Commit cc671a2d40
Changed files (1)
lib
std
Build
lib/std/Build/Watch.zig
@@ -605,7 +605,16 @@ const Os = switch (builtin.os.tag) {
kq_fd: i32,
/// Indexes correspond 1:1 with `dir_table`.
- reaction_sets: std.ArrayListUnmanaged(ReactionSet),
+ handles: std.MultiArrayList(struct {
+ rs: ReactionSet,
+ /// If the corresponding dir_table Path has sub_path == "", then it
+ /// suffices as the open directory handle, and this value will be
+ /// -1. Otherwise, it needs to be opened in update(), and will be
+ /// stored here.
+ dir_fd: i32,
+ /// Number of files being watched by this directory handle.
+ ref_count: u32,
+ }),
const dir_open_flags: posix.O = f: {
var f: posix.O = .{
@@ -619,6 +628,9 @@ const Os = switch (builtin.os.tag) {
break :f f;
};
+ const EV = std.c.EV;
+ const NOTE = std.c.NOTE;
+
fn init() !Watch {
const kq_fd = try posix.kqueue();
errdefer posix.close(kq_fd);
@@ -626,27 +638,29 @@ const Os = switch (builtin.os.tag) {
.dir_table = .{},
.os = .{
.kq_fd = kq_fd,
- .reaction_sets = .{},
+ .handles = .empty,
},
.generation = 0,
};
}
fn update(w: *Watch, gpa: Allocator, steps: []const *Step) !void {
+ const handles = &w.os.handles;
for (steps) |step| {
for (step.inputs.table.keys(), step.inputs.table.values()) |path, *files| {
const reaction_set = rs: {
const gop = try w.dir_table.getOrPut(gpa, path);
if (!gop.found_existing) {
- const dir_fd = if (path.sub_path.len == 0)
+ const skip_open_dir = path.sub_path.len == 0;
+ const dir_fd = if (skip_open_dir)
path.root_dir.handle.fd
else
posix.openat(path.root_dir.handle.fd, path.sub_path, dir_open_flags, 0) catch |err| {
fatal("failed to open directory {}: {s}", .{ path, @errorName(err) });
};
- const EV = std.c.EV;
- const NOTE = std.c.NOTE;
- var changes = [1]posix.Kevent{.{
+ // Empirically the dir has to stay open or else no events are triggered.
+ errdefer if (!skip_open_dir) posix.close(dir_fd);
+ const changes = [1]posix.Kevent{.{
.ident = @bitCast(@as(isize, dir_fd)),
.filter = std.c.EVFILT.VNODE,
.flags = EV.ADD | EV.ENABLE | EV.CLEAR,
@@ -655,12 +669,16 @@ const Os = switch (builtin.os.tag) {
.udata = gop.index,
}};
_ = try posix.kevent(w.os.kq_fd, &changes, &.{}, null);
- assert(w.os.reaction_sets.items.len == gop.index);
- const reaction_set = try w.os.reaction_sets.addOne(gpa);
- reaction_set.* = .{};
- break :rs reaction_set;
+ assert(handles.len == gop.index);
+ try handles.append(gpa, .{
+ .rs = .{},
+ .dir_fd = if (skip_open_dir) -1 else dir_fd,
+ .ref_count = 1,
+ });
+ } else {
+ handles.items(.ref_count)[gop.index] += 1;
}
- break :rs &w.os.reaction_sets.items[gop.index];
+ break :rs &handles.items(.rs)[gop.index];
};
for (files.items) |basename| {
const gop = try reaction_set.getOrPut(gpa, basename);
@@ -672,47 +690,86 @@ const Os = switch (builtin.os.tag) {
{
// Remove marks for files that are no longer inputs.
- //var i: usize = 0;
- //while (i < w.os.handle_table.entries.len) {
- // {
- // const reaction_set = &w.os.handle_table.values()[i];
- // var step_set_i: usize = 0;
- // while (step_set_i < reaction_set.entries.len) {
- // const step_set = &reaction_set.values()[step_set_i];
- // var dirent_i: usize = 0;
- // while (dirent_i < step_set.entries.len) {
- // const generations = step_set.values();
- // if (generations[dirent_i] == w.generation) {
- // dirent_i += 1;
- // continue;
- // }
- // step_set.swapRemoveAt(dirent_i);
- // }
- // if (step_set.entries.len > 0) {
- // step_set_i += 1;
- // continue;
- // }
- // reaction_set.swapRemoveAt(step_set_i);
- // }
- // if (reaction_set.entries.len > 0) {
- // i += 1;
- // continue;
- // }
- // }
-
- // const path = w.dir_table.keys()[i];
-
- // posix.fanotify_mark(fan_fd, .{
- // .REMOVE = true,
- // .ONLYDIR = true,
- // }, fan_mask, path.root_dir.handle.fd, path.subPathOrDot()) catch |err| switch (err) {
- // error.FileNotFound => {}, // Expected, harmless.
