env: reworking + default/import individual vars

index fa99c44..10b9552 100644
@@ -194,32 +194,23 @@ static int do_env_grep (cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[
 #endif
 
 /*
- * Set a new environment variable,
- * or replace or delete an existing one.
+ * Performs consistency checking before setting, replacing,
+ * or deleting an environment variable, then (if successful)
+ * apply the changes to internals so to make them effective.
+ * Code for this function was taken out of _do_env_set(),
+ * which now calls it.
+ * Also called as a callback function by himport_ex().
+ * Returns 0 in case of success, 1 in case of failure.
+ * When (flag & H_FORCE) is set, force overwriting of
+ * write-once variables.
  */
 
-int _do_env_set (int flag, int argc, char * const argv[])
+int env_check_apply(const char *name, const char *oldval,
+		    const char *newval, int flag)
 {
 	bd_t  *bd = gd->bd;
-	int   i, len;
+	int   i;
 	int   console = -1;
-	char  *name, *value, *s;
-	ENTRY e, *ep;
-
-	name = argv[1];
-
-	if (strchr(name, '=')) {
-		printf("## Error: illegal character '=' in variable name \"%s\"\n", name);
-		return 1;
-	}
-
-	env_id++;
-	/*
-	 * search if variable with this name already exists
-	 */
-	e.key = name;
-	e.data = NULL;
-	hsearch_r(e, FIND, &ep, &env_htab);
 
 	/* Check for console redirection */
 	if (strcmp(name, "stdin") == 0)

@@ -230,22 +221,23 @@ int _do_env_set (int flag, int argc, char * const argv[])
 		console = stderr;
 
 	if (console != -1) {
-		if (argc < 3) {		/* Cannot delete it! */
+		if ((newval == NULL) || (*newval == '\0')) {
+			/* We cannot delete stdin/stdout/stderr */
 			printf("Can't delete \"%s\"\n", name);
 			return 1;
 		}
 
 #ifdef CONFIG_CONSOLE_MUX
-		i = iomux_doenv(console, argv[2]);
+		i = iomux_doenv(console, newval);
 		if (i)
 			return i;
 #else
 		/* Try assigning specified device */
-		if (console_assign(console, argv[2]) < 0)
+		if (console_assign(console, newval) < 0)
 			return 1;
 
 #ifdef CONFIG_SERIAL_MULTI
-		if (serial_assign(argv[2]) < 0)
+		if (serial_assign(newval) < 0)
 			return 1;
 #endif
 #endif /* CONFIG_CONSOLE_MUX */

@@ -255,23 +247,29 @@ int _do_env_set (int flag, int argc, char * const argv[])
 	 * Some variables like "ethaddr" and "serial#" can be set only
 	 * once and cannot be deleted; also, "ver" is readonly.
 	 */
-	if (ep) {		/* variable exists */
+	if ((oldval != NULL) /* variable exists */
+	 && ((flag & H_FORCE) == 0)) { /* and we are not forced */
 #ifndef CONFIG_ENV_OVERWRITE
 		if ((strcmp(name, "serial#") == 0) ||
 		    ((strcmp(name, "ethaddr") == 0)
 #if defined(CONFIG_OVERWRITE_ETHADDR_ONCE) && defined(CONFIG_ETHADDR)
-		     && (strcmp(ep->data, MK_STR(CONFIG_ETHADDR)) != 0)
+		     && (strcmp(oldval, MK_STR(CONFIG_ETHADDR)) != 0)
 #endif	/* CONFIG_OVERWRITE_ETHADDR_ONCE && CONFIG_ETHADDR */
 		    ) ) {
 			printf("Can't overwrite \"%s\"\n", name);
 			return 1;
 		}
 #endif
+	}
+	/* if variable exists... */
+	if ((oldval != NULL)
+	/* or we are in a scratched-out environment */
+	|| ((flag & H_NOCLEAR) == 0)) {
 		/*
 		 * Switch to new baudrate if new baudrate is supported
 		 */
 		if (strcmp(name, "baudrate") == 0) {
-			int baudrate = simple_strtoul(argv[2], NULL, 10);
+			int baudrate = simple_strtoul(newval, NULL, 10);
 			int i;
 			for (i = 0; i < N_BAUDRATES; ++i) {
 				if (baudrate == baudrate_table[i])

@@ -282,6 +280,10 @@ int _do_env_set (int flag, int argc, char * const argv[])
 					baudrate);
 				return 1;
 			}
+			if (gd->baudrate == baudrate) {
+				/* If unchanged, we just say it's OK */
+				return 0;
+			}
 			printf ("## Switch baudrate to %d bps and press ENTER ...\n",
 				baudrate);
 			udelay(50000);

@@ -299,6 +301,72 @@ int _do_env_set (int flag, int argc, char * const argv[])
 		}
 	}
 
+	/*
+	 * Some variables should be updated when the corresponding
+	 * entry in the environment is changed
+	 */
+
+	if (strcmp(name, "ipaddr") == 0) {
+		const char *s = newval;	/* always use only one arg */
+		char *e;
+		unsigned long addr;
+		bd->bi_ip_addr = 0;
+		for (addr = 0, i = 0; i < 4; ++i) {
+			ulong val = s ? simple_strtoul(s, &e, 10) : 0;
+			addr <<= 8;
+			addr  |= (val & 0xFF);
+			if (s)
+				s = (*e) ? e+1 : e;
+		}
+		bd->bi_ip_addr = htonl(addr);
+		return 0;
+	} else if (strcmp(newval, "loadaddr") == 0) {
+		load_addr = simple_strtoul(newval, NULL, 16);
+		return 0;
+	}
+#if defined(CONFIG_CMD_NET)
+	else if (strcmp(newval, "bootfile") == 0) {
+		copy_filename(BootFile, newval, sizeof(BootFile));
+		return 0;
+	}
+#endif
+	return 0;
+}
+
+/*
+ * Set a new environment variable,
+ * or replace or delete an existing one.
+*/
+int _do_env_set(int flag, int argc, char * const argv[])
+{
+	int   i, len;
+	char  *name, *value, *s;
+	ENTRY e, *ep;
+
+	name = argv[1];
+	value = argv[2];
+
+	if (strchr(name, '=')) {
+		printf("## Error: illegal character '='"
+		       "in variable name \"%s\"\n", name);
+		return 1;
+	}
+
+	env_id++;
+	/*
+	 * search if variable with this name already exists
+	 */
+	e.key = name;
+	e.data = NULL;
+	hsearch_r(e, FIND, &ep, &env_htab);
+
+	/* Perform requested checks. Notice how since we are overwriting
+	 * a single variable, we need to set H_NOCLEAR */
+	if (env_check_apply(name, ep ? ep->data : NULL, value, H_NOCLEAR)) {
+		debug("check function did not approve, refusing\n");
+		return 1;
+	}
+
 	/* Delete only ? */
 	if ((argc < 3) || argv[2] == NULL) {
 		int rc = hdelete_r(name, &env_htab);

@@ -336,34 +404,6 @@ int _do_env_set (int flag, int argc, char * const argv[])
 		return 1;
 	}
 
-	/*
-	 * Some variables should be updated when the corresponding
-	 * entry in the environment is changed
-	 */
-
-	if (strcmp(name, "ipaddr") == 0) {
-		char *s = argv[2];	/* always use only one arg */
-		char *e;
-		unsigned long addr;
-		bd->bi_ip_addr = 0;
-		for (addr = 0, i = 0; i < 4; ++i) {
-			ulong val = s ? simple_strtoul(s, &e, 10) : 0;
-			addr <<= 8;
-			addr  |= (val & 0xFF);
-			if (s) s = (*e) ? e+1 : e;
-		}
-		bd->bi_ip_addr = htonl(addr);
-		return 0;
-	} else if (strcmp(argv[1], "loadaddr") == 0) {
-		load_addr = simple_strtoul(argv[2], NULL, 16);
-		return 0;
-	}
-#if defined(CONFIG_CMD_NET)
-	else if (strcmp(argv[1], "bootfile") == 0) {
-		copy_filename(BootFile, argv[2], sizeof(BootFile));
-		return 0;
-	}
-#endif
 	return 0;
 }
 

index c7e9bea..db607e1 100644
@@ -172,6 +172,9 @@ const uchar *env_get_addr (int index)
 
 void set_default_env(const char *s)
 {
+	/* By default, do not apply changes as they will eventually
+	 * be applied by someone else */
+	apply_cb apply_function = NULL;
 	if (sizeof(default_environment) > ENV_SIZE) {
 		puts("*** Error - default environment is too large\n\n");
 		return;

