From 4ab3d29ff03c0508f47846875d9310cbc5b8cd0f Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Zbigniew=20J=C4=99drzejewski-Szmek?= <zbyszek@in.waw.pl>
Date: Sat, 7 Aug 2021 10:16:19 +0200
Subject: [PATCH] Add implicit sentinel to strv_env_merge()

Just to make it a tiny bit nicer to use.

---
 src/basic/env-util.c     | 40 ++++++++++++++++++++++++++--------------
 src/basic/env-util.h     |  3 ++-
 src/core/dbus-execute.c  |  4 ++--
 src/core/execute.c       |  5 ++---
 src/core/locale-setup.c  |  2 +-
 src/core/manager.c       |  6 +++---
 src/core/service.c       |  2 +-
 src/notify/notify.c      |  2 +-
 src/nspawn/nspawn.c      | 20 ++++++++++----------
 src/run/run.c            |  2 +-
 src/test/test-env-util.c |  2 +-
 11 files changed, 50 insertions(+), 38 deletions(-)

diff --git a/src/basic/env-util.c b/src/basic/env-util.c
index 81b1e3f10e..0c30ddc277 100644
--- a/src/basic/env-util.c
+++ b/src/basic/env-util.c
@@ -183,39 +183,51 @@ static int env_append(char **r, char ***k, char **a) {
         return 0;
 }
 
-char **strv_env_merge(size_t n_lists, ...) {
-        _cleanup_strv_free_ char **ret = NULL;
-        size_t n = 0;
-        char **l, **k;
+char** _strv_env_merge(char **first, ...) {
+        _cleanup_strv_free_ char **merged = NULL;
+        char **k;
         va_list ap;
 
         /* Merges an arbitrary number of environment sets */
 
-        va_start(ap, n_lists);
-        for (size_t i = 0; i < n_lists; i++) {
+        size_t n = strv_length(first);
+
+        va_start(ap, first);
+        for (;;) {
+                char **l;
+
                 l = va_arg(ap, char**);
+                if (l == POINTER_MAX)
+                        break;
+
                 n += strv_length(l);
         }
         va_end(ap);
 
-        ret = new(char*, n+1);
-        if (!ret)
+        k = merged = new(char*, n + 1);
+        if (!merged)
                 return NULL;
+        merged[0] = NULL;
 
-        *ret = NULL;
-        k = ret;
+        if (env_append(merged, &k, first) < 0)
+                return NULL;
+
+        va_start(ap, first);
+        for (;;) {
+                char **l;
 
-        va_start(ap, n_lists);
-        for (size_t i = 0; i < n_lists; i++) {
                 l = va_arg(ap, char**);
-                if (env_append(ret, &k, l) < 0) {
+                if (l == POINTER_MAX)
+                        break;
+
+                if (env_append(merged, &k, l) < 0) {
                         va_end(ap);
                         return NULL;
                 }
         }
         va_end(ap);
 
-        return TAKE_PTR(ret);
+        return TAKE_PTR(merged);
 }
 
 static bool env_match(const char *t, const char *pattern) {
diff --git a/src/basic/env-util.h b/src/basic/env-util.h
index 1fbe7e4270..18d10ebab8 100644
--- a/src/basic/env-util.h
+++ b/src/basic/env-util.h
@@ -39,7 +39,8 @@ char **strv_env_clean_with_callback(char **l, void (*invalid_callback)(const cha
 bool strv_env_name_is_valid(char **l);
 bool strv_env_name_or_assignment_is_valid(char **l);
 
-char **strv_env_merge(size_t n_lists, ...);
+char** _strv_env_merge(char **first, ...);
+#define strv_env_merge(first, ...) _strv_env_merge(first, __VA_ARGS__, POINTER_MAX)
 char **strv_env_delete(char **x, size_t n_lists, ...); /* New copy */
 
 char **strv_env_unset(char **l, const char *p); /* In place ... */
diff --git a/src/core/dbus-execute.c b/src/core/dbus-execute.c
index f6783e924a..5ea97b9194 100644
--- a/src/core/dbus-execute.c
+++ b/src/core/dbus-execute.c
@@ -2888,7 +2888,7 @@ int bus_exec_context_set_transient_property(
                                 if (!joined)
                                         return -ENOMEM;
 
