From 9cd9ab436d732662cd3145304388f70253f67f1d Mon Sep 17 00:00:00 2001
From: Jianhui Zhao <jianhuizhao329@gmail.com>
Date: Mon, 8 Oct 2018 22:10:05 +0800
Subject: [PATCH] Update buffer from 'github/zhaojh329/buffer'

Signed-off-by: Jianhui Zhao <jianhuizhao329@gmail.com>
---
 src/buffer.c |  6 +++++-
 src/buffer.h | 23 ++++++++++++++++++++++-
 2 files changed, 27 insertions(+), 2 deletions(-)

diff --git a/src/buffer.c b/src/buffer.c
index c52df68..8684c0b 100644
--- a/src/buffer.c
+++ b/src/buffer.c
@@ -23,7 +23,6 @@
 
 #include <stdlib.h>
 #include <string.h>
-#include <unistd.h>
 #include <stdio.h>
 #include <errno.h>
 #include <limits.h>
@@ -109,6 +108,7 @@ void *buffer_put(struct buffer *b, size_t len)
 
     tmp = b->tail;
     b->tail += len;
+
     return tmp;
 }
 
@@ -230,6 +230,8 @@ size_t buffer_pull(struct buffer *b, void *dest, size_t len)
 
     b->data += len;
 
+    buffer_check_persistent_size(b);
+
     return len;
 }
 
@@ -283,6 +285,8 @@ int buffer_pull_to_fd(struct buffer *b, int fd, size_t len,
         b->data += ret;
     } while (remain);
 
+    buffer_check_persistent_size(b);
+
     return len - remain;
 }
 
diff --git a/src/buffer.h b/src/buffer.h
index fc74992..0d0dd08 100644
--- a/src/buffer.h
+++ b/src/buffer.h
@@ -23,6 +23,7 @@
 #include <stdint.h>
 #include <stdarg.h>
 #include <string.h>
+#include <unistd.h>
 #include <stdbool.h>
 #include <sys/types.h>
 
@@ -46,6 +47,7 @@ enum {
 };
 
 struct buffer {
+    size_t persistent; /* persistent size */
     uint8_t *head;  /* Head of buffer */
     uint8_t *data;  /* Data head pointer */
     uint8_t *tail;  /* Data tail pointer */
@@ -84,6 +86,23 @@ static inline void *buffer_data(const struct buffer *b)
     return b->data;
 }
 
+static inline void buffer_set_persistent_size(struct buffer *b, size_t size)
+{
+    size_t new_size = getpagesize();
+
+    while (new_size < size)
+        new_size <<= 1;
+
+    b->persistent = new_size;
+}
+
+static inline void buffer_check_persistent_size(struct buffer *b)
+{
+    if (b->persistent > 0 &&
+        buffer_size(b) > b->persistent && buffer_length(b) < b->persistent)
+        buffer_resize(b, b->persistent);
+}
+
 void *buffer_put(struct buffer *b, size_t len);
 
 static inline void *buffer_put_zero(struct buffer *b, size_t len)
@@ -182,8 +201,10 @@ int buffer_put_fd(struct buffer *b, int fd, ssize_t len, bool *eof,
  */
 static inline void buffer_truncate(struct buffer *b, size_t len)
 {
-    if (buffer_length(b) > len)
+    if (buffer_length(b) > len) {
         b->tail = b->data + len;
+        buffer_check_persistent_size(b);
+    }
 }