[HDFS-15935] Use memcpy for copying non-null terminated string

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 3.4.0
• Fix Version/s: 3.4.0
• Component/s: libhdfs++
• Labels: pull-request-available
• Hadoop Flags: Reviewed
• Assignee: Gautham Banasandra
• Reporter: Gautham Banasandra
• Due: 30/Mar/21
• Created: 29/Mar/21 17:34
• Updated: 29/Mar/21 17:39
• Resolved: 29/Mar/21 17:39

Description

We currently get a warning while compiling HDFS native client -

[WARNING] /usr/include/x86_64-linux-gnu/bits/string_fortified.h:106:10: warning: '__builtin_strncpy' output truncated before terminating nul copying as many bytes from a string as its length [-Wstringop-truncation]

The scenario here is such that the copied string is deliberately not null terminated, so that we append a custom character appropriately. The warning reported by strncpy is valid, but not applicable in this scenario. Thus, we need to use memcpy which doesn't mind if the string is null terminated or not.

Issue Links

• is related to: HDFS-15922 Use memcpy for copying non-null terminated string in jni_helper.c
• links to: GitHub Pull Request #2827