* The build hooks used to implement distributed builds can now be run

in parallel.  Hooks are more efficient: locks on output paths are
  only acquired when the hook says that it is willing to accept a
  build job.  Hooks now work in two phases.  First, they should first
  tell Nix whether they are willing to accept a job.  Nix guarantuees
  that no two hooks will ever be in the first phase at the same time
  (this simplifies the implementation of hooks, since they don't have
  to perform locking (?)).  Second, if they accept a job, they are
  then responsible for building it (on the remote system), and copying
  the result back.  These can be run in parallel with other hooks and
  locally executed jobs.

  The implementation is a bit messy right now, though.  

* The directory `distributed' shows a (hacky) example of a hook that
  distributes build jobs over a set of machines listed in a
  configuration file.
This commit is contained in:
Eelco Dolstra 2004-05-13 19:14:49 +00:00
parent 5087c8f645
commit a8306cb98f
9 changed files with 502 additions and 148 deletions

119
distributed/build-remote.pl Executable file
View file

@ -0,0 +1,119 @@
#! /usr/bin/perl -w
use strict;
my $amWilling = shift @ARGV;
my $localSystem = shift @ARGV;
my $neededSystem = shift @ARGV;
my $storeExpr = shift @ARGV;
# Decline if the local system can do the build.
if ($amWilling && ($localSystem eq $neededSystem)) {
print "decline\n";
exit 0;
}
# Otherwise find a willing remote machine.
my %machines;
my %systemTypes;
my %sshKeys;
my %maxJobs;
my %curJobs;
# Read the list of machines.
open CONF, "< /home/eelco/nix/distributed/remote-systems.conf" or die;
while (<CONF>) {
chomp;
next if /^\s*$/;
/^\s*(\S+)\s+(\S+)\s+(\S+)\s+(\d+)\s*$/ or die;
$machines{$1} = "";
$systemTypes{$1} = $2;
$sshKeys{$1} = $3;
$maxJobs{$1} = $4;
}
close CONF;
# Read the current load status.
open LOAD, "< /home/eelco/nix/distributed/current-load" or die;
while (<LOAD>) {
chomp;
next if /^\s*$/;
/^\s*(\S+)\s+(\d+)\s*$/ or die;
$curJobs{$1} = $2;
}
close LOAD;
sub sendReply {
my $reply = shift;
open OUT, ">&3" or die;
print OUT "$reply\n";
close OUT;
}
# Find a suitable system.
my $rightType = 0;
my $machine;
foreach my $cur (keys %machines) {
if ($neededSystem eq $systemTypes{$cur}) {
$rightType = 1;
if (!defined $curJobs{$cur} or
($curJobs{$cur} < $maxJobs{$cur}))
{
$machine = $cur;
last;
}
}
}
if (!defined $machine) {
if ($rightType) {
sendReply "postpone";
exit 0;
} else {
sendReply "decline";
exit 0;
}
}
sendReply "accept";
open IN, "<&4" or die;
my $x = <IN>;
chomp $x;
print "got $x\n";
close IN;
print "BUILDING REMOTE: $storeExpr on $machine\n";
my $ssh = "ssh -i $sshKeys{$machine} -x";
my $inputs = `cat inputs`;
$inputs =~ s/\n/ /g;
my $outputs = `cat outputs`;
$outputs =~ s/\n/ /g;
my $successors = `cat successors`;
$successors =~ s/\n/ /g;
system "rsync -a -e '$ssh' $storeExpr $inputs $machine:/nix/store";
die "cannot rsync inputs to $machine" if ($? != 0);
system "$ssh $machine /nix/bin/nix-store --validpath $storeExpr $inputs";
die "cannot set valid paths on $machine" if ($? != 0);
system "$ssh $machine /nix/bin/nix-store --successor $successors";
die "cannot set successors on $machine" if ($? != 0);
print "BUILDING...\n";
system "$ssh $machine /nix/bin/nix-store -qnfvvvv $storeExpr";
die "remote build on $machine failed" if ($? != 0);
print "REMOTE BUILD DONE\n";
foreach my $output (split '\n', $outputs) {
system "rsync -a -e '$ssh' $machine:$output /nix/store";
die "cannot rsync outputs from $machine" if ($? != 0);
}

