Introduce a cgroup_tree_handle structure so that we can track flags for the walk_tree operation. In a number of cases we would prefer to walk the tree in postorder as opposed to pre-order which is the current default. This patch does the addition.
Changes since V1: 1. Added checks for !handle as suggested by Bharata Signed-off-by: Dhaval Giani <[email protected]> --- include/libcgroup.h | 10 +++++++ src/api.c | 60 +++++++++++++++++++++++++++++++++++++++-------- src/libcgroup-internal.h | 9 +++++++ 3 files changed, 69 insertions(+), 10 deletions(-) Index: libcg/src/libcgroup-internal.h =================================================================== --- libcg.orig/src/libcgroup-internal.h +++ libcg/src/libcgroup-internal.h @@ -19,8 +19,11 @@ __BEGIN_DECLS #include "config.h" +#include <fts.h> #include <libcgroup.h> #include <limits.h> +#include <sys/stat.h> +#include <sys/types.h> #define CGRULES_CONF_FILE "/etc/cgrules.conf" #define CGRULES_MAX_FIELDS_PER_LINE 3 @@ -87,6 +90,12 @@ struct cgroup_rule_list { int len; }; +/*The walk_tree handle */ +struct cgroup_tree_handle { + FTS *fts; + int flags; +}; + /* Internal API */ char *cg_build_path(char *name, char *path, char *type); Index: libcg/src/api.c =================================================================== --- libcg.orig/src/api.c +++ libcg/src/api.c @@ -2241,7 +2241,7 @@ int cgroup_walk_tree_next(const int dept struct cgroup_file_info *info, int base_level) { int ret = 0; - FTS *fts = *(FTS **)handle; + struct cgroup_tree_handle *entry; FTSENT *ent; if (!cgroup_initialized) @@ -2249,26 +2249,34 @@ int cgroup_walk_tree_next(const int dept if (!handle) return ECGINVAL; - ent = fts_read(fts); + + entry = (struct cgroup_tree_handle *) *handle; + + ent = fts_read(entry->fts); if (!ent) return ECGEOF; if (!base_level && depth) base_level = ent->fts_level + depth; - ret = cg_walk_node(fts, ent, base_level, info); - *handle = fts; + ret = cg_walk_node(entry->fts, ent, base_level, info); + *handle = entry; return ret; } int cgroup_walk_tree_end(void **handle) { - FTS *fts = *(FTS **)handle; + struct cgroup_tree_handle *entry; if (!cgroup_initialized) return ECGROUPNOTINITIALIZED; if (!handle) return ECGINVAL; - fts_close(fts); + + entry = (struct cgroup_tree_handle *) *handle; + + fts_close(entry->fts); + free(entry); + *handle = NULL; return 0; } @@ -2285,31 +2293,63 @@ int cgroup_walk_tree_begin(char *control char full_path[FILENAME_MAX]; FTSENT *ent; FTS *fts; + struct cgroup_tree_handle *entry; if (!cgroup_initialized) return ECGROUPNOTINITIALIZED; + if (!handle) + return ECGINVAL; + if (!cg_build_path(base_path, full_path, controller)) return ECGOTHER; + entry = calloc(sizeof(struct cgroup_tree_handle), 1); + + if (!entry) { + last_errno = errno; + return ECGOTHER; + } + *base_level = 0; cg_path[0] = full_path; cg_path[1] = NULL; - fts = fts_open(cg_path, FTS_LOGICAL | FTS_NOCHDIR | + entry->fts = fts_open(cg_path, FTS_LOGICAL | FTS_NOCHDIR | FTS_NOSTAT, NULL); - ent = fts_read(fts); + ent = fts_read(entry->fts); if (!ent) { cgroup_dbg("fts_read failed\n"); return ECGINVAL; } if (!*base_level && depth) *base_level = ent->fts_level + depth; - ret = cg_walk_node(fts, ent, *base_level, info); - *handle = fts; + ret = cg_walk_node(entry->fts, ent, *base_level, info); + *handle = entry; return ret; } +int cgroup_walk_tree_set_flags(void **handle, int flags) +{ + struct cgroup_tree_handle *entry; + + if (!cgroup_initialized) + return ECGROUPNOTINITIALIZED; + + if (!handle) + return ECGINVAL; + + if ((flags & CGROUP_WALK_TYPE_PRE_DIR) && + (flags & CGROUP_WALK_TYPE_POST_DIR)) + return ECGINVAL; + + entry = (struct cgroup_tree_handle *) *handle; + entry->flags = flags; + + *handle = entry; + return 0; +} + /* * This parses a stat line which is in the form of (name value) pair * separated by a space. Index: libcg/include/libcgroup.h =================================================================== --- libcg.orig/include/libcgroup.h +++ libcg/include/libcgroup.h @@ -256,6 +256,16 @@ int cgroup_walk_tree_next(const int dept int cgroup_walk_tree_end(void **handle); /** + * This API is used to set the flags for walk_tree API. Currently availble + * flags are + * + * CGROUP_WALK_TYPE_PRE_DIR + * CGROUP_WALK_TYPE_POST_DIR + * + */ +int cgroup_walk_tree_set_flags(void **handle, int flags); + +/** * Read the statistics values for the specified controller * @controller: Name of the controller for which stats are requested. * @path: cgroup path. ------------------------------------------------------------------------------ Crystal Reports - New Free Runtime and 30 Day Trial Check out the new simplified licensing option that enables unlimited royalty-free distribution of the report engine for externally facing server and web deployment. http://p.sf.net/sfu/businessobjects _______________________________________________ Libcg-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/libcg-devel
