zig/lib/std/c/parse.zig

1431 lines
52 KiB
Zig

const std = @import("std");
const mem = std.mem;
const assert = std.debug.assert;
const Allocator = std.mem.Allocator;
const ast = std.c.ast;
const Node = ast.Node;
const Type = ast.Type;
const Tree = ast.Tree;
const TokenIndex = ast.TokenIndex;
const Token = std.c.Token;
const TokenIterator = ast.Tree.TokenList.Iterator;
pub const Error = error{ParseError} || Allocator.Error;
pub const Options = struct {
// /// Keep simple macros unexpanded and add the definitions to the ast
// retain_macros: bool = false,
/// Warning or error
warn_as_err: union(enum) {
/// All warnings are warnings
None,
/// Some warnings are errors
Some: []@TagType(ast.Error),
/// All warnings are errors
All,
} = .All,
};
/// Result should be freed with tree.deinit() when there are
/// no more references to any of the tokens or nodes.
pub fn parse(allocator: *Allocator, source: []const u8, options: Options) !*Tree {
const tree = blk: {
// This block looks unnecessary, but is a "foot-shield" to prevent the SegmentedLists
// from being initialized with a pointer to this `arena`, which is created on
// the stack. Following code should instead refer to `&tree.arena_allocator`, a
// pointer to data which lives safely on the heap and will outlive `parse`.
var arena = std.heap.ArenaAllocator.init(allocator);
errdefer arena.deinit();
const tree = try arena.allocator.create(ast.Tree);
tree.* = .{
.root_node = undefined,
.arena_allocator = arena,
.tokens = undefined,
.sources = undefined,
};
break :blk tree;
};
errdefer tree.deinit();
const arena = &tree.arena_allocator.allocator;
tree.tokens = ast.Tree.TokenList.init(arena);
tree.sources = ast.Tree.SourceList.init(arena);
var tokenizer = std.zig.Tokenizer.init(source);
while (true) {
const tree_token = try tree.tokens.addOne();
tree_token.* = tokenizer.next();
if (tree_token.id == .Eof) break;
}
// TODO preprocess here
var it = tree.tokens.iterator(0);
while (true) {
const tok = it.peek().?.id;
switch (id) {
.LineComment,
.MultiLineComment,
=> {
_ = it.next();
},
else => break,
}
}
var parse_arena = std.heap.ArenaAllocator.init(allocator);
defer parse_arena.deinit();
var parser = Parser{
.scopes = Parser.SymbolList.init(allocator),
.arena = &parse_arena.allocator,
.it = &it,
.tree = tree,
.options = options,
};
defer parser.symbols.deinit();
tree.root_node = try parser.root();
return tree;
}
const Parser = struct {
arena: *Allocator,
it: *TokenIterator,
tree: *Tree,
arena: *Allocator,
scopes: ScopeList,
options: Options,
const ScopeList = std.SegmentedLists(Scope);
const SymbolList = std.SegmentedLists(Symbol);
const Scope = struct {
kind: ScopeKind,
syms: SymbolList,
};
const Symbol = struct {
name: []const u8,
ty: *Type,
};
const ScopeKind = enum {
Block,
Loop,
Root,
Switch,
};
fn pushScope(parser: *Parser, kind: ScopeKind) !void {
const new = try parser.scopes.addOne();
new.* = .{
.kind = kind,
.syms = SymbolList.init(parser.arena),
};
}
fn popScope(parser: *Parser, len: usize) void {
_ = parser.scopes.pop();
}
fn getSymbol(parser: *Parser, tok: TokenIndex) ?*Symbol {
const name = parser.tree.tokenSlice(tok);
var scope_it = parser.scopes.iterator(parser.scopes.len);
while (scope_it.prev()) |scope| {
var sym_it = scope.syms.iterator(scope.syms.len);
while (sym_it.prev()) |sym| {
if (mem.eql(u8, sym.name, name)) {
return sym;
}
}
}
return null;
}
