From f990ee961a75791adfdea2f5efb35017a51a310e Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Zbigniew=20J=C4=99drzejewski-Szmek?= <zbyszek@in.waw.pl>
Date: Tue, 8 Mar 2022 10:08:05 +0100
Subject: [PATCH] basic/env-file: make load-env-file deduplicate entries with
 the same key

We generally assume parsing like the shell would do it, so the last value
should win when there are repeats.

(cherry picked from commit 25407ad2a785d10b1aadff0c99829ea0cf51082b)

Related: #2082131
---
 src/basic/env-file.c     | 31 ++++++++++++++++++++-----------
 src/test/test-env-file.c |  5 +++++
 src/test/test-os-util.c  |  3 +--
 3 files changed, 26 insertions(+), 13 deletions(-)

diff --git a/src/basic/env-file.c b/src/basic/env-file.c
index 599b73bc22..0353f3f2a0 100644
--- a/src/basic/env-file.c
+++ b/src/basic/env-file.c
@@ -415,30 +415,39 @@ static int load_env_file_push_pairs(
                 const char *key, char *value,
                 void *userdata,
                 int *n_pushed) {
-        char ***m = userdata;
+        char ***m = ASSERT_PTR(userdata);
+        bool added = false;
         int r;
 
         r = check_utf8ness_and_warn(filename, line, key, value);
         if (r < 0)
                 return r;
 
+        /* Check if the key is present */
+        for (char **t = *m; t && *t; t += 2)
+                if (streq(t[0], key)) {
+                        if (value)
+                                r = free_and_replace(t[1], value);
+                        else
+                                r = free_and_strdup(t+1, "");
+                        goto finish;
+                }
+
         r = strv_extend(m, key);
         if (r < 0)
                 return -ENOMEM;
 
-        if (!value) {
-                r = strv_extend(m, "");
-                if (r < 0)
-                        return -ENOMEM;
-        } else {
+        if (value)
                 r = strv_push(m, value);
-                if (r < 0)
-                        return r;
-        }
+        else
+                r = strv_extend(m, "");
+        added = true;
+ finish:
+        if (r < 0)
+                return r;
 
-        if (n_pushed)
+        if (n_pushed && added)
                 (*n_pushed)++;
-
         return 0;
 }
 
diff --git a/src/test/test-env-file.c b/src/test/test-env-file.c
index 886a8e4bc8..461a0f0810 100644
--- a/src/test/test-env-file.c
+++ b/src/test/test-env-file.c
@@ -9,7 +9,12 @@
 #include "tests.h"
 #include "tmpfile-util.h"
 
+/* In case of repeating keys, later entries win. */
+
 #define env_file_1                              \
+        "a=a\n"                                 \
+        "a=b\n"                                 \
+        "a=b\n"                                 \
         "a=a\n"                                 \
         "b=b\\\n"                               \
         "c\n"                                   \
diff --git a/src/test/test-os-util.c b/src/test/test-os-util.c
index 5f82748783..d6336c53e9 100644
--- a/src/test/test-os-util.c
+++ b/src/test/test-os-util.c
@@ -67,8 +67,7 @@ TEST(load_os_release_pairs) {
 
         _cleanup_strv_free_ char **pairs = NULL;
         assert_se(load_os_release_pairs(NULL, &pairs) == 0);
-        assert_se(strv_equal(pairs, STRV_MAKE("ID", "ignored", // FIXME
-                                              "ID", "the-id",
+        assert_se(strv_equal(pairs, STRV_MAKE("ID", "the-id",
                                               "NAME", "the-name")));
 
         assert_se(unsetenv("SYSTEMD_OS_RELEASE") == 0);