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-rw-r--r--example/poll.c296
1 files changed, 0 insertions, 296 deletions
diff --git a/example/poll.c b/example/poll.c
deleted file mode 100644
index 64917cc..0000000
--- a/example/poll.c
+++ /dev/null
@@ -1,296 +0,0 @@
-/*
- FUSE fsel: FUSE select example
- Copyright (C) 2008 SUSE Linux Products GmbH
- Copyright (C) 2008 Tejun Heo <teheo@suse.de>
-
- This program can be distributed under the terms of the GNU GPL.
- See the file COPYING.
-*/
-
-/** @file
- *
- * This example illustrates how to write a FUSE file system that
- * supports polling for changes that don't come through the kernel. It
- * can be tested with the poll_client.c program.
- *
- * Compile with:
- *
- * gcc -Wall poll.c `pkg-config fuse3 --cflags --libs` -o poll
- *
- * ## Source code ##
- * \include poll.c
- */
-
-#define FUSE_USE_VERSION 31
-
-#include <config.h>
-
-#include <fuse.h>
-#include <unistd.h>
-#include <ctype.h>
-#include <string.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <errno.h>
-#include <time.h>
-#include <pthread.h>
-#include <poll.h>
-
-/*
- * fsel_open_mask is used to limit the number of opens to 1 per file.
- * This is to use file index (0-F) as fh as poll support requires
- * unique fh per open file. Lifting this would require proper open
- * file management.
- */
-static unsigned fsel_open_mask;
-static const char fsel_hex_map[] = "0123456789ABCDEF";
-static struct fuse *fsel_fuse; /* needed for poll notification */
-
-#define FSEL_CNT_MAX 10 /* each file can store upto 10 chars */
-#define FSEL_FILES 16
-
-static pthread_mutex_t fsel_mutex; /* protects notify_mask and cnt array */
-static unsigned fsel_poll_notify_mask; /* poll notification scheduled? */
-static struct fuse_pollhandle *fsel_poll_handle[FSEL_FILES]; /* poll notify handles */
-static unsigned fsel_cnt[FSEL_FILES]; /* nbytes stored in each file */
-
-static int fsel_path_index(const char *path)
-{
- char ch = path[1];
-
- if (strlen(path) != 2 || path[0] != '/' || !isxdigit(ch) || islower(ch))
- return -1;
- return ch <= '9' ? ch - '0' : ch - 'A' + 10;
-}
-
-static int fsel_getattr(const char *path, struct stat *stbuf,
- struct fuse_file_info *fi)
-{
- (void) fi;
- int idx;
-
- memset(stbuf, 0, sizeof(struct stat));
-
- if (strcmp(path, "/") == 0) {
- stbuf->st_mode = S_IFDIR | 0555;
- stbuf->st_nlink = 2;
- return 0;
- }
-
- idx = fsel_path_index(path);
- if (idx < 0)
- return -ENOENT;
-
- stbuf->st_mode = S_IFREG | 0444;
- stbuf->st_nlink = 1;
- stbuf->st_size = fsel_cnt[idx];
- return 0;
-}
-
-static int fsel_readdir(const char *path, void *buf, fuse_fill_dir_t filler,
- off_t offset, struct fuse_file_info *fi,
- enum fuse_readdir_flags flags)
-{
- char name[2] = { };
- int i;
-
- (void) offset;
- (void) fi;
- (void) flags;
-
- if (strcmp(path, "/") != 0)
- return -ENOENT;
-
- for (i = 0; i < FSEL_FILES; i++) {
- name[0] = fsel_hex_map[i];
- filler(buf, name, NULL, 0, 0);
- }
-
- return 0;
-}
-
-static int fsel_open(const char *path, struct fuse_file_info *fi)
-{
- int idx = fsel_path_index(path);
-
- if (idx < 0)
- return -ENOENT;
- if ((fi->flags & O_ACCMODE) != O_RDONLY)
- return -EACCES;
- if (fsel_open_mask & (1 << idx))
- return -EBUSY;
- fsel_open_mask |= (1 << idx);
-
- /*
- * fsel files are nonseekable somewhat pipe-like files which
- * gets filled up periodically by producer thread and consumed
- * on read. Tell FUSE as such.
