From de5c0a28fb02f1f62f1b9fff770dae8f8360278b Mon Sep 17 00:00:00 2001
From: Sage Weil <sage@redhat.com>
Date: Thu, 27 Apr 2017 16:38:20 -0400
Subject: [PATCH] buffer: templatize prepare_iov

Allow this to work on std::vector types.

Signed-off-by: Sage Weil <sage@redhat.com>
---
 src/common/buffer.cc | 13 -------------
 src/include/buffer.h | 14 +++++++++++++-
 2 files changed, 13 insertions(+), 14 deletions(-)

diff --git a/src/common/buffer.cc b/src/common/buffer.cc
index ae70a21c94f..957f5da8c56 100644
--- a/src/common/buffer.cc
+++ b/src/common/buffer.cc
@@ -2338,19 +2338,6 @@ int buffer::list::write_fd(int fd, uint64_t offset) const
   return 0;
 }
 
-void buffer::list::prepare_iov(std::vector<iovec> *piov) const
-{
-  assert(_buffers.size() <= IOV_MAX);
-  piov->resize(_buffers.size());
-  unsigned n = 0;
-  for (std::list<buffer::ptr>::const_iterator p = _buffers.begin();
-       p != _buffers.end();
-       ++p, ++n) {
-    (*piov)[n].iov_base = (void *)p->c_str();
-    (*piov)[n].iov_len = p->length();
-  }
-}
-
 int buffer::list::write_fd_zero_copy(int fd) const
 {
   if (!can_zero_copy())
diff --git a/src/include/buffer.h b/src/include/buffer.h
index 4d4942adaab..3a93091b83a 100644
--- a/src/include/buffer.h
+++ b/src/include/buffer.h
@@ -17,6 +17,7 @@
 #if defined(__linux__) || defined(__FreeBSD__)
 #include <stdlib.h>
 #endif
+#include <limits.h>
 
 #ifndef _XOPEN_SOURCE
 # define _XOPEN_SOURCE 600
@@ -867,7 +868,18 @@ namespace buffer CEPH_BUFFER_API {
     int write_fd(int fd) const;
     int write_fd(int fd, uint64_t offset) const;
     int write_fd_zero_copy(int fd) const;
-    void prepare_iov(std::vector<iovec> *piov) const;
+    template<typename VectorT>
+    void prepare_iov(VectorT *piov) const {
+      assert(_buffers.size() <= IOV_MAX);
+      piov->resize(_buffers.size());
+      unsigned n = 0;
+      for (std::list<buffer::ptr>::const_iterator p = _buffers.begin();
+	   p != _buffers.end();
+	   ++p, ++n) {
+	(*piov)[n].iov_base = (void *)p->c_str();
+	(*piov)[n].iov_len = p->length();
+      }
+    }
     uint32_t crc32c(uint32_t crc) const;
     void invalidate_crc();
   };
-- 
2.39.5