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#include <euler/stream.hpp>
#include <cstring>
namespace euler {
stream::~stream() {}
void file_stream::write_buffer() {
if (__euler_write_to_stream(handle, buffer_size, buffer)
!= __EULER_SR_SUCCESS)
good = false;//TODO: more precise error reporting
else
buffer_dirty = false;
}
file_stream::file_stream(
__euler_stream_handle handle, bool is_readable, bool is_writable,
bool clear, bool seek_to_end)
: handle(handle), is_readable(is_readable), is_writable(is_writable),
buffer(0), good(true) {
if (clear) {
if (__euler_set_stream_length(handle, 0) != __EULER_SR_SUCCESS) {
good = false;
return;
}
length = 0;
}
else if (__euler_get_stream_length(handle, length) != __EULER_SR_SUCCESS) {
good = false;
return;
}
if (seek_to_end) {
if (__euler_seek_stream(handle, __EULER_SF_END, 0)
!= __EULER_SR_SUCCESS) {
good = false;
return;
}
offset = length;
}
else
offset = 0;
}
file_stream::~file_stream() {
if (buffer) {
if (buffer_dirty)
write_buffer();
delete[] buffer;
}
__euler_close_stream(handle);
}
bool file_stream::try_read(void *into, uint64_t bytes) {
if (bytes == 0)
return true;
if (offset + bytes > length)
return false;
if (buffer) {
uint64_t start = offset > buffer_offset ? offset : buffer_offset;
uint64_t end = offset + bytes < buffer_offset + buffer_size
? offset + bytes : buffer_offset + buffer_size;
if (end > start) {
uint64_t real_end = offset + bytes;
std::memcpy(
(uint8_t *)into + start - offset, buffer + start - buffer_offset,
end - start);
if (start != offset)
if (!try_read(into, start - offset))
return false;
if (end != real_end) {
if (!try_seek(__EULER_SF_BEGINNING, end))
return false;
if (!try_read((uint8_t *)into + end, real_end - end))
return false;
}
else if (offset != real_end)
if (!try_seek(__EULER_SF_BEGINNING, real_end))
return false;
return true;
}
}
if (buffer_dirty) {
write_buffer();
if (!good)
return false;
}
//1024 is arbitrary
buffer_size = length - offset < 1024 ? length - offset : 1024;
if (buffer != 0)
delete[] buffer;
buffer = new uint8_t[buffer_size];
buffer_dirty = false;
buffer_offset = offset;
if (__euler_read_from_stream(handle, buffer_size, buffer)
!= __EULER_SR_SUCCESS) {
delete[] buffer;
buffer = 0;
return false;
}
uint64_t read_this_buffer = buffer_size < bytes ? buffer_size : bytes;
std::memcpy(into, buffer, read_this_buffer);
offset += read_this_buffer;
if (read_this_buffer == bytes)
return true;
return try_read(
(uint8_t *)into + read_this_buffer, bytes - read_this_buffer);
}
bool file_stream::try_seek(__euler_seek_from from, int64_t offset) {
if (__euler_seek_stream(handle, from, offset) != __EULER_SR_SUCCESS)
return false;
switch (from) {
case __EULER_SF_BEGINNING:
this->offset = offset;
return true;
case __EULER_SF_END:
this->offset = length + offset;
return true;
case __EULER_SF_CURRENT_POSITION:
this->offset += offset;
return true;
default:
return false;
}
}
}
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