fn declareSymbol(parser: *Parser, type_spec: Node.TypeSpec, dr: *Node.Declarator) Error!void {
return; // TODO
}
/// Root <- ExternalDeclaration* eof
fn root(parser: *Parser) Allocator.Error!*Node.Root {
try parser.pushScope(.Root);
defer parser.popScope();
const node = try parser.arena.create(Node.Root);
node.* = .{
.decls = Node.Root.DeclList.init(parser.arena),
.eof = undefined,
};
while (parser.externalDeclarations() catch |e| switch (e) {
error.OutOfMemory => return error.OutOfMemory,
error.ParseError => return node,
}) |decl| {
try node.decls.push(decl);
}
node.eof = parser.eatToken(.Eof) orelse return node;
return node;
}
/// ExternalDeclaration
/// <- DeclSpec Declarator OldStyleDecl* CompoundStmt
/// / Declaration
/// OldStyleDecl <- DeclSpec Declarator (COMMA Declarator)* SEMICOLON
fn externalDeclarations(parser: *Parser) !?*Node {
return parser.declarationExtra(false);
}
/// Declaration
/// <- DeclSpec DeclInit SEMICOLON
/// / StaticAssert
/// DeclInit <- Declarator (EQUAL Initializer)? (COMMA Declarator (EQUAL Initializer)?)*
fn declaration(parser: *Parser) !?*Node {
return parser.declarationExtra(true);
}
fn declarationExtra(parser: *Parser, local: bool) !?*Node {
if (try parser.staticAssert()) |decl| return decl;
const begin = parser.it.index + 1;
var ds = Node.DeclSpec{};
const got_ds = try parser.declSpec(&ds);
if (local and !got_ds) {
// not a declaration
return null;
}
switch (ds.storage_class) {
.Auto, .Register => |tok| return parser.err(.{
.InvalidStorageClass = .{ .token = tok },
}),
.Typedef => {
const node = try parser.arena.create(Node.Typedef);
node.* = .{
.decl_spec = ds,
.declarators = Node.Typedef.DeclaratorList.init(parser.arena),
.semicolon = undefined,
};
while (true) {
const dr = @fieldParentPtr(Node.Declarator, "base", (try parser.declarator(.Must)) orelse return parser.err(.{
.ExpectedDeclarator = .{ .token = parser.it.index },
}));
try parser.declareSymbol(ds.type_spec, dr);
try node.declarators.push(&dr.base);
if (parser.eatToken(.Comma)) |_| {} else break;
}
return &node.base;
},
else => {},
}
var first_dr = try parser.declarator(.Must);
if (first_dr != null and declaratorIsFunction(first_dr.?)) {
// TODO typedeffed fn proto-only
const dr = @fieldParentPtr(Node.Declarator, "base", first_dr.?);
try parser.declareSymbol(ds.type_spec, dr);
var old_decls = Node.FnDecl.OldDeclList.init(parser.arena);
const body = if (parser.eatToken(.Semicolon)) |_|
null
else blk: {
if (local) {
// TODO nested function warning
}
// TODO first_dr.is_old
// while (true) {
// var old_ds = Node.DeclSpec{};
// if (!(try parser.declSpec(&old_ds))) {
// // not old decl
// break;
// }
// var old_dr = (try parser.declarator(.Must));
// // if (old_dr == null)
// // try parser.err(.{
// // .NoParamName = .{ .token = parser.it.index },
// // });
// // try old_decls.push(decl);
// }
const body_node = (try parser.compoundStmt()) orelse return parser.err(.{
.ExpectedFnBody = .{ .token = parser.it.index },
});
break :blk @fieldParentPtr(Node.CompoundStmt, "base", body_node);
};
const node = try parser.arena.create(Node.FnDecl);
node.* = .{
.decl_spec = ds,
.declarator = dr,
.old_decls = old_decls,
.body = body,
};
return &node.base;
} else {
switch (ds.fn_spec) {
.Inline, .Noreturn => |tok| return parser.err(.{
.FnSpecOnNonFn = .{ .token = tok },
}),
else => {},
}
// TODO threadlocal without static or extern on local variable
