[LU-4107] luser_user.h is not C++ compatible

• Status: Resolved
• Project: Lustre
• Affects Version/s: Lustre 2.4.1
• Fix Version/s: Lustre 2.6.0
• Type: Bug
• Priority: Minor
• Reporter: Ned Bass
• Assignee: Minh Diep
• Resolution: Fixed
• Severity: 3

Description

Some users would like to include lustre_user.h or lustreapi.h in C++ applications. There are a few compatibility issues currently preventing this.

$ cat a.c
#include <lustre/lustre_user.h>
$ g++ -c a.c
In file included from a.c:1:
/usr/include/lustre/lustre_user.h:185: error: 'struct ost_id::<anonymous union>::ostid' invalid; an anonymous union can only have non-static data members
/usr/include/lustre/lustre_user.h: In function 'hsm_event hsm_get_cl_event(__u16)':
/usr/include/lustre/lustre_user.h:728: error: invalid conversion from 'int' to 'hsm_event'
/usr/include/lustre/lustre_user.h: In function 'int hur_len(hsm_user_request*)':
/usr/include/lustre/lustre_user.h:1002: error: 'hur' cannot appear in a constant-expression
/usr/include/lustre/lustre_user.h:1002: error: '->' cannot appear in a constant-expression
/usr/include/lustre/lustre_user.h:1002: error: '.' cannot appear in a constant-expression
/usr/include/lustre/lustre_user.h: In function 'char* hai_dump_data_field(hsm_action_item*, char*, int)':
/usr/include/lustre/lustre_user.h:1068: error: 'snprintf' was not declared in this scope

While we're at it, we may also want to clean up these warnings which are normally suppressed because they're in a system header.

$ g++ -Wall -Wsystem-headers -c a.c
In file included from a.c:1:
/usr/include/lustre/lustre_user.h:185: error: 'struct ost_id::<anonymous union>::ostid' invalid; an anonymous union can only have non-static data members
/usr/include/lustre/lustre_user.h: In function 'hsm_event hsm_get_cl_event(__u16)':
/usr/include/lustre/lustre_user.h:728: error: invalid conversion from 'int' to 'hsm_event'
/usr/include/lustre/lustre_user.h: In function 'char* hsm_progress_state2name(hsm_progress_states)':
/usr/include/lustre/lustre_user.h:889: warning: deprecated conversion from string constant to 'char*'
/usr/include/lustre/lustre_user.h:890: warning: deprecated conversion from string constant to 'char*'
/usr/include/lustre/lustre_user.h:891: warning: deprecated conversion from string constant to 'char*'
/usr/include/lustre/lustre_user.h:892: warning: deprecated conversion from string constant to 'char*'
/usr/include/lustre/lustre_user.h: In function 'char* hsm_user_action2name(hsm_user_action)':
/usr/include/lustre/lustre_user.h:951: warning: deprecated conversion from string constant to 'char*'
/usr/include/lustre/lustre_user.h:952: warning: deprecated conversion from string constant to 'char*'
/usr/include/lustre/lustre_user.h:953: warning: deprecated conversion from string constant to 'char*'
/usr/include/lustre/lustre_user.h:954: warning: deprecated conversion from string constant to 'char*'
/usr/include/lustre/lustre_user.h:955: warning: deprecated conversion from string constant to 'char*'
/usr/include/lustre/lustre_user.h:956: warning: deprecated conversion from string constant to 'char*'
/usr/include/lustre/lustre_user.h:957: warning: deprecated conversion from string constant to 'char*'
/usr/include/lustre/lustre_user.h: In function 'int hur_len(hsm_user_request*)':
/usr/include/lustre/lustre_user.h:1002: error: 'hur' cannot appear in a constant-expression
/usr/include/lustre/lustre_user.h:1002: error: '->' cannot appear in a constant-expression
/usr/include/lustre/lustre_user.h:1002: error: '.' cannot appear in a constant-expression
/usr/include/lustre/lustre_user.h: In function 'char* hsm_copytool_action2name(hsm_copytool_action)':
/usr/include/lustre/lustre_user.h:1025: warning: deprecated conversion from string constant to 'char*'
/usr/include/lustre/lustre_user.h:1026: warning: deprecated conversion from string constant to 'char*'
/usr/include/lustre/lustre_user.h:1027: warning: deprecated conversion from string constant to 'char*'
/usr/include/lustre/lustre_user.h:1028: warning: deprecated conversion from string constant to 'char*'
/usr/include/lustre/lustre_user.h:1029: warning: deprecated conversion from string constant to 'char*'
/usr/include/lustre/lustre_user.h:1030: warning: deprecated conversion from string constant to 'char*'
/usr/include/lustre/lustre_user.h: In function 'char* hai_dump_data_field(hsm_action_item*, char*, int)':
/usr/include/lustre/lustre_user.h:1068: error: 'snprintf' was not declared in this scope
/usr/include/lustre/lustre_user.h: In function 'int hal_size(hsm_action_list*)':
/usr/include/lustre/lustre_user.h:1121: warning: comparison between signed and unsigned integer expressions

Comments

[Peter Jones]

Minh will help with this one

[Andreas Dilger]

Is this a regression compared to lustre_user.h in 2.4, or is this a new application using it for the first time?

[Ned Bass]

It's a new app, so not a regression. In fact, they were trying to build against Lustre 2.1, and got a slightly different set of errors.

/usr/include/lustre/lustre_user.h: In function 'hsm_event hsm_get_cl_event(__u16)':
/usr/include/lustre/lustre_user.h:565: error: invalid conversion from '__u16' to 'hsm_event'
/usr/include/lustre/lustre_user.h: In function 'int hur_len(hsm_user_request*)':
/usr/include/lustre/lustre_user.h:759: error: invalid use of 'void'
/usr/include/lustre/lustre_user.h: In function 'char* hai_dump_data_field(hsm_action_item*, char*, int)':
/usr/include/lustre/lustre_user.h:823: error: 'snprintf' was not declared in this scope

[Minh Diep]

http://review.whamcloud.com/#/c/8033/

[Peter Jones]

Landed for 2.6