Обсуждение: [patch]overallocate memory for curly braces in array_out
Hi,
Attached is a patch that fixes a bug
for miscounting total number of curly braces in output string in array_out.
Example1
{{1,2,3},{4,5,6}} -> dims[0] = 2, dims[1]= 3
- Without the patch
8
- After
3
Example2
N size one-dimensional array -> dims[0] = N
- Without the patch
N
- After
1
I used gdb to confirm the above behavior.
Cheers,
Keiichi Hirobe
Вложения
Keiichi Hirobe <chalenge.akane@gmail.com> writes:
> Attached is a patch that fixes a bug
> for miscounting total number of curly braces in output string in array_out.
Wow, good catch!
Testing this, I found there's a second way in which the space calculation
is off: it always allocated one more byte than required, as a result of
counting one more comma than is really required. That's not nearly as
significant as the curly-brace miscount, but it still got in the way of
doing this:
*** 1234,1239 ****
--- 1243,1251 ----
#undef APPENDSTR
#undef APPENDCHAR
+ /* Assert that we calculated the string length accurately */
+ Assert(overall_length == (p - retval + 1));
+
pfree(values);
pfree(needquotes);
which seemed to me like a good idea now that we know this code isn't
so perfect as all that.
Will push shortly.
regards, tom lane
Hi,
Thanks for the reply.
I am not sure whether to fix another bug, but I fixed and I attached a new patch,
please check it.
Please note that I inserted a line for updating "overall_length" at line 1185.
I checked below case.
select ARRAY[ARRAY[1,2,3],ARRAY[4,5,6]]; (regular case)
select '[3:4][2:4]={{1,2,3},{4,5,6}}'::_int4; (needdims case)
select ARRAY['a"bc','def']; (needquote case)
Cheers,
Keiichi Hirobe
2018年9月24日(月) 23:46 Tom Lane <tgl@sss.pgh.pa.us>:
Keiichi Hirobe <chalenge.akane@gmail.com> writes:
> Attached is a patch that fixes a bug
> for miscounting total number of curly braces in output string in array_out.
Wow, good catch!
Testing this, I found there's a second way in which the space calculation
is off: it always allocated one more byte than required, as a result of
counting one more comma than is really required. That's not nearly as
significant as the curly-brace miscount, but it still got in the way of
doing this:
*** 1234,1239 ****
--- 1243,1251 ----
#undef APPENDSTR
#undef APPENDCHAR
+ /* Assert that we calculated the string length accurately */
+ Assert(overall_length == (p - retval + 1));
+
pfree(values);
pfree(needquotes);
which seemed to me like a good idea now that we know this code isn't
so perfect as all that.
Will push shortly.
regards, tom lane
Вложения
Keiichi Hirobe <chalenge.akane@gmail.com> writes: > I am not sure whether to fix another bug, but I fixed and I attached a new > patch, > please check it. I think this duplicates what I already committed at https://git.postgresql.org/gitweb/?p=postgresql.git;a=commitdiff;h=87d9bbca13f9c6b8f6ee986f0e399cb83bd731d4 regards, tom lane
Sorry, I did not notice that you had already pushed it.
Thank you for quick action.
Cheers,
Keiichi Hirobe
2018年9月28日(金) 9:23 Tom Lane <tgl@sss.pgh.pa.us>:
Keiichi Hirobe <chalenge.akane@gmail.com> writes:
> I am not sure whether to fix another bug, but I fixed and I attached a new
> patch,
> please check it.
I think this duplicates what I already committed at
https://git.postgresql.org/gitweb/?p=postgresql.git;a=commitdiff;h=87d9bbca13f9c6b8f6ee986f0e399cb83bd731d4
regards, tom lane