8202794: Native Unix code should use readdir rather than readdir_r

Reviewed-by: alanb, bsrbnd

src/java.base/unix/native/libjava/TimeZone_md.c

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1999, 2016, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1999, 2018, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -52,7 +52,7 @@
 
 #if defined(_ALLBSD_SOURCE)
 #define dirent64 dirent
-#define readdir64_r readdir_r
+#define readdir64 readdir
 #endif
 
 #if !defined(__solaris__) || defined(__sparcv9) || defined(amd64)
@@ -122,32 +122,18 @@ findZoneinfoFile(char *buf, size_t size, const char *dir)
     DIR *dirp = NULL;
     struct stat statbuf;
     struct dirent64 *dp = NULL;
-    struct dirent64 *entry = NULL;
     char *pathname = NULL;
     int fd = -1;
     char *dbuf = NULL;
     char *tz = NULL;
     int res;
-    long name_max = 0;
 
     dirp = opendir(dir);
     if (dirp == NULL) {
         return NULL;
     }
 
-    name_max = pathconf(dir, _PC_NAME_MAX);
-    // If pathconf did not work, fall back to a mimimum buffer size.
-    if (name_max < 1024) {
-        name_max = 1024;
-    }
-
-    entry = (struct dirent64 *)malloc(offsetof(struct dirent64, d_name) + name_max + 1);
-    if (entry == NULL) {
-        (void) closedir(dirp);
-        return NULL;
-    }
-
-    while (readdir64_r(dirp, entry, &dp) == 0 && dp != NULL) {
+    while ((dp = readdir64(dirp)) != NULL) {
         /*
          * Skip '.' and '..' (and possibly other .* files)
          */
@@ -214,9 +200,6 @@ findZoneinfoFile(char *buf, size_t size, const char *dir)
         pathname = NULL;
     }
 
-    if (entry != NULL) {
-        free((void *) entry);
-    }
     if (dirp != NULL) {
         (void) closedir(dirp);
     }

src/java.base/unix/native/libjava/UnixFileSystem_md.c

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1998, 2017, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1998, 2018, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -65,7 +65,7 @@
 
 #if defined(_ALLBSD_SOURCE)
   #define dirent64 dirent
-  #define readdir64_r readdir_r
+  #define readdir64 readdir
   #define stat64 stat
   #ifndef MACOSX
     #define statvfs64 statvfs
@@ -312,7 +312,6 @@ Java_java_io_UnixFileSystem_list(JNIEnv *env, jobject this,
 {
     DIR *dir = NULL;
     struct dirent64 *ptr;
-    struct dirent64 *result;
     int len, maxlen;
     jobjectArray rv, old;
     jclass str_class;
@@ -325,13 +324,6 @@ Java_java_io_UnixFileSystem_list(JNIEnv *env, jobject this,
     } END_PLATFORM_STRING(env, path);
     if (dir == NULL) return NULL;
 
-    ptr = malloc(sizeof(struct dirent64) + (PATH_MAX + 1));
-    if (ptr == NULL) {
-        JNU_ThrowOutOfMemoryError(env, "heap allocation failed");
-        closedir(dir);
-        return NULL;
-    }
-
     /* Allocate an initial String array */
     len = 0;
     maxlen = 16;
@@ -339,7 +331,7 @@ Java_java_io_UnixFileSystem_list(JNIEnv *env, jobject this,
     if (rv == NULL) goto error;
 
     /* Scan the directory */
-    while ((readdir64_r(dir, ptr, &result) == 0)  && (result != NULL)) {
+    while ((ptr = readdir64(dir)) != NULL) {
         jstring name;
         if (!strcmp(ptr->d_name, ".") || !strcmp(ptr->d_name, ".."))
             continue;
@@ -360,7 +352,6 @@ Java_java_io_UnixFileSystem_list(JNIEnv *env, jobject this,
         (*env)->DeleteLocalRef(env, name);
     }
     closedir(dir);
-    free(ptr);
 
     /* Copy the final results into an appropriately-sized array */
     old = rv;
@@ -375,7 +366,6 @@ Java_java_io_UnixFileSystem_list(JNIEnv *env, jobject this,
 
  error:
     closedir(dir);
-    free(ptr);
     return NULL;
 }
 

src/jdk.management/unix/native/libmanagement_ext/OperatingSystemImpl.c

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2003, 2015, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2003, 2018, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -74,19 +74,9 @@ static jlong page_size = 0;
 
 #endif /* _ALLBSD_SOURCE */
 
-static struct dirent* read_dir(DIR* dirp, struct dirent* entry) {
-#ifdef __solaris__
-    struct dirent* dbuf = readdir(dirp);
-    return dbuf;
-#else /* __linux__ || _ALLBSD_SOURCE */
-    struct dirent* p;
-    if (readdir_r(dirp, entry, &p) == 0) {
-        return p;
-    } else {
-        return NULL;
-    }
+#if defined(_ALLBSD_SOURCE)
+  #define readdir64 readdir
 #endif
-}
 
 // true = get available swap in bytes
 // false = get total swap in bytes
@@ -432,7 +422,6 @@ Java_com_sun_management_internal_OperatingSystemImpl_getOpenFileDescriptorCount0
     return (100);
 #else /* solaris/linux */
     DIR *dirp;
-    struct dirent dbuf;
     struct dirent* dentp;
     jlong fds = 0;
 
@@ -453,7 +442,7 @@ Java_com_sun_management_internal_OperatingSystemImpl_getOpenFileDescriptorCount0
 
     // iterate through directory entries, skipping '.' and '..'
     // each entry represents an open file descriptor.
-    while ((dentp = read_dir(dirp, &dbuf)) != NULL) {
+    while ((dentp = readdir64(dirp)) != NULL) {
         if (isdigit(dentp->d_name[0])) {
             fds++;
         }