11539Srgrimes/* Licensed to the Apache Software Foundation (ASF) under one or more
21539Srgrimes * contributor license agreements.  See the NOTICE file distributed with
31539Srgrimes * this work for additional information regarding copyright ownership.
41539Srgrimes * The ASF licenses this file to You under the Apache License, Version 2.0
51539Srgrimes * (the "License"); you may not use this file except in compliance with
61539Srgrimes * the License.  You may obtain a copy of the License at
71539Srgrimes *
81539Srgrimes *     http://www.apache.org/licenses/LICENSE-2.0
91539Srgrimes *
101539Srgrimes * Unless required by applicable law or agreed to in writing, software
111539Srgrimes * distributed under the License is distributed on an "AS IS" BASIS,
121539Srgrimes * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
131539Srgrimes * See the License for the specific language governing permissions and
141539Srgrimes * limitations under the License.
151539Srgrimes */
161539Srgrimes
171539Srgrimes#include "apr_arch_file_io.h"
181539Srgrimes
191539Srgrimesstatic apr_status_t setptr(apr_file_t *thefile, apr_off_t pos )
201539Srgrimes{
211539Srgrimes    apr_off_t newbufpos;
221539Srgrimes    apr_status_t rv;
231539Srgrimes
241539Srgrimes    if (thefile->direction == 1) {
251539Srgrimes        rv = apr_file_flush_locked(thefile);
261539Srgrimes        if (rv) {
271539Srgrimes            return rv;
281539Srgrimes        }
291539Srgrimes        thefile->bufpos = thefile->direction = thefile->dataRead = 0;
301539Srgrimes    }
311539Srgrimes
321539Srgrimes    newbufpos = pos - (thefile->filePtr - thefile->dataRead);
331539Srgrimes    if (newbufpos >= 0 && newbufpos <= thefile->dataRead) {
341539Srgrimes        thefile->bufpos = newbufpos;
351539Srgrimes        rv = APR_SUCCESS;
361539Srgrimes    }
3793032Simp    else {
381539Srgrimes        if (lseek(thefile->filedes, pos, SEEK_SET) != -1) {
391539Srgrimes            thefile->bufpos = thefile->dataRead = 0;
401539Srgrimes            thefile->filePtr = pos;
411539Srgrimes            rv = APR_SUCCESS;
421539Srgrimes        }
431539Srgrimes        else {
441539Srgrimes            rv = errno;
451539Srgrimes        }
461539Srgrimes    }
471539Srgrimes
481539Srgrimes    return rv;
491539Srgrimes}
501539Srgrimes
511539Srgrimes
521539SrgrimesAPR_DECLARE(apr_status_t) apr_file_seek(apr_file_t *thefile, apr_seek_where_t where, apr_off_t *offset)
5314352Sjkh{
541539Srgrimes    apr_off_t rv;
551539Srgrimes
561539Srgrimes    thefile->eof_hit = 0;
571539Srgrimes
581539Srgrimes    if (thefile->buffered) {
591539Srgrimes        int rc = EINVAL;
601539Srgrimes        apr_finfo_t finfo;
611539Srgrimes
621539Srgrimes        file_lock(thefile);
631539Srgrimes
641539Srgrimes        switch (where) {
651539Srgrimes        case APR_SET:
661539Srgrimes            rc = setptr(thefile, *offset);
6793032Simp            break;
6893032Simp
6993032Simp        case APR_CUR:
7093032Simp            rc = setptr(thefile, thefile->filePtr - thefile->dataRead + thefile->bufpos + *offset);
7193032Simp            break;
7293032Simp
73189808Sdas        case APR_END:
7493032Simp            rc = apr_file_info_get_locked(&finfo, APR_FINFO_SIZE, thefile);
75189808Sdas            if (rc == APR_SUCCESS)
7693032Simp                rc = setptr(thefile, finfo.size + *offset);
7793032Simp            break;
7893032Simp        }
79189808Sdas
8093032Simp        *offset = thefile->filePtr - thefile->dataRead + thefile->bufpos;
81189808Sdas
821539Srgrimes        file_unlock(thefile);
831539Srgrimes
841539Srgrimes        return rc;
85    }
86    else {
87        rv = lseek(thefile->filedes, *offset, where);
88        if (rv == -1) {
89            *offset = -1;
90            return errno;
91        }
92        else {
93            *offset = rv;
94            return APR_SUCCESS;
95        }
96    }
97}
98
99apr_status_t apr_file_trunc(apr_file_t *fp, apr_off_t offset)
100{
101    if (fp->buffered) {
102        int rc = 0;
103        file_lock(fp);
104        if (fp->direction == 1 && fp->bufpos != 0) {
105            apr_off_t len = fp->filePtr + fp->bufpos;
106            if (offset < len) {
107                /* New file end fall below our write buffer limit.
108                 * Figure out if and what needs to be flushed.
109                 */
110                apr_off_t off = len - offset;
111                if (off >= 0 && off <= fp->bufpos)
112                    fp->bufpos = fp->bufpos - (size_t)off;
113                else
114                    fp->bufpos = 0;
115            }
116            rc = apr_file_flush_locked(fp);
117            /* Reset buffer positions for write mode */
118            fp->bufpos = fp->direction = fp->dataRead = 0;
119        }
120        file_unlock(fp);
121        if (rc) {
122            return rc;
123        }
124    }
125    if (ftruncate(fp->filedes, offset) == -1) {
126        return errno;
127    }
128    return apr_file_seek(fp, APR_SET, &offset);
129}
130