APR_DECLARE(apr_status_t) apr_file_buffer_set(apr_file_t *file,
char * buffer,
apr_size_t bufsize)
{
apr_status_t rv;
file_lock(file);
if(file->buffered) {
/* Flush the existing buffer */
rv = apr_file_flush_locked(file);
if (rv != APR_SUCCESS) {
file_unlock(file);
return rv;
}
}
file->buffer = buffer;
file->bufsize = bufsize;
file->buffered = 1;
file->bufpos = 0;
file->direction = 0;
file->dataRead = 0;
if (file->bufsize == 0) {
/* Setting the buffer size to zero is equivalent to turning
* buffering off.
*/
file->buffered = 0;
}
file_unlock(file);
return APR_SUCCESS;
}
apr_status_t apr_file_trunc(apr_file_t *fp, apr_off_t offset)
{
if (fp->buffered) {
int rc = 0;
file_lock(fp);
if (fp->direction == 1 && fp->bufpos != 0) {
apr_off_t len = fp->filePtr + fp->bufpos;
if (offset < len) {
/* New file end fall below our write buffer limit.
* Figure out if and what needs to be flushed.
*/
apr_off_t off = len - offset;
if (off >= 0 && off <= fp->bufpos)
fp->bufpos = fp->bufpos - (size_t)off;
else
fp->bufpos = 0;
}
rc = apr_file_flush_locked(fp);
/* Reset buffer positions for write mode */
fp->bufpos = fp->direction = fp->dataRead = 0;
}
file_unlock(fp);
if (rc) {
return rc;
}
}
if (ftruncate(fp->filedes, offset) == -1) {
return errno;
}
return apr_file_seek(fp, APR_SET, &offset);
}
static apr_status_t setptr(apr_file_t *thefile, apr_off_t pos )
{
apr_off_t newbufpos;
apr_status_t rv;
if (thefile->direction == 1) {
rv = apr_file_flush_locked(thefile);
if (rv) {
return rv;
}
thefile->bufpos = thefile->direction = thefile->dataRead = 0;
}
newbufpos = pos - (thefile->filePtr - thefile->dataRead);
if (newbufpos >= 0 && newbufpos <= thefile->dataRead) {
thefile->bufpos = newbufpos;
rv = APR_SUCCESS;
}
else {
if (lseek(thefile->filedes, pos, SEEK_SET) != -1) {
thefile->bufpos = thefile->dataRead = 0;
thefile->filePtr = pos;
rv = APR_SUCCESS;
}
else {
rv = errno;
}
}
return rv;
}
APR_DECLARE(apr_status_t) apr_file_writev(apr_file_t *thefile, const struct iovec *vec,
apr_size_t nvec, apr_size_t *nbytes)
{
#ifdef HAVE_WRITEV
apr_status_t rv;
int bytes;
if (thefile->buffered) {
file_lock(thefile);
rv = apr_file_flush_locked(thefile);
if (rv != APR_SUCCESS) {
file_unlock(thefile);
return rv;
}
if (thefile->direction == 0) {
/* Position file pointer for writing at the offset we are
* logically reading from
*/
apr_int64_t offset = thefile->filePtr - thefile->dataRead +
thefile->bufpos;
if (offset != thefile->filePtr)
lseek(thefile->filedes, offset, SEEK_SET);
thefile->bufpos = thefile->dataRead = 0;
}
file_unlock(thefile);
}
if ((bytes = writev(thefile->filedes, vec, nvec)) < 0) {
*nbytes = 0;
rv = errno;
}
else {
*nbytes = bytes;
rv = APR_SUCCESS;
}
return rv;
#else
/**
* The problem with trying to output the entire iovec is that we cannot
* maintain the behavoir that a real writev would have. If we iterate
* over the iovec one at a time, we loose the atomic properties of
* writev(). The other option is to combine the entire iovec into one
* buffer that we could then send in one call to write(). This is not
* reasonable since we do not know how much data an iovec could contain.
*
* The only reasonable option, that maintains the semantics of a real
* writev(), is to only write the first iovec. Callers of file_writev()
* must deal with partial writes as they normally would. If you want to
* ensure an entire iovec is written, use apr_file_writev_full().
*/
*nbytes = vec[0].iov_len;
return apr_file_write(thefile, vec[0].iov_base, nbytes);
#endif
}
static apr_status_t file_read_buffered(apr_file_t *thefile, void *buf,
apr_size_t *nbytes)
{
apr_ssize_t rv;
char *pos = (char *)buf;
apr_uint64_t blocksize;
apr_uint64_t size = *nbytes;
if (thefile->direction == 1) {
rv = apr_file_flush_locked(thefile);
if (rv) {
return rv;
}
thefile->bufpos = 0;
thefile->direction = 0;
thefile->dataRead = 0;
}
rv = 0;
if (thefile->ungetchar != -1) {
*pos = (char)thefile->ungetchar;
++pos;
--size;
thefile->ungetchar = -1;
}
while (rv == 0 && size > 0) {
if (thefile->bufpos >= thefile->dataRead) {
int bytesread = read(thefile->filedes, thefile->buffer, APR_FILE_BUFSIZE);
if (bytesread == 0) {
thefile->eof_hit = TRUE;
rv = APR_EOF;
break;
}
else if (bytesread == -1) {
rv = errno;
break;
}
thefile->dataRead = bytesread;
thefile->filePtr += thefile->dataRead;
thefile->bufpos = 0;
}
blocksize = size > thefile->dataRead - thefile->bufpos ? thefile->dataRead - thefile->bufpos : size;
memcpy(pos, thefile->buffer + thefile->bufpos, blocksize);
thefile->bufpos += blocksize;
pos += blocksize;
size -= blocksize;
}
*nbytes = pos - (char *)buf;
if (*nbytes) {
rv = 0;
}
return rv;
}
APR_DECLARE(apr_status_t) apr_file_gets(char *str, int len, apr_file_t *thefile)
{
apr_status_t rv = APR_SUCCESS; /* get rid of gcc warning */
apr_size_t nbytes;
const char *str_start = str;
char *final = str + len - 1;
if (len <= 1) {
/* sort of like fgets(), which returns NULL and stores no bytes
*/
return APR_SUCCESS;
}
/* If we have an underlying buffer, we can be *much* more efficient
* and skip over the apr_file_read calls.
