josh/jes
1
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

add GapBuffer::copy_to()

Browse Source
This commit is contained in:
Josh Holtrop 2017-01-09 22:05:43 -05:00
parent 5de13644de
commit b9313ad606
2 changed files with 47 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

34
src/core/GapBuffer.h
View File

@ -99,6 +99,40 @@ public:
move_gap(m_size);
}
/**
* Copy a range of data from this GapBuffer to another.
*
* @param source_position
* Position in the gap buffer containing the data to copy.
* @param length
* Length of the data to copy.
* @param other
* Destination GapBuffer to copy the data into.
* @param destination_position
* Position in the destination GapBuffer to copy the data to.
*/
void copy_to(size_t source_position, size_t length, GapBuffer & other, size_t destination_position)
{
if ((source_position < m_size) &&
(length > 0u) &&
((source_position + length) <= m_size))
{
if ((m_gap_position <= source_position) ||
(m_gap_position >= (source_position + length)))
{
/* The gap is before or after the range of data to copy. */
other.insert(destination_position, address(source_position), length);
}
else
{
/* The gap is in the middle of the range of data to copy. */
size_t pre_gap_size = m_gap_position - source_position;
other.insert(destination_position, address(source_position), pre_gap_size);
other.insert(destination_position + pre_gap_size, address(source_position + pre_gap_size), length - pre_gap_size);
}
}
}
protected:
/** Address of the allocated memory buffer. */
uint8_t * m_buffer;

13
test/src/test_GapBuffer.cc
View File

@ -86,3 +86,16 @@ TEST(GapBufferTest, allocates_more_memory_and_copies_buffer_contents_when_needed
s += "EFGH";
EXPECT_EQ(s, gp.get_string());
}
TEST(GapBufferTest, allows_copying_data_range_from_one_gap_buffer_to_another)
{
GapBuffer gp1, gp2;
gp1.insert(0u, (const uint8_t *)"ABCDEFGH", 8u);
gp1.copy_to(0u, 4u, gp2, 0u);
EXPECT_EQ("ABCD", gp2.get_string());
gp1.insert(0u, (const uint8_t *)"IJKL", 4u);
gp1.copy_to(8u, 2u, gp2, 0u);
EXPECT_EQ("EFABCD", gp2.get_string());
gp1.copy_to(2u, 4u, gp2, 3u);
EXPECT_EQ("EFAKLABBCD", gp2.get_string());
}