View file

@ -0,0 +1,2 @@
scratchy.labs.cs.uu.nl i686-linux /home/eelco/.ssh/id_scratchy_auto 2
mckroket.labs.cs.uu.nl powerpc-mac /home/eelco/.ssh/id_scratchy_mckroket 1

9
distributed/test.sh Executable file
View file

@ -0,0 +1,9 @@
#! /bin/sh
set -e
storeExpr=$(nix-instantiate ~/nixpkgs/pkgs/system/test.nix)
export NIX_BUILD_HOOK="build-remote.pl"
../src/nix-store/nix-store -qnvvvv -j0 $storeExpr

View file

@ -82,6 +82,12 @@ static void initAndRun(int argc, char * * argv)
if (sigaction(SIGINT, &act, &oact)) if (sigaction(SIGINT, &act, &oact))
throw SysError("installing handler for SIGINT"); throw SysError("installing handler for SIGINT");
/* Ignore SIGPIPE. */
act.sa_handler = SIG_IGN;
act.sa_flags = 0;
if (sigaction(SIGPIPE, &act, &oact))
throw SysError("ignoring SIGPIPE");
/* Process the NIX_LOG_TYPE environment variable. */ /* Process the NIX_LOG_TYPE environment variable. */
string lt = getEnv("NIX_LOG_TYPE"); string lt = getEnv("NIX_LOG_TYPE");
if (lt != "") setLogType(lt); if (lt != "") setLogType(lt);

