Several enhancements: (1) Added command option "gds no_duplicates"

to allow a "gds read" command to ignore cells in the GDS which already
exist in memory.  This allows magic to be "pre-seeded" with specific
views of cells in the GDS.  Default is false, which is backwards-
compatble behavior.  (2) Changed the behavior of the the way the use
path is written to and read from a .mag file, checking the path prefix
against Tcl variables PDK_PATH, PDKPATH, PDK_ROOT, and PDKROOT, and
replacing any such leading path component with the variable name.
On reading a .mag file, any variable name at the start of the path
that matches a Tcl variable will be substituted.

calma/CalmaRdcl.c

@@ -290,6 +290,7 @@ calmaParseStructure(filename)
     off_t filepos;
     bool was_called;
     bool was_initialized;
+    bool predefined;
     CellDef *def;
 
     /* Make sure this is a structure; if not, let the caller know we're done */
@@ -299,6 +300,7 @@ calmaParseStructure(filename)
 
     /* Read the structure name */
     was_initialized = FALSE;
+    predefined = FALSE;
     if (!calmaSkipExact(CALMA_BGNSTR)) goto syntaxerror;
     if (!calmaReadStringRecord(CALMA_STRNAME, &strname)) goto syntaxerror;
     TxPrintf("Reading \"%s\".\n", strname);
@@ -345,7 +347,12 @@ calmaParseStructure(filename)
 	    freeMagic(newname);
 	}
     }
-    cifReadCellDef = calmaFindCell(strname, &was_called);
+    cifReadCellDef = calmaFindCell(strname, &was_called, &predefined);
+    if (predefined == TRUE)
+    {
+	calmaNextCell();
+	return TRUE;
+    }
     DBCellClearDef(cifReadCellDef);
     DBCellSetAvail(cifReadCellDef);
     HashSetValue(he, cifReadCellDef);
@@ -666,7 +673,7 @@ calmaElementSref(filename)
 	{
 	    TxPrintf("Cell definition %s does not exist!\n", sname);
 	    fseek(calmaInputFile, originalFilePos, SEEK_SET);
-	    def = calmaFindCell(sname, NULL);
+	    def = calmaFindCell(sname, NULL, NULL);
 	    /* Cell flags set to "dereferenced" in case there is no	*/
 	    /* definition in the GDS file.  If there is a definition	*/
 	    /* made after the instance, then the flag will be cleared.	*/
@@ -674,7 +681,7 @@ calmaElementSref(filename)
 	}
     }
 
-    if (!def) def = calmaFindCell(sname, NULL);
+    if (!def) def = calmaFindCell(sname, NULL, NULL);
 
     if (DBIsAncestor(def, cifReadCellDef))
     {
@@ -1031,13 +1038,16 @@ gdsCopyPaintFunc(tile, gdsCopyRec)
  */
 
 CellDef *
-calmaFindCell(name, was_called)
+calmaFindCell(name, was_called, predefined)
     char *name;		/* Name of desired cell */
     bool *was_called;	/* If this cell is in the hash table, then it
 			 * was instanced before it was defined.  We
 			 * need to know this so as to avoid flattening
 			 * the cell if requested.
 			 */
+    bool *predefined;	/* If this cell was in memory before the GDS
+			 * file was read, then this flag gets set.
+			 */
 
 {
     HashEntry *h;
@@ -1059,6 +1069,16 @@ calmaFindCell(name, was_called)
 	     */
 	     DBReComputeBbox(def);
 	}
+	else
+	{
+	    TxPrintf("Warning:  cell %s already existed before reading GDS!\n",
+			name);
+	    if (CalmaNoDuplicates)
+	    {
+		if (predefined) *predefined = TRUE;
+	    	TxPrintf("Using pre-existing cell definition\n");
+	    }
+	}
 	HashSetValue(h, def);
 	if (was_called) *was_called = FALSE;
     }

calma/CalmaRead.c

@@ -77,6 +77,11 @@ bool CalmaPostOrder = FALSE;		/* If TRUE, forces the GDS parser to
 					 * flatten cells that are contact cuts.
 					 * Added by Nishit 8/16/2004
 					 */
+bool CalmaNoDuplicates = FALSE;		/* If TRUE, then if a cell exists in
+					 * memory with the same name as a cell	
+					 * in the GDS file, then the cell in
+					 * the GDS file is skipped.
+					 */
 extern void calmaUnexpected();
 extern int calmaWriteInitFunc();
 

