[ashd.git] / src / accesslog.c

/*
    ashd - A Sane HTTP Daemon
    Copyright (C) 2008  Fredrik Tolf <fredrik@dolda2000.com>

    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/

#include <stdlib.h>
#include <stdio.h>
#include <unistd.h>
#include <string.h>
#include <errno.h>
#include <sys/poll.h>
#include <time.h>
#include <sys/time.h>
#include <signal.h>
#include <fcntl.h>
#include <stdint.h>
#include <sys/stat.h>
#include <sys/socket.h>

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#include <utils.h>
#include <log.h>
#include <req.h>
#include <proc.h>
#include <mt.h>
#include <mtio.h>
#include <bufio.h>

#define DEFFORMAT "%{%Y-%m-%d %H:%M:%S}t %m %u %A \"%G\""

static struct logdata {
    struct hthead *req, *resp;
    struct timeval start, end;
    off_t bytesin, bytesout;
} defdata = {
    .bytesin = -1,
    .bytesout = -1,
};

static int ch, filter;
static char *outname = NULL;
static FILE *out;
static int flush = 1, locklog = 1;
static char *format;
static volatile int reopen = 0;

static void qputs(char *sp, FILE *o)
{
    unsigned char *s = (unsigned char *)sp;
    
    for(; *s; s++) {
	if(*s == '\"') {
	    fputs("\\\"", o);
	} else if(*s == '\\') {
	    fputs("\\\\", o);
	} else if(*s == '\n') {
	    fputs("\\n", o);
	} else if(*s == '\t') {
	    fputs("\\t", o);
	} else if((*s < 32) || (*s >= 128)) {
	    fprintf(o, "\\x%02x", (int)*s);
	} else {
	    fputc(*s, o);
	}
    }
}

static void logitem(struct logdata *data, char o, char *d)
{
    char *h, *p;
    char buf[1024];
    
    switch(o) {
    case '%':
	putc('%', out);
	break;
    case 'h':
	if((h = getheader(data->req, d)) == NULL) {
	    putc('-', out);
	} else {
	    qputs(h, out);
	}
	break;
    case 'u':
	qputs(data->req->url, out);
	break;
    case 'U':
	strncpy(buf, data->req->url, sizeof(buf));
	buf[sizeof(buf) - 1] = 0;
	if((p = strchr(buf, '?')) != NULL)
	    *p = 0;
	qputs(buf, out);
	break;
    case 'm':
	qputs(data->req->method, out);
	break;
    case 'r':
	qputs(data->req->rest, out);
	break;
    case 'v':
	qputs(data->req->ver, out);
	break;
    case 't':
	if(!*d)
	    d = "%a, %d %b %Y %H:%M:%S %z";
	strftime(buf, sizeof(buf), d, localtime(&data->start.tv_sec));
	qputs(buf, out);
	break;
    case 'T':
	if(!*d)
	    d = "%a, %d %b %Y %H:%M:%S %z";
	strftime(buf, sizeof(buf), d, gmtime(&data->start.tv_sec));
	qputs(buf, out);
	break;
    case 's':
	fprintf(out, "%06i", (int)data->start.tv_usec);
	break;
    case 'c':
	if(!data->resp)
	    putc('-', out);
	else
	    fprintf(out, "%i", data->resp->code);
	break;
    case 'i':
	if(data->bytesin < 0)
	    putc('-', out);
	else
	    fprintf(out, "%ji", (intmax_t)data->bytesin);
	break;
    case 'o':
	if(data->bytesout < 0)
	    putc('-', out);
	else
	    fprintf(out, "%ji", (intmax_t)data->bytesout);
	break;
    case 'd':
	if((data->end.tv_sec == 0) && (data->end.tv_usec == 0))
	    fputc('-', out);
	else
	    fprintf(out, "%.6f", (data->end.tv_sec - data->start.tv_sec) + ((data->end.tv_usec - data->start.tv_usec) / 1000000.0));
	break;
    case 'A':
	logitem(data, 'h', "X-Ash-Address");
	break;
    case 'H':
	logitem(data, 'h', "Host");
	break;
    case 'R':
	logitem(data, 'h', "Referer");
	break;
    case 'G':
	logitem(data, 'h', "User-Agent");
	break;
    }
}

static void logreq(struct logdata *data)
{
    char *p, *p2;
    char d[strlen(format)];
    char o;
    
