/*
  Copyright 2003,2009 Ronald S. Burkey <info@sandroid.org>
  
  This file is part of yaAGC.

  yaAGC 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 of the License, or
  (at your option) any later version.

  yaAGC 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 yaAGC; if not, write to the Free Software
  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

  Filename:	SymbolTable.c
  Purpose:	Stuff for managing the assembler's symbol table.
  Mode:		04/11/03 RSB.	Began.
  		04/17/03 RSB.	Removed Namespaces.
		07/27/05 JMS    Added support for writing the symbol 
				table to a file for symbol debugging 
				purposes.
		07/28/05 JMS    Added support for writing SymbolLines
				to symbol table file.
		08/03/05 JMS    Support for yaLEMAP
		03/20/09 RSB	Corrected symbol tables (as written
				to files) to always use little-endian
				representations of integers.  This
				isn't important for someone compiling
				their own AGC code, but is needed for
				moving symbol tables from one CPU type
				to another, such as for distributing
				Virtual AGC binaries to PowerPC vs.
				Intel CPUs. Also, in the on-disk symbol
				table we now pad filenames with 0
				to make automated regression testing of
				the symtabs easier.
		06/28/09 RSB	Added HTML output.
		06/29/09 RSB	Added a little css to prevent wrapping
				in the HTML output.
		06/27/09 RSB	(Later.)  Used more css to get rid of
				the underlining for links, and to change
				the color of a visited link from purple
				to a dimmer bluish color.
		06/30/09 RSB	Added HtmlCheck for processing 
				"<HTML>...</HTML>" stuff in source files.
				Includes <HTMLn> and <HTML=f>.
		07/01/09 RSB	Altered the way the highlighting styles
				(COLOR_XXX) work in order to make them
				more flexible and to shorten up the HTML
				files more.  Added "##" HTML-insert 
				syntax, default style, etc.

  Concerning the concept of a symbol's namespace.  I had originally 
  intended to implement this, and so many functions had a namespace
  parameter.  I've decided to remove the parameters, but there is 
  still the underlying code for it, in case it might be handy in the
  future.
*/

#include "yaYUL.h"
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <unistd.h>
#include <fcntl.h>

//-------------------------------------------------------------------------
// Some global data.

// On the first pass, the symbols are collected into an unsorted array.  
// At the end of the pass the array is sorted, and duplicates will cause 
// error messages.  The symbol table is initially empty.  Whenever more 
// symbols are defined than the table has room for, its space is enlarged.  
// On the second pass, true values are assigned to the symbols.
Symbol_t *SymbolTable = NULL;
int SymbolTableSize = 0, SymbolTableMax = 0;

//-------------------------------------------------------------------------
// Here are functions for converting integers in-place between the CPU native
// representation and little-endian format.  These functions are symmetric,
// in the sense that they convert in either direction.  The functions do
// not check in any way that the data being pointed to is 32-bit.  The 
// case of an Address_t datatype as input is particularly interesting.
// This datatype has 32-bit fields, and they must each be converted by a
// separate call to LittleEndian32.  However, the datatype *begins* with a 
// bunch of packed bitfields, so calling LittleEndian32 on an Address_t will
// attempt to rearrange the packing of those bitfields.  Whether that's 
// correct and perfectly portable thing to do, I'm not sure.

#if __BYTE_ORDER != __LITTLE_ENDIAN

static 
void SwapBytes (void *Pointer, int Loc1, int Loc2)
{
  char c, *s1, *s2;
  s1 = ((char *) Pointer) + Loc1;
  s2 = ((char *) Pointer) + Loc2;
  c = *s1;
  *s1 = *s2;
  *s2 = c;
}

#endif

#if __BYTE_ORDER == __LITTLE_ENDIAN

void
LittleEndian32 (void *Value)
{
}

#elif __BYTE_ORDER == __BIG_ENDIAN

void
LittleEndian32 (void *Value)
{
  SwapBytes (Value, 0, 3);
  SwapBytes (Value, 1, 2);
}

#elif __BYTE_ORDER == __PDP_ENDIAN

void
LittleEndian32 (void *Value)
{
  SwapBytes (Value, 0, 2);
  SwapBytes (Value, 1, 3);
}

#else

#error Sorry, not a supported endian type.

