From: Michael Tremer <michael.tremer@ipfire.org>
Date: Sat, 2 Dec 2023 12:57:13 +0000 (+0000)
Subject: jail: Bring back helper function to add FDs to epoll()
X-Git-Url: http://git.ipfire.org/?p=pakfire.git;a=commitdiff_plain;h=e4fded3aef04ad36c7f3db29b486e0c6a4fb937e

jail: Bring back helper function to add FDs to epoll()

Signed-off-by: Michael Tremer <michael.tremer@ipfire.org>
---

diff --git a/src/libpakfire/jail.c b/src/libpakfire/jail.c
index 00630daf..5cc1dd75 100644
--- a/src/libpakfire/jail.c
+++ b/src/libpakfire/jail.c
@@ -743,9 +743,39 @@ static int pakfire_jail_log(struct pakfire* pakfire, void* data, int priority,
 	return 0;
 }
 
+static int pakfire_jail_epoll_add_fd(struct pakfire_jail* jail, int epollfd, int fd, int events) {
+	struct epoll_event event = {
+		.events = events|EPOLLHUP,
+		.data   = {
+			.fd = fd,
+		},
+	};
+	int r;
+
+	// Read flags
+	int flags = fcntl(fd, F_GETFL, 0);
+
+	// Set modified flags
+	r  = fcntl(fd, F_SETFL, flags|O_NONBLOCK);
+	if (r < 0) {
+		CTX_ERROR(jail->ctx, "Could not set file descriptor %d into non-blocking mode: %s\n",
+			fd, strerror(errno));
+		return -errno;
+	}
+
+	// Add the file descriptor to the loop
+	r = epoll_ctl(epollfd, EPOLL_CTL_ADD, fd, &event);
+	if (r < 0) {
+		ERROR(jail->pakfire, "Could not add file descriptor %d to epoll(): %s\n",
+			fd, strerror(errno));
+		return -errno;
+	}
+
+	return 0;
+}
+
 static int pakfire_jail_wait(struct pakfire_jail* jail, struct pakfire_jail_exec* ctx) {
 	int epollfd = -1;
-	struct epoll_event ev;
 	struct epoll_event events[EPOLL_MAX_EVENTS];
 	char garbage[8];
 	int r = 0;
@@ -767,17 +797,30 @@ static int pakfire_jail_wait(struct pakfire_jail* jail, struct pakfire_jail_exec
 #endif /* ENABLE_DEBUG */
 
 	// Make a list of all file descriptors we are interested in
-	const int fds[] = {
-		stdin,
-		stdout,
-		stderr,
-		pidfd,
-		timerfd,
-		log_INFO,
-		log_ERROR,
+	const struct pakfire_wait_fds {
+		const int fd;
+		const int events;
+	} fds[] = {
+		// Standard input/output
+		{ stdin,  EPOLLOUT },
+		{ stdout, EPOLLIN },
+		{ stderr, EPOLLIN },
+
+		// Timer
+		{ timerfd, EPOLLIN },
+
+		// Child Process
+		{ ctx->pidfd, EPOLLIN },
+
+		// Log Pipes
+		{ log_INFO, EPOLLIN },
+		{ log_ERROR, EPOLLIN },
 #ifdef ENABLE_DEBUG
-		log_DEBUG,
+		{ log_DEBUG, EPOLLIN },
 #endif /* ENABLE_DEBUG */
+
+		// Sentinel
+		{ -1, 0 },
 	};
 
 	// Setup epoll
@@ -789,38 +832,15 @@ static int pakfire_jail_wait(struct pakfire_jail* jail, struct pakfire_jail_exec
 	}
 
 	// Turn file descriptors into non-blocking mode and add them to epoll()
-	for (unsigned int i = 0; i < sizeof(fds) / sizeof(*fds); i++) {
-		int fd = fds[i];
-
+	for (const struct pakfire_wait_fds* fd = fds; fd->events; fd++) {
 		// Skip fds which were not initialized
-		if (fd < 0)
+		if (fd->fd < 0)
 			continue;
 
-		ev.events = EPOLLHUP;
-
-		if (fd == stdin)
-			ev.events |= EPOLLOUT;
-		else
-			ev.events |= EPOLLIN;
-
-		// Read flags
-		int flags = fcntl(fd, F_GETFL, 0);
-
-		// Set modified flags
-		if (fcntl(fd, F_SETFL, flags|O_NONBLOCK) < 0) {
-			ERROR(jail->pakfire,
-				"Could not set file descriptor %d into non-blocking mode: %m\n", fd);
-			r = 1;
-			goto ERROR;
-		}
-
-		ev.data.fd = fd;
-
-		if (epoll_ctl(epollfd, EPOLL_CTL_ADD, fd, &ev) < 0) {
-			ERROR(jail->pakfire, "Could not add file descriptor %d to epoll(): %m\n", fd);
-			r = 1;
+		// Add the FD to the event loop
+		r = pakfire_jail_epoll_add_fd(jail, epollfd, fd->fd, fd->events);
+		if (r)
 			goto ERROR;
-		}
 	}
 
 	int ended = 0;