      }
+      break;
+    case '\'':
+      {
+	c = input_stack::peek_char();
+	if (c == 't') {
+	  input_stack::get_char();
+	  c = input_stack::peek_char();
+	  if (c == 'h') {
+	    input_stack::get_char();
+	    context_buffer = "'th";
+	    return TH;
+	  }
+	  else
+	    input_stack::push_back('t');
+	}
+	context_buffer = "'";
+	return '\'';
+      }
+    case '.':
+      {
+	c = input_stack::peek_char();
+	if (c != EOF && csdigit(c)) {
+	  n = 0;
+	  token_double = 0.0;
+	  context_buffer = '.';
+	  goto got_dot;
+	}
+	return get_token_after_dot(c);
+      }
+    case '<':
+      c = input_stack::peek_char();
+      if (c == '-') {
+	input_stack::get_char();
+	c = input_stack::peek_char();
+	if (c == '>') {
+	  input_stack::get_char();
+	  context_buffer = "<->";
+	  return DOUBLE_ARROW_HEAD;
+	}
+	context_buffer = "<-";
+	return LEFT_ARROW_HEAD;
+      }
+      else if (c == '=') {
+	input_stack::get_char();
+	context_buffer = "<=";
+	return LESSEQUAL;
+      }
+      context_buffer = "<";
+      return '<';
+    case '-':
+      c = input_stack::peek_char();
+      if (c == '>') {
+	input_stack::get_char();
+	context_buffer = "->";
+	return RIGHT_ARROW_HEAD;
+      }
+      context_buffer = "-";
+      return '-';
+    case '!':
+      c = input_stack::peek_char();
+      if (c == '=') {
+	input_stack::get_char();
+	context_buffer = "!=";
+	return NOTEQUAL;
+      }
+      context_buffer = "!";
+      return '!';
+    case '>':
+      c = input_stack::peek_char();
+      if (c == '=') {
+	input_stack::get_char();
+	context_buffer = ">=";
+	return GREATEREQUAL;
+      }
+      context_buffer = ">";
+      return '>';
+    case '=':
+      c = input_stack::peek_char();
+      if (c == '=') {
+	input_stack::get_char();
+	context_buffer = "==";
+	return EQUALEQUAL;
+      }
+      context_buffer = "=";
+      return '=';
+    case '&':
+      c = input_stack::peek_char();
+      if (c == '&') {
+	input_stack::get_char();
+	context_buffer = "&&";
+	return ANDAND;
+      }
+      context_buffer = "&";
+      return '&';
+    case '|':
+      c = input_stack::peek_char();
+      if (c == '|') {
+	input_stack::get_char();
+	context_buffer = "||";
+	return OROR;
+      }
+      context_buffer = "|";
+      return '|';
+    default:
+      if (c != EOF && csalpha(c)) {
+	token_buffer.clear();
+	token_buffer = c;
+	for (;;) {
+	  c = input_stack::peek_char();
+	  if (c == EOF || (!csalnum(c) && c != '_'))
+	    break;
+	  input_stack::get_char();
+	  token_buffer += char(c);
+	}
+	int tok = lookup_keyword(token_buffer.contents(),
+				 token_buffer.length());
+	if (tok != 0) {
+	  context_buffer = token_buffer;
+	  return tok;
+	}
+	char *def = 0;
+	if (lookup_flag) {
+	  token_buffer += '\0';
+	  def = macro_table.lookup(token_buffer.contents());
+	  token_buffer.set_length(token_buffer.length() - 1);
+	  if (def) {
+	    if (c == '(') {
+	      input_stack::get_char();
+	      interpolate_macro_with_args(def);
+	    }
+	    else
+	      input_stack::push(new macro_input(def));
+	  }
+	}
+	if (!def) {
+	  context_buffer = token_buffer;
+	  if (csupper(token_buffer[0]))
+	    return LABEL;
+	  else
+	    return VARIABLE;
+	}
+      }
+      else {
+	context_buffer = char(c);
+	return (unsigned char)c;
+      }
+      break;
+    }
+  }
+}
+
+int get_delimited()
+{
+  token_buffer.clear();