#endif

//-------------------------------------------------------------------------
// Normalize an assembly-language filename by turning ".s" into ".html" if
// possible, but otherwise simply appending ".html".
char *
NormalizeFilename (char *SourceName)
{
  static char HtmlFilename[1025];
  int n;
  strcpy (HtmlFilename, SourceName);
  n = strlen (HtmlFilename);
  if (!strcmp (&HtmlFilename[n - 2], ".s"))
    n -= 2;
  strcpy (&HtmlFilename[n], ".html");
  return (HtmlFilename);
}

//-------------------------------------------------------------------------
// Create an HTML output file.  Return 0 on success, 1 on failure.  
int
HtmlCreate (char *Filename)
{
  char *HtmlFilename;
  HtmlFilename = NormalizeFilename (Filename);
  HtmlOut = fopen (HtmlFilename, "w");
  if (HtmlOut == NULL)
    {
      printf ("Cannot create HTML file \"%s\"\n", HtmlFilename);
      return (1);
    }
  // Write the HTML header.
  fprintf (HtmlOut, "%s",
	   "<!DOCTYPE html PUBLIC \"-//W3C//DTD HTML 4.01 Transitional//EN\">\n"
	   "<html>\n"
	   "<head>\n"
	   "<meta content=\"text/html;charset=ISO-8859-1\" http-equiv=\"Content-Type\">\n"
	   "<title>Assembly listing generated by yaYUL</title>\n"
	   
	   "<style type=\"text/css\">\n"
	   "p.nobreak { white-space:nowrap; }\n"
	   "a { text-decoration:none; }\n"
	   "a:visited { COLOR: #000850; }\n"
	   "</style>\n"
	   
	   "<style type=\"text/css\">\n"
	   ".op{\n"
	   "font-weight: bold;\n"
	   "color: #993300;\n"
	   "}\n"
	   "</style>\n"
	   
	   "<style type=\"text/css\">\n"
	   ".dn{\n"
	   "color: #009900;\n"
	   "}\n"
	   "</style>\n"
	   
	   "<style type=\"text/css\">\n"
	   ".fe{\n"
	   "color: #FF0000;\n"
	   "}\n"
	   "</style>\n"
	   
	   "<style type=\"text/css\">\n"
	   ".in{\n"
	   "color: #FF6600;\n"
	   "}\n"
	   "</style>\n"
	   
	   "<style type=\"text/css\">\n"
	   ".ps{\n"
	   "color: #336600;\n"
	   "}\n"
	   "</style>\n"
	   
	   "<style type=\"text/css\">\n"
	   ".sm{\n"
	   "color: #0000FF;\n"
	   "}\n"
	   "</style>\n"
	   
	   "<style type=\"text/css\">\n"
	   ".wn{\n"
	   "color: #FF9900;\n"
	   "}\n"
	   "</style>\n"
	   
	   "<style type=\"text/css\">\n"
	   ".co{\n"
	   "font-style: italic;\n"
	   "color: #993399;\n"
	   "}\n"
	   "</style>\n"
	   
	   "</head>\n"
	   "<body>\n"
	   HTML_STYLE_START
	   "<h1>Source Code</h1>\n");
  return (0);
}

//-------------------------------------------------------------------------
// Close out the HTML file that is open for output.
void
HtmlClose (void)
{
  if (HtmlOut == NULL)
    return;
  fprintf (HtmlOut, "%s", HTML_STYLE_END "</body>\n</html>\n");
  fclose (HtmlOut);
}

//-------------------------------------------------------------------------
// For processing HTML insertion --- i.e., putting HTML-related stuff into
// the source files so that it can be eventually stuck into the HTML-
// formatted assembly listing.  There are two basic variations: the "<HTML>"
// style and the "##" style.  There is also a default style file which can
// be used (at assembly-time).

static int StyleInitialized = 0;
int StyleOnly = 0;

int
HtmlCheck (int WriteOutput, FILE *InputFile, char *s, int sSize,  
	   char *CurrentFilename, int *CurrentLineAll, int *CurrentLineInFile)
{
  static int StyleBox = 0, StyleBoxWidth = 75, StyleUser = 0;
  static char StyleUserStart[2049] = "", StyleUserEnd[1025] = "";
  int Width, Pos = 0;
  int i, j;
  char c = 0, *ss;
  
