arrays[arrays] is a special case of "INDEX" that actually returns an
array containing the indices in which the array that is being indexed
contains the start of the key array.
So array keys, for array values, are a kind of key that can be "got",
but not "set". jv_setpath() was not freeing the value it "got" from
indexing that key, in case the following "set" on that key failed,
resulting in a leak.
$ ./jq -n '[] | setpath([[1]]; 1)'
jq: error (at <unknown>): Cannot update field at array index of array
=================================================================
==953483==ERROR: LeakSanitizer: detected memory leaks
Direct leak of 272 byte(s) in 1 object(s) allocated from:
#0 0x725f4d4e1359 in __interceptor_malloc /usr/src/debug/gcc/gcc/libsanitizer/asan/asan_malloc_linux.cpp:69
#1 0x5ec17b1a7438 in jv_mem_alloc src/jv_alloc.c:141
SUMMARY: AddressSanitizer: 272 byte(s) leaked in 1 allocation(s).
Fixes https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=66061
It does not matter much since they most likely just get multiplied
together, but some compilers would complain about this if these were
calls to calloc.
* Fix memory leak for has(nan)
jv_array_get() used to be responsible of freeing the input array, but
since b5c4c3d67d, it is no longer called
if the key is nan. We need to free it manually to avoid leaking the
array.
* Parse nan in JSON as NaN instead of triggering a parse error
Fixes#2021
We need to be careful to not grab an extra reference when mutating
data structures because that means we make extra copies. Doing that
every time in `jv_setpath()` is really painful, as that function is used
in `_modify/2`, which is used in `|=` and all modify-assign operators.
`_modify` also grabs additional references, so this is not the only fix
needed for the modify-assign operators to not be accidentally quadratic.
Extend jv_number to use decNumber for storing number literals. Any math
operations on the numbers will truncate them to double precision.
Comparisons when both numbers are literal numbers will compare them
without truncation.
Delay conversion of numbers to doubles until a math operation is performed,
to preserve precision. A literal jv_number will only need conversion to
double once, and will reuse the resultant double on subsequent
conversions.
Outputting literal jv_numbers preserves the original precision.
Add strong pthread requirement to manage contexts/allocations for
converting numbers between their decNumber, string, and double formats.
Emanuele Torre