Re: [PATCH v3] linux-user,bsd-user: preserve incoming order of environment variables in the target

[Warner Losh]

On Wed, Mar 29, 2023, 9:00 AM Andreas Schwab <schwab@suse.de> wrote:

Do not reverse the order of environment variables in the target environ
array relative to the incoming environ order.  Some testsuites depend on a
specific order, even though it is not defined by any standard.

Signed-off-by: Andreas Schwab <schwab@suse.de>
---
 bsd-user/main.c   | 10 +++++++++-
 linux-user/main.c | 10 +++++++++-
 2 files changed, 18 insertions(+), 2 deletions(-)

Reviewed-by: Warner Losh <imp@bsdimp.com>

diff --git a/bsd-user/main.c b/bsd-user/main.c
index 89f225dead..eff834e8d8 100644
--- a/bsd-user/main.c
+++ b/bsd-user/main.c
@@ -298,8 +298,16 @@ int main(int argc, char **argv)

     envlist = envlist_create();

-    /* add current environment into the list */
+    /*
+     * add current environment into the list
+     * envlist_setenv adds to the front of the list; to preserve environ
+     * order add from back to front
+     */
     for (wrk = environ; *wrk != NULL; wrk++) {
+        continue;
+    }
+    while (wrk != environ) {
+        wrk--;
         (void) envlist_setenv(envlist, *wrk);
     }

diff --git a/linux-user/main.c b/linux-user/main.c
index 4b18461969..f0173ceefa 100644
--- a/linux-user/main.c
+++ b/linux-user/main.c
@@ -690,8 +690,16 @@ int main(int argc, char **argv, char **envp)

     envlist = envlist_create();

-    /* add current environment into the list */
+    /*
+     * add current environment into the list
+     * envlist_setenv adds to the front of the list; to preserve environ
+     * order add from back to front
+     */
     for (wrk = environ; *wrk != NULL; wrk++) {
+        continue;
+    }
+    while (wrk != environ) {
+        wrk--;
         (void) envlist_setenv(envlist, *wrk);
     }

--
2.40.0


--
Andreas Schwab, SUSE Labs, schwab@suse.de
GPG Key fingerprint = 0196 BAD8 1CE9 1970 F4BE  1748 E4D4 88E3 0EEA B9D7
"And now for something completely different."