upstream/mercurial-mirror Files · rust/chg/src/sendfds.c

rust: Add type annotation to fix inference on Rust Nightly...

rust: Add type annotation to fix inference on Rust Nightly When compiling with Rust Nightly, the im-rs crate silently makes use of the experimental language feature for trait impl specialization. This apperently changes public its APIs in subtle ways such that type inference of some user code can fail where it succeeds when specialization is disabled. This made Mercurial’s Rust unit tests have compilation errors on Nightly. I have not managed to find the exactl root cause, but I wrote down my findings so far at https://github.com/bodil/im-rs/issues/188 This adds type annotation to make unit tests rely less on type inference and work around the issue. Differential Revision: https://phab.mercurial-scm.org/D10742

Yuya Nishihara - - Load All Authors

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      /*

       * Utility to send fds via Unix domain socket

       *

       * Copyright 2011, 2018 Yuya Nishihara <yuya@tcha.org>

       *

       * This software may be used and distributed according to the terms of the

       * GNU General Public License version 2 or any later version.

       */

      #include <errno.h>

      #include <stdlib.h>

      #include <string.h>

      #include <sys/socket.h>

      #include <sys/types.h>

      #define MAX_FD_LEN 10

      /*

       * Sends the given fds with 1-byte dummy payload.

       *

       * Returns the number of bytes sent on success, -1 on error and errno is set

       * appropriately.

       */

      ssize_t sendfds(int sockfd, const int *fds, size_t fdlen)

      {

      	char dummy[1] = {0};

      	struct iovec iov = {dummy, sizeof(dummy)};

      	char fdbuf[CMSG_SPACE(sizeof(fds[0]) * MAX_FD_LEN)];

      	struct msghdr msgh;

      	struct cmsghdr *cmsg;

      	/* just use a fixed-size buffer since we'll never send tons of fds */

      	if (fdlen > MAX_FD_LEN) {

      		errno = EINVAL;

      		return -1;

      	}

      	memset(&msgh, 0, sizeof(msgh));

      	msgh.msg_iov = &iov;

      	msgh.msg_iovlen = 1;

      	msgh.msg_control = fdbuf;

      	msgh.msg_controllen = CMSG_SPACE(sizeof(fds[0]) * fdlen);

      	cmsg = CMSG_FIRSTHDR(&msgh);

      	cmsg->cmsg_level = SOL_SOCKET;

      	cmsg->cmsg_type = SCM_RIGHTS;

      	cmsg->cmsg_len = CMSG_LEN(sizeof(fds[0]) * fdlen);

      	memcpy(CMSG_DATA(cmsg), fds, sizeof(fds[0]) * fdlen);

      	msgh.msg_controllen = cmsg->cmsg_len;

      	return sendmsg(sockfd, &msgh, 0);

      }

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				/*
				* Utility to send fds via Unix domain socket
				*
				* Copyright 2011, 2018 Yuya Nishihara <yuya@tcha.org>
				*
				* This software may be used and distributed according to the terms of the
				* GNU General Public License version 2 or any later version.
				*/

				#include <errno.h>
				#include <stdlib.h>
				#include <string.h>
				#include <sys/socket.h>
				#include <sys/types.h>

				#define MAX_FD_LEN 10

				/*
				* Sends the given fds with 1-byte dummy payload.
				*
				* Returns the number of bytes sent on success, -1 on error and errno is set
				* appropriately.
				*/
				ssize_t sendfds(int sockfd, const int *fds, size_t fdlen)
				{
				char dummy[1] = {0};
				struct iovec iov = {dummy, sizeof(dummy)};
				char fdbuf[CMSG_SPACE(sizeof(fds[0]) * MAX_FD_LEN)];
				struct msghdr msgh;
				struct cmsghdr *cmsg;

				/* just use a fixed-size buffer since we'll never send tons of fds */
				if (fdlen > MAX_FD_LEN) {
				errno = EINVAL;
				return -1;
				}

				memset(&msgh, 0, sizeof(msgh));
				msgh.msg_iov = &iov;
				msgh.msg_iovlen = 1;
				msgh.msg_control = fdbuf;
				msgh.msg_controllen = CMSG_SPACE(sizeof(fds[0]) * fdlen);

				cmsg = CMSG_FIRSTHDR(&msgh);
				cmsg->cmsg_level = SOL_SOCKET;
				cmsg->cmsg_type = SCM_RIGHTS;
				cmsg->cmsg_len = CMSG_LEN(sizeof(fds[0]) * fdlen);
				memcpy(CMSG_DATA(cmsg), fds, sizeof(fds[0]) * fdlen);
				msgh.msg_controllen = cmsg->cmsg_len;
				return sendmsg(sockfd, &msgh, 0);
				}