Re: [PATCH 2/3] blspec: add new blspec.compatible.extra variable

[Ahmad Fatoum <a.fatoum@pengutronix.de>]

On 20.09.23 14:37, Rouven Czerwinski wrote:
> The blspec.compatible.extra variable will be used to specify extra

As this is only relevant when booting. Maybe prefix with boot.?
Not sure if that wouldn't be too long..

> compatibles that are also used to match during bootloader specification
> entry parsing. This means that even if your internal barebox device tree
> machine compatible is "vendor,bareboxcompatible", but your bootloader
> specification device tree contains "vendor,linuxcompatible", it is
> possible to boot this entry by setting blspec.compatible.extra to
> "vendor,linuxcompatible".
> 
> More than one compatible is possible as well, the compatibles will need
> to be space separated (since "," is already used for the vendor hardware
> distinction).
> 
> Signed-off-by: Rouven Czerwinski <r.czerwinski@pengutronix.de>
> ---
>  common/blspec.c | 56 +++++++++++++++++++++++++++++++++++++++++++++++++
>  1 file changed, 56 insertions(+)
> 
> diff --git a/common/blspec.c b/common/blspec.c
> index f8d47f20d2..e361a02333 100644
> --- a/common/blspec.c
> +++ b/common/blspec.c
> @@ -19,10 +19,20 @@
>  #include <net.h>
>  #include <fs.h>
>  #include <of.h>
> +#include <magicvar.h>
> +#include <linux/list.h>
>  #include <linux/stat.h>
>  #include <linux/err.h>
>  #include <mtd/ubi-user.h>
>  
> +struct list_head *blspec_extra_list;
> +char *blspec_extra_string;
> +
> +struct blspec_extra_entry {
> +	char *compatible;
> +	struct list_head list;
> +};
> +
>  /*
>   * blspec_entry_var_set - set a variable to a value
>   */
> @@ -830,8 +840,54 @@ static int blspec_bootentry_provider(struct bootentries *bootentries,
>  	return found;
>  }
>  
> +static int blspec_extra_set(struct param_d *p, void *priv)
> +{
> +	struct blspec_extra_entry *entry, *tmp;
> +	char *str = blspec_extra_string;
> +	char *temp = str;
> +	unsigned int len;
> +
> +	if (blspec_extra_list) {
> +		list_for_each_entry_safe(entry, tmp, blspec_extra_list, list) {
> +			list_del(&entry->list);
> +			free(entry->compatible);
> +			free(entry);
> +		}
> +		blspec_extra_list = NULL;
> +	}
> +
> +	while(str++) {
> +		if (*str == ' ' || *str == 0) {

Please use strsep (or strsep_unescaped) as elsewhere in blspec.c. 

> +			len = temp - str;
> +			if(len > 126) {
> +				len = 127;
> +			}
> +			entry = calloc(1, sizeof(struct blspec_extra_entry));

xzalloc if you don't check for !NULL.

> +			entry->compatible = xzalloc(len + 1);
> +			memcpy(entry->compatible, temp, len);

But here you could just use xstrdup?

> +
> +			if (blspec_extra_list == NULL) {
> +				INIT_LIST_HEAD(&entry->list);
> +				blspec_extra_list = &entry->list;

This is unusal. Why not have blspec_extra_list be a list_head instead of a pointer?

> +			} else {
> +				list_add_tail(&entry->list, blspec_extra_list);
> +			}
> +
> +			temp = str + 1;
> +		}
> +		if (*str == 0)
> +			break;
> +	}
> +
> +	return 0;
> +}
> +
>  static int blspec_init(void)
>  {
> +	dev_add_param_string(&global_device, "blspec.compatible.extra",
> +			     blspec_extra_set, NULL, &blspec_extra_string, blspec_extra_list);
>  	return bootentry_register_provider(blspec_bootentry_provider);
>  }
>  device_initcall(blspec_init);
> +
> +BAREBOX_MAGICVAR(global.blspec.compatible.extra, "Extra compatible to also match during bootloader entry matching");

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