env: make "env default" selective, check and apply

Change the syntax (user API) for "env default": -f: override write-once variables var... : accept individual variable(s) -a: all (resetting the whole env is NOT the default behavior) Enable variable checking and make changes effective by enabling do_apply argument to himport_r(). Signed-off-by: Gerlando Falauto <gerlando.falauto@keymile.com>

env: make "env default" selective, check and apply
Change the syntax (user API) for "env default": -f: override write-once variables var... : accept individual variable(s) -a: all (resetting the whole env is NOT the default behavior) Enable variable checking and make changes effective by enabling do_apply argument to himport_r(). Signed-off-by: Gerlando Falauto <gerlando.falauto@keymile.com>
Gerlando Falauto · Tom Rini
1 parent 152874b65b
Showing 3 changed files with 64 additions and 7 deletions Side-by-side Diff
common/cmd_nvedit.c
common/env_common.c
include/environment.h
@@ -656,14 +656,41 @@
 	return -1;
 }
  
-static int do_env_default(cmd_tbl_t *cmdtp, int flag,
+static int do_env_default(cmd_tbl_t *cmdtp, int __flag,
 			  int argc, char * const argv[])
 {
-	if (argc != 2 || strcmp(argv[1], "-f") != 0)
-		return CMD_RET_USAGE;
+	int all = 0, flag = 0;
  
-	set_default_env("## Resetting to default environment\n");
-	return 0;
+	debug("Initial value for argc=%d\n", argc);
+	while (--argc > 0 && **++argv == '-') {
+		char *arg = *argv;
+
+		while (*++arg) {
+			switch (*arg) {
+			case 'a':		/* default all */
+				all = 1;
+				break;
+			case 'f':		/* force */
+				flag |= H_FORCE;
+				break;
+			default:
+				return cmd_usage(cmdtp);
+			}
+		}
+	}
+	debug("Final value for argc=%d\n", argc);
+	if (all && (argc == 0)) {
+		/* Reset the whole environment */
+		set_default_env("## Resetting to default environment\n");
+		return 0;
+	}
+	if (!all && (argc > 0)) {
+		/* Reset individual variables */
+		set_default_vars(argc, argv);
+		return 0;
+	}
+
+	return cmd_usage(cmdtp);
 }
  
 static int do_env_delete(cmd_tbl_t *cmdtp, int flag,
@@ -994,7 +1021,8 @@
 #if defined(CONFIG_CMD_ASKENV)
 	"ask name [message] [size] - ask for environment variable\nenv "
 #endif
-	"default -f - reset default environment\n"
+	"default [-f] -a - [forcibly] reset default environment\n"
+	"env default [-f] var [...] - [forcibly] reset variable(s) to their default values\n"
 #if defined(CONFIG_CMD_EDITENV)
 	"env edit name - edit environment variable\n"
 #endif
@@ -180,6 +180,11 @@
  
 void set_default_env(const char *s)
 {
+	/*
+	 * By default, do not apply changes as they will eventually
+	 * be applied by someone else
+	 */
+	int do_apply = 0;
 	if (sizeof(default_environment) > ENV_SIZE) {
 		puts("*** Error - default environment is too large\n\n");
 		return;
@@ -191,6 +196,14 @@
 				"using default environment\n\n",
 				s + 1);
 		} else {
+			/*
+			 * This set_to_default was explicitly asked for
+			 * by the user, as opposed to being a recovery
+			 * mechanism.  Therefore we check every single
+			 * variable and apply changes to the system
+			 * right away (e.g. baudrate, console).
+			 */
+			do_apply = 1;
 			puts(s);
 		}
 	} else {
  
@@ -199,10 +212,23 @@
  
 	if (himport_r(&env_htab, (char *)default_environment,
 			sizeof(default_environment), '\0', 0,
-			0, NULL, 0 /* do_apply */) == 0)
+			0, NULL, do_apply) == 0)
 		error("Environment import failed: errno = %d\n", errno);
  
 	gd->flags |= GD_FLG_ENV_READY;
+}
+
+
+/* [re]set individual variables to their value in the default environment */
+int set_default_vars(int nvars, char * const vars[])
+{
+	/*
+	 * Special use-case: import from default environment
+	 * (and use \0 as a separator)
+	 */
+	return himport_r(&env_htab, (const char *)default_environment,
+				sizeof(default_environment), '\0', H_NOCLEAR,
+				nvars, vars, 1 /* do_apply */);
 }
  
 /*
@@ -181,6 +181,9 @@
 /* [re]set to the default environment */
 void set_default_env(const char *s);
  