- */
- fi->fh = idx;
- fi->direct_io = 1;
- fi->nonseekable = 1;
-
- return 0;
-}
-
-static int fsel_release(const char *path, struct fuse_file_info *fi)
-{
- int idx = fi->fh;
-
- (void) path;
-
- fsel_open_mask &= ~(1 << idx);
- return 0;
-}
-
-static int fsel_read(const char *path, char *buf, size_t size, off_t offset,
- struct fuse_file_info *fi)
-{
- int idx = fi->fh;
-
- (void) path;
- (void) offset;
-
- pthread_mutex_lock(&fsel_mutex);
- if (fsel_cnt[idx] < size)
- size = fsel_cnt[idx];
- printf("READ %X transferred=%zu cnt=%u\n", idx, size, fsel_cnt[idx]);
- fsel_cnt[idx] -= size;
- pthread_mutex_unlock(&fsel_mutex);
-
- memset(buf, fsel_hex_map[idx], size);
- return size;
-}
-
-static int fsel_poll(const char *path, struct fuse_file_info *fi,
- struct fuse_pollhandle *ph, unsigned *reventsp)
-{
- static unsigned polled_zero;
- int idx = fi->fh;
-
- (void) path;
-
- /*
- * Poll notification requires pointer to struct fuse which
- * can't be obtained when using fuse_main(). As notification
- * happens only after poll is called, fill it here from
- * fuse_context.
- */
- if (!fsel_fuse) {
- struct fuse_context *cxt = fuse_get_context();
- if (cxt)
- fsel_fuse = cxt->fuse;
- }
-
- pthread_mutex_lock(&fsel_mutex);
-
- if (ph != NULL) {
- struct fuse_pollhandle *oldph = fsel_poll_handle[idx];
-
- if (oldph)
- fuse_pollhandle_destroy(oldph);
-
- fsel_poll_notify_mask |= (1 << idx);
- fsel_poll_handle[idx] = ph;
- }
-
- if (fsel_cnt[idx]) {
- *reventsp |= POLLIN;
- printf("POLL %X cnt=%u polled_zero=%u\n",
- idx, fsel_cnt[idx], polled_zero);
- polled_zero = 0;
- } else
- polled_zero++;
-
- pthread_mutex_unlock(&fsel_mutex);
- return 0;
-}
-
-static struct fuse_operations fsel_oper = {
- .getattr = fsel_getattr,
- .readdir = fsel_readdir,
- .open = fsel_open,
- .release = fsel_release,
- .read = fsel_read,
- .poll = fsel_poll,
-};
-
-static void *fsel_producer(void *data)
-{
- const struct timespec interval = { 0, 250000000 };
- unsigned idx = 0, nr = 1;
-
- (void) data;
-
- while (1) {
- int i, t;
-
- pthread_mutex_lock(&fsel_mutex);
-
- /*
- * This is the main producer loop which is executed
- * ever 500ms. On each iteration, it fills one byte
- * to 1, 2 or 4 files and sends poll notification if
- * requested.
- */
- for (i = 0, t = idx; i < nr;
- i++, t = (t + FSEL_FILES / nr) % FSEL_FILES) {
- if (fsel_cnt[t] == FSEL_CNT_MAX)
- continue;
-
- fsel_cnt[t]++;
- if (fsel_fuse && (fsel_poll_notify_mask & (1 << t))) {
- struct fuse_pollhandle *ph;
-
- printf("NOTIFY %X\n", t);
- ph = fsel_poll_handle[t];
- fuse_notify_poll(ph);
- fuse_pollhandle_destroy(ph);
- fsel_poll_notify_mask &= ~(1 << t);
- fsel_poll_handle[t] = NULL;
- }
- }
-
- idx = (idx + 1) % FSEL_FILES;
- if (idx == 0)
- nr = (nr * 2) % 7; /* cycle through 1, 2 and 4 */
-
- pthread_mutex_unlock(&fsel_mutex);
-
- nanosleep(&interval, NULL);
- }
-
- return NULL;
-}
-
-int main(int argc, char *argv[])
-{
- pthread_t producer;
- pthread_attr_t attr;
- int ret;
-
- errno = pthread_mutex_init(&fsel_mutex, NULL);
- if (errno) {
- perror("pthread_mutex_init");
- return 1;
- }
-
- errno = pthread_attr_init(&attr);
- if (errno) {
- perror("pthread_attr_init");
- return 1;
- }
-
- errno = pthread_create(&producer, &attr, fsel_producer, NULL);
- if (errno) {
- perror("pthread_create");
- return 1;
- }
-
- ret = fuse_main(argc, argv, &fsel_oper, NULL);
-
- pthread_cancel(producer);
- pthread_join(producer, NULL);
-
- return ret;
-}
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