curl/lib/download.c

586 строки
20 KiB
C

/*****************************************************************************
* _ _ ____ _
* Project ___| | | | _ \| |
* / __| | | | |_) | |
* | (__| |_| | _ <| |___
* \___|\___/|_| \_\_____|
*
* The contents of this file are subject to the Mozilla Public License
* Version 1.0 (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.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS"
* basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See the
* License for the specific language governing rights and limitations
* under the License.
*
* The Original Code is Curl.
*
* The Initial Developer of the Original Code is Daniel Stenberg.
*
* Portions created by the Initial Developer are Copyright (C) 1998.
* All Rights Reserved.
*
* ------------------------------------------------------------
* Main author:
* - Daniel Stenberg <Daniel.Stenberg@haxx.nu>
*
* http://curl.haxx.nu
*
* $Source$
* $Revision$
* $Date$
* $Author$
* $State$
* $Locker$
*
* ------------------------------------------------------------
****************************************************************************/
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include "setup.h"
#ifdef HAVE_SYS_TYPES_H
#include <sys/types.h>
#endif
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif
#ifdef HAVE_SYS_SELECT_H
#include <sys/select.h>
#endif
#include "urldata.h"
#include <curl/curl.h>
#ifdef __BEOS__
#include <net/socket.h>
#endif
#ifdef WIN32
#if !defined( __GNUC__) || defined(__MINGW32__)
#include <winsock.h>
#endif
#include <time.h> /* for the time_t typedef! */
#if defined(__GNUC__) && defined(TIME_WITH_SYS_TIME)
#include <sys/time.h>
#endif
#endif
#include "progress.h"
#include "speedcheck.h"
#include "sendf.h"
#ifdef USE_ZLIB
#include <zlib.h>
#endif
#define MAX(x,y) ((x)>(y)?(x):(y))
/* --- download and upload a stream from/to a socket --- */
/* Parts of this function was brought to us by the friendly Mark Butler
<butlerm@xmission.com>. */
UrgError
Transfer (struct UrlData *data,
/* READ stuff */
int sockfd, /* socket to read from or -1 */
int size, /* -1 if unknown at this point */
bool getheader, /* TRUE if header parsing is wanted */
long *bytecountp, /* return number of bytes read or NULL */
/* WRITE stuff */
int writesockfd, /* socket to write to, it may very well be
the same we read from. -1 disables */
long *writebytecountp /* return number of bytes written or NULL */
)
{
char *buf = data->buffer;
size_t nread;
int bytecount = 0; /* number of bytes read */
int writebytecount = 0; /* number of bytes written */
long contentlength=0; /* size of incoming data */
struct timeval start = tvnow();
struct timeval now = start;
bool header = TRUE; /* incoming data has HTTP header */
int headerline = 0; /* counts header lines to better track the
first one */
char *hbufp; /* points at *end* of header line */
int hbuflen = 0;
char *str; /* within buf */
char *str_start; /* within buf */
char *end_ptr; /* within buf */
char *p; /* within headerbuff */
bool content_range = FALSE; /* set TRUE if Content-Range: was found */
int offset = 0; /* possible resume offset read from the
Content-Range: header */
int code = 0; /* error code from the 'HTTP/1.? XXX' line */
/* for the low speed checks: */
UrgError urg;
time_t timeofdoc=0;
long bodywrites=0;
char newurl[URL_MAX_LENGTH]; /* buffer for Location: URL */
/* the highest fd we use + 1 */
int maxfd = (sockfd>writesockfd?sockfd:writesockfd)+1;
hbufp = data->headerbuff;
myalarm (0); /* switch off the alarm-style timeout */