View file

@ -17,6 +17,61 @@
static string pathNullDevice = "/dev/null"; static string pathNullDevice = "/dev/null";
struct Pipe
{
int readSide, writeSide;
Pipe();
~Pipe();
void create();
void closeReadSide();
void closeWriteSide();
};
Pipe::Pipe()
: readSide(0), writeSide(0)
{
}
Pipe::~Pipe()
{
closeReadSide();
closeWriteSide();
}
void Pipe::create()
{
int fds[2];
if (pipe(fds) != 0) throw SysError("creating pipe");
readSide = fds[0];
writeSide = fds[1];
}
void Pipe::closeReadSide()
{
if (readSide != 0) {
if (close(readSide) == -1)
printMsg(lvlError, format("cannot close read side of pipe"));
readSide = 0;
}
}
void Pipe::closeWriteSide()
{
if (writeSide != 0) {
if (close(writeSide) == -1)
printMsg(lvlError, format("cannot close write side of pipe"));
writeSide = 0;
}
}
/* A goal is a store expression that still has to be normalised. */ /* A goal is a store expression that still has to be normalised. */
struct Goal struct Goal
{ {
@ -55,7 +110,15 @@ struct Goal
int fdLogFile; int fdLogFile;
/* Pipe for the builder's standard output/error. */ /* Pipe for the builder's standard output/error. */
int fdsLogger[2]; Pipe logPipe;
/* Pipes for talking to the build hook (if any). */
Pipe toHook;
Pipe fromHook;
/* !!! clean up */
PathSet fnord;
map<Path, Path> xyzzy;
Goal(); Goal();
~Goal(); ~Goal();
@ -69,8 +132,6 @@ Goal::Goal()
, tmpDir("") , tmpDir("")
, fdLogFile(0) , fdLogFile(0)
{ {
fdsLogger[0] = 0;
fdsLogger[1] = 0;
} }
@ -100,10 +161,6 @@ Goal::~Goal()
if (fdLogFile && (close(fdLogFile) != 0)) if (fdLogFile && (close(fdLogFile) != 0))
printMsg(lvlError, format("cannot close fd")); printMsg(lvlError, format("cannot close fd"));
if (fdsLogger[0] && close(fdsLogger[0]) != 0)
printMsg(lvlError, format("cannot close fd"));
if (fdsLogger[1] && close(fdsLogger[1]) != 0)
printMsg(lvlError, format("cannot close fd"));
try { try {
deleteTmpDir(false); deleteTmpDir(false);
@ -164,15 +221,34 @@ public:
void run(); void run();
private: private:
bool canBuildMore();
/* Start building a derivation. Returns false if we decline to /* Start building a derivation. Returns false if we decline to
build it right now. */ build it right now. */
bool startBuild(Path nePath); bool startBuild(Path nePath);
/* Acquires locks on the output paths and gathers information
about the build (e.g., the input closures). During this
process its possible that we find out that the build is
unnecessary, in which case we return false (this is not an
error condition!). */
bool prepareBuild(Goal & goal);
void startBuildChild(Goal & goal); void startBuildChild(Goal & goal);
bool tryBuildHook(Goal & goal);
void openLogFile(Goal & goal);
void initChild(Goal & goal);
void childStarted(Goal & goal, pid_t pid);
/* Read from the logger pipes, and watch for child termination as /* Read from the logger pipes, and watch for child termination as
a side effect. */ a side effect. Return true when a child terminates, false
void wait(); otherwise. */
bool waitForChildren();
/* Wait for child processes to finish building a derivation. */ /* Wait for child processes to finish building a derivation. */
void reapChild(Goal & goal); void reapChild(Goal & goal);
@ -256,7 +332,7 @@ void Normaliser::run()
while (!goals.empty()) { while (!goals.empty()) {
printMsg(lvlVomit, "loop"); printMsg(lvlVomit, "main loop");
/* Start building as many buildable goals as possible. */ /* Start building as many buildable goals as possible. */
bool madeProgress = false; bool madeProgress = false;
@ -269,24 +345,30 @@ void Normaliser::run()
buildable.erase(*i); buildable.erase(*i);
} }
/* Wait until any child finishes (which may allow us to build
new goals). */
if (building.empty()) if (building.empty())
assert(madeProgress); /* shouldn't happen */ assert(madeProgress); /* shouldn't happen */
else else
wait(); do {
printMsg(lvlVomit, "waiting for children");
} while (!waitForChildren());
} }
assert(buildable.empty() && building.empty()); assert(buildable.empty() && building.empty());
} }
bool Normaliser::canBuildMore()
{
return building.size() < maxBuildJobs;
}
