On 21.05.2015 13:07, Pavel Boldin wrote:
> Add multikey API:
>
> * virTypedParamsFilter that returns all the parameters with specified name.
> * virTypedParamsPickStrings that returns a NULL-terminated `const char**'
> list with all the values for specified name and string type.
>
> Signed-off-by: Pavel Boldin <pboldin@xxxxxxxxxxxx>
> ---
> include/libvirt/libvirt-host.h | 10 ++++
> src/libvirt_public.syms | 6 +++
> src/util/virtypedparam.c | 107 +++++++++++++++++++++++++++++++++++++++++
> tests/virtypedparamtest.c | 96 ++++++++++++++++++++++++++++++++++++
> 4 files changed, 219 insertions(+)
>
> diff --git a/include/libvirt/libvirt-host.h b/include/libvirt/libvirt-host.h
> index 070550b..36267fc 100644
> --- a/include/libvirt/libvirt-host.h
> +++ b/include/libvirt/libvirt-host.h
> @@ -249,6 +249,11 @@ virTypedParamsGet (virTypedParameterPtr params,
> int nparams,
> const char *name);
> int
> +virTypedParamsFilter (virTypedParameterPtr params,
> + int nparams,
> + const char *name,
> + virTypedParameterPtr **ret);
> +int
> virTypedParamsGetInt (virTypedParameterPtr params,
> int nparams,
> const char *name,
> @@ -283,6 +288,11 @@ virTypedParamsGetString (virTypedParameterPtr params,
> int nparams,
> const char *name,
> const char **value);
> +const char **
> +virTypedParamsPickStrings(virTypedParameterPtr params,
> + int nparams,
> + const char *name,
> + size_t *picked);
> int
> virTypedParamsAddInt (virTypedParameterPtr *params,
> int *nparams,
> diff --git a/src/libvirt_public.syms b/src/libvirt_public.syms
> index ef3d2f0..8fc8c42 100644
> --- a/src/libvirt_public.syms
> +++ b/src/libvirt_public.syms
> @@ -710,4 +710,10 @@ LIBVIRT_1.2.15 {
> virDomainDelIOThread;
> } LIBVIRT_1.2.14;
>
> +LIBVIRT_1.2.16 {
> + global:
> + virTypedParamsFilter;
> + virTypedParamsPickStrings;
> +} LIBVIRT_1.2.15;
> +
> # .... define new API here using predicted next version number ....
> diff --git a/src/util/virtypedparam.c b/src/util/virtypedparam.c
> index ec20b74..a3d959e 100644
> --- a/src/util/virtypedparam.c
> +++ b/src/util/virtypedparam.c
> @@ -481,6 +481,58 @@ virTypedParamsGet(virTypedParameterPtr params,
> }
>
>
> +/**
> + * virTypedParamsFilter:
> + * @params: array of typed parameters
> + * @nparams: number of parameters in the @params array
> + * @name: name of the parameter to find
> + * @ret: pointer to the returned array
> + *
> + *
> + * Filters @params retaining only the parameters named @name in the
> + * resulting array @ret. Caller should free the @ret array but no the
s/no/not/
> + * items since they are pointing to the @params elements.
> + *
> + * Returns amount of elements in @ret on success, -1 on error.
> + */
> +int
> +virTypedParamsFilter(virTypedParameterPtr params,
> + int nparams,
> + const char *name,
> + virTypedParameterPtr **ret)
> +{
> + size_t i, max = 0, n = 0;
s/max/alloc/
> +
> + virResetLastError();
> +
> + if (!params || !name || !ret) {
> + virReportError(VIR_ERR_INVALID_ARG,
> + _("Required argument is missing: %s"),
> + !params ? "params" : !name ? "name" : "ret");
> + goto error;
We have a macro for that: virCheckNonNullArgGoto()
> + }
> +
> + for (i = 0; i < nparams; i++) {
> + if (STREQ(params[i].field, name)) {
> + if (VIR_RESIZE_N(*ret, max, n, 1) < 0)
> + goto error;
> +
> + (*ret)[n] = ¶ms[i];
> +
> + n++;
> + }
> + }
So if there's no match, @ret is untouched. This is not cool, consider
the following code:
virTypedParameterPtr *ret;
if (virTypedParamsFilter(.., &ret) < 0) {
error;
} else {
success;
free(ret);
}
The free() may end up freeing a random pointer.
> +
> + return n;
> +
> + error:
> + if (ret)
> + VIR_FREE(*ret);
> + virDispatchError(NULL);
> + return -1;
> +}
> +
> +
> #define VIR_TYPED_PARAM_CHECK_TYPE(check_type) \
> do { if (param->type != check_type) { \
> virReportError(VIR_ERR_INVALID_ARG, \
> @@ -749,6 +801,61 @@ virTypedParamsGetString(virTypedParameterPtr params,
>
>
> /**
> + * virTypedParamsPickStrings:
> + * @params: array of typed parameters
> + * @nparams: number of parameters in the @params array
> + * @name: name of the parameter to find
> + * @picked: pointer to the amount of picked strings.
> + *
> + *
> + * Finds typed parameters called @name.
> + *
> + * Returns a string list, which is a NULL terminated array of pointers to
> + * strings. Since a NULL is a valid parameter string value caller can ask
> + * for exact amount of picked strings using @picked argument.
This does not make much sense to me. As even your own test shows, while
you are returning a NULL terminated array, you allow NULLs to occur in
the array too. Therefore seeing a NULL item, one can't be sure if it is
an item or array margin. That's why we have @picked. But since we have
it, why we need NULL terminator?
> + *
> + * Caller should free the returned array but not the items since they are
> + * taken from @params array.
> + */
> +const char **
> +virTypedParamsPickStrings(virTypedParameterPtr params,
> + int nparams, const char *name,
> + size_t *picked)
> +{
> + const char **values = NULL;
> + size_t i, n;
> + int nfiltered;
> + virTypedParameterPtr *filtered = NULL;
> +
> + virResetLastError();
> +
> + nfiltered = virTypedParamsFilter(params, nparams, name, &filtered);
> +
> + if (nfiltered <= 0)
@picked should be updated here.
> + return NULL;
> +
> + if (VIR_ALLOC_N(values, nfiltered + 1) < 0)
> + goto error;
So, if allocation fails, NULL is returned. How is this different to case
covered in previous case (i.e. when no such param with @name was found)?
We need to distinguish these two cases.
> +
> + for (n = 0, i = 0; i < nfiltered; i++) {
> + if (filtered[i]->type == VIR_TYPED_PARAM_STRING)
> + values[n++] = filtered[i]->value.s;
> + }
> +
> + if (picked)
> + *picked = n;
> +
> + VIR_FREE(filtered);
> + return values;
> +
> + error:
> + VIR_FREE(filtered);
> + virDispatchError(NULL);
> + return NULL;
> +}
> +
> +
> +/**
> * virTypedParamsAddInt:
> * @params: pointer to the array of typed parameters
> * @nparams: number of parameters in the @params array
Michal
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