    p = format;
    while(*p) {
	if(*p == '%') {
	    p++;
	    if(*p == '{') {
		p++;
		if((p2 = strchr(p, '}')) == NULL)
		    continue;
		memcpy(d, p, p2 - p);
		d[p2 - p] = 0;
		p = p2 + 1;
	    } else {
		d[0] = 0;
	    }
	    o = *p++;
	    if(o == 0)
		break;
	    logitem(data, o, d);
	} else {
	    fputc(*p++, out);
	}
    }
    fputc('\n', out);
    if(flush)
	fflush(out);
}

static void serve(struct hthead *req, int fd)
{
    struct logdata data;
    
    data = defdata;
    data.req = req;
    gettimeofday(&data.start, NULL);
    if(sendreq(ch, req, fd)) {
	flog(LOG_ERR, "accesslog: could not pass request to child: %s", strerror(errno));
	exit(1);
    }
    logreq(&data);
}

static int passdata(struct bufio *in, struct bufio *out, off_t *passed)
{
    ssize_t read;
    off_t total;
    
    total = 0;
    while(!bioeof(in)) {
	if((read = biocopysome(out, in)) < 0)
	    return(-1);
	total += read;
	if(biorspace(in) && (biofillsome(in) < 0))
	    return(-1);
    }
    if(passed)
	*passed = total;
    return(0);
}

static void filterreq(struct muth *mt, va_list args)
{
    vavar(struct hthead *, req);
    vavar(int, fd);
    int pfds[2];
    struct hthead *resp;
    struct bufio *cl, *hd;
    struct logdata data;
    
    hd = NULL;
    resp = NULL;
    data = defdata;
    data.req = req;
    gettimeofday(&data.start, NULL);
    cl = mtbioopen(fd, 1, 600, "r+", NULL);
    if(socketpair(PF_UNIX, SOCK_STREAM, 0, pfds))
	goto out;
    hd = mtbioopen(pfds[1], 1, 600, "r+", NULL);
    if(sendreq(ch, req, pfds[0])) {
	close(pfds[0]);
	goto out;
    }
    close(pfds[0]);
    
    if(passdata(cl, hd, &data.bytesin))
	goto out;
    if(bioflush(hd))
	goto out;
    shutdown(pfds[1], SHUT_WR);
    if((resp = parseresponseb(hd)) == NULL)
	goto out;
    data.resp = resp;
    writerespb(cl, resp);
    bioprintf(cl, "\r\n");
    if(passdata(hd, cl, &data.bytesout))
	goto out;
    gettimeofday(&data.end, NULL);
    
out:
    logreq(&data);
    
    freehthead(req);
    if(resp != NULL)
	freehthead(resp);
    bioclose(cl);
    if(hd != NULL)
	bioclose(hd);
}

static void sighandler(int sig)
{
    if(sig == SIGHUP) {
	if(filter)
	    exitioloop(2);
	else
	    reopen = 1;
    }
}

static int lockfile(FILE *file)
{
    struct flock ld;
    
    memset(&ld, 0, sizeof(ld));
    ld.l_type = F_WRLCK;
    ld.l_whence = SEEK_SET;
    ld.l_start = 0;
    ld.l_len = 0;
    return(fcntl(fileno(file), F_SETLK, &ld));
}

static void fetchpid(char *filename)
{
    int fd, ret;
    struct flock ld;
    
    if((fd = open(filename, O_WRONLY)) < 0) {
	fprintf(stderr, "accesslog: %s: %s\n", filename, strerror(errno));
	exit(1);
    }
    memset(&ld, 0, sizeof(ld));
    ld.l_type = F_WRLCK;
    ld.l_whence = SEEK_SET;
    ld.l_start = 0;
    ld.l_len = 0;
    ret = fcntl(fd, F_GETLK, &ld);
    close(fd);
    if(ret) {
	fprintf(stderr, "accesslog: %s: %s\n", filename, strerror(errno));
	exit(1);
    }
    if(ld.l_type == F_UNLCK) {
	fprintf(stderr, "accesslog: %s: not locked\n", filename);
	exit(1);
    }
    printf("%i\n", (int)ld.l_pid);
}

static void reopenlog(void)
{
    FILE *new;
    struct stat olds, news;
    
