Commit graph

1860 commits

Author SHA1 Message Date
Eelco Dolstra def5160b61 Clear any immutable bits in the Nix store
Doing this once makes subsequent operations like garbage collecting
more efficient since we don't have to call makeMutable() first.
2013-01-03 12:59:23 +01:00
Eelco Dolstra 299141ecbd If a substitute closure is incomplete, build dependencies, then retry the substituter
Issue #77.
2013-01-02 12:38:28 +01:00
Eelco Dolstra 1b3a78a459 Automatically fall back if the references of a substitute are not substitutable
Fixes #77.
2013-01-02 12:00:26 +01:00
Eelco Dolstra 12f9129f60 nix-build: Support talking to old daemons
Fixes #76.
2012-12-29 23:21:46 +01:00
Eelco Dolstra b7629778ef Allow mounting a path in a different location in the chroot
Fixes #24.
2012-12-29 23:04:02 +01:00
Eelco Dolstra 2754a07ead nix-store -q --roots: Respect the gc-keep-outputs/gc-keep-derivations settings
So if a path is not garbage solely because it's reachable from a root
due to the gc-keep-outputs or gc-keep-derivations settings, ‘nix-store
-q --roots’ now shows that root.
2012-12-20 18:41:44 +01:00
Eelco Dolstra 06f62defe6 Yet another rewrite of the garbage collector
But this time it's *obviously* correct!  No more segfaults due to
infinite recursions for sure, etc.

Also, move directories to /nix/store/trash instead of renaming them to
/nix/store/bla-gc-<pid>.  Then we can just delete /nix/store/trash at
the end.
2012-12-20 17:32:15 +01:00
Eelco Dolstra e775d4d84f If gc-keep-derivations is set, only keep the actual deriver
This prevents zillions of derivations from being kept, and fixes an
infinite recursion in the garbage collector (due to an obscure cycle
that can occur with fixed-output derivations).
2012-12-19 15:33:09 +01:00
Eelco Dolstra fbf0b2fa45 Kill the build hook rather than shutting it down cleanly
Waiting for the hook to shut down cleanly sometimes seems to lead to
hangs.
2012-12-19 11:47:42 +01:00
Eelco Dolstra 228ea7c2f9 Revert brain fart
This reverts commit cc511fd65b.
2012-12-18 20:43:47 +01:00
Eelco Dolstra cc511fd65b Check for potential infinite select() loops when building 2012-12-18 18:50:05 +01:00
Stuart Pernsteiner a9045c727f fix use-after-free bug in mkString(Value&, Symbol&) 2012-12-13 11:13:20 +01:00
Eelco Dolstra 9fa12fc201 Allow setting the profile location using $NIX_PROFILE
Fixes #69.
2012-12-12 16:01:46 +01:00
Eelco Dolstra 772778c0ec On SQLITE_BUSY, wait a random amount of time
If all contending processes wait a fixed amount of time (100 ms),
there is a good probability that they'll just collide again.
2012-12-11 11:49:42 +01:00
Eelco Dolstra 3100b29fc5 Tiny optimisation in the filter primop 2012-12-04 17:22:20 +01:00
Eelco Dolstra 5ad89398d1 nix-env: Install all outputs of a derivation
If you explicitly install a package, presumably you want all of it.
So symlink all outputs in the user environment.
2012-12-04 14:20:36 +01:00
Eelco Dolstra d62fc71b85 Fix the ‘--prebuilt-only’ flag 2012-12-03 21:01:41 +01:00
Eelco Dolstra 4bb4d5479a Whitespace 2012-12-03 18:19:49 +01:00
Eelco Dolstra 8eed07cda4 nix-env -q --out-path: Support multiple outputs
We now print all output paths of a package, e.g.

  openssl-1.0.0i  bin=/nix/store/gq2mvh0wb9l90djvsagln3aqywqmr6vl-openssl-1.0.0i-bin;man=/nix/store/7zwf5r5hsdarl3n86dasvb4chm2xzw9n-openssl-1.0.0i-man;/nix/store/cj7xvk7fjp9q887359j75pw3pzjfmqf1-openssl-1.0.0i

or (in XML mode)

  <item attrPath="openssl" name="openssl-1.0.0i" system="x86_64-linux">
    <output name="bin" path="/nix/store/gq2mvh0wb9l90djvsagln3aqywqmr6vl-openssl-1.0.0i-bin" />
    <output name="man" path="/nix/store/7zwf5r5hsdarl3n86dasvb4chm2xzw9n-openssl-1.0.0i-man" />
    <output name="out" path="/nix/store/cj7xvk7fjp9q887359j75pw3pzjfmqf1-openssl-1.0.0i" />
  </item>
2012-11-28 13:49:44 +01:00
Eelco Dolstra 6c98e6a5de Optionally ignore null-valued derivation attributes
This allows adding attributes like

  attr = if stdenv.system == "bla" then something else null;

without changing the resulting derivation on non-<bla> platforms.

We once considered adding a special "ignore" value for this purpose,
but using null seems more elegant.
2012-11-27 15:01:32 +01:00
Eelco Dolstra 8b8ee53bc7 Add builtin constants ‘langVersion’ and ‘nixVersion’
The integer constant ‘langVersion’ denotes the current language
version.  It gets increased every time a language feature is
added/changed/removed.  It's currently 1.

The string constant ‘nixVersion’ contains the current Nix version,
e.g. "1.2pre2980_9de6bc5".
2012-11-27 13:29:55 +01:00
Eelco Dolstra 5943f41b8b queryMissing(): Handle partially valid derivations 2012-11-26 18:25:12 +01:00
Eelco Dolstra 408a7bfac1 nix-instantiate: Fix read-only evaluation 2012-11-26 17:41:10 +01:00
Eelco Dolstra 8d8d47abd2 Only substitute wanted outputs of a derivation
If a derivation has multiple outputs, then we only want to download
those outputs that are actuallty needed.  So if we do "nix-build -A
openssl.man", then only the "man" output should be downloaded.
Likewise if another package depends on ${openssl.man}.