- // else => |e| std.log.warn("unable to unwatch '{}': {s}", .{ path, @errorName(e) }),
- // };
-
- // w.dir_table.swapRemoveAt(i);
- // w.os.handle_table.swapRemoveAt(i);
- //}
+ var i: usize = 0;
+ while (i < handles.len) {
+ {
+ const reaction_set = &handles.items(.rs)[i];
+ var step_set_i: usize = 0;
+ while (step_set_i < reaction_set.entries.len) {
+ const step_set = &reaction_set.values()[step_set_i];
+ var dirent_i: usize = 0;
+ while (dirent_i < step_set.entries.len) {
+ const generations = step_set.values();
+ if (generations[dirent_i] == w.generation) {
+ dirent_i += 1;
+ continue;
+ }
+ step_set.swapRemoveAt(dirent_i);
+ }
+ if (step_set.entries.len > 0) {
+ step_set_i += 1;
+ continue;
+ }
+ reaction_set.swapRemoveAt(step_set_i);
+ }
+ if (reaction_set.entries.len > 0) {
+ i += 1;
+ continue;
+ }
+ }
+
+ const ref_count_ptr = &handles.items(.ref_count)[i];
+ ref_count_ptr.* -= 1;
+ if (ref_count_ptr.* > 0) continue;
+
+ // If the sub_path == "" then this patch has already the
+ // dir fd that we need to use as the ident to remove the
+ // event. If it was opened above with openat() then we need
+ // to access that data via the dir_fd field.
+ const path = w.dir_table.keys()[i];
+ const dir_fd = if (path.sub_path.len == 0)
+ path.root_dir.handle.fd
+ else
+ handles.items(.dir_fd)[i];
+ assert(dir_fd != -1);
+
+ // The changelist also needs to update the udata field of the last
+ // event, since we are doing a swap remove, and we store the dir_table
+ // index in the udata field.
+ const last_dir_fd = fd: {
+ const last_path = w.dir_table.keys()[handles.len - 1];
+ const last_dir_fd = if (last_path.sub_path.len != 0)
+ last_path.root_dir.handle.fd
+ else
+ handles.items(.dir_fd)[i];
+ assert(last_dir_fd != -1);
+ break :fd last_dir_fd;
+ };
+ const changes = [_]posix.Kevent{
+ .{
+ .ident = @bitCast(@as(isize, dir_fd)),
+ .filter = std.c.EVFILT.VNODE,
+ .flags = EV.DELETE,
+ .fflags = 0,
+ .data = 0,
+ .udata = i,
+ },
+ .{
+ .ident = @bitCast(@as(isize, last_dir_fd)),
+ .filter = std.c.EVFILT.VNODE,
+ .flags = EV.ADD,
+ .fflags = NOTE.DELETE | NOTE.WRITE | NOTE.RENAME | NOTE.REVOKE,
+ .data = 0,
+ .udata = i,
+ },
+ };
+ const filtered_changes = if (i == handles.len - 1) changes[0..1] else &changes;
+ _ = try posix.kevent(w.os.kq_fd, filtered_changes, &.{}, null);
+ if (path.sub_path.len != 0) posix.close(dir_fd);
+
+ w.dir_table.swapRemoveAt(i);
+ handles.swapRemove(i);
+ }
w.generation +%= 1;
}
}
@@ -722,7 +779,7 @@ const Os = switch (builtin.os.tag) {
var event_buffer: [100]posix.Kevent = undefined;
var n = try posix.kevent(w.os.kq_fd, &.{}, &event_buffer, timeout.toTimespec(×pec_buffer));
if (n == 0) return .timeout;
- const reaction_sets = w.os.reaction_sets.items;
+ const reaction_sets = w.os.handles.items(.rs);
var any_dirty = markDirtySteps(gpa, reaction_sets, event_buffer[0..n], false);
timespec_buffer = .{ .sec = 0, .nsec = 0 };
while (n == event_buffer.len) {