    if(outname == NULL) {
	flog(LOG_WARNING, "accesslog: received SIGHUP but logging to stdout, so ignoring");
	return;
    }
    if(locklog) {
	if(fstat(fileno(out), &olds)) {
	    flog(LOG_ERR, "accesslog: could not stat current logfile(?!): %s", strerror(errno));
	    return;
	}
	if(!stat(outname, &news)) {
	    if((olds.st_dev == news.st_dev) && (olds.st_ino == news.st_ino)) {
		/*
		 * This needs to be ignored, because if the same logfile
		 * is opened and then closed, the lock is lost. To quote
		 * the Linux fcntl(2) manpage: "This is bad." No kidding.
		 *
		 * Technically, there is a race condition here when the
		 * file has been stat'ed but not yet opened, where the old
		 * log file, having been previously renamed, changes name
		 * back to the name accesslog knows and is thus reopened
		 * regardlessly, but I think that might fit under the
		 * idiom "pathological case". It should, at least, not be
		 * a security problem.
		 */
		flog(LOG_INFO, "accesslog: received SIGHUP, but logfile has not changed, so ignoring");
		return;
	    }
	}
    }
    if((new = fopen(outname, "a")) == NULL) {
	flog(LOG_WARNING, "accesslog: could not reopen log file `%s' on SIGHUP: %s", outname, strerror(errno));
	return;
    }
    fcntl(fileno(new), F_SETFD, FD_CLOEXEC);
    if(locklog) {
	if(lockfile(new)) {
	    if((errno == EAGAIN) || (errno == EACCES)) {
		flog(LOG_ERR, "accesslog: logfile is already locked; reverting to current log", strerror(errno));
		fclose(new);
		return;
	    } else {
		flog(LOG_WARNING, "accesslog: could not lock logfile, so no lock will be held: %s", strerror(errno));
	    }
	}
    }
    fclose(out);
    out = new;
}

static void listenloop(struct muth *mt, va_list args)
{
    vavar(int, lfd);
    int fd;
    struct hthead *req;
    
    while(1) {
	block(lfd, EV_READ, 0);
	if((fd = recvreq(lfd, &req)) < 0) {
	    if(errno != 0)
		flog(LOG_ERR, "accesslog: error in recvreq: %s", strerror(errno));
	    exit(1);
	}
	mustart(filterreq, req, fd);
    }
}

static void chwatch(struct muth *mt, va_list args)
{
    vavar(int, cfd);
    
    block(cfd, EV_READ, 0);
    exitioloop(1);
}

static void floop(void)
{
    mustart(listenloop, 0);
    mustart(chwatch, ch);
    while(1) {
	switch(ioloop()) {
	case 0:
	case 1:
	    return;
	case 2:
	    reopenlog();
	    break;
	}
    }
}

static void sloop(void)
{
    int fd, ret;
    struct hthead *req;
    struct pollfd pfd[2];
    
    while(1) {
	if(reopen) {
	    reopenlog();
	    reopen = 0;
	}
	memset(pfd, 0, sizeof(pfd));
	pfd[0].fd = 0;
	pfd[0].events = POLLIN;
	pfd[1].fd = ch;
	pfd[1].events = POLLHUP;
	if((ret = poll(pfd, 2, -1)) < 0) {
	    if(errno != EINTR) {
		flog(LOG_ERR, "accesslog: error in poll: %s", strerror(errno));
		exit(1);
	    }
	}
	if(pfd[0].revents) {
	    if((fd = recvreq(0, &req)) < 0) {
		if(errno == 0)
		    return;
		flog(LOG_ERR, "accesslog: error in recvreq: %s", strerror(errno));
		exit(1);
	    }
	    serve(req, fd);
	    freehthead(req);
	    close(fd);
	}
	if(pfd[1].revents & POLLHUP)
	    return;
    }
}

static void usage(FILE *out)
{
    fprintf(out, "usage: accesslog [-hFaL] [-f FORMAT] [-p PIDFILE] OUTFILE CHILD [ARGS...]\n");
    fprintf(out, "       accesslog -P LOGFILE\n");
}

int main(int argc, char **argv)
{
    int c;
    char *pidfile;
    FILE *pidout;
    
