[DRE-maint] Bug#826590: ruby-passenger: passenger-memory-stats doesn't display Total counter in Jessie

[Alex Kiousis]

Source: ruby-passenger
Version: 4.0.53-1
Severity: normal

Dear Maintainer,

We use the script passenger-memory-stats as a munin plugin source. When
upgrading from Wheezy to Jessie we saw that the output of the script
didn't include the footers with the total numbers (but otherwise the
script run fine).

E.g. this was missing:

### Processes: 15
### Total private dirty RSS: 1310.94 MB


After some digging around i ended up with this:
/usr/sbin/passenger-memory-stats calls
AdminTools::MemoryStats:platform_provides_private_dirty_rss_information
which returns PlatformInfo:os_name which in turn looksup
rb_config['target_os'] (on Wheezy it used RUBY_PLATFORM).
This (/usr/lib/x86_64-linux-gnu/ruby/2.1.0/rbconfig.rb) returns
"linux-gnu" on Ruby 2.1.0 and "linux" on previous versions:

p4.grnet.gr:~# locate rbconfig.rb | xargs -I{} sh -c "echo {} && grep
target_os {}"
/usr/lib/ruby/1.8/x86_64-linux/rbconfig.rb
  CONFIG["target_os"] = "linux"
/usr/lib/ruby/1.9.1/x86_64-linux/rbconfig.rb
  CONFIG["target_os"] = "linux"
/usr/lib/x86_64-linux-gnu/ruby/2.1.0/rbconfig.rb
  CONFIG["target_os"] = "linux-gnu"

I believe the problem is in 'platform_info/operating_system.rb'.
Based on the comment on line 32:

'# Linux is always identified as"linux".'

Upstream code is now like this (line 39):

 elsif rb_config['target_os'] =~ /^linux-/

the shipped script contains this (line 37):

 elsif rb_config['target_os'] == "linux-"

So i believe this is a bug that is fixed upstream but occurs in the
currently packaged version.

-- System Information:
Debian Release: 8.5
  APT prefers stable
  APT policy: (500, 'stable')
Architecture: amd64 (x86_64)
Foreign Architectures: i386

Kernel: Linux 3.16.0-4-amd64 (SMP w/4 CPU cores)
Locale: LANG=en_US.UTF-8, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash
Init: systemd (via /run/systemd/system)