Merge branch 'master' of ssh://balbir_singh@libcg.git.sourceforge.net/gitroot/libcg

5 files changed, 147 insertions, 3 deletions

diff --git a/include/libcgroup.h b/include/libcgroup.h
index efa852b..085c17a 100644
--- a/include/libcgroup.h
+++ b/include/libcgroup.h
@@ -274,6 +274,25 @@ int cgroup_read_stats_next(void **handle, struct cgroup_stat *stat);
 
 int cgroup_read_stats_end(void **handle);
 
+/**
+ * Read the tasks file to get the list of tasks in a cgroup
+ * @cgroup: Name of the cgroup
+ * @controller: Name of the cgroup subsystem
+ * @handle: Handle to be used in the iteration
+ * @pid: The pid read from the tasks file. Will be filled in by the API
+ */
+int cgroup_get_task_begin(char *cgroup, char *controller, void **handle,
+								pid_t *pid);
+
+/**
+ * Read the next task value
+ * @handle: The handle used for iterating
+ * @pid: The variable where the value will be stored
+ *
+ * return ECGEOF when the iterator finishes getting the list of tasks.
+ */
+int cgroup_get_task_next(void *handle, pid_t *pid);
+int cgroup_get_task_end(void **handle);
 /* The wrappers for filling libcg structures */
 
 struct cgroup *cgroup_new_cgroup(const char *name);
diff --git a/src/api.c b/src/api.c
index 4d5b524..baeb856 100644
--- a/src/api.c
+++ b/src/api.c
@@ -2407,3 +2407,71 @@ int cgroup_read_stats_begin(char *controller, char *path, void **handle,
 	*handle = fp;
 	return ret;
 }
+
+int cgroup_get_task_end(void **handle)
+{
+	if (!cgroup_initialized)
+		return ECGROUPNOTINITIALIZED;
+
+	if (!*handle)
+		return ECGINVAL;
+
+	fclose((FILE *) *handle);
+	*handle = NULL;
+
+	return 0;
+}
+
+int cgroup_get_task_next(void *handle, pid_t *pid)
+{
+	int ret;
+
+	if (!cgroup_initialized)
+		return ECGROUPNOTINITIALIZED;
+
+	if (!handle)
+		return ECGINVAL;
+
+	ret = fscanf((FILE *) handle, "%u", pid);
+
+	if (ret != 1) {
+		if (ret == EOF)
+			return ECGEOF;
+		last_errno = errno;
+		return ECGOTHER;
+	}
+
+	return 0;
+}
+
+int cgroup_get_task_begin(char *cgroup, char *controller, void **handle,
+								pid_t *pid)
+{
+	int ret = 0;
+	char path[FILENAME_MAX];
+	char *fullpath = NULL;
+
+	if (!cgroup_initialized)
+		return ECGROUPNOTINITIALIZED;
+
+	if (!cg_build_path(cgroup, path, controller))
+		return ECGOTHER;
+
+	ret = asprintf(&fullpath, "%s/tasks", path);
+
+	if (ret < 0) {
+		last_errno = errno;
+		return ECGOTHER;
+	}
+
+	*handle = (void *) fopen(fullpath, "r");
+	free(fullpath);
+
+	if (!*handle) {
+		last_errno = errno;
+		return ECGOTHER;
+	}
+	ret = cgroup_get_task_next(*handle, pid);
+
+	return ret;
+}
diff --git a/src/libcgroup.map b/src/libcgroup.map
index dd44fd7..4b95daa 100644
--- a/src/libcgroup.map
+++ b/src/libcgroup.map
@@ -52,8 +52,14 @@ global:
 	cgroup_walk_tree_begin;
 	cgroup_walk_tree_next;
 	cgroup_walk_tree_end;
+} CGROUP_0.32.1;
+
+CGROUP_0.34 {
+global:
+	cgroup_get_task_begin;
+	cgroup_get_task_end;
+	cgroup_get_task_next;
 	cgroup_read_stats_begin;
 	cgroup_read_stats_next;
 	cgroup_read_stats_end;
-} CGROUP_0.32.1;
-
+} CGROUP_0.33;
diff --git a/tests/Makefile.am b/tests/Makefile.am
index 5999389..41aebd3 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -2,7 +2,7 @@ INCLUDES = -I$(top_srcdir)/include
 LDADD = $(top_srcdir)/src/.libs/libcgroup.la
 
 # compile the tests, but do not install them
-noinst_PROGRAMS = libcgrouptest01 libcg_ba setuid pathtest walk_test read_stats
+noinst_PROGRAMS = libcgrouptest01 libcg_ba setuid pathtest walk_test read_stats walk_task
 
 libcgrouptest01_SOURCES=libcgrouptest01.c test_functions.c libcgrouptest.h
 libcg_ba_SOURCES=libcg_ba.cpp
@@ -10,6 +10,7 @@ setuid_SOURCES=setuid.c
 pathtest_SOURCES=pathtest.c
 walk_test_SOURCES=walk_test.c
 read_stats_SOURCES=read_stats.c
+walk_task_SOURCES=walk_task.c
 
 EXTRA_DIST = pathtest.sh runlibcgrouptest.sh
 
diff --git a/tests/walk_task.c b/tests/walk_task.c
new file mode 100644
index 0000000..fb89963
--- /dev/null
+++ b/tests/walk_task.c
@@ -0,0 +1,50 @@
+#include <stdio.h>
+#include <libcgroup.h>
+#include <stdlib.h>
+#include <string.h>
+#include <errno.h>
+
+int main(int argc, char *argv[])
+{
+	int ret, i;
+	char *group = NULL;
+	FILE *tasks = NULL;
+
+	if (argc < 2) {
+		printf("No list of groups provided\n");
+		return -1;
+	}
+
+	ret = cgroup_init();
+
+	if (ret) {
+		printf("cgroup_init failed with %s\n", cgroup_strerror(ret));
+		return -1;
+	}
+
+	for (i = 1; i < argc; i++) {
+		pid_t pid;
+		group = strdup(argv[i]);
+		printf("Printing the details of groups %s\n", group);
+		ret = cgroup_get_task_begin(group, "cpu", (void *) &tasks,
+									&pid);
+		while (!ret) {
+			printf("Pid is %u\n", pid);
+			ret = cgroup_get_task_next((void *) tasks, &pid);
+			if (ret && ret != ECGEOF) {
+				printf("cgroup_get_task_next failed with %s\n",
+							cgroup_strerror(ret));
+				if (ret == ECGOTHER)
+					printf("failure with %s\n",
+							strerror(errno));
+				return -1;
+			}
+		}
+		free(group);
+		group = NULL;
+		ret = cgroup_get_task_end((void **) &tasks);
+	}
+
+	return 0;
+
+}