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authorVladimir Azarov <avm@intermediate-node.net>2024-10-01 15:47:05 +0200
committerVladimir Azarov <avm@intermediate-node.net>2024-10-01 15:47:05 +0200
commit4abab5ad6c8465a7528ccdd5f49367da05f78bbd (patch)
treeebf009bf1376a5a223a915bc27cbbd791a1316bc /src/network/sendmsg.c
Initial version
Diffstat (limited to 'src/network/sendmsg.c')
-rw-r--r--src/network/sendmsg.c32
1 files changed, 32 insertions, 0 deletions
diff --git a/src/network/sendmsg.c b/src/network/sendmsg.c
new file mode 100644
index 0000000..acdfdf2
--- /dev/null
+++ b/src/network/sendmsg.c
@@ -0,0 +1,32 @@
+#include <sys/socket.h>
+#include <limits.h>
+#include <string.h>
+#include <errno.h>
+#include "syscall.h"
+
+ssize_t sendmsg(int fd, const struct msghdr *msg, int flags)
+{
+#if LONG_MAX > INT_MAX
+ struct msghdr h;
+ /* Kernels before 2.6.38 set SCM_MAX_FD to 255, allocate enough
+ * space to support an SCM_RIGHTS ancillary message with 255 fds.
+ * Kernels since 2.6.38 set SCM_MAX_FD to 253. */
+ struct cmsghdr chbuf[CMSG_SPACE(255*sizeof(int))/sizeof(struct cmsghdr)+1], *c;
+ if (msg) {
+ h = *msg;
+ h.__pad1 = h.__pad2 = 0;
+ msg = &h;
+ if (h.msg_controllen) {
+ if (h.msg_controllen > sizeof chbuf) {
+ errno = ENOMEM;
+ return -1;
+ }
+ memcpy(chbuf, h.msg_control, h.msg_controllen);
+ h.msg_control = chbuf;
+ for (c=CMSG_FIRSTHDR(&h); c; c=CMSG_NXTHDR(&h,c))
+ c->__pad1 = 0;
+ }
+ }
+#endif
+ return socketcall_cp(sendmsg, fd, msg, flags, 0, 0, 0);
+}