fix corruption of MOVE DISP TO PACKED, bug introduced with [r5128]

libcob/move.c (cob_move_display_to_packed): fix data corruption caused by packing one extra digit from the input display field
lefessan · Jul 28, 2023 · 6f07531 · 6f07531
1 parent 74d62e2
commit 6f07531
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Showing 3 changed files with 37 additions and 7 deletions.
diff --git a/libcob/ChangeLog b/libcob/ChangeLog
@@ -1,4 +1,9 @@
 
+2023-07-27  Chuck Haatvedt <[email protected]>
+
+	* move.c (cob_move_display_to_packed): fix data corruption caused
+	  by packing one extra digit from the input display field
+
 2023-07-24  Simon Sobisch <[email protected]>
 
 	* fileio.c: only check -1 as invalid fd; return fileio status for

diff --git a/libcob/move.c b/libcob/move.c
@@ -554,6 +554,10 @@ cob_move_display_to_packed (cob_field *f1, cob_field *f2)
 				p += 2;
 			}
 		}
+		/* clean bottom nibble if we packed one extra digit past the end of the input */
+		if (p > p_end) {
+			*(q - 1) &= 0xf0;
+		}
 	}
 
 	COB_PUT_SIGN_ADJUSTED (f1, sign);

diff --git a/tests/testsuite.src/data_packed.at b/tests/testsuite.src/data_packed.at
@@ -830,13 +830,34 @@ AT_DATA([prog.cob], [
        PROGRAM-ID.      prog.
        DATA             DIVISION.
        WORKING-STORAGE  SECTION.
-       01  D-S99V99     PIC S99V99 DISPLAY VALUE  1.23.
-       01  D-N99V99     PIC S99V99 DISPLAY VALUE -1.32.
-       01  D-9V99       PIC   9V99 DISPLAY VALUE  1.1.
-       01  D-S99        PIC S99    DISPLAY VALUE  12.
-       01  D-99         PIC  99    DISPLAY VALUE  2.
-       01  D-P99        PIC P99    DISPLAY VALUE  0.02.
-       01  D-9PP        PIC 9PP    DISPLAY VALUE  200.
+       01  FILLER.
+        05 FILLER PIC XX VALUE '12'.
+        05 D-S99V99     PIC S99V99 DISPLAY VALUE  1.23.
+        05 FILLER PIC XX VALUE '34'.
+       01  FILLER.
+        05 FILLER PIC XX VALUE '12'.
+        05 D-N99V99     PIC S99V99 DISPLAY VALUE -1.32.
+        05 FILLER PIC XX VALUE '34'.
+       01  FILLER.
+        05 FILLER PIC XX VALUE '12'.
+        05 D-9V99       PIC   9V99 DISPLAY VALUE  1.1.
+        05 FILLER PIC XX VALUE '34'.
+       01  FILLER.
+        05 FILLER PIC XX VALUE '12'.
+        05 D-S99        PIC S99    DISPLAY VALUE  12.
+        05 FILLER PIC XX VALUE '34'.
+       01  FILLER.
+        05 FILLER PIC XX VALUE '12'.
+        05 D-99         PIC  99    DISPLAY VALUE  2.
+        05 FILLER PIC XX VALUE '34'.
+       01  FILLER.
+        05 FILLER PIC XX VALUE '12'.
+        05 D-P99        PIC P99    DISPLAY VALUE  0.02.
+        05 FILLER PIC XX VALUE '34'.
+       01  FILLER.
+        05 FILLER PIC XX VALUE '12'.
+        05 D-9PP        PIC 9PP    DISPLAY VALUE  200.
+        05 FILLER PIC XX VALUE '34'.
        01  P-S99V99     PIC S99V99 PACKED-DECIMAL.
        01  P-99V9       PIC  99V9  PACKED-DECIMAL.
        01  P-S999       PIC S999   PACKED-DECIMAL.