From 5f722fa8f6561c964fd0bd651b4602ac0f7bc3b4 Mon Sep 17 00:00:00 2001 From: Miklos Szeredi Date: Mon, 8 Dec 2008 19:26:53 +0000 Subject: * Implement poll support. Patch by Tejun Heo --- example/.cvsignore | 2 + example/Makefile.am | 6 +- example/fsel.c | 276 +++++++++++++++++++++++++++++++++++++++++++++++++++ example/fselclient.c | 72 ++++++++++++++ 4 files changed, 355 insertions(+), 1 deletion(-) create mode 100644 example/fsel.c create mode 100644 example/fselclient.c (limited to 'example') diff --git a/example/.cvsignore b/example/.cvsignore index 7332bc0..af7dd99 100644 --- a/example/.cvsignore +++ b/example/.cvsignore @@ -8,4 +8,6 @@ hello hello_ll fioc fioclient +fsel +fselclient .libs diff --git a/example/Makefile.am b/example/Makefile.am index 43b195d..1aa5774 100644 --- a/example/Makefile.am +++ b/example/Makefile.am @@ -2,7 +2,8 @@ AM_CPPFLAGS = -I$(top_srcdir)/include -D_FILE_OFFSET_BITS=64 -D_REENTRANT noinst_HEADERS = fioc.h -noinst_PROGRAMS = fusexmp fusexmp_fh null hello hello_ll fioc fioclient +noinst_PROGRAMS = fusexmp fusexmp_fh null hello hello_ll fioc fioclient \ + fsel fselclient LDADD = ../lib/libfuse.la @libfuse_libs@ fusexmp_fh_LDADD = ../lib/libfuse.la ../lib/libulockmgr.la @libfuse_libs@ @@ -10,4 +11,7 @@ fusexmp_fh_LDADD = ../lib/libfuse.la ../lib/libulockmgr.la @libfuse_libs@ fioclient_CPPFLAGS = fioclient_LDFLAGS = fioclient_LDADD = +fselclient_CPPFLAGS = +fselclient_LDFLAGS = +fselclient_LDADD = diff --git a/example/fsel.c b/example/fsel.c new file mode 100644 index 0000000..a3c0c68 --- /dev/null +++ b/example/fsel.c @@ -0,0 +1,276 @@ +/* + FUSE fsel: FUSE select example + Copyright (C) 2008 SUSE Linux Products GmbH + Copyright (C) 2008 Tejun Heo + + This program can be distributed under the terms of the GNU GPL. + See the file COPYING. + + gcc -Wall `pkg-config fuse --cflags --libs` fsel.c -o fsel +*/ + +#define FUSE_USE_VERSION 29 + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +/* + * 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) +{ + 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) +{ + char name[2] = { }; + int i; + + (void) offset; + (void) fi; + + if (strcmp(path, "/") != 0) + return -ENOENT; + + for (i = 0; i < FSEL_FILES; i++) { + name[0] = fsel_hex_map[i]; + filler(buf, name, NULL, 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 & 3) != 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); + } +} + +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; +} diff --git a/example/fselclient.c b/example/fselclient.c new file mode 100644 index 0000000..7c4b837 --- /dev/null +++ b/example/fselclient.c @@ -0,0 +1,72 @@ +/* + FUSE fselclient: FUSE select example client + Copyright (C) 2008 SUSE Linux Products GmbH + Copyright (C) 2008 Tejun Heo + + This program can be distributed under the terms of the GNU GPL. + See the file COPYING. + + gcc -Wall fselclient.c -o fselclient +*/ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#define FSEL_FILES 16 + +int main(void) +{ + static const char hex_map[FSEL_FILES] = "0123456789ABCDEF"; + int fds[FSEL_FILES]; + int i, nfds; + + for (i = 0; i < FSEL_FILES; i++) { + char name[] = { hex_map[i], '\0' }; + fds[i] = open(name, O_RDONLY); + if (fds[i] < 0) { + perror("open"); + return 1; + } + } + nfds = fds[FSEL_FILES - 1] + 1; + + while (1) { + static char buf[4096]; + fd_set rfds; + int rc; + + FD_ZERO(&rfds); + for (i = 0; i < FSEL_FILES; i++) + FD_SET(fds[i], &rfds); + + rc = select(nfds, &rfds, NULL, NULL, NULL); + + if (rc < 0) { + perror("select"); + return 1; + } + + for (i = 0; i < FSEL_FILES; i++) { + if (!FD_ISSET(fds[i], &rfds)) { + printf("_: "); + continue; + } + printf("%X:", i); + rc = read(fds[i], buf, sizeof(buf)); + if (rc < 0) { + perror("read"); + return 1; + } + printf("%02d ", rc); + } + printf("\n"); + } +} -- cgit v1.2.3