bool Normaliser::startBuild(Path nePath) bool Normaliser::startBuild(Path nePath)
{ {
checkInterrupt(); checkInterrupt();
if (maxBuildJobs > 0 && building.size() >= maxBuildJobs)
return false;
Goals::iterator goalIt = goals.find(nePath); Goals::iterator goalIt = goals.find(nePath);
assert(goalIt != goals.end()); assert(goalIt != goals.end());
Goal & goal(goalIt->second); Goal & goal(goalIt->second);
@ -295,6 +377,27 @@ bool Normaliser::startBuild(Path nePath)
startNest(nest, lvlTalkative, startNest(nest, lvlTalkative,
format("starting normalisation of goal `%1%'") % nePath); format("starting normalisation of goal `%1%'") % nePath);
/* Is the build hook willing to accept this job? */
if (tryBuildHook(goal)) return true;
if (!canBuildMore()) {
debug("postponing build");
return false;
}
/* Prepare the build, i.e., acquire locks and gather necessary
information. */
if (!prepareBuild(goal)) return true;
/* Otherwise, start the build in a child process. */
startBuildChild(goal);
return true;
}
bool Normaliser::prepareBuild(Goal & goal)
{
/* The outputs are referenceable paths. */ /* The outputs are referenceable paths. */
for (PathSet::iterator i = goal.expr.derivation.outputs.begin(); for (PathSet::iterator i = goal.expr.derivation.outputs.begin();
i != goal.expr.derivation.outputs.end(); ++i) i != goal.expr.derivation.outputs.end(); ++i)
@ -317,25 +420,23 @@ bool Normaliser::startBuild(Path nePath)
process can build this expression, so no further checks are process can build this expression, so no further checks are
necessary. */ necessary. */
Path nfPath; Path nfPath;
if (querySuccessor(nePath, nfPath)) { if (querySuccessor(goal.nePath, nfPath)) {
debug(format("skipping build of expression `%1%', someone beat us to it") debug(format("skipping build of expression `%1%', someone beat us to it")
% nePath); % goal.nePath);
goal.outputLocks.setDeletion(true); goal.outputLocks.setDeletion(true);
removeGoal(goal); removeGoal(goal);
return true; return false;
} }
/* Realise inputs (and remember all input paths). */ /* Realise inputs (and remember all input paths). */
PathSet fnord;
map<Path, Path> xyzzy;
for (PathSet::iterator i = goal.expr.derivation.inputs.begin(); for (PathSet::iterator i = goal.expr.derivation.inputs.begin();
i != goal.expr.derivation.inputs.end(); ++i) i != goal.expr.derivation.inputs.end(); ++i)
{ {
checkInterrupt(); checkInterrupt();
Path nfPath = useSuccessor(*i); Path nfPath = useSuccessor(*i);
realiseClosure(nfPath); realiseClosure(nfPath);
fnord.insert(nfPath); goal.fnord.insert(nfPath);
if (nfPath != *i) xyzzy[*i] = nfPath; if (nfPath != *i) goal.xyzzy[*i] = nfPath;
/* !!! nfPath should be a root of the garbage collector while /* !!! nfPath should be a root of the garbage collector while
we are building */ we are building */
StoreExpr ne = storeExprFromPath(nfPath); StoreExpr ne = storeExprFromPath(nfPath);
@ -348,7 +449,6 @@ bool Normaliser::startBuild(Path nePath)
} }
} }
/* We can skip running the builder if all output paths are already /* We can skip running the builder if all output paths are already
valid. */ valid. */
bool fastBuild = true; bool fastBuild = true;
@ -364,62 +464,9 @@ bool Normaliser::startBuild(Path nePath)
if (fastBuild) { if (fastBuild) {
printMsg(lvlChatty, format("skipping build; output paths already exist")); printMsg(lvlChatty, format("skipping build; output paths already exist"));
finishGoal(goal); finishGoal(goal);
return true; return false;
} }
/* !!! Hack */
Path buildHook = getEnv("NIX_BUILD_HOOK");
if (buildHook != "") {
printMsg(lvlChatty, format("using build hook `%1%'") % buildHook);
Path hookTmpDir = createTempDir();
Path inputListFN = hookTmpDir + "/inputs";
Path outputListFN = hookTmpDir + "/outputs";
Path successorsListFN = hookTmpDir + "/successors";
string s;
for (ClosureElems::iterator i = goal.inClosures.begin();
i != goal.inClosures.end(); ++i)
s += i->first + "\n";
for (PathSet::iterator i = fnord.begin();
i != fnord.end(); ++i)
s += *i + "\n";
writeStringToFile(inputListFN, s);
s = "";
for (PathSet::iterator i = goal.expr.derivation.outputs.begin();
