config.environ: delay export of A and AA (bug 720180)

bin/eapi.sh

@@ -26,6 +26,15 @@ ___eapi_has_S_WORKDIR_fallback() {
 
 # VARIABLES
 
+___eapi_exports_A() {
+	# https://bugs.gentoo.org/721088
+	true
+}
+
+___eapi_exports_AA() {
+	[[ ${1-${EAPI-0}} =~ ^(0|1|2|3)$ ]]
+}
+
 ___eapi_has_prefix_variables() {
 	[[ ! ${1-${EAPI-0}} =~ ^(0|1|2)$ || " ${FEATURES} " == *" force-prefix "* ]]
 }

bin/isolated-functions.sh

@@ -107,6 +107,39 @@ __bashpid() {
 	sh -c 'echo ${PPID}'
 }
 
+# @FUNCTION: ___eapi_vars_export
+# @DESCRIPTION:
+# Export variables for the current EAPI. Calls to this function should
+# be delayed until the last moment, since exporting these variables
+# may trigger E2BIG errors suring attempts to execute subprocesses.
+___eapi_vars_export() {
+	source "${T}/environment.unexported" || die
+
+	if ___eapi_exports_A; then
+		export A
+	fi
+
+	if ___eapi_exports_AA; then
+		export AA
+	fi
+}
+
+# @FUNCTION: ___eapi_vars_unexport
+# @DESCRIPTION:
+# Unexport variables that were exported for the current EAPI. This
+# function should be called after an ebuild phase, in order to unexport
+# variables that may trigger E2BIG errors during attempts to execute
+# subprocesses.
+___eapi_vars_unexport() {
+	if ___eapi_exports_A; then
+		export -n A
+	fi
+
+	if ___eapi_exports_AA; then
+		export -n AA
+	fi
+}
+
 __helpers_die() {
 	if ___eapi_helpers_can_die && [[ ${PORTAGE_NONFATAL} != 1 ]]; then
 		die "$@"
@@ -122,6 +155,7 @@ die() {
 
 	set +x # tracing only produces useless noise here
 	local IFS=$' \t\n'
+	___eapi_vars_unexport
 
 	if ___eapi_die_can_respect_nonfatal && [[ $1 == -n ]]; then
 		shift

bin/phase-functions.sh

@@ -146,6 +146,7 @@ __filter_readonly_variables() {
 		fi
 	fi
 
+	___eapi_vars_unexport
 	"${PORTAGE_PYTHON:-/usr/bin/python}" "${PORTAGE_BIN_PATH}"/filter-bash-environment.py "${filtered_vars}" || die "filter-bash-environment.py failed"
 }
 
@@ -212,6 +213,7 @@ __ebuild_phase() {
 
 __ebuild_phase_with_hooks() {
 	local x phase_name=${1}
+	___eapi_vars_export
 	for x in {pre_,,post_}${phase_name} ; do
 		__ebuild_phase ${x}
 	done
@@ -223,6 +225,7 @@ __dyn_pretend() {
 		__vecho ">>> Remove '$PORTAGE_BUILDDIR/.pretended' to force pretend."
 		return 0
 	fi
+	___eapi_vars_export
 	__ebuild_phase pre_pkg_pretend
 	__ebuild_phase pkg_pretend
 	>> "$PORTAGE_BUILDDIR/.pretended" || \
@@ -236,6 +239,7 @@ __dyn_setup() {
 		__vecho ">>> Remove '$PORTAGE_BUILDDIR/.setuped' to force setup."
 		return 0
 	fi
+	___eapi_vars_export
 	__ebuild_phase pre_pkg_setup
 	__ebuild_phase pkg_setup
 	>> "$PORTAGE_BUILDDIR/.setuped" || \
@@ -252,6 +256,7 @@ __dyn_unpack() {
 		install -m${PORTAGE_WORKDIR_MODE:-0700} -d "${WORKDIR}" || die "Failed to create dir '${WORKDIR}'"
 	fi
 	cd "${WORKDIR}" || die "Directory change failed: \`cd '${WORKDIR}'\`"
+	___eapi_vars_export
 	__ebuild_phase pre_src_unpack
 	__vecho ">>> Unpacking source..."
 	__ebuild_phase src_unpack
@@ -387,6 +392,7 @@ __dyn_prepare() {
 
 	trap __abort_prepare SIGINT SIGQUIT
 
+	___eapi_vars_export
 	__ebuild_phase pre_src_prepare
 	__vecho ">>> Preparing source in $PWD ..."
 	__ebuild_phase src_prepare
@@ -424,6 +430,7 @@ __dyn_configure() {
 
 	trap __abort_configure SIGINT SIGQUIT
 
+	___eapi_vars_export
 	__ebuild_phase pre_src_configure
 
 	__vecho ">>> Configuring source in $PWD ..."
@@ -457,6 +464,7 @@ __dyn_compile() {
 
 	trap __abort_compile SIGINT SIGQUIT
 
+	___eapi_vars_export
 	__ebuild_phase pre_src_compile
 
 	__vecho ">>> Compiling source in $PWD ..."
@@ -503,6 +511,7 @@ __dyn_test() {
 	else
 		local save_sp=${SANDBOX_PREDICT}
 		addpredict /
+		___eapi_vars_export
 		__ebuild_phase pre_src_test
 
 		__vecho ">>> Test phase: ${CATEGORY}/${PF}"
@@ -556,6 +565,7 @@ __dyn_install() {
 	eval "[[ -n \$QA_PRESTRIPPED_${ARCH/-/_} ]] && \
 		export QA_PRESTRIPPED_${ARCH/-/_}"
 