calma/calma.h

@@ -31,6 +31,7 @@ extern bool CalmaDoLabels;
 extern bool CalmaDoLibrary;
 extern bool CalmaDoLower;
 extern bool CalmaAddendum;
+extern bool CalmaNoDuplicates;
 extern bool CalmaMergeTiles;
 extern bool CalmaFlattenArrays;
 extern bool CalmaNoDRCCheck;

commands/CmdCD.c

@@ -99,13 +99,14 @@ bool cmdDumpParseArgs();
 #define	CALMA_LIBRARY	8
 #define	CALMA_LOWER	9
 #define CALMA_MERGE	10
-#define CALMA_READ	11
+#define CALMA_NO_DUP	11
-#define CALMA_READONLY	12
+#define CALMA_READ	12
-#define CALMA_RESCALE	13
+#define CALMA_READONLY	13
-#define CALMA_WARNING	14
+#define CALMA_RESCALE	14
-#define CALMA_WRITE	15
+#define CALMA_WARNING	15
-#define CALMA_POLYS	16
+#define CALMA_WRITE	16
-#define CALMA_PATHS	17
+#define CALMA_POLYS	17
+#define CALMA_PATHS	18
 
 #define CALMA_WARN_HELP CIF_WARN_END	/* undefined by CIF module */
 
@@ -138,6 +139,7 @@ CmdCalma(w, cmd)
 	"library [yes|no]	do not output the top level, only subcells",
 	"lower [yes|no]		allow both upper and lower case in labels",
 	"merge [yes|no]		merge tiles into polygons in the output",
+	"noduplicates [yes|no]	do not read cells that exist before reading GDS",
 	"read file		read Calma GDS-II format from \"file\"\n"
 	"		into edit cell",
 	"readonly [yes|no]	set cell as read-only and generate output from GDS file",
@@ -451,6 +453,26 @@ CmdCalma(w, cmd)
 	    CalmaSubcellPolygons = (option < 3) ? FALSE : TRUE;
 	    return;
 
+	case CALMA_NO_DUP:
+	    if (cmd->tx_argc == 2)
+	    {
+#ifdef MAGIC_WRAPPER
+		Tcl_SetObjResult(magicinterp, Tcl_NewBooleanObj(CalmaNoDuplicates));
+#else
+		TxPrintf("Cell defs that exist before reading GDS will not be paresd.\n",
+			(CalmaNoDuplicates) ?  "not " : "");
+#endif
+		return;
+	    }
+	    else if (cmd->tx_argc != 3)
+		goto wrongNumArgs;
+
+	    option = Lookup(cmd->tx_argv[2], cmdCalmaYesNo);
+	    if (option < 0)
+		goto wrongNumArgs;
+	    CalmaNoDuplicates = (option < 3) ? FALSE : TRUE;
+	    return;
+
 	case CALMA_PATHS:
 	    if (cmd->tx_argc == 3)
 	    {

database/DBio.c

@@ -45,6 +45,7 @@ static char rcsid[] __attribute__ ((unused)) = "$Header: /usr/cvsroot/magic-8.0/
 #include <paths.h>
 #endif
 
+#include "tcltk/tclmagic.h"
 #include "utils/magic.h"
 #include "utils/geometry.h"
 #include "tiles/tile.h"
@@ -1373,7 +1374,7 @@ badTransform:
     else if (DBIsAncestor(subCellDef, cellDef))
     {
 	/*
-	 * Watchout for attempts to create circular structures.
+	 * Watch out for attempts to create circular structures.
 	 * If this happens, disregard the subcell.
 	 */
 	TxPrintf("Subcells are used circularly!\n");
@@ -1382,6 +1383,33 @@ badTransform:
 	goto nextLine;
     }
 