@@ -183,14 +186,22 @@ void set_default_env(const char *s)
 				"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 chack every single
+			 * variable and apply changes to the system
+			 * right away (e.g. baudrate, console).
+			 */
+			apply_function = env_check_apply;
 			puts(s);
 		}
 	} else {
 		puts("Using default environment\n\n");
 	}
 
-	if (himport_r(&env_htab, (char *)default_environment,
-		    sizeof(default_environment), '\0', 0) == 0) {
+	if (himport_ex(&env_htab, (char *)default_environment,
+		    sizeof(default_environment), '\0', 0,
+		      0, NULL, apply_function) == 0) {
 		error("Environment import failed: errno = %d\n", errno);
 	}
 	gd->flags |= GD_FLG_ENV_READY;

index 6394a96..cd98f91 100644
@@ -174,6 +174,13 @@ void set_default_env(const char *s);
 /* Import from binary representation into hash table */
 int env_import(const char *buf, int check);
 
+/*
+ * Check if variable "name" can be changed from oldval to newval,
+ * and if so, apply the changes (e.g. baudrate)
+ */
+int env_check_apply(const char *name, const char *oldval,
+		    const char *newval, int flag);
+
 #endif
 
 #endif	/* _ENVIRONMENT_H_ */

index b4edd43..4ac7171 100644
@@ -46,6 +46,11 @@ typedef struct entry {
 /* Opaque type for internal use.  */
 struct _ENTRY;
 
+/* Callback function to be called for checking whether the given change may
+ * be applied or not. Must return 0 for approval, 1 for denial. */
+typedef int (*apply_cb)(const char *name, const char *oldval,
+			const char *newval, int flag);
+
 /*
  * Family of hash table handling functions.  The functions also
  * have reentrant counterparts ending with _r.  The non-reentrant

@@ -97,7 +102,15 @@ extern int himport_r(struct hsearch_data *__htab,
 		     const char *__env, size_t __size, const char __sep,
 		     int __flag);
 
+extern int himport_ex(struct hsearch_data *__htab,
+		     const char *__env, size_t __size, const char __sep,
+		     int __flag,
+		     int __argc, char * const __argv[],
+		     apply_cb apply);
+
+
 /* Flags for himport_r() */
 #define	H_NOCLEAR	1	/* do not clear hash table before importing */
+#define H_FORCE		2	/* overwrite read-only/write-once variables */
 
 #endif /* search.h */

72 lines not on this page · raw message

index 10b9552..905d3be 100644
@@ -369,7 +369,7 @@ int _do_env_set(int flag, int argc, char * const argv[])
 
 	/* Delete only ? */
 	if ((argc < 3) || argv[2] == NULL) {
-		int rc = hdelete_r(name, &env_htab);
+		int rc = hdelete_r(name, &env_htab, NULL);
 		return !rc;
 	}
 

index 4ac7171..cc620bd 100644
@@ -68,7 +68,8 @@ struct hsearch_data {
 extern int hcreate_r(size_t __nel, struct hsearch_data *__htab);
 
 /* Destroy current internal hashing table.  */
-extern void hdestroy_r(struct hsearch_data *__htab);
+extern void hdestroy_r(struct hsearch_data *__htab,
+		       apply_cb apply);
 
 /*
  * Search for entry matching ITEM.key in internal hash table.  If

@@ -93,7 +94,8 @@ extern int hstrstr_r(const char *__match, int __last_idx, ENTRY ** __retval,
 		    struct hsearch_data *__htab);
 
 /* Search and delete entry matching ITEM.key in internal hash table. */
-extern int hdelete_r(const char *__key, struct hsearch_data *__htab);
+extern int hdelete_r(const char *__key, struct hsearch_data *__htab,
+		     apply_cb apply);
 
 extern ssize_t hexport_r(struct hsearch_data *__htab,
 		     const char __sep, char **__resp, size_t __size);

index a2c268f..d84882f 100644
@@ -142,7 +142,8 @@ int hcreate_r(size_t nel, struct hsearch_data *htab)
  * be freed and the local static variable can be marked as not used.
  */
 
-void hdestroy_r(struct hsearch_data *htab)
+void hdestroy_r(struct hsearch_data *htab,
+		int(*apply)(const char *, const char *, const char *, int))
 {
 	int i;
 

@@ -156,7 +157,10 @@ void hdestroy_r(struct hsearch_data *htab)
 	for (i = 1; i <= htab->size; ++i) {
 		if (htab->table[i].used > 0) {
 			ENTRY *ep = &htab->table[i].entry;
-
+			if (apply != NULL) {
+				/* deletion is always forced */
+				apply(ep->key, ep->data, NULL, H_FORCE);
+			}
 			free((void *)ep->key);
 			free(ep->data);
 		}

@@ -401,7 +405,8 @@ int hsearch_r(ENTRY item, ACTION action, ENTRY ** retval,
  * do that.
  */
 
-int hdelete_r(const char *key, struct hsearch_data *htab)
+int hdelete_r(const char *key, struct hsearch_data *htab,
+	      int(*apply)(const char *, const char *, const char *, int))
 {
 	ENTRY e, *ep;
 	int idx;

@@ -417,7 +422,8 @@ int hdelete_r(const char *key, struct hsearch_data *htab)
 
 	/* free used ENTRY */
 	debug("hdelete: DELETING key \"%s\"\n", key);
-
+	if (apply != NULL)
+		apply(ep->key, ep->data, NULL, H_FORCE);
 	free((void *)ep->key);
 	free(ep->data);
 	htab->table[idx].used = -1;

@@ -679,7 +685,7 @@ int himport_ex(struct hsearch_data *htab,
 		debug("Destroy Hash Table: %p table = %p\n", htab,
 		       htab->table);
 		if (htab->table)
-			hdestroy_r(htab);
+			hdestroy_r(htab, apply);
 	}
 
 	/*

@@ -745,7 +751,7 @@ int himport_ex(struct hsearch_data *htab,
 			if (!process_var(name, nvars, vars))
 				continue;
 
-			if (hdelete_r(name, htab) == 0)
+			if (hdelete_r(name, htab, apply) == 0)
 				debug("DELETE ERROR ##############################\n");
 
 			continue;

55 lines not on this page · raw message

index db607e1..af28d47 100644
@@ -207,6 +207,20 @@ void set_default_env(const char *s)
 	gd->flags |= GD_FLG_ENV_READY;
 }
 
+#ifdef CONFIG_CMD_DEFAULTENV_VARS
+
+/* [re]set individual variables to their value in the default environment */
+int env_default_vars(int nvars, char * const vars[])
+{
+	/* Special use-case: import from default environment
+	   (and use \0 as a separator) */
+	return himport_ex(&env_htab, (const char *)default_environment,
+			  sizeof(default_environment), '\0', H_NOCLEAR,
+			  nvars, vars, env_check_apply);
+}
+
+#endif /* CONFIG_CMD_DEFAULTENV_VARS */
+
 /*
  * Check if CRC is valid and (if yes) import the environment.
  * Note that "buf" may or may not be aligned.

index 9716f9c..e728eae 100644
@@ -25,6 +25,7 @@
 #define CONFIG_CMD_CDP		/* Cisco Discovery Protocol	*/
 #define CONFIG_CMD_CONSOLE	/* coninfo			*/
 #define CONFIG_CMD_DATE		/* support for RTC, date/time...*/
+#define CONFIG_CMD_DEFAULTENV_VARS /* default individ variables */
 #define CONFIG_CMD_DHCP		/* DHCP Support			*/
 #define CONFIG_CMD_DIAG		/* Diagnostics			*/
 #define CONFIG_CMD_DISPLAY	/* Display support		*/

index cd98f91..b9201d3 100644
@@ -171,6 +171,11 @@ void env_crc_update (void);
 /* [re]set to the default environment */
 void set_default_env(const char *s);
 
