libnss: fail early

src/libnss.zig

@@ -201,12 +201,11 @@ export fn _nss_turbo_getgrgid_r(
     errnop: *c_int,
 ) c.enum_nss_status {
     global_init.call();
-    if (global_state) |*state| {
+    var state = &(global_state orelse {
-        return getgrgid_r(state, gid, gr, buffer, buflen, errnop);
-    } else {
         errnop.* = @enumToInt(os.E.AGAIN);
         return c.NSS_STATUS_UNAVAIL;
-    }
+    });
+    return getgrgid_r(state, gid, gr, buffer, buflen, errnop);
 }
 
 fn getgrgid_r(
@@ -228,12 +227,11 @@ fn getgrgid_r(
         },
     };
 
-    const got_cgroup = cgroup orelse {
+    gr.* = cgroup orelse {
         errnop.* = @enumToInt(os.E.NOENT);
         return c.NSS_STATUS_NOTFOUND;
     };
 
-    gr.* = got_cgroup;
     return c.NSS_STATUS_SUCCESS;
 }
 
@@ -245,12 +243,11 @@ export fn _nss_turbo_getgrnam_r(
     errnop: *c_int,
 ) c.enum_nss_status {
     global_init.call();
-    if (global_state) |*state| {
+    var state = &(global_state orelse {
-        return getgrnam_r(state, name, group, buffer, buflen, errnop);
-    } else {
         errnop.* = @enumToInt(os.E.AGAIN);
         return c.NSS_STATUS_UNAVAIL;
-    }
+    });
+    return getgrnam_r(state, name, group, buffer, buflen, errnop);
 }
 
 fn getgrnam_r(
@@ -281,10 +278,8 @@ fn getgrnam_r(
 
 export fn _nss_turbo_setpwent(_: c_int) c.enum_nss_status {
     global_init.call();
-    if (global_state) |*state|
+    var state = &(global_state orelse return c.NSS_STATUS_UNAVAIL);
-        return setpwent(state)
+    return setpwent(state);
-    else
-        return c.NSS_STATUS_UNAVAIL;
 }
 
 fn setpwent(state: *State) c.enum_nss_status {
@@ -302,10 +297,8 @@ fn setpwent(state: *State) c.enum_nss_status {
 
 export fn _nss_turbo_endpwent() c.enum_nss_status {
     global_init.call();
-    if (global_state) |*state|
+    var state = &(global_state orelse return c.NSS_STATUS_UNAVAIL);
-        return endpwent(state)
+    return endpwent(state);
-    else
-        return c.NSS_STATUS_UNAVAIL;
 }
 
 fn endpwent(state: *State) c.enum_nss_status {
@@ -317,10 +310,8 @@ fn endpwent(state: *State) c.enum_nss_status {
 
 export fn _nss_turbo_setgrent(_: c_int) c.enum_nss_status {
     global_init.call();
-    if (global_state) |*state|
+    var state = &(global_state orelse return c.NSS_STATUS_UNAVAIL);
-        return setgrent(state)
+    return setgrent(state);
-    else
-        return c.NSS_STATUS_UNAVAIL;
 }
 
 fn setgrent(state: *State) c.enum_nss_status {
@@ -335,10 +326,8 @@ fn setgrent(state: *State) c.enum_nss_status {
 
 export fn _nss_turbo_endgrent() c.enum_nss_status {
     global_init.call();
-    if (global_state) |*state|
+    var state = &(global_state orelse return c.NSS_STATUS_UNAVAIL);
-        return endgrent(state)
+    return endgrent(state);
-    else
-        return c.NSS_STATUS_UNAVAIL;
 }
 
 fn endgrent(state: *State) c.enum_nss_status {
@@ -355,12 +344,11 @@ export fn _nss_turbo_getgrent_r(
     errnop: *c_int,
 ) c.enum_nss_status {
     global_init.call();
-    if (global_state) |*state| {
+    var state = &(global_state orelse {
-        return getgrent_r(state, result, buffer, buflen, errnop);
-    } else {
         errnop.* = @enumToInt(os.E.AGAIN);
         return c.NSS_STATUS_UNAVAIL;
-    }
+    });
+    return getgrent_r(state, result, buffer, buflen, errnop);
 }
 
 fn getgrent_r(
@@ -373,31 +361,31 @@ fn getgrent_r(
     state.getgrent_iterator_mu.lock();
     defer state.getgrent_iterator_mu.unlock();
 
