xbps/lib/download.c

391 lines
10 KiB
C

/*-
* Copyright (c) 2009-2013 Juan Romero Pardines
* Copyright (c) 2000-2004 Dag-Erling Coïdan Smørgrav
* 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
* in this position and unchanged.
* 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.
* 3. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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.
*
* From FreeBSD fetch(8):
* $FreeBSD: src/usr.bin/fetch/fetch.c,v 1.84.2.1 2009/08/03 08:13:06 kensmith Exp $
*/
#include <sys/param.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/time.h>
#include <stdio.h>
#include <stdlib.h>
#define _BSD_SOURCE /* musl has strlcpy if _{BSD,GNU}_SOURCE is defined */
#include <string.h>
#undef _BSD_SOURCE
#include <errno.h>
#include <fcntl.h>
#include <sys/wait.h>
#include <libgen.h>
#include "xbps_api_impl.h"
#include "fetch.h"
#include "compat.h"
/**
* @file lib/download.c
* @brief Download routines
* @defgroup download Download functions
*
* XBPS download related functions, frontend for NetBSD's libfetch.
*/
static const char *
print_time(time_t *t)
{
struct tm tm;
static char buf[255];
gmtime_r(t, &tm);
strftime(buf, sizeof(buf), "%d %b %Y %H:%M", &tm);
return buf;
}
void HIDDEN
xbps_fetch_set_cache_connection(int global, int per_host)
{
if (global == 0)
global = XBPS_FETCH_CACHECONN;
if (per_host == 0)
per_host = XBPS_FETCH_CACHECONN_HOST;
fetchConnectionCacheInit(global, per_host);
}
void HIDDEN
xbps_fetch_unset_cache_connection(void)
{
fetchConnectionCacheClose();
}
const char *
xbps_fetch_error_string(void)
{
if (fetchLastErrCode == 0 || fetchLastErrCode == FETCH_OK)
return NULL;
return fetchLastErrString;
}
int
xbps_fetch_file_dest(struct xbps_handle *xhp, const char *uri, const char *filename, const char *flags)
{
struct stat st, st_tmpfile, *stp;
struct url *url = NULL;
struct url_stat url_st;
struct fetchIO *fio = NULL;
struct timespec ts[2];
off_t bytes_dload = 0;
ssize_t bytes_read = 0, bytes_written = 0;
char buf[4096], *tempfile = NULL;
char fetch_flags[8];
int fd = -1, rv = 0;
bool refetch = false, restart = false;
assert(xhp);
assert(uri);
/* Extern vars declared in libfetch */
fetchLastErrCode = 0;
if ((url = fetchParseURL(uri)) == NULL)
return -1;
memset(&fetch_flags, 0, sizeof(fetch_flags));
if (flags != NULL)
strlcpy(fetch_flags, flags, 7);
tempfile = xbps_xasprintf("%s.part", filename);
/*
* Check if we have to resume a transfer.
*/
memset(&st_tmpfile, 0, sizeof(st_tmpfile));
if (stat(tempfile, &st_tmpfile) == 0) {
if (st_tmpfile.st_size > 0)
restart = true;
} else {
if (errno != ENOENT) {
rv = -1;
goto fetch_file_out;
}
}
/*
* Check if we have to refetch a transfer.
*/
memset(&st, 0, sizeof(st));
if (stat(filename, &st) == 0) {
refetch = true;
url->last_modified = st.st_mtime;
strlcat(fetch_flags, "i", sizeof(fetch_flags));
} else {
if (errno != ENOENT) {
rv = -1;
goto fetch_file_out;
}
}
if (refetch && !restart) {
/* fetch the whole file, filename available */
stp = &st;
} else {
/* resume transfer, partial file found */
stp = &st_tmpfile;
url->offset = stp->st_size;
}
/*
* Issue a GET request.
*/
fio = fetchXGet(url, &url_st, fetch_flags);
/* debug stuff */
xbps_dbg_printf(xhp, "st.st_size: %zd\n", (ssize_t)stp->st_size);
xbps_dbg_printf(xhp, "st.st_atime: %s\n", print_time(&stp->st_atime));
xbps_dbg_printf(xhp, "st.st_mtime: %s\n", print_time(&stp->st_mtime));
xbps_dbg_printf(xhp, "url->scheme: %s\n", url->scheme);
xbps_dbg_printf(xhp, "url->host: %s\n", url->host);
xbps_dbg_printf(xhp, "url->port: %d\n", url->port);
xbps_dbg_printf(xhp, "url->doc: %s\n", url->doc);
xbps_dbg_printf(xhp, "url->offset: %zd\n", (ssize_t)url->offset);
xbps_dbg_printf(xhp, "url->length: %zu\n", url->length);
xbps_dbg_printf(xhp, "url->last_modified: %s\n",
print_time(&url->last_modified));
xbps_dbg_printf(xhp, "url_stat.size: %zd\n", (ssize_t)url_st.size);
xbps_dbg_printf(xhp, "url_stat.atime: %s\n", print_time(&url_st.atime));
xbps_dbg_printf(xhp, "url_stat.mtime: %s\n", print_time(&url_st.mtime));
if (fio == NULL) {
if (fetchLastErrCode == FETCH_UNCHANGED) {
/* Last-Modified matched */
goto fetch_file_out;
}
rv = -1;
goto fetch_file_out;
}
if (url_st.size == -1) {
xbps_dbg_printf(xhp, "Remote file size is unknown, resume "
"not possible...\n");
restart = false;
} else if (stp->st_size > url_st.size) {
/*
* Remove local file if bigger than remote, and refetch the
* whole shit again.
*/
xbps_dbg_printf(xhp, "Local file %s is greater than remote, "
"removing local file and refetching...\n", filename);
(void)remove(tempfile);
restart = false;
}
/*
* If restarting, open the file for appending otherwise create it.