+#ifdef CONFIG_CMD_DEFAULTENV_VARS
+/* [re]set individual variables to their value in the default environment */
+int env_default_vars(int nvars, char * const vars[]);
+#endif
+
 /* Import from binary representation into hash table */
 int env_import(const char *buf, int check);
 

index 07cd062..0984a53 100644
@@ -831,15 +831,19 @@ sep_err:
  *	size:	length of input data; if missing, proper '\0'
  *		termination is mandatory
  */
-static int do_env_import(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
+#define MAX_NVARS 16
+static int do_env_import(cmd_tbl_t *cmdtp, int __flag, int argc,
+			 char * const argv[])
 {
 	char	*cmd, *addr;
 	char	sep = '\n';
 	int	chk = 0;
 	int	fmt = 0;
-	int	del = 0;
+	int	flag = H_NOCLEAR;
 	size_t	size;
-
+	char	*vars[MAX_NVARS];
+	int	nvars = 0;
+	char	*s;
 	cmd = *argv;
 
 	while (--argc > 0 && **++argv == '-') {

@@ -863,7 +867,27 @@ static int do_env_import(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv
 				sep = '\n';
 				break;
 			case 'd':
-				del = 1;
+				flag &= ~H_NOCLEAR;
+				break;
+			case 'f':
+				flag |= H_FORCE;
+				break;
+			case 'n':
+				s = *++argv;
+				argc--;
+				do {
+					if (nvars >= MAX_NVARS) {
+						printf("Cannot import more "
+						       "than %d variables at a"
+						       " time!", MAX_NVARS);
+						return 1;
+					}
+					vars[nvars++] = strsep(&s, ",");
+					debug("Considering variable %s\n",
+					      vars[nvars-1]);
+				} while (s);
+				debug("Importing a total of %d variables\n",
+				      nvars);
 				break;
 			default:
 				return cmd_usage(cmdtp);

@@ -914,7 +938,8 @@ static int do_env_import(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv
 		addr = (char *)ep->data;
 	}
 
-	if (himport_r(&env_htab, addr, size, sep, del ? 0 : H_NOCLEAR) == 0) {
+	if (himport_ex(&env_htab, addr, size, sep, flag,
+		       nvars, vars, NULL) == 0) {
 		error("Environment import failed: errno = %d\n", errno);
 		return 1;
 	}

index 5507922..2dd4eba 100644
@@ -465,40 +465,50 @@ int do_env_ask(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 {
 	extern char console_buffer[CONFIG_SYS_CBSIZE];
 	char message[CONFIG_SYS_CBSIZE];
-	int size = CONFIG_SYS_CBSIZE - 1;
-	int i, len, pos;
+	int i, len, pos, size;
 	char *local_args[4];
+	char *endptr;
 
 	local_args[0] = argv[0];
 	local_args[1] = argv[1];
 	local_args[2] = NULL;
 	local_args[3] = NULL;
 
-	/* Check the syntax */
-	switch (argc) {
-	case 1:
+	/*
+	 * Check the syntax:
+	 *
+	 * env_ask envname [message1 ...] [size]
+	 */
+	if (argc == 1)
 		return cmd_usage(cmdtp);
 
-	case 2:		/* env_ask envname */
-		sprintf(message, "Please enter '%s':", argv[1]);
-		break;
-
-	case 3:		/* env_ask envname size */
-		sprintf(message, "Please enter '%s':", argv[1]);
-		size = simple_strtoul(argv[2], NULL, 10);
-		break;
-
-	default:	/* env_ask envname message1 ... messagen size */
-		for (i = 2, pos = 0; i < argc - 1; i++) {
+	/*
+	 * We test the last argument if it can be converted
+	 * into a decimal number.  If yes, we assume it's
+	 * the size.  Otherwise we echo it as part of the
+	 * message.
+	 */
+	i = simple_strtoul(argv[argc - 1], &endptr, 10);
+	if (*endptr != '\0') {			/* no size */
+		size = CONFIG_SYS_CBSIZE - 1;
+	} else {				/* size given */
+		size = i;
+		--argc;
+	}
+	
+	if (argc <= 2) {
+		sprintf(message, "Please enter '%s': ", argv[1]);
+	} else {
+		/* env_ask envname message1 ... messagen [size] */
+		for (i = 2, pos = 0; i < argc; i++) {
 			if (pos)
 				message[pos++] = ' ';
 
 			strcpy(message+pos, argv[i]);
 			pos += strlen(argv[i]);
 		}
+		message[pos++] = ' ';
 		message[pos] = '\0';
-		size = simple_strtoul(argv[argc - 1], NULL, 10);
-		break;
 	}
 
 	if (size >= CONFIG_SYS_CBSIZE)

new file mode 100644
index 0000000..4b41a4b
@@ -0,0 +1,100 @@
+/*
+ * Copyright (c) 2004-2005 Sergey Lyubka <[email protected]>
+ * All rights reserved
+ *
+ * "THE BEER-WARE LICENSE" (Revision 42):
+ * Sergey Lyubka wrote this file.  As long as you retain this notice you
+ * can do whatever you want with this stuff. If we meet some day, and you think
+ * this stuff is worth it, you can buy me a beer in return.
+ */
+
+/*
+ * Downloaded Sat Nov  5 17:42:08 CET 2011 at
+ * http://slre.sourceforge.net/1.0/slre.h
+ */
+
+/*
+ * This is a regular expression library that implements a subset of Perl RE.
+ * Please refer to http://slre.sourceforge.net for detailed description.
+ *
+ * Usage example (parsing HTTP request):
+ *
+ * struct slre	slre;
+ * struct cap	captures[4 + 1];  // Number of braket pairs + 1
+ * ...
+ *
+ * slre_compile(&slre,"^(GET|POST) (\S+) HTTP/(\S+?)\r\n");
+ *
+ * if (slre_match(&slre, buf, len, captures)) {
+ *	printf("Request line length: %d\n", captures[0].len);
+ *	printf("Method: %.*s\n", captures[1].len, captures[1].ptr);
+ *	printf("URI: %.*s\n", captures[2].len, captures[2].ptr);
+ * }
+ *
+ * Supported syntax:
+ *	^		Match beginning of a buffer
+ *	$		Match end of a buffer
+ *	()		Grouping and substring capturing
+ *	[...]		Match any character from set
+ *	[^...]		Match any character but ones from set
+ *	\s		Match whitespace
+ *	\S		Match non-whitespace
+ *	\d		Match decimal digit
+ *	\r		Match carriage return
+ *	\n		Match newline
+ *	+		Match one or more times (greedy)
+ *	+?		Match one or more times (non-greedy)
+ *	*		Match zero or more times (greedy)
+ *	*?		Match zero or more times (non-greedy)
+ *	?		Match zero or once
+ *	\xDD		Match byte with hex value 0xDD
+ *	\meta		Match one of the meta character: ^$().[*+?\
+ */
+
+#ifndef SLRE_HEADER_DEFINED
+#define	SLRE_HEADER_DEFINED
+
+/*
+ * Compiled regular expression
+ */
+struct slre {
+	unsigned char	code[256];
+	unsigned char	data[256];
+	int		code_size;
+	int		data_size;
+	int		num_caps;	/* Number of bracket pairs	*/
+	int		anchored;	/* Must match from string start	*/
+	const char	*err_str;	/* Error string			*/
+};
+
+/*
+ * Captured substring
+ */
+struct cap {
+	const char	*ptr;		/* Pointer to the substring	*/
+	int		len;		/* Substring length		*/
+};
+
+/*
+ * Compile regular expression. If success, 1 is returned.
+ * If error, 0 is returned and slre.err_str points to the error message.
+ */
+int slre_compile(struct slre *, const char *re);
+
+/*
+ * Return 1 if match, 0 if no match.
+ * If `captured_substrings' array is not NULL, then it is filled with the
+ * values of captured substrings. captured_substrings[0] element is always
+ * a full matched substring. The round bracket captures start from
+ * captured_substrings[1].
+ * It is assumed that the size of captured_substrings array is enough to
+ * hold all captures. The caller function must make sure it is! So, the
+ * array_size = number_of_round_bracket_pairs + 1
+ */
+int slre_match(const struct slre *, const char *buf, int buf_len,
+	struct cap *captured_substrings);
+
+#ifdef SLRE_TEST
+void slre_dump(const struct slre *r, FILE *fp);
+#endif /* SLRE_TEST */
+#endif /* SLRE_HEADER_DEFINED */

