On Sun, Mar 17, 2013 at 08:15:32PM +0800, Daniel Hartwig wrote:
> On 17 March 2013 19:56, Serafeim Zanikolas <s...@debian.org> wrote:
> > On Sun, Mar 17, 2013 at 02:14:50PM +0800, Daniel Hartwig wrote:
> >> The data can be passed through an open fd, similar to dpkg --status-fd
> >> argument. Then there are no issues due to filesystems global
> >> namespace and it removes the fs as an unrequired middle-man.
> >
> > Sure, that'd be an improvement. Would you make apt pass the fd number to
> > apt-listbugs in the command line?
>
> or just using a well known env. variable that will also work with
> substituation in the command line.
Attached the updated patches for apt and apt-listbugs, which implement
Daniel's proposal of using an fd rather than a fifo.
The HookFifoFilename option is replaced by:
DPkgs::Tools::Options::/usr/sbin/apt-listbugs::HookAvoidStdin "yes";
The default value of Pipes[0] (the fd to be inherited and read by
apt-listbugs) was normally 3, which seems to be FD_CLOEXEC'd somewhere before
the exec to apt-listbugs (apt-listbugs was failing with EBADF), so I'm using
instead 20 as a minimum.
--
Every great idea is worthless without someone to do the work. --Neil Williams
diff --git a/apt-listbugs b/apt-listbugs
index 58d67cb..b387947 100755
--- a/apt-listbugs
+++ b/apt-listbugs
@@ -289,7 +289,19 @@ when "apt"
puts if $DEBUG
puts "Pre-Install-Pkgs hook info:" if $DEBUG
state=1
- STDIN.each { |pkg|
+ apt_hook_fd = ENV["AptHookFd"]
+ if apt_hook_fd.nil?
+ $stderr.puts sprintf(_("E: AptHookFd is undefined"))
+ exit(1)
+ end
+ begin
+ apt_hook_stream = IO.open(apt_hook_fd, 'r')
+ rescue Errno::ENOENT
+ $stderr.puts sprintf(_("W: Cannot open file descriptor %s"), apt_hook_fd)
+ exit(1)
+ end
+
+ apt_hook_stream.each { |pkg|
pkg=pkg.rstrip
case state
when 1
@@ -353,6 +365,7 @@ when "apt"
end
end
}
+ apt_hook_stream.close
puts if $DEBUG
when "list", "rss"
ARGV.each { |pkg|
diff --git a/apt-pkg/deb/dpkgpm.cc b/apt-pkg/deb/dpkgpm.cc
index 6cb8bc6..dabf48c 100644
--- a/apt-pkg/deb/dpkgpm.cc
+++ b/apt-pkg/deb/dpkgpm.cc
@@ -328,8 +328,9 @@ bool pkgDPkgPM::SendV2Pkgs(FILE *F)
// DPkgPM::RunScriptsWithPkgs - Run scripts with package names on stdin /*{{{*/
// ---------------------------------------------------------------------
/* This looks for a list of scripts to run from the configuration file
- each one is run and is fed on standard input a list of all .deb files
- that are due to be installed. */
+ each one is run and is fed on standard input (or another fd, if
+ HookAvoidStdin is set) a list of all .deb files that are due to be
+ installed. */
bool pkgDPkgPM::RunScriptsWithPkgs(const char *Cnf)
{
Configuration::Item const *Opts = _config->Tree(Cnf);
@@ -352,10 +353,14 @@ bool pkgDPkgPM::RunScriptsWithPkgs(const char *Cnf)
unsigned int Version = _config->FindI(OptSec+"::Version",1);
+ // Feed subprocess via stdin, unless HookAvoidStdin is true
+ bool const UseStdin = !_config->FindB(OptSec+"::HookAvoidStdin",false);
+
// Create the pipes
int Pipes[2];
if (pipe(Pipes) != 0)
return _error->Errno("pipe","Failed to create IPC pipe to subprocess");
+ if (UseStdin == true)
SetCloseExec(Pipes[0],true);
SetCloseExec(Pipes[1],true);
@@ -364,7 +369,21 @@ bool pkgDPkgPM::RunScriptsWithPkgs(const char *Cnf)
if (Process == 0)
{
// Setup the FDs
+ if (UseStdin == true)
dup2(Pipes[0],STDIN_FILENO);
+ else
+ {
+ // small fd numbers (<5) are closed down the process tree, so use
+ // a higher number instead
+ int ChildReadFd = fcntl(Pipes[0], F_DUPFD, 20);
+ if (ChildReadFd < 0)
+ return _error->Errno("fcntl","Failed to duplicate file descriptor");
+ char AptHookEnv[80];
+ if (sprintf(AptHookEnv, "AptHookFd=%d", ChildReadFd) < 0)
+ return _error->Errno("sprintf","Failed to contruct environment variable value");
+ if (putenv(AptHookEnv) != 0)
+ return _error->Errno("putenv","Failed to set environment variable AptHookFd");
+ }
SetCloseExec(STDOUT_FILENO,false);
SetCloseExec(STDIN_FILENO,false);
SetCloseExec(STDERR_FILENO,false);
