Getting the names of all environment variables is tricky. The previous
implementation easily got confused by multi-line variables. The new
one is more reliable but not still not perfect.
This works around a segfault in Bash 4.3, where the expression
"${!var}" (where var="-9") crashes under certain conditions.
http://hydra.nixos.org/build/16693445
Otherwise, stdenv won't have a reference to e.g. patchelf on Linux
(because it was passed in by mkDerivation). This causes the installer
tests to fail, because having "stdenv" in the installation CD closure
is not enough to pull in all stdenv packages.
http://hydra.nixos.org/build/16546643
Now gcc is just another build input, making it possible in the future
to have a stdenv that doesn't depend on a C compiler. This is very
useful on NixOS, since it would allow trivial builders like
writeTextFile to work without pulling in the C compiler.
If $src refers to a directory, then always copy it. Previously, we
checked the extension first, so if the directory had an extension like
.tar, unpackPhase would fail.
If a build input is a regular file, use it as a setup hook. This makes
setup hooks more efficient to create: you don't need a derivation that
copies them to $out/nix-support/setup-hook, instead you can use the
file as is.
You can now register multiple values per named hook, e.g.
addHook preConfigure "echo foo"
addHook preConfigure "echo bar"
will cause ‘runHook preConfigure’ to run both ‘echo foo’ and ‘echo
bar’ (in that order). It will also call the shell function
preConfigure() or eval the shell variable $preConfigure, if
defined. Thus, if you don't call addHook, it works like the old hook
mechanism.
Allowing multiple hooks makes stdenv more modular and extensible. For
instance, multiple setup hooks can define a preFixup hook, and all of
these will be executed.
setup.sh uses the anti-pattern `for f in $(find ...); do` in several
places. `find` returns one path per line, but `for` splits its arguments
by words, so paths which contain spaces are incorrectly split! The
correct way is `find ... | while read f; do`
Treating fixupPhase specially is really ugly. Also, it collides with
the work in the multiple-outputs branch (which already has support for
fixing up all outputs).
Partial revert of 0a44a09121.
Some programs, e.g. guile-config, has a shebang that ends in '\':
#!/usr/bin/guile-1.8 \
-e main -s
!#
;;;; guile-config --- utility for linking programs with Guile
;;;; Jim Blandy <jim@red-bean.com> --- September 1997
This currently breaks patchShebangs:
$ read oldPath arg0 args <<< 'shebang \'; echo $?
1
$ echo $oldPath
shebang
$ echo $arg0
$ echo $args
(And setup.sh/patchShebangs is run with 'set -e' so any command that
return non-zero aborts the build.)
Fix by telling 'read' to not interpret backslashes (with the -r flag):
$ read -r oldPath arg0 args <<< 'shebang \'; echo $?
0
$ echo $oldPath
shebang
$ echo $arg0
\
$ echo $args
Also needed: escape the escape characters so that sed doesn't interpret
them.
patchShebangs has a bug that shows itself on files that have the
executable bit set but have no shebang (i.e. a blank/empty first line).
The shell would then evaluate this:
if [ != '#!' ]; then
# not evaluated
fi
With proper quoting we get the correct behaviour:
if [ "" != '#!' ]; then
# this will be evaluated
fi
When building e.g. perl for the first time there is no perl in PATH yet,
so command -v perl will fail.
This brings back the previous behaviour of silently not patching
shebangs for which there is no available command in PATH.
Currently "/usr/bin/env python" is rewritten to "/nix/store/.../env
python". That doesn't really improve anything because the interpreter
still have to be located in $PATH at runtime. The result is that many
nix package expressions do .../bin/env fixup themselves.
Instead of everyone having to do this patching locally, add the
functionality to the standard environment patchShebangs function so that
everyone can benefit.