709 lines not on this page · raw message

index 2dd4eba..4307d27 100644
@@ -164,6 +164,288 @@ int do_env_print (cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 	return rcode;
 }
 
+#ifdef CONFIG_CMD_REGEX
+
+/*
+ * memstr - Find the first substring in memory
+ * @s1: The string to be searched
+ * @s2: The string to search for
+ *
+ * Similar to and based on strstr(),
+ * but strings do not need to be NUL terminated.
+ */
+static char *memstr(const char *s1, int l1, const char *s2, int l2)
+{
+	if (!l2)
+		return (char *) s1;
+
+	while (l1 >= l2) {
+		l1--;
+		if (!memcmp(s1, s2, l2))
+			return (char *) s1;
+		s1++;
+	}
+	return NULL;
+}
+
+static char *substitute(char *string,	/* string buffer */
+			int *slen,	/* current string length */
+			int ssize,	/* string bufer size */
+			const char *old,/* old (replaced) string */
+			int olen,	/* length of old string */
+			const char *new,/* new (replacement) string */
+			int nlen)	/* length of new string */
+{
+	char *p = memstr(string, *slen, old, olen);
+
+	if (p == NULL)
+		return NULL;
+
+	debug("## Match at pos %ld: match len %d, subst len %d\n",
+		(long)(p - string), olen, nlen);
+
+	/* make sure replacement matches */
+	if (*slen + nlen - olen > ssize) {
+		printf("## error: substitution buffer overflow\n");
+		return NULL;
+	}
+
+	/* move tail if needed */
+	if (olen != nlen) {
+		int tail, len;
+
+		len = (olen > nlen) ? olen : nlen;
+
+		tail = ssize - (p + len - string);
+
+		debug("## tail len %d\n", tail);
+
+		memmove(p + nlen, p + olen, tail);
+	}
+
+	/* insert substitue */
+	memcpy(p, new, nlen);
+
+	*slen += nlen - olen;
+
+	return p + nlen;
+}
+
+#include "slre.h"
+
+#define	SLRE_BUFSZ	16384
+#define	SLRE_PATSZ	4096
+
+/*
+ * Perform regex operations on a environment variable
+ *
+ * Returns 0 in case of error, or length of printed string
+ */
+static int env_regex(const char *name, const char *regexp, const char *subst,
+			int global)
+{
+	ENTRY e, *ep;
+	struct slre slre;
+	struct cap caps[32];
+	char data[SLRE_BUFSZ];
+	char *datap = data;
+	int res, len, nlen, loop;
+
+	if (name == NULL)
+		return 0;
+
+	if (slre_compile(&slre, regexp) == 0) {
+		printf("Error compiling regex: %s\n", slre.err_str);
+		return 1;
+	}
+
+	e.key = name;
+	e.data = NULL;
+	hsearch_r(e, FIND, &ep, &env_htab);
+	if (ep == NULL) {
+		printf("## Error: \"%s\" not defined\n", name);
+		return 1;
+	}
+
+	debug("REGEX on %s=%s\n", ep->key, ep->data);
+	debug("REGEX=\"%s\", SUBST=\"%s\", GLOBAL=%d\n",
+		regexp, subst ? subst : "<NULL>", global);
+
+	len = strlen(ep->data);
+	if (len + 1 > SLRE_BUFSZ) {
+		printf("## error: substitution buffer overflow\n");
+		return 1;
+	}
+
+	strcpy(data, ep->data);
+
+	if (subst == NULL)
+		nlen = 0;
+	else
+		nlen = strlen(subst);
+
+	for (loop = 0; ;loop++) {
+		char nbuf[SLRE_PATSZ];
+		const char *old;;
+		char *np;
+		int i, olen;
+
+		(void) memset(caps, 0, sizeof(caps));
+
+		res = slre_match(&slre, datap, len, caps);
+
+		debug("Result: %d\n", res);
+
+		for (i = 0; i < 20; i++) {
+			if (caps[i].len > 0) {
+				debug("Substring %d: [%.*s]\n", i,
+					caps[i].len, caps[i].ptr);
+			}
+		}
+
+		if (res == 0) {
+			if (loop == 0) {
+				printf("%s: No match\n", ep->key);
+				return 1;
+			} else {
+				break;
+			}
+		}
+
+		debug("## MATCH ## %s\n", data);
+
+		if (subst == NULL) {
+			printf("%s=%s\n", ep->key, ep->data);
+			return 0;
+		}
+
+		old = caps[0].ptr;
+		olen = caps[0].len;
+
+		if (nlen + 1 >= SLRE_PATSZ) {
+			printf("## error: pattern buffer overflow\n");
+			return 1;
+		}
+		strcpy(nbuf, subst);
+
+		debug("## SUBST(1) ## %s\n", nbuf);
+
+		/*
+		 * Handle back references
+		 *
+		 * Support for \0 ... \9, where \0 is the
+		 * whole matched pattern (similar to &).
+		 *
+		 * Implementation is a bit simpleminded as
+		 * backrefs are substituted sequentially, one
+		 * by one.  This will lead to somewhat
+		 * unexpected results if the replacement
+		 * strings contain any \N strings then then
+		 * may get substitued, too.  We accept this
+		 * restriction for the sake of simplicity.
+		 */
+		for (i = 0; i < 10; ++i) {
+			char backref[2] = {
+				'\\',
+				'0',
+			};
+
+			if (caps[i].len == 0)
+				break;
+
+			backref[1] += i;
+
+			debug("## BACKREF %d: replace \"%.*s\" by \"%.*s\" in \"%s\"\n",
+				i,
+				2, backref,
+				caps[i].len, caps[i].ptr,
+				nbuf);
+
+			for (np = nbuf;;) {
+				char *p = memstr(np, nlen,
+						backref, 2);
+
+				if (p == NULL)
+					break;
+
+				np = substitute(np, &nlen,
+					SLRE_PATSZ,
+					backref, 2,
+					caps[i].ptr, caps[i].len);
+
+				if (np == NULL)
+					return 1;
+			}
+		}
+		debug("## SUBST(2) ## %s\n", nbuf);
+
+		datap = substitute(datap, &len, SLRE_BUFSZ,
+				old, olen,
+				nbuf, nlen);
+
+		if (datap == NULL)
+			return 1;
+
+		debug("## REMAINDER: %s\n", datap);
+
+		debug("## RESULT: %s\n", data);
+
+		if (!global)
+			break;
+	}
+	debug("## FINAL (now setenv()) :  %s\n", data);
+	
+	printf("%s=%s\n", ep->key, data);
+
+	return setenv(ep->key, data);
+}
+
+static int do_env_regex(cmd_tbl_t *cmdtp, int flag, int argc,
+			char *const argv[])
+{
+	int i;
+	int rcode = 0;
+	int global = 0;
+	const char *regex, *subst = NULL;
+
+	while (--argc > 0 && **++argv == '-') {
+		char *arg = *argv;
+		while (*++arg) {
+			switch (*arg) {
+			case 'e':
+				/* allow regex starting with '-' */
+				++argv;
+				goto DONE;
+			case 'g':
+				global = 1;
+				break;
+			case 's':
+				if (--argc <= 0)
+					return cmd_usage(cmdtp);
+				subst = *++argv;
+				goto NXTARG;
+			default:
+				return cmd_usage(cmdtp);
+			}
+		}
+NXTARG:		;
+	}
+DONE:
+	if (argc < 2)
+		return cmd_usage(cmdtp);
+
+	regex = argv[0];
+
+	/* process selected env vars */
+	for (i = 1; i < argc; ++i) {
+		if (env_regex(argv[i], regex, subst, global) != 0)
+			rcode = 1;
+	}
+
+	return rcode;
+}
+#endif
+
 #ifdef CONFIG_CMD_GREPENV
 static int do_env_grep (cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 {

