CodeQL File{MayNot,Never}BeClosed.ql file-handle resource leaks

Guided by CodeQL static code analyser.

FileMayNotBeClosed.ql
FileMayNeverBeClosed.ql

The trick with "if(fp != stdout)" is problematic (to analyser) as
technically 'stdout' can be a global pointer that COULD be modified any
time, so it might have changed between the fopen() and fclose() calls so
the close MAY NEVER occurs (which is problem the analyzer can see).

So local state is maintained as a bool which will also clarify to the
compiler see the intention without concern for external stdout
modification.

Some items appear to be out and out leaks when certain commands are use.

commands/CmdCD.c

@@ -3994,7 +3994,6 @@ CmdDrc(
     MagWindow *w,
     TxCommand *cmd)
 {
-    FILE        * fp;
     static int	drc_nth = 1;
     int		  option, result, radius;
     Rect	  rootArea, area;
@@ -4475,15 +4474,19 @@ CmdDrc(
 	case PRINTRULES:
 	    if (argc > 3) goto badusage;
 	    if (argc < 3)
-		fp = stdout;
+	    {
-	    else if ((fp = fopen (argv[2],"w")) == (FILE *) NULL)
+		DRCPrintRulesTable (stdout);
+	    }
+	    {
+	        FILE *fp = fopen (argv[2], "w");
+	        if (fp == NULL)
 		{
 		    TxError("Cannot write file %s\n", argv[2]);
 		    return;
 		}
 		DRCPrintRulesTable (fp);
-	    if (fp != stdout)
+		fclose(fp);
-		(void) fclose(fp);
+	    }
 	    break;
 
 	case RULESTATS:

commands/CmdTZ.c

@@ -1821,6 +1821,7 @@ CmdWire(
 				TxError("Bad coordinate pair at %s line %d\n",
 					cmd->tx_argv[4], i + 1);
 				freeMagic(plist);
+				fclose(pfile);
 				return;
 			    }
 

extract/ExtTest.c

@@ -119,7 +119,6 @@ ExtractTest(w, cmd)
     CellUse *selectedCell;
     Rect editArea;
     char *addr, *name;
-    FILE *f;
     typedef enum {  CLRDEBUG, CLRLENGTH, DRIVER, DUMP, INTERACTIONS,
 		    INTERCOUNT, EXTPARENTS, RECEIVER, SETDEBUG, SHOWDEBUG,
 		    SHOWPARENTS, SHOWTECH, STATS, STEP, TIME } cmdType;
@@ -215,37 +214,41 @@ ExtractTest(w, cmd)
 	    DBClearPaintPlane(interPlane);
 	    break;
 	case INTERCOUNT:
-	    f = stdout;
 	    halo = 1;
 	    if (cmd->tx_argc > 2)
 		halo = atoi(cmd->tx_argv[2]);
 	    if (cmd->tx_argc > 3)
 	    {
-		f = fopen(cmd->tx_argv[3], "w");
+		FILE *f = fopen(cmd->tx_argv[3], "w");
 		if (f == NULL)
 		{
 		    perror(cmd->tx_argv[3]);
 		    break;
 		}
-	    }
 		ExtInterCount((CellUse *) w->w_surfaceID, halo, f);
-	    if (f != stdout)
+		fclose(f);
-		(void) fclose(f);
+	    }
+	    else
+	    {
+		ExtInterCount((CellUse *) w->w_surfaceID, halo, stdout);
+	    }
 	    break;
 	case TIME:
-	    f = stdout;
 	    if (cmd->tx_argc > 2)
 	    {
-		f = fopen(cmd->tx_argv[2], "w");
+		FILE *f = fopen(cmd->tx_argv[2], "w");
 		if (f == NULL)
 		{
 		    perror(cmd->tx_argv[2]);
 		    break;
 		}
-	    }
 		ExtTimes((CellUse *) w->w_surfaceID, f);
-	    if (f != stdout)
+		fclose(f);
-		(void) fclose(f);
+	    }
+	    else
+	    {
+		ExtTimes((CellUse *) w->w_surfaceID, stdout);
+	    }
 	    break;
 	case EXTPARENTS:
 	    if (ToolGetEditBox(&editArea))
@@ -1105,6 +1108,7 @@ ExtDumpCaps(filename)
 	    return;
 	}
 	ExtDumpCapsToFile(f);
+	fclose(f);
 	return;
     }
 

graphics/grCMap.c

@@ -122,7 +122,6 @@ char *path;			/* a search path */
 char *libPath;			/* a library search path */
 
