From: Simon Kuenzer <simon@unikraft.io>
Date: Fri, 24 Feb 2023 00:45:52 +0000 (+0100)
Subject: lib/posix-environ: Variables from kernel command line
X-Git-Tag: RELEASE-0.13.0~53
X-Git-Url: http://xenbits.xensource.com/gitweb?a=commitdiff_plain;h=fefaa0591880d69770a869cbc06f85b38872dc61;p=unikraft%2Funikraft.git

lib/posix-environ: Variables from kernel command line

Introduces the ability to populate additional environment variables via the
kernel command line.

Checkpatch-Ignore: SPACING
Signed-off-by: Simon Kuenzer <simon@unikraft.io>
Reviewed-by: Delia Pavel <delia_maria.pavel@stud.acs.upb.ro>
Approved-by: Razvan Deaconescu <razvand@unikraft.io>
Tested-by: Unikraft CI <monkey@unikraft.io>
GitHub-Closes: #868
---

diff --git a/lib/posix-environ/Config.uk b/lib/posix-environ/Config.uk
index 9073afdd3..a1ab2af66 100644
--- a/lib/posix-environ/Config.uk
+++ b/lib/posix-environ/Config.uk
@@ -104,4 +104,17 @@ if LIBPOSIX_ENVIRON
 		bool
 		default y if LIBPOSIX_ENVIRON_ENVP15 != ""
 	endmenu
+
+	config LIBPOSIX_ENVIRON_LIBPARAM
+	bool "Parse kernel command line arguments"
+	default n
+	select LIBUKLIBPARAM
+
+	config LIBPOSIX_ENVIRON_LIBPARAM_MAXCOUNT
+	int "Additional reserved entries for vars from command line"
+	default 8
+	depends on LIBPOSIX_ENVIRON_LIBPARAM
+	help
+		This number defines the maximum number of variables that
+		can be handed over with the kernel command line.
 endif
diff --git a/lib/posix-environ/Makefile.uk b/lib/posix-environ/Makefile.uk
index 9e36517fa..6128e2476 100644
--- a/lib/posix-environ/Makefile.uk
+++ b/lib/posix-environ/Makefile.uk
@@ -1,4 +1,6 @@
 $(eval $(call addlib_s,libposix_environ,$(CONFIG_LIBPOSIX_ENVIRON)))
+# Register to uklibparam, sets "env" as parameter prefix (env.*)
+$(eval $(call uk_libparam_libprefix_set,libposix_environ,env))
 
 LIBPOSIX_ENVIRON_SRCS-y += $(LIBPOSIX_ENVIRON_BASE)/setenv.c
 LIBPOSIX_ENVIRON_SRCS-y += $(LIBPOSIX_ENVIRON_BASE)/unsetenv.c
diff --git a/lib/posix-environ/environ.c b/lib/posix-environ/environ.c
index d555683bb..4a76acdeb 100644
--- a/lib/posix-environ/environ.c
+++ b/lib/posix-environ/environ.c
@@ -3,10 +3,66 @@
  * Licensed under the BSD-3-Clause License (the "License").
  * You may not use this file except in compliance with the License.
  */
+#include <uk/libparam.h>
 #include <uk/essentials.h>
 #include "environ.h"
 
