From 18a101f31bb2fd5e831be010e6435a7c8ddc5e2f Mon Sep 17 00:00:00 2001 From: Olivier Matz Date: Fri, 24 Sep 2021 14:09:37 +0200 Subject: [PATCH] kvargs: new function to get from key and value A quite common scenario with kvargs is to lookup for a = in a kvlist. For instance, check if name=foo is present in name=toto,name=foo,name=bar. This is currently done in drivers/bus with rte_kvargs_process() + the rte_kvargs_strcmp() handler. This approach is not straightforward, and can be replaced by this new function. Signed-off-by: Olivier Matz --- drivers/bus/auxiliary/auxiliary_params.c | 9 ++++---- drivers/bus/vdev/vdev_params.c | 13 ++--------- lib/kvargs/rte_kvargs.c | 23 +++++++++++++++---- lib/kvargs/rte_kvargs.h | 29 +++++++++++++++++++++++- lib/kvargs/version.map | 2 ++ 5 files changed, 54 insertions(+), 22 deletions(-) diff --git a/drivers/bus/auxiliary/auxiliary_params.c b/drivers/bus/auxiliary/auxiliary_params.c index cd3fa56cb4..a9c7853ed1 100644 --- a/drivers/bus/auxiliary/auxiliary_params.c +++ b/drivers/bus/auxiliary/auxiliary_params.c @@ -25,13 +25,12 @@ auxiliary_dev_match(const struct rte_device *dev, const void *_kvlist) { const struct rte_kvargs *kvlist = _kvlist; - int ret; + const char *key = auxiliary_params_keys[RTE_AUXILIARY_PARAM_NAME]; - ret = rte_kvargs_process(kvlist, - auxiliary_params_keys[RTE_AUXILIARY_PARAM_NAME], - rte_kvargs_strcmp, (void *)(uintptr_t)dev->name); + if (rte_kvargs_get_with_value(kvlist, key, dev->name) == NULL) + return -1; - return ret != 0 ? -1 : 0; + return 0; } void * diff --git a/drivers/bus/vdev/vdev_params.c b/drivers/bus/vdev/vdev_params.c index 6f74704d1c..37d95395e7 100644 --- a/drivers/bus/vdev/vdev_params.c +++ b/drivers/bus/vdev/vdev_params.c @@ -26,19 +26,10 @@ static int vdev_dev_match(const struct rte_device *dev, const void *_kvlist) { - int ret; const struct rte_kvargs *kvlist = _kvlist; - char *name; + const char *key = vdev_params_keys[RTE_VDEV_PARAM_NAME]; - /* cannot pass const dev->name to rte_kvargs_process() */ - name = strdup(dev->name); - if (name == NULL) - return -1; - ret = rte_kvargs_process(kvlist, - vdev_params_keys[RTE_VDEV_PARAM_NAME], - rte_kvargs_strcmp, name); - free(name); - if (ret != 0) + if (rte_kvargs_get_with_value(kvlist, key, dev->name) == NULL) return -1; return 0; diff --git a/lib/kvargs/rte_kvargs.c b/lib/kvargs/rte_kvargs.c index 38e9d5c1ca..20abb23183 100644 --- a/lib/kvargs/rte_kvargs.c +++ b/lib/kvargs/rte_kvargs.c @@ -204,21 +204,34 @@ rte_kvargs_free(struct rte_kvargs *kvlist) free(kvlist); } -/* Lookup a value in an rte_kvargs list by its key. */ +/* Lookup a value in an rte_kvargs list by its key and value. */ const char * -rte_kvargs_get(const struct rte_kvargs *kvlist, const char *key) +rte_kvargs_get_with_value(const struct rte_kvargs *kvlist, const char *key, + const char *value) { unsigned int i; - if (kvlist == NULL || key == NULL) + if (kvlist == NULL) return NULL; for (i = 0; i < kvlist->count; ++i) { - if (strcmp(kvlist->pairs[i].key, key) == 0) - return kvlist->pairs[i].value; + if (key != NULL && strcmp(kvlist->pairs[i].key, key) != 0) + continue; + if (value != NULL && strcmp(kvlist->pairs[i].value, value) != 0) + continue; + return kvlist->pairs[i].value; } return NULL; } +/* Lookup a value in an rte_kvargs list by its key. */ +const char * +rte_kvargs_get(const struct rte_kvargs *kvlist, const char *key) +{ + if (kvlist == NULL || key == NULL) + return NULL; + return rte_kvargs_get_with_value(kvlist, key, NULL); +} + /* * Parse the arguments "key=value,key=value,..." string and return * an allocated structure that contains a key/value list. Also diff --git a/lib/kvargs/rte_kvargs.h b/lib/kvargs/rte_kvargs.h index ba34b1ae70..135c4b3e40 100644 --- a/lib/kvargs/rte_kvargs.h +++ b/lib/kvargs/rte_kvargs.h @@ -116,7 +116,7 @@ void rte_kvargs_free(struct rte_kvargs *kvlist); /** * Get the value associated with a given key. * - * If multiple key matches, the value of the first one is returned. + * If multiple keys match, the value of the first one is returned. * * The memory returned is allocated as part of the rte_kvargs structure, * it must never be modified. @@ -132,6 +132,33 @@ void rte_kvargs_free(struct rte_kvargs *kvlist); */ const char *rte_kvargs_get(const struct rte_kvargs *kvlist, const char *key); +/** + * @warning + * @b EXPERIMENTAL: this API may change without prior notice + * + * Get the value associated with a given key and value. + * + * Find the first entry in the kvlist whose key and value match the + * ones passed as argument. + * + * The memory returned is allocated as part of the rte_kvargs structure, + * it must never be modified. + * + * @param kvlist + * A list of rte_kvargs pair of 'key=value'. + * @param key + * The matching key. If NULL, any key will match. + * @param value + * The matching value. If NULL, any value will match. + * + * @return + * NULL if no key matches the input, + * a value associated with a matching key otherwise. + */ +__rte_experimental +const char *rte_kvargs_get_with_value(const struct rte_kvargs *kvlist, + const char *key, const char *value); + /** * Call a handler function for each key/value matching the key * diff --git a/lib/kvargs/version.map b/lib/kvargs/version.map index 236f35c02b..82879b7140 100644 --- a/lib/kvargs/version.map +++ b/lib/kvargs/version.map @@ -16,4 +16,6 @@ EXPERIMENTAL { rte_kvargs_strcmp; + # added in 21.11 + rte_kvargs_get_with_value; }; -- 2.20.1