  // Process default style file at startup.
  if (!StyleInitialized)
    {
      FILE *Defaults;
      StyleInitialized = 1;
      Defaults = fopen ("Default.style", "r");
      if (Defaults != NULL)
        {
	  Line_t s = { 0 };
	  StyleOnly = 1;
	  while (NULL != fgets (s, sizeof (s) - 1, Defaults))
	    HtmlCheck (0, Defaults, s, sizeof (s), "", &i, &j);
	  StyleOnly = 0;
          fclose (Defaults);
	}
    }
  
  if (StyleOnly)
    goto ProcessStyle;
Retry:  
  Pos = 0;
  c = 0;
  
  // First, take care of directives to include HTML from a 
  // file.  There are two forms:
  //	<HTML "filename">
  // or
  //	### FILE="filename"
  if (!strncmp (s, "<HTML \"", 7))
    Pos = 7;
  else if (!strncmp (s, "### FILE=\"", 10))
    Pos = 10;
  if (Pos)
    {
      FILE *Include;
      if (!WriteOutput || !Html || HtmlOut == NULL)
        return (1);
      for (ss = &s[Pos]; *ss && *ss != '\"'; ss++);
      if (*ss != '\"')
        return (1);
      *ss = 0;
      Include = fopen (&s[Pos], "r");
      *ss = '\"';
      if (Include == NULL)
        return (1);
      fprintf (HtmlOut, "%s", HTML_STYLE_END);
      while (NULL != fgets (s, sSize - 1, Include))
        fprintf (HtmlOut, "%s", s);
      fprintf (HtmlOut, "%s", HTML_STYLE_START);
      fclose (Include);
      return (1);
    }
    
  // Take care of the addition of destinations for hyperlinks.
  if (!strncmp (s, "### ANCHOR=", 11))
    {
      if (!WriteOutput || !Html || HtmlOut == NULL)
        return (1);
      for (ss = s; *ss && *ss != '\n'; ss++);
      *ss = 0;
      fprintf (HtmlOut, "<a name=\"%s\">\n", &s[11]);
      return (1);
    }
    
  // Now take care of style pragmas.  The allowed forms are
  //	### STYLE=NONE
  // or
  //	### STYLE=BOX n%
  // or
  //	### STYLE=START stuff
  //	### STYLE=START+ stuff
  //	### STYLE=END stuff
  // or
  //	### STYLE=USER
  // The latter just re-enables STYLE=START/STYLE=END styles which
  // may have been defined earlier but then disabled temporarily
  // with STYLE=NONE or STYLE=BOX.  STYLE=START/STYLE=START+/STYLE=END 
  // is a user-defined style, in which you can give
  // both the HTML to initiate the style and the HTML to end 
  // the style to allow returning to the default style.  In other
  // words, when a block of comments in "## htmlstuff" format
  // is encountered, the style-start stuff will be output,
  // followed by all of the htmlstuff in the ## comments, followed
  // by the style-end stuff.  STYLE=START gives the starting commands,
  // but since such commands are sometimes gargantuan, they may not
  // fit conveniently on a single line, so what STYLE=START+ does is
  // to *add* stuff to the end of a previous STYLE=START or 
  // STYLE=START+.
  if (!strncmp (s, "### STYLE=", 10))
    {
      if (!WriteOutput || !Html || HtmlOut == NULL)
        return (1);
    ProcessStyle:
      ss = &s[10];
      if (!strncmp (ss, "NONE", 4))
        {
	  StyleBox = 0;
	  StyleUser = 0;
	}
      else if (!strncmp (ss, "BOX ", 4) && 
      	       2 == sscanf (ss + 4, "%d%c", &i, &c) &&
	       i >= 1 && i <= 100 &&
	       c == '%')
        {
	  StyleBox = 1;
	  StyleBoxWidth = i;
	  StyleUser = 0;
	}
      else if (!strncmp (ss, "USER", 4))
        {
	  StyleBox = 0;
	  StyleUser = 1;
	}
      else if (!strncmp (ss, "START ", 6))
        {
	  StyleBox = 0;
	  StyleUser = 1;
	  strcpy (StyleUserStart, &ss[6]);
	}
      else if (!strncmp (ss, "START+ ", 7))
        {
	  strcat (StyleUserStart, &ss[7]);
	}
      else if (!strncmp (ss, "END ", 4))
        {
	  StyleBox = 0;
	  StyleUser = 1;
	  strcpy (StyleUserEnd, &ss[4]);
	}
	
