| Message ID | 1452093205-30167-5-git-send-email-eric.auger@linaro.org |
|---|---|
| State | New |
| Headers | show |
On Wed, Jan 6, 2016 at 7:13 AM, Eric Auger <eric.auger@linaro.org> 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 <eric.auger@linaro.org> > > --- > > 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 <eric.auger@linaro.org> > --- > 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 >
Hi Peter, On 01/07/2016 01:20 AM, Peter Crosthwaite wrote: > On Wed, Jan 6, 2016 at 7:13 AM, Eric Auger <eric.auger@linaro.org> 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 <eric.auger@linaro.org> >> >> --- >> >> 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 <eric.auger@linaro.org> >> --- >> 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 >>
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);