The tricky part is that different derivations can depend on different
outputs of a given derivation, so we may need to restart the
corresponding derivation goal if that happens.
2012-11-26 17:15:09 +01:00
Eelco Dolstra 46a369ad95 Make "nix-build -A <derivation>.<output>" do the right thing
For example, given a derivation with outputs "out", "man" and "bin":

  $ nix-build -A pkg

produces ./result pointing to the "out" output;

  $ nix-build -A pkg.man

produces ./result-man pointing to the "man" output;

  $ nix-build -A pkg.all

produces ./result, ./result-man and ./result-bin;

  $ nix-build -A pkg.all -A pkg2

produces ./result, ./result-man, ./result-bin and ./result-2.
2012-11-26 15:39:10 +01:00
Eelco Dolstra 9de6bc5d05 nix-store -r: Add ‘--ignore-unknown’ flag
This flag causes paths that do not have a known substitute to be
quietly ignored.  This is mostly useful for Charon, allowing it to
speed up deployment by letting a machine use substitutes for all
substitutable paths, instead of uploading them.  The latter is
frequently faster, e.g. if the target machine has a fast Internet
connection while the source machine is on a slow ADSL line.
2012-11-20 00:27:25 +01:00
Eelco Dolstra bf3725da2a nix-store -r: Don't quietly ignore missing paths 2012-11-19 23:51:56 +01:00
Eelco Dolstra 17dc306aa3 Revert "prim_toPath: Actually make the string a path"
This reverts commit 2980d1fba9.  It
causes a regression in NixOS evaluation:

string `/nix/store/ya3s5gmj3b28170fpbjhgsk8wzymkpa1-pommed-1.39/etc/pommed.conf' cannot refer to other paths
2012-11-15 23:04:34 +01:00
Eelco Dolstra f794465ca8 Disable use of vfork()
vfork() is just too weird.  For instance, in this build:

  http://hydra.nixos.org/build/3330487

the value fromHook.writeSide becomes corrupted in the parent, even
though the child only reads from it.  At -O0 the problem goes away.
Probably the child is overriding some spilled temporary variable.

If I get bored I may implement using posix_spawn() instead.
2012-11-15 19:35:18 +01:00
Eelco Dolstra 8541d27fce Don't use std::cerr in a few places
Slightly scared of using std::cerr in a vforked process...
2012-11-15 15:01:02 +01:00
Eelco Dolstra 3acc8adcad Add some debug code 2012-11-15 13:55:02 +01:00
Eelco Dolstra ea89df2b76 Use vfork() instead of fork() if available
Hopefully this reduces the chance of hitting ‘unable to fork: Cannot
allocate memory’ errors.  vfork() is used for everything except
starting builders.
2012-11-09 18:00:33 +01:00
Eelco Dolstra 48c19c4633 Remove definition of non-existant function 2012-11-09 17:59:41 +01:00
Eelco Dolstra 198dbe7fa1 Remove some redundant close() calls
They are unnecessary because we set the close-on-exec flag.
2012-11-09 16:58:51 +01:00
Eelco Dolstra 10dcee99ed Remove the quickExit function 2012-11-09 16:42:10 +01:00
Eelco Dolstra 4c9e3fa641 Remove a Darwin hack that should no longer be needed 2012-11-09 16:35:42 +01:00
Eelco Dolstra 88164325fa Fix a segfault when auto-calling a "a@{...}" function
Since the called function can return its argument attribute set
(e.g. "a"), the latter should not be allocated on the stack.

Reported by Shea.
2012-11-09 15:09:31 +01:00
Eelco Dolstra f581ce0b0c Don't start copy-from-other-stores if $NIX_OTHER_STORES is unset
Slight optimisation.
2012-11-09 14:58:10 +01:00
Eelco Dolstra 91ef4d9a81 Remove unnecessary call to closeMostFDs()
We have close-on-exec on all FDs now, and there is no security risk in
passing open FDs to substituters anyway.
2012-11-09 14:43:47 +01:00
Shea Levy d0fc615af6 canonicalizePathMetaData: Fall-back to utimes if lutimes fails due to ENOSYS 2012-11-06 11:29:59 +01:00
Eelco Dolstra 4c34d384e6 If hashes do not match, print them in base-32 for SHA-1/SHA-256
Fixes #57.
2012-10-23 18:05:50 +02:00
Shea Levy 2980d1fba9 prim_toPath: Actually make the string a path 2012-10-23 16:39:35 +02:00
Eelco Dolstra e345182055 Shorten the names of temporary build directories 2012-10-11 14:03:06 -04:00
Eelco Dolstra 70f75be199 getDerivation(): Don't always quietly ignore assertion failure
Ignoring assertion failures makes some sense for nix-env -qa, but not
for nix-instantiate/nix-build or hydra-eval-jobs.
2012-10-04 15:22:25 -04:00
Eelco Dolstra ad328bea15 XML writer: flush after newlines
This is useful for hydra-eval-jobs.
2012-10-04 14:07:36 -04:00
Eelco Dolstra 904f50412c nix-store --verify: Continue on errors 2012-10-04 10:20:23 -04:00
Eelco Dolstra 90b8a34f82 Fix regular expression
http://hydra.nixos.org/build/3123177
2012-10-04 09:46:10 -04:00
Eelco Dolstra e35d6f78dc Rename nix-worker to nix-daemon 2012-10-03 17:59:23 -04:00
Eelco Dolstra 522ecab9b8 Drop support for running nix-worker in "slave" mode
AFAIK nobody uses this, setuid binaries are evil, and there is no good
reason why people can't just run the daemon.
2012-10-03 17:30:45 -04:00
Eelco Dolstra 7586095504 Remove bin2c 2012-10-03 16:59:28 -04:00
Eelco Dolstra a562d544d8 When ‘--help’ is given, just run ‘man’ to show the manual page
I.e. do what git does.  I'm too lazy to keep the builtin help text up
to date :-)

Also add ‘--help’ to various commands that lacked it
(e.g. nix-collect-garbage).
2012-10-03 16:40:09 -04:00
Eelco Dolstra 2bbc4a214e nix-env: Support ‘--repair’ flag 2012-10-03 15:35:42 -04:00
Eelco Dolstra 0a7084567f Add a ‘--repair’ flag to nix-instantiate
This allows repairing corrupted derivations and other source files.
2012-10-03 15:09:18 -04:00
Eelco Dolstra a807edfae8 Handle repairing paths that are in build-chroot-dirs 2012-10-03 11:20:16 -04:00
Eelco Dolstra a3f205b249 When repairing a derivation, check and repair the entire output closure
If we find a corrupted path in the output closure, we rebuild the
derivation that produced that particular path.
2012-10-03 10:38:09 -04:00
Eelco Dolstra 2001895f3d Add a --repair flag to ‘nix-store -r’ to repair derivation outputs
With this flag, if any valid derivation output is missing or corrupt,
it will be recreated by using a substitute if available, or by
rebuilding the derivation.  The latter may use hash rewriting if
chroots are not available.
2012-10-02 17:13:46 -04:00
Eelco Dolstra cf46f19444 nix-store -r: Get rid of an unnecessary call to buildPaths/ensurePaths 2012-10-02 16:00:09 -04:00
Eelco Dolstra 8e3a7bd712 nix-store --verify: Add an option ‘--repair’ to repair all missing/corrupt paths
Also, return a non-zero exit code if errors remain after
verifying/repairing.
2012-10-02 15:12:56 -04:00
Eelco Dolstra 9958bd6992 Add operation ‘nix-store --repair-path’
This operation allows fixing corrupted or accidentally deleted store
paths by redownloading them using substituters, if available.