    pidfile = NULL;
    while((c = getopt(argc, argv, "+hFaeLf:p:P:")) >= 0) {
	switch(c) {
	case 'h':
	    usage(stdout);
	    exit(0);
	case 'F':
	    flush = 0;
	    break;
	case 'L':
	    locklog = 0;
	    break;
	case 'e':
	    filter = 1;
	    break;
	case 'f':
	    format = optarg;
	    break;
	case 'P':
	    fetchpid(optarg);
	    exit(0);
	case 'p':
	    pidfile = optarg;
	    break;
	case 'a':
	    format = "%A - - [%{%d/%b/%Y:%H:%M:%S %z}t] \"%m %u %v\" %c %o \"%R\" \"%G\"";
	    break;
	default:
	    usage(stderr);
	    exit(1);
	}
    }
    if(argc - optind < 2) {
	usage(stderr);
	exit(1);
    }
    if(format == NULL)
	format = DEFFORMAT;
    if(!strcmp(argv[optind], "-"))
	outname = NULL;
    else
	outname = argv[optind];
    if(outname == NULL) {
	out = stdout;
	locklog = 0;
    } else {
	if((out = fopen(argv[optind], "a")) == NULL) {
	    flog(LOG_ERR, "accesslog: could not open %s for logging: %s", argv[optind], strerror(errno));
	    exit(1);
	}
	fcntl(fileno(out), F_SETFD, FD_CLOEXEC);
    }
    if(locklog) {
	if(lockfile(out)) {
	    if((errno == EAGAIN) || (errno == EACCES)) {
		flog(LOG_ERR, "accesslog: logfile is already locked", strerror(errno));
		exit(1);
	    } else {
		flog(LOG_WARNING, "accesslog: could not lock logfile: %s", strerror(errno));
	    }
	}
    }
    if((ch = stdmkchild(argv + optind + 1, NULL, NULL)) < 0) {
	flog(LOG_ERR, "accesslog: could not fork child: %s", strerror(errno));
	exit(1);
    }
    signal(SIGHUP, sighandler);
    if(pidfile) {
	if(!strcmp(pidfile, "-")) {
	    if(!outname) {
		flog(LOG_ERR, "accesslog: cannot derive PID file name without an output file");
		exit(1);
	    }
	    pidfile = sprintf2("%s.pid", outname);
	}
	if((pidout = fopen(pidfile, "w")) == NULL) {
	    flog(LOG_ERR, "accesslog: could not open PID file %s for writing: %s", pidfile);
	    exit(1);
	}
	fprintf(pidout, "%i\n", (int)getpid());
	fclose(pidout);
    }
    if(filter)
	floop();
    else
	sloop();
    fclose(out);
    if(pidfile != NULL)
	unlink(pidfile);
    return(0);
}
Commit	Line	Data
048ac115 FT	1	/*
	2	ashd - A Sane HTTP Daemon
	3	Copyright (C) 2008 Fredrik Tolf <fredrik@dolda2000.com>
	4
	5	This program is free software: you can redistribute it and/or modify
	6	it under the terms of the GNU General Public License as published by
	7	the Free Software Foundation, either version 3 of the License, or
	8	(at your option) any later version.
	9
	10	This program is distributed in the hope that it will be useful,
	11	but WITHOUT ANY WARRANTY; without even the implied warranty of
	12	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	13	GNU General Public License for more details.
	14
	15	You should have received a copy of the GNU General Public License
	16	along with this program. If not, see <http://www.gnu.org/licenses/>.
	17	*/
	18
	19	#include <stdlib.h>
	20	#include <stdio.h>
	21	#include <unistd.h>
	22	#include <string.h>
	23	#include <errno.h>
	24	#include <sys/poll.h>
	25	#include <time.h>
	26	#include <sys/time.h>
f99bcc64	27	#include <signal.h>
472abd3c	28	#include <fcntl.h>
5c805444	29	#include <stdint.h>
ca170d77	30	#include <sys/stat.h>
5c805444	31	#include <sys/socket.h>
048ac115 FT	32
	33	#ifdef HAVE_CONFIG_H
	34	#include <config.h>
	35	#endif
	36	#include <utils.h>
	37	#include <log.h>
	38	#include <req.h>
	39	#include <proc.h>
5c805444 FT	40	#include <mt.h>
5c805444 FT	41	#include <mtio.h>
b97cd36b	42	#include <bufio.h>
048ac115 FT	43