+  int c = input_stack::get_char();
+  while (c == ' ' || c == '\t' || c == '\n')
+    c = input_stack::get_char();
+  if (c == EOF) {
+    lex_error("missing delimiter");
+    return 0;
+  }
+  context_buffer = char(c);
+  int had_newline = 0;
+  int start = c;
+  int level = 0;
+  enum { NORMAL, IN_STRING, IN_STRING_QUOTED, DELIM_END } state = NORMAL;
+  for (;;) {
+    c = input_stack::get_char();
+    if (c == EOF) {
+      lex_error("missing closing delimiter");
+      return 0;
+    }
+    if (c == '\n')
+      had_newline = 1;
+    else if (!had_newline)
+      context_buffer += char(c);
+    switch (state) {
+    case NORMAL:
+      if (start == '{') {
+	if (c == '{') {
+	  level++;
+	  break;
+	}
+	if (c == '}') {
+	  if (--level < 0)
+	    state = DELIM_END;
+	  break;
+	}
+      }
+      else {
+	if (c == start) {
+	  state = DELIM_END;
+	  break;
+	}
+      }
+      if (c == '"')
+	state = IN_STRING;
+      break;
+    case IN_STRING_QUOTED:
+      if (c == '\n')
+	state = NORMAL;
+      else
+	state = IN_STRING;
+      break;
+    case IN_STRING:
+      if (c == '"' || c == '\n')
+	state = NORMAL;
+      else if (c == '\\')
+	state = IN_STRING_QUOTED;
+      break;
+    case DELIM_END:
+      // This case it just to shut cfront 2.0 up.
+    default:
+      assert(0);
+    }
+    if (state == DELIM_END)
+      break;
+    token_buffer += c;
+  }
+  return 1;
+}
+
+void do_define()
+{
+  int t = get_token(0);		// do not expand what we are defining
+  if (t != VARIABLE && t != LABEL) {
+    lex_error("can only define variable or placename");
+    return;
+  }
+  token_buffer += '\0';
+  string nm = token_buffer;
+  const char *name = nm.contents();
+  if (!get_delimited())
+    return;
+  token_buffer += '\0';
+  macro_table.define(name, strsave(token_buffer.contents()));
+}
+
+void do_undef()
+{
+  int t = get_token(0);		// do not expand what we are undefining
+  if (t != VARIABLE && t != LABEL) {
+    lex_error("can only define variable or placename");
+    return;
+  }
+  token_buffer += '\0';
+  macro_table.define(token_buffer.contents(), 0);
+}
+
+
+class for_input : public input {
+  char *var;
+  char *body;
+  double from;
+  double to;
+  int by_is_multiplicative;
+  double by;
+  const char *p;
+  int done_newline;
+public:
+  for_input(char *, double, double, int, double, char *);
+  ~for_input();
+  int get();
+  int peek();
+};
+
+for_input::for_input(char *vr, double f, double t,
+		     int bim, double b, char *bd)
+: var(vr), body(bd), from(f), to(t), by_is_multiplicative(bim), by(b),
+  p(body), done_newline(0)
+{
+}
+
+for_input::~for_input()
+{
+  free(var);
+  free(body);
+}
+
+int for_input::get()
+{
+  if (p == 0)
+    return EOF;
+  for (;;) {
+    if (*p != '\0')
+      return (unsigned char)*p++;
+    if (!done_newline) {
+      done_newline = 1;
+      return '\n';
+    }
+    double val;
+    if (!lookup_variable(var, &val)) {
+      lex_error("body of 'for' terminated enclosing block");
+      return EOF;
+    }
+    if (by_is_multiplicative)
+      val *= by;
+    else
+      val += by;
+    define_variable(var, val);
+    if ((from <= to && val > to)
+	|| (from >= to && val < to)) {
+      p = 0;
+      return EOF;
+    }
+    p = body;
+    done_newline = 0;
+  }
+}
+
+int for_input::peek()
+{
+  if (p == 0)
+    return EOF;
+  if (*p != '\0')
+    return (unsigned char)*p;
