nuclear@22: /* file modification monitoring with inotify */
nuclear@22: #ifdef __linux__
nuclear@22: #include <stdio.h>
nuclear@22: #include <assert.h>
nuclear@22: #include <unistd.h>
nuclear@22: #include <fcntl.h>
nuclear@22: #include <sys/inotify.h>
nuclear@22: #include "filewatch.h"
nuclear@22: #include "resman.h"
nuclear@22: #include "resman_impl.h"
nuclear@22: 
nuclear@22: static void reload_modified(struct rbnode *node, void *cls);
nuclear@22: 
nuclear@22: int resman_init_file_monitor(struct resman *rman)
nuclear@22: {
nuclear@22: 	int fd;
nuclear@22: 
nuclear@22: 	if((fd = inotify_init()) == -1) {
nuclear@22: 		return -1;
nuclear@22: 	}
nuclear@22: 	/* set non-blocking flag, to allow polling by reading */
nuclear@22: 	fcntl(fd, F_SETFL, fcntl(fd, F_GETFL) | O_NONBLOCK);
nuclear@22: 	rman->inotify_fd = fd;
nuclear@22: 
nuclear@22: 	/* create the fd->resource map */
nuclear@22: 	rman->nresmap = rb_create(RB_KEY_INT);
nuclear@22: 	/* create the modified set */
nuclear@22: 	rman->modset = rb_create(RB_KEY_INT);
nuclear@22: 	return 0;
nuclear@22: }
nuclear@22: 
nuclear@22: void resman_destroy_file_monitor(struct resman *rman)
nuclear@22: {
nuclear@22: 	rb_free(rman->nresmap);
nuclear@22: 	rb_free(rman->modset);
nuclear@22: 
nuclear@22: 	if(rman->inotify_fd >= 0) {
nuclear@22: 		close(rman->inotify_fd);
nuclear@22: 		rman->inotify_fd = -1;
nuclear@22: 	}
nuclear@22: }
nuclear@22: 
nuclear@22: int resman_start_watch(struct resman *rman, struct resource *res)
nuclear@22: {
nuclear@22: 	int fd;
nuclear@22: 
nuclear@23: 	if(res->nfd > 0) {
nuclear@23: 		return 0;	/* already started a watch for this resource */
nuclear@23: 	}
nuclear@23: 
nuclear@22: 	if((fd = inotify_add_watch(rman->inotify_fd, res->name, IN_MODIFY)) == -1) {
nuclear@22: 		return -1;
nuclear@22: 	}
nuclear@22: 	printf("started watching file \"%s\" for modification (fd %d)\n", res->name, fd);
nuclear@22: 	rb_inserti(rman->nresmap, fd, res);
nuclear@22: 
nuclear@22: 	res->nfd = fd;
nuclear@22: 	return 0;
nuclear@22: }
nuclear@22: 
nuclear@22: void resman_stop_watch(struct resman *rman, struct resource *res)
nuclear@22: {
nuclear@22: 	if(res->nfd > 0) {
nuclear@22: 		rb_deletei(rman->nresmap, res->nfd);
nuclear@22: 		inotify_rm_watch(rman->inotify_fd, res->nfd);
nuclear@22: 	}
nuclear@22: }
nuclear@22: 
nuclear@22: void resman_check_watch(struct resman *rman)
nuclear@22: {
nuclear@22: 	char buf[512];
nuclear@22: 	struct inotify_event *ev;
nuclear@22: 	int sz, evsize;
nuclear@22: 
nuclear@22: 	while((sz = read(rman->inotify_fd, buf, sizeof buf)) > 0) {
nuclear@22: 		ev = (struct inotify_event*)buf;
nuclear@22: 		while(sz > 0) {
nuclear@22: 			if(ev->mask & IN_MODIFY) {
nuclear@22: 				/* add the file descriptor to the modified set */
nuclear@22: 				rb_inserti(rman->modset, ev->wd, 0);
nuclear@22: 			}
nuclear@22: 
nuclear@22: 			evsize = sizeof *ev + ev->len;
nuclear@22: 			sz -= evsize;
nuclear@22: 			ev += evsize;
nuclear@22: 		}
nuclear@22: 	}
nuclear@22: 
nuclear@22: 	/* for each item in the modified set, start a new job to reload it */
nuclear@22: 	rb_foreach(rman->modset, reload_modified, rman);
nuclear@22: 	rb_clear(rman->modset);
nuclear@22: }
nuclear@22: 
nuclear@22: /* this is called for each item in the modified set (see above) */
nuclear@22: static void reload_modified(struct rbnode *node, void *cls)
nuclear@22: {
nuclear@22: 	int watch_fd;
nuclear@22: 	struct resource *res;
nuclear@22: 	struct resman *rman = cls;
nuclear@22: 
nuclear@22: 	watch_fd = rb_node_keyi(node);
nuclear@22: 
nuclear@22: 	if(!(res = rb_findi(rman->nresmap, watch_fd))) {
nuclear@22: 		fprintf(stderr, "%s: can't find resource for watch descriptor: %d\n",
nuclear@22: 				__FUNCTION__, watch_fd);
nuclear@22: 		return;
nuclear@22: 	}
nuclear@22: 	assert(watch_fd == res->nfd);
nuclear@22: 
nuclear@22: 	printf("file \"%s\" modified (fd %d)\n", res->name, rb_node_keyi(node));
nuclear@22: 
nuclear@22: 	tpool_add_work(rman->tpool, res);
nuclear@22: }
nuclear@22: 
nuclear@22: #else
nuclear@22: int resman_filewatch_linux_silence_empty_file_warning;
nuclear@22: #endif	/* __linux__ */