Fix bug decoding empty arrays and maps (#16)
diff --git a/src/qcbor_decode.c b/src/qcbor_decode.c
index 9599b07..c35a29d 100644
--- a/src/qcbor_decode.c
+++ b/src/qcbor_decode.c
@@ -42,6 +42,7 @@
when who what, where, why
-------- ---- ---------------------------------------------------
+ 09/07/19 llundblade Fix bug decoding empty arrays and maps
07/31/19 llundblade Decode error fixes for some not-well-formed CBOR
07/31/19 llundblade New error code for better end of data handling
02/17/19 llundblade Fixed: QCBORItem.u{Data|Label}Alloc when bAllStrings set
@@ -129,28 +130,27 @@
// Called on every single item except breaks including the opening of a map/array
inline static void DecodeNesting_DecrementCount(QCBORDecodeNesting *pNesting)
{
- if(!DecodeNesting_IsNested(pNesting)) {
- // at top level where there is no tracking
- return;
- }
+ while(DecodeNesting_IsNested(pNesting)) {
+ // Not at the top level, so there is decrementing to be done.
- if(DecodeNesting_IsIndefiniteLength(pNesting)) {
- // There is no count for indefinite length arrays/maps
- return;
- }
-
- // Decrement the count of items in this array/map
- pNesting->pCurrent->uCount--;
-
- // Pop up nesting levels if the counts at the levels are zero
- while(DecodeNesting_IsNested(pNesting) && 0 == pNesting->pCurrent->uCount) {
- pNesting->pCurrent--;
if(!DecodeNesting_IsIndefiniteLength(pNesting)) {
+ // Decrement the current nesting level if it is not indefinite.
pNesting->pCurrent->uCount--;
}
+
+ if(pNesting->pCurrent->uCount != 0) {
+ // Did not close out an array or map, so nothing further
+ break;
+ }
+
+ // Closed out an array or map so level up
+ pNesting->pCurrent--;
+
+ // Continue with loop to see if closing out this doesn't close out more
}
}
+
// Called on every map/array
inline static QCBORError DecodeNesting_Descend(QCBORDecodeNesting *pNesting, QCBORItem *pItem)
{
@@ -1098,7 +1098,10 @@
// Maps and arrays do count in as items in the map/array that encloses
// them so a decrement needs to be done for them too, but that is done
// only when all the items in them have been processed, not when they
- // are opened.
+ // are opened with the exception of an empty map or array.
+ if(pDecodedItem->val.uCount == 0) {
+ DecodeNesting_DecrementCount(&(me->nesting));
+ }
} else {
// Decrement the count of items in the enclosing map/array
// If the count in the enclosing map/array goes to zero, that
diff --git a/test/qcbor_decode_tests.c b/test/qcbor_decode_tests.c
index 8a79bd8..3c17d0a 100644
--- a/test/qcbor_decode_tests.c
+++ b/test/qcbor_decode_tests.c
@@ -593,6 +593,149 @@
}
+/*
+ [
+ 0,
+ [],
+ [
+ [],
+ [
+ 0
+ ],
+ {},
+ {
+ 1: {},
+ 2: {},
+ 3: []
+ }
+ ]
+ ]
+ */
+static uint8_t sEmpties[] = {0x83, 0x00, 0x80, 0x84, 0x80, 0x81, 0x00, 0xa0,
+ 0xa3, 0x01, 0xa0, 0x02, 0xa0, 0x03, 0x80};
+
+int EmptyMapsAndArraysTest()
+{
+ QCBORDecodeContext DCtx;
+ QCBORItem Item;
+
+ QCBORDecode_Init(&DCtx, UsefulBuf_FROM_BYTE_ARRAY_LITERAL(sEmpties), QCBOR_DECODE_MODE_NORMAL);
+
+ // Array with 3 items
+ if(QCBORDecode_GetNext(&DCtx, &Item) != 0 ||
+ Item.uDataType != QCBOR_TYPE_ARRAY ||
+ Item.uNestingLevel != 0 ||
+ Item.uNextNestLevel != 1 ||
+ Item.val.uCount != 3) {