Since the corrupted path cannot be replaced atomically, there is a
very small time window (one system call) during which neither the old
(corrupted) nor the new (repaired) contents are available.  So
repairing should be used with some care on critical packages like
Glibc.
2012-10-02 14:08:59 -04:00
Eelco Dolstra e666e1156f Handle octal escapes in /proc/self/mountinfo 2012-09-28 21:39:30 -04:00
Eelco Dolstra f406288cc7 Print a more descriptive error message if setting up the build environment fails 2012-09-28 21:37:02 -04:00
Eelco Dolstra 95c74eae26 Allow dashes in identifiers
In Nixpkgs, the attribute in all-packages.nix corresponding to a
package is usually equal to the package name.  However, this doesn't
work if the package contains a dash, which is fairly common.  The
convention is to replace the dash with an underscore (e.g. "dbus-lib"
becomes "dbus_glib"), but that's annoying.  So now dashes are valid in
variable / attribute names, allowing you to write:

  dbus-glib = callPackage ../development/libraries/dbus-glib { };

and

  buildInputs = [ dbus-glib ];

Since we don't have a negation or subtraction operation in Nix, this
is unambiguous.
2012-09-27 15:49:20 -04:00
Eelco Dolstra d534f137f0 Make the store writable before creating /nix/store/.links 2012-09-25 16:30:08 -04:00
Eelco Dolstra e464b0247d Merge branch 'readonly-store' 2012-09-25 15:38:00 -04:00
Eelco Dolstra 28bf183d2d Include <sys/types.h> for off_t
Reported by "gio" on IRC.
2012-09-25 13:00:19 -04:00
Eelco Dolstra b9c2b4d5b4 Remove setting of the immutable bit
Using the immutable bit is problematic, especially in conjunction with
store optimisation.  For instance, if the garbage collector deletes a
file, it has to clear its immutable bit, but if the file has
additional hard links, we can't set the bit afterwards because we
don't know the remaining paths.

So now that we support having the entire Nix store as a read-only
mount, we may as well drop the immutable bit.  Unfortunately, we have
to keep the code to clear the immutable bit for backwards
compatibility.
2012-09-19 16:17:54 -04:00
Eelco Dolstra b9124a5c33 Support having /nix/store as a read-only bind mount
It turns out that the immutable bit doesn't work all that well.  A
better way is to make the entire Nix store a read-only bind mount,
i.e. by doing

  $ mount --bind /nix/store /nix/store
  $ mount -o remount,ro,bind /nix/store

(This would typically done in an early boot script, before anything
from /nix/store is used.)

Since Nix needs to be able to write to the Nix store, it now detects
if /nix/store is a read-only bind mount and then makes it writable in
a private mount namespace.
2012-09-19 15:45:29 -04:00
Eelco Dolstra 76e88871b2 Templatise tokenizeString() 2012-09-19 15:43:23 -04:00
Eelco Dolstra 00092b2d35 Keep build directory if not all expected outputs were produced
Fixes issue #123 in Nixpkgs.
2012-09-18 10:11:42 -04:00
Eelco Dolstra 9fd9dedf12 nix-env --delete-generations: Support --dry-run flag
Fixes #43.
2012-09-13 18:05:04 -04:00
Eelco Dolstra 8fbe96cb31 RemoteStore::connectToDaemon(): Set close-on-exec flag
This ensures that "nix-build --run-env" doesn't keep a connection to
the worker open, preventing it from exiting.
2012-09-13 14:46:37 -04:00
Eelco Dolstra e6e495649c Vacuum the SQLite DB after running the garbage collector 2012-09-13 14:33:41 -04:00
Eelco Dolstra 2923b55f9d Delete paths in a component in topologically sorted order
The outputs of a derivation can refer to each other (even though they
cannot have cycles), so they have to be deleted in the right order.

http://hydra.nixos.org/build/3026118
2012-09-13 13:08:27 -04:00
Eelco Dolstra 6c4ac29917 Disable auto store optimisation for now
I've seen operations like "nix-store --import" take much longer on one
system.  So default to off until I've investigated this a bit further.
2012-09-13 10:28:20 -04:00
Eelco Dolstra e56f71edaf In startBuilder(), only print the new paths we're building 2012-09-13 10:06:24 -04:00
Eelco Dolstra 4fca02077c Handle gc-keep-outputs and gc-keep-derivations both enabled
If the options gc-keep-outputs and gc-keep-derivations are both
enabled, you can get a cycle in the liveness graph.  There was a hack
to handle this, but it didn't work with multiple-output derivations,
causing the garbage collector to fail with errors like ‘error: cannot
delete path `...' because it is in use by `...'’.  The garbage
collector now handles strongly connected components in the liveness
graph as a unit and decides whether to delete all or none of the paths
in an SCC.
2012-09-12 18:49:35 -04:00
Eelco Dolstra 479e9172b3 Build hook: Pass the timeout to the remote builder
Note that this will only work if the client has a very recent Nix
version (post 15e1b2c223), otherwise the
--option flag will just be ignored.

Fixes #50.
2012-09-12 12:18:14 -04:00
Eelco Dolstra 5e2ffd0b8a Fix "non-zero padding" error
Probably it's not a good idea to pass a temporary object to
StringSource.
2012-09-11 19:09:01 -04:00
Eelco Dolstra 8cf672091e Support building a derivation if some outputs are already valid (non-chroot case)
This uses scary hash rewriting.

Fixes #21.
2012-09-11 18:39:22 -04:00
Eelco Dolstra 9dbda2b3fe Remove debug line 2012-09-11 17:05:35 -04:00
Eelco Dolstra a2785b7391 Support building a derivation if some outputs are already valid
This handles the chroot and build hook cases, which are easy.
Supporting the non-chroot-build case will require more work (hash
rewriting!).

Issue #21.
2012-09-11 16:59:59 -04:00
Eelco Dolstra 295027f533 Include config.h before any other header
"config.h" must be included first, because otherwise the compiler
might not see the right value of _FILE_OFFSET_BITS.  We've had this
before; see 705868a8a9.  In this case,
GCC would compute a different address for ‘settings.useSubstitutes’ in
misc.cc because of the off_t in ‘settings’.

