#
# Dev-Editor - Module File::Access
#
-# Some simple routines for doing things with files
-# with only one command
+# Some simple routines for doing things with files by
+# using only one command
#
-# Author: Patrick Canterino <patshaping@gmx.net>
-# Last modified: 2003-10-13
+# Author: Patrick Canterino <patrick@patshaping.de>
+# Last modified: 2004-12-17
#
use strict;
-use vars qw(@EXPORT);
+use vars qw(@EXPORT
+ $has_flock);
-use Carp qw(croak);
+use Fcntl qw(:DEFAULT
+ :flock);
### Export ###
@EXPORT = qw(dir_read
file_create
+ file_lock
file_read
- file_save);
+ file_save
+ file_unlock
+
+ LOCK_SH
+ LOCK_EX
+ LOCK_UN
+ LOCK_NB);
+
+# Check if flock() is available
+# I found this piece of code somewhere in the internet
+
+$has_flock = eval { local $SIG{'__DIE__'}; flock(STDOUT,0); 1 };
# dir_read()
#
# Sort the entries
- @entries = sort(@entries);
+ @entries = sort {uc($a) cmp uc($b)} @entries;
my @files;
my @dirs;
# file_create()
#
-# Create a file
+# Create a file, but only if it doesn't already exist
+#
+# (I wanted to use O_EXCL for this, but `perldoc -f sysopen`
+# doesn't say that it is available on every system - so I
+# created this workaround using O_RDONLY and O_CREAT)
#
# Params: File to create
#
return if(-e $file);
- open(FILE,">",$file) or return;
- close(FILE) or return;
+ sysopen(FILE,$file,O_RDONLY | O_CREAT) or return;
+ close(FILE) or return;
return 1;
}
+# file_lock()
+#
+# System independent wrapper function for flock()
+# On systems where flock() is not available, this function
+# always returns true.
+#
+# Params: 1. Filehandle
+# 2. Locking mode
+#
+# Return: Status code (Boolean)
+
+sub file_lock(*$)
+{
+ my ($handle,$mode) = @_;
+
+ return 1 unless($has_flock);
+ return flock($handle,$mode);
+}
+
# file_read()
#
# Read out a file completely
my $file = shift;
local *FILE;
- open(FILE,"<",$file) or return;
+ sysopen(FILE,$file,O_RDONLY) or return;
+ file_lock(FILE,LOCK_SH) or do { close(FILE); return };
+
read(FILE, my $content, -s $file);
- close(FILE) or return;
+
+ file_lock(FILE,LOCK_UN) or do { close(FILE); return };
+ close(FILE) or return;
return \$content;
}
#
# Params: 1. File
# 2. File content as Scalar Reference
+# 3. true => open in binary mode
+# false => open in normal mode (default)
#
# Return: Status code (Boolean)
-sub file_save($$)
+sub file_save($$;$)
{
- my ($file,$content) = @_;
- my $temp = $file.".temp";
+ my ($file,$content,$binary) = @_;
local *FILE;
- open(FILE,">",$temp) or return;
- print FILE $$content or do { close(FILE); return };
- close(FILE) or return;
+ sysopen(FILE,$file,O_WRONLY | O_CREAT | O_TRUNC) or return;
+ file_lock(FILE,LOCK_EX) or do { close(FILE); return };
+ binmode(FILE) if($binary);
+
+ print FILE $$content or do { close(FILE); return };
- rename($temp,$file) or return;
+ file_lock(FILE,LOCK_UN) or do { close(FILE); return };
+ close(FILE) or return;
return 1;
}
+# file_unlock()
+#
+# Remove a file from the list of files in use
+#
+# Params: 1. File::UseList object
+# 2. File to remove
+#
+# Return: -nothing-
+
+sub file_unlock($$)
+{
+ my ($uselist,$file) = @_;
+
+ $uselist->remove_file($file);
+ $uselist->save;
+
+ return;
+}
+
# it's true, baby ;-)
1;