Commit 92186b70 authored by Natanael Copa's avatar Natanael Copa

abuild: fix fetch lock file on nfs

flock(2) on an NFS mount will on the server side convert the lock to a
POSIX lock (fcntl(F_SETLK)). This means that abuild running on NFS
server and client will create different locks and they will both try
download same file at same time.

We fix this by creating a small abuild-fetch application that will
create a POSIX lock which works with NFS.
parent bed1c80a
......@@ -11,7 +11,7 @@ abuildrepo ?= ~/.cache/abuild
SCRIPTS := abuild abuild-keygen abuild-sign newapkbuild \
abump apkgrel buildlab apkbuild-cpan checkapk \
apkbuild-gem-resolver
USR_BIN_FILES := $(SCRIPTS) abuild-tar abuild-sudo
USR_BIN_FILES := $(SCRIPTS) abuild-tar abuild-sudo abuild-fetch
SAMPLES := sample.APKBUILD sample.initd sample.confd \
sample.pre-install sample.post-install
AUTOTOOLS_TOOLCHAIN_FILES := config.sub
......@@ -47,6 +47,7 @@ LIBS-abuild-tar = $(SSL_LIBS)
CFLAGS-abuild-tar = $(SSL_CFLAGS)
OBJS-abuild-sudo = abuild-sudo.o
OBJS-abuild-fetch = abuild-fetch.o
.SUFFIXES: .sh.in .in
%.sh: %.sh.in
......@@ -73,6 +74,9 @@ abuild-sudo: abuild-sudo.o
abuild-tar: abuild-tar.o
$(LINK)
abuild-fetch: abuild-fetch.o
$(LINK)
abuild-tar.static: abuild-tar.o
$(CC) $(CPPFLAGS) $(CFLAGS) $(CFLAGS-$@) -o $@ -static $(LIBS-$@) $^
......
/* MIT license
Copyright (C) 2015 Natanael Copa <ncopa@alpinelinux.org>
Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
THE SOFTWARE.
*/
#include <sys/wait.h>
#include <err.h>
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
static char *program;
static char lockfile[PATH_MAX] = "";
struct cmdarray {
size_t argc;
char *argv[32];
};
void add_opt(struct cmdarray *cmd, char *opt)
{
cmd->argv[cmd->argc++] = opt;
cmd->argv[cmd->argc] = NULL;
}
int usage(int eval)
{
printf("usage: %s [-d DESTDIR] URL\n", program);
return eval;
}
/* create or wait for an NFS-safe lockfile and fetch url with curl or wget */
int fetch(char *url, const char *destdir)
{
int lockfd, status=0;
pid_t childpid;
char outfile[PATH_MAX], partfile[PATH_MAX];
char *name, *p;
struct flock fl = {
.l_type = F_WRLCK,
.l_whence = SEEK_SET,
.l_start = 1,
.l_len = 0,
};
struct cmdarray curlcmd = {
.argc = 6,
.argv = { "curl", "-k", "-L", "-f", "-o", partfile, NULL }
};
struct cmdarray wgetcmd = {
.argc = 3,
.argv = { "wget", "-O", partfile, NULL }
};
name = strrchr(url, '/');
if (name == NULL)
errx(1, "%s: no '/' in url");
p = strstr(url, "::");
if (p != NULL) {
name = url;
*p = '\0';
url = p + 2;
} else if (strstr(url, "saveas-") == url) {
*name++ = '\0';
url += 7; /* strlen("saveas-") */
} else {
name++;
}
snprintf(outfile, sizeof(outfile), "%s/%s", destdir, name);
snprintf(lockfile, sizeof(lockfile), "%s.lock", outfile);
snprintf(partfile, sizeof(partfile), "%s.part", outfile);
lockfd = open(lockfile, O_WRONLY|O_CREAT, 0660);
if (lockfd < 0)
err(1, lockfile);
if (fcntl(lockfd, F_SETLK, &fl) < 0) {
printf("Waiting for %s ...\n", lockfile);
if (fcntl(lockfd, F_SETLKW, &fl) < 0)
err(1, "fcntl(F_SETLKW)");
}
if (access(outfile, F_OK) == 0)