Reverts 3854fc9b42.

http://hydra.nixos.org/build/3016700
2012-09-11 14:45:42 -04:00
Eelco Dolstra f7b650d234 Make "nix-instantiate -" interruptible 2012-08-28 11:47:26 -04:00
Eelco Dolstra cfd968dd94 Fix stupid type error in calling std::max 2012-08-27 14:17:13 -04:00
Eelco Dolstra e94806d030 Merge branch 'master' into no-manifests 2012-08-27 11:09:07 -04:00
Eelco Dolstra a9e6752bbd Include the output name in the GC root link
Output names are now appended to resulting GC symlinks, e.g. by
nix-build.  For backwards compatibility, if the output is named "out",
nothing is appended.  E.g. doing "nix-build -A foo" on a derivation
that produces outputs "out", "bin" and "dev" will produce symlinks
"./result", "./result-bin" and "./result-dev", respectively.
2012-08-24 16:58:11 -04:00
Eelco Dolstra 4aa1e5c554 Receive reserveSpace before calling startWork()
Otherwise we can get a SIGPOLL.  Reported by Ludovic.
2012-08-22 10:58:24 -04:00
Eelco Dolstra d950cfe70b Check if MS_PRIVATE is defined
http://hydra.nixos.org/build/2955671
2012-08-20 15:55:49 -04:00
Eelco Dolstra 56e30e161c In the chroot, make all mounted filesystems private
This is required on systemd, which mounts filesystems as "shared"
subtrees.  Changes to shared trees in a private mount namespace are
propagated to the outside world, which is bad.
2012-08-20 15:27:30 -04:00
Eelco Dolstra f0eab0636b Don't bind-mount /proc since we mount our own 2012-08-20 15:27:00 -04:00
Eelco Dolstra 862c4c5ec5 Fix 1755 permission on temporary directories left behind by ‘-K’ 2012-08-19 16:32:42 -04:00
Eelco Dolstra 767101824a Avoid concatenating lists of one string 2012-08-13 15:10:29 -04:00
Eelco Dolstra e5c589d271 Don't allocate empty lists
This saves about 4 MB when evaluating a NixOS system configuration.
2012-08-13 15:02:09 -04:00
Eelco Dolstra 3e89ef597c Optimise concatenating a list to an empty list
More precisely, in concatLists, if all lists except one are empty,
then just return the non-empty list.  This reduces the number of list
element allocations by 32% when evaluating a NixOS system
configuration.
2012-08-13 14:58:54 -04:00
Eelco Dolstra 9c2d63084b Add a primop ‘elemAt’ to get an element from a list 2012-08-13 13:46:42 -04:00
Eelco Dolstra 198d0338be Add a primop ‘concatLists’
This can serve as a generic efficient list builder.  For instance, the
function ‘catAttrs’ in Nixpkgs can be rewritten from

  attr: l: fold (s: l: if hasAttr attr s then [(getAttr attr s)] ++ l else l) [] l

to

  attr: l: builtins.concatLists (map (s: if hasAttr attr s then [(getAttr attr s)] else []) l)

Statistics before:

  time elapsed: 1.08683
  size of a value: 24
  environments allocated: 1384376 (35809568 bytes)
  list elements: 6946783 (55574264 bytes)
  list concatenations: 37434
  values allocated: 1760440 (42250560 bytes)
  attribute sets allocated: 392040
  right-biased unions: 186334
  values copied in right-biased unions: 591137
  symbols in symbol table: 18273
  number of thunks: 1297673
  number of thunks avoided: 1380759
  number of attr lookups: 430802
  number of primop calls: 628912
  number of function calls: 1333544

Statistics after (including new catAttrs):

  time elapsed: 0.959854
  size of a value: 24
  environments allocated: 1010198 (26829296 bytes)
  list elements: 1984878 (15879024 bytes)
  list concatenations: 30488
  values allocated: 1589760 (38154240 bytes)
  attribute sets allocated: 392040
  right-biased unions: 186334
  values copied in right-biased unions: 591137
  symbols in symbol table: 18274
  number of thunks: 1040925
  number of thunks avoided: 1038428
  number of attr lookups: 438419
  number of primop calls: 474844
  number of function calls: 959366
2012-08-13 01:53:10 -04:00
Eelco Dolstra b9e5b908ed Provide an efficient implementation of ‘elem’
The one in Nixpkgs is O(n^2), this one is O(n).  Big reduction in the
number of list allocations.

Statistics before (on a NixOS system config):

  time elapsed: 1.17982
  size of a value: 24
  environments allocated: 1543334 (39624560 bytes)
  list elements: 9612638 (76901104 bytes)
  list concatenations: 37434
  values allocated: 1854933 (44518392 bytes)
  attribute sets allocated: 392040
  right-biased unions: 186334
  values copied in right-biased unions: 591137
  symbols in symbol table: 18272
  number of thunks: 1392467
  number of thunks avoided: 1507311
  number of attr lookups: 430801
  number of primop calls: 691600
  number of function calls: 1492502

Statistics after:

  time elapsed: 1.08683
  size of a value: 24
  environments allocated: 1384376 (35809568 bytes)
  list elements: 6946783 (55574264 bytes)
  list concatenations: 37434
  values allocated: 1760440 (42250560 bytes)
  attribute sets allocated: 392040
  right-biased unions: 186334
  values copied in right-biased unions: 591137
  symbols in symbol table: 18273
  number of thunks: 1297673
  number of thunks avoided: 1380759
  number of attr lookups: 430802
  number of primop calls: 628912
  number of function calls: 1333544
2012-08-13 01:05:35 -04:00
Eelco Dolstra 4ccd48ce24 Add a "filter" primop
Evaluation of a NixOS configuration spends quite a lot of time in the
"filter" function in Nixpkgs.  As implemented in Nixpkgs, this is a
O(n^2) operation, so it's a good candidate for providing a more
efficient (i.e. primop) implementation.  Using it gives a ~10% speed
increase and a significant reduction in the number of evaluations.

