Re: [Qemu-devel] [PATCH v2 4/7] device_tree: qemu_fdt_getprop converted to use the error API
Hi Peter,
On 01/07/2016 01:20 AM, Peter Crosthwaite wrote:
> On Wed, Jan 6, 2016 at 7:13 AM, Eric Auger wrote:
>> Current qemu_fdt_getprop exits if the property is not found. It is
>> sometimes needed to read an optional property, in which case we do
>> not wish to exit but simply returns a null value.
>>
>> This patch converts qemu_fdt_getprop to accept an Error **, and existing
>> users are converted to pass &error_fatal. This preserves the existing
>> behaviour. Then to use the API with your optional semantic a null
>> parameter can be conveyed.
>>
>> Signed-off-by: Eric Auger
>>
>> ---
>>
>> v1 -> v2:
>> - add a doc comment in the header file
>>
>> RFC -> v1:
>> - get rid of qemu_fdt_getprop_optional and implement Peter's suggestion
>> that consists in using the error API
>>
>> Signed-off-by: Eric Auger
>> ---
>> device_tree.c| 11 ++-
>> include/sysemu/device_tree.h | 15 ++-
>> 2 files changed, 20 insertions(+), 6 deletions(-)
>>
>> diff --git a/device_tree.c b/device_tree.c
>> index 8441e01..6ecc9da 100644
>> --- a/device_tree.c
>> +++ b/device_tree.c
>> @@ -321,18 +321,18 @@ int qemu_fdt_setprop_string(void *fdt, const char
>> *node_path,
>> }
>>
>> const void *qemu_fdt_getprop(void *fdt, const char *node_path,
>> - const char *property, int *lenp)
>> + const char *property, int *lenp, Error **errp)
>> {
>> int len;
>> const void *r;
>> +
>> if (!lenp) {
>> lenp = &len;
>> }
>> r = fdt_getprop(fdt, findnode_nofail(fdt, node_path), property, lenp);
>> if (!r) {
>> -error_report("%s: Couldn't get %s/%s: %s", __func__,
>> - node_path, property, fdt_strerror(*lenp));
>> -exit(1);
>> +error_setg(errp, "%s: Couldn't get %s/%s: %s", __func__,
>> + node_path, property, fdt_strerror(*lenp));
>> }
>> return r;
>> }
>> @@ -341,7 +341,8 @@ uint32_t qemu_fdt_getprop_cell(void *fdt, const char
>> *node_path,
>> const char *property)
>> {
>> int len;
>> -const uint32_t *p = qemu_fdt_getprop(fdt, node_path, property, &len);
>> +const uint32_t *p = qemu_fdt_getprop(fdt, node_path, property, &len,
>> + &error_fatal);
>
> The _cell variant is now inconsistent with the regular _getprop. Can
> we convert them both together and fix the clients to error_fatal?
> (there are only 4 of them).
Yes sure
Best Regards
Eric
>
> This would become the standard error_propagate pattern.
>
>> if (len != 4) {
>> error_report("%s: %s/%s not 4 bytes long (not a cell?)",
>> __func__, node_path, property);
>
> And this would also convert to error_setg.
>
> Regards,
> Peter
>
>> diff --git a/include/sysemu/device_tree.h b/include/sysemu/device_tree.h
>> index 269cb1c..4d7cbb9 100644
>> --- a/include/sysemu/device_tree.h
>> +++ b/include/sysemu/device_tree.h
>> @@ -45,8 +45,21 @@ int qemu_fdt_setprop_string(void *fdt, const char
>> *node_path,
>> int qemu_fdt_setprop_phandle(void *fdt, const char *node_path,
>> const char *property,
>> const char *target_node_path);
>> +/**
>> + * qemu_fdt_getprop: retrieve the value of a given property
>> + * @fdt: pointer to the device tree blob
>> + * @node_path: node path
>> + * @property: name of the property to find
>> + * @lenp: fdt error if any or length of the property on success
>> + * @errp: handle to an error object
>> + *
>> + * returns a pointer to the property on success and NULL on failure
>> + * in case errp is set to &error_fatal, the function auto-asserts
>> + * on error (legacy behavior)
>> + */
>> const void *qemu_fdt_getprop(void *fdt, const char *node_path,
>> - const char *property, int *lenp);
>> + const char *property, int *lenp,
>> + Error **errp);
>> uint32_t qemu_fdt_getprop_cell(void *fdt, const char *node_path,
>> const char *property);
>> uint32_t qemu_fdt_get_phandle(void *fdt, const char *path);
>> --
>> 1.9.1
>>
Re: [Qemu-devel] [PATCH v2 4/7] device_tree: qemu_fdt_getprop converted to use the error API
On Wed, Jan 6, 2016 at 7:13 AM, Eric Auger wrote:
> Current qemu_fdt_getprop exits if the property is not found. It is
> sometimes needed to read an optional property, in which case we do
> not wish to exit but simply returns a null value.