+  if (!done_newline)
+    return '\n';
+  double val;
+  if (!lookup_variable(var, &val))
+    return EOF;
+  if (by_is_multiplicative) {
+    if (val * by > to)
+      return EOF;
+  }
+  else {
+    if ((from <= to && val + by > to)
+	|| (from >= to && val + by < to))
+      return EOF;
+  }
+  if (*body == '\0')
+    return EOF;
+  return (unsigned char)*body;
+}
+
+void do_for(char *var, double from, double to, int by_is_multiplicative,
+	    double by, char *body)
+{
+  define_variable(var, from);
+  if ((by_is_multiplicative && by <= 0)
+      || (by > 0 && from > to)
+      || (by < 0 && from < to))
+    return;
+  input_stack::push(new for_input(var, from, to,
+				  by_is_multiplicative, by, body));
+}
+
+
+void do_copy(const char *filename)
+{
+  errno = 0;
+  FILE *fp = fopen(filename, "r");
+  if (fp == 0) {
+    lex_error("can't open '%1': %2", filename, strerror(errno));
+    return;
+  }
+  input_stack::push(new file_input(fp, filename));
+}
+
+class copy_thru_input : public input {
+  int done;
+  char *body;
+  char *until;
+  const char *p;
+  const char *ap;
+  int argv[MAX_ARG];
+  int argc;
+  string line;
+  int get_line();
+  virtual int inget() = 0;
+public:
+  copy_thru_input(const char *b, const char *u);
+  ~copy_thru_input();
+  int get();
+  int peek();
+};
+
+class copy_file_thru_input : public copy_thru_input {
+  input *in;
+public:
+  copy_file_thru_input(input *, const char *b, const char *u);
+  ~copy_file_thru_input();
+  int inget();
+};
+
+copy_file_thru_input::copy_file_thru_input(input *i, const char *b,
+					   const char *u)
+: copy_thru_input(b, u), in(i)
+{
+}
+
+copy_file_thru_input::~copy_file_thru_input()
+{
+  delete in;
+}
+
+int copy_file_thru_input::inget()
+{
+  if (!in)
+    return EOF;
+  else
+    return in->get();
+}
+
+class copy_rest_thru_input : public copy_thru_input {
+public:
+  copy_rest_thru_input(const char *, const char *u);
+  int inget();
+};
+
+copy_rest_thru_input::copy_rest_thru_input(const char *b, const char *u)
+: copy_thru_input(b, u)
+{
+}
+
+int copy_rest_thru_input::inget()
+{
+  while (next != 0) {
+    int c = next->get();
+    if (c != EOF)
+      return c;
+    if (next->next == 0)
+      return EOF;
+    input *tem = next;
+    next = next->next;
+    delete tem;
+  }
+  return EOF;
+
+}
+
+copy_thru_input::copy_thru_input(const char *b, const char *u)
+: done(0)
+{
+  ap = 0;
+  body = process_body(b);
+  p = 0;
+  until = strsave(u);
+}
+
+
+copy_thru_input::~copy_thru_input()
+{
+  delete[] body;
+  delete[] until;
+}
+
+int copy_thru_input::get()
+{
+  if (ap) {
+    if (*ap != '\0')
+      return (unsigned char)*ap++;
+    ap = 0;
+  }
+  for (;;) {
+    if (p == 0) {
+      if (!get_line())
+	break;
+      p = body;
+    }
+    if (*p == '\0') {
+      p = 0;
+      return '\n';
+    }
+    while ((unsigned char)*p >= ARG1
+	   && (unsigned char)*p <= ARG1 + MAX_ARG - 1) {
+      int i = (unsigned char)*p++ - ARG1;
+      if (i < argc && line[argv[i]] != '\0') {
+	ap = line.contents() + argv[i];
+	return (unsigned char)*ap++;
+      }
+    }
+    if (*p != '\0')
+      return (unsigned char)*p++;
+  }
+  return EOF;
+}
+
+int copy_thru_input::peek()
+{
+  if (ap) {
+    if (*ap != '\0')
+      return (unsigned char)*ap;
+    ap = 0;
+  }
+  for (;;) {
+    if (p == 0) {
+      if (!get_line())
+	break;
+      p = body;
