| author |  LeRoyce Pearson <leroycepearson@geemili.xyz> 2020-03-08 20:57:47-06:00 |
| committer | LeRoyce Pearson <leroycepearson@geemili.xyz> 2020-03-14 10:12:46-06:00 |
| log | 9af0590a282e3cf1aa209f4de35402a50effe7a8 |
| tree | 648fa372cebcbb2b612b9e170a8fdebf28ab2a65 |
| parent | 3110060351f98ea8de65809379e1bcd9607fb1cb |
Add fnctlFlock system call, use it to lock files
5 files changed, 46 insertions(+), 0 deletions(-)
lib/std/fs.zig+14
| ... | ... | @@ -677,6 +677,20 @@ pub const Dir = struct { |
| 677 | 677 | try std.event.Loop.instance.?.openatZ(self.fd, sub_path, os_flags, 0) |
| 678 | 678 | else |
| 679 | 679 | try os.openatC(self.fd, sub_path, os_flags, 0); |
| 680 | ||
| 681 | var locked = false; | |
| 682 | if (flags.lock) { | |
| 683 | // TODO: integrate async I/O | |
| 684 | try os.fcntlFlockBlocking(fd, &os.flock{ | |
| 685 | .lock_type = if (flags.write) os.F_WRLCK else os.F_RDLCK, | |
| 686 | .whence = os.SEEK_SET, | |
| 687 | .start = 0, | |
| 688 | .len = 0, | |
| 689 | .pid = 0, | |
| 690 | }); | |
| 691 | locked = true; | |
| 692 | } | |
| 693 | ||
| 680 | 694 | return File{ |
| 681 | 695 | .handle = fd, |
| 682 | 696 | .io_mode = .blocking, |
lib/std/os.zig+8
| ... | ... | @@ -1140,6 +1140,14 @@ pub fn freeNullDelimitedEnvMap(allocator: *mem.Allocator, envp_buf: []?[*:0]u8) |
| 1140 | 1140 | allocator.free(envp_buf); |
| 1141 | 1141 | } |
| 1142 | 1142 | |
| 1143 | /// Attempts to get lock the file, blocking if the file is locked. | |
| 1144 | pub fn fcntlFlockBlocking(fd: fd_t, flock_p: *flock) OpenError!void { | |
| 1145 | const rc = system.fcntlFlock(fd, F_SETLKW, flock_p); | |
| 1146 | if (rc < 0) { | |
| 1147 | std.debug.panic("fcntl error: {}\n", .{rc}); | |
| 1148 | } | |
| 1149 | } | |
| 1150 | ||
| 1143 | 1151 | /// Get an environment variable. |
| 1144 | 1152 | /// See also `getenvZ`. |
| 1145 | 1153 | pub fn getenv(key: []const u8) ?[]const u8 { |
lib/std/os/bits/linux/i386.zig+8
| ... | ... | @@ -488,6 +488,14 @@ pub const MMAP2_UNIT = 4096; |
| 488 | 488 | pub const VDSO_CGT_SYM = "__vdso_clock_gettime"; |
| 489 | 489 | pub const VDSO_CGT_VER = "LINUX_2.6"; |
| 490 | 490 | |
| 491 | pub const flock = extern struct { | |
| 492 | lock_type: i16, | |
| 493 | whence: i16, | |
| 494 | start: off_t, | |
| 495 | len: off_t, | |
| 496 | pid: pid_t, | |
| 497 | }; | |
| 498 | ||
| 491 | 499 | pub const msghdr = extern struct { |
| 492 | 500 | msg_name: ?*sockaddr, |
| 493 | 501 | msg_namelen: socklen_t, |
lib/std/os/bits/linux/x86_64.zig+12
| ... | ... | @@ -456,6 +456,18 @@ pub const REG_TRAPNO = 20; |
| 456 | 456 | pub const REG_OLDMASK = 21; |
| 457 | 457 | pub const REG_CR2 = 22; |
| 458 | 458 | |
| 459 | pub const F_RDLCK = 0; | |
| 460 | pub const F_WRLCK = 1; | |
| 461 | pub const F_UNLCK = 2; | |
| 462 | ||
| 463 | pub const flock = extern struct { | |
| 464 | lock_type: i16, | |
| 465 | whence: i16, | |
| 466 | start: off_t, | |
| 467 | len: off_t, | |
| 468 | pid: pid_t, | |
| 469 | }; | |
| 470 | ||
| 459 | 471 | pub const msghdr = extern struct { |
| 460 | 472 | msg_name: ?*sockaddr, |
| 461 | 473 | msg_namelen: socklen_t, |
lib/std/os/linux.zig+4
| ... | ... | @@ -219,6 +219,10 @@ pub fn mmap(address: ?[*]u8, length: usize, prot: usize, flags: u32, fd: i32, of |
| 219 | 219 | } |
| 220 | 220 | } |
| 221 | 221 | |
| 222 | pub fn fcntlFlock(fd: fd_t, cmd: i32, flock_p: *flock) usize { | |
| 223 | return syscall3(SYS_fcntl, @bitCast(usize, @as(isize, fd)), @bitCast(usize, @as(isize, cmd)), @ptrToInt(flock_p)); | |
| 224 | } | |
| 225 | ||
| 222 | 226 | pub fn mprotect(address: [*]const u8, length: usize, protection: usize) usize { |
| 223 | 227 | return syscall3(SYS_mprotect, @ptrToInt(address), length, protection); |
| 224 | 228 | } |