now = tvnow();
start = now;
#define KEEP_READ 1
#define KEEP_WRITE 2
pgrsTime(data, TIMER_PRETRANSFER);
if (!getheader) {
header = FALSE;
if(size > 0)
pgrsSetDownloadSize(data, size);
}
{
fd_set readfd;
fd_set writefd;
fd_set rkeepfd;
fd_set wkeepfd;
struct timeval interval;
int keepon=0;
/* timeout every X second
- makes a better progressmeter (i.e even when no data is read, the
meter can be updated and reflect reality)
- allows removal of the alarm() crap
- variable timeout is easier
*/
FD_ZERO (&readfd); /* clear it */
if(sockfd != -1) {
FD_SET (sockfd, &readfd); /* read socket */
keepon |= KEEP_READ;
}
FD_ZERO (&writefd); /* clear it */
if(writesockfd != -1) {
FD_SET (writesockfd, &writefd); /* write socket */
keepon |= KEEP_WRITE;
}
/* get these in backup variables to be able to restore them on each lap in
the select() loop */
rkeepfd = readfd;
wkeepfd = writefd;
while (keepon) {
readfd = rkeepfd; /* set those every lap in the loop */
writefd = wkeepfd;
interval.tv_sec = 1;
interval.tv_usec = 0;
switch (select (maxfd, &readfd, &writefd, NULL, &interval)) {
case -1: /* select() error, stop reading */
keepon = 0; /* no more read or write */
continue;
case 0: /* timeout */
break;
default:
if((keepon & KEEP_READ) && FD_ISSET(sockfd, &readfd)) {
/* read! */
#ifdef USE_SSLEAY
if (data->use_ssl) {
nread = SSL_read (data->ssl, buf, BUFSIZE - 1);
}
else {
#endif
nread = sread (sockfd, buf, BUFSIZE - 1);
#ifdef USE_SSLEAY
}
#endif /* USE_SSLEAY */
/* NULL terminate, allowing string ops to be used */
if (0 < (signed int) nread)
buf[nread] = 0;
/* if we receive 0 or less here, the server closed the connection and
we bail out from this! */
else if (0 >= (signed int) nread) {
keepon &= ~KEEP_READ;
break;
}
str = buf; /* Default buffer to use when we write the
buffer, it may be changed in the flow below
before the actual storing is done. */
/* Since this is a two-state thing, we check if we are parsing
headers at the moment or not. */
if (header) {
/* we are in parse-the-header-mode */
/* header line within buffer loop */
do {
int hbufp_index;
str_start = str; /* str_start is start of line within buf */
end_ptr = strchr (str_start, '\n');
if (!end_ptr) {
/* no more complete header lines within buffer */
/* copy what is remaining into headerbuff */
int str_length = (int)strlen(str);
if (hbuflen + (int)str_length >= data->headersize) {
char *newbuff;
long newsize=MAX((hbuflen+str_length)*3/2,
data->headersize*2);
hbufp_index = hbufp - data->headerbuff;
newbuff = (char *)realloc(data->headerbuff, newsize);
if(!newbuff) {
failf (data, "Failed to alloc memory for big header!");
return URG_READ_ERROR;
}
data->headersize=newsize;
data->headerbuff = newbuff;
hbufp = data->headerbuff + hbufp_index;
}
strcpy (hbufp, str);
hbufp += strlen (str);
hbuflen += strlen (str);
break; /* read more and try again */
}
str = end_ptr + 1; /* move just past new line */
if (hbuflen + (str - str_start) >= data->headersize) {
char *newbuff;
long newsize=MAX((hbuflen+(str-str_start))*3/2,
data->headersize*2);
hbufp_index = hbufp - data->headerbuff;
newbuff = (char *)realloc(data->headerbuff, newsize);
if(!newbuff) {
failf (data, "Failed to alloc memory for big header!");
return URG_READ_ERROR;
}
data->headersize= newsize;
data->headerbuff = newbuff;
hbufp = data->headerbuff + hbufp_index;
}
/* copy to end of line */
strncpy (hbufp, str_start, str - str_start);
hbufp += str - str_start;
hbuflen += str - str_start;
*hbufp = 0;
p = data->headerbuff;
/* we now have a full line that p points to */
