X-Git-Url: http://nsz.repo.hu/git/?p=musl;a=blobdiff_plain;f=src%2Fnetwork%2F__dns.c;h=372a58710fb03129a9b35048c8c8a96d306d0f8b;hp=b3c876f36b921e53de927c119725efed9a33c48b;hb=b6f99412019219eda032823030846bc4c90b7cbc;hpb=43ee4df3384853a9c53f4f45b31d190ff9b0d7f0

diff --git a/src/network/__dns.c b/src/network/__dns.c
index b3c876f3..372a5871 100644
--- a/src/network/__dns.c
+++ b/src/network/__dns.c
@@ -5,8 +5,7 @@
 #include <limits.h>
 #include <string.h>
 #include <sys/socket.h>
-#include <sys/select.h>
-#include <sys/time.h>
+#include <poll.h>
 #include <netinet/in.h>
 #include <time.h>
 #include <ctype.h>
@@ -16,16 +15,21 @@
 #include "stdio_impl.h"
 
 #define TIMEOUT 5
-#define RETRY 1
+#define RETRY 1000
 #define PACKET_MAX 512
 #define PTR_MAX (64 + sizeof ".in-addr.arpa")
 
+static void cleanup(void *p)
+{
+	close((intptr_t)p);
+}
+
 int __dns_doqueries(unsigned char *dest, const char *name, int *rr, int rrcnt)
 {
 	time_t t0 = time(0);
 	int fd;
 	FILE *f, _f;
-	unsigned char _buf[64];
+	unsigned char _buf[256];
 	char line[64], *s, *z;
 	union {
 		struct sockaddr_in sin;
@@ -40,11 +44,13 @@ int __dns_doqueries(unsigned char *dest, const char *name, int *rr, int rrcnt)
 	int got = 0, failed = 0;
 	int errcode = EAI_AGAIN;
 	int i, j;
-	struct timeval tv;
-	fd_set fds;
+	struct timespec ts;
+	struct pollfd pfd;
 	int id;
 	int cs;
 
+	pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, &cs);
+
 	/* Construct query template - RR and ID will be filled later */
 	if (strlen(name)-1 >= 254U) return EAI_NONAME;
 	q[2] = q[5] = 1;
@@ -58,8 +64,8 @@ int __dns_doqueries(unsigned char *dest, const char *name, int *rr, int rrcnt)
 	ql = i+4;
 
 	/* Make a reasonably unpredictable id */
-	gettimeofday(&tv, 0);
-	id = tv.tv_usec + tv.tv_usec/256 & 0xffff;
+	clock_gettime(CLOCK_REALTIME, &ts);
+	id = ts.tv_nsec + ts.tv_nsec/65536UL & 0xffff;
 
 	/* Get nameservers from resolv.conf, fallback to localhost */
 	f = __fopen_rb_ca("/etc/resolv.conf", &_f, _buf, sizeof _buf);
@@ -76,23 +82,27 @@ int __dns_doqueries(unsigned char *dest, const char *name, int *rr, int rrcnt)
 	}
 	if (f) __fclose_ca(f);
 	if (!nns) {
-		ns[0].sin.sin_family = AF_INET;
+		ns[0].sin.sin_family = family = AF_INET;
 		ns[0].sin.sin_port = htons(53);
+		ns[0].sin.sin_addr.s_addr = htonl(0x7f000001);
 		nns=1;
 		sl = sizeof sa.sin;
 	}
 
-	pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, &cs);
-
 	/* Get local address and open/bind a socket */
 	sa.sin.sin_family = family;
-	fd = socket(family, SOCK_DGRAM, 0);
+	fd = socket(family, SOCK_DGRAM|SOCK_CLOEXEC|SOCK_NONBLOCK, 0);
+
+	pthread_cleanup_push(cleanup, (void *)(intptr_t)fd);
+	pthread_setcancelstate(cs, 0);
+
 	if (bind(fd, (void *)&sa, sl) < 0) {
 		errcode = EAI_SYSTEM;
 		goto out;
 	}
-	/* Nonblocking to work around Linux UDP select bug */
-	fcntl(fd, F_SETFL, fcntl(fd, F_GETFL, 0) | O_NONBLOCK);
+
+	pfd.fd = fd;
+	pfd.events = POLLIN;
 
 	/* Loop until we timeout; break early on success */
 	for (; time(0)-t0 < TIMEOUT; ) {
@@ -106,11 +116,7 @@ int __dns_doqueries(unsigned char *dest, const char *name, int *rr, int rrcnt)
 		}
 
 		/* Wait for a response, or until time to retry */
-		FD_ZERO(&fds);
-		FD_SET(fd, &fds);
-		tv.tv_sec = RETRY;
-		tv.tv_usec = 0;
-		if (select(fd+1, &fds, 0, 0, &tv) <= 0) continue;
+		if (poll(&pfd, 1, RETRY) <= 0) continue;
 
 		/* Process any and all replies */
 		while (got+failed < rrcnt && (rlen = recvfrom(fd, r, 512, 0,
@@ -145,8 +151,7 @@ int __dns_doqueries(unsigned char *dest, const char *name, int *rr, int rrcnt)
 		if (got+failed == rrcnt) break;
 	}
 out:
-	close(fd);
-	pthread_setcancelstate(cs, 0);
+	pthread_cleanup_pop(1);
 
 	/* Return the number of results, or an error code if none */
 	if (got) return got;