Merge branch 'data-man-rusage'

closes #3854

lib/std/c.zig

@@ -109,6 +109,7 @@ pub extern "c" fn setreuid(ruid: c_uint, euid: c_uint) c_int;
 pub extern "c" fn setregid(rgid: c_uint, egid: c_uint) c_int;
 pub extern "c" fn rmdir(path: [*:0]const u8) c_int;
 pub extern "c" fn getenv(name: [*:0]const u8) ?[*:0]u8;
+pub extern "c" fn getrusage(who: c_int, usage: *rusage) c_int;
 pub extern "c" fn sysctl(name: [*]const c_int, namelen: c_uint, oldp: ?*c_void, oldlenp: ?*usize, newp: ?*c_void, newlen: usize) c_int;
 pub extern "c" fn sysctlbyname(name: [*:0]const u8, oldp: ?*c_void, oldlenp: ?*usize, newp: ?*c_void, newlen: usize) c_int;
 pub extern "c" fn sysctlnametomib(name: [*:0]const u8, mibp: ?*c_int, sizep: ?*usize) c_int;

lib/std/os.zig

@@ -3325,3 +3325,14 @@ pub fn memfd_create(name: []const u8, flags: u32) !fd_t {
     const name_t = try toMemFdPath(name);
     return memfd_createC(&name_t, flags);
 }
+
+pub fn getrusage(who: i32) rusage {
+    var result: rusage = undefined;
+    const rc = system.getrusage(who, &result);
+    switch (errno(rc)) {
+        0 => return result,
+        EINVAL => unreachable,
+        EFAULT => unreachable,
+        else => unreachable,
+    }
+}

lib/std/os/bits/linux.zig

@@ -1453,3 +1453,27 @@ pub const MFD_HUGE_512MB = HUGETLB_FLAG_ENCODE_512MB;
 pub const MFD_HUGE_1GB = HUGETLB_FLAG_ENCODE_1GB;
 pub const MFD_HUGE_2GB = HUGETLB_FLAG_ENCODE_2GB;
 pub const MFD_HUGE_16GB = HUGETLB_FLAG_ENCODE_16GB;
+
+pub const RUSAGE_SELF = 0;
+pub const RUSAGE_CHILDREN = -1;
+pub const RUSAGE_THREAD = 1;
+
+pub const rusage = extern struct {
+    utime: timeval,
+    stime: timeval,
+    maxrss: isize,
+    ix_rss: isize,
+    idrss: isize,
+    isrss: isize,
+    minflt: isize,
+    majflt: isize,
+    nswap: isize,
+    inblock: isize,
+    oublock: isize,
+    msgsnd: isize,
+    msgrcv: isize,
+    nsignals: isize,
+    nvcsw: isize,
+    nivcsw: isize,
+    __reserved: [16]isize = [1]isize{0} ** 16,
+};

lib/std/os/linux.zig

@@ -1114,6 +1114,10 @@ pub fn memfd_create(name: [*:0]const u8, flags: u32) usize {
     return syscall2(SYS_memfd_create, @ptrToInt(name), flags);
 }
 
+pub fn getrusage(who: i32, usage: *rusage) usize {
+    return syscall2(SYS_getrusage, @bitCast(usize, @as(isize, who)), @ptrToInt(usage));
+}
+
 test "" {
     if (builtin.os == .linux) {
         _ = @import("linux/test.zig");