+    }
+    if (*p == '\0')
+      return '\n';
+    while ((unsigned char)*p >= ARG1
+	   && (unsigned char)*p <= ARG1 + MAX_ARG - 1) {
+      int i = (unsigned char)*p++ - ARG1;
+      if (i < argc && line[argv[i]] != '\0') {
+	ap = line.contents() + argv[i];
+	return (unsigned char)*ap;
+      }
+    }
+    if (*p != '\0')
+      return (unsigned char)*p;
+  }
+  return EOF;
+}
+
+int copy_thru_input::get_line()
+{
+  if (done)
+    return 0;
+  line.clear();
+  argc = 0;
+  int c = inget();
+  for (;;) {
+    while (c == ' ')
+      c = inget();
+    if (c == EOF || c == '\n')
+      break;
+    if (argc == MAX_ARG) {
+      do {
+	c = inget();
+      } while (c != '\n' && c != EOF);
+      break;
+    }
+    argv[argc++] = line.length();
+    do {
+      line += char(c);
+      c = inget();
+    } while (c != ' ' && c != '\n');
+    line += '\0';
+  }
+  if (until != 0 && argc > 0 && strcmp(&line[argv[0]], until) == 0) {
+    done = 1;
+    return 0;
+  }
+  return argc > 0 || c == '\n';
+}
+
+class simple_file_input : public input {
+  const char *filename;
+  int lineno;
+  FILE *fp;
+public:
+  simple_file_input(FILE *, const char *);
+  ~simple_file_input();
+  int get();
+  int peek();
+  int get_location(const char **, int *);
+};
+
+simple_file_input::simple_file_input(FILE *p, const char *s)
+: filename(s), lineno(1), fp(p)
+{
+}
+
+simple_file_input::~simple_file_input()
+{
+  // don't delete the filename
+  fclose(fp);
+}
+
+int simple_file_input::get()
+{
+  int c = getc(fp);
+  while (is_invalid_input_char(c)) {
+    error("invalid input character code %1", c);
+    c = getc(fp);
+  }
+  if (c == '\n')
+    lineno++;
+  return c;
+}
+
+int simple_file_input::peek()
+{
+  int c = getc(fp);
+  while (is_invalid_input_char(c)) {
+    error("invalid input character code %1", c);
+    c = getc(fp);
+  }
+  if (c != EOF)
+    ungetc(c, fp);
+  return c;
+}
+
+int simple_file_input::get_location(const char **fnp, int *lnp)
+{
+  *fnp = filename;
+  *lnp = lineno;
+  return 1;
+}
+
+
+void copy_file_thru(const char *filename, const char *body, const char *until)
+{
+  errno = 0;
+  FILE *fp = fopen(filename, "r");
+  if (fp == 0) {
+    lex_error("can't open '%1': %2", filename, strerror(errno));
+    return;
+  }
+  input *in = new copy_file_thru_input(new simple_file_input(fp, filename),
+				       body, until);
+  input_stack::push(in);
+}
+
+void copy_rest_thru(const char *body, const char *until)
+{
+  input_stack::push(new copy_rest_thru_input(body, until));
+}
+
+void push_body(const char *s)
+{
+  input_stack::push(new char_input('\n'));
+  input_stack::push(new macro_input(s));
+}
+
+int delim_flag = 0;
+
+char *get_thru_arg()
+{
+  int c = input_stack::peek_char();
+  while (c == ' ') {
+    input_stack::get_char();
+    c = input_stack::peek_char();
+  }
+  if (c != EOF && csalpha(c)) {
+    // looks like a macro
+    input_stack::get_char();
+    token_buffer = c;
+    for (;;) {
+      c = input_stack::peek_char();
+      if (c == EOF || (!csalnum(c) && c != '_'))
+	break;
+      input_stack::get_char();
+      token_buffer += char(c);
+    }
+    context_buffer = token_buffer;
+    token_buffer += '\0';
+    char *def = macro_table.lookup(token_buffer.contents());
+    if (def)
+      return strsave(def);
+    // I guess it wasn't a macro after all; so push the macro name back.