*/
if (thefile->buffered) {
file_lock(thefile);
if (thefile->direction == 1) {
rv = apr_file_flush_locked(thefile);
if (rv) {
file_unlock(thefile);
return rv;
}
thefile->direction = 0;
thefile->bufpos = 0;
thefile->dataRead = 0;
}
while (str < final) { /* leave room for trailing '\0' */
/* Force ungetc leftover to call apr_file_read. */
if (thefile->bufpos < thefile->dataRead &&
thefile->ungetchar == -1) {
*str = thefile->buffer[thefile->bufpos++];
}
else {
nbytes = 1;
rv = file_read_buffered(thefile, str, &nbytes);
if (rv != APR_SUCCESS) {
break;
}
}
if (*str == '\n') {
++str;
break;
}
++str;
}
file_unlock(thefile);
}
APR_DECLARE(apr_status_t) apr_file_flush(apr_file_t *thefile)
{
apr_status_t rv = APR_SUCCESS;
if (thefile->buffered) {
file_lock(thefile);
rv = apr_file_flush_locked(thefile);
file_unlock(thefile);
}
/* There isn't anything to do if we aren't buffering the output
* so just return success.
*/
return rv;
}
apr_status_t apr_file_info_get_locked(apr_finfo_t *finfo, apr_int32_t wanted,
apr_file_t *thefile)
{
struct_stat info;
if (thefile->buffered) {
apr_status_t rv = apr_file_flush_locked(thefile);
if (rv != APR_SUCCESS)
return rv;
}
if (fstat(thefile->filedes, &info) == 0) {
finfo->pool = thefile->pool;
finfo->fname = thefile->fname;
fill_out_finfo(finfo, &info, wanted);
return (wanted & ~finfo->valid) ? APR_INCOMPLETE : APR_SUCCESS;
}
else {
return errno;
}
}
APR_DECLARE(apr_status_t) apr_file_write(apr_file_t *thefile, const void *buf, apr_size_t *nbytes)
{
apr_size_t rv;
if (thefile->buffered) {
char *pos = (char *)buf;
int blocksize;
int size = *nbytes;
file_lock(thefile);
if ( thefile->direction == 0 ) {
/* Position file pointer for writing at the offset we are
* logically reading from
*/
apr_int64_t offset = thefile->filePtr - thefile->dataRead + thefile->bufpos;
if (offset != thefile->filePtr)
lseek(thefile->filedes, offset, SEEK_SET);
thefile->bufpos = thefile->dataRead = 0;
thefile->direction = 1;
}
rv = 0;
while (rv == 0 && size > 0) {
if (thefile->bufpos == APR_FILE_BUFSIZE) /* write buffer is full*/
rv = apr_file_flush_locked(thefile);
blocksize = size > APR_FILE_BUFSIZE - thefile->bufpos ?
APR_FILE_BUFSIZE - thefile->bufpos : size;
memcpy(thefile->buffer + thefile->bufpos, pos, blocksize);
thefile->bufpos += blocksize;
pos += blocksize;
size -= blocksize;
}
file_unlock(thefile);
return rv;
}
else {
do {
rv = write(thefile->filedes, buf, *nbytes);
} while (rv == (apr_size_t)-1 && errno == EINTR);
#ifdef USE_WAIT_FOR_IO
if (rv == (apr_size_t)-1 &&
(errno == EAGAIN || errno == EWOULDBLOCK) &&
thefile->timeout != 0) {
apr_status_t arv = apr_wait_for_io_or_timeout(thefile, NULL, 0);
if (arv != APR_SUCCESS) {
*nbytes = 0;
return arv;
}
else {
do {
do {
rv = write(thefile->filedes, buf, *nbytes);
} while (rv == (apr_size_t)-1 && errno == EINTR);
if (rv == (apr_size_t)-1 &&
(errno == EAGAIN || errno == EWOULDBLOCK)) {
*nbytes /= 2; /* yes, we'll loop if kernel lied
* and we can't even write 1 byte
*/
}
else {
break;
}
} while (1);
}
}
#endif
if (rv == (apr_size_t)-1) {
(*nbytes) = 0;
return errno;
}
*nbytes = rv;
return APR_SUCCESS;
}
}
