/* Copyright (c) 2002-2018 Dovecot authors, see the included COPYING file */
/* @UNSAFE: whole file */
#include "lib.h"
#include "ioloop.h"
#include "istream-file-private.h"
#include "net.h"
#include <time.h>
#include <unistd.h>
#include <fcntl.h>
#include <sys/stat.h>
void i_stream_file_close(struct iostream_private *stream,
bool close_parent ATTR_UNUSED)
{
struct file_istream *fstream = (struct file_istream *)stream;
struct istream_private *_stream = (struct istream_private *)stream;
if (fstream->autoclose_fd && _stream->fd != -1) {
if (close(_stream->fd) < 0) {
i_error("file_istream.close(%s) failed: %m",
i_stream_get_name(&_stream->istream));
}
}
_stream->fd = -1;
}
static int i_stream_file_open(struct istream_private *stream)
{
const char *path = i_stream_get_name(&stream->istream);
stream->fd = open(path, O_RDONLY);
if (stream->fd == -1) {
io_stream_set_error(&stream->iostream,
"open(%s) failed: %m", path);
stream->istream.stream_errno = errno;
return -1;
}
return 0;
}
ssize_t i_stream_file_read(struct istream_private *stream)
{
struct file_istream *fstream = (struct file_istream *) stream;
uoff_t offset;
size_t size;
ssize_t ret;
if (!i_stream_try_alloc(stream, 1, &size))
return -2;
if (stream->fd == -1) {
if (i_stream_file_open(stream) < 0)
return -1;
i_assert(stream->fd != -1);
}
offset = stream->istream.v_offset + (stream->pos - stream->skip);
if (fstream->file) {
ret = pread(stream->fd, stream->w_buffer + stream->pos,
size, offset);
} else if (fstream->seen_eof) {
/* don't try to read() again. EOF from keyboard (^D)
requires this to work right. */
ret = 0;
} else {
ret = read(stream->fd, stream->w_buffer + stream->pos,
size);
}
if (ret == 0) {
/* EOF */
stream->istream.eof = TRUE;
fstream->seen_eof = TRUE;
return -1;
}
if (unlikely(ret < 0)) {
if ((errno == EINTR || errno == EAGAIN) &&
!stream->istream.blocking) {
ret = 0;
} else {
i_assert(errno != 0);
/* if we get EBADF for a valid fd, it means something's
really wrong and we'd better just crash. */
i_assert(errno != EBADF);
if (fstream->file) {
io_stream_set_error(&stream->iostream,
"pread(size=%"PRIuSIZE_T
" offset=%"PRIuUOFF_T") failed: %m",
size, offset);
} else {
io_stream_set_error(&stream->iostream,
"read(size=%"PRIuSIZE_T") failed: %m",
size);
}
stream->istream.stream_errno = errno;
return -1;
}
}
if (ret > 0 && fstream->skip_left > 0) {
i_assert(!fstream->file);
i_assert(stream->skip == stream->pos);
if (fstream->skip_left >= (size_t)ret) {
fstream->skip_left -= ret;
ret = 0;
} else {
ret -= fstream->skip_left;
stream->pos += fstream->skip_left;
stream->skip += fstream->skip_left;
fstream->skip_left = 0;
}
}
stream->pos += ret;
i_assert(ret != 0 || !fstream->file);
i_assert(ret != -1);
return ret;
}
static void i_stream_file_seek(struct istream_private *stream, uoff_t v_offset,
bool mark ATTR_UNUSED)
{
struct file_istream *fstream = (struct file_istream *) stream;
if (!stream->istream.seekable) {
if (v_offset < stream->istream.v_offset)
i_panic("stream doesn't support seeking backwards");
fstream->skip_left += v_offset - stream->istream.v_offset;
}
stream->istream.v_offset = v_offset;
stream->skip = stream->pos = 0;
fstream->seen_eof = FALSE;
}
static void i_stream_file_sync(struct istream_private *stream)
{
if (!stream->istream.seekable) {
/* can't do anything or data would be lost */
return;
}
stream->skip = stream->pos = 0;
