Don't ignore buffer length when printing #1768
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As a left-over from when Pony strings where null terminated, pony_os_std_print wasn't checking the length of the passed in buffer and would print the entire buffer and beyond until it hit a null terminator. This PR fixes that issue so that we will now correctly only print `len` elements from the buffer.
SeanTAllen
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changelog - fixed
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I'd consider this a high priority bug fix that should trigger a release and have marked as such. @ponylang/committer any disagreement? |
SeanTAllen
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triggers release
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Agree. |
| @@ -512,7 +512,7 @@ PONY_API void pony_os_std_print(FILE* fp, char* buffer, size_t len) | |||
| if(len == 0) | |||
| return; | |||
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| fprintf(fp, "%s\n", buffer); | |||
| fprintf(fp, "%*.*s\n", (int)len, (int)len, buffer); | |||
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I'd expect you to only need %*s\n here, does that not work?
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Never mind, I saw the note you sent about the first not working. I'll merge it.
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This formatting string creates a problem for certain Strings. See also https://ponylang.zulipchat.com/#narrow/stream/189985-beginner-help/topic/Bug.20in.20String.2Efrom_array.28.29.20.3F/near/286809387
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Sorry, folks - I totally missed this one when doing the "allow strings to not be null terminated" PR. I saw that the FFI call to |
When printing via `StdStream.print` strings containing the null terminator, we were just printing the string until the null terminator and replacing the unprinted characters by padding the printed string with space characters. This behavior made `String.size()` inconsistent with what `fprintf` was really printing. This behavior has been introduced in #1768, which ensure we respected the buffer size. Closes #4171
As a left-over from when Pony strings where null terminated,
pony_os_std_print wasn't checking the length of the passed in
buffer and would print the entire buffer and beyond until it
hit a null terminator.
This PR fixes that issue so that we will now correctly only
print
lenelements from the buffer.