Statistics before (on a NixOS system config):

  time elapsed: 1.3258
  size of a value: 24
  environments allocated: 1980939 (50127080 bytes)
  list elements: 14679308 (117434464 bytes)
  list concatenations: 50828
  values allocated: 2098938 (50374512 bytes)
  attribute sets allocated: 392040
  right-biased unions: 186334
  values copied in right-biased unions: 591137
  symbols in symbol table: 18271
  number of thunks: 1645752
  number of thunks avoided: 1921196
  number of attr lookups: 430798
  number of primop calls: 838807
  number of function calls: 1930107

Statistics after:

  time elapsed: 1.17982
  size of a value: 24
  environments allocated: 1543334 (39624560 bytes)
  list elements: 9612638 (76901104 bytes)
  list concatenations: 37434
  values allocated: 1854933 (44518392 bytes)
  attribute sets allocated: 392040
  right-biased unions: 186334
  values copied in right-biased unions: 591137
  symbols in symbol table: 18272
  number of thunks: 1392467
  number of thunks avoided: 1507311
  number of attr lookups: 430801
  number of primop calls: 691600
  number of function calls: 1492502
2012-08-13 00:28:08 -04:00
Eelco Dolstra 62f72eb9e1 Add some more evaluations stats 2012-08-12 23:41:48 -04:00
Eelco Dolstra e82767910c Add some basic profiling support to the evaluator
Setting the environment variable NIX_COUNT_CALLS to 1 enables some
basic profiling in the evaluator.  It will count calls to functions
and primops as well as evaluations of attributes.

For example, to see where evaluation of a NixOS configuration spends
its time:

$ NIX_SHOW_STATS=1 NIX_COUNT_CALLS=1 ./src/nix-instantiate/nix-instantiate '<nixos>' -A system --readonly-mode
...
calls to 39 primops:
    239532 head
    233962 tail
    191252 hasAttr
...
calls to 1595 functions:
    224157 `/nix/var/nix/profiles/per-user/root/channels/nixos/nixpkgs/pkgs/lib/lists.nix:17:19'
    221767 `/nix/var/nix/profiles/per-user/root/channels/nixos/nixpkgs/pkgs/lib/lists.nix:17:14'
    221767 `/nix/var/nix/profiles/per-user/root/channels/nixos/nixpkgs/pkgs/lib/lists.nix:17:10'
...
evaluations of 7088 attributes:
    167377 undefined position
    132459 `/nix/var/nix/profiles/per-user/root/channels/nixos/nixpkgs/pkgs/lib/attrsets.nix:119:41'
     47322 `/nix/var/nix/profiles/per-user/root/channels/nixos/nixpkgs/pkgs/lib/attrsets.nix:13:21'
...
2012-08-12 23:29:28 -04:00
Eelco Dolstra 325d1cfebf Don't warn about maximum link count exceeded on 0-byte files 2012-08-07 16:22:54 -04:00
Eelco Dolstra d025142f52 Handle amount of disk space saved by hard linking being negative
Fixes bogus messages like "currently hard linking saves
17592186044416.00 MiB".
2012-08-05 21:45:27 -04:00
Eelco Dolstra b6c989b801 Fix race condition when two processes create a hard link to a file in .links
This is a problem because one process may set the immutable bit before
the second process has created its link.

Addressed random Hydra failures such as:

error: cannot rename `/nix/store/.tmp-link-17397-1804289383' to
`/nix/store/rsvzm574rlfip3830ac7kmaa028bzl6h-nixos-0.1pre-git/upstart-interface-version':
Operation not permitted
2012-08-05 21:41:44 -04:00
Eelco Dolstra 108e14bb18 Fix race condition when two processes create the same link in /nix/store/.links 2012-08-05 18:17:55 -04:00
Eelco Dolstra 6763084ae5 Count bytes freed deleting unused links 2012-08-01 22:43:03 -04:00
Eelco Dolstra 01d56c1eec Drop the block count in the garbage collector 2012-08-01 22:34:46 -04:00
Eelco Dolstra 967d066d8e nix-store --gc: Make ‘--max-freed 0’ do the right thing
That is, delete almost nothing (it will still remove unused links from
/nix/store/.links).
2012-08-01 19:14:58 -04:00
Eelco Dolstra 1df702d347 removeUnusedLinks(): Print stats on disk space saved by hard linking 2012-08-01 19:01:50 -04:00
Eelco Dolstra 9c2decaa19 Merge branch 'master' into no-manifests 2012-08-01 18:03:49 -04:00
Eelco Dolstra 79bba3782c Doh 2012-08-01 17:21:47 -04:00
Eelco Dolstra ca94b38371 nix-env: Ignore manifest.nix when recursing into ~/.nix-defexpr
Channels are implemented using a profile now, and profiles contain a
manifest.nix file.  This should be ignored to prevent bogus packages
from showing up in nix-env.
2012-08-01 17:17:07 -04:00
Eelco Dolstra 234ce610e0 Doh 2012-08-01 16:09:47 -04:00
Eelco Dolstra 7b10562370 Make ‘nix-store --optimise’ interruptible 2012-08-01 16:06:49 -04:00
Eelco Dolstra c770a2422a Report substituter errors to clients of the Nix daemon 2012-08-01 11:19:24 -04:00
Eelco Dolstra eb7849e3a2 Prevent an injection attack in passing untrusted options to substituters 2012-07-31 18:50:32 -04:00
Eelco Dolstra 90d9c58d4d Pass all --option flags to the daemon 2012-07-31 18:19:44 -04:00
Eelco Dolstra 89a8207029 Add an option ‘build-fallback’ (equivalent to the --fallback flag) 2012-07-31 17:56:02 -04:00
Eelco Dolstra 97421eb5ec Refactor settings processing
Put all Nix configuration flags in a Settings object.
2012-07-30 19:55:41 -04:00
Eelco Dolstra d50d7a2874 Whitespace 2012-07-30 17:13:25 -04:00
Eelco Dolstra d059bf48e4 Pass configuration settings to the substituters
Previously substituters could read nix.conf themselves, but this
didn't take --option flags into account.
2012-07-30 16:09:54 -04:00
Eelco Dolstra f9613da180 Remove unused variables 2012-07-30 15:43:37 -04:00
Eelco Dolstra 6183cf2f19 Fix whitespace 2012-07-30 15:42:18 -04:00
Eelco Dolstra 73acb8b836 Let build.cc verify the expected hash of a substituter's output
Since SubstitutionGoal::finished() in build.cc computes the hash
anyway, we can prevent the inefficiency of computing the hash twice by
letting the substituter tell Nix about the expected hash, which can
then verify it.
2012-07-27 12:16:02 -04:00
Eelco Dolstra fbf59d95f6 Remove more tabs 2012-07-27 10:56:33 -04:00
Eelco Dolstra b4ea83249b Remove trailing whitespace / tabs 2012-07-27 09:59:18 -04:00
Eelco Dolstra 50395b71a9 Fix the substituter tests 2012-07-26 17:36:07 -04:00
Eelco Dolstra 8c79100839 Merge branch 'master' into no-manifests 2012-07-26 15:14:33 -04:00
Eelco Dolstra 3a4623afbb Set permissions on temporary build directories to 0700
Fixes #39.
2012-07-26 15:04:40 -04:00
Shea Levy f5954e2d94 prim_import: When importing .drvs, allocate the intermediate attrset on the heap just in case it escapes the stack frame. 2012-07-25 09:30:17 -04:00
Shea Levy b1112bbef1 import: If the path is a valid .drv file, parse it and generate a derivation attrset.
The generated attrset has drvPath and outPath with the right string context, type 'derivation', outputName with
the right name, all with a list of outputs, and an attribute for each output.