      return (1);
    }  
    
  // Now take care of HTML embedded with
  //	## stuff
  if (!strncmp (s, "## ", 3))
    {
      // Set proper style and output the line.
      if (WriteOutput && Html && HtmlOut != NULL)
        {
	  fprintf (HtmlOut, "%s", HTML_STYLE_END);
	  if (StyleBox)
	    fprintf (HtmlOut, HTML_TABLE_START, StyleBoxWidth);
	  else if (StyleUser)
	    fprintf (HtmlOut, "%s", StyleUserStart);
	  fprintf (HtmlOut, "%s", &s[3]);
	}
      // Loop on the lines of the insert.
      while (1)
	{
	  ss = fgets (s, sSize - 1, InputFile);
	  if (ss == NULL)
	    break;
	  (*CurrentLineAll)++;
	  (*CurrentLineInFile)++;  
	  if (strncmp (s, "## ", 3))
	    break;
	  if (WriteOutput && Html && HtmlOut != NULL)
	    fprintf (HtmlOut, "%s", &s[3]);
	}
      // Restore default style.
      if (WriteOutput && Html && HtmlOut != NULL)
	{
	  if (StyleBox)
	    fprintf (HtmlOut, "%s", HTML_TABLE_END);
	  else if (StyleUser)
	    fprintf (HtmlOut, "%s", StyleUserEnd);
	  fprintf (HtmlOut, "%s", HTML_STYLE_START);
	}
      if (ss == NULL)
        return (1);
      goto Retry;
    }
    
  // Now take care of the <HTML> or <HTMLnn> tags.  However,
  // the ## style described above is preferred.
  if (!strncmp (s, "<HTML>", 6) || 
      (2 == sscanf (s, "<HTML%d%c", &Width, &c) && 
       Width > 0 && Width <= 99 && c == '>'))
    {
      // Turn off default HTML styling.
      if (WriteOutput && Html && HtmlOut != NULL)
        {
	  fprintf (HtmlOut, "%s", HTML_STYLE_END);
	  if (c == '>')
	    fprintf (HtmlOut, HTML_TABLE_START, Width);
	}
      // Loop on the lines of the insert.
      while (1)
	{
	  ss = fgets (s, sSize - 1, InputFile);
	  if (ss == NULL)
	    {
	      printf ("Premature end-of-file.\n");
	      fprintf (stderr, "%s:%d: Premature end-of-file.\n",
		       CurrentFilename, *CurrentLineInFile);
	      goto Done;
	    }
	  (*CurrentLineAll)++;
	  (*CurrentLineInFile)++;  
	  if (!strncmp (s, "</HTML>", 7))
	    {
	    Done:
	      // Turn default HTML styling back on and return
	      // to normal source processing.
	      if (WriteOutput && Html && HtmlOut != NULL)
	        {
		  if (c == '>')
		    fprintf (HtmlOut, "%s", HTML_TABLE_END);
		  fprintf (HtmlOut, "%s", HTML_STYLE_START);
		}
	      break;
	    }
	  if (WriteOutput && Html && HtmlOut != NULL)
	    fprintf (HtmlOut, "%s", s);
	}
      return (1);
    }
  return (0);
}
      
//-------------------------------------------------------------------------
// Normalize a variable, constant name, or line label to a form that can be
// used as an html anchor point.  Since we know that all such names are 
// 8 characters or less, we can simply convert the ASCII characters to 
// 2-digit hexadecimal and end up with 16-character labels or less.  For
// example, "ABCD" -> "41424344".
char *
NormalizeAnchor (char *Name)
{
  static char Normalized[17], *EndPoint = &Normalized[sizeof (Normalized) - 1];
  char *s;
  for (s = Normalized, *s = 0; *Name != 0 && s < EndPoint; s += 2, Name++)
    sprintf (s, "%02X", *Name);
  return (Normalized);
}