*/
if (restart)
fd = open(tempfile, O_WRONLY|O_APPEND|O_CLOEXEC);
else
fd = open(tempfile, O_WRONLY|O_CREAT|O_CLOEXEC|O_TRUNC, 0644);
if (fd == -1) {
rv = -1;
goto fetch_file_out;
}
/*
* Initialize data for the fetch progress function callback
* and let the user know that the transfer is going to start
* immediately.
*/
xbps_set_cb_fetch(xhp, url_st.size, url->offset, url->offset,
filename, true, false, false);
/*
* Start fetching requested file.
*/
while ((bytes_read = fetchIO_read(fio, buf, sizeof(buf))) > 0) {
bytes_written = write(fd, buf, (size_t)bytes_read);
if (bytes_written != bytes_read) {
xbps_dbg_printf(xhp,
"Couldn't write to %s!\n", tempfile);
rv = -1;
goto fetch_file_out;
}
bytes_dload += bytes_read;
/*
* Let the fetch progress callback know that
* we are sucking more bytes from it.
*/
xbps_set_cb_fetch(xhp, url_st.size, url->offset,
url->offset + bytes_dload,
filename, false, true, false);
}
if (bytes_read == -1) {
xbps_dbg_printf(xhp, "IO error while fetching %s: %s\n",
filename, fetchLastErrString);
errno = EIO;
rv = -1;
goto fetch_file_out;
} else if (url_st.size > 0 && ((bytes_dload + url->offset) != url_st.size)) {
xbps_dbg_printf(xhp, "file %s is truncated\n", filename);
errno = EIO;
rv = -1;
goto fetch_file_out;
}
/*
* Let the fetch progress callback know that the file
* has been fetched.
*/
xbps_set_cb_fetch(xhp, url_st.size, url->offset, bytes_dload,
filename, false, false, true);
/*
* Update mtime in local file to match remote file if transfer
* was successful.
*/
ts[0].tv_sec = url_st.atime ? url_st.atime : url_st.mtime;
ts[1].tv_sec = url_st.mtime;
ts[0].tv_nsec = ts[1].tv_nsec = 0;
if (futimens(fd, ts) == -1) {
rv = -1;
goto fetch_file_out;
}
(void)close(fd);
fd = -1;
/* File downloaded successfully, rename to destfile */
if (rename(tempfile, filename) == -1) {
xbps_dbg_printf(xhp, "failed to rename %s to %s: %s",
tempfile, filename, strerror(errno));
rv = -1;
goto fetch_file_out;
}
rv = 1;
fetch_file_out:
if (fio != NULL)
fetchIO_close(fio);
if (fd != -1)
(void)close(fd);
if (url != NULL)
fetchFreeURL(url);
if (tempfile != NULL)
free(tempfile);
return rv;
}
int
xbps_fetch_file(struct xbps_handle *xhp, const char *uri, const char *flags)
{
char *filename;
/*
* Get the filename specified in URI argument.
*/
filename = strrchr(uri, '/') + 1;
if (filename == NULL) {
return -1;
}
return xbps_fetch_file_dest(xhp, uri, filename, flags);
}
int
xbps_fetch_delta(struct xbps_handle *xhp, const char *basefile, const char *uri, const char *filename, const char *flags)
{
const char xdelta[] = "/usr/bin/xdelta3";
char *basehash = NULL, *dname = NULL, *durl = NULL, *tempfile = NULL;
int status, exitcode;
pid_t pid;
int rv = 0;
struct stat dummystat;
if (basefile == NULL ||
stat(basefile, &dummystat) ||
stat(xdelta, &dummystat)) {
goto fetch_delta_fallback;
}
xbps_dbg_printf(xhp, "%s: found. Trying binary diff.\n", xdelta);
basehash = xbps_file_hash(basefile);
assert(basehash);
dname = xbps_xasprintf("%s.%s.vcdiff", basename(uri), basehash);
durl = xbps_xasprintf("%s.%s.vcdiff", uri, basehash);
tempfile = xbps_xasprintf("%s.tmp", filename);
if (xbps_fetch_file_dest(xhp, durl, dname, flags) < 0) {
xbps_dbg_printf(xhp, "error while downloading %s, fallback to full "
"download\n", durl);
goto fetch_delta_fallback;
}
if ((pid = fork()) == 0) {
execl(xdelta, xdelta, "-d", "-f", "-s", basefile, dname, tempfile,
NULL);
exit(127);
} else if (pid < 0) {
xbps_dbg_printf(xhp, "error while forking, fallback to full "
"download\n");
goto fetch_delta_fallback;
}
// wait for termination of background process
waitpid(pid, &status, 0);
exitcode = WEXITSTATUS(status);
unlink(dname);
switch(exitcode) {
case 0: // success
rv = 1;
if (rename(tempfile, filename) == -1) {
xbps_dbg_printf(xhp, "failed to rename %s to %s: %s",
tempfile, filename, strerror(errno));
rv = -1;
}
goto fetch_delta_out;
case 127: // cannot execute binary
xbps_dbg_printf(xhp, "failed to `%s`, fallback to full download\n",
xdelta);
goto fetch_delta_fallback;
default: // other error
xbps_dbg_printf(xhp, "`%s` exited with code %d, fallback to full "
"download\n", xdelta, exitcode);
goto fetch_delta_fallback;
}
fetch_delta_fallback:
rv = xbps_fetch_file_dest(xhp, uri, filename, flags);
fetch_delta_out:
if(tempfile != NULL)
free(tempfile);
if(dname != NULL)
free(dname);
if(durl != NULL)
free(durl);
if(basehash != NULL)
free(basehash);
return rv;
}