-                                e = strv_env_merge(2, c->environment, l);
+                                e = strv_env_merge(c->environment, l);
                                 if (!e)
                                         return -ENOMEM;
 
@@ -2922,7 +2922,7 @@ int bus_exec_context_set_transient_property(
                                 if (!joined)
                                         return -ENOMEM;
 
-                                e = strv_env_merge(2, c->unset_environment, l);
+                                e = strv_env_merge(c->unset_environment, l);
                                 if (!e)
                                         return -ENOMEM;
 
diff --git a/src/core/execute.c b/src/core/execute.c
index 4608956259..5bee44ac7b 100644
--- a/src/core/execute.c
+++ b/src/core/execute.c
@@ -4158,8 +4158,7 @@ static int exec_child(
                 return log_oom();
         }
 
-        accum_env = strv_env_merge(5,
-                                   params->environment,
+        accum_env = strv_env_merge(params->environment,
                                    our_env,
                                    pass_env,
                                    context->environment,
@@ -5214,7 +5213,7 @@ static int exec_context_load_environment(const Unit *unit, const ExecContext *c,
                         else {
                                 char **m;
 
-                                m = strv_env_merge(2, r, p);
+                                m = strv_env_merge(r, p);
                                 strv_free(r);
                                 strv_free(p);
                                 if (!m)
diff --git a/src/core/locale-setup.c b/src/core/locale-setup.c
index 64761ddb11..59ddb9c487 100644
--- a/src/core/locale-setup.c
+++ b/src/core/locale-setup.c
@@ -85,7 +85,7 @@ int locale_setup(char ***environment) {
         else {
                 char **merged;
 
-                merged = strv_env_merge(2, *environment, add);
+                merged = strv_env_merge(*environment, add);
                 if (!merged)
                         return -ENOMEM;
 
diff --git a/src/core/manager.c b/src/core/manager.c
index 24dfe9fc06..d76b7b2b16 100644
--- a/src/core/manager.c
+++ b/src/core/manager.c
@@ -3672,7 +3672,7 @@ int manager_transient_environment_add(Manager *m, char **plus) {
         if (strv_isempty(plus))
                 return 0;
 
-        a = strv_env_merge(2, m->transient_environment, plus);
+        a = strv_env_merge(m->transient_environment, plus);
         if (!a)
                 return log_oom();
 
@@ -3704,7 +3704,7 @@ int manager_client_environment_modify(
         }
 
         if (!strv_isempty(plus)) {
-                b = strv_env_merge(2, l, plus);
+                b = strv_env_merge(l, plus);
                 if (!b) {
                         strv_free(a);
                         return -ENOMEM;
@@ -3731,7 +3731,7 @@ int manager_get_effective_environment(Manager *m, char ***ret) {
         assert(m);
         assert(ret);
 
-        l = strv_env_merge(2, m->transient_environment, m->client_environment);
+        l = strv_env_merge(m->transient_environment, m->client_environment);
         if (!l)
                 return -ENOMEM;
 
diff --git a/src/core/service.c b/src/core/service.c
index ddcfeb8523..4115db0a30 100644
--- a/src/core/service.c
+++ b/src/core/service.c
@@ -1546,7 +1546,7 @@ static int service_spawn(
         if (r < 0)
                 return r;
 
-        final_env = strv_env_merge(2, exec_params.environment, our_env, NULL);
+        final_env = strv_env_merge(exec_params.environment, our_env);
         if (!final_env)
                 return -ENOMEM;
 
diff --git a/src/notify/notify.c b/src/notify/notify.c
index 49d5f3ec92..b468a5bc44 100644
--- a/src/notify/notify.c
+++ b/src/notify/notify.c
@@ -232,7 +232,7 @@ static int run(int argc, char* argv[]) {
 
         our_env[i++] = NULL;
 