//-------------------------------------------------------------------------
// Normalize a string by fixing up the '<' and '&' characters, so that they
// can't have bogus html tags in them.  It handles tabs also, but they can
// only be interpreted relative to the beginning of the input string rather
// than to page position.  If the number of print positions is less than
// PadTo, pad with spaces until it is the right length.
char *
NormalizeStringN (char *Input, int PadTo)
{
  static char Output[2000], *EndPoint = &Output[sizeof (Output) - 1 - 6];
  char *s, *Start;
  int Pos = 0;
  Start = Input;
  for (s = Output, *s = 0; *Input != 0 && s < EndPoint; Input++)
    {
      if (*Input == '<')
        {
	  strcpy (s, "&lt;");
	  s += 4;
	  Pos++;
	}
      else if (*Input == '&')
        {
	  strcpy (s, "&amp;");
	  s += 5;
	  Pos++;
	}
      else if (*Input == '\t')
        {
	  int i;
	  i = ((Pos + 8) & ~7) - Pos; 
	  Pos += i;
	  for (; i > 0; i--)
	    {
	      strcpy (s, " ");
	      s += 1;
	    }
	  
	}
      else 
        {
          *s++ = *Input;
	  Pos++;
	}
    }
  for (; Pos < PadTo; Pos++)
    {
      strcpy (s, " ");
      s += 1;
    }
  *s = 0;
  return (Output);
}

char *
NormalizeString (char *Input)
{
  return (NormalizeStringN (Input, 0));
}

//-------------------------------------------------------------------------
// Delete the symbol table.

void
ClearSymbols (void)
{
  if (SymbolTable != NULL)
    free (SymbolTable);
  SymbolTable = NULL;
  SymbolTableSize = SymbolTableMax = 0;  
}

//-------------------------------------------------------------------------
// Add a symbol to the table.  The newly-added symbol always has the value
// ILLEGAL_SYMBOL_VALUE.  Returns 0 on success, or non-zero on fatal
// error.

int
AddSymbol (const char *Name)
{
  char Namespace = 0;
  
  // A sanity clause.
  if (strlen (Name) > MAX_LABEL_LENGTH)
    {
      printf ("Symbol name \"%s\" is too long.\n", Name);
      return (1);
    }
  // If the symbol table is too small, enlarge it.
  if (SymbolTableSize == SymbolTableMax)
    {
      if (SymbolTable==NULL)
        {
	  // This default size comes from the fact that I know there are about
	  // 7100 symbols in the Luminary131 symbol table. There are far fewer
	  // symbols in yaLEMAP, but that is ok since this isn't much memory
	  // anyhow.
	  SymbolTableMax = 10000;
          SymbolTable = (Symbol_t *) calloc (SymbolTableMax, sizeof (Symbol_t));
	}
      else
        {
          SymbolTableMax += 1000;
	  SymbolTable = (Symbol_t *) realloc (SymbolTable, 
					      SymbolTableMax * sizeof (Symbol_t));
	}
      if (SymbolTable == NULL)
        {
	  printf ("Out of memory (3).\n");
	  return (1);
	}
    }
  // Now add the symbol.
  SymbolTable[SymbolTableSize].Namespace = Namespace;
  SymbolTable[SymbolTableSize].Value.Invalid = 1;
  strcpy (SymbolTable[SymbolTableSize].Name, Name);
  SymbolTableSize++;
  return (0); 
}

//-------------------------------------------------------------------------
// JMS: Assign a symbol a new value. Returns 0 on success. This is used for
// backward compatability to avoid changing lots of existing code. Sets the
// new debugging parameters to their default values.
int
EditSymbol (const char *Name, Address_t *Value)
{
  return EditSymbolNew (Name, Value, SYMBOL_REGISTER, "", 0);
}

//-------------------------------------------------------------------------
// Compare two symbol-table entries, for comparison purposes.  Both the
// Namespace and Name fields are used.

static
int CompareSymbolName (const void *Raw1, const void *Raw2)
{
#define Element1 ((Symbol_t *) Raw1)
#define Element2 ((Symbol_t *) Raw2)
  if (Element1->Namespace < Element2->Namespace)
    return (-1);
  if (Element1->Namespace > Element2->Namespace)
    return (1);
  return (strcmp (Element1->Name, Element2->Name));    
#undef Element1
#undef Element2
}

