dev/filemon/filemon.c

27 __KERNEL_RCSID(0, "$NetBSD: filemon.c,v 1.3 2011/07/04 23:37:30 sjg Exp $");
45 #include "filemon.h"
47 MODULE(MODULE_CLASS_DRIVER, filemon, NULL);
81 static TAILQ_HEAD(, filemon) filemons_inuse =
89 filemon_output(struct filemon * filemon, char *msg, size_t len)
94 	if (filemon->fm_fp == NULL)
118 	(*filemon->fm_fp->f_ops->fo_write) (filemon->fm_fp,
119 	    &(filemon->fm_fp->f_offset),
124 filemon_comment(struct filemon * filemon)
128 	len = snprintf(filemon->fm_msgbufr, sizeof(filemon->fm_msgbufr),
129 	    "# filemon version %d\n# Target pid %d\nV %d\n",
132 	filemon_output(filemon, filemon->fm_msgbufr, len);
136 static struct filemon *
139 	struct filemon *filemon;
141 	TAILQ_FOREACH(filemon, &filemons_inuse, fm_link) {
142 		if (p->p_pid == filemon->fm_pid)
143 			return (filemon);
153  * return exclusive access to a filemon struct
155 struct filemon *
158 	struct filemon *filemon;
161 	filemon = filemon_pid_check(p);
162 	if (filemon) {
163 		rw_enter(&filemon->fm_mtx, RW_WRITER);
166 	return filemon;
169 static struct filemon *
172 	struct filemon *filemon;
175 	filemon = fp->f_data;
176 	if (filemon && lck) {
177 		rw_enter(&filemon->fm_mtx, lck);
180 	return filemon;
189 	struct filemon *filemon;
197 	filemon = kmem_alloc(sizeof(struct filemon), KM_SLEEP);
198 	rw_init(&filemon->fm_mtx);
199 	filemon->fm_fd = -1;
200 	filemon->fm_fp = NULL;
201 	filemon->fm_pid = curproc->p_pid;
204 	TAILQ_INSERT_TAIL(&filemons_inuse, filemon, fm_link);
208 	return fd_clone(fp, fd, oflags, &filemon_fileops, filemon);
215 	struct filemon *filemon;
226 	filemon = fp->f_data;
227 	if (!filemon) {
232 	TAILQ_REMOVE(&filemons_inuse, filemon, fm_link);
240 	rw_enter(&filemon->fm_mtx, RW_WRITER);
241 	if (filemon->fm_fp) {
242 		fd_putfile(filemon->fm_fd);	/* release our reference */
243 		filemon->fm_fp = NULL;
245 	rw_exit(&filemon->fm_mtx);
246 	rw_destroy(&filemon->fm_mtx);
247 	kmem_free(filemon, sizeof(struct filemon));
256 	struct filemon *filemon;
264 	 * this ensures we cannot get filemon if it is closing.
266 	filemon = filemon_fp_data(fp, RW_WRITER);
267 	if (!filemon)
273 		filemon->fm_fd = *((int *) data);
274 		if ((filemon->fm_fp = fd_getfile(filemon->fm_fd)) == NULL) {
275 			rw_exit(&filemon->fm_mtx);
279 		filemon_comment(filemon);
284 		filemon->fm_pid = *((pid_t *) data);
292 	rw_exit(&filemon->fm_mtx);
352 		error = devsw_attach("filemon", NULL, &bmajor,
363 		log(LOG_INFO, "filemon: open=%d", n_open);