if (('\n' == *p) || ('\r' == *p)) {
/* Zero-length line means end of header! */
if (-1 != size) /* if known */
size += bytecount; /* we append the already read size */
if ('\r' == *p)
p++; /* pass the \r byte */
if ('\n' == *p)
p++; /* pass the \n byte */
pgrsSetDownloadSize(data, size);
header = FALSE; /* no more header to parse! */
/* now, only output this if the header AND body are requested:
*/
if ((data->conf & (CONF_HEADER | CONF_NOBODY)) ==
CONF_HEADER) {
if((p - data->headerbuff) !=
data->fwrite (data->headerbuff, 1,
p - data->headerbuff, data->out)) {
failf (data, "Failed writing output");
return URG_WRITE_ERROR;
}
}
if(data->writeheader) {
/* obviously, the header is requested to be written to
this file: */
if((p - data->headerbuff) !=
data->fwrite (data->headerbuff, 1, p - data->headerbuff,
data->writeheader)) {
failf (data, "Failed writing output");
return URG_WRITE_ERROR;
}
}
break; /* exit header line loop */
}
if (!headerline++) {
/* This is the first header, it MUST be the error code line
or else we consiser this to be the body right away! */
if (sscanf (p, " HTTP/1.%*c %3d", &code)) {
/* 404 -> URL not found! */
if (
( ((data->conf & CONF_FOLLOWLOCATION) && (code >= 400))
||
!(data->conf & CONF_FOLLOWLOCATION) && (code >= 300))
&& (data->conf & CONF_FAILONERROR)) {
/* If we have been told to fail hard on HTTP-errors,
here is the check for that: */
/* serious error, go home! */
failf (data, "The requested file was not found");
return URG_HTTP_NOT_FOUND;
}
data->progress.httpcode = code;
}
else {
header = FALSE; /* this is not a header line */
break;
}
}
/* check for Content-Length: header lines to get size */
if (strnequal("Content-Length", p, 14) &&
sscanf (p+14, ": %ld", &contentlength))
size = contentlength;
else if (strnequal("Content-Range", p, 13) &&
sscanf (p+13, ": bytes %d-", &offset)) {
if (data->resume_from == offset) {
/* we asked for a resume and we got it */
content_range = TRUE;
}
}
else if(data->cookies &&
strnequal("Set-Cookie: ", p, 11)) {
cookie_add(data->cookies, TRUE, &p[12]);
}
else if(strnequal("Last-Modified:", p,
strlen("Last-Modified:")) &&
data->timecondition) {
time_t secs=time(NULL);
timeofdoc = get_date(p+strlen("Last-Modified:"), &secs);
}
else if ((code >= 300 && code < 400) &&
(data->conf & CONF_FOLLOWLOCATION) &&
strnequal("Location", p, 8) &&
sscanf (p+8, ": %" URL_MAX_LENGTH_TXT "s", newurl)) {
/* this is the URL that the server advices us to get
instead */
data->newurl = strdup (newurl);
}
if (data->conf & CONF_HEADER) {
if(hbuflen != data->fwrite (p, 1, hbuflen, data->out)) {
failf (data, "Failed writing output");
return URG_WRITE_ERROR;
}
}
if(data->writeheader) {
/* the header is requested to be written to this file */
if(hbuflen != data->fwrite (p, 1, hbuflen,
data->writeheader)) {
failf (data, "Failed writing output");
return URG_WRITE_ERROR;
}
}
/* reset hbufp pointer && hbuflen */
hbufp = data->headerbuff;
hbuflen = 0;
}
while (*str); /* header line within buffer */
/* We might have reached the end of the header part here, but
there might be a non-header part left in the end of the read
buffer. */
if (!header) {
/* the next token and forward is not part of
the header! */
/* we subtract the remaining header size from the buffer */
nread -= (str - buf);
}
} /* end if header mode */
/* This is not an 'else if' since it may be a rest from the header
parsing, where the beginning of the buffer is headers and the end
is non-headers. */
if (str && !header && (nread > 0)) {
if(0 == bodywrites) {
