transmission/libtransmission/file.cc

125 lines
2.8 KiB
C++

/*
* This file Copyright (C) 2013-2014 Mnemosyne LLC
*
* It may be used under the GNU GPL versions 2 or 3
* or any future license endorsed by Mnemosyne LLC.
*
*/
#include <algorithm>
#include <cstring> /* strlen() */
#include "transmission.h"
#include "error.h"
#include "file.h"
#include "tr-assert.h"
#include "utils.h"
bool tr_sys_file_read_line(tr_sys_file_t handle, char* buffer, size_t buffer_size, tr_error** error)
{
TR_ASSERT(handle != TR_BAD_SYS_FILE);
TR_ASSERT(buffer != nullptr);
TR_ASSERT(buffer_size > 0);
bool ret = false;
size_t offset = 0;
uint64_t bytes_read;
while (buffer_size > 0)
{
size_t const bytes_needed = std::min(buffer_size, size_t{ 1024 });
ret = tr_sys_file_read(handle, buffer + offset, bytes_needed, &bytes_read, error);
if (!ret || (offset == 0 && bytes_read == 0))
{
ret = false;
break;
}
TR_ASSERT(bytes_read <= bytes_needed);
TR_ASSERT(bytes_read <= buffer_size);
int64_t delta = 0;
for (size_t i = 0; i < bytes_read; ++i)
{
if (buffer[offset] == '\n')
{
delta = i - (int64_t)bytes_read + 1;
break;
}
++offset;
--buffer_size;
}
if (delta != 0 || buffer_size == 0 || bytes_read == 0)
{
if (delta != 0)
{
ret = tr_sys_file_seek(handle, delta, TR_SEEK_CUR, nullptr, error);
if (!ret)
{
break;
}
}
if (offset > 0 && buffer[offset - 1] == '\r')
{
buffer[offset - 1] = '\0';
}
else
{
buffer[offset] = '\0';
}
break;
}
}
return ret;
}
bool tr_sys_file_write_line(tr_sys_file_t handle, char const* buffer, tr_error** error)
{
TR_ASSERT(handle != TR_BAD_SYS_FILE);
TR_ASSERT(buffer != nullptr);
bool ret = tr_sys_file_write(handle, buffer, strlen(buffer), nullptr, error);
if (ret)
{
ret = tr_sys_file_write(handle, TR_NATIVE_EOL_STR, TR_NATIVE_EOL_STR_SIZE, nullptr, error);
}
return ret;
}
bool tr_sys_file_write_fmt(tr_sys_file_t handle, char const* format, tr_error** error, ...)
{
TR_ASSERT(handle != TR_BAD_SYS_FILE);
TR_ASSERT(format != nullptr);
bool ret = false;
char* buffer;
va_list args;
va_start(args, error);
buffer = tr_strdup_vprintf(format, args);
va_end(args);
if (buffer != nullptr)
{
ret = tr_sys_file_write(handle, buffer, strlen(buffer), nullptr, error);
tr_free(buffer);
}
else
{
tr_error_set_literal(error, 0, "Unable to format message.");
}
return ret;
}