>
> This patch converts qemu_fdt_getprop to accept an Error **, and existing
> users are converted to pass &error_fatal. This preserves the existing
> behaviour. Then to use the API with your optional semantic a null
> parameter can be conveyed.
>
> Signed-off-by: Eric Auger
>
> ---
>
> v1 -> v2:
> - add a doc comment in the header file
>
> RFC -> v1:
> - get rid of qemu_fdt_getprop_optional and implement Peter's suggestion
> that consists in using the error API
>
> Signed-off-by: Eric Auger
> ---
> device_tree.c| 11 ++-
> include/sysemu/device_tree.h | 15 ++-
> 2 files changed, 20 insertions(+), 6 deletions(-)
>
> diff --git a/device_tree.c b/device_tree.c
> index 8441e01..6ecc9da 100644
> --- a/device_tree.c
> +++ b/device_tree.c
> @@ -321,18 +321,18 @@ int qemu_fdt_setprop_string(void *fdt, const char
> *node_path,
> }
>
> const void *qemu_fdt_getprop(void *fdt, const char *node_path,
> - const char *property, int *lenp)
> + const char *property, int *lenp, Error **errp)
> {
> int len;
> const void *r;
> +
> if (!lenp) {
> lenp = &len;
> }
> r = fdt_getprop(fdt, findnode_nofail(fdt, node_path), property, lenp);
> if (!r) {
> -error_report("%s: Couldn't get %s/%s: %s", __func__,
> - node_path, property, fdt_strerror(*lenp));
> -exit(1);
> +error_setg(errp, "%s: Couldn't get %s/%s: %s", __func__,
> + node_path, property, fdt_strerror(*lenp));
> }
> return r;
> }
> @@ -341,7 +341,8 @@ uint32_t qemu_fdt_getprop_cell(void *fdt, const char
> *node_path,
> const char *property)
> {
> int len;
> -const uint32_t *p = qemu_fdt_getprop(fdt, node_path, property, &len);
> +const uint32_t *p = qemu_fdt_getprop(fdt, node_path, property, &len,
> + &error_fatal);
The _cell variant is now inconsistent with the regular _getprop. Can
we convert them both together and fix the clients to error_fatal?
(there are only 4 of them).
This would become the standard error_propagate pattern.
> if (len != 4) {
> error_report("%s: %s/%s not 4 bytes long (not a cell?)",
> __func__, node_path, property);
And this would also convert to error_setg.
Regards,
Peter
> diff --git a/include/sysemu/device_tree.h b/include/sysemu/device_tree.h
> index 269cb1c..4d7cbb9 100644
> --- a/include/sysemu/device_tree.h
> +++ b/include/sysemu/device_tree.h
> @@ -45,8 +45,21 @@ int qemu_fdt_setprop_string(void *fdt, const char
> *node_path,
> int qemu_fdt_setprop_phandle(void *fdt, const char *node_path,
> const char *property,
> const char *target_node_path);
> +/**
> + * qemu_fdt_getprop: retrieve the value of a given property
> + * @fdt: pointer to the device tree blob
> + * @node_path: node path
> + * @property: name of the property to find
> + * @lenp: fdt error if any or length of the property on success
> + * @errp: handle to an error object
> + *
> + * returns a pointer to the property on success and NULL on failure
> + * in case errp is set to &error_fatal, the function auto-asserts
> + * on error (legacy behavior)
> + */
> const void *qemu_fdt_getprop(void *fdt, const char *node_path,
> - const char *property, int *lenp);
> + const char *property, int *lenp,
> + Error **errp);
> uint32_t qemu_fdt_getprop_cell(void *fdt, const char *node_path,
> const char *property);
> uint32_t qemu_fdt_get_phandle(void *fdt, const char *path);
> --
> 1.9.1
>
[Qemu-devel] [PATCH v2 4/7] device_tree: qemu_fdt_getprop converted to use the error API
Current qemu_fdt_getprop exits if the property is not found. It is
sometimes needed to read an optional property, in which case we do
not wish to exit but simply returns a null value.