+ return -1;
+ }
+
+ // An integer 0
+ if(QCBORDecode_GetNext(&DCtx, &Item) != 0 ||
+ Item.uDataType != QCBOR_TYPE_INT64 ||
+ Item.uNestingLevel != 1 ||
+ Item.uNextNestLevel != 1 ||
+ Item.val.uint64 != 0) {
+ return -2;
+ }
+
+ // An empty array
+ if(QCBORDecode_GetNext(&DCtx, &Item) != 0 ||
+ Item.uDataType != QCBOR_TYPE_ARRAY ||
+ Item.uNestingLevel != 1 ||
+ Item.uNextNestLevel != 1 ||
+ Item.val.uCount != 0) {
+ return -3;
+ }
+
+ // An array with 4 items
+ if(QCBORDecode_GetNext(&DCtx, &Item) != 0 ||
+ Item.uDataType != QCBOR_TYPE_ARRAY ||
+ Item.uNestingLevel != 1 ||
+ Item.uNextNestLevel != 2 ||
+ Item.val.uCount != 4) {
+ return -4;
+ }
+
+ // An empty array
+ if(QCBORDecode_GetNext(&DCtx, &Item) != 0 ||
+ Item.uDataType != QCBOR_TYPE_ARRAY ||
+ Item.uNestingLevel != 2 ||
+ Item.uNextNestLevel != 2 ||
+ Item.val.uCount != 0) {
+ return -5;
+ }
+
+ // An array with 1 item
+ if(QCBORDecode_GetNext(&DCtx, &Item) != 0 ||
+ Item.uDataType != QCBOR_TYPE_ARRAY ||
+ Item.uNestingLevel != 2 ||
+ Item.uNextNestLevel != 3 ||
+ Item.val.uCount != 1) {
+ return -6;
+ }
+
+ // An integer 0
+ if(QCBORDecode_GetNext(&DCtx, &Item) != 0 ||
+ Item.uDataType != QCBOR_TYPE_INT64 ||
+ Item.uNestingLevel != 3 ||
+ Item.uNextNestLevel != 2 ||
+ Item.val.uint64 != 0) {
+ return -7;
+ }
+
+ // An empty map
+ if(QCBORDecode_GetNext(&DCtx, &Item) != 0 ||
+ Item.uDataType != QCBOR_TYPE_MAP ||
+ Item.uNestingLevel != 2 ||
+ Item.uNextNestLevel != 2 ||
+ Item.val.uCount != 0) {
+ return -8;
+ }
+
+ // An map with 3 items
+ if(QCBORDecode_GetNext(&DCtx, &Item) != 0 ||
+ Item.uDataType != QCBOR_TYPE_MAP ||
+ Item.uNestingLevel != 2 ||
+ Item.uNextNestLevel != 3 ||
+ Item.val.uCount != 3) {
+ return -9;
+ }
+
+ // An empty map
+ if(QCBORDecode_GetNext(&DCtx, &Item) != 0 ||
+ Item.uDataType != QCBOR_TYPE_MAP ||
+ Item.uNestingLevel != 3 ||
+ Item.uNextNestLevel != 3 ||
+ Item.val.uCount != 0) {
+ return -10;
+ }
+
+ // An empty map
+ if(QCBORDecode_GetNext(&DCtx, &Item) != 0 ||
+ Item.uDataType != QCBOR_TYPE_MAP ||
+ Item.uNestingLevel != 3 ||
+ Item.uNextNestLevel != 3 ||
+ Item.val.uCount != 0) {
+ return -11;
+ }
+
+ // An empty array
+ if(QCBORDecode_GetNext(&DCtx, &Item) != 0 ||
+ Item.uDataType != QCBOR_TYPE_ARRAY ||
+ Item.uNestingLevel != 3 ||
+ Item.uNextNestLevel != 0 ||
+ Item.val.uCount != 0) {
+ return -12;
+ }
+
+ if(QCBORDecode_Finish(&DCtx) != QCBOR_SUCCESS) {
+ return -13;
+ }
+
+ return 0;
+}
+
static uint8_t spDeepArrays[] = {0x81, 0x81, 0x81, 0x81, 0x81, 0x81, 0x81, 0x81, 0x81, 0x80};
diff --git a/test/qcbor_decode_tests.h b/test/qcbor_decode_tests.h
index 6159c8b..dfac338 100644
--- a/test/qcbor_decode_tests.h
+++ b/test/qcbor_decode_tests.h
@@ -67,6 +67,11 @@
*/
int SimpleArrayTest(void);
+/*
+ Tests with empty maps and arrays
+ */
+int EmptyMapsAndArraysTest(void);
+
/*
Make sure a maximally deep array can be parsed and that the
diff --git a/test/run_tests.c b/test/run_tests.c
index 374b40e..becd545 100644
--- a/test/run_tests.c
+++ b/test/run_tests.c
@@ -100,6 +100,7 @@
test_entry s_tests[] = {
+ TEST_ENTRY(EmptyMapsAndArraysTest),
TEST_ENTRY(NotWellFormedTests),
TEST_ENTRY(ParseMapAsArrayTest),
TEST_ENTRY(AllocAllStringsTest),