i != goal.expr.derivation.outputs.end(); ++i)
s += *i + "\n";
writeStringToFile(outputListFN, s);
s = "";
for (map<Path, Path>::iterator i = xyzzy.begin();
i != xyzzy.end(); ++i)
s += i->first + " " + i->second + "\n";
writeStringToFile(successorsListFN, s);
int status = system((format("%1% %2% %3% %4% %5% %6% 1>&2")
% buildHook % goal.nePath % inputListFN % outputListFN
% successorsListFN
% goal.expr.derivation.platform).str().c_str());
if (WIFEXITED(status)) {
int code = WEXITSTATUS(status);
if (code == 100) { /* == accepted */
printMsg(lvlChatty,
format("build hook succesfully realised output paths"));
finishGoal(goal);
return true;
} else if (code != 101) /* != declined */
throw Error(
format("build hook returned exit code %1%") % code);
} else throw Error(
format("build hook died with status %1%") % status);
}
/* Otherwise, start the build in a child process. */
startBuildChild(goal);
return true; return true;
} }
@ -488,23 +535,15 @@ void Normaliser::startBuildChild(Goal & goal)
printMsg(lvlChatty, format("executing builder `%1%'") % printMsg(lvlChatty, format("executing builder `%1%'") %
goal.expr.derivation.builder); goal.expr.derivation.builder);
/* Create a log file. */ /* Create the log file and pipe. */
Path logFileName = nixLogDir + "/" + baseNameOf(goal.nePath); openLogFile(goal);
int fdLogFile = open(logFileName.c_str(),
O_CREAT | O_WRONLY | O_TRUNC, 0666);
if (fdLogFile == -1)
throw SysError(format("creating log file `%1%'") % logFileName);
goal.fdLogFile = fdLogFile;
/* Create a pipe to get the output of the child. */
if (pipe(goal.fdsLogger) != 0)
throw SysError("creating logger pipe");
/* Fork a child to build the package. Note that while we /* Fork a child to build the package. Note that while we
currently use forks to run and wait for the children, it currently use forks to run and wait for the children, it
shouldn't be hard to use threads for this on systems where shouldn't be hard to use threads for this on systems where
fork() is unavailable or inefficient. */ fork() is unavailable or inefficient. */
switch (goal.pid = fork()) { pid_t pid;
switch (pid = fork()) {
case -1: case -1:
throw SysError("unable to fork"); throw SysError("unable to fork");
@ -516,13 +555,7 @@ void Normaliser::startBuildChild(Goal & goal)
try { /* child */ try { /* child */
/* Put the child in a separate process group so that it initChild(goal);
doesn't receive terminal signals. */
if (setpgrp() == -1)
throw SysError(format("setting process group"));
if (chdir(goal.tmpDir.c_str()) == -1)
throw SysError(format("changing into to `%1%'") % goal.tmpDir);
/* Fill in the arguments. */ /* Fill in the arguments. */
Strings & args(goal.expr.derivation.args); Strings & args(goal.expr.derivation.args);
@ -545,10 +578,185 @@ void Normaliser::startBuildChild(Goal & goal)
i->first + "=" + i->second)->c_str(); i->first + "=" + i->second)->c_str();
*p = 0; *p = 0;
/* Execute the program. This should not return. */
execve(goal.expr.derivation.builder.c_str(),
(char * *) argArr, (char * *) envArr);
throw SysError(format("executing `%1%'")
% goal.expr.derivation.builder);
} catch (exception & e) {
cerr << format("build error: %1%\n") % e.what();
}
_exit(1);
}
/* parent */
childStarted(goal, pid);
}
string readLine(int fd)
{
string s;
while (1) {
char ch;
int rd = read(fd, &ch, 1);
if (rd == -1) {
if (errno != EINTR)
throw SysError("reading a line");
} else if (rd == 0)
throw Error("unexpected EOF reading a line");
else {
if (ch == '\n') return s;
s += ch;
}
}
}
bool Normaliser::tryBuildHook(Goal & goal)
{
Path buildHook = getEnv("NIX_BUILD_HOOK");
if (buildHook == "") return false;
buildHook = absPath(buildHook);
/* Create a directory where we will store files used for
communication between us and the build hook. */
goal.tmpDir = createTempDir();
/* Create the log file and pipe. */
openLogFile(goal);
/* Create the communication pipes. */
goal.toHook.create();
goal.fromHook.create();
/* Fork the hook. */
pid_t pid;
switch (pid = fork()) {
case -1:
throw SysError("unable to fork");
