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Diffstat (limited to 'draft/fuse-examples/fioc.c')
| -rw-r--r-- | draft/fuse-examples/fioc.c | 211 |
1 files changed, 211 insertions, 0 deletions
diff --git a/draft/fuse-examples/fioc.c b/draft/fuse-examples/fioc.c new file mode 100644 index 0000000..bee40b9 --- /dev/null +++ b/draft/fuse-examples/fioc.c @@ -0,0 +1,211 @@ +/* + FUSE fioc: FUSE ioctl 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. + + gcc -Wall fioc.c `pkg-config fuse --cflags --libs` -o fioc +*/ + +#define FUSE_USE_VERSION 26 + +#include <fuse.h> +#include <stdlib.h> +#include <stdio.h> +#include <string.h> +#include <unistd.h> +#include <time.h> +#include <errno.h> + +#include "fioc.h" + +#define FIOC_NAME "fioc" + +enum { + FIOC_NONE, + FIOC_ROOT, + FIOC_FILE, +}; + +static void *fioc_buf; +static size_t fioc_size; + +static int fioc_resize(size_t new_size) +{ + void *new_buf; + + if (new_size == fioc_size) + return 0; + + new_buf = realloc(fioc_buf, new_size); + if (!new_buf && new_size) + return -ENOMEM; + + if (new_size > fioc_size) + memset(new_buf + fioc_size, 0, new_size - fioc_size); + + fioc_buf = new_buf; + fioc_size = new_size; + + return 0; +} + +static int fioc_expand(size_t new_size) +{ + if (new_size > fioc_size) + return fioc_resize(new_size); + return 0; +} + +static int fioc_file_type(const char *path) +{ + if (strcmp(path, "/") == 0) + return FIOC_ROOT; + if (strcmp(path, "/" FIOC_NAME) == 0) + return FIOC_FILE; + return FIOC_NONE; +} + +static int fioc_getattr(const char *path, struct stat *stbuf) +{ + stbuf->st_uid = getuid(); + stbuf->st_gid = getgid(); + stbuf->st_atime = stbuf->st_mtime = time(NULL); + + switch (fioc_file_type(path)) { + case FIOC_ROOT: + stbuf->st_mode = S_IFDIR | 0755; + stbuf->st_nlink = 2; + break; + case FIOC_FILE: + stbuf->st_mode = S_IFREG | 0644; + stbuf->st_nlink = 1; + stbuf->st_size = fioc_size; + break; + case FIOC_NONE: + return -ENOENT; + } + + return 0; +} + +static int fioc_open(const char *path, struct fuse_file_info *fi) +{ + (void) fi; + + if (fioc_file_type(path) != FIOC_NONE) + return 0; + return -ENOENT; +} + +static int fioc_do_read(char *buf, size_t size, off_t offset) +{ + if (offset >= fioc_size) + return 0; + + if (size > fioc_size - offset) + size = fioc_size - offset; + + memcpy(buf, fioc_buf + offset, size); + + return size; +} + +static int fioc_read(const char *path, char *buf, size_t size, + off_t offset, struct fuse_file_info *fi) +{ + (void) fi; + + if (fioc_file_type(path) != FIOC_FILE) + return -EINVAL; + + return fioc_do_read(buf, size, offset); +} + +static int fioc_do_write(const char *buf, size_t size, off_t offset) +{ + if (fioc_expand(offset + size)) + return -ENOMEM; + + memcpy(fioc_buf + offset, buf, size); + + return size; +} + +static int fioc_write(const char *path, const char *buf, size_t size, + off_t offset, struct fuse_file_info *fi) +{ + (void) fi; + + if (fioc_file_type(path) != FIOC_FILE) + return -EINVAL; + + return fioc_do_write(buf, size, offset); +} + +static int fioc_truncate(const char *path, off_t size) +{ + if (fioc_file_type(path) != FIOC_FILE) + return -EINVAL; + + return fioc_resize(size); +} + +static int fioc_readdir(const char *path, void *buf, fuse_fill_dir_t filler, + off_t offset, struct fuse_file_info *fi) +{ + (void) fi; + (void) offset; + + if (fioc_file_type(path) != FIOC_ROOT) + return -ENOENT; + + filler(buf, ".", NULL, 0); + filler(buf, "..", NULL, 0); + filler(buf, FIOC_NAME, NULL, 0); + + return 0; +} + +static int fioc_ioctl(const char *path, int cmd, void *arg, + struct fuse_file_info *fi, unsigned int flags, void *data) +{ + (void) arg; + (void) fi; + (void) flags; + + if (fioc_file_type(path) != FIOC_FILE) + return -EINVAL; + + if (flags & FUSE_IOCTL_COMPAT) + return -ENOSYS; + + switch (cmd) { + case FIOC_GET_SIZE: + *(size_t *)data = fioc_size; + return 0; + + case FIOC_SET_SIZE: + fioc_resize(*(size_t *)data); + return 0; + } + + return -EINVAL; +} + +static struct fuse_operations fioc_oper = { + .getattr = fioc_getattr, + .readdir = fioc_readdir, + .truncate = fioc_truncate, + .open = fioc_open, + .read = fioc_read, + .write = fioc_write, + .ioctl = fioc_ioctl, +}; + +int main(int argc, char *argv[]) +{ + return fuse_main(argc, argv, &fioc_oper, NULL); +} |