	44	#define DEFFORMAT "%{%Y-%m-%d %H:%M:%S}t %m %u %A \"%G\""
	45
5c805444 FT	46	static struct logdata {
	47	struct hthead req, resp;
	48	struct timeval start, end;
	49	off_t bytesin, bytesout;
	50	} defdata = {
	51	.bytesin = -1,
	52	.bytesout = -1,
	53	};
	54
	55	static int ch, filter;
f99bcc64	56	static char *outname = NULL;
048ac115	57	static FILE *out;
ca170d77	58	static int flush = 1, locklog = 1;
048ac115	59	static char *format;
f99bcc64	60	static volatile int reopen = 0;
048ac115	61
39522714	62	static void qputs(char sp, FILE o)
048ac115	63	{
39522714 FT	64	unsigned char s = (unsigned char )sp;
39522714 FT	65
048ac115 FT	66	for(; *s; s++) {
	67	if(*s == '\"') {
	68	fputs("\\\"", o);
	69	} else if(*s == '\\') {
	70	fputs("\\\\", o);
	71	} else if(*s == '\n') {
	72	fputs("\\n", o);
	73	} else if(*s == '\t') {
	74	fputs("\\t", o);
	75	} else if((s < 32) \|\| (s >= 128)) {
39522714	76	fprintf(o, "\\x%02x", (int)*s);
048ac115 FT	77	} else {
	78	fputc(*s, o);
	79	}
	80	}
	81	}
	82
5c805444	83	static void logitem(struct logdata data, char o, char d)
048ac115 FT	84	{
	85	char h, p;
	86	char buf[1024];
048ac115 FT	87
	88	switch(o) {
	89	case '%':
	90	putc('%', out);
	91	break;
	92	case 'h':
5c805444	93	if((h = getheader(data->req, d)) == NULL) {
048ac115 FT	94	putc('-', out);
	95	} else {
	96	qputs(h, out);
	97	}
	98	break;
	99	case 'u':
5c805444	100	qputs(data->req->url, out);
048ac115 FT	101	break;
048ac115 FT	102	case 'U':
5c805444 FT	103	strncpy(buf, data->req->url, sizeof(buf));
5c805444 FT	104	buf[sizeof(buf) - 1] = 0;
048ac115 FT	105	if((p = strchr(buf, '?')) != NULL)
	106	*p = 0;
	107	qputs(buf, out);
	108	break;
	109	case 'm':
5c805444	110	qputs(data->req->method, out);
048ac115 FT	111	break;
048ac115 FT	112	case 'r':
5c805444	113	qputs(data->req->rest, out);
048ac115 FT	114	break;
048ac115 FT	115	case 'v':
5c805444	116	qputs(data->req->ver, out);
048ac115 FT	117	break;
	118	case 't':
	119	if(!*d)
	120	d = "%a, %d %b %Y %H:%M:%S %z";
5c805444	121	strftime(buf, sizeof(buf), d, localtime(&data->start.tv_sec));
048ac115 FT	122	qputs(buf, out);
	123	break;
	124	case 'T':
	125	if(!*d)
	126	d = "%a, %d %b %Y %H:%M:%S %z";
5c805444	127	strftime(buf, sizeof(buf), d, gmtime(&data->start.tv_sec));
048ac115 FT	128	qputs(buf, out);
	129	break;
	130	case 's':
5c805444 FT	131	fprintf(out, "%06i", (int)data->start.tv_usec);
	132	break;
	133	case 'c':
	134	if(!data->resp)
	135	putc('-', out);
	136	else
	137	fprintf(out, "%i", data->resp->code);
	138	break;
	139	case 'i':
	140	if(data->bytesin < 0)
	141	putc('-', out);
	142	else
	143	fprintf(out, "%ji", (intmax_t)data->bytesin);
	144	break;
	145	case 'o':
	146	if(data->bytesout < 0)
	147	putc('-', out);
	148	else
	149	fprintf(out, "%ji", (intmax_t)data->bytesout);
	150	break;
	151	case 'd':
	152	if((data->end.tv_sec == 0) && (data->end.tv_usec == 0))
	153	fputc('-', out);
	154	else
	155	fprintf(out, "%.6f", (data->end.tv_sec - data->start.tv_sec) + ((data->end.tv_usec - data->start.tv_usec) / 1000000.0));
048ac115 FT	156	break;
048ac115 FT	157	case 'A':
5c805444	158	logitem(data, 'h', "X-Ash-Address");
048ac115 FT	159	break;
048ac115 FT	160	case 'H':
5c805444	161	logitem(data, 'h', "Host");
048ac115 FT	162	break;
048ac115 FT	163	case 'R':
5c805444	164	logitem(data, 'h', "Referer");
048ac115 FT	165	break;
048ac115 FT	166	case 'G':
5c805444	167	logitem(data, 'h', "User-Agent");
048ac115 FT	168	break;
	169	}
	170	}
	171
5c805444	172	static void logreq(struct logdata *data)
