From c85703bdcc44833a214aba1f091301c789156d24 Mon Sep 17 00:00:00 2001
From: Yijie Shen <henry.yijieshen@gmail.com>
Date: Wed, 1 May 2024 14:22:50 -0700
Subject: [PATCH] feat: rename with overwrite option

fix to match java signature
---
 c_src/libhdfs/hdfs.c | 77 ++++++++++++++++++++++++++++++++++++++++++++
 c_src/libhdfs/hdfs.h | 10 ++++++
 src/hdfs.rs          |  8 +++--
 3 files changed, 93 insertions(+), 2 deletions(-)

diff --git a/c_src/libhdfs/hdfs.c b/c_src/libhdfs/hdfs.c
index 7f36775..34ae654 100644
--- a/c_src/libhdfs/hdfs.c
+++ b/c_src/libhdfs/hdfs.c
@@ -42,6 +42,7 @@
 #define JAVA_NET_URI    "java/net/URI"
 #define JAVA_STRING     "java/lang/String"
 #define READ_OPTION     "org/apache/hadoop/fs/ReadOption"
+#define RENAME_OPTION   "org/apache/hadoop/fs/Options$Rename"
 
 #define JAVA_VOID       "V"
 
@@ -2025,6 +2026,82 @@ int hdfsRename(hdfsFS fs, const char *oldPath, const char *newPath)
     return ret;
 }
 
+int hdfsRenameOverwrite(hdfsFS fs, const char *oldPath, const char *newPath)
+{
+    // JAVA EQUIVALENT:
+    //  Path old = new Path(oldPath);
+    //  Path new = new Path(newPath);
+    //  fs.rename(old, new, overwrite = true);
+
+    jobject jFS = (jobject)fs;
+    jthrowable jthr;
+    jobject jOldPath = NULL, jNewPath = NULL;
+    int ret = -1;
+    jvalue jVal;
+    jobject enumInst = NULL, enumSetObj = NULL;
+
+    //Get the JNIEnv* corresponding to current thread
+    JNIEnv* env = getJNIEnv();
+    if (env == NULL) {
+      errno = EINTERNAL;
+      return -1;
+    }
+
+    jthr = fetchEnumInstance(env, RENAME_OPTION,
+              "OVERWRITE", &enumInst);
+    if (jthr) {
+        errno = printExceptionAndFree(env, jthr, PRINT_EXC_ALL,
+            "hdfsRename: fetchEnumInstance(" RENAME_OPTION ", OVERWRITE)");
+        goto done;
+    }
+    jthr = invokeMethod(env, &jVal, STATIC, NULL,
+            "java/util/EnumSet", "of",
+            "(Ljava/lang/Enum;)Ljava/util/EnumSet;", enumInst);
+    if (jthr) {
+        goto done;
+    }
+    enumSetObj = jVal.l;
+
+    jclass enumSetClass = (*env)->FindClass(env, "java/util/EnumSet");
+    jmethodID toArrayTypedMethodID = (*env)->GetMethodID(env, enumSetClass, "toArray", "([Ljava/lang/Object;)[Ljava/lang/Object;");
+    jclass renameOptionClass = (*env)->FindClass(env, "org/apache/hadoop/fs/Options$Rename");
+    jobjectArray typedArray = (*env)->NewObjectArray(env, 1, renameOptionClass, NULL);
+    jobjectArray enumArray = (jobjectArray)(*env)->CallObjectMethod(env, enumSetObj, toArrayTypedMethodID, typedArray);
+
+    jthr = constructNewObjectOfPath(env, oldPath, &jOldPath);
+    if (jthr) {
+        errno = printExceptionAndFree(env, jthr, PRINT_EXC_ALL,
+            "hdfsRename: constructNewObjectOfPath(%s)", oldPath);
+        goto done;
+    }
+    jthr = constructNewObjectOfPath(env, newPath, &jNewPath);
+    if (jthr) {
+        errno = printExceptionAndFree(env, jthr, PRINT_EXC_ALL,
+            "hdfsRename: constructNewObjectOfPath(%s)", newPath);
+        goto done;
+    }
+
+    // Rename the file
+    // TODO: use rename2 here?  (See HDFS-3592)
+    jthr = invokeMethod(env, &jVal, INSTANCE, jFS, HADOOP_FS, "rename",
+                     "(Lorg/apache/hadoop/fs/Path;Lorg/apache/hadoop/fs/Path;[Lorg/apache/hadoop/fs/Options$Rename;)V",
+                     jOldPath, jNewPath, enumArray);
+    if (jthr) {
+        errno = printExceptionAndFree(env, jthr, PRINT_EXC_ALL,
+            "hdfsRename(oldPath=%s, newPath=%s): FileSystem#rename",
+            oldPath, newPath);
+        goto done;
+    }
+    ret = 0;
+
+done:
+    destroyLocalReference(env, jOldPath);
+    destroyLocalReference(env, jNewPath);
+    destroyLocalReference(env, enumInst);
+    destroyLocalReference(env, enumSetObj);
+    return ret;
+}
+
 
 
 char* hdfsGetWorkingDirectory(hdfsFS fs, char* buffer, size_t bufferSize)
diff --git a/c_src/libhdfs/hdfs.h b/c_src/libhdfs/hdfs.h
index 267ca59..88f99bf 100644
--- a/c_src/libhdfs/hdfs.h
+++ b/c_src/libhdfs/hdfs.h
@@ -712,6 +712,16 @@ extern  "C" {
     LIBHDFS_EXTERNAL
     int hdfsRename(hdfsFS fs, const char* oldPath, const char* newPath);
 
+    /**
+     * hdfsRename - Rename file and overwrite if exists.
+     * @param fs The configured filesystem handle.
+     * @param oldPath The path of the source file.
+     * @param newPath The path of the destination file.
+     * @return Returns 0 on success, -1 on error.
+     */
+    LIBHDFS_EXTERNAL
+    int hdfsRenameOverwrite(hdfsFS fs, const char* oldPath, const char* newPath);
+
 
     /** 
      * hdfsGetWorkingDirectory - Get the current working directory for
diff --git a/src/hdfs.rs b/src/hdfs.rs
index 73c5269..d5b6a67 100644
--- a/src/hdfs.rs
+++ b/src/hdfs.rs
@@ -440,11 +440,15 @@ impl HdfsFs {
     }
 
     /// Rename file.
-    pub fn rename(&self, old_path: &str, new_path: &str) -> Result<bool, HdfsErr> {
+    pub fn rename(&self, old_path: &str, new_path: &str, overwrite: bool) -> Result<bool, HdfsErr> {
         if unsafe {
             let cstr_old_path = CString::new(old_path).unwrap();
             let cstr_new_path = CString::new(new_path).unwrap();
-            hdfsRename(self.raw, cstr_old_path.as_ptr(), cstr_new_path.as_ptr())
+            if overwrite {
+                hdfsRenameOverwrite(self.raw, cstr_old_path.as_ptr(), cstr_new_path.as_ptr())
+            } else {
+                hdfsRename(self.raw, cstr_old_path.as_ptr(), cstr_new_path.as_ptr())
+            }
         } == 0
         {
             Ok(true)