case 0:
try { /* child */
initChild(goal);
execl(buildHook.c_str(), buildHook.c_str(),
(canBuildMore() ? (string) "1" : "0").c_str(),
thisSystem.c_str(),
goal.expr.derivation.platform.c_str(),
goal.nePath.c_str());
throw SysError(format("executing `%1%'") % buildHook);
} catch (exception & e) {
cerr << format("build error: %1%\n") % e.what();
}
_exit(1);
}
/* parent */
childStarted(goal, pid);
goal.fromHook.closeWriteSide();
goal.toHook.closeReadSide();
/* Read the first line of input, which should be a word indicating
whether the hook wishes to perform the build. !!! potential
for deadlock here: we should also read from the child's logger
pipe. */
string reply = readLine(goal.fromHook.readSide);
debug(format("hook reply is `%1%'") % reply);
if (reply == "decline" || reply == "postpone") {
/* Clean up the child. !!! hacky / should verify */
/* !!! drain stdout of hook, wait for child process */
goal.pid = 0;
goal.fromHook.closeReadSide();
goal.toHook.closeWriteSide();
close(goal.fdLogFile);
goal.fdLogFile = 0;
goal.logPipe.closeReadSide();
building.erase(pid);
return reply == "postpone";
}
else if (reply == "accept") {
if (!prepareBuild(goal))
throw Error("NOT IMPLEMENTED: hook unnecessary");
Path inputListFN = goal.tmpDir + "/inputs";
Path outputListFN = goal.tmpDir + "/outputs";
Path successorsListFN = goal.tmpDir + "/successors";
string s;
for (ClosureElems::iterator i = goal.inClosures.begin();
i != goal.inClosures.end(); ++i)
s += i->first + "\n";
for (PathSet::iterator i = goal.fnord.begin();
i != goal.fnord.end(); ++i)
s += *i + "\n";
writeStringToFile(inputListFN, s);
s = "";
for (PathSet::iterator i = goal.expr.derivation.outputs.begin();
i != goal.expr.derivation.outputs.end(); ++i)
s += *i + "\n";
writeStringToFile(outputListFN, s);
s = "";
for (map<Path, Path>::iterator i = goal.xyzzy.begin();
i != goal.xyzzy.end(); ++i)
s += i->first + " " + i->second + "\n";
writeStringToFile(successorsListFN, s);
string okay = "okay\n";
writeFull(goal.toHook.writeSide,
(const unsigned char *) okay.c_str(), okay.size());
return true;
}
else throw Error(format("bad hook reply `%1%'") % reply);
}
void Normaliser::openLogFile(Goal & goal)
{
/* Create a log file. */
Path logFileName = nixLogDir + "/" + baseNameOf(goal.nePath);
int fdLogFile = open(logFileName.c_str(),
O_CREAT | O_WRONLY | O_TRUNC, 0666);
if (fdLogFile == -1)
throw SysError(format("creating log file `%1%'") % logFileName);
goal.fdLogFile = fdLogFile;
/* Create a pipe to get the output of the child. */
goal.logPipe.create();
}
void Normaliser::initChild(Goal & goal)
{
/* Put the child in a separate process group so that it doesn't
receive terminal signals. */
if (setpgrp() == -1)
throw SysError(format("setting process group"));
if (chdir(goal.tmpDir.c_str()) == -1)
throw SysError(format("changing into to `%1%'") % goal.tmpDir);
/* Dup the write side of the logger pipe into stderr. */ /* Dup the write side of the logger pipe into stderr. */
if (dup2(goal.fdsLogger[1], STDERR_FILENO) == -1) if (dup2(goal.logPipe.writeSide, STDERR_FILENO) == -1)
throw SysError("cannot pipe standard error into log file"); throw SysError("cannot pipe standard error into log file");
if (close(goal.fdsLogger[0]) != 0) /* close read side */ if (close(goal.logPipe.readSide) != 0) /* close read side */
throw SysError("closing fd"); throw SysError("closing fd");
/* Dup stderr to stdin. */ /* Dup stderr to stdin. */
@ -562,43 +770,45 @@ void Normaliser::startBuildChild(Goal & goal)
if (dup2(fdDevNull, STDIN_FILENO) == -1) if (dup2(fdDevNull, STDIN_FILENO) == -1)
throw SysError("cannot dup null device into stdin"); throw SysError("cannot dup null device into stdin");
/* When running a hook, dup the communication pipes. */
bool inHook = goal.fromHook.writeSide != 0;
if (inHook) {
goal.fromHook.closeReadSide();
if (dup2(goal.fromHook.writeSide, 3) == -1)
throw SysError("dup");
goal.toHook.closeWriteSide();
if (dup2(goal.toHook.readSide, 4) == -1)
throw SysError("dup");
}
/* Close all other file descriptors. */ /* Close all other file descriptors. */