goto fetch_done;
if (access(partfile, F_OK) == 0) {
printf("Partial download found. Trying to resume.\n");
add_opt(&curlcmd, "-C");
add_opt(&curlcmd, "-");
add_opt(&wgetcmd, "-c");
}
add_opt(&curlcmd, url);
add_opt(&wgetcmd, url);
childpid = fork();
if (childpid < 0 )
err(1, "fork");
if (childpid == 0) {
execvp(curlcmd.argv[0], curlcmd.argv);
printf("Using wget\n");
execvp(wgetcmd.argv[0], wgetcmd.argv);
warn(wgetcmd.argv[0]);
unlink(lockfile);
exit(1);
}
wait(&status);
rename(partfile, outfile);
fetch_done:
unlink(lockfile);
close(lockfd);
lockfile[0] = '\0';
return status;
}
void sighandler(int sig)
{
switch(sig) {
case SIGABRT:
case SIGINT:
case SIGQUIT:
case SIGTERM:
unlink(lockfile);
exit(0);
break;
default:
break;
}
}
int main(int argc, char *argv[])
{
int opt, r=0, i;
char *destdir = "/var/cache/distfiles";
program = argv[0];
while ((opt = getopt(argc, argv, "hd:")) != -1) {
switch (opt) {
case 'h':
return usage(0);
break;
case 'd':
destdir = optarg;
break;
default:
printf("Unkonwn option '%c'\n", opt);
return usage(1);
break;
}
}
argv += optind;
argc -= optind;
if (argc < 1)
return usage(1);
signal(SIGABRT, sighandler);
signal(SIGINT, sighandler);
signal(SIGQUIT, sighandler);
signal(SIGTERM, sighandler);
for (i = 0; i < argc; i++) {
if (fetch(argv[i], destdir))
r++;
}
return r;
}
......@@ -298,79 +298,12 @@ sourcecheck() {
return 0
}
# convert curl options to wget options and call wget instead of curl
wget_fallback() {
local wget_opts= outfile= opt=
while getopts "C:Lko:s" opt; do
case $opt in
'L') ;; # --location. wget does this by default
'f') ;; # --fail. wget does this by default
'C') wget_opts="$wget_opts -c";; # --continue-at
's') wget_opts="$wget_opts -q";; # --silent
'o') wget_opts="$wget_opts -O $OPTARG";; # --output
'k') wget_opts="$wget_opts --no-check-certificate";; #gnu wget
esac
done
shift $(( $OPTIND - 1 ))
wget $wget_opts "$1"
}
uri_fetch() {
local uri="$1"
local d="${uri##*/}" # $(basename $uri)
local opts
[ -n "$quiet" ] && opts="-s"
local lockfile="$SRCDEST/$d".lock
# fix saveas-*://* URIs
case "$uri" in
# remove 'saveas-' from beginning and
# '/filename' from end of URI
saveas-*://*) uri="${uri:7:$(expr ${#uri} - 7 - ${#d} - 1)}";;
*::*)
d=${uri%%::*}
uri=${uri#$d::}
;;
esac
case "$uri" in
https://*) opts="-k";;
esac
mkdir -p "$SRCDEST"
CLEANUP_FILES="$CLEANUP_FILES $lockfile"
(
flock -n -x 9 || msg "Waiting for ${lockfile##*/}..."
flock -x 9
[ -f "$SRCDEST/$d" ] && exit 0 # use exit since its a subshell
if [ -f "$SRCDEST/$d.part" ]; then
msg "Partial download found. Trying to resume"
opts="$opts -C -"
fi
msg "Fetching $uri"
# fallback to wget if curl is missing. useful for bootstrapping
local fetcher=
if ! [ -x "$(which curl)" ]; then
fetcher=wget_fallback
else
fetcher=curl
opts="$opts -L -f -k"
fi
$fetcher $opts -o "$SRCDEST/$d.part" "$uri" \
&& mv "$SRCDEST/$d.part" "$SRCDEST/$d"
) 9>$lockfile
local rc=$?
rm -f "$lockfile"
return $rc
abuild-fetch -d "$SRCDEST" "$uri"
}
is_remote() {
......
Markdown is supported
0% or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment