src/server/safs/service.c

/*
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
 *
 * Copyright 2013 Olaf Wintermann. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 *   1. Redistributions of source code must retain the above copyright
 *      notice, this list of conditions and the following disclaimer.
 *
 *   2. Redistributions in binary form must reproduce the above copyright
 *      notice, this list of conditions and the following disclaimer in the
 *      documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

#include <stdio.h>
#include <sys/file.h>
#include <sys/stat.h>

#include "service.h"
#include "../util/io.h"
#include "../util/pblock.h"
#include "../daemon/protocol.h"

#include <sys/sendfile.h>
#include "../util/strbuf.h"

#include <errno.h>

// TODO: system sendfile Abstraktionen in neue Datei auslagern
/*
ssize_t sys_sendfile(int out_fd, int in_fd, off_t *off, size_t len) {
    
}
*/
#define sys_sendfile sendfile


/*
 * prepares for servicing a file
 *
 * adds content-length header and starts the response
 *
 * return the file descriptor or -1
 */
int prepare_service_file(Session *sn, Request *rq) {
    char *ppath = pblock_findkeyval(pb_key_ppath, rq->vars);

    /* open the file */
    int fd = open(ppath, O_RDONLY);
    if(fd < 0) {
        //perror("prepare_service_file: open");

        int status = 500;
        int en = errno;
        switch(en) {
            case EACCES: {
                status = 403;
                break;
            }
            case ENOENT: {
                status = 404;
                break;
            }
        }
        protocol_status(sn, rq, status, NULL);
        return -1;
    }

    /* get stat */
    struct stat stat;
    if (fstat(fd, &stat) != 0) {
        //perror("prepare_service_file: stat");

        protocol_status(sn, rq, 500, NULL);
        return -1;
    }

    /* add content-length header*/
    char contentLength[32];
    int len = snprintf(contentLength, 32, "%d", stat.st_size);

    pblock_kvinsert(pb_key_content_length, contentLength, len, rq->srvhdrs);

    /* start response */
    protocol_status(sn, rq, 200, NULL);
    http_start_response(sn, rq);

    return fd;
}

int send_file(pblock *pb, Session *sn, Request *rq) {
    int fd = prepare_service_file(sn, rq);
    if(fd < 0) {
        // if an error occurs, prepare_service_file sets the http status code
        // we can just return REQ_ABORTED
        return REQ_ABORTED;
    }

    /* send file*/
    SystemIOStream *io = (SystemIOStream*) sn->csd;

    off_t fileoffset = 0;
    int len = atoi(pblock_findkeyval(pb_key_content_length, rq->srvhdrs));
    sendfile(io->fd, fd, &fileoffset, len);

    close(fd);

    return REQ_PROCEED;
}

int service_hello(pblock *pb, Session *sn, Request *rq) {
    pblock_removekey(pb_key_content_type, rq->srvhdrs);
    pblock_nvinsert("content-type", "text/plain", rq->srvhdrs);
    pblock_nninsert("content-length", 13, rq->srvhdrs);
    protocol_status(sn, rq, 200, NULL);
    http_start_response(sn, rq);
    net_write(sn->csd, "Hello World!\n", 13);
    return REQ_PROCEED;
}

int service_index(pblock *pb, Session *sn, Request *rq) {
    //printf("service_index\n");

    char *ppath = pblock_findkeyval(pb_key_ppath, rq->vars);
    char *uri = pblock_findkeyval(pb_key_uri, rq->reqpb);

    sstr_t r_uri = sstr(uri);

    /* open the file */
    int fd = open(ppath, O_RDONLY);
    if(fd < 0) {
        //perror("service_index: open");

        int status = 500;
        switch(errno) {
            case EACCES: {
                status = 403;
                break;
            }
            case ENOENT: {
                status = 404;
                break;
            }
        }
        protocol_status(sn, rq, status, NULL);
        //printf("REQ_ABORTED\n");
        return REQ_ABORTED;
    }

    DIR *dir = fdopendir(fd);
    if(dir == NULL) {
        protocol_status(sn, rq, 500, NULL);
        //printf("DIR is null\n");
        return REQ_ABORTED;
    }

    sbuf_t *out = sbuf_new(1024); /* output buffer */

    /* write html header  */
    sbuf_puts(out, "<html>\n<head>\n<title>Index of ");
    sbuf_puts(out, uri);
    sbuf_puts(out, "</title>\n</head><body>\n<h1>Index of ");
    sbuf_puts(out, uri);
    sbuf_puts(out, "</h1><hr>\n\n");

    struct dirent *f;
    while((f = readdir(dir)) != NULL) {
        if(strcmp(f->d_name, ".") == 0 || strcmp(f->d_name, "..") == 0) {
            continue;
        }

        sstr_t filename = sstr(f->d_name);

        sbuf_puts(out, "<a href=\"");
        sbuf_append(out, r_uri);
        sbuf_append(out, filename);
        sbuf_puts(out, "\">");
        sbuf_append(out, filename);
        sbuf_puts(out, "</a><br>\n");
    }

    sbuf_puts(out, "\n</body>\n</html>\n");

    /* send stuff to client */
    pblock_removekey(pb_key_content_type, rq->srvhdrs);
    pblock_kvinsert(pb_key_content_type, "text/html", 9, rq->srvhdrs);
    pblock_nninsert("content-length", out->length, rq->srvhdrs);
    protocol_status(sn, rq, 200, NULL);
    http_start_response(sn, rq);

    net_write(sn->csd, out->ptr, out->length);

    /* close */
    closedir(dir);
    sbuf_free(out);

    return REQ_PROCEED;
}

int send_options(pblock *pb, Session *sn, Request *rq) {
    char *allow = "HEAD, GET, PUT, DELETE, TRACE, OPTIONS, MOVE, COPY, "
            "PROPFIND, PROPPATCH, MKCOL, LOCK, UNLOCK, ACL, REPORT";
    char *dav = "1,2,access-control";

    pblock_removekey(pb_key_content_type, rq->srvhdrs);
    pblock_nvinsert("allow", allow, rq->srvhdrs);
    pblock_nvinsert("dav", dav, rq->srvhdrs);
    pblock_nninsert("content-length", 0, rq->srvhdrs);
    protocol_status(sn, rq, 200, NULL);
    http_start_response(sn, rq);

    return REQ_PROCEED;
}