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/* Copyright Joyent, Inc. and other Node contributors. All rights reserved.
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to
* deal in the Software without restriction, including without limitation the
* rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
* sell copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
* IN THE SOFTWARE.
*/
#include "uv.h"
#include "uv-common.h"
#include <assert.h>
#include <stdlib.h>
#include <string.h>
struct poll_ctx {
uv_fs_poll_t* parent_handle; /* NULL if parent has been stopped or closed */
int busy_polling;
unsigned int interval;
uint64_t start_time;
uv_loop_t* loop;
uv_fs_poll_cb poll_cb;
uv_timer_t timer_handle;
uv_fs_t fs_req; /* TODO(bnoordhuis) mark fs_req internal */
uv_stat_t statbuf;
char path[1]; /* variable length */
};
static int statbuf_eq(const uv_stat_t* a, const uv_stat_t* b);
static void poll_cb(uv_fs_t* req);
static void timer_cb(uv_timer_t* timer);
static void timer_close_cb(uv_handle_t* handle);
static uv_stat_t zero_statbuf;
int uv_fs_poll_init(uv_loop_t* loop, uv_fs_poll_t* handle) {
uv__handle_init(loop, (uv_handle_t*)handle, UV_FS_POLL);
return 0;
}
int uv_fs_poll_start(uv_fs_poll_t* handle,
uv_fs_poll_cb cb,
const char* path,
unsigned int interval) {
struct poll_ctx* ctx;
uv_loop_t* loop;
size_t len;
int err;
if (uv__is_active(handle))
return 0;
loop = handle->loop;
len = strlen(path);
ctx = uv__calloc(1, sizeof(*ctx) + len);
if (ctx == NULL)
return UV_ENOMEM;
ctx->loop = loop;
ctx->poll_cb = cb;
ctx->interval = interval ? interval : 1;
ctx->start_time = uv_now(loop);
ctx->parent_handle = handle;
memcpy(ctx->path, path, len + 1);
err = uv_timer_init(loop, &ctx->timer_handle);
if (err < 0)
goto error;
ctx->timer_handle.flags |= UV_HANDLE_INTERNAL;
uv__handle_unref(&ctx->timer_handle);
err = uv_fs_stat(loop, &ctx->fs_req, ctx->path, poll_cb);
if (err < 0)
goto error;
handle->poll_ctx = ctx;
uv__handle_start(handle);
return 0;
error:
uv__free(ctx);
return err;
}
int uv_fs_poll_stop(uv_fs_poll_t* handle) {
struct poll_ctx* ctx;
if (!uv__is_active(handle))
return 0;
ctx = handle->poll_ctx;
assert(ctx != NULL);
assert(ctx->parent_handle != NULL);
ctx->parent_handle = NULL;
handle->poll_ctx = NULL;
/* Close the timer if it's active. If it's inactive, there's a stat request
* in progress and poll_cb will take care of the cleanup.
*/
if (uv__is_active(&ctx->timer_handle))
uv_close((uv_handle_t*)&ctx->timer_handle, timer_close_cb);
uv__handle_stop(handle);
return 0;
}
int uv_fs_poll_getpath(uv_fs_poll_t* handle, char* buffer, size_t* size) {
struct poll_ctx* ctx;
size_t required_len;
if (!uv__is_active(handle)) {
*size = 0;
return UV_EINVAL;
}
ctx = handle->poll_ctx;
assert(ctx != NULL);
required_len = strlen(ctx->path);
if (required_len >= *size) {
*size = required_len + 1;
return UV_ENOBUFS;
}
memcpy(buffer, ctx->path, required_len);
*size = required_len;
buffer[required_len] = '\0';
return 0;
}
void uv__fs_poll_close(uv_fs_poll_t* handle) {
uv_fs_poll_stop(handle);
}
static void timer_cb(uv_timer_t* timer) {
struct poll_ctx* ctx;
ctx = container_of(timer, struct poll_ctx, timer_handle);
assert(ctx->parent_handle != NULL);
assert(ctx->parent_handle->poll_ctx == ctx);
ctx->start_time = uv_now(ctx->loop);
if (uv_fs_stat(ctx->loop, &ctx->fs_req, ctx->path, poll_cb))
abort();
}
static void poll_cb(uv_fs_t* req) {
uv_stat_t* statbuf;
struct poll_ctx* ctx;
uint64_t interval;
ctx = container_of(req, struct poll_ctx, fs_req);
if (ctx->parent_handle == NULL) { /* handle has been stopped or closed */
uv_close((uv_handle_t*)&ctx->timer_handle, timer_close_cb);
uv_fs_req_cleanup(req);
return;
}
if (req->result != 0) {
if (ctx->busy_polling != req->result) {
ctx->poll_cb(ctx->parent_handle,
req->result,
&ctx->statbuf,
&zero_statbuf);
ctx->busy_polling = req->result;
}
goto out;
}
statbuf = &req->statbuf;
if (ctx->busy_polling != 0)
if (ctx->busy_polling < 0 || !statbuf_eq(&ctx->statbuf, statbuf))
ctx->poll_cb(ctx->parent_handle, 0, &ctx->statbuf, statbuf);
ctx->statbuf = *statbuf;
ctx->busy_polling = 1;
out:
uv_fs_req_cleanup(req);
if (ctx->parent_handle == NULL) { /* handle has been stopped by callback */
uv_close((uv_handle_t*)&ctx->timer_handle, timer_close_cb);
return;
}
/* Reschedule timer, subtract the delay from doing the stat(). */
interval = ctx->interval;
interval -= (uv_now(ctx->loop) - ctx->start_time) % interval;
if (uv_timer_start(&ctx->timer_handle, timer_cb, interval, 0))
abort();
}
static void timer_close_cb(uv_handle_t* handle) {
uv__free(container_of(handle, struct poll_ctx, timer_handle));
}
static int statbuf_eq(const uv_stat_t* a, const uv_stat_t* b) {
return a->st_ctim.tv_nsec == b->st_ctim.tv_nsec
&& a->st_mtim.tv_nsec == b->st_mtim.tv_nsec
&& a->st_birthtim.tv_nsec == b->st_birthtim.tv_nsec
&& a->st_ctim.tv_sec == b->st_ctim.tv_sec
&& a->st_mtim.tv_sec == b->st_mtim.tv_sec
&& a->st_birthtim.tv_sec == b->st_birthtim.tv_sec
&& a->st_size == b->st_size
&& a->st_mode == b->st_mode
&& a->st_uid == b->st_uid
&& a->st_gid == b->st_gid
&& a->st_ino == b->st_ino
&& a->st_dev == b->st_dev
&& a->st_flags == b->st_flags
&& a->st_gen == b->st_gen;
}
#if defined(_WIN32)
#include "win/internal.h"
#include "win/handle-inl.h"
void uv__fs_poll_endgame(uv_loop_t* loop, uv_fs_poll_t* handle) {
assert(handle->flags & UV_HANDLE_CLOSING);
assert(!(handle->flags & UV_HANDLE_CLOSED));
uv__handle_close(handle);
}
#endif /* _WIN32 */
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