APR::Status - Perl Interface to the APR_STATUS_IS_* macros
use APR::Status (); eval { $obj->mp_method() }; if ($@ && $ref $@ eq 'APR::Error' && APR::Status::is_EAGAIN($@)) { # APR_STATUS_IS_EAGAIN(s) of apr_errno.h is satisfied }
An interface to apr_errno.h composite error codes.
As discussed in the APR::Error manpage, it is possible to handle APR/Apache/mod_perl exceptions in the following way:
APR::Error
eval { $obj->mp_method() }; if ($@ && $ref $@ eq 'APR::Error' && $@ == $some_code) warn "handled exception: $@"; }
However, in cases where $some_code is an APR::Const constant, there may be more than one condition satisfying the intent of this exception. For this purpose the APR C library provides in apr_errno.h a series of macros, APR_STATUS_IS_*, which are the recommended way to check for such conditions. For example, the APR_STATUS_IS_EAGAIN macro is defined as
$some_code
APR_STATUS_IS_*
APR_STATUS_IS_EAGAIN
#define APR_STATUS_IS_EAGAIN(s) ((s) == APR_EAGAIN \ || (s) == APR_OS_START_SYSERR + ERROR_NO_DATA \ || (s) == APR_OS_START_SYSERR + SOCEWOULDBLOCK \ || (s) == APR_OS_START_SYSERR + ERROR_LOCK_VIOLATION)
The purpose of APR::Status is to provide functions corresponding to these macros.
APR::Status
is_EACCES
Check if the error is matching EACCES and its variants (corresponds to the APR_STATUS_IS_EACCES macro).
EACCES
APR_STATUS_IS_EACCES
$status = APR::Status::is_EACCES($error_code);
$error_code
APR::Error object
The error code or to check, normally $@ blessed into APR::Error object.
$@
$status
An example of using is_EACCES is when reading the contents of a file where access may be forbidden:
eval { $obj->slurp_filename(0) }; if ($@) { return Apache2::Const::FORBIDDEN if ref $@ eq 'APR::Error' && APR::Status::is_EACCES($@); die $@; }
Due to possible variants in conditions matching EACCES, the use of this function is recommended for checking error codes against this value, rather than just using APR::Const::EACCES directly.
APR::Const::EACCES
is_EAGAIN
Check if the error is matching EAGAIN and its variants (corresponds to the APR_STATUS_IS_EAGAIN macro).
EAGAIN
$status = APR::Status::is_EAGAIN($error_code);
For example, here is how you may want to handle socket read exceptions and do retries:
use APR::Status (); # .... my $tries = 0; my $buffer; RETRY: my $rlen = eval { $socket->recv($buffer, SIZE) }; if ($@ && ref($@) && APR::Status::is_EAGAIN($@)) { if ($tries++ < 3) { goto RETRY; } else { # do something else } } else { die "eval block has failed: $@"; }
Notice that just checking against APR::Const::EAGAIN may work on some Unices, but then it will certainly break on win32. Thefore make sure to use this macro and not APR::Const::EAGAIN unless you know what you are doing.
APR::Const::EAGAIN
is_ENOENT
Check if the error is matching ENOENT and its variants (corresponds to the APR_STATUS_IS_ENOENT macro).
ENOENT
APR_STATUS_IS_ENOENT
$status = APR::Status::is_ENOENT($error_code);
An example of using is_ENOENT is when reading the contents of a file which may not exist:
eval { $obj->slurp_filename(0) }; if ($@) { return Apache2::Const::NOT_FOUND if ref $@ eq 'APR::Error' && APR::Status::is_ENOENT($@); die $@; }
Due to possible variants in conditions matching ENOENT, the use of this function is recommended for checking error codes against this value, rather than just using APR::Const::ENOENT directly.
APR::Const::ENOENT
is_EOF
Check if the error is matching EOF and its variants (corresponds to the APR_STATUS_IS_EOF macro).
EOF
APR_STATUS_IS_EOF
$status = APR::Status::is_EOF($error_code);
Due to possible variants in conditions matching EOF, the use of this function is recommended for checking error codes against this value, rather than just using APR::Const::EOF directly.
APR::Const::EOF
is_ECONNABORTED
Check if the error is matching ECONNABORTED and its variants (corresponds to the APR_STATUS_IS_ECONNABORTED macro).
ECONNABORTED
APR_STATUS_IS_ECONNABORTED
$status = APR::Status::is_ECONNABORTED($error_code);
Due to possible variants in conditions matching ECONNABORTED, the use of this function is recommended for checking error codes against this value, rather than just using APR::Const::ECONNABORTED directly.
APR::Const::ECONNABORTED
is_ECONNRESET
Check if the error is matching ECONNRESET and its variants (corresponds to the APR_STATUS_IS_ECONNRESET macro).
ECONNRESET
APR_STATUS_IS_ECONNRESET
$status = APR::Status::is_ECONNRESET($error_code);
Due to possible variants in conditions matching ECONNRESET, the use of this function is recommended for checking error codes against this value, rather than just using APR::Const::ECONNRESET directly.
APR::Const::ECONNRESET
is_TIMEUP
Check if the error is matching TIMEUP and its variants (corresponds to the APR_STATUS_IS_TIMEUP macro).
TIMEUP
APR_STATUS_IS_TIMEUP
$status = APR::Status::is_TIMEUP($error_code);
Due to possible variants in conditions matching TIMEUP, the use of this function is recommended for checking error codes against this value, rather than just using APR::Const::TIMEUP directly.
APR::Const::TIMEUP
mod_perl 2.0 documentation.
mod_perl 2.0 and its core modules are copyrighted under The Apache Software License, Version 2.0.
The mod_perl development team and numerous contributors.
To install mod_perl2, copy and paste the appropriate command in to your terminal.
cpanm
cpanm mod_perl2
CPAN shell
perl -MCPAN -e shell install mod_perl2
For more information on module installation, please visit the detailed CPAN module installation guide.