[U-Boot] [PATCH v4 7/7] env: delete selected vars not present in imported env

[Gerlando Falauto]

On 08/24/2012 04:58 PM, Marek Vasut wrote:
> Dear Gerlando Falauto,
>
>> When variables explicitly specified on the command line are not present
>> in the imported env, delete them from the running env.
>> If the variable is also missing from the running env, issue a warning.
>>
>> Signed-off-by: Gerlando Falauto<gerlando.falauto at keymile.com>
>
> Whew! I made it through ... it wasn't that scary in the end ;-)
>
>> ---
>>   lib/hashtable.c |   48 +++++++++++++++++++++++++++++++++++++++++-------
>>   1 file changed, 41 insertions(+), 7 deletions(-)
>>
>> diff --git a/lib/hashtable.c b/lib/hashtable.c
>> index f3f47de..b3d0b64 100644
>> --- a/lib/hashtable.c
>> +++ b/lib/hashtable.c
>> @@ -607,22 +607,32 @@ ssize_t hexport_r(struct hsearch_data *htab, const
>> char sep, * himport()
>>    */
>>
>> -/* Check whether variable name is amongst vars[] */
>> -static int is_var_in_set(const char *name, int nvars, char * const vars[])
>> +/*
>> + * Check whether variable 'name' is amongst vars[],
>> + * and remove all instances by setting the pointer to NULL
>> + */
>> +static int is_var_in_set(const char *name, int nvars, char * vars[])
>>   {
>>   	int i = 0;
>> +	int res = 0;
>>
>>   	/* No variables specified means process all of them */
>>   	if (nvars == 0)
>>   		return 1;
>>
>>   	for (i = 0; i<  nvars; i++) {
>> -		if (!strcmp(name, vars[i]))
>> -			return 1;
>> +		if (vars[i] == NULL)
>> +			continue;
>> +		/* If we found it, delete all of them */
>> +		if (!strcmp(name, vars[i])) {
>> +			vars[i] = NULL;
>> +			res = 1;
>
> break here ?

Nope, if we find it, we should delete all of them (see comment above).

>
>> +		}
>>   	}
>> -	debug("Skipping non-listed variable %s\n", name);
>> +	if (!res)
>> +		debug("Skipping non-listed variable %s\n", name);
>>
>> -	return 0;
>> +	return res;
>>   }
>>
>>   /*
>> @@ -662,9 +672,11 @@ static int is_var_in_set(const char *name, int nvars,
>> char * const vars[])
>>
>>   int himport_r(struct hsearch_data *htab,
>>   		const char *env, size_t size, const char sep, int flag,
>> -		int nvars, char * const vars[], int do_apply)
>> +		int nvars, char * const __vars[], int do_apply)
>
> Two underscores are reserved, use something else ;-)

Like... one? three? ;-)

>
>>   {
>>   	char *data, *sp, *dp, *name, *value;
>> +	char *vars[nvars];
>> +	int i;
>>
>>   	/* Test for correct arguments.  */
>>   	if (htab == NULL) {
>> @@ -681,6 +693,10 @@ int himport_r(struct hsearch_data *htab,
>>   	memcpy(data, env, size);
>>   	dp = data;
>>
>> +	/* make a local copy of the list of variables */
>> +	if (nvars)
>> +		memcpy(vars, __vars, sizeof(__vars[0]) * nvars);
>> +
>>   	if ((flag&  H_NOCLEAR) == 0) {
>>   		/* Destroy old hash table if one exists */
>>   		debug("Destroy Hash Table: %p table = %p\n", htab,
>> @@ -809,6 +825,24 @@ int himport_r(struct hsearch_data *htab,
>>   	debug("INSERT: free(data = %p)\n", data);
>>   	free(data);
>>
>> +	/* process variables which were not considered */
>> +	for (i = 0; i<  nvars; i++) {
>> +		if (vars[i] == NULL)
>> +			continue;
>> +		/*
>> +		 * All variables which were not deleted from the variable list
>> +		 * were not present in the imported env
>> +		 * This could mean two things:
>> +		 * a) if the variable was present in current env, we delete it
>> +		 * b) if the variable was not present in current env, we notify
>> +		 *    it might be a typo
>> +		 */
>> +		if (hdelete_r(vars[i], htab, do_apply) == 0)
>> +			printf("WARNING: '%s' neither in running nor in imported
> env!\n",
>> vars[i]); +		else
>> +			printf("WARNING: '%s' not in imported env, deleting it!
> \n", vars[i]);
>> +	}
>> +
>>   	debug("INSERT: done\n");
>>   	return 1;		/* everything OK */
>>   }
>
> Best regards,
> Marek Vasut

Best regards,
Gerlando