u-boot/env/callback.c
Tom Rini 83d290c56f SPDX: Convert all of our single license tags to Linux Kernel style
When U-Boot started using SPDX tags we were among the early adopters and
there weren't a lot of other examples to borrow from.  So we picked the
area of the file that usually had a full license text and replaced it
with an appropriate SPDX-License-Identifier: entry.  Since then, the
Linux Kernel has adopted SPDX tags and they place it as the very first
line in a file (except where shebangs are used, then it's second line)
and with slightly different comment styles than us.

In part due to community overlap, in part due to better tag visibility
and in part for other minor reasons, switch over to that style.

This commit changes all instances where we have a single declared
license in the tag as both the before and after are identical in tag
contents.  There's also a few places where I found we did not have a tag
and have introduced one.

Signed-off-by: Tom Rini <trini@konsulko.com>
2018-05-07 09:34:12 -04:00

135 lines
3.2 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* (C) Copyright 2012
* Joe Hershberger, National Instruments, joe.hershberger@ni.com
*/
#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 = env_get(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, void *priv)
{
ENTRY e, *ep;
struct env_clbk_tbl *clbkp;
e.key = name;
e.data = NULL;
e.callback = 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, NULL);
/* configure any dynamic callback bindings */
env_attr_walk(value, set_callback, NULL);
return 0;
}
U_BOOT_ENV_CALLBACK(callbacks, on_callbacks);