+    // -2 because we added a '\0'
+    for (int i = token_buffer.length() - 2; i >= 0; i--)
+      input_stack::push_back(token_buffer[i]);
+  }
+  if (get_delimited()) {
+    token_buffer += '\0';
+    return strsave(token_buffer.contents());
+  }
+  else
+    return 0;
+}
+
+int lookahead_token = -1;
+string old_context_buffer;
+
+void do_lookahead()
+{
+  if (lookahead_token == -1) {
+    old_context_buffer = context_buffer;
+    lookahead_token = get_token(1);
+  }
+}
+
+int yylex()
+{
+  if (delim_flag) {
+    assert(lookahead_token == -1);
+    if (delim_flag == 2) {
+      if ((yylval.str = get_thru_arg()) != 0)
+	return DELIMITED;
+      else
+	return 0;
+    }
+    else {
+      if (get_delimited()) {
+	token_buffer += '\0';
+	yylval.str = strsave(token_buffer.contents());
+	return DELIMITED;
+      }
+      else
+	return 0;
+    }
+  }
+  for (;;) {
+    int t;
+    if (lookahead_token >= 0) {
+      t = lookahead_token;
+      lookahead_token = -1;
+    }
+    else
+      t = get_token(1);
+    switch (t) {
+    case '\n':
+      return ';';
+    case EOF:
+      return 0;
+    case DEFINE:
+      do_define();
+      break;
+    case UNDEF:
+      do_undef();
+      break;
+    case ORDINAL:
+      yylval.n = token_int;
+      return t;
+    case NUMBER:
+      yylval.x = token_double;
+      return t;
+    case COMMAND_LINE:
+    case TEXT:
+      token_buffer += '\0';
+      if (!input_stack::get_location(&yylval.lstr.filename,
+				     &yylval.lstr.lineno)) {
+	yylval.lstr.filename = 0;
+	yylval.lstr.lineno = -1;
+      }
+      yylval.lstr.str = strsave(token_buffer.contents());
+      return t;
+    case LABEL:
+    case VARIABLE:
+      token_buffer += '\0';
+      yylval.str = strsave(token_buffer.contents());
+      return t;
+    case LEFT:
+      // change LEFT to LEFT_CORNER when followed by OF
+      old_context_buffer = context_buffer;
+      lookahead_token = get_token(1);
+      if (lookahead_token == OF)
+	return LEFT_CORNER;
+      else
+	return t;
+    case RIGHT:
+      // change RIGHT to RIGHT_CORNER when followed by OF
+      old_context_buffer = context_buffer;
+      lookahead_token = get_token(1);
+      if (lookahead_token == OF)
+	return RIGHT_CORNER;
+      else
+	return t;
+    case UPPER:
+      // recognise UPPER only before LEFT or RIGHT
+      old_context_buffer = context_buffer;
+      lookahead_token = get_token(1);
+      if (lookahead_token != LEFT && lookahead_token != RIGHT) {
+	yylval.str = strsave("upper");
+	return VARIABLE;
+      }
+      else
+	return t;
+    case LOWER:
+      // recognise LOWER only before LEFT or RIGHT
+      old_context_buffer = context_buffer;
+      lookahead_token = get_token(1);
+      if (lookahead_token != LEFT && lookahead_token != RIGHT) {
+	yylval.str = strsave("lower");
+	return VARIABLE;
+      }
+      else
+	return t;
+    case NORTH:
+      // recognise NORTH only before OF
+      old_context_buffer = context_buffer;
+      lookahead_token = get_token(1);
+      if (lookahead_token != OF) {
+	yylval.str = strsave("north");
+	return VARIABLE;
+      }
+      else
+	return t;
+    case SOUTH:
+      // recognise SOUTH only before OF
+      old_context_buffer = context_buffer;
+      lookahead_token = get_token(1);
+      if (lookahead_token != OF) {
+	yylval.str = strsave("south");
+	return VARIABLE;
+      }
+      else
+	return t;
+    case EAST:
+      // recognise EAST only before OF
+      old_context_buffer = context_buffer;
