epics/pvData
0
0
Fork 0
Code Issues Pull Requests Projects Wiki Activity

overhaul byteBuffer implementation

Browse Source 
align(n) now fills skipped bytes with '\0'.

align(n,f) to choose a different fill value.

No other changes intended

Use intrinsic byte order swapping builtins for gcc, clang, and msvc.

use assert() to check pre/post conditions.

Remove unused condition macros and unreachable code.

Add tests of byte swapping primitives and
test the correctness of unaligned operations.

add illustrations of flip() and rewind()
This commit is contained in:
Michael Davidsaver
2015-12-30 16:22:08 -05:00
parent cc91e22038
commit a9111d78d3
2 changed files with 278 additions and 403 deletions
Download Patch File Download Diff File Expand all files Collapse all files

101
testApp/misc/testByteBuffer.cpp
View File

@@ -12,6 +12,7 @@
#include <iostream>
#include <fstream>
#include <cstring>
#include <memory>
#include <epicsUnitTest.h>
#include <testMain.h>
@@ -23,11 +24,12 @@ using namespace epics::pvData;
using std::string;
using std::cout;
static
void testBasicOperations() {
std::auto_ptr<ByteBuffer> buff(new ByteBuffer(32));
ByteBuffer* buff = new ByteBuffer(32);
testOk1(buff->getSize()==32);
// testOk1(buff->getByteOrder()==EPICS_BYTE_ORDER);
testOk1(buff->getPosition()==0);
testOk1(buff->getLimit()==32);
testOk1(buff->getRemaining()==32);
@@ -70,18 +72,6 @@ void testBasicOperations() {
testOk1(buff->getLong(8)==2345678123LL);
testOk1(buff->getFloat(16)==testFloat);
testOk1(buff->getDouble(20)==testDouble);
/*
std::size_t sp = buff->getPosition();
buff->setPosition(0);
testOk1(buff->getBoolean()==true);
testOk1(buff->getByte()==-12);
testOk1(buff->getShort()==10516);
testOk1(buff->getInt()==0x1937628B);
testOk1(buff->getLong()==2345678123LL);
testOk1(buff->getFloat()==testFloat);
testOk1(buff->getDouble()==testDouble);
buff->setPosition(sp);
*/
buff->flip();
testOk1(buff->getLimit()==28);
@@ -134,19 +124,7 @@ void testBasicOperations() {
buff->putLong(8, 2345678123LL);
buff->putFloat(16, testFloat);
buff->putDouble(20, testDouble);
/*
buff->clear();
buff->setPosition(28);
sp = buff->getPosition();
buff->putBoolean(true);
buff->putByte(-12);
buff->putShort(10516);
buff->putInt(0x1937628B);
buff->putLong(2345678123LL);
buff->putFloat(testFloat);
buff->putDouble(testDouble);
buff->setPosition(sp);
*/
buff->flip();
testOk1(buff->getLimit()==28);
testOk1(buff->getPosition()==0);
@@ -197,19 +175,19 @@ void testBasicOperations() {
testOk1(buff->getPosition()==6);
testOk1(strncmp(&src[2],&dst[2],6)==0);
cout<<" First 10 characters of destination: >>"<<string(dst, 10)<<"<<\n";
delete buff;
cout<<"# First 10 characters of destination: >>"<<string(dst, 10)<<"<<\n";
}
static
void testInverseEndianness() {
testDiag("check byte swapping features");
#if EPICS_BYTE_ORDER==EPICS_ENDIAN_BIG
ByteBuffer* buff = new ByteBuffer(32,EPICS_ENDIAN_LITTLE);
std::auto_ptr<ByteBuffer> buf(new ByteBuffer(32,EPICS_ENDIAN_LITTLE));
char refBuffer[] =
{ (char)0x02, (char)0x01, (char)0x0D, (char)0x0C, (char)0x0B, (char)0x0A};
#else
std::auto_ptr<ByteBuffer> buf(new ByteBuffer(32,EPICS_ENDIAN_BIG));
ByteBuffer* buff = new ByteBuffer(32, EPICS_ENDIAN_BIG);
char refBuffer[] = { (char)0x01, (char)0x02, (char)0x0A, (char)0x0B,
(char)0x0C, (char)0x0D };
@@ -224,15 +202,70 @@ void testInverseEndianness() {
testOk1(buff->getShort()==0x0102);
testOk1(buff->getInt()==0x0A0B0C0D);
}
delete buff;
static
void testSwap()
{
testDiag("Check epics::pvData::swap<T>(v)");
testOk1(swap<uint8>(0x80)==0x80);
testOk1(swap<uint16>(0x7080)==0x8070);
testOk1(swap<uint32>(0x10203040)==0x40302010);
uint64 a = 0x10203040,
b = 0x80706050;
a <<= 32;
b <<= 32;
a |= 0x50607080;
b |= 0x40302010;
testOk1(swap<uint64>(a)==b);
}
static
void testUnaligned()
{
testDiag("test correctness of unaligned access");
ByteBuffer buf(32, EPICS_ENDIAN_BIG);
// malloc() should give us a buffer aligned to at least native integer size
buf.align(sizeof(int));
testOk1(buf.getPosition()==0);
buf.clear();
buf.put<uint8>(0x42);
buf.put<uint16>(0x1020);
buf.align(2, '\x41');
testOk1(buf.getPosition()==4);
testOk1(memcmp(buf.getBuffer(), "\x42\x10\x20\x41", 4)==0);
buf.clear();
buf.put<uint8>(0x42);
buf.put<uint32>(0x12345678);
buf.align(4, '\x41');
testOk1(buf.getPosition()==8);
testOk1(memcmp(buf.getBuffer(), "\x42\x12\x34\x56\x78\x41\x41\x41", 8)==0);
buf.clear();
buf.put<uint8>(0x42);
uint64 val = 0x12345678;
val<<=32;
val |= 0x90abcdef;
buf.put<uint64>(val);
buf.align(8, '\x41');
testOk1(buf.getPosition()==16);
testOk1(memcmp(buf.getBuffer(), "\x42\x12\x34\x56\x78\x90\xab\xcd\xef\x41\x41\x41", 8)==0);
}
MAIN(testByteBuffer)
{
testPlan(82);
testPlan(93);
testDiag("Tests byteBuffer");
testBasicOperations();
testInverseEndianness();
testSwap();
testUnaligned();
return testDone();
}