+#ifdef MAGIC_WRAPPER
+    /* If path starts with '$' then check for a possible Tcl variable	*/
+    /* replacement.							*/
+
+    if (*pathptr == '$')
+    {
+	char *varstart, *varend, savechar, *tvar;
+
+	varstart = pathptr + 1;
+	if (*varstart == '{') varstart++;
+	varend = varstart + 1;
+	while (*varend != '\0' && *varend != '}' && *varend != '/'
+			&& *varend != '\n' && *varend != ' ') varend++;
+	savechar = *varend;
+	*varend = '\0';
+
+	tvar = (char *)Tcl_GetVar(magicinterp, varstart, TCL_GLOBAL_ONLY);
+	*varend = savechar;
+	if (savechar == '}') varend++;
+	if (tvar)
+	{
+	    memmove(pathptr + strlen(tvar), varend, strlen(varend) + 1);
+	    memmove(pathptr, tvar, strlen(tvar));
+	}
+    }
+#endif
+
     /* Relative path handling:  If path does not have a leading "/"	*/
     /* or "~" and cellDef->cd_file has path components, then the path	*/
     /* should be interpreted relative to the path of the parent cell.	*/
@@ -3146,6 +3174,7 @@ dbWriteCellFunc(cellUse, cdarg)
     struct writeArg *arg = (struct writeArg *) cdarg;
     Transform *t;
     Rect *b;
+    bool subbed = FALSE;
     char     cstring[256], *pathend, *pathstart, *parent;
 
     t = &(cellUse->cu_transform);
@@ -3196,6 +3225,70 @@ dbWriteCellFunc(cellUse, cdarg)
 		cellUse->cu_id);
     }
     else
+    {
+#ifdef MAGIC_WRAPPER
+	char *tvar;
+
+	/* Check for the leading component of the file path being equal to	*/
+	/* one of several common variable names for the PDK location, and	*/
+	/* if there is a match, then substitute the variable name for the	*/
+	/* matching leading path component.					*/
+
+	if (subbed == FALSE)
+	{
+	    tvar = (char *)Tcl_GetVar(magicinterp, "PDK_PATH", TCL_GLOBAL_ONLY);
+	    if (tvar)
+		if (!strncmp(pathstart, tvar, strlen(tvar)))
+		{
+	    	    sprintf(cstring, "use %s %c%s $PDK_PATH%s\n",
+				cellUse->cu_def->cd_name,
+				(cellUse->cu_flags & CU_LOCKED) ? CULOCKCHAR : ' ',
+				cellUse->cu_id, pathstart + strlen(tvar));
+		    subbed = TRUE;
+		}
+	}
+	if (subbed == FALSE)
+	{
+	    tvar = (char *)Tcl_GetVar(magicinterp, "PDKPATH", TCL_GLOBAL_ONLY);
+	    if (tvar)
+		if (!strncmp(pathstart, tvar, strlen(tvar)))
+		{
+	    	    sprintf(cstring, "use %s %c%s $PDKPATH%s\n",
+				cellUse->cu_def->cd_name,
+				(cellUse->cu_flags & CU_LOCKED) ? CULOCKCHAR : ' ',
+				cellUse->cu_id, pathstart + strlen(tvar));
+		    subbed = TRUE;
+		}
+	}
+	if (subbed == FALSE)
+	{
+	    tvar = (char *)Tcl_GetVar(magicinterp, "PDK_ROOT", TCL_GLOBAL_ONLY);
+	    if (tvar)
+		if (!strncmp(pathstart, tvar, strlen(tvar)))
+		{
+	    	    sprintf(cstring, "use %s %c%s $PDK_ROOT%s\n",
+				cellUse->cu_def->cd_name,
+				(cellUse->cu_flags & CU_LOCKED) ? CULOCKCHAR : ' ',
+				cellUse->cu_id, pathstart + strlen(tvar));
+		    subbed = TRUE;
+		}
+	}
+	if (subbed == FALSE)
+	{
+	    tvar = (char *)Tcl_GetVar(magicinterp, "PDKROOT", TCL_GLOBAL_ONLY);
+	    if (tvar)
+		if (!strncmp(pathstart, tvar, strlen(tvar)))
+		{
+	    	    sprintf(cstring, "use %s %c%s $PDKROOT%s\n",
+				cellUse->cu_def->cd_name,
+				(cellUse->cu_flags & CU_LOCKED) ? CULOCKCHAR : ' ',
+				cellUse->cu_id, pathstart + strlen(tvar));
+		    subbed = TRUE;
+		}
+	}
+#endif
+
+	if (subbed == FALSE)
 	{
 	    /* If path starts with home path, then replace with "~"	*/
 	    /* to make IP semi-portable between home directories	*/
@@ -3218,6 +3311,7 @@ dbWriteCellFunc(cellUse, cdarg)
 			cellUse->cu_id, pathstart);
 	    }
 	}
+    }
     FPRINTR(arg->wa_file, cstring);
 
     cellUse->cu_def->cd_flags |= CDVISITED;