[U-Boot] [PATCH v2 07/19] env: Add regex support to env_attrs

Joe Hershberger
2015-04-29T05:50:54Z

Allow the features that use env_attrs to specify regexs for the name

Signed-off-by: Joe Hershberger <joe.hershberger@ni.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
---

Changes in v2:
-Added description to README

README | 8 +++++
common/env_attr.c | 85 ++++++++++++++++++++++++++++++++++++++++++++++++++
include/env_callback.h | 10 ++++--
3 files changed, 101 insertions(+), 2 deletions(-)

diff --git a/README b/README
index ee65fdb..5956329 100644
--- a/README
+++ b/README
@@ -4157,6 +4157,10 @@ Configuration Settings:
list, simply add an entry for the same variable name to the
".flags" variable.

+ If CONFIG_REGEX is defined, the variable_name above is evaluated as a
+ regular expression. This allows multiple variables to define the same
+ flags without explicitly listing them for each variable.
+
- CONFIG_ENV_ACCESS_IGNORE_FORCE
If defined, don't allow the -f switch to env set override variable
access flags.
@@ -5555,6 +5559,10 @@ override any association in the static list. You can define
CONFIG_ENV_CALLBACK_LIST_DEFAULT to a list (string) to define the
".callbacks" environment variable in the default or embedded environment.

+If CONFIG_REGEX is defined, the variable_name above is evaluated as a
+regular expression. This allows multiple variables to be connected to
+the same callback without explicitly listing them all out.
+

Command Line Parsing:
=====================
diff --git a/common/env_attr.c b/common/env_attr.c
index b9de16f..5bfe5e3 100644
--- a/common/env_attr.c
+++ b/common/env_attr.c
@@ -11,6 +11,7 @@
#include <linux/linux_string.h>
#else
#include <common.h>
+#include <slre.h>
#endif

#include <env_attr.h>
@@ -109,6 +110,89 @@ int env_attr_walk(const char *attr_list,
return 0;
}

+#if defined(CONFIG_REGEX)
+struct regex_callback_priv {
+ const char *searched_for;
+ char *regex;
+ char *attributes;
+};
+
+static int regex_callback(const char *name, const char *attributes, void *priv)
+{
+ int retval = 0;
+ struct regex_callback_priv *cbp = (struct regex_callback_priv *)priv;
+ struct slre slre;
+ char regex[strlen(name) + 3];
+
+ /* Require the whole string to be described by the regex */
+ sprintf(regex, "^%s$", name);
+ if (slre_compile(&slre, regex)) {
+ struct cap caps[slre.num_caps + 2];
+
+ if (slre_match(&slre, cbp->searched_for,
+ strlen(cbp->searched_for), caps)) {
+ free(cbp->regex);
+ cbp->regex = malloc(strlen(regex) + 1);
+ if (cbp->regex) {
+ strcpy(cbp->regex, regex);
+ } else {
+ retval = -ENOMEM;
+ goto done;
+ }
+
+ free(cbp->attributes);
+ cbp->attributes = malloc(strlen(attributes) + 1);
+ if (cbp->attributes) {
+ strcpy(cbp->attributes, attributes);
+ } else {
+ retval = -ENOMEM;
+ free(cbp->regex);
+ cbp->regex = NULL;
+ goto done;
+ }
+ }
+ } else {
+ printf("Error compiling regex: %s\n", slre.err_str);
+ retval = EINVAL;
+ }
+done:
+ return retval;
+}
+
+/*
+ * Retrieve the attributes string associated with a single name in the list
+ * There is no protection on attributes being too small for the value
+ */
+int env_attr_lookup(const char *attr_list, const char *name, char *attributes)
+{
+ if (!attributes)
+ /* bad parameter */
+ return -EINVAL;
+ if (!attr_list)
+ /* list not found */
+ return -EINVAL;
+
+ struct regex_callback_priv priv;
+ int retval;
+
+ priv.searched_for = name;
+ priv.regex = NULL;
+ priv.attributes = NULL;
+ retval = env_attr_walk(attr_list, regex_callback, &priv);
+ if (retval)
+ return retval; /* error */
+
+ if (priv.regex) {
+ strcpy(attributes, priv.attributes);
+ free(priv.attributes);
+ free(priv.regex);
+ /* success */
+ return 0;
+ }
+ return -ENOENT; /* not found in list */
+}
+#else
+
/*
* Search for the last exactly matching name in an attribute list
*/
@@ -219,3 +303,4 @@ int env_attr_lookup(const char *attr_list, const char *name, char *attributes)
/* not found in list */
return -ENOENT;
}
+#endif
diff --git a/include/env_callback.h b/include/env_callback.h
index ab4e115..3de1093 100644
--- a/include/env_callback.h
+++ b/include/env_callback.h
@@ -31,12 +31,18 @@
#define SPLASHIMAGE_CALLBACK
#endif

+#ifdef CONFIG_REGEX
+#define ENV_DOT_ESCAPE "\\"
+#else
+#define ENV_DOT_ESCAPE
+#endif
+
/*
* This list of callback bindings is static, but may be overridden by defining
* a new association in the ".callbacks" environment variable.
*/
-#define ENV_CALLBACK_LIST_STATIC ENV_CALLBACK_VAR ":callbacks," \
- ENV_FLAGS_VAR ":flags," \
+#define ENV_CALLBACK_LIST_STATIC ENV_DOT_ESCAPE ENV_CALLBACK_VAR ":callbacks," \
+ ENV_DOT_ESCAPE ENV_FLAGS_VAR ":flags," \
"baudrate:baudrate," \
"bootfile:bootfile," \
"loadaddr:loadaddr," \
--
1.7.11.5