//-------------------------------------------------------------------------
// Sort the symbol table.  Returns the number of duplicated symbols.

int
SortSymbols (void)
{
  int i, j, ErrorCount = 0;
  qsort (SymbolTable, SymbolTableSize, sizeof (Symbol_t), CompareSymbolName);
  // If a symbol is duplicated (in the same namespace), be remove the
  // duplicates.
  for (i = 1; i < SymbolTableSize; )
    {
      if (SymbolTable[i - 1].Namespace == SymbolTable[i].Namespace &&
          !strcmp (SymbolTable[i - 1].Name, SymbolTable[i].Name))
        {
	  printf ("Symbol \"%s\" (%d) is duplicated.\n", 
	          SymbolTable[i].Name, SymbolTable[i].Namespace);
          ErrorCount++;		  
	  for (j = i; j < SymbolTableSize; j++)
	    SymbolTable[j - 1] = SymbolTable[j];
	  SymbolTableSize--;  
	}	  
      else
        i++;	
    }
  return (ErrorCount);
}

//-------------------------------------------------------------------------
// Locate a string in the symbol table.  
// Returns a pointer to the symbol-table entry, or NULL if not found.. 

Symbol_t *
GetSymbol (const char *Name)
{
  char Namespace = 0;
  Symbol_t Symbol;
  if (strlen (Name) > MAX_LABEL_LENGTH)
    return (NULL);
  Symbol.Namespace = Namespace;
  strcpy (Symbol.Name, Name);
  return ((Symbol_t *) bsearch (&Symbol, SymbolTable, SymbolTableSize,
                                sizeof (Symbol_t), CompareSymbolName));
}

//------------------------------------------------------------------------
// Print the symbol table.

void
PrintSymbolsToFile (FILE *fp)
{
  int i;
  fprintf (fp, "Symbol Table\n"
          "------------\n");
  if (HtmlOut != NULL)
    fprintf (HtmlOut, "</pre>\n\n<h1>SymbolTable</h1>\n<pre>\n");
  for (i = 0; i < SymbolTableSize; i++)
    {
      if (!(i & 3) && i != 0)
        {
          fprintf (fp, "\n");
	  if (HtmlOut != NULL)
	    fprintf (HtmlOut, "\n");
	}
      fprintf (fp, "%6d:   %-*s   ", i + 1, MAX_LABEL_LENGTH, SymbolTable[i].Name);
      if (HtmlOut)
        {
	  static char s[257];
          sprintf (s, "%06d:   %-*s   ", i + 1, MAX_LABEL_LENGTH, SymbolTable[i].Name);
	  fprintf (HtmlOut, "%s", NormalizeString (s));
	}
      AddressPrint (&SymbolTable[i].Value);
      if (3 != (i & 3))
        {
          fprintf (fp, "\t\t");
	  if (HtmlOut != NULL)
	    fprintf (HtmlOut, NormalizeString ("\t"));
	}
    }
  fprintf (fp, "\n");  
  if (HtmlOut != NULL)
    fprintf (HtmlOut, "\n");
  
}

void
PrintSymbols (void)
{
  PrintSymbolsToFile (stdout);
}

//------------------------------------------------------------------------
// Counts the number of unresolved symbols.

int
UnresolvedSymbols (void)
{
  int i, Ret = 0;
  for (i = 0; i < SymbolTableSize; i++)
    if (SymbolTable[i].Value.Invalid)
      Ret++;
  return (Ret);    
}

//------------------------------------------------------------------------
// JMS: Begin additions for output of symbol table to a file for symbolic
// debugging purposes.
//------------------------------------------------------------------------

// JMS: 07.28

// These holds entries for every single compiled line in the source and
// its file and line number. This table is needed to print out the source
// line as we step through code. It is also needed for "break <line #>".
SymbolLine_t *LineTable = NULL;
int LineTableSize = 0, LineTableMax = 0;

//------------------------------------------------------------------------
// Assign a symbol a new value including is type, and the file name/line
// number from which it came which is used for debugging purposes. Returns
// 0 upon success, 1 upon failure.
int
EditSymbolNew (const char *Name, Address_t *Value, int Type, char *FileName,
	       unsigned int LineNumber)
{
  char Namespace = 0;
  Symbol_t *Symbol;