048ac115 FT	173	{
	174	char p, p2;
	175	char d[strlen(format)];
	176	char o;
	177
	178	p = format;
	179	while(*p) {
	180	if(*p == '%') {
	181	p++;
	182	if(*p == '{') {
	183	p++;
	184	if((p2 = strchr(p, '}')) == NULL)
	185	continue;
	186	memcpy(d, p, p2 - p);
	187	d[p2 - p] = 0;
	188	p = p2 + 1;
	189	} else {
	190	d[0] = 0;
	191	}
	192	o = *p++;
	193	if(o == 0)
	194	break;
5c805444	195	logitem(data, o, d);
048ac115 FT	196	} else {
	197	fputc(*p++, out);
	198	}
	199	}
	200	fputc('\n', out);
	201	if(flush)
	202	fflush(out);
	203	}
	204
	205	static void serve(struct hthead *req, int fd)
	206	{
5c805444 FT	207	struct logdata data;
	208
	209	data = defdata;
	210	data.req = req;
	211	gettimeofday(&data.start, NULL);
048ac115 FT	212	if(sendreq(ch, req, fd)) {
	213	flog(LOG_ERR, "accesslog: could not pass request to child: %s", strerror(errno));
	214	exit(1);
	215	}
5c805444 FT	216	logreq(&data);
	217	}
	218
b97cd36b	219	static int passdata(struct bufio in, struct bufio out, off_t *passed)
5c805444	220	{
b97cd36b	221	ssize_t read;
5c805444	222	off_t total;
5c805444 FT	223
5c805444 FT	224	total = 0;
b97cd36b FT	225	while(!bioeof(in)) {
b97cd36b FT	226	if((read = biocopysome(out, in)) < 0)
5c805444 FT	227	return(-1);
5c805444 FT	228	total += read;
b97cd36b FT	229	if(biorspace(in) && (biofillsome(in) < 0))
b97cd36b FT	230	return(-1);
5c805444 FT	231	}
	232	if(passed)
	233	*passed = total;
	234	return(0);
	235	}
	236
	237	static void filterreq(struct muth *mt, va_list args)
	238	{
	239	vavar(struct hthead *, req);
	240	vavar(int, fd);
	241	int pfds[2];
	242	struct hthead *resp;
b97cd36b	243	struct bufio cl, hd;
5c805444 FT	244	struct logdata data;
	245
	246	hd = NULL;
	247	resp = NULL;
	248	data = defdata;
	249	data.req = req;
	250	gettimeofday(&data.start, NULL);
b97cd36b	251	cl = mtbioopen(fd, 1, 600, "r+", NULL);
5c805444 FT	252	if(socketpair(PF_UNIX, SOCK_STREAM, 0, pfds))
5c805444 FT	253	goto out;
b97cd36b	254	hd = mtbioopen(pfds[1], 1, 600, "r+", NULL);
5c805444 FT	255	if(sendreq(ch, req, pfds[0])) {
	256	close(pfds[0]);
	257	goto out;
	258	}
	259	close(pfds[0]);
	260
	261	if(passdata(cl, hd, &data.bytesin))
	262	goto out;
b97cd36b	263	if(bioflush(hd))
ff28e3a5	264	goto out;
5c805444	265	shutdown(pfds[1], SHUT_WR);
b97cd36b	266	if((resp = parseresponseb(hd)) == NULL)
5c805444 FT	267	goto out;
5c805444 FT	268	data.resp = resp;
b97cd36b FT	269	writerespb(cl, resp);
b97cd36b FT	270	bioprintf(cl, "\r\n");
5c805444 FT	271	if(passdata(hd, cl, &data.bytesout))
	272	goto out;
	273	gettimeofday(&data.end, NULL);
	274
	275	out:
	276	logreq(&data);
	277
	278	freehthead(req);
	279	if(resp != NULL)
	280	freehthead(resp);
b97cd36b	281	bioclose(cl);
5c805444	282	if(hd != NULL)
b97cd36b	283	bioclose(hd);
048ac115 FT	284	}
048ac115 FT	285
f99bcc64 FT	286	static void sighandler(int sig)
f99bcc64 FT	287	{
5c805444 FT	288	if(sig == SIGHUP) {
	289	if(filter)
	290	exitioloop(2);
	291	else
	292	reopen = 1;
	293	}
f99bcc64 FT	294	}
f99bcc64 FT	295
ca170d77 FT	296	static int lockfile(FILE *file)
	297	{
	298	struct flock ld;
	299
	300	memset(&ld, 0, sizeof(ld));
	301	ld.l_type = F_WRLCK;
	302	ld.l_whence = SEEK_SET;
	303	ld.l_start = 0;
	304	ld.l_len = 0;
	305	return(fcntl(fileno(file), F_SETLK, &ld));
	306	}
	307
	308	static void fetchpid(char *filename)
	309	{
	310	int fd, ret;
	311	struct flock ld;
	312
	313	if((fd = open(filename, O_WRONLY)) < 0) {
	314	fprintf(stderr, "accesslog: %s: %s\n", filename, strerror(errno));
	315	exit(1);
