Merge commit 'a302c65dc65896776d6cb9e2c89a6ccc77ada530' as 'third-party/libuv'

third-party/libuv/src/fs-poll.c

@@ -0,0 +1,223 @@
+/* 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, int status);
+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;
+
+  if (uv__is_active(handle))
+    return 0;
+
+  loop = handle->loop;
+  len = strlen(path);
+  ctx = 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);
+
+  if (uv_timer_init(loop, &ctx->timer_handle))
+    abort();
+
+  ctx->timer_handle.flags |= UV__HANDLE_INTERNAL;
+  uv__handle_unref(&ctx->timer_handle);
+
+  if (uv_fs_stat(loop, &ctx->fs_req, ctx->path, poll_cb))
+    abort();
+
+  handle->poll_ctx = ctx;
+  uv__handle_start(handle);
+
+  return 0;
+}
+
+
+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;
+}
+
+
+void uv__fs_poll_close(uv_fs_poll_t* handle) {
+  uv_fs_poll_stop(handle);
+}
+
+
+static void timer_cb(uv_timer_t* timer, int status) {
+  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) {
+  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 */