This patch converts qemu_fdt_getprop to accept an Error **, and existing
users are converted to pass &error_fatal. This preserves the existing
behaviour. Then to use the API with your optional semantic a null
parameter can be conveyed.
Signed-off-by: Eric Auger
---
v1 -> v2:
- add a doc comment in the header file
RFC -> v1:
- get rid of qemu_fdt_getprop_optional and implement Peter's suggestion
that consists in using the error API
Signed-off-by: Eric Auger
---
device_tree.c| 11 ++-
include/sysemu/device_tree.h | 15 ++-
2 files changed, 20 insertions(+), 6 deletions(-)
diff --git a/device_tree.c b/device_tree.c
index 8441e01..6ecc9da 100644
--- a/device_tree.c
+++ b/device_tree.c
@@ -321,18 +321,18 @@ int qemu_fdt_setprop_string(void *fdt, const char
*node_path,
}
const void *qemu_fdt_getprop(void *fdt, const char *node_path,
- const char *property, int *lenp)
+ const char *property, int *lenp, Error **errp)
{
int len;
const void *r;
+
if (!lenp) {
lenp = &len;
}
r = fdt_getprop(fdt, findnode_nofail(fdt, node_path), property, lenp);
if (!r) {
-error_report("%s: Couldn't get %s/%s: %s", __func__,
- node_path, property, fdt_strerror(*lenp));
-exit(1);
+error_setg(errp, "%s: Couldn't get %s/%s: %s", __func__,
+ node_path, property, fdt_strerror(*lenp));
}
return r;
}
@@ -341,7 +341,8 @@ uint32_t qemu_fdt_getprop_cell(void *fdt, const char
*node_path,
const char *property)
{
int len;
-const uint32_t *p = qemu_fdt_getprop(fdt, node_path, property, &len);
+const uint32_t *p = qemu_fdt_getprop(fdt, node_path, property, &len,
+ &error_fatal);
if (len != 4) {
error_report("%s: %s/%s not 4 bytes long (not a cell?)",
__func__, node_path, property);
diff --git a/include/sysemu/device_tree.h b/include/sysemu/device_tree.h
index 269cb1c..4d7cbb9 100644
--- a/include/sysemu/device_tree.h
+++ b/include/sysemu/device_tree.h
@@ -45,8 +45,21 @@ int qemu_fdt_setprop_string(void *fdt, const char *node_path,
int qemu_fdt_setprop_phandle(void *fdt, const char *node_path,
const char *property,
const char *target_node_path);
+/**
+ * qemu_fdt_getprop: retrieve the value of a given property
+ * @fdt: pointer to the device tree blob
+ * @node_path: node path
+ * @property: name of the property to find
+ * @lenp: fdt error if any or length of the property on success
+ * @errp: handle to an error object
+ *
+ * returns a pointer to the property on success and NULL on failure
+ * in case errp is set to &error_fatal, the function auto-asserts
+ * on error (legacy behavior)
+ */
const void *qemu_fdt_getprop(void *fdt, const char *node_path,
- const char *property, int *lenp);
+ const char *property, int *lenp,
+ Error **errp);
uint32_t qemu_fdt_getprop_cell(void *fdt, const char *node_path,
const char *property);
uint32_t qemu_fdt_get_phandle(void *fdt, const char *path);
--
1.9.1
