top: fix CPU% for thread display. Closes 4081

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

diff --git a/libbb/procps.c b/libbb/procps.c
index 1dea61518f31fc2a68d7d52ca625146d4cadd733..e15ddd1e5e1820d7d70eebd9d837780bcb3133f6 100644 (file)
--- a/libbb/procps.c
+++ b/libbb/procps.c
@@ -284,27 +284,25 @@ int FAST_FUNC procps_read_smaps(pid_t pid, struct smaprec *total,
 void BUG_comm_size(void);
 procps_status_t* FAST_FUNC procps_scan(procps_status_t* sp, int flags)
 {
-       struct dirent *entry;
-       char buf[PROCPS_BUFSIZE];
-       char filename[sizeof("/proc//cmdline") + sizeof(int)*3];
-       char *filename_tail;
-       long tasknice;
-       unsigned pid;
-       int n;
-       struct stat sb;
-
        if (!sp)
                sp = alloc_procps_scan();
 
        for (;;) {
+               struct dirent *entry;
+               char buf[PROCPS_BUFSIZE];
+               long tasknice;
+               unsigned pid;
+               int n;
+               char filename[sizeof("/proc/%u/task/%u/cmdline") + sizeof(int)*3 * 2];
+               char *filename_tail;
+
 #if ENABLE_FEATURE_SHOW_THREADS
-               if ((flags & PSSCAN_TASKS) && sp->task_dir) {
+               if (sp->task_dir) {
                        entry = readdir(sp->task_dir);
                        if (entry)
                                goto got_entry;
                        closedir(sp->task_dir);
                        sp->task_dir = NULL;
-                       sp->main_thread_pid = 0;
                }
 #endif
                entry = readdir(sp->dir);
@@ -321,9 +319,9 @@ procps_status_t* FAST_FUNC procps_scan(procps_status_t* sp, int flags)
                        /* We found another /proc/PID. Do not use it,
                         * there will be /proc/PID/task/PID (same PID!),
                         * so just go ahead and dive into /proc/PID/task. */
-                       char task_dir[sizeof("/proc/%u/task") + sizeof(int)*3];
-                       sprintf(task_dir, "/proc/%u/task", pid);
-                       sp->task_dir = xopendir(task_dir);
+                       sprintf(filename, "/proc/%u/task", pid);
+                       /* Note: if opendir fails, we just go to next /proc/XXX */
+                       sp->task_dir = opendir(filename);
                        sp->main_thread_pid = pid;
                        continue;
                }
@@ -347,9 +345,15 @@ procps_status_t* FAST_FUNC procps_scan(procps_status_t* sp, int flags)
                }
 #endif
 
-               filename_tail = filename + sprintf(filename, "/proc/%u/", pid);
+#if ENABLE_FEATURE_SHOW_THREADS
+               if (sp->task_dir)
+                       filename_tail = filename + sprintf(filename, "/proc/%u/task/%u/", sp->main_thread_pid, pid);
+               else
+#endif
+                       filename_tail = filename + sprintf(filename, "/proc/%u/", pid);
 
                if (flags & PSSCAN_UIDGID) {
+                       struct stat sb;
                        if (stat(filename, &sb))
                                continue; /* process probably exited */
                        /* Effective UID/GID, not real */