  // Find out where the symbol is located in the symbol table.
  Symbol = GetSymbol (Name);
  if (Symbol == NULL)
    {
      printf ("Implementation error: symbol %d,\"%s\" lost between passes.\n",
              Namespace, Name);
      return (1);
    }
  // This can't happen, but still ...
  if (strcmp (Name, Symbol->Name))
    {
      printf ("***** Name mismatch:  %s/%s\n", Name, Symbol->Name);
    }  

  // Check to see if the symbol is in a namespace that allows it to be
  // reassigned.
  if (0)
    {
      printf ("Symbol \"%s\" in namespace %d cannot be reassigned.\n",
              Symbol->Name, Symbol->Namespace);
    }

  // Reassign the value.
  Symbol->Value = *Value;

  // Assign the symbol type, file name, and line number
  Symbol->Type = Type;
  Symbol->LineNumber = LineNumber;
  strcpy(Symbol->FileName, FileName);

  return (0);
}

//------------------------------------------------------------------------
// Writes the symbol table to a file in binary format. See yaYUL.h for
// more information about the format. Takes the name of the symbol file.

#ifndef O_BINARY
// The O_BINARY flag is needed only in Windows.  If it's not defined,
// it's okay to just make it zero, because it means it's not needed.
#define O_BINARY 0
#endif

void
WriteSymbolsToFile (char *fname)
{
  int i, fd;
  SymbolFile_t symfile = { { 0 } };
  Symbol_t symbol;
  SymbolLine_t Line;

  // Open the symbol table file
  if ((fd = open (fname, O_BINARY | O_WRONLY | O_CREAT | O_TRUNC, 0666)) < 0) {
    printf ("\nFailed to open symbol table file: %s\n", fname);
    return;
  }

  // Write the SymbolFile_t header to the symbol file, filling its
  // members first.
  getcwd (symfile.SourcePath, MAX_PATH_LENGTH);
  symfile.NumberSymbols = SymbolTableSize;
  symfile.NumberLines = LineTableSize; // JMS: 07.28
  LittleEndian32 (&symfile.NumberSymbols);
  LittleEndian32 (&symfile.NumberLines);
  write (fd, (void *)&symfile, sizeof(SymbolFile_t));

  // Loop and write the symbols to a file
  for (i = 0; i < SymbolTableSize; i++)
    {
      memcpy (&symbol, (void *)&SymbolTable[i], sizeof (Symbol_t));
      LittleEndian32 (&symbol);
      LittleEndian32 (&symbol.Value.Value);
      LittleEndian32 (&symbol.Type);
      LittleEndian32 (&symbol.LineNumber);
      write (fd, (void *) &symbol, sizeof (Symbol_t));
    }

  // JMS: 07.28
  // Loop and write the symbol lines to a file
  for (i = 0; i < LineTableSize; i++)
    {
      memcpy (&Line, (void *)&LineTable[i], sizeof (SymbolLine_t));
      LittleEndian32 (&Line);
      LittleEndian32 (&Line.CodeAddress.Value);
      LittleEndian32 (&Line.LineNumber);
      write (fd, (void *) &Line, sizeof (SymbolLine_t));
    }
  close (fd);
}

//-------------------------------------------------------------------------
// Delete the line table.
void
ClearLines (void)
{
  if (LineTable != NULL)
    free (LineTable);
  LineTable = NULL;
  LineTableSize = LineTableMax = 0;  
}

//-------------------------------------------------------------------------
// Adds a new program line to the table. Takes the Address_t at which this
// is stored in (fixed) memory, and the file name and line number where it
// is found. Takes the number of words the instruction takes up in memory.
// Returns 0 on success, or non-zero on fatal error.
int
AddLine (Address_t *Address, const char *FileName, int LineNumber)
{
  // A sanity clause.
  if (strlen (FileName) > MAX_FILE_LENGTH)
    {
      printf ("File name \"%s\" is too long.\n", FileName);
      return (1);
    }