+	___eapi_vars_export
 	__ebuild_phase pre_src_install
 
 	if ___eapi_has_prefix_variables; then
@@ -698,6 +708,7 @@ __dyn_install() {
 		--filter-path --filter-sandbox --allow-extra-vars > \
 		"${PORTAGE_BUILDDIR}"/build-info/environment
 	assert "__save_ebuild_env failed"
+	___eapi_vars_unexport
 	cd "${PORTAGE_BUILDDIR}"/build-info || die
 
 	${PORTAGE_BZIP2_COMMAND} -f9 environment
@@ -1096,11 +1107,13 @@ __ebuild_main() {
 		__save_ebuild_env | __filter_readonly_variables \
 			--filter-features > "$T/environment"
 		assert "__save_ebuild_env failed"
+		___eapi_vars_unexport
 		chgrp "${PORTAGE_GRPNAME:-portage}" "$T/environment"
 		chmod g+w "$T/environment"
 	fi
 	[[ -n $PORTAGE_EBUILD_EXIT_FILE ]] && > "$PORTAGE_EBUILD_EXIT_FILE"
 	if [[ -n $PORTAGE_IPC_DAEMON ]] ; then
+		___eapi_vars_unexport
 		[[ ! -s $SANDBOX_LOG ]]
 		"$PORTAGE_BIN_PATH"/ebuild-ipc exit $?
 	fi

lib/portage/package/ebuild/_config/special_env_vars.py

@@ -191,7 +191,7 @@
 # user config variables
 environ_whitelist += ["DOC_SYMLINKS_DIR", "INSTALL_MASK", "PKG_INSTALL_MASK"]
 
-environ_whitelist += ["A", "AA", "CATEGORY", "P", "PF", "PN", "PR", "PV", "PVR"]
+environ_whitelist += ["CATEGORY", "P", "PF", "PN", "PR", "PV", "PVR"]
 
 # misc variables inherited from the calling environment
 environ_whitelist += [
@@ -247,13 +247,21 @@
 
 environ_whitelist_re = re.compile(r"^(CCACHE_|DISTCC_).*")
 
+environ_unexported = frozenset(
+    [
+        "A",
+        "AA",
+    ]
+)
+
 # Filter selected variables in the config.environ() method so that
 # they don't needlessly propagate down into the ebuild environment.
 environ_filter = []
 
 # Exclude anything that could be extremely long here (like SRC_URI)
 # since that could cause execve() calls to fail with E2BIG errors. For
 # example, see bug #262647.
+environ_filter.extend(environ_unexported)
 environ_filter += [
     "DEPEND",
     "RDEPEND",

lib/portage/package/ebuild/config.py

@@ -11,6 +11,7 @@
 import copy
 from itertools import chain
 import grp
+import io
 import logging
 import platform
 import pwd
@@ -31,7 +32,7 @@
     "portage.util.compression_probe:_compressors",
     "portage.util.locale:check_locale,split_LC_ALL",
 )
-from portage import bsd_chflags, load_mod, os, selinux, _unicode_decode
+from portage import bsd_chflags, load_mod, os, selinux, _encodings, _unicode_decode
 from portage.const import (
     CACHE_PATH,
     DEPCACHE_PATH,
@@ -3218,17 +3219,43 @@ def environ(self):
         eapi_attrs = _get_eapi_attrs(eapi)
         phase = self.get("EBUILD_PHASE")
         emerge_from = self.get("EMERGE_FROM")
+        temp_dir = None
         filter_calling_env = False
         if (
             self.mycpv is not None
-            and not (emerge_from == "ebuild" and phase == "setup")
+            and "PORTAGE_BUILDDIR_LOCKED" in self
             and phase not in ("clean", "cleanrm", "depend", "fetch")
         ):
-            temp_dir = self.get("T")
-            if temp_dir is not None and os.path.exists(
-                os.path.join(temp_dir, "environment")
-            ):
-                filter_calling_env = True
+            temp_dir = self["T"]
+            # These variables will exported by ebuild.sh if appropriate
+            # for the current EAPI, but export is delayed since large
+            # values may trigger E2BIG errors during attempts to spawn
+            # subprocesses.
+            unexported = []
+            for key in special_env_vars.environ_unexported:
+                # Don't export AA for EAPIs that forbid it.
+                if key == "AA" and not eapi_exports_AA(eapi):
+                    continue
+                value = self.get(key)
+                if value is not None:
+                    unexported.append((key, value))
+
+            # Write this file even if it's empty, so that ebuild.sh can
+            # rely on its existence.
+            with io.open(
+                os.path.join(temp_dir, "environment.unexported"),
+                mode="wt",
+                encoding=_encodings["repo.content"],
+            ) as f:
+                for key, value in unexported:
+                    f.write('%s="%s"\n' % (key, value.replace('"', '\\"')))
+
+        if (
+            temp_dir is not None
+            and not (emerge_from == "ebuild" and phase == "setup")
+            and os.path.exists(os.path.join(temp_dir, "environment"))
+        ):
+            filter_calling_env = True
 
         environ_whitelist = self._environ_whitelist
         for x, myvalue in self.iteritems():
@@ -3275,10 +3302,6 @@ def environ(self):
         # Filtered by IUSE and implicit IUSE.
         mydict["USE"] = self.get("PORTAGE_USE", "")
 
-        # Don't export AA to the ebuild environment in EAPIs that forbid it
-        if not eapi_exports_AA(eapi):
-            mydict.pop("AA", None)
-
         if not eapi_exports_merge_type(eapi):
             mydict.pop("MERGE_TYPE", None)