+      lookahead_token = get_token(1);
+      if (lookahead_token != OF) {
+	yylval.str = strsave("east");
+	return VARIABLE;
+      }
+      else
+	return t;
+    case WEST:
+      // recognise WEST only before OF
+      old_context_buffer = context_buffer;
+      lookahead_token = get_token(1);
+      if (lookahead_token != OF) {
+	yylval.str = strsave("west");
+	return VARIABLE;
+      }
+      else
+	return t;
+    case TOP:
+      // recognise TOP only before OF
+      old_context_buffer = context_buffer;
+      lookahead_token = get_token(1);
+      if (lookahead_token != OF) {
+	yylval.str = strsave("top");
+	return VARIABLE;
+      }
+      else
+	return t;
+    case BOTTOM:
+      // recognise BOTTOM only before OF
+      old_context_buffer = context_buffer;
+      lookahead_token = get_token(1);
+      if (lookahead_token != OF) {
+	yylval.str = strsave("bottom");
+	return VARIABLE;
+      }
+      else
+	return t;
+    case CENTER:
+      // recognise CENTER only before OF
+      old_context_buffer = context_buffer;
+      lookahead_token = get_token(1);
+      if (lookahead_token != OF) {
+	yylval.str = strsave("center");
+	return VARIABLE;
+      }
+      else
+	return t;
+    case START:
+      // recognise START only before OF
+      old_context_buffer = context_buffer;
+      lookahead_token = get_token(1);
+      if (lookahead_token != OF) {
+	yylval.str = strsave("start");
+	return VARIABLE;
+      }
+      else
+	return t;
+    case END:
+      // recognise END only before OF
+      old_context_buffer = context_buffer;
+      lookahead_token = get_token(1);
+      if (lookahead_token != OF) {
+	yylval.str = strsave("end");
+	return VARIABLE;
+      }
+      else
+	return t;
+    default:
+      return t;
+    }
+  }
+}
+
+void lex_error(const char *message,
+	       const errarg &arg1,
+	       const errarg &arg2,
+	       const errarg &arg3)
+{
+  const char *filename;
+  int lineno;
+  if (!input_stack::get_location(&filename, &lineno))
+    error(message, arg1, arg2, arg3);
+  else
+    error_with_file_and_line(filename, lineno, message, arg1, arg2, arg3);
+}
+
+void lex_warning(const char *message,
+		 const errarg &arg1,
+		 const errarg &arg2,
+		 const errarg &arg3)
+{
+  const char *filename;
+  int lineno;
+  if (!input_stack::get_location(&filename, &lineno))
+    warning(message, arg1, arg2, arg3);
+  else
+    warning_with_file_and_line(filename, lineno, message, arg1, arg2, arg3);
+}
+
+void yyerror(const char *s)
+{
+  const char *filename;
+  int lineno;
+  const char *context = 0;
+  if (lookahead_token == -1) {
+    if (context_buffer.length() > 0) {
+      context_buffer += '\0';
+      context = context_buffer.contents();
+    }
+  }
+  else {
+    if (old_context_buffer.length() > 0) {
+      old_context_buffer += '\0';
+      context = old_context_buffer.contents();
+    }
+  }
+  if (!input_stack::get_location(&filename, &lineno)) {
+    if (context) {
+      if (context[0] == '\n' && context[1] == '\0')
+	error("%1 before newline", s);
+      else
+	error("%1 before '%2'", s, context);
+    }
+    else
+      error("%1 at end of picture", s);
+  }
+  else {
+    if (context) {
+      if (context[0] == '\n' && context[1] == '\0')
+	error_with_file_and_line(filename, lineno, "%1 before newline", s);
+      else
+	error_with_file_and_line(filename, lineno, "%1 before '%2'",
+				 s, context);
+    }
+    else
+      error_with_file_and_line(filename, lineno, "%1 at end of picture", s);
+  }
+}
+