	316	}
	317	memset(&ld, 0, sizeof(ld));
	318	ld.l_type = F_WRLCK;
	319	ld.l_whence = SEEK_SET;
	320	ld.l_start = 0;
	321	ld.l_len = 0;
	322	ret = fcntl(fd, F_GETLK, &ld);
	323	close(fd);
	324	if(ret) {
	325	fprintf(stderr, "accesslog: %s: %s\n", filename, strerror(errno));
	326	exit(1);
	327	}
	328	if(ld.l_type == F_UNLCK) {
	329	fprintf(stderr, "accesslog: %s: not locked\n", filename);
	330	exit(1);
	331	}
	332	printf("%i\n", (int)ld.l_pid);
	333	}
	334
f99bcc64 FT	335	static void reopenlog(void)
	336	{
	337	FILE *new;
ca170d77	338	struct stat olds, news;
f99bcc64 FT	339
	340	if(outname == NULL) {
	341	flog(LOG_WARNING, "accesslog: received SIGHUP but logging to stdout, so ignoring");
	342	return;
	343	}
ca170d77 FT	344	if(locklog) {
	345	if(fstat(fileno(out), &olds)) {
	346	flog(LOG_ERR, "accesslog: could not stat current logfile(?!): %s", strerror(errno));
	347	return;
	348	}
	349	if(!stat(outname, &news)) {
	350	if((olds.st_dev == news.st_dev) && (olds.st_ino == news.st_ino)) {
	351	/*
	352	* This needs to be ignored, because if the same logfile
	353	* is opened and then closed, the lock is lost. To quote
	354	* the Linux fcntl(2) manpage: "This is bad." No kidding.
	355	*
	356	* Technically, there is a race condition here when the
	357	* file has been stat'ed but not yet opened, where the old
	358	* log file, having been previously renamed, changes name
	359	* back to the name accesslog knows and is thus reopened
	360	* regardlessly, but I think that might fit under the
	361	* idiom "pathological case". It should, at least, not be
	362	* a security problem.
	363	*/
	364	flog(LOG_INFO, "accesslog: received SIGHUP, but logfile has not changed, so ignoring");
	365	return;
	366	}
	367	}
	368	}
f99bcc64 FT	369	if((new = fopen(outname, "a")) == NULL) {
	370	flog(LOG_WARNING, "accesslog: could not reopen log file `%s' on SIGHUP: %s", outname, strerror(errno));
	371	return;
	372	}
e09f3227	373	fcntl(fileno(new), F_SETFD, FD_CLOEXEC);
ca170d77 FT	374	if(locklog) {
	375	if(lockfile(new)) {
	376	if((errno == EAGAIN) \|\| (errno == EACCES)) {
	377	flog(LOG_ERR, "accesslog: logfile is already locked; reverting to current log", strerror(errno));
	378	fclose(new);
	379	return;
	380	} else {
	381	flog(LOG_WARNING, "accesslog: could not lock logfile, so no lock will be held: %s", strerror(errno));
	382	}
	383	}
	384	}
f99bcc64 FT	385	fclose(out);
	386	out = new;
	387	}
	388
5c805444 FT	389	static void listenloop(struct muth *mt, va_list args)
	390	{
	391	vavar(int, lfd);
	392	int fd;
	393	struct hthead *req;
	394
	395	while(1) {
	396	block(lfd, EV_READ, 0);
	397	if((fd = recvreq(lfd, &req)) < 0) {
	398	if(errno != 0)
	399	flog(LOG_ERR, "accesslog: error in recvreq: %s", strerror(errno));
	400	exit(1);
	401	}
	402	mustart(filterreq, req, fd);
	403	}
	404	}
	405
	406	static void chwatch(struct muth *mt, va_list args)
	407	{
	408	vavar(int, cfd);
	409
	410	block(cfd, EV_READ, 0);
	411	exitioloop(1);
	412	}
	413
	414	static void floop(void)
	415	{
	416	mustart(listenloop, 0);
	417	mustart(chwatch, ch);
	418	while(1) {
	419	switch(ioloop()) {
	420	case 0:
	421	case 1:
	422	return;
	423	case 2:
	424	reopenlog();
	425	break;
	426	}
	427	}
	428	}
	429
	430	static void sloop(void)
	431	{
	432	int fd, ret;
	433	struct hthead *req;
	434	struct pollfd pfd[2];
	435
	436	while(1) {
	437	if(reopen) {
	438	reopenlog();
	439	reopen = 0;
	440	}
	441	memset(pfd, 0, sizeof(pfd));
	442	pfd[0].fd = 0;
	443	pfd[0].events = POLLIN;
