Replace some deprecated usages of readdir_r with readdir

sandbox/linux/services/proc_util.cc

Index: sandbox/linux/services/proc_util.cc
diff --git a/sandbox/linux/services/proc_util.cc b/sandbox/linux/services/proc_util.cc
index b6d58de56489f7f0a92984ee079c623c7cdfabc6..73f8daa5c0eedb9bd354eb564220fac3af006c49 100644
--- a/sandbox/linux/services/proc_util.cc
+++ b/sandbox/linux/services/proc_util.cc
@@ -51,15 +51,13 @@ int ProcUtil::CountOpenFds(int proc_fd) {
   CHECK(dir);
 
   int count = 0;
-  struct dirent e;
-  struct dirent* de;
-  while (!readdir_r(dir.get(), &e, &de) && de) {
-    if (strcmp(e.d_name, ".") == 0 || strcmp(e.d_name, "..") == 0) {
+  for (struct dirent* e = readdir(dir.get()); e; e = readdir(dir.get())) {

[Jorge Lucangeli Obes, 2016/10/19 15:50:16]

Are these calls to readdir guaranteed to not race each other? What happens if
more than one thread in the same process is using proc_util.cc?

[dcheng, 2016/10/19 22:11:39]

My understanding (and the condition on which I LGTMed the base changes) is that
readdir's on "different directory streams" are safe, even if simultaneously
called.

Since the directory stream is scoped to just this function, in theory, it should
be OK.

+    if (strcmp(e->d_name, ".") == 0 || strcmp(e->d_name, "..") == 0) {
       continue;
     }
 
     int fd_num;
-    CHECK(base::StringToInt(e.d_name, &fd_num));
+    CHECK(base::StringToInt(e->d_name, &fd_num));
     if (fd_num == proc_fd || fd_num == proc_self_fd) {
       continue;
     }
@@ -81,22 +79,20 @@ bool ProcUtil::HasOpenDirectory(int proc_fd) {
   ScopedDIR dir(fdopendir(proc_self_fd));
   CHECK(dir);
 
-  struct dirent e;
-  struct dirent* de;
-  while (!readdir_r(dir.get(), &e, &de) && de) {
-    if (strcmp(e.d_name, ".") == 0 || strcmp(e.d_name, "..") == 0) {
+  for (struct dirent *e = readdir(dir.get()); e; e = readdir(dir.get())) {
+    if (strcmp(e->d_name, ".") == 0 || strcmp(e->d_name, "..") == 0) {
       continue;
     }
 
     int fd_num;
-    CHECK(base::StringToInt(e.d_name, &fd_num));
+    CHECK(base::StringToInt(e->d_name, &fd_num));
     if (fd_num == proc_fd || fd_num == proc_self_fd) {
       continue;
     }
 
     struct stat s;
     // It's OK to use proc_self_fd here, fstatat won't modify it.
-    CHECK(fstatat(proc_self_fd, e.d_name, &s, 0) == 0);
+    CHECK(fstatat(proc_self_fd, e->d_name, &s, 0) == 0);
     if (S_ISDIR(s.st_mode)) {
       return true;
     }