On Mar 31, 2011, at 9:48 PM, Mathieu Desnoyers wrote:
* Nils Carlson ([email protected]) wrote:
Changes since v1:
* Use list length, not the size in bytes
* Fix a possible bug for pid_t in a sscanf
* Use list length in the dir scanning function
Restructure the command to separate the pid gathering.
This will allow a root user to gather pid from multiple user
directories.
Signed-off-by: Nils Carlson <[email protected]>
---
libustctl/libustctl.c | 81 ++++++++++++++++++++++++++++++
+------------------
1 files changed, 51 insertions(+), 30 deletions(-)
diff --git a/libustctl/libustctl.c b/libustctl/libustctl.c
index d57e645..5625f43 100644
--- a/libustctl/libustctl.c
+++ b/libustctl/libustctl.c
@@ -88,53 +88,74 @@ int ustctl_connect_pid(pid_t pid)
return sock;
}
-pid_t *ustctl_get_online_pids(void)
+static void get_pids_in_dir(DIR *dir, pid_t **pid_list,
+ unsigned int *pid_list_size)
{
struct dirent *dirent;
- DIR *dir;
- unsigned int ret_size = 1 * sizeof(pid_t), i = 0;
-
- dir = opendir(SOCK_DIR);
- if (!dir) {
- return NULL;
- }
-
- pid_t *ret = (pid_t *) malloc(ret_size);
+ unsigned int read_pid;
while ((dirent = readdir(dir))) {
if (!strcmp(dirent->d_name, ".") ||
- !strcmp(dirent->d_name, "..")) {
+ !strcmp(dirent->d_name, "..") ||
+ !strcmp(dirent->d_name, "ust-consumer") ||
+ dirent->d_type == DT_DIR) {
continue;
}
- if (dirent->d_type != DT_DIR &&
- !!strcmp(dirent->d_name, "ust-consumer")) {
-
- sscanf(dirent->d_name, "%u", (unsigned int *) &ret[i]);
- /* FIXME: Here we previously called pid_is_online, which
- * always returned 1, now I replaced it with just 1.
- * We need to figure out an intelligent way of solving
- * this, maybe connect-disconnect.
- */
- if (1) {
- ret_size += sizeof(pid_t);
- ret = (pid_t *) realloc(ret, ret_size);
- ++i;
- }
+ sscanf(dirent->d_name, "%u", &read_pid);
+
+ (*pid_list)[*pid_list_size - 1] = read_pid;
+ /* FIXME: Here we previously called pid_is_online, which
+ * always returned 1, now I replaced it with just 1.
+ * We need to figure out an intelligent way of solving
+ * this, maybe connect-disconnect.
+ */
+ if (1) {
+ (*pid_list_size)++;
+ *pid_list = realloc(*pid_list,
+ *pid_list_size * sizeof(pid_t));
Rather than reallocating the memory space each time we add a single
entry, I would recommend to double the size each time we need to grow
the allocated space. We use a "0" entry at the end to denote the end
of
the list anyway, so allocating an area larger than needed should not
hurt, and it will turn this O(nb items) * mem allocation runtime cost
into a O(log(nb items)) * mem allocation runtime cost.
Yepp, can look at it. This just follows the pattern of the old code.
But nothing to say the old code was doing it right.
/Nils
Thanks,
Mathieu
}
}
- ret[i] = 0; /* Array end */
+ (*pid_list)[*pid_list_size - 1] = 0; /* Array end */
+}
- if (ret[0] == 0) {
- /* No PID at all */
- free(ret);
+pid_t *ustctl_get_online_pids(void)
+{
+ char *dir_name;
+ DIR *dir;
+ unsigned int pid_list_size = 1;
+ pid_t *pid_list = NULL;
+
+ dir_name = ustcomm_user_sock_dir();
+ if (!dir_name) {
return NULL;
}
+ dir = opendir(dir_name);
+ if (!dir) {
+ goto free_dir_name;
+ }
+
+ pid_list = malloc(pid_list_size * sizeof(pid_t));
+
+ get_pids_in_dir(dir, &pid_list, &pid_list_size);
+
+ if (pid_list[0] == 0) {
+ /* No PID at all */
+ free(pid_list);
+ pid_list = NULL;
+ goto close_dir;
+ }
+
+close_dir:
closedir(dir);
- return ret;
+
+free_dir_name:
+ free(dir_name);
+
+ return pid_list;
}
/**
--
1.7.1
_______________________________________________
ltt-dev mailing list
[email protected]
http://lists.casi.polymtl.ca/cgi-bin/mailman/listinfo/ltt-dev
--
Mathieu Desnoyers
Operating System Efficiency R&D Consultant
EfficiOS Inc.
http://www.efficios.com
_______________________________________________
ltt-dev mailing list
[email protected]
http://lists.casi.polymtl.ca/cgi-bin/mailman/listinfo/ltt-dev
_______________________________________________
ltt-dev mailing list
[email protected]
http://lists.casi.polymtl.ca/cgi-bin/mailman/listinfo/ltt-dev
