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authorYang Zhang <yang.z.zhang@intel.com>2015-08-28 09:58:54 +0800
committerYang Zhang <yang.z.zhang@intel.com>2015-09-01 12:44:00 +0800
commite44e3482bdb4d0ebde2d8b41830ac2cdb07948fb (patch)
tree66b09f592c55df2878107a468a91d21506104d3f /qemu/roms/u-boot/common/env_callback.c
parent9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (diff)
Add qemu 2.4.0
Change-Id: Ic99cbad4b61f8b127b7dc74d04576c0bcbaaf4f5 Signed-off-by: Yang Zhang <yang.z.zhang@intel.com>
Diffstat (limited to 'qemu/roms/u-boot/common/env_callback.c')
-rw-r--r--qemu/roms/u-boot/common/env_callback.c135
1 files changed, 135 insertions, 0 deletions
diff --git a/qemu/roms/u-boot/common/env_callback.c b/qemu/roms/u-boot/common/env_callback.c
new file mode 100644
index 000000000..d03fa03a4
--- /dev/null
+++ b/qemu/roms/u-boot/common/env_callback.c
@@ -0,0 +1,135 @@
+/*
+ * (C) Copyright 2012
+ * Joe Hershberger, National Instruments, joe.hershberger@ni.com
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#include <common.h>
+#include <environment.h>
+
+#if defined(CONFIG_NEEDS_MANUAL_RELOC)
+DECLARE_GLOBAL_DATA_PTR;
+#endif
+
+/*
+ * Look up a callback function pointer by name
+ */
+static struct env_clbk_tbl *find_env_callback(const char *name)
+{
+ struct env_clbk_tbl *clbkp;
+ int i;
+ int num_callbacks = ll_entry_count(struct env_clbk_tbl, env_clbk);
+
+ if (name == NULL)
+ return NULL;
+
+ /* look up the callback in the linker-list */
+ for (i = 0, clbkp = ll_entry_start(struct env_clbk_tbl, env_clbk);
+ i < num_callbacks;
+ i++, clbkp++) {
+ if (strcmp(name, clbkp->name) == 0)
+ return clbkp;
+ }
+
+ return NULL;
+}
+
+static int first_call = 1;
+static const char *callback_list;
+
+/*
+ * Look for a possible callback for a newly added variable
+ * This is called specifically when the variable did not exist in the hash
+ * previously, so the blanket update did not find this variable.
+ */
+void env_callback_init(ENTRY *var_entry)
+{
+ const char *var_name = var_entry->key;
+ char callback_name[256] = "";
+ struct env_clbk_tbl *clbkp;
+ int ret = 1;
+
+ if (first_call) {
+ callback_list = getenv(ENV_CALLBACK_VAR);
+ first_call = 0;
+ }
+
+ /* look in the ".callbacks" var for a reference to this variable */
+ if (callback_list != NULL)
+ ret = env_attr_lookup(callback_list, var_name, callback_name);
+
+ /* only if not found there, look in the static list */
+ if (ret)
+ ret = env_attr_lookup(ENV_CALLBACK_LIST_STATIC, var_name,
+ callback_name);
+
+ /* if an association was found, set the callback pointer */
+ if (!ret && strlen(callback_name)) {
+ clbkp = find_env_callback(callback_name);
+ if (clbkp != NULL)
+#if defined(CONFIG_NEEDS_MANUAL_RELOC)
+ var_entry->callback = clbkp->callback + gd->reloc_off;
+#else
+ var_entry->callback = clbkp->callback;
+#endif
+ }
+}
+
+/*
+ * Called on each existing env var prior to the blanket update since removing
+ * a callback association should remove its callback.
+ */
+static int clear_callback(ENTRY *entry)
+{
+ entry->callback = NULL;
+
+ return 0;
+}
+
+/*
+ * Call for each element in the list that associates variables to callbacks
+ */
+static int set_callback(const char *name, const char *value)
+{
+ ENTRY e, *ep;
+ struct env_clbk_tbl *clbkp;
+
+ e.key = name;
+ e.data = NULL;
+ hsearch_r(e, FIND, &ep, &env_htab, 0);
+
+ /* does the env variable actually exist? */
+ if (ep != NULL) {
+ /* the assocaition delares no callback, so remove the pointer */
+ if (value == NULL || strlen(value) == 0)
+ ep->callback = NULL;
+ else {
+ /* assign the requested callback */
+ clbkp = find_env_callback(value);
+ if (clbkp != NULL)
+#if defined(CONFIG_NEEDS_MANUAL_RELOC)
+ ep->callback = clbkp->callback + gd->reloc_off;
+#else
+ ep->callback = clbkp->callback;
+#endif
+ }
+ }
+
+ return 0;
+}
+
+static int on_callbacks(const char *name, const char *value, enum env_op op,
+ int flags)
+{
+ /* remove all callbacks */
+ hwalk_r(&env_htab, clear_callback);
+
+ /* configure any static callback bindings */
+ env_attr_walk(ENV_CALLBACK_LIST_STATIC, set_callback);
+ /* configure any dynamic callback bindings */
+ env_attr_walk(value, set_callback);
+
+ return 0;
+}
+U_BOOT_ENV_CALLBACK(callbacks, on_callbacks);