RFR: 8261949: fileStream::readln returns incorrect line string

[Daniel D.Daugherty]

On Thu, 18 Feb 2021 12:31:29 GMT, Yang Yi <github.com+5010047+kelthuzadx at openjdk.org> wrote:

> When the last line does not contain a NEWLINE character, fileStream::readln would read
> truncated line string:
> 
> $ cat file_content:
> AA
> BB
> CC<EOF>
> 
> fileStream::readln result:
> "AA"
> "BB"
> "C"
> 
> This patch address this problem, it works for Posix and Windows since the last character
> of these systems is always '\n'.

Changes requested by dcubed (Reviewer).

src/hotspot/share/utilities/ostream.cpp line 593:

> 591:     ret = ::fgets(data, count, _file);
> 592:     // Get rid of annoying \n char only if it presents, it works for Posix
> 593:     // and Windows since the last character of these systems is always '\n'

s/of these/on these/
Please end the comment with a period.

src/hotspot/share/utilities/ostream.cpp line 595:

> 593:     // and Windows since the last character of these systems is always '\n'
> 594:     if (data[::strlen(data)-1] == '\n') {
> 595:       data[::strlen(data)-1] = '\0';

Perhaps:
    size_t last_char = ::strlen(data) - 1;
    if (last_char >= 0 && data[last_char] == '\n') {
      data[last_char] = '\0';

-------------

PR: https://git.openjdk.java.net/jdk/pull/2626