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authorRich Felker <dalias@aerifal.cx>2011-02-12 00:22:29 -0500
committerRich Felker <dalias@aerifal.cx>2011-02-12 00:22:29 -0500
commit0b44a0315b47dd8eced9f3b7f31580cf14bbfc01 (patch)
tree6eaef0d8a720fa3da580de87b647fff796fe80b3 /src/network/gethostbyaddr_r.c
downloadmusl-0b44a0315b47dd8eced9f3b7f31580cf14bbfc01.tar.gz
initial check-in, version 0.5.0v0.5.0
Diffstat (limited to 'src/network/gethostbyaddr_r.c')
-rw-r--r--src/network/gethostbyaddr_r.c71
1 files changed, 71 insertions, 0 deletions
diff --git a/src/network/gethostbyaddr_r.c b/src/network/gethostbyaddr_r.c
new file mode 100644
index 00000000..cdb1d503
--- /dev/null
+++ b/src/network/gethostbyaddr_r.c
@@ -0,0 +1,71 @@
+#define _GNU_SOURCE
+
+#include <sys/socket.h>
+#include <netdb.h>
+#include <string.h>
+#include <netinet/in.h>
+#include <errno.h>
+#include <inttypes.h>
+
+int gethostbyaddr_r(const void *a, socklen_t l, int af,
+ struct hostent *h, char *buf, size_t buflen,
+ struct hostent **res, int *err)
+{
+ union {
+ struct sockaddr_in sin;
+ struct sockaddr_in6 sin6;
+ } sa = { .sin.sin_family = af };
+ socklen_t sl = af==AF_INET6 ? sizeof sa.sin6 : sizeof sa.sin;
+ int i;
+
+ /* Load address argument into sockaddr structure */
+ if (af==AF_INET6 && l==16) memcpy(&sa.sin6.sin6_addr, a, 16);
+ else if (af==AF_INET && l==4) memcpy(&sa.sin.sin_addr, a, 4);
+ else {
+ *err = NO_RECOVERY;
+ return -1;
+ }
+
+ /* Align buffer and check for space for pointers and ip address */
+ i = (uintptr_t)buf & sizeof(char *)-1;
+ if (!i) i = sizeof(char *);
+ if (buflen <= 5*sizeof(char *)-i + l) {
+ errno = ERANGE;
+ return -1;
+ }
+ buf += sizeof(char *)-i;
+ buflen -= 5*sizeof(char *)-i + l;
+
+ h->h_addr_list = (void *)buf;
+ buf += 2*sizeof(char *);
+ h->h_aliases = (void *)buf;
+ buf += 2*sizeof(char *);
+
+ h->h_addr_list[0] = buf;
+ memcpy(h->h_addr_list[0], a, l);
+ buf += l;
+ h->h_addr_list[1] = 0;
+ h->h_aliases[0] = buf;
+ h->h_aliases[1] = 0;
+
+ switch (getnameinfo((void *)&sa, sl, buf, buflen, 0, 0, 0)) {
+ case EAI_AGAIN:
+ *err = TRY_AGAIN;
+ return -1;
+ case EAI_OVERFLOW:
+ errno = ERANGE;
+ default:
+ case EAI_MEMORY:
+ case EAI_SYSTEM:
+ case EAI_FAIL:
+ *err = NO_RECOVERY;
+ return -1;
+ case 0:
+ break;
+ }
+
+ h->h_addrtype = af;
+ h->h_name = h->h_aliases[0];
+ *res = h;
+ return 0;
+}