int maxFD = 0; int maxFD = 0;
maxFD = sysconf(_SC_OPEN_MAX); maxFD = sysconf(_SC_OPEN_MAX);
debug(format("closing fds up to %1%") % (int) maxFD);
for (int fd = 0; fd < maxFD; ++fd) for (int fd = 0; fd < maxFD; ++fd)
if (fd != STDIN_FILENO && fd != STDOUT_FILENO && fd != STDERR_FILENO) if (fd != STDIN_FILENO && fd != STDOUT_FILENO && fd != STDERR_FILENO
&& (!inHook || (fd != 3 && fd != 4)))
close(fd); /* ignore result */ close(fd); /* ignore result */
/* Execute the program. This should not return. */
execve(goal.expr.derivation.builder.c_str(),
(char * *) argArr, (char * *) envArr);
throw SysError(format("unable to execute %1%")
% goal.expr.derivation.builder);
} catch (exception & e) {
cerr << format("build error: %1%\n") % e.what();
}
_exit(1);
} }
/* parent */
void Normaliser::childStarted(Goal & goal, pid_t pid)
{
goal.pid = pid;
building[goal.pid] = goal.nePath; building[goal.pid] = goal.nePath;
/* Close the write side of the logger pipe. */ /* Close the write side of the logger pipe. */
if (close(goal.fdsLogger[1]) != 0) goal.logPipe.closeWriteSide();
throw SysError("closing fd");
goal.fdsLogger[1] = 0;
} }
void Normaliser::wait() bool Normaliser::waitForChildren()
{ {
checkInterrupt(); checkInterrupt();
bool terminated = false;
/* Process log output from the children. We also use this to /* Process log output from the children. We also use this to
detect child termination: if we get EOF on the logger pipe of a detect child termination: if we get EOF on the logger pipe of a
build, we assume that the builder has terminated. */ build, we assume that the builder has terminated. */
@ -613,13 +823,13 @@ void Normaliser::wait()
i != building.end(); ++i) i != building.end(); ++i)
{ {
Goal & goal(goals[i->second]); Goal & goal(goals[i->second]);
int fd = goal.fdsLogger[0]; int fd = goal.logPipe.readSide;
FD_SET(fd, &fds); FD_SET(fd, &fds);
if (fd >= fdMax) fdMax = fd + 1; if (fd >= fdMax) fdMax = fd + 1;
} }
if (select(fdMax, &fds, 0, 0, 0) == -1) { if (select(fdMax, &fds, 0, 0, 0) == -1) {
if (errno == EINTR) return; if (errno == EINTR) return false;
throw SysError("waiting for input"); throw SysError("waiting for input");
} }
@ -629,7 +839,7 @@ void Normaliser::wait()
{ {
checkInterrupt(); checkInterrupt();
Goal & goal(goals[i->second]); Goal & goal(goals[i->second]);
int fd = goal.fdsLogger[0]; int fd = goal.logPipe.readSide;
if (FD_ISSET(fd, &fds)) { if (FD_ISSET(fd, &fds)) {
unsigned char buffer[1024]; unsigned char buffer[1024];
ssize_t rd = read(fd, buffer, sizeof(buffer)); ssize_t rd = read(fd, buffer, sizeof(buffer));
@ -640,6 +850,7 @@ void Normaliser::wait()
} else if (rd == 0) { } else if (rd == 0) {
debug(format("EOF on `%1%'") % goal.nePath); debug(format("EOF on `%1%'") % goal.nePath);
reapChild(goal); reapChild(goal);
terminated = true;
} else { } else {
printMsg(lvlVomit, format("read %1% bytes from `%2%'") printMsg(lvlVomit, format("read %1% bytes from `%2%'")
% rd % goal.nePath); % rd % goal.nePath);
@ -649,6 +860,8 @@ void Normaliser::wait()
} }
} }
} }
return terminated;
} }
@ -660,7 +873,8 @@ void Normaliser::reapChild(Goal & goal)
to have terminated. In fact, the builder could also have to have terminated. In fact, the builder could also have
simply have closed its end of the pipe --- just don't do that simply have closed its end of the pipe --- just don't do that
:-) */ :-) */
if (waitpid(goal.pid, &status, WNOHANG) != goal.pid) /* !!! this could block! */
if (waitpid(goal.pid, &status, 0) != goal.pid)
throw SysError(format("builder for `%1%' should have terminated") throw SysError(format("builder for `%1%' should have terminated")
% goal.nePath); % goal.nePath);
@ -669,9 +883,7 @@ void Normaliser::reapChild(Goal & goal)
goal.pid = 0; goal.pid = 0;
/* Close the read side of the logger pipe. */ /* Close the read side of the logger pipe. */
if (close(goal.fdsLogger[0]) != 0) goal.logPipe.closeReadSide();
throw SysError("closing fd");
goal.fdsLogger[0] = 0;
/* Close the log file. */ /* Close the log file. */
if (close(goal.fdLogFile) != 0) if (close(goal.fdLogFile) != 0)

