From 15b361fbac9b6a640116b25faad721085ac3adbe Mon Sep 17 00:00:00 2001
From: Deomid Ryabkov <rojer@cesanta.com>
Date: Fri, 23 Nov 2018 14:54:44 +0000
Subject: [PATCH] Add mbuf_clear()

PUBLISHED_FROM=754b98b3000b24ad3b3d9cc0b4c480ca005a1c3f
---
 docs/c-api/mbuf.h/intro.md      |  1 +
 docs/c-api/mbuf.h/mbuf_clear.md | 10 ++++++++++
 mongoose.c                      |  5 +++++
 mongoose.h                      |  3 +++
 4 files changed, 19 insertions(+)
 create mode 100644 docs/c-api/mbuf.h/mbuf_clear.md

diff --git a/docs/c-api/mbuf.h/intro.md b/docs/c-api/mbuf.h/intro.md
index 056369a2..5779ab9c 100644
--- a/docs/c-api/mbuf.h/intro.md
+++ b/docs/c-api/mbuf.h/intro.md
@@ -4,6 +4,7 @@ symbol_kind: "intro"
 decl_name: "mbuf.h"
 items:
   - { name: mbuf_append.md }
+  - { name: mbuf_clear.md }
   - { name: mbuf_free.md }
   - { name: mbuf_init.md }
   - { name: mbuf_insert.md }
diff --git a/docs/c-api/mbuf.h/mbuf_clear.md b/docs/c-api/mbuf.h/mbuf_clear.md
new file mode 100644
index 00000000..afefc21a
--- /dev/null
+++ b/docs/c-api/mbuf.h/mbuf_clear.md
@@ -0,0 +1,10 @@
+---
+title: "mbuf_clear()"
+decl_name: "mbuf_clear"
+symbol_kind: "func"
+signature: |
+  void mbuf_clear(struct mbuf *);
+---
+
+Removes all the data from mbuf (if any). 
+
diff --git a/mongoose.c b/mongoose.c
index 76f35fe3..d3cd2bd5 100644
--- a/mongoose.c
+++ b/mongoose.c
@@ -1620,6 +1620,11 @@ void mbuf_remove(struct mbuf *mb, size_t n) {
   }
 }
 
+void mbuf_clear(struct mbuf *mb) WEAK;
+void mbuf_clear(struct mbuf *mb) {
+  mb->len = 0;
+}
+
 #endif /* EXCLUDE_COMMON */
 #ifdef MG_MODULE_LINES
 #line 1 "common/mg_str.c"
diff --git a/mongoose.h b/mongoose.h
index 4b5b0db6..07cf98a1 100644
--- a/mongoose.h
+++ b/mongoose.h
@@ -2388,6 +2388,9 @@ void mbuf_remove(struct mbuf *, size_t data_size);
  */
 void mbuf_resize(struct mbuf *, size_t new_size);
 
+/* Removes all the data from mbuf (if any). */
+void mbuf_clear(struct mbuf *);
+
 /* Shrinks an Mbuf by resizing its `size` to `len`. */
 void mbuf_trim(struct mbuf *);