stream->istream.eof = FALSE;
}
static int
i_stream_file_stat(struct istream_private *stream, bool exact ATTR_UNUSED)
{
struct file_istream *fstream = (struct file_istream *) stream;
const char *name = i_stream_get_name(&stream->istream);
if (!fstream->file) {
/* return defaults */
} else if (stream->fd != -1) {
if (fstat(stream->fd, &stream->statbuf) < 0) {
stream->istream.stream_errno = errno;
io_stream_set_error(&stream->iostream,
"file_istream.fstat(%s) failed: %m", name);
i_error("%s", i_stream_get_error(&stream->istream));
return -1;
}
} else {
if (stat(name, &stream->statbuf) < 0) {
stream->istream.stream_errno = errno;
io_stream_set_error(&stream->iostream,
"file_istream.stat(%s) failed: %m", name);
i_error("%s", i_stream_get_error(&stream->istream));
return -1;
}
}
return 0;
}
struct istream *
i_stream_create_file_common(struct file_istream *fstream,
int fd, const char *path,
size_t max_buffer_size, bool autoclose_fd)
{
struct istream *input;
struct stat st;
bool is_file;
int flags;
fstream->autoclose_fd = autoclose_fd;
fstream->istream.iostream.close = i_stream_file_close;
fstream->istream.max_buffer_size = max_buffer_size;
fstream->istream.read = i_stream_file_read;
fstream->istream.seek = i_stream_file_seek;
fstream->istream.sync = i_stream_file_sync;
fstream->istream.stat = i_stream_file_stat;
/* if it's a file, set the flags properly */
if (fd == -1) {
/* only the path is known for now - the fd is opened later */
is_file = TRUE;
} else if (fstat(fd, &st) < 0)
is_file = FALSE;
else if (S_ISREG(st.st_mode))
is_file = TRUE;
else if (!S_ISDIR(st.st_mode))
is_file = FALSE;
else {
/* we're trying to open a directory.
we're not designed for it. */
io_stream_set_error(&fstream->istream.iostream,
"%s is a directory, can't read it as file",
path != NULL ? path : t_strdup_printf("<fd %d>", fd));
fstream->istream.istream.stream_errno = EISDIR;
is_file = FALSE;
}
if (is_file) {
fstream->file = TRUE;
fstream->istream.istream.blocking = TRUE;
fstream->istream.istream.seekable = TRUE;
} else if ((flags = fcntl(fd, F_GETFL, 0)) < 0) {
/* shouldn't happen */
fstream->istream.istream.stream_errno = errno;
io_stream_set_error(&fstream->istream.iostream,
"fcntl(%d, F_GETFL) failed: %m", fd);
} else if ((flags & O_NONBLOCK) == 0) {
/* blocking socket/fifo */
fstream->istream.istream.blocking = TRUE;
}
fstream->istream.istream.readable_fd = TRUE;
input = i_stream_create(&fstream->istream, NULL, fd, 0);
i_stream_set_name(input, is_file ? "(file)" : "(fd)");
return input;
}
struct istream *i_stream_create_fd(int fd, size_t max_buffer_size)
{
struct file_istream *fstream;
i_assert(fd != -1);
fstream = i_new(struct file_istream, 1);
return i_stream_create_file_common(fstream, fd, NULL,
max_buffer_size, FALSE);
}
struct istream *i_stream_create_fd_autoclose(int *fd, size_t max_buffer_size)
{
struct istream *input;
struct file_istream *fstream;
i_assert(*fd != -1);
fstream = i_new(struct file_istream, 1);
input = i_stream_create_file_common(fstream, *fd, NULL,
max_buffer_size, TRUE);
*fd = -1;
return input;
}
struct istream *i_stream_create_file(const char *path, size_t max_buffer_size)
{
struct file_istream *fstream;
struct istream *input;
fstream = i_new(struct file_istream, 1);
input = i_stream_create_file_common(fstream, -1, path,
max_buffer_size, TRUE);
i_stream_set_name(input, path);
return input;
}