+/* [re]set individual variables to their value in the default environment */
+int set_default_vars(int nvars, char * const vars[]);
+
 /* Import from binary representation into hash table */
 int env_import(const char *buf, int check);
...	...	@@ -656,14 +656,41 @@
656	656	return -1;
657	657	}
658	658
659		-static int do_env_default(cmd_tbl_t *cmdtp, int flag,
	659	+static int do_env_default(cmd_tbl_t *cmdtp, int __flag,
660	660	int argc, char * const argv[])
661	661	{
662		- if (argc != 2 \|\| strcmp(argv[1], "-f") != 0)
663		- return CMD_RET_USAGE;
	662	+ int all = 0, flag = 0;
664	663
665		- set_default_env("## Resetting to default environment\n");
666		- return 0;
	664	+ debug("Initial value for argc=%d\n", argc);
	665	+ while (--argc > 0 && **++argv == '-') {
	666	+ char arg = argv;
	667	+
	668	+ while (*++arg) {
	669	+ switch (*arg) {
	670	+ case 'a': /* default all */
	671	+ all = 1;
	672	+ break;
	673	+ case 'f': /* force */
	674	+ flag \|= H_FORCE;
	675	+ break;
	676	+ default:
	677	+ return cmd_usage(cmdtp);
	678	+ }
	679	+ }
	680	+ }
	681	+ debug("Final value for argc=%d\n", argc);
	682	+ if (all && (argc == 0)) {
	683	+ /* Reset the whole environment */
	684	+ set_default_env("## Resetting to default environment\n");
	685	+ return 0;
	686	+ }
	687	+ if (!all && (argc > 0)) {
	688	+ /* Reset individual variables */
	689	+ set_default_vars(argc, argv);
	690	+ return 0;
	691	+ }
	692	+
	693	+ return cmd_usage(cmdtp);
667	694	}
668	695
669	696	static int do_env_delete(cmd_tbl_t *cmdtp, int flag,
...	...	@@ -994,7 +1021,8 @@
994	1021	#if defined(CONFIG_CMD_ASKENV)
995	1022	"ask name [message] [size] - ask for environment variable\nenv "
996	1023	#endif
997		- "default -f - reset default environment\n"
	1024	+ "default [-f] -a - [forcibly] reset default environment\n"
	1025	+ "env default [-f] var [...] - [forcibly] reset variable(s) to their default values\n"
998	1026	#if defined(CONFIG_CMD_EDITENV)
999	1027	"env edit name - edit environment variable\n"
1000	1028	#endif
...	...	@@ -180,6 +180,11 @@
180	180
181	181	void set_default_env(const char *s)
182	182	{
	183	+ /*
	184	+ * By default, do not apply changes as they will eventually
	185	+ * be applied by someone else
	186	+ */
	187	+ int do_apply = 0;
183	188	if (sizeof(default_environment) > ENV_SIZE) {
184	189	puts("*** Error - default environment is too large\n\n");
185	190	return;
...	...	@@ -191,6 +196,14 @@
191	196	"using default environment\n\n",
192	197	s + 1);
193	198	} else {
	199	+ /*
	200	+ * This set_to_default was explicitly asked for
	201	+ * by the user, as opposed to being a recovery
	202	+ * mechanism. Therefore we check every single
	203	+ * variable and apply changes to the system
	204	+ * right away (e.g. baudrate, console).
	205	+ */
	206	+ do_apply = 1;
194	207	puts(s);
195	208	}
196	209	} else {
197	210
...	...	@@ -199,10 +212,23 @@
199	212
200	213	if (himport_r(&env_htab, (char *)default_environment,
201	214	sizeof(default_environment), '\0', 0,
202		- 0, NULL, 0 /* do_apply */) == 0)
	215	+ 0, NULL, do_apply) == 0)
203	216	error("Environment import failed: errno = %d\n", errno);
204	217
205	218	gd->flags \|= GD_FLG_ENV_READY;
	219	+}
	220	+
	221	+
	222	+/* [re]set individual variables to their value in the default environment */
	223	+int set_default_vars(int nvars, char * const vars[])
	224	+{
	225	+ /*
	226	+ * Special use-case: import from default environment
	227	+ * (and use \0 as a separator)
	228	+ */
	229	+ return himport_r(&env_htab, (const char *)default_environment,
	230	+ sizeof(default_environment), '\0', H_NOCLEAR,
	231	+ nvars, vars, 1 /* do_apply */);
206	232	}
207	233
208	234	/*
...	...	@@ -181,6 +181,9 @@
181	181	/* [re]set to the default environment */
182	182	void set_default_env(const char *s);
183	183
	184	+/* [re]set individual variables to their value in the default environment */
	185	+int set_default_vars(int nvars, char * const vars[]);
	186	+
184	187	/* Import from binary representation into hash table */
185	188	int env_import(const char *buf, int check);
186	189