@@ -1022,6 +1304,9 @@ static cmd_tbl_t cmd_env_sub[] = {
 	U_BOOT_CMD_MKENT(import, 5, 0, do_env_import, "", ""),
 #endif
 	U_BOOT_CMD_MKENT(print, CONFIG_SYS_MAXARGS, 1, do_env_print, "", ""),
+#if defined(CONFIG_CMD_REGEX)
+	U_BOOT_CMD_MKENT(regex, CONFIG_SYS_MAXARGS, 1, do_env_regex, "", ""),
+#endif
 #if defined(CONFIG_CMD_RUN)
 	U_BOOT_CMD_MKENT(run, CONFIG_SYS_MAXARGS, 1, do_run, "", ""),
 #endif

@@ -1076,6 +1361,9 @@ U_BOOT_CMD(
 #endif
 	"env import [-d] [-t | -b | -c] addr [size] - import environment\n"
 	"env print [name ...] - print environment\n"
+#ifdef CONFIG_CMD_REGEX
+	"env regex [-g] [-s subst] regex name [...] - search and substitute regular expression\n"
+#endif
 #if defined(CONFIG_CMD_RUN)
 	"env run var [...] - run commands in an environment variable\n"
 #endif

index 7633f0c..5f30f86 100644
@@ -325,41 +325,50 @@ static int do_env_set(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 int do_env_ask(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 {
 	char message[CONFIG_SYS_CBSIZE];
-	int size = CONFIG_SYS_CBSIZE - 1;
-	int i, len, pos;
+	int i, len, pos, size;
 	char *local_args[4];
+	char *endptr;
 
 	local_args[0] = argv[0];
 	local_args[1] = argv[1];
 	local_args[2] = NULL;
 	local_args[3] = NULL;
 
-	/* Check the syntax */
-	switch (argc) {
-	case 1:
+	/*
+	 * Check the syntax:
+	 *
+	 * env_ask envname [message1 ...] [size]
+	 */
+	if (argc == 1)
 		return CMD_RET_USAGE;
 
-	case 2:		/* env_ask envname */
-		sprintf(message, "Please enter '%s':", argv[1]);
-		break;
-
-	case 3:		/* env_ask envname size */
-		sprintf(message, "Please enter '%s':", argv[1]);
-		size = simple_strtoul(argv[2], NULL, 10);
-		break;
-
-	default:	/* env_ask envname message1 ... messagen size */
-		for (i = 2, pos = 0; i < argc - 1; i++) {
+	/*
+	 * We test the last argument if it can be converted
+	 * into a decimal number.  If yes, we assume it's
+	 * the size.  Otherwise we echo it as part of the
+	 * message.
+	 */
+	i = simple_strtoul(argv[argc - 1], &endptr, 10);
+	if (*endptr != '\0') {			/* no size */
+		size = CONFIG_SYS_CBSIZE - 1;
+	} else {				/* size given */
+		size = i;
+		--argc;
+	}
+	
+	if (argc <= 2) {
+		sprintf(message, "Please enter '%s': ", argv[1]);
+	} else {
+		/* env_ask envname message1 ... messagen [size] */
+		for (i = 2, pos = 0; i < argc; i++) {
 			if (pos)
 				message[pos++] = ' ';
 
 			strcpy(message + pos, argv[i]);
 			pos += strlen(argv[i]);
 		}
-
+		message[pos++] = ' ';
 		message[pos] = '\0';
-		size = simple_strtoul(argv[argc - 1], NULL, 10);
-		break;
 	}
 
 	if (size >= CONFIG_SYS_CBSIZE)

@@ -1168,14 +1177,7 @@ U_BOOT_CMD(
 	askenv,	CONFIG_SYS_MAXARGS,	1,	do_env_ask,
 	"get environment variables from stdin",
 	"name [message] [size]\n"
-	"    - get environment variable 'name' from stdin (max 'size' chars)\n"
-	"askenv name\n"
-	"    - get environment variable 'name' from stdin\n"
-	"askenv name size\n"
-	"    - get environment variable 'name' from stdin (max 'size' chars)\n"
-	"askenv name [message] size\n"
-	"    - display 'message' string and get environment variable 'name'"
-	"from stdin (max 'size' chars)"
+	"    - get environment variable 'name' from stdin (max 'size' chars)"
 );
 #endif
 

index 947d6c4..5c84795 100644
@@ -1,5 +1,5 @@
 /*
- * (C) Copyright 2000-2010
+ * (C) Copyright 2000-2013
  * Wolfgang Denk, DENX Software Engineering, wd at denx.de.
  *
  * (C) Copyright 2001 Sysgo Real-Time Solutions, GmbH <www.elinos.com>

@@ -871,7 +871,9 @@ NXTARG:		;
 	argv++;
 
 	if (sep) {		/* export as text file */
-		len = hexport_r(&env_htab, sep, 0, &addr, size, argc, argv);
+		len = hexport_r(&env_htab, sep,
+				H_MATCH_KEY | H_MATCH_IDENT,
+				&addr, size, argc, argv);
 		if (len < 0) {
 			error("Cannot export environment: errno = %d\n", errno);
 			return 1;

@@ -889,7 +891,9 @@ NXTARG:		;
 	else			/* export as raw binary data */
 		res = addr;
 
-	len = hexport_r(&env_htab, '\0', 0, &res, ENV_SIZE, argc, argv);
+	len = hexport_r(&env_htab, '\0',
+			H_MATCH_KEY | H_MATCH_IDENT, 
+			&res, ENV_SIZE, argc, argv);
 	if (len < 0) {
 		error("Cannot export environment: errno = %d\n", errno);
 		return 1;

index 13d3be6..9d9abd6 100644
@@ -22,7 +22,7 @@
 /*
  * Based on code from uClibc-0.9.30.3
  * Extensions for use within U-Boot
- * Copyright (C) 2010 Wolfgang Denk <[email protected]>
+ * Copyright (C) 2010-2013 Wolfgang Denk <[email protected]>
  */
 
 #ifndef _SEARCH_H

@@ -131,5 +131,11 @@ extern int hwalk_r(struct hsearch_data *__htab, int (*callback)(ENTRY *));
 #define H_FORCE		(1 << 1) /* overwrite read-only/write-once variables */
 #define H_INTERACTIVE	(1 << 2) /* indicate that an import is user directed */
 #define H_HIDE_DOT	(1 << 3) /* don't print env vars that begin with '.' */
+#define H_MATCH_KEY	(1 << 4) /* search/grep key  = variable names	     */
+#define H_MATCH_DATA	(1 << 5) /* search/grep data = variable values	     */
+#define H_MATCH_BOTH	(H_MATCH_KEY | H_MATCH_DATA) /* search/grep both     */
+#define H_MATCH_IDENT	(1 << 6) /* search for indentical strings	     */
+#define H_MATCH_SUBSTR  (1 << 7) /* search for substring matches	     */
+#define H_MATCH_METHOD	(H_MATCH_IDENT | H_MATCH_SUBSTR)
 
 #endif /* search.h */

index 07ebfb2..1d18d15 100644
@@ -2,7 +2,7 @@
  * This implementation is based on code from uClibc-0.9.30.3 but was
  * modified and extended for use within U-Boot.
  *
- * Copyright (C) 2010 Wolfgang Denk <[email protected]>
+ * Copyright (C) 2010-2013 Wolfgang Denk <[email protected]>
  *
  * Original license header:
  *

@@ -563,6 +563,28 @@ static int cmpkey(const void *p1, const void *p2)
 	return (strcmp(e1->key, e2->key));
 }
 
+static int match_strings(ENTRY *ep, int flag,
+		 int argc, char * const argv[])
+{
+	int arg;
+
+	for (arg = 0; arg < argc; ++arg) {
+		if (flag & H_MATCH_KEY) {
+			switch (flag & H_MATCH_METHOD) {
+			case H_MATCH_IDENT:
+				if (strcmp(argv[arg], ep->key) == 0) 
+					return 1;
+				break;
+			default:
+				printf("## ERROR: unsupported match method: 0x%02x\n",
+					flag & H_MATCH_METHOD);
+				break;
+			}
+		}
+	}
+	return 0;
+}
+
 ssize_t hexport_r(struct hsearch_data *htab, const char sep, int flag,
 		 char **resp, size_t size,
 		 int argc, char * const argv[])

@@ -589,14 +611,8 @@ ssize_t hexport_r(struct hsearch_data *htab, const char sep, int flag,
 
 		if (htab->table[i].used > 0) {
 			ENTRY *ep = &htab->table[i].entry;
-			int arg, found = 0;
+			int found = match_strings(ep, flag, argc, argv);
 