I see three uses for this (though certainly there may be more):

* Using derivations generated by something besides nix-instantiate (e.g. guix)

* Allowing packages provided by channels to be used in nix expressions. If a channel installed a valid deriver
  for each package it provides into the store, then those could be imported and used as dependencies or installed
  in environment.systemPackages, for example.

* Enable hydra to be consistent in how it treats inputs that are outputs of another build. Right now, if an
  input is passed as an argument to the job, it is passed as a derivation, but if it is accessed via NIX_PATH
  (i.e. through the <> syntax), then it is a path that can be imported. This is problematic because the build
  being depended upon may have been built with non-obvious arguments passed to its jobset file. With this
  feature, hydra can just set the name of that input to the path to its drv file in NIX_PATH
2012-07-25 09:30:17 -04:00
Eelco Dolstra e98c029717 Handle platforms that don't support linking to a symlink
E.g. Darwin doesn't allow this.
2012-07-23 18:42:18 -04:00
Eelco Dolstra fd63c8bfcd Unlink the right file 2012-07-23 18:06:37 -04:00
Eelco Dolstra 680ab6f83d Garbage collect unused links in /nix/store/.links
Incremental optimisation requires creating links in /nix/store/.links
to all files in the store.  However, this means that if we delete a
store path, no files are actually deleted because links in
/nix/store/.links still exists.  So we need to check /nix/store/.links
for files with a link count of 1 and delete them.
2012-07-23 17:14:16 -04:00
Eelco Dolstra 6193105710 Automatically optimise the Nix store when a new path is added
Auto-optimisation is enabled by default.  It can be turned off by
setting auto-optimise-store to false in nix.conf.
2012-07-23 17:14:15 -04:00
Eelco Dolstra 564fb7d9fa optimiseStore(): Use a content-addressed file store in /nix/store/.links
optimiseStore() now creates persistent, content-addressed hard links
in /nix/store/.links.  For instance, if it encounters a file P with
hash H, it will create a hard link

  P' = /nix/store/.link/<H>

to P if P' doesn't already exist; if P' exist, then P is replaced by a
hard link to P'.  This is better than the previous in-memory map,
because it had the tendency to unnecessarily replace hard links with a
hard link to whatever happened to be the first file with a given hash
it encountered.  It also allows on-the-fly, incremental optimisation.
2012-07-23 17:14:15 -04:00
Eelco Dolstra 6852289c46 Use lutimes() if available to canonicalise the timestamp of symlinks
Also use utimes() instead of utime() if lutimes() is not available.
2012-07-23 16:52:25 -04:00
Eelco Dolstra b7fd2c2822 Use "#pragma once" to prevent repeated header file inclusion 2012-07-18 14:59:03 -04:00
Eelco Dolstra fe241ece29 Merge branch 'master' into no-manifests 2012-07-18 10:47:59 -04:00
Eelco Dolstra ccc52adfb2 Add function queryPathFromHashPart()
To implement binary caches efficiently, Hydra needs to be able to map
the hash part of a store path (e.g. "gbg...zr7") to the full store
path (e.g. "/nix/store/gbg...kzr7-subversion-1.7.5").  (The binary
cache mechanism uses hash parts as a key for looking up store paths to
ensure privacy.)  However, doing a search in the Nix store for
/nix/store/<hash>* is expensive since it requires reading the entire
directory.  queryPathFromHashPart() prevents this by doing a cheap
database lookup.
2012-07-17 18:55:39 -04:00
Eelco Dolstra 3a9fdf2747 Return an exit code of 100 for cached failed builds
Exit code 100 should be returned for all permanent failures.  This
includes cached failures.

Fixes #34.
2012-07-17 15:55:30 -04:00
Eelco Dolstra 1217204c81 Remove dead code 2012-07-17 14:07:52 -04:00
Eelco Dolstra 6c01fb4d68 Update Nix 1.1 release notes 2012-07-17 10:06:20 -04:00
Eelco Dolstra 53b24f3518 Allow disabling log compression 2012-07-17 09:40:12 -04:00
Eelco Dolstra a7a43adb79 builtins.storePath: resolve symlinks
Needed for Charon/Hydra interaction.
2012-07-12 18:25:01 -04:00
Eelco Dolstra f2bdc87595 Update the other substituters 2012-07-11 18:52:09 -04:00
Eelco Dolstra 09a6321aeb Replace hasSubstitutes() with querySubstitutablePaths()
querySubstitutablePaths() takes a set of paths, so this greatly
reduces daemon <-> client latency.
2012-07-11 17:52:18 -04:00
Eelco Dolstra 58ef4d9a95 Add a function queryValidPaths()
queryValidPaths() combines multiple calls to isValidPath() in one.
This matters when using the Nix daemon because it reduces latency.
For instance, on "nix-env -qas \*" it reduces execution time from 5.7s
to 4.7s (which is indistinguishable from the non-daemon case).
2012-07-11 11:08:47 -04:00
Eelco Dolstra 667d5f1936 Rename queryValidPaths() to queryAllValidPaths() 2012-07-11 10:49:04 -04:00
Eelco Dolstra eb3036da87 Implement querySubstitutablePathInfos() in the daemon
Also removed querySubstitutablePathInfo().
2012-07-11 10:43:24 -04:00
Eelco Dolstra 6586414bc7 nix-env: Determine which paths have substitutes in parallel 2012-07-11 10:14:06 -04:00
Eelco Dolstra 98a423b75a prim_import(): prefetch substitute info in parallel using queryMissing() 2012-07-09 09:59:34 -04:00
Eelco Dolstra 425cc612ad build.cc: Don't use hasSubstitute()
Instead make a single call to querySubstitutablePathInfo() per
derivation output.  This is faster and prevents having to implement
the "have" function in the binary cache substituter.
2012-07-08 18:39:24 -04:00
Eelco Dolstra 11800e6198 download-from-binary-cache: parallelise fetching of NAR info files
Getting substitute information using the binary cache substituter has
non-trivial latency overhead.  A package or NixOS system configuration
can have hundreds of dependencies, and in the worst case (when the
local info cache is empty) we have to do a separate HTTP request for
each of these.  If the ping time to the server is t, getting N info
files will take tN seconds; e.g., with a ping time of 0.1s to
nixos.org, sequentially downloading 1000 info files (a typical NixOS
config) will take at least 100 seconds.

