[PATCH] posix: Move environ helper variables next to environ definition (bug 32541)
Florian Weimer
fweimer@redhat.com
Fri Mar 7 16:32:41 GMT 2025
This helps with statically interposing getenv.
Updates commit 7a61e7f557a97ab597d6fca5e2d1f13f65685c61
("stdlib: Make getenv thread-safe in more cases").
---
posix/environ.c | 4 ++++
stdlib/Makefile | 2 ++
stdlib/getenv.c | 3 ---
stdlib/tst-getenv-static.c | 38 ++++++++++++++++++++++++++++++++++++++
4 files changed, 44 insertions(+), 3 deletions(-)
diff --git a/posix/environ.c b/posix/environ.c
index a0ed0d80ea..924effe3cd 100644
--- a/posix/environ.c
+++ b/posix/environ.c
@@ -2,6 +2,7 @@
#include <unistd.h>
#include <stddef.h>
+#include <stdlib/setenv.h>
/* This must be initialized; we cannot have a weak alias into bss. */
char **__environ = NULL;
@@ -10,3 +11,6 @@ weak_alias (__environ, environ)
/* The SVR4 ABI says `_environ' will be the name to use
in case the user overrides the weak alias `environ'. */
weak_alias (__environ, _environ)
+
+struct environ_array *__environ_array_list;
+environ_counter __environ_counter;
diff --git a/stdlib/Makefile b/stdlib/Makefile
index 1c4fa2382f..c9c8f702a2 100644
--- a/stdlib/Makefile
+++ b/stdlib/Makefile
@@ -282,6 +282,7 @@ tests := \
tst-environ-change-3 \
tst-environ-change-4 \
tst-getenv-signal \
+ tst-getenv-static \
tst-getenv-thread \
tst-getenv-unsetenv \
tst-getrandom \
@@ -377,6 +378,7 @@ tests-internal := \
# tests-internal
tests-static := \
+ tst-getenv-static \
tst-secure-getenv \
# tests-static
diff --git a/stdlib/getenv.c b/stdlib/getenv.c
index 5e7212cca6..1a7b0bfc06 100644
--- a/stdlib/getenv.c
+++ b/stdlib/getenv.c
@@ -20,9 +20,6 @@
#include <string.h>
#include <unistd.h>
-struct environ_array *__environ_array_list;
-environ_counter __environ_counter;
-
char *
getenv (const char *name)
{
diff --git a/stdlib/tst-getenv-static.c b/stdlib/tst-getenv-static.c
new file mode 100644
index 0000000000..f5f484c83a
--- /dev/null
+++ b/stdlib/tst-getenv-static.c
@@ -0,0 +1,38 @@
+/* Static interposition of getenv (bug 32541).
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <https://www.gnu.org/licenses/>. */
+
+#include <stdlib.h>
+#include <support/check.h>
+
+/* Some programs try to interpose getenv for their own use (not
+ glibc's internal use). Make sure that this is possible without
+ introducing linker failures due to duplicate symbols. */
+
+char *
+getenv (const char *ignored)
+{
+ return NULL;
+}
+
+static int
+do_test (void)
+{
+ TEST_COMPARE_STRING (getenv ("PATH"), NULL);
+ return 0;
+}
+
+#include <support/test-driver.c>
base-commit: 59dc232df277c21239c357e3519682c26e182cd7
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