View file

@ -18,8 +18,10 @@ locking.sh: locking.nix
parallel.sh: parallel.nix parallel.sh: parallel.nix
build-hook.sh: build-hook.nix build-hook.sh: build-hook.nix
TESTS = init.sh simple.sh dependencies.sh locking.sh parallel.sh \ TESTS = init.sh build-hook.sh
build-hook.sh
#TESTS = init.sh simple.sh dependencies.sh locking.sh parallel.sh \
# build-hook.sh
XFAIL_TESTS = XFAIL_TESTS =

View file

@ -1,17 +1,21 @@
#! /bin/sh
set -x set -x
drv=$1 drv=$4
echo "HOOK for $drv" echo "HOOK for $drv" >&2
outPath=$(sed 's/Derive(\[\"\([^\"]*\)\".*/\1/' $drv) outPath=$(sed 's/Derive(\[\"\([^\"]*\)\".*/\1/' $drv)
echo "output path is $outPath" echo "output path is $outPath" >&2
if $(echo $outPath | grep -q input-1); then if $(echo $outPath | grep -q input-1); then
echo "accept" >&3
read x <&4
echo "got $x"
mkdir $outPath mkdir $outPath
echo "BAR" > $outPath/foo echo "BAR" > $outPath/foo
exit 100 else
echo "decline" >&3
fi fi
exit 101

View file

@ -1,4 +1,4 @@
export NIX_BUILD_HOOK="sh build-hook.hook.sh" export NIX_BUILD_HOOK="build-hook.hook.sh"
storeExpr=$($TOP/src/nix-instantiate/nix-instantiate build-hook.nix) storeExpr=$($TOP/src/nix-instantiate/nix-instantiate build-hook.nix)

View file

@ -2,7 +2,7 @@ storeExpr=$($TOP/src/nix-instantiate/nix-instantiate parallel.nix)
echo "store expr is $storeExpr" echo "store expr is $storeExpr"
outPath=$($TOP/src/nix-store/nix-store -qnfvvvv -j0 "$storeExpr") outPath=$($TOP/src/nix-store/nix-store -qnfvvvv -j10000 "$storeExpr")
echo "output path is $outPath" echo "output path is $outPath"