To fix this problem, the binary cache substituter can now perform
requests in parallel.  This required changing the substituter
interface to support a function querySubstitutablePathInfos() that
queries multiple paths at the same time, and rewriting queryMissing()
to take advantage of parallelism.  (Due to local caching,
parallelising queryMissing() is sufficient for most use cases, since
it's almost always called before building a derivation and thus fills
the local info cache.)

For example, parallelism speeds up querying all 1056 paths in a
particular NixOS system configuration from 116s to 2.6s.  It works so
well because the eccentricity of the top-level derivation in the
dependency graph is only 9.  So we only need 10 round-trips (when
using an unlimited number of parallel connections) to get everything.

Currently we do a maximum of 150 parallel connections to the server.
Thus it's important that the binary cache server (e.g. nixos.org) has
a high connection limit.  Alternatively we could use HTTP pipelining,
but WWW::Curl doesn't support it and libcurl has a hard-coded limit of
5 requests per pipeline.
2012-07-06 19:08:20 -04:00
Eelco Dolstra 1aba0bf0fa nix-store -r: do substitutions in parallel
I.e. when multiple non-derivation arguments are passed to ‘nix-store
-r’ to be substituted, do them in parallel.
2012-06-27 16:58:15 -04:00
Eelco Dolstra 42f5a2fc29 Mount an empty /dev/shm tmpfs in the chroot
This ensures that whatever the builder writes in /dev/shm is
automatically cleaned up.
2012-06-27 09:52:27 -04:00
Eelco Dolstra 3ee208516f Check the return code of the clone() call 2012-06-27 09:52:06 -04:00
Eelco Dolstra 1db38ae81b When using chroots, use a private PID namespace
In a private PID namespace, processes have PIDs that are separate from
the rest of the system.  The initial child gets PID 1.  Processes in
the chroot cannot see processes outside of the chroot.  This improves
isolation between builds.  However, processes on the outside can see
processes in the chroot and send signals to them (if they have
appropriate rights).

Since the builder gets PID 1, it serves as the reaper for zombies in
the chroot.  This might turn out to be a problem.  In that case we'll
need to have a small PID 1 process that sits in a loop calling wait().
2012-06-25 15:45:16 -04:00
Eelco Dolstra 5489086456 Use a private UTS namespace to provide a deterministic host/domain name to builders
In chroot builds, set the host name to "localhost" and the domain name
to "(none)" (the latter being the kernel's default).  This improves
determinism a bit further.

P.S. I have to idea what UTS stands for.
2012-06-25 14:12:17 -04:00
Eelco Dolstra 723a68c826 Improve error message 2012-06-23 00:57:14 -04:00
Eelco Dolstra 7ffa523fd1 In chroot builds, use a private SysV IPC namespace
This improves isolation a bit further, and it's just one extra flag in
the unshare() call.

P.S. It would be very cool to use CLONE_NEWPID (to put the builder in
a private PID namespace) as well, but that's slightly more risky since
having a builder start as PID 1 may cause problems.
2012-06-23 00:51:40 -04:00
Eelco Dolstra df716c98d2 In chroot builds, use a private network namespace
On Linux it's possible to run a process in its own network namespace,
meaning that it gets its own set of network interfaces, disjunct from
the rest of the system.  We use this to completely remove network
access to chroot builds, except that they get a private loopback
interface.  This means that:

- Builders cannot connect to the outside network or to other processes
  on the same machine, except processes within the same build.

- Vice versa, other processes cannot connect to processes in a chroot
  build, and open ports/connections do not show up in "netstat".

- If two concurrent builders try to listen on the same port (e.g. as
  part of a test), they no longer conflict with each other.

This was inspired by the "PrivateNetwork" flag in systemd.
2012-06-23 00:28:35 -04:00
Eelco Dolstra 2f3f413e91 Support socket-based, on-demand activation of the Nix daemon with systemd
Systemd can start the Nix daemon on demand when the Nix daemon socket
is first accessed.  This is signalled through the LISTEN_FDS
environment variable, so all we need to do is check for that and then
use file descriptor 3 as the listen socket instead of creating one
ourselves.
2012-06-18 23:01:46 -04:00
Eelco Dolstra f5398d374b Compress build logs on the fly using bzip2 2012-05-30 10:12:29 -04:00
Eelco Dolstra 881beb170d "nix-store -l": support compressed logs 2012-05-30 00:00:02 -04:00
Eelco Dolstra 4bc4da331a Reserve some disk space for the garbage collector
We can't open a SQLite database if the disk is full.  Since this
prevents the garbage collector from running when it's most needed, we
reserve some dummy space that we can free just before doing a garbage
collection.  This actually revives some old code from the Berkeley DB
days.

Fixes #27.
2012-05-29 22:59:12 -04:00
Eelco Dolstra 2c26985835 Add option ‘build-keep-log’ to enable/disable writing of build logs
Fixes #26.
2012-05-29 16:42:05 -04:00
Eelco Dolstra db5b86ef13 * Add an option ‘build-use-substitutes’, which can be set to ‘false’
to disable use of substitutes; i.e., force building from source.
  Fixes Nix/221.
2012-04-30 19:15:34 -04:00
Eelco Dolstra 46cdc6ad51 Handle EPERM when creating a hard link for the chroot
There is a race condition when doing parallel builds with chroots and
the immutable bit enabled.  One process may call makeImmutable()
before the other has called link(), in which case link() will fail
with EPERM.  We could retry or wrap the operation in a lock, but since
this condition is rare and I'm lazy, we just use the existing copy
fallback.

Fixes #9.
2012-04-30 10:58:04 -04:00
Eelco Dolstra 6387830c3b Merge pull request #2 from viric/master
Again, adding the sync option
2012-04-23 03:29:03 -07:00
Eelco Dolstra 9cd3ff1059 nix-instantiate: default to "default.nix" if no arguments are given 2012-04-17 17:19:43 +02:00
Eelco Dolstra 8745fade03 Added utility command ‘nix-instantiate --find-file’ to look up a file in Nix's search path 2012-04-17 17:14:14 +02:00
Eelco Dolstra 1132dd27ea Fix obscure race condition in GC root creation
This should fix rare Hydra errors of the form:

error: symlinking `/nix/var/nix/gcroots/per-user/hydra/hydra-roots/7sfhs5fdmjxm8sqgcpd0pgcsmz1kq0l0-nixos-iso-0.1pre33785-33795' to `/nix/store/7sfhs5fdmjxm8sqgcpd0pgcsmz1kq0l0-nixos-iso-0.1pre33785-33795': File exists
2012-04-16 18:47:01 +02:00
Eelco Dolstra 154aa7f71a Set a few more close-on-exec flags 2012-04-15 00:42:16 +02:00
Eelco Dolstra 31e34fcf93 Close almost all file descriptors in the builder
This regression was accidentally introduced in
35355fc1fc.
2012-04-15 00:20:32 +02:00
Eelco Dolstra ef902274fd Remove unnecessary "system" argument 2012-04-14 18:48:11 +02:00
Eelco Dolstra 00c98a6bef Use Bison 2.5 2012-04-13 14:28:26 +02:00
Eelco Dolstra f2467eb6a0 On Linux, pretend we're building on Linux 2.6
Setting the UNAME26 personality causes "uname" to return "2.6.x",
regardless of the kernel version.  This improves determinism in
a few misbehaved packages.
2012-04-05 13:03:19 +02:00
Eelco Dolstra 34ea91b259 Include --keep-going in --help 2012-04-04 16:22:32 +02:00
Eelco Dolstra 446b827bae Mac OS X fix 2012-03-26 23:18:36 +02:00
Eelco Dolstra 480dda0e42 Delete non-directory valid paths right away
It's unlikely that rename() is faster than unlink() on a regular file
or symlink, so don't bother.
2012-03-26 20:56:30 +02:00
Eelco Dolstra 117670be57 Make the garbage collector more concurrent
Make the garbage collector more concurrent by deleting valid paths
outside the region where we're holding the global GC lock.  This
should greatly reduce the time during which new builds are blocked,
since the deletion accounts for the vast majority of the time spent in
the GC.

To ensure that this is safe, the valid paths are invalidated and
renamed to some arbitrary path while we're holding the lock.  This
ensures that we when we finally delete the path, it's not a (newly)
valid or locked path.
2012-03-26 20:43:33 +02:00
Eelco Dolstra 8be1979f1a Remove the --max-links GC option
We don't need this anymore now that current filesystems support more
than 32,000 files in a directory.
2012-03-26 20:00:02 +02:00
Lluís Batlle i Rossell 85799bf89e Fixing the default of sync-before-registering
Setting 'false' as default, as suggested by Eelco.

I also added a comment about the setting in the code.
2012-03-22 20:05:54 +01:00
Lluís Batlle i Rossell 25de80e2b6 Adding a nix option to sync before registering a path, for non-ext*
filesystems.
2012-03-22 19:57:42 +01:00
Eelco Dolstra 19d9762ad5 nix-store --clear-failed-paths: Clear derivation outputs
If the argument to ‘nix-store --clear-failed-paths’ is a derivation,
then clear the failed state of its outputs.
2012-03-20 18:23:26 +01:00
Eelco Dolstra b006a31d52 Drop the externals directory
Nix now requires SQLite and bzip2 to be pre-installed.  SQLite is
detected using pkg-config.  We required DBD::SQLite anyway, so
depending on SQLite is not a big problem.

The --with-bzip2, --with-openssl and --with-sqlite flags are gone.
2012-03-18 23:54:57 +01:00
Eelco Dolstra bd50c01972 Ensure that Perl processes delete their entry in the temproots directory
By moving the destructor object to libstore.so, it's also run when
download-using-manifests and nix-prefetch-url exit.  This prevents
them from cluttering /nix/var/nix/temproots with stale files.
2012-03-13 17:07:49 +01:00
Eelco Dolstra 605b16cd7b Fix compilation on FreeBSD
http://hydra.nixos.org/build/2213576

Not sure why compilation doesn't fail on other platforms...
2012-03-05 22:04:40 +01:00
Eelco Dolstra 35355fc1fc Set the close-on-exec flag on file descriptors 2012-03-05 20:29:00 +01:00
Eelco Dolstra 7b22bec252 Don't leak a file descriptor in commonChildInit() 2012-03-05 20:28:09 +01:00
Eelco Dolstra 1d487dc6a6 nix-worker: put the pid of the caller in argv[1]
This is useful for debugging.
2012-03-05 19:19:29 +01:00
Eelco Dolstra 2b4964f319 Restore progress indication during nix-copy-closure 2012-03-05 18:13:44 +01:00
Eelco Dolstra 8afd28a922 Remove dependency on sqlite3_table_column_metadata
Not all SQLite builds have the function sqlite3_table_column_metadata.
We were only using it in a schema upgrade check for compatibility with
databases that were probably never seen in the wild.  So remove it.
2012-03-01 16:06:49 +01:00
Eelco Dolstra 1c94524458 Fix an uninitialised variable
The variable ‘useChroot’ was not initialised properly.  This caused
random failures if using the build hook.  Seen on Mac OS X 10.7 with Clang.
Thanks to KolibriFX for finding this :-)
2012-03-01 16:06:49 +01:00
Eelco Dolstra 6fe13e6aba Fix chroots builds
Chroots are initialised by hard-linking inputs from the Nix store to
the chroot.  This doesn't work if the input has its immutable bit set,
because it's forbidden to create hard links to immutable files.  So
temporarily clear the immutable bit when creating and destroying the
chroot.

Note that making regular files in the Nix store immutable isn't very
reliable, since the bit can easily become cleared: for instance, if we
run the garbage collector after running ‘nix-store --optimise’.  So
maybe we should only make directories immutable.
2012-02-18 01:23:52 +01:00
Eelco Dolstra bd013b6f98 On Linux, make the Nix store really read-only by using the immutable bit
I was bitten one time too many by Python modifying the Nix store by
creating *.pyc files when run as root.  On Linux, we can prevent this
by setting the immutable bit on files and directories (as in ‘chattr
+i’).  This isn't supported by all filesystems, so it's not an error
if setting the bit fails.  The immutable bit is cleared by the garbage
collector before deleting a path.  The only tricky aspect is in
optimiseStore(), since it's forbidden to create hard links to an
immutable file.  Thus optimiseStore() temporarily clears the immutable
bit before creating the link.
2012-02-15 01:31:56 +01:00
Eelco Dolstra 5e57047d87 Fix a broken guard around utime()
Because of an outdated check for a timestamp of 0, we were calling
utime() even when it wasn't necessary.
2012-02-15 01:00:30 +01:00
Eelco Dolstra 58ac7a17a4 Don't use deletePath() to delete a single file 2012-02-15 00:28:01 +01:00
Eelco Dolstra e9fc91df45 Fix error message
This fixes the error message

  error: file `' was not found in the Nix search path (add it using $NIX_PATH or -I)
2012-02-09 18:56:48 +01:00
Eelco Dolstra d5a5a83ad4 Use data() instead of c_str() where appropriate 2012-02-09 18:27:45 +01:00