-			for (arg = 0; arg < argc; ++arg) {
-				if (strcmp(argv[arg], ep->key) == 0) {
-					found = 1;
-					break;
-				}
-			}
 			if ((argc > 0) && (found == 0))
 				continue;
 

index 5c84795..40d9f7a 100644
@@ -162,31 +162,25 @@ static int do_env_print(cmd_tbl_t *cmdtp, int flag, int argc,
 static int do_env_grep(cmd_tbl_t *cmdtp, int flag,
 		       int argc, char * const argv[])
 {
-	ENTRY *match;
-	unsigned char matched[env_htab.size / 8];
-	int rcode = 1, arg = 1, idx;
+	char *res = NULL;
+	int len;
 
 	if (argc < 2)
 		return CMD_RET_USAGE;
 
-	memset(matched, 0, env_htab.size / 8);
+	len = hexport_r(&env_htab, '\n',
+			flag | H_MATCH_BOTH | H_MATCH_SUBSTR,
+			&res, 0, argc, argv);
 
-	while (arg <= argc) {
-		idx = 0;
-		while ((idx = hstrstr_r(argv[arg], idx, &match, &env_htab))) {
-			if (!(matched[idx / 8] & (1 << (idx & 7)))) {
-				puts(match->key);
-				puts("=");
-				puts(match->data);
-				puts("\n");
-			}
-			matched[idx / 8] |= 1 << (idx & 7);
-			rcode = 0;
-		}
-		arg++;
+	if (len > 0) {
+		puts(res);
+		free(res);
 	}
 
-	return rcode;
+	if (len < 2)
+		return 1;
+
+	return 0;
 }
 #endif
 #endif /* CONFIG_SPL_BUILD */

index 9d9abd6..d06a201 100644
@@ -98,12 +98,6 @@ extern int hsearch_r(ENTRY __item, ACTION __action, ENTRY ** __retval,
  */
 extern int hmatch_r(const char *__match, int __last_idx, ENTRY ** __retval,
 		    struct hsearch_data *__htab);
-/*
- * Search for an entry whose key or data contains `MATCH'.  Otherwise,
- * Same semantics as hsearch_r().
- */
-extern int hstrstr_r(const char *__match, int __last_idx, ENTRY ** __retval,
-		    struct hsearch_data *__htab);
 
 /* Search and delete entry matching ITEM.key in internal hash table. */
 extern int hdelete_r(const char *__key, struct hsearch_data *__htab,

87 lines not on this page · raw message

index 40d9f7a..441bf40 100644
@@ -163,13 +163,39 @@ static int do_env_grep(cmd_tbl_t *cmdtp, int flag,
 		       int argc, char * const argv[])
 {
 	char *res = NULL;
-	int len;
+	int len, grep_flags;
 
 	if (argc < 2)
 		return CMD_RET_USAGE;
 
+	grep_flags = H_MATCH_BOTH;
+
+	while (argc > 1 && **(argv + 1) == '-') {
+		char *arg = *++argv;
+
+		--argc;
+		while (*++arg) {
+			switch (*arg) {
+			case 'n':		/* grep for name */
+				grep_flags = H_MATCH_KEY;
+				break;
+			case 'v':		/* grep for value */
+				grep_flags = H_MATCH_DATA;
+				break;
+			case 'b':		/* grep for both */
+				grep_flags = H_MATCH_BOTH;
+				break;
+			case '-':
+				goto DONE;
+			default:
+				return CMD_RET_USAGE;
+			}
+		}
+	}
+
+DONE:
 	len = hexport_r(&env_htab, '\n',
-			flag | H_MATCH_BOTH | H_MATCH_SUBSTR,
+			flag | grep_flags | H_MATCH_SUBSTR,
 			&res, 0, argc, argv);
 
 	if (len > 0) {

@@ -1106,7 +1132,7 @@ static char env_help_text[] =
 	"env flags - print variables that have non-default flags\n"
 #endif
 #if defined(CONFIG_CMD_GREPENV)
-	"env grep string [...] - search environment\n"
+	"env grep [-n | -v | -b] string [...] - search environment\n"
 #endif
 #if defined(CONFIG_CMD_IMPORTENV)
 	"env import [-d] [-t | -b | -c] addr [size] - import environment\n"

@@ -1153,8 +1179,10 @@ U_BOOT_CMD_COMPLETE(
 U_BOOT_CMD_COMPLETE(
 	grepenv, CONFIG_SYS_MAXARGS, 0,  do_env_grep,
 	"search environment variables",
-	"string ...\n"
-	"    - list environment name=value pairs matching 'string'",
+	"[-n | -v | -b] string ...\n"
+	"    - list environment name=value pairs matching 'string'\n"
+	"      \"-n\": search variable names; \"-v\": search values;\n"
+	"      \"-b\": search both names and values (default)",
 	var_complete
 );
 #endif

100 lines not on this page · raw message

724 lines not on this page · raw message

index 441bf40..aecc803 100644
@@ -163,12 +163,13 @@ static int do_env_grep(cmd_tbl_t *cmdtp, int flag,
 		       int argc, char * const argv[])
 {
 	char *res = NULL;
-	int len, grep_flags;
+	int len, grep_how, grep_what;
 
 	if (argc < 2)
 		return CMD_RET_USAGE;
 
-	grep_flags = H_MATCH_BOTH;
+	grep_how  = H_MATCH_SUBSTR;	/* default: substring search	*/
+	grep_what = H_MATCH_BOTH;	/* default: grep names and values */
 
 	while (argc > 1 && **(argv + 1) == '-') {
 		char *arg = *++argv;

@@ -176,14 +177,19 @@ static int do_env_grep(cmd_tbl_t *cmdtp, int flag,
 		--argc;
 		while (*++arg) {
 			switch (*arg) {
+#ifdef CONFIG_REGEX
+			case 'e':		/* use regex matching */
+				grep_how  = H_MATCH_REGEX;
+				break;
+#endif
 			case 'n':		/* grep for name */
-				grep_flags = H_MATCH_KEY;
+				grep_what = H_MATCH_KEY;
 				break;
 			case 'v':		/* grep for value */
-				grep_flags = H_MATCH_DATA;
+				grep_what = H_MATCH_DATA;
 				break;
 			case 'b':		/* grep for both */
-				grep_flags = H_MATCH_BOTH;
+				grep_what = H_MATCH_BOTH;
 				break;
 			case '-':
 				goto DONE;

@@ -195,7 +201,7 @@ static int do_env_grep(cmd_tbl_t *cmdtp, int flag,
 
 DONE:
 	len = hexport_r(&env_htab, '\n',
-			flag | grep_flags | H_MATCH_SUBSTR,
+			flag | grep_what | grep_how,
 			&res, 0, argc, argv);
 
 	if (len > 0) {

@@ -1132,8 +1138,12 @@ static char env_help_text[] =
 	"env flags - print variables that have non-default flags\n"
 #endif
 #if defined(CONFIG_CMD_GREPENV)
+#ifdef CONFIG_REGEX
+	"env grep [-e] [-n | -v | -b] string [...] - search environment\n"
+#else
 	"env grep [-n | -v | -b] string [...] - search environment\n"
 #endif
+#endif
 #if defined(CONFIG_CMD_IMPORTENV)
 	"env import [-d] [-t | -b | -c] addr [size] - import environment\n"
 #endif

