/* Licensed to the Apache Software Foundation (ASF) under one or more * contributor license agreements. See the NOTICE file distributed with * this work for additional information regarding copyright ownership. * The ASF licenses this file to You under the Apache License, Version 2.0 * (the "License"); you may not use this file except in compliance with * the License. You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ #include "apr_arch_file_io.h" 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_seek(apr_file_t *thefile, apr_seek_where_t where, apr_off_t *offset) { apr_off_t rv; thefile->eof_hit = 0; if (thefile->buffered) { int rc = EINVAL; apr_finfo_t finfo; file_lock(thefile); switch (where) { case APR_SET: rc = setptr(thefile, *offset); break; case APR_CUR: rc = setptr(thefile, thefile->filePtr - thefile->dataRead + thefile->bufpos + *offset); break; case APR_END: rc = apr_file_info_get_locked(&finfo, APR_FINFO_SIZE, thefile); if (rc == APR_SUCCESS) rc = setptr(thefile, finfo.size + *offset); break; } *offset = thefile->filePtr - thefile->dataRead + thefile->bufpos; file_unlock(thefile); return rc; } else { rv = lseek(thefile->filedes, *offset, where); if (rv == -1) { *offset = -1; return errno; } else { *offset = rv; 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; } else if (fp->direction == 0) { /* Discard the read buffer, as we are about to reposition * ourselves to the end of file. */ fp->bufpos = 0; 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); }