From d74c167420b1c2eba74b29cf13b87f1143951b19 Mon Sep 17 00:00:00 2001
From: David Steele <david@pgmasters.net>
Date: Sun, 29 Apr 2018 10:41:05 -0400
Subject: [PATCH] Add bufNewC() and only reallocate buffer when the size has
 changed.

---
 doc/xml/release.xml                     |  2 +-
 src/common/type/buffer.c                | 55 +++++++++++++++++--------
 src/common/type/buffer.h                |  1 +
 test/src/module/common/typeBufferTest.c |  9 +++-
 4 files changed, 47 insertions(+), 20 deletions(-)

diff --git a/doc/xml/release.xml b/doc/xml/release.xml
index 6abc40ad7..4fee28699 100644
--- a/doc/xml/release.xml
+++ b/doc/xml/release.xml
@@ -83,7 +83,7 @@
                     </release-item>
 
                     <release-item>
-                        <p>Add <code>bufEq</code> and <code>bufCat</code> to <code>Buffer</code> object.</p>
+                        <p>Improve <code>Buffer</code> object.  Add <code>bufNewC()</code>, <code>bufEq()</code> and <code>bufCat()</code>.  Only reallocate buffer when the size has changed.</p>
                     </release-item>
 
                     <release-item>
diff --git a/src/common/type/buffer.c b/src/common/type/buffer.c
index 88d4792c6..b7a3a62dd 100644
--- a/src/common/type/buffer.c
+++ b/src/common/type/buffer.c
@@ -40,6 +40,21 @@ bufNew(size_t size)
     return this;
 }
 
+/***********************************************************************************************************************************
+Create a new buffer from a C buffer
+***********************************************************************************************************************************/
+Buffer *
+bufNewC(size_t size, const void *buffer)
+{
+    // Create object
+    Buffer *this = bufNew(size);
+
+    // Copy the data
+    memcpy(this->buffer, buffer, this->size);
+
+    return this;
+}
+
 /***********************************************************************************************************************************
 Create a new buffer from a string
 ***********************************************************************************************************************************/
@@ -118,34 +133,38 @@ Resize the buffer
 Buffer *
 bufResize(Buffer *this, size_t size)
 {
-    // If new size is zero then free memory if allocated
-    if (size == 0)
+    // Only resize if it the new size is different
+    if (this->size != size)
     {
-        if (this->buffer != NULL)
+        // If new size is zero then free memory if allocated
+        if (size == 0)
         {
+            // When setting size down to 0 the buffer should always be allocated
+            ASSERT_DEBUG(this->buffer != NULL);
+
             MEM_CONTEXT_BEGIN(this->memContext)
             {
                 memFree(this->buffer);
             }
             MEM_CONTEXT_END();
-        }
 
-        this->buffer = NULL;
-        this->size = 0;
-    }
-    // Else allocate or resize
-    else
-    {
-        MEM_CONTEXT_BEGIN(this->memContext)
+            this->buffer = NULL;
+            this->size = 0;
+        }
+        // Else allocate or resize
+        else
         {
-            if (this->buffer == NULL)
-                this->buffer = memNew(size);
-            else
-                this->buffer = memGrowRaw(this->buffer, size);
-        }
-        MEM_CONTEXT_END();
+            MEM_CONTEXT_BEGIN(this->memContext)
+            {
+                if (this->buffer == NULL)
+                    this->buffer = memNew(size);
+                else
+                    this->buffer = memGrowRaw(this->buffer, size);
+            }
+            MEM_CONTEXT_END();
 
-        this->size = size;
+            this->size = size;
+        }
     }
 
     return this;
diff --git a/src/common/type/buffer.h b/src/common/type/buffer.h
index a44b99c5d..856f528ad 100644
--- a/src/common/type/buffer.h
+++ b/src/common/type/buffer.h
@@ -16,6 +16,7 @@ typedef struct Buffer Buffer;
 Functions
 ***********************************************************************************************************************************/
 Buffer *bufNew(size_t size);
+Buffer *bufNewC(size_t size, const void *buffer);
 Buffer *bufNewStr(const String *string);
 Buffer *bufCat(Buffer *this, const Buffer *cat);
 bool bufEq(const Buffer *this, const Buffer *compare);
diff --git a/test/src/module/common/typeBufferTest.c b/test/src/module/common/typeBufferTest.c
index 7a5c0c8a3..424d5a7d3 100644
--- a/test/src/module/common/typeBufferTest.c
+++ b/test/src/module/common/typeBufferTest.c
@@ -9,7 +9,7 @@ void
 testRun()
 {
     // *****************************************************************************************************************************
-    if (testBegin("bufNew(), bufNewStr(), bufMove(), bufSize(), bufPtr(), and bufFree()"))
+    if (testBegin("bufNew(), bugNewC, bufNewStr(), bufMove(), bufSize(), bufPtr(), and bufFree()"))
     {
         Buffer *buffer = NULL;
 
@@ -31,6 +31,12 @@ testRun()
         TEST_RESULT_VOID(bufFree(NULL), "free null buffer");
 
         TEST_RESULT_VOID(bufMove(NULL, NULL), "move null buffer");
+
+        // -------------------------------------------------------------------------------------------------------------------------
+        char cBuffer[] = "ABCD";
+
+        TEST_ASSIGN(buffer, bufNewC(sizeof(cBuffer), cBuffer), "create from c buffer");
+        TEST_RESULT_BOOL(memcmp(bufPtr(buffer), cBuffer, sizeof(cBuffer)) == 0, true, "check buffer");
     }
 
     // *****************************************************************************************************************************
@@ -52,6 +58,7 @@ testRun()
 
         // Increase buffer size
         TEST_ASSIGN(bufferPtr, bufPtr(bufResize(buffer, 512)), "increase buffer size");
+        TEST_ASSIGN(bufferPtr, bufPtr(bufResize(buffer, 512)), "set to same size");
         TEST_RESULT_INT(bufSize(buffer), 512, "check size");
 
         // Test that no bytes have changed in the original data