@@ -1179,8 +1189,15 @@ U_BOOT_CMD_COMPLETE(
 U_BOOT_CMD_COMPLETE(
 	grepenv, CONFIG_SYS_MAXARGS, 0,  do_env_grep,
 	"search environment variables",
+#ifdef CONFIG_REGEX
+	"[-e] [-n | -v | -b] string ...\n"
+#else
 	"[-n | -v | -b] string ...\n"
+#endif
 	"    - list environment name=value pairs matching 'string'\n"
+#ifdef CONFIG_REGEX
+	"      \"-e\": enable regular expressions;\n"
+#endif
 	"      \"-n\": search variable names; \"-v\": search values;\n"
 	"      \"-b\": search both names and values (default)",
 	var_complete

index d06a201..d9ac8df 100644
@@ -129,7 +129,8 @@ extern int hwalk_r(struct hsearch_data *__htab, int (*callback)(ENTRY *));
 #define H_MATCH_DATA	(1 << 5) /* search/grep data = variable values	     */
 #define H_MATCH_BOTH	(H_MATCH_KEY | H_MATCH_DATA) /* search/grep both     */
 #define H_MATCH_IDENT	(1 << 6) /* search for indentical strings	     */
-#define H_MATCH_SUBSTR  (1 << 7) /* search for substring matches	     */
-#define H_MATCH_METHOD	(H_MATCH_IDENT | H_MATCH_SUBSTR)
+#define H_MATCH_SUBSTR	(1 << 7) /* search for substring matches	     */
+#define H_MATCH_REGEX	(1 << 8) /* search for regular expression matches    */
+#define H_MATCH_METHOD	(H_MATCH_IDENT | H_MATCH_SUBSTR | H_MATCH_REGEX)
 
 #endif /* search.h */

index 8ad56ec..e0d3a19 100644
@@ -57,6 +57,7 @@
 #include <env_callback.h>
 #include <env_flags.h>
 #include <search.h>
+#include <slre.h>
 
 /*
  * [Aho,Sethi,Ullman] Compilers: Principles, Techniques and Tools, 1986

@@ -540,7 +541,7 @@ static int cmpkey(const void *p1, const void *p2)
 	return (strcmp(e1->key, e2->key));
 }
 
-static int match_string(int flag, const char * str, const char * pat)
+static int match_string(int flag, const char *str, const char *pat, void *priv)
 {
 	switch (flag & H_MATCH_METHOD) {
 	case H_MATCH_IDENT:

@@ -551,6 +552,17 @@ static int match_string(int flag, const char * str, const char * pat)
 		if (strstr(str, pat))
 			return 1;
 		break;
+#ifdef CONFIG_REGEX
+	case H_MATCH_REGEX:
+		{
+			struct slre *slrep = (struct slre *)priv;
+			struct cap caps[slrep->num_caps + 2];
+
+			if (slre_match(slrep, str, strlen(str), caps))
+				return 1;
+		}	
+		break;
+#endif
 	default:
 		printf("## ERROR: unsupported match method: 0x%02x\n",
 			flag & H_MATCH_METHOD);

@@ -563,14 +575,25 @@ static int match_entry(ENTRY *ep, int flag,
 		 int argc, char * const argv[])
 {
 	int arg;
+	void *priv = NULL;
 
 	for (arg = 1; arg < argc; ++arg) {
+#ifdef CONFIG_REGEX
+		struct slre slre;
+
+		if (slre_compile(&slre, argv[arg]) == 0) {
+			printf("Error compiling regex: %s\n", slre.err_str);
+			return 0;
+		}
+
+		priv = (void *)&slre;
+#endif
 		if (flag & H_MATCH_KEY) {
-			if (match_string(flag, ep->key, argv[arg]))
+			if (match_string(flag, ep->key, argv[arg], priv))
 				return 1;
 		}
 		if (flag & H_MATCH_DATA) {
-			if (match_string(flag, ep->data, argv[arg]))
+			if (match_string(flag, ep->data, argv[arg], priv))
 				return 1;
 		}
 	}

index 7a38e94..ccd87f4 100644
@@ -56,22 +56,26 @@ static int do_setexpr(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 	ulong value;
 	int w;
 
-	/* Validate arguments */
-	if (argc != 5 && argc != 3)
-		return CMD_RET_USAGE;
-	if (argc == 5 && strlen(argv[3]) != 1)
+	if (argc < 3)
 		return CMD_RET_USAGE;
 
 	w = cmd_get_data_size(argv[0], 4);
 
 	a = get_arg(argv[2], w);
 
+	/* plain assignment: "setexpr name value" */
 	if (argc == 3) {
 		setenv_hex(argv[1], a);
-
 		return 0;
 	}
 
+	/* standard operators: "setexpr name val1 op val2" */
+	if (argc != 5)
+		return CMD_RET_USAGE;
+
+	if (strlen(argv[3]) != 1)
+		return CMD_RET_USAGE;
+
 	b = get_arg(argv[4], w);
 
 	switch (argv[3][0]) {

@@ -117,6 +121,6 @@ U_BOOT_CMD(
 	"      express specified by <op>.  <op> can be &, |, ^, +, -, *, /, %\n"
 	"      size argument is only meaningful if value1 and/or value2 are\n"
 	"      memory addresses (*)\n"
-	"setexpr[.b, .w, .l] name *value\n"
-	"    - load a memory address into a variable"
+	"setexpr[.b, .w, .l] name [*]value\n"
+	"    - load a value into a variable"
 );

index ccd87f4..bfeec29 100644
@@ -1,5 +1,6 @@
 /*
  * Copyright 2008 Freescale Semiconductor, Inc.
+ * Copyright 2013 Wolfgang Denk <[email protected]>
  *
  * See file CREDITS for list of people who contributed to this
  * project.