  // If the line table is too small, enlarge it.
  if (LineTableSize == LineTableMax)
    {
      if (LineTable==NULL)
        {
	  // This default size comes from the fact that I know there is 32K
	  // of fixed memory in the AGC.
	  LineTableMax = 32768;
          LineTable = (SymbolLine_t *) calloc (LineTableMax, sizeof (SymbolLine_t));
	}
      else
        {
          LineTableMax += 1000;
	  LineTable = (SymbolLine_t *) realloc (LineTable, 
						LineTableMax * sizeof (SymbolLine_t));
	}
      if (LineTable == NULL)
        {
	  printf ("Out of memory (3).\n");
	  return (1);
	}
    }

  // Now add the line but adjust for the word inside the instruction.
  LineTable[LineTableSize].CodeAddress = *Address;
  strcpy(LineTable[LineTableSize].FileName, FileName);
  LineTable[LineTableSize].LineNumber = LineNumber;
  LineTableSize++;
  return (0); 
}

//-------------------------------------------------------------------------
// Compare function for the line table. We must sort the lines in increasing
// order of physical address. This routine is used for the AGC way of
// addressing memory.
static int
CompareLineAGC (const void *Raw1, const void *Raw2)
{
#define Address1 ((SymbolLine_t *) Raw1)->CodeAddress
#define Address2 ((SymbolLine_t *) Raw2)->CodeAddress

  // It is unclear whether we can ever get erasable addresses here, I
  // don't think so, so we'll just pretend there are fixed address
  // only. The ordering is by 'bank' then 'address', so fixed banks
  // 00 and 01 come before the unbanked 02 and 03 addresses.
  int Bank1, Bank2;

  if (Address1.Banked && Address1.FB >= 020 && Address1.Super)
    Bank1 = Address1.FB + 010;
  else if (Address1.Banked)
    Bank1 = Address1.FB;
  else
    Bank1 = Address1.SReg / 02000;

  if (Address2.Banked && Address2.FB >= 020 && Address2.Super)
    Bank2 = Address2.FB + 010;
  else if (Address2.Banked)
    Bank2 = Address2.FB;
  else
    Bank2 = Address2.SReg / 02000;

  if (Bank1 < Bank2)
    return -1;
  else if (Bank1 > Bank2)
    return 1;
  else if (Address1.SReg < Address2.SReg)
    return -1;
  else if (Address1.SReg > Address2.SReg)
    return 1;
  else
    return 0;

#undef Address1
#undef Address2
}

//-------------------------------------------------------------------------
// Compare function for the line table. We must sort the lines in increasing
// order of physical address. This uses the yaLEMAP way of addressing.
static int
CompareLineAGS (const void *Raw1, const void *Raw2)
{
#define Address1 ((SymbolLine_t *) Raw1)->CodeAddress
#define Address2 ((SymbolLine_t *) Raw2)->CodeAddress

  if (Address1.SReg < Address2.SReg)
    return -1;
  else if (Address1.SReg > Address2.SReg)
    return 1;
  else
    return 0;

#undef Address1
#undef Address2
}

//-------------------------------------------------------------------------
// Sort the line table.
void
SortLines (int Type)
{
  int i, j;
  int (*Compare)(const void *, const void *);

  // Sort the entries based upon the architecture
  if (Type == SORT_YUL)
    Compare = CompareLineAGC;
  else if (Type == SORT_LEMAP)
    Compare = CompareLineAGS;
  else
    {
      printf ("Invalid architecture type given.\n");
      return;
    }

  qsort (LineTable, LineTableSize, sizeof (SymbolLine_t), Compare);

  // Remove duplicates from the line table. I think this is a completely
  // normal situation because multiple passes are made throug the code
  // when compiling.
  printf("Removing the duplicated lines... ");
  for (i = 1; i < LineTableSize; )
    {
      if (!Compare((const void *)&LineTable[i - 1].CodeAddress,
		   (const void *)&LineTable[i].CodeAddress))
	{
	  AddressPrint(&LineTable[i - 1].CodeAddress);

	  for (j = i; j < LineTableSize; j++)
	    LineTable[j - 1] = LineTable[j];
	  LineTableSize--;  
	}	  
      else
        i++;	
    }
  printf("\n");
}

//------------------------------------------------------------------------
// JMS: End additions for output of symbol table
//------------------------------------------------------------------------