-static char *__ct_env[] = {
+/*
+ * Size the array
+ */
+static char *__init_env[1 /* null termination */
+#if CONFIG_LIBPOSIX_ENVIRON_ENVP0_NOTEMPTY
+	+ 1
+#endif /* CONFIG_LIBPOSIX_ENVIRON_ENVP0_NOTEMPTY */
+#if CONFIG_LIBPOSIX_ENVIRON_ENVP1_NOTEMPTY
+	+ 1
+#endif /* CONFIG_LIBPOSIX_ENVIRON_ENVP1_NOTEMPTY */
+#if CONFIG_LIBPOSIX_ENVIRON_ENVP2_NOTEMPTY
+	+ 1
+#endif /* CONFIG_LIBPOSIX_ENVIRON_ENVP2_NOTEMPTY */
+#if CONFIG_LIBPOSIX_ENVIRON_ENVP3_NOTEMPTY
+	+ 1
+#endif /* CONFIG_LIBPOSIX_ENVIRON_ENVP3_NOTEMPTY */
+#if CONFIG_LIBPOSIX_ENVIRON_ENVP4_NOTEMPTY
+	+ 1
+#endif /* CONFIG_LIBPOSIX_ENVIRON_ENVP4_NOTEMPTY */
+#if CONFIG_LIBPOSIX_ENVIRON_ENVP5_NOTEMPTY
+	+ 1
+#endif /* CONFIG_LIBPOSIX_ENVIRON_ENVP5_NOTEMPTY */
+#if CONFIG_LIBPOSIX_ENVIRON_ENVP6_NOTEMPTY
+	+ 1
+#endif /* CONFIG_LIBPOSIX_ENVIRON_ENVP6_NOTEMPTY */
+#if CONFIG_LIBPOSIX_ENVIRON_ENVP7_NOTEMPTY
+	+ 1
+#endif /* CONFIG_LIBPOSIX_ENVIRON_ENVP7_NOTEMPTY */
+#if CONFIG_LIBPOSIX_ENVIRON_ENVP8_NOTEMPTY
+	+ 1
+#endif /* CONFIG_LIBPOSIX_ENVIRON_ENVP8_NOTEMPTY */
+#if CONFIG_LIBPOSIX_ENVIRON_ENVP9_NOTEMPTY
+	+ 1
+#endif /* CONFIG_LIBPOSIX_ENVIRON_ENVP9_NOTEMPTY */
+#if CONFIG_LIBPOSIX_ENVIRON_ENVP10_NOTEMPTY
+	+ 1
+#endif /* CONFIG_LIBPOSIX_ENVIRON_ENVP10_NOTEMPTY */
+#if CONFIG_LIBPOSIX_ENVIRON_ENVP11_NOTEMPTY
+	+ 1
+#endif /* CONFIG_LIBPOSIX_ENVIRON_ENVP11_NOTEMPTY */
+#if CONFIG_LIBPOSIX_ENVIRON_ENVP12_NOTEMPTY
+	+ 1
+#endif /* CONFIG_LIBPOSIX_ENVIRON_ENVP12_NOTEMPTY */
+#if CONFIG_LIBPOSIX_ENVIRON_ENVP13_NOTEMPTY
+	+ 1
+#endif /* CONFIG_LIBPOSIX_ENVIRON_ENVP13_NOTEMPTY */
+#if CONFIG_LIBPOSIX_ENVIRON_ENVP14_NOTEMPTY
+	+ 1
+#endif /* CONFIG_LIBPOSIX_ENVIRON_ENVP14_NOTEMPTY */
+#if CONFIG_LIBPOSIX_ENVIRON_ENVP15_NOTEMPTY
+	+ 1
+#endif /* CONFIG_LIBPOSIX_ENVIRON_ENVP15_NOTEMPTY */
+#if CONFIG_LIBPOSIX_ENVIRON_LIBPARAM
+	+ CONFIG_LIBPOSIX_ENVIRON_LIBPARAM_MAXCOUNT
+#endif /* CONFIG_LIBPOSIX_ENVIRON_LIBPARAM */
+	] = {
 #if CONFIG_LIBPOSIX_ENVIRON_ENVP0_NOTEMPTY
 	CONFIG_LIBPOSIX_ENVIRON_ENVP0,
 #endif /* CONFIG_LIBPOSIX_ENVIRON_ENVP0_NOTEMPTY */
@@ -58,4 +114,13 @@ static char *__ct_env[] = {
 	NULL /* termination */
 };
 
-char **__environ = __ct_env;
+#if CONFIG_LIBPOSIX_ENVIRON_LIBPARAM
+UK_LIBPARAM_PARAM_ARR_ALIAS(vars,
+			    &(__init_env[ARRAY_SIZE(__init_env) -
+				CONFIG_LIBPOSIX_ENVIRON_LIBPARAM_MAXCOUNT - 1]),
+			    charp,
+			    CONFIG_LIBPOSIX_ENVIRON_LIBPARAM_MAXCOUNT,
+			    "Environment variables");
+#endif
+
+char **__environ = __init_env;