@@ -50,13 +51,263 @@ static ulong get_arg(char *s, int w)
 	}
 }
 
+#ifdef CONFIG_REGEX
+
+#include <slre.h>
+
+#define SLRE_BUFSZ	16384
+#define SLRE_PATSZ	4096
+
+/*
+ * memstr - Find the first substring in memory
+ * @s1: The string to be searched
+ * @s2: The string to search for
+ *
+ * Similar to and based on strstr(),
+ * but strings do not need to be NUL terminated.
+ */
+static char *memstr(const char *s1, int l1, const char *s2, int l2)
+{
+	if (!l2)
+		return (char *) s1;
+
+	while (l1 >= l2) {
+		l1--;
+		if (!memcmp(s1, s2, l2))
+			return (char *) s1;
+		s1++;
+	}
+	return NULL;
+}
+
+static char *substitute(char *string,	/* string buffer */
+			int *slen,	/* current string length */
+			int ssize,	/* string bufer size */
+			const char *old,/* old (replaced) string */
+			int olen,	/* length of old string */
+			const char *new,/* new (replacement) string */
+			int nlen)	/* length of new string */
+{
+	char *p = memstr(string, *slen, old, olen);
+
+	if (p == NULL)
+		return NULL;
+
+	debug("## Match at pos %ld: match len %d, subst len %d\n",
+		(long)(p - string), olen, nlen);
+
+	/* make sure replacement matches */
+	if (*slen + nlen - olen > ssize) {
+		printf("## error: substitution buffer overflow\n");
+		return NULL;
+	}
+
+	/* move tail if needed */
+	if (olen != nlen) {
+		int tail, len;
+
+		len = (olen > nlen) ? olen : nlen;
+
+		tail = ssize - (p + len - string);
+
+		debug("## tail len %d\n", tail);
+
+		memmove(p + nlen, p + olen, tail);
+	}
+
+	/* insert substitue */
+	memcpy(p, new, nlen);
+
+	*slen += nlen - olen;
+
+	return p + nlen;
+}
+
+/*
+ * Perform regex operations on a environment variable
+ *
+ * Returns 0 if OK, 1 in case of errors.
+ */
+static int regex_sub(const char *name,
+	const char *r, const char *s, const char *t,
+	int global)
+{
+	struct slre slre;
+	char data[SLRE_BUFSZ];
+	char *datap = data;
+	const char *value;
+	int res, len, nlen, loop;
+
+	if (name == NULL)
+		return 1;
+
+	if (slre_compile(&slre, r) == 0) {
+		printf("Error compiling regex: %s\n", slre.err_str);
+		return 1;
+	}
+
+	if (t == NULL) {
+		value = getenv(name);
+
+		if (value == NULL) {
+			printf("## Error: variable \"%s\" not defined\n", name);
+			return 1;
+		}
+		t = value;
+	}
+
+	debug("REGEX on %s=%s\n", name, t);
+	debug("REGEX=\"%s\", SUBST=\"%s\", GLOBAL=%d\n",
+		r, s ? s : "<NULL>", global);
+
+	len = strlen(t);
+	if (len + 1 > SLRE_BUFSZ) {
+		printf("## error: subst buffer overflow: have %d, need %d\n",
+			SLRE_BUFSZ, len + 1);
+		return 1;
+	}
+
+	strcpy(data, t);
+
+	if (s == NULL)
+		nlen = 0;
+	else
+		nlen = strlen(s);
+
+	for (loop = 0; ;loop++) {
+		struct cap caps[slre.num_caps + 2];
+		char nbuf[SLRE_PATSZ];
+		const char *old;
+		char *np;
+		int i, olen;
+
+		(void) memset(caps, 0, sizeof(caps));
+
+		res = slre_match(&slre, datap, len, caps);
+
+		debug("Result: %d\n", res);
+
+		for (i = 0; i < slre.num_caps; i++) {
+			if (caps[i].len > 0) {
+				debug("Substring %d: [%.*s]\n", i,
+					caps[i].len, caps[i].ptr);
+			}
+		}
+
+		if (res == 0) {
+			if (loop == 0) {
+				printf("%s: No match\n", t);
+				return 1;
+			} else {
+				break;
+			}
+		}
+
+		debug("## MATCH ## %s\n", data);
+
+		if (s == NULL) {
+			printf("%s=%s\n", name, t);
+			return 1;
+		}
+
+		old = caps[0].ptr;
+		olen = caps[0].len;
+
+		if (nlen + 1 >= SLRE_PATSZ) {
+			printf("## error: pattern buffer overflow: have %d, need %d\n",
+				SLRE_BUFSZ, nlen + 1);
+			return 1;
+		}
+		strcpy(nbuf, s);
+
+		debug("## SUBST(1) ## %s\n", nbuf);
+
+		/*
+		 * Handle back references
+		 *
+		 * Support for \0 ... \9, where \0 is the
+		 * whole matched pattern (similar to &).
+		 *
+		 * Implementation is a bit simpleminded as
+		 * backrefs are substituted sequentially, one
+		 * by one.  This will lead to somewhat
+		 * unexpected results if the replacement
+		 * strings contain any \N strings then then
+		 * may get substitued, too.  We accept this
+		 * restriction for the sake of simplicity.
+		 */
+		for (i = 0; i < 10; ++i) {
+			char backref[2] = {
+				'\\',
+				'0',
+			};
+
+			if (caps[i].len == 0)
+				break;
+
+			backref[1] += i;
+
+			debug("## BACKREF %d: replace \"%.*s\" by \"%.*s\" in \"%s\"\n",
+				i,
+				2, backref,
+				caps[i].len, caps[i].ptr,
+				nbuf);
+
+			for (np = nbuf;;) {
+				char *p = memstr(np, nlen, backref, 2);
+
+				if (p == NULL)
+					break;
+
+				np = substitute(np, &nlen,
+					SLRE_PATSZ,
+					backref, 2,
+					caps[i].ptr, caps[i].len);
+
+				if (np == NULL)
+					return 1;
+			}
+		}
+		debug("## SUBST(2) ## %s\n", nbuf);
+
+		datap = substitute(datap, &len, SLRE_BUFSZ,
+				old, olen,
+				nbuf, nlen);
+
+		if (datap == NULL)
+			return 1;
+
+		debug("## REMAINDER: %s\n", datap);
+
+		debug("## RESULT: %s\n", data);
+
+		if (!global)
+			break;
+	}
+	debug("## FINAL (now setenv()) :  %s\n", data);
+
+	printf("%s=%s\n", name, data);
+
+	return setenv(name, data);
+}
+#endif
+
 static int do_setexpr(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 {
 	ulong a, b;
 	ulong value;
 	int w;
 
-	if (argc < 3)
+	/*
+	 * We take 3, 5, or 6 arguments:
+	 * 3 : setexpr name value
+	 * 5 : setexpr name val1 op val2
+	 *     setexpr name [g]sub r s
+	 * 6 : setexpr name [g]sub r s t
+	 */
+
+	/* > 6 already tested by max command args */
+	if ((argc < 3) || (argc == 4))
 		return CMD_RET_USAGE;
 
 	w = cmd_get_data_size(argv[0], 4);

@@ -69,6 +320,19 @@ static int do_setexpr(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 		return 0;
 	}
 
+	/* 5 or 6 args (6 args only with [g]sub) */
+#ifdef CONFIG_REGEX
+	/*
+	 * rexep handling: "setexpr name [g]sub r s [t]"
+	 * with 5 args, "t" will be NULL
+	 */
+	if (strcmp(argv[2], "gsub") == 0)
+		return regex_sub(argv[1], argv[3], argv[4], argv[5], 1);
+
+	if (strcmp(argv[2], "sub") == 0)
+		return regex_sub(argv[1], argv[3], argv[4], argv[5], 0);
+#endif
+
 	/* standard operators: "setexpr name val1 op val2" */
 	if (argc != 5)
 		return CMD_RET_USAGE;

@@ -114,13 +378,23 @@ static int do_setexpr(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 }
 
 U_BOOT_CMD(
-	setexpr, 5, 0, do_setexpr,
+	setexpr, 6, 0, do_setexpr,
 	"set environment variable as the result of eval expression",
 	"[.b, .w, .l] name [*]value1 <op> [*]value2\n"
 	"    - set environment variable 'name' to the result of the evaluated\n"
-	"      express specified by <op>.  <op> can be &, |, ^, +, -, *, /, %\n"
+	"      expression specified by <op>.  <op> can be &, |, ^, +, -, *, /, %\n"
 	"      size argument is only meaningful if value1 and/or value2 are\n"
 	"      memory addresses (*)\n"
 	"setexpr[.b, .w, .l] name [*]value\n"
 	"    - load a value into a variable"
+#ifdef CONFIG_REGEX
+	"\n"
+	"setexpr name gsub r s [t]\n"
+	"    - For each substring matching the regular expression <r> in the\n"
+	"      string <t>, substitute the string <s>.  The result is\n"
+	"      assigned to <name>.  If <t> is not supplied, use the old\n"
+	"      value of <name>\n"
+	"setexpr name sub r s [t]\n"
+	"    - Just like gsub(), but replace only the first matching substring"
+#endif
 );

index f2725cc..4540bf0 100644
@@ -65,6 +65,7 @@
 #define	CONFIG_CMD_EXT2
 #define	CONFIG_CMD_FAT
 #define	CONFIG_CMD_GPIO
+#define CONFIG_CMD_GREPENV
 #define	CONFIG_CMD_I2C
 #define	CONFIG_CMD_MII
 #define	CONFIG_CMD_MMC

@@ -77,6 +78,8 @@
 #define	CONFIG_CMD_SPI
 #define	CONFIG_CMD_USB
 
+#define CONFIG_REGEX			/* Enable regular expression support */
+
 /*
  * Memory configurations
  */

index f2f522d..80e5735 100644
@@ -71,6 +71,7 @@
 #define CONFIG_CMD_DIAG
 #define CONFIG_CMD_EEPROM
 #define CONFIG_CMD_ELF
+#define CONFIG_CMD_GREPENV
 #define CONFIG_CMD_I2C
 #define CONFIG_CMD_IRQ
 #define CONFIG_CMD_MII

@@ -78,6 +79,7 @@
 #define CONFIG_CMD_NFS
 #define CONFIG_CMD_PING
 #define CONFIG_CMD_REGINFO
+#define CONFIG_CMD_SETEXPR
 
 /*
  * Miscellaneous configurable options

@@ -108,13 +110,14 @@
 #define CONFIG_MX_CYCLIC		/* enable mdc/mwc commands      */
 #define CONFIG_ZERO_BOOTDELAY_CHECK	/* check for keypress on bootdelay==0 */
 #define CONFIG_VERSION_VARIABLE 	/* include version env variable */
-#define CONFIG_SYS_CONSOLE_INFO_QUIET		/* don't print console @ startup*/
+#define CONFIG_SYS_CONSOLE_INFO_QUIET	/* don't print console @ startup*/
 
-#define CONFIG_SYS_HUSH_PARSER			/* Use the HUSH parser		*/
+#define CONFIG_SYS_HUSH_PARSER		/* Use the HUSH parser		*/
 
 #define CONFIG_LOADS_ECHO		/* echo on for serial download	*/
-#define CONFIG_SYS_LOADS_BAUD_CHANGE		/* allow baudrate change	*/
+#define CONFIG_SYS_LOADS_BAUD_CHANGE	/* allow baudrate change	*/
 
+#define CONFIG_REGEX			/* Enable regular expression support */
 /*
  * BOOTP options
  */