 {
-    FILE *f;
     int max, red, green, blue, newmax, argc, i;
     colorEntry *ce;
     char fullName[256], inputLine[128], colorName[100];
@@ -135,7 +134,7 @@ char *libPath;			/* a library search path */
     (void) sprintf(fullName, "%.80s.%.80s.%.80s", techStyle,
 	    dispType, monType);
 
-    f = PaOpen(fullName, "r", ".cmap", path, libPath, (char **) NULL);
+    FILE *f = PaOpen(fullName, "r", ".cmap", path, libPath, (char **) NULL);
     if (f == NULL)
     {
 	/* Check for original ".cmap1" file (prior to magic v. 7.2.27) */
@@ -163,7 +162,7 @@ char *libPath;			/* a library search path */
 
 	    TxError("Syntax error in color map file \"%s.cmap\"\n", fullName);
 	    TxError("Last color read was index %d\n", max);
-	    return FALSE;
+	    goto cleanup;
 	}
 	else
 	{
@@ -219,6 +218,11 @@ char *libPath;			/* a library search path */
 
     GrSetCMap();
     return TRUE;
+
+cleanup:
+    if(f)
+	fclose(f);
+    return FALSE;
 }
 
 

plot/plotPNM.c

@@ -576,7 +576,7 @@ PlotPNM(fileName, scx, layers, xMask, width)
 					 * plot, in pixels.
 					 */
 {
-    FILE *fp;
+    FILE *fp = NULL;
     Rect bbox;
     int bb_ysize, bb_xsize;
     int i, x, y, tile_ydelta;
@@ -920,6 +920,7 @@ PlotPNM(fileName, scx, layers, xMask, width)
 	}
 	fflush(rtl_args.outfile);
 	fclose(rtl_args.outfile);
+	rtl_args.outfile = NULL;
 	freeMagic(rtl_args.outbytes);
 
 	/* Run spooler */
@@ -932,7 +933,13 @@ PlotPNM(fileName, scx, layers, xMask, width)
     }
     else
 #endif
+    {
+        if(fp)
+        {
 	    fclose (fp);
+	    fp = NULL;
+        }
+    }
 
 done:
     PlotPNMdownsample = save_ds;
@@ -941,6 +948,15 @@ done:
     freeMagic(strip);
     freeMagic(lkstep);
     lkstep = NULL;
+#ifdef VERSATEC
+    if(rtl_args.outfile) /* theoretical fp leak */
+    {
+	fclose(rtl_args.outfile);
+	rtl_args.outfile = NULL;
+    }
+#endif
+    if(fp)
+	fclose(fp);
     return;
 }
 

plot/plotPS.c

@@ -1135,7 +1135,6 @@ PlotPS(fileName, scx, layers, xMask)
 {
     int xsize, ysize;
     float yscale;
-    FILE *infile;
     int i, j;
     int twidth, theight;
     char *fontptr, *fptr2, *fptr3;
@@ -1207,12 +1206,17 @@ PlotPS(fileName, scx, layers, xMask)
 
     /* Insert the prolog here */
 
-    infile = PaOpen("magicps", "r", ".pro", ".", SysLibPath, NULL);
+    {
+	FILE *infile = PaOpen("magicps", "r", ".pro", ".", SysLibPath, NULL);
 	if (infile != NULL)
+	{
 	    while(fgets(line_in, 99, infile) != NULL)
 		fputs(line_in, file);
+	    fclose(infile);
+	}
 	else
 	    fprintf(file, "\npostscript_prolog_is_missing\n\n");
+    }
 