-        final_env = strv_env_merge(2, our_env, argv + optind);
+        final_env = strv_env_merge(our_env, argv + optind);
         if (!final_env)
                 return log_oom();
 
diff --git a/src/nspawn/nspawn.c b/src/nspawn/nspawn.c
index d75cce408e..cf89b27dfa 100644
--- a/src/nspawn/nspawn.c
+++ b/src/nspawn/nspawn.c
@@ -3189,8 +3189,8 @@ static int inner_child(
         _cleanup_free_ char *home = NULL;
         char as_uuid[ID128_UUID_STRING_MAX];
         size_t n_env = 1;
-        const char *envp[] = {
-                "PATH=" DEFAULT_PATH_COMPAT,
+        char *envp[] = {
+                (char*) "PATH=" DEFAULT_PATH_COMPAT,
                 NULL, /* container */
                 NULL, /* TERM */
                 NULL, /* HOME */
@@ -3426,17 +3426,17 @@ static int inner_child(
                 n_env++;
 
         if (home || !uid_is_valid(arg_uid) || arg_uid == 0)
-                if (asprintf((char**)(envp + n_env++), "HOME=%s", home ?: "/root") < 0)
+                if (asprintf(envp + n_env++, "HOME=%s", home ?: "/root") < 0)
                         return log_oom();
 
         if (arg_user || !uid_is_valid(arg_uid) || arg_uid == 0)
-                if (asprintf((char**)(envp + n_env++), "USER=%s", arg_user ?: "root") < 0 ||
-                    asprintf((char**)(envp + n_env++), "LOGNAME=%s", arg_user ? arg_user : "root") < 0)
+                if (asprintf(envp + n_env++, "USER=%s", arg_user ?: "root") < 0 ||
+                    asprintf(envp + n_env++, "LOGNAME=%s", arg_user ? arg_user : "root") < 0)
                         return log_oom();
 
         assert(!sd_id128_is_null(arg_uuid));
 
-        if (asprintf((char**)(envp + n_env++), "container_uuid=%s", id128_to_uuid_string(arg_uuid, as_uuid)) < 0)
+        if (asprintf(envp + n_env++, "container_uuid=%s", id128_to_uuid_string(arg_uuid, as_uuid)) < 0)
                 return log_oom();
 
         if (fdset_size(fds) > 0) {
@@ -3444,11 +3444,11 @@ static int inner_child(
                 if (r < 0)
                         return log_error_errno(r, "Failed to unset O_CLOEXEC for file descriptors.");
 
-                if ((asprintf((char **)(envp + n_env++), "LISTEN_FDS=%u", fdset_size(fds)) < 0) ||
-                    (asprintf((char **)(envp + n_env++), "LISTEN_PID=1") < 0))
+                if ((asprintf(envp + n_env++, "LISTEN_FDS=%u", fdset_size(fds)) < 0) ||
+                    (asprintf(envp + n_env++, "LISTEN_PID=1") < 0))
                         return log_oom();
         }
-        if (asprintf((char **)(envp + n_env++), "NOTIFY_SOCKET=%s", NSPAWN_NOTIFY_SOCKET_PATH) < 0)
+        if (asprintf(envp + n_env++, "NOTIFY_SOCKET=%s", NSPAWN_NOTIFY_SOCKET_PATH) < 0)
                 return log_oom();
 
         if (arg_n_credentials > 0) {
@@ -3458,7 +3458,7 @@ static int inner_child(
                 n_env++;
         }
 
-        env_use = strv_env_merge(3, envp, os_release_pairs, arg_setenv);
+        env_use = strv_env_merge(envp, os_release_pairs, arg_setenv);
         if (!env_use)
                 return log_oom();
 
diff --git a/src/run/run.c b/src/run/run.c
index 0be974f03a..993f1bc4f4 100644
--- a/src/run/run.c
+++ b/src/run/run.c
@@ -1526,7 +1526,7 @@ static int start_transient_scope(sd_bus *bus) {
                         return log_error_errno(errno, "Failed to change UID to " UID_FMT ": %m", uid);
         }
 
-        env = strv_env_merge(3, environ, user_env, arg_environment);
+        env = strv_env_merge(environ, user_env, arg_environment);
         if (!env)
                 return log_oom();
 
diff --git a/src/test/test-env-util.c b/src/test/test-env-util.c
index ed4580e4af..5bf130ed86 100644
--- a/src/test/test-env-util.c
+++ b/src/test/test-env-util.c
@@ -81,7 +81,7 @@ static void test_strv_env_merge(void) {
         b = strv_new("FOO=KKK", "FOO=", "PIEP=", "SCHLUMPF=SMURFF", "NANANANA=YES");
         assert_se(b);
 
-        r = strv_env_merge(2, a, b);
+        r = strv_env_merge(a, b);
         assert_se(r);
         assert_se(streq(r[0], "FOO="));
         assert_se(streq(r[1], "WALDO="));
-- 
2.33.0