	444	pfd[1].fd = ch;
	445	pfd[1].events = POLLHUP;
	446	if((ret = poll(pfd, 2, -1)) < 0) {
	447	if(errno != EINTR) {
	448	flog(LOG_ERR, "accesslog: error in poll: %s", strerror(errno));
	449	exit(1);
	450	}
	451	}
	452	if(pfd[0].revents) {
453	if((fd = recvreq(0, &req)) < 0) {
454	if(errno == 0)
455	return;
456	flog(LOG_ERR, "accesslog: error in recvreq: %s", strerror(errno));
457	exit(1);
458	}
459	serve(req, fd);
460	freehthead(req);
461	close(fd);
462	}
463	if(pfd[1].revents & POLLHUP)
464	return;
465	}
466	}
467
048ac115 FT	468	static void usage(FILE *out)
048ac115 FT	469	{
ca170d77	470	fprintf(out, "usage: accesslog [-hFaL] [-f FORMAT] [-p PIDFILE] OUTFILE CHILD [ARGS...]\n");
e51483a1	471	fprintf(out, " accesslog -P LOGFILE\n");
048ac115 FT	472	}
	473
	474	int main(int argc, char **argv)
	475	{
5c805444	476	int c;
472abd3c FT	477	char *pidfile;
472abd3c FT	478	FILE *pidout;
048ac115	479
472abd3c	480	pidfile = NULL;
5c805444	481	while((c = getopt(argc, argv, "+hFaeLf:p:P:")) >= 0) {
048ac115 FT	482	switch(c) {
	483	case 'h':
	484	usage(stdout);
	485	exit(0);
048ac115 FT	486	case 'F':
	487	flush = 0;
	488	break;
ca170d77 FT	489	case 'L':
	490	locklog = 0;
	491	break;
5c805444 FT	492	case 'e':
	493	filter = 1;
	494	break;
048ac115 FT	495	case 'f':
	496	format = optarg;
	497	break;
ca170d77 FT	498	case 'P':
	499	fetchpid(optarg);
	500	exit(0);
472abd3c FT	501	case 'p':
	502	pidfile = optarg;
	503	break;
048ac115	504	case 'a':
5c805444	505	format = "%A - - [%{%d/%b/%Y:%H:%M:%S %z}t] \"%m %u %v\" %c %o \"%R\" \"%G\"";
048ac115 FT	506	break;
	507	default:
	508	usage(stderr);
	509	exit(1);
	510	}
	511	}
9701afc5	512	if(argc - optind < 2) {
048ac115 FT	513	usage(stderr);
	514	exit(1);
	515	}
	516	if(format == NULL)
	517	format = DEFFORMAT;
f99bcc64 FT	518	if(!strcmp(argv[optind], "-"))
	519	outname = NULL;
	520	else
	521	outname = argv[optind];
	522	if(outname == NULL) {
9701afc5	523	out = stdout;
e09f3227	524	locklog = 0;
9701afc5 FT	525	} else {
	526	if((out = fopen(argv[optind], "a")) == NULL) {
	527	flog(LOG_ERR, "accesslog: could not open %s for logging: %s", argv[optind], strerror(errno));
048ac115 FT	528	exit(1);
048ac115 FT	529	}
e09f3227	530	fcntl(fileno(out), F_SETFD, FD_CLOEXEC);
048ac115	531	}
ca170d77 FT	532	if(locklog) {
	533	if(lockfile(out)) {
	534	if((errno == EAGAIN) \|\| (errno == EACCES)) {
	535	flog(LOG_ERR, "accesslog: logfile is already locked", strerror(errno));
	536	exit(1);
	537	} else {
	538	flog(LOG_WARNING, "accesslog: could not lock logfile: %s", strerror(errno));
	539	}
	540	}
	541	}
9701afc5	542	if((ch = stdmkchild(argv + optind + 1, NULL, NULL)) < 0) {
e3f12675	543	flog(LOG_ERR, "accesslog: could not fork child: %s", strerror(errno));
048ac115 FT	544	exit(1);
048ac115 FT	545	}
f99bcc64	546	signal(SIGHUP, sighandler);
472abd3c FT	547	if(pidfile) {
	548	if(!strcmp(pidfile, "-")) {
	549	if(!outname) {
	550	flog(LOG_ERR, "accesslog: cannot derive PID file name without an output file");
	551	exit(1);
	552	}
	553	pidfile = sprintf2("%s.pid", outname);
	554	}
	555	if((pidout = fopen(pidfile, "w")) == NULL) {
	556	flog(LOG_ERR, "accesslog: could not open PID file %s for writing: %s", pidfile);
	557	exit(1);
	558	}
	559	fprintf(pidout, "%i\n", (int)getpid());
	560	fclose(pidout);
	561	}
5c805444 FT	562	if(filter)
	563	floop();
	564	else
	565	sloop();
f95bc205	566	fclose(out);
472abd3c FT	567	if(pidfile != NULL)
472abd3c FT	568	unlink(pidfile);
048ac115 FT	569	return(0);
048ac115 FT	570	}