     /* Insert the font definitions here. */
 

plot/plotVers.c

@@ -1353,7 +1353,7 @@ PlotVersatec(scx, layers, xMask, user_scale)
 		    {
 		        TxError("Warning:  No color versatec styles are defined"
 				" in the technology file!\nPlotting aborted.\n");
-			return;
+			goto error_close_only;
 		    }
 		    break;
 		default:
@@ -1372,7 +1372,7 @@ PlotVersatec(scx, layers, xMask, user_scale)
 		TxError("Warning:  No monochrome versatec styles are"
 			    " defined in the technology file!\nPlotting"
 			    " aborted.\n");
-		return;
+		goto error_close_only;
 	    }
 
 	    for ( ; curStyle != NULL; curStyle = curStyle->vs_next)
@@ -1479,6 +1479,10 @@ PlotVersatec(scx, layers, xMask, user_scale)
     TxError("\nVersatec plot aborted.\n");
     fclose(file);
     unlink(fileName);
+    return;
+
+error_close_only:
+    fclose(file);
 }
 
 #endif /* VERSATEC */

plow/PlowTest.c

@@ -143,7 +143,6 @@ PlowTest(w, cmd)
     Plane *plane;
     Edge edge;
     Tile *tp;
-    FILE *f;
 
     if (!ToolGetEditBox(&editArea) || !ToolGetBox(&rootBoxDef, &rootBox))
 	return;
@@ -244,19 +243,21 @@ PlowTest(w, cmd)
 	    plowYankDef = saveDef;
 	    break;
 	case PC_TECHSHOW:
-	    f = stdout;
 	    if (cmd->tx_argc >= 3)
 	    {
-		f = fopen(cmd->tx_argv[2], "w");
+		FILE *f = fopen(cmd->tx_argv[2], "w");
 		if (f == NULL)
 		{
 		    perror(cmd->tx_argv[2]);
 		    break;
 		}
-	    }
 		plowTechShow(f);
-	    if (f != stdout)
+		fclose(f);
-		(void) fclose(f);
+	    }
+	    else
+	    {
+		plowTechShow(stdout);
+	    }
 	    break;
 	case PC_WIDTH:
 	    if (cmd->tx_argc < 3)

resis/ResReadSim.c

@@ -216,6 +216,7 @@ ResReadSim(simfile, fetproc, capproc, resproc, attrproc, mergeproc, subproc)
 	if (result != 0)
 	{
 	    TxError("Error in sim file %s\n", line[0]);
+	    fclose(fp);
 	    return 1;
 	}
     }
@@ -922,6 +923,7 @@ ResSimProcessDrivePoints(filename)
 	node->drivepoint.p_y = atoi(line[RES_EXT_ATTR_Y]);
 	node->rs_ttype = DBTechNoisyNameType(line[RES_EXT_ATTR_TILE]);
     }
+    fclose(fp);
 }
 
 /*
@@ -982,6 +984,7 @@ ResSimProcessFixPoints(filename)
 	thisfix->fp_tile = NULL;
 	strcpy(thisfix->fp_name, label);
     }
+    fclose(fp);
 }
 
 

router/rtrCmd.c

@@ -340,7 +340,9 @@ badWarn:
 	    if (!ToolGetEditBox(&editArea))
 		return;
 	    channame = cmd->tx_argv[2];
-	    f = stdout;
+	    {
+		bool need_close;
+		FILE *f;
 		if (cmd->tx_argc == 4)
 		{
 		    f = fopen(cmd->tx_argv[3], "w");
@@ -349,6 +351,12 @@ badWarn:
 			perror(cmd->tx_argv[3]);
 			return;
 		    }
+		    need_close = TRUE;
+		}
+		else
+		{
+		    f = stdout;
+		    need_close = FALSE;
 		}
 		if (channame[0] == 'h') GAGenChans(CHAN_HRIVER, &editArea, f);
 		else if (channame[0] == 'v') GAGenChans(CHAN_VRIVER, &editArea, f);
@@ -357,8 +365,9 @@ badWarn:
 		    TxError("Unrecognized channel type: %s\n", channame);
 		    TxError("Legal types are \"h\" or \"v\"\n");
 		}
-	    if (f != stdout)
+		if (need_close)
 		    (void) fclose(f);
+	    }
 	    break;
 	case CHANNEL:
 	    channame = (char *) NULL;