[PATCH 7/8] Add lvm_lv_get_property() generic function to obtain value of any lv property.
Dave Wysochanski <[email protected]>
| Newsgroups | dev.linux.lists.lvm-devel |
|---|---|
| Message-ID | <[email protected]> |
Signed-off-by: Dave Wysochanski <[email protected]> --- lib/report/properties.c | 6 ++++++ lib/report/properties.h | 2 ++ liblvm/lvm2app.h | 44 ++++++++++++++++++++++++++++++++++++++++++++ liblvm/lvm_lv.c | 20 ++++++++++++++++++++ 4 files changed, 72 insertions(+), 0 deletions(-) diff --git a/lib/report/properties.c b/lib/report/properties.c index 8f9272c..c08ddfd 100644 --- a/lib/report/properties.c +++ b/lib/report/properties.c @@ -267,6 +267,12 @@ static int _get_property(const void *obj, struct lvm_property_type *prop, return 1; } +int lv_get_property(const struct logical_volume *lv, + struct lvm_property_type *prop) +{ + return _get_property(lv, prop, LVS); +} + int vg_get_property(const struct volume_group *vg, struct lvm_property_type *prop) { diff --git a/lib/report/properties.h b/lib/report/properties.h index db4ae51..18e5ab9 100644 --- a/lib/report/properties.h +++ b/lib/report/properties.h @@ -32,6 +32,8 @@ struct lvm_property_type { int (*set) (void *obj, struct lvm_property_type *prop); }; +int lv_get_property(const struct logical_volume *lv, + struct lvm_property_type *prop); int vg_get_property(const struct volume_group *vg, struct lvm_property_type *prop); int pv_get_property(const struct physical_volume *pv, diff --git a/liblvm/lvm2app.h b/liblvm/lvm2app.h index 066f2ca..fbaf173 100644 --- a/liblvm/lvm2app.h +++ b/liblvm/lvm2app.h @@ -1034,6 +1034,50 @@ const char *lvm_lv_get_name(const lv_t lv); uint64_t lvm_lv_get_size(const lv_t lv); /** + * Get the value of a LV property + * + * \memberof lv_t + * + * \param lv + * Logical volume handle. + * + * \param name + * Name of property to query. See lvs man page for full list of properties + * that may be queried. + * + * \param value + * Pointer to an lvm_property_value structure that will contain the current + * value of the property. The pointer may be NULL if just checking the + * name of the property. + * + * The memory allocated for a string property value is tied to the vg_t + * handle and will be released when lvm_vg_close() is called. + * + * Example: + * lvm_property_value value; + * char *prop_name = "seg_count"; + * + * if (lvm_lv_get_property(lv, prop_name, NULL)) { + * printf("Invalid property name or unable to query" + * "'%s'.\n", prop_name); + * return; + * } + * if (lvm_lv_get_property(lv, prop_name, &value) < 0) { + * // handle error + * } + * if (value.is_string) + * printf(", value = %s\n", value.value.string); + * else + * printf(", value = %"PRIu64"\n", value.value.integer); + * + * + * \return + * 0 (success) or -1 (failure). + */ +int lvm_lv_get_property(const lv_t lv, const char *name, + struct lvm_property_value *value); + +/** * Get the current activation state of a logical volume. * * \memberof lv_t diff --git a/liblvm/lvm_lv.c b/liblvm/lvm_lv.c index 7bdafe0..8dd4b0a 100644 --- a/liblvm/lvm_lv.c +++ b/liblvm/lvm_lv.c @@ -21,6 +21,7 @@ #include "locking.h" #include "activate.h" #include "lvm_misc.h" +#include "properties.h" static int _lv_check_handle(const lv_t lv, const int vg_writeable) { @@ -48,6 +49,25 @@ const char *lvm_lv_get_name(const lv_t lv) NAME_LEN+1); } +int lvm_lv_get_property(const lv_t lv, const char *name, + struct lvm_property_value *value) +{ + struct lvm_property_type prop; + + prop.id = name; + if (!lv_get_property(lv, &prop)) + return -1; + if (!value) + return 0; + value->is_settable = prop.is_settable; + value->is_string = prop.is_string; + if (value->is_string) + value->value.string = prop.value.string; + else + value->value.integer = prop.value.integer; + return 0; +} + uint64_t lvm_lv_is_active(const lv_t lv) { struct lvinfo info; -- 1.7.2.2