/* These checks are only made the first time we are about to
write a chunk of the body */
if(data->conf&CONF_HTTP) {
/* HTTP-only checks */
if (data->resume_from && !content_range ) {
/* we wanted to resume a download, although the server
doesn't seem to support this */
failf (data, "HTTP server doesn't seem to support byte ranges. Cannot resume.");
return URG_HTTP_RANGE_ERROR;
}
else if (data->newurl) {
/* abort after the headers if "follow Location" is set */
infof (data, "Follow to new URL: %s\n", data->newurl);
return URG_OK;
}
else if(data->timecondition && !data->range) {
/* A time condition has been set AND no ranges have been
requested. This seems to be what chapter 13.3.4 of
RFC 2616 defines to be the correct action for a
HTTP/1.1 client */
if((timeofdoc > 0) && (data->timevalue > 0)) {
switch(data->timecondition) {
case TIMECOND_IFMODSINCE:
default:
if(timeofdoc < data->timevalue) {
infof(data,
"The requested document is not new enough");
return URG_OK;
}
break;
case TIMECOND_IFUNMODSINCE:
if(timeofdoc > data->timevalue) {
infof(data,
"The requested document is not old enough");
return URG_OK;
}
break;
} /* switch */
} /* two valid time strings */
} /* we have a time condition */
} /* this is HTTP */
} /* this is the first time we write a body part */
bodywrites++;
if(data->maxdownload &&
(bytecount + nread > data->maxdownload)) {
nread = data->maxdownload - bytecount;
if(nread < 0 ) /* this should be unusual */
nread = 0;
keepon &= ~KEEP_READ; /* we're done reading */
}
bytecount += nread;
pgrsSetDownloadCounter(data, (double)bytecount);
if (nread != data->fwrite (str, 1, nread, data->out)) {
failf (data, "Failed writing output");
return URG_WRITE_ERROR;
}
} /* if (! header and data to read ) */
} /* if( read from socket ) */
if((keepon & KEEP_WRITE) && FD_ISSET(writesockfd, &writefd)) {
/* write */
char scratch[BUFSIZE * 2];
int i, si;
int bytes_written;
if(data->crlf)
buf = data->buffer; /* put it back on the buffer */
nread = data->fread(buf, 1, BUFSIZE, data->in);
writebytecount += nread;
pgrsSetUploadCounter(data, (double)writebytecount);
if (nread<=0) {
/* done */
keepon &= ~KEEP_WRITE; /* we're done writing */
break;
}
/* convert LF to CRLF if so asked */
if (data->crlf) {
for(i = 0, si = 0; i < (int)nread; i++, si++) {
if (buf[i] == 0x0a) {
scratch[si++] = 0x0d;
scratch[si] = 0x0a;
}
else {
scratch[si] = buf[i];
}
}
nread = si;
buf = scratch; /* point to the new buffer */
}
/* write to socket */
#ifdef USE_SSLEAY
if (data->use_ssl) {
bytes_written = SSL_write(data->ssl, buf, nread);
}
else {
#endif
bytes_written = swrite(writesockfd, buf, nread);
#ifdef USE_SSLEAY
}
#endif /* USE_SSLEAY */
if(nread != bytes_written) {
failf(data, "Failed uploading data");
return URG_WRITE_ERROR;
}
}
break;
}
now = tvnow();
pgrsUpdate(data);
urg = speedcheck (data, now);
if (urg)
return urg;
if (data->timeout && (tvdiff (now, start) > data->timeout)) {
failf (data, "Operation timed out with %d out of %d bytes received",
bytecount, size);
return URG_OPERATION_TIMEOUTED;
}
#ifdef MULTIDOC
if(contentlength && bytecount >= contentlength) {
/* we're done with this download, now stop it */
break;
}
#endif
}
}
if(!(data->conf&CONF_NOBODY) && contentlength &&
(bytecount != contentlength)) {
failf(data, "transfer closed with %d bytes remaining to read",
contentlength-bytecount);
return URG_PARTIAL_FILE;
}
pgrsUpdate(data);
if(bytecountp)
*bytecountp = bytecount; /* read count */
if(writebytecountp)
*writebytecountp = writebytecount; /* write count */
return URG_OK;
}