-    if (state.getgrent_iterator) |*it| {
+    var it = &(state.getgrent_iterator orelse {
-        const group = it.next() orelse {
-            errnop.* = 0;
-            return c.NSS_STATUS_NOTFOUND;
-        };
-
-        const cgroup1 = if (state.omit_members)
-            DB.packCGroupNoMembers(&group, buffer[0..buflen])
-        else
-            state.file.db.packCGroup(&group, buffer[0..buflen]);
-
-        if (cgroup1) |cgroup| {
-            result.* = cgroup;
-            return c.NSS_STATUS_SUCCESS;
-        } else |err| switch (err) {
-            error.BufferTooSmall => {
-                it.rollback();
-                errnop.* = @enumToInt(os.E.RANGE);
-                return c.NSS_STATUS_TRYAGAIN;
-            },
-        }
-    } else {
         // logic from _nss_systemd_getgrent_r
         errnop.* = @enumToInt(os.E.HOSTDOWN);
         return c.NSS_STATUS_UNAVAIL;
+    });
+
+    const group = it.next() orelse {
+        errnop.* = 0;
+        return c.NSS_STATUS_NOTFOUND;
+    };
+
+    const cgroup1 = if (state.omit_members)
+        DB.packCGroupNoMembers(&group, buffer[0..buflen])
+    else
+        state.file.db.packCGroup(&group, buffer[0..buflen]);
+
+    if (cgroup1) |cgroup| {
+        result.* = cgroup;
+        return c.NSS_STATUS_SUCCESS;
+    } else |err| switch (err) {
+        error.BufferTooSmall => {
+            it.rollback();
+            errnop.* = @enumToInt(os.E.RANGE);
+            return c.NSS_STATUS_TRYAGAIN;
+        },
     }
 }
 
@@ -408,12 +396,12 @@ export fn _nss_turbo_getpwent_r(
     errnop: *c_int,
 ) c.enum_nss_status {
     global_init.call();
-    if (global_state) |*state| {
+    var state = &(global_state orelse {
-        return getpwent_r(state, result, buffer, buflen, errnop);
-    } else {
         errnop.* = @enumToInt(os.E.AGAIN);
         return c.NSS_STATUS_UNAVAIL;
-    }
+    });
+
+    return getpwent_r(state, result, buffer, buflen, errnop);
 }
 
 fn getpwent_r(
@@ -426,28 +414,28 @@ fn getpwent_r(
     state.getpwent_iterator_mu.lock();
     defer state.getpwent_iterator_mu.unlock();
 
-    if (state.getpwent_iterator) |*it| {
+    var it = &(state.getpwent_iterator orelse {
-        const user = it.next() orelse {
-            errnop.* = 0;
-            return c.NSS_STATUS_NOTFOUND;
-        };
-
-        const buf = buffer[0..buflen];
-        const cuser = state.file.db.writeUser(user, buf) catch |err| switch (err) {
-            error.BufferTooSmall => {
-                it.rollback();
-                errnop.* = @enumToInt(os.E.RANGE);
-                return c.NSS_STATUS_TRYAGAIN;
-            },
-        };
-
-        result.* = cuser;
-        return c.NSS_STATUS_SUCCESS;
-    } else {
         // logic from _nss_systemd_getgrent_r
         errnop.* = @enumToInt(os.E.HOSTDOWN);
         return c.NSS_STATUS_UNAVAIL;
-    }
+    });
+
+    const user = it.next() orelse {
+        errnop.* = 0;
+        return c.NSS_STATUS_NOTFOUND;
+    };
+
+    const buf = buffer[0..buflen];
+    const cuser = state.file.db.writeUser(user, buf) catch |err| switch (err) {
+        error.BufferTooSmall => {
+            it.rollback();
+            errnop.* = @enumToInt(os.E.RANGE);
+            return c.NSS_STATUS_TRYAGAIN;
+        },
+    };
+
+    result.* = cuser;
+    return c.NSS_STATUS_SUCCESS;
 }
 
 export fn _nss_turbo_initgroups_dyn(
@@ -460,12 +448,11 @@ export fn _nss_turbo_initgroups_dyn(
     errnop: *c_int,
 ) c.enum_nss_status {
     global_init.call();
-    if (global_state) |*state| {
+    var state = &(global_state orelse {
-        return initgroups_dyn(state, user_name, gid, start, size, groupsp, limit, errnop);
-    } else {
         errnop.* = @enumToInt(os.E.AGAIN);
         return c.NSS_STATUS_UNAVAIL;
-    }
+    });
+    return initgroups_dyn(state, user_name, gid, start, size, groupsp, limit, errnop);
 }
 
 fn initgroups_dyn(
@@ -536,12 +523,11 @@ fn initgroups_dyn(
 
 fn getDBErrno(errnop: *c_int) ?*const DB {
     global_init.call();
-    if (global_state) |*state| {
+    var state = &(global_state orelse {
-        return &state.file.db;
-    } else {
         errnop.* = @enumToInt(os.E.AGAIN);
         return null;
-    }
+    });
+    return &state.file.db;
 }
 
 // isId tells if this command is "id". Reads the cmdline
@@ -718,7 +704,7 @@ test "libnss isId" {
         defer os.close(fd);
         _ = try os.write(fd, tt.cmdline);
         try os.lseek_SET(fd, 0);
-        const got = isId(fd);
+
-        try testing.expectEqual(tt.want, got);
+        try testing.expectEqual(tt.want, isId(fd));
     }
 }