const node = try parser.arena.create(Node.VarDecl);
node.* = .{
.decl_spec = ds,
.initializers = Node.VarDecl.Initializers.init(parser.arena),
.semicolon = undefined,
};
if (first_dr == null) {
node.semicolon = try parser.expectToken(.Semicolon);
const ok = switch (ds.type_spec.spec) {
.Enum => |e| e.name != null,
.Record => |r| r.name != null,
else => false,
};
const q = ds.type_spec.qual;
if (!ok)
try parser.warn(.{
.NothingDeclared = .{ .token = begin },
})
else if (q.@"const" orelse q.atomic orelse q.@"volatile" orelse q.restrict) |tok|
try parser.warn(.{
.QualifierIgnored = .{ .token = tok },
});
return &node.base;
}
var dr = @fieldParentPtr(Node.Declarator, "base", first_dr.?);
while (true) {
try parser.declareSymbol(ds.type_spec, dr);
if (parser.eatToken(.Equal)) |tok| {
try node.initializers.push((try parser.initializer(dr)) orelse return parser.err(.{
.ExpectedInitializer = .{ .token = parser.it.index },
}));
} else
try node.initializers.push(&dr.base);
if (parser.eatToken(.Comma) != null) break;
dr = @fieldParentPtr(Node.Declarator, "base", (try parser.declarator(.Must)) orelse return parser.err(.{
.ExpectedDeclarator = .{ .token = parser.it.index },
}));
}
node.semicolon = try parser.expectToken(.Semicolon);
return &node.base;
}
}
fn declaratorIsFunction(node: *Node) bool {
if (node.id != .Declarator) return false;
assert(node.id == .Declarator);
const dr = @fieldParentPtr(Node.Declarator, "base", node);
if (dr.suffix != .Fn) return false;
switch (dr.prefix) {
.None, .Identifer => return true,
.Complex => |inner| {
var inner_node = inner.inner;
while (true) {
if (inner_node.id != .Declarator) return false;
assert(inner_node.id == .Declarator);
const inner_dr = @fieldParentPtr(Node.Declarator, "base", inner_node);
if (inner_dr.pointer != null) return false;
switch (inner_dr.prefix) {
.None, .Identifer => return true,
.Complex => |c| inner_node = c.inner,
}
}
},
}
}
/// StaticAssert <- Keyword_static_assert LPAREN ConstExpr COMMA STRINGLITERAL RPAREN SEMICOLON
fn staticAssert(parser: *Parser) !?*Node {
const tok = parser.eatToken(.Keyword_static_assert) orelse return null;
_ = try parser.expectToken(.LParen);
const const_expr = (try parser.constExpr()) orelse parser.err(.{
.ExpectedExpr = .{ .token = parser.it.index },
});
_ = try parser.expectToken(.Comma);
const str = try parser.expectToken(.StringLiteral);
_ = try parser.expectToken(.RParen);
const node = try parser.arena.create(Node.StaticAssert);
node.* = .{
.assert = tok,
.expr = const_expr,
.semicolon = try parser.expectToken(.Semicolon),
};
return &node.base;
}
/// DeclSpec <- (StorageClassSpec / TypeSpec / FnSpec / AlignSpec)*
/// returns true if any tokens were consumed
fn declSpec(parser: *Parser, ds: *Node.DeclSpec) !bool {
var got = false;
while ((try parser.storageClassSpec(ds)) or (try parser.typeSpec(&ds.type_spec)) or (try parser.fnSpec(ds)) or (try parser.alignSpec(ds))) {
got = true;
}
return got;
}
/// StorageClassSpec
/// <- Keyword_typedef / Keyword_extern / Keyword_static / Keyword_thread_local / Keyword_auto / Keyword_register
fn storageClassSpec(parser: *Parser, ds: *Node.DeclSpec) !bool {
blk: {
if (parser.eatToken(.Keyword_typedef)) |tok| {
if (ds.storage_class != .None or ds.thread_local != null)
break :blk;
ds.storage_class = .{ .Typedef = tok };
} else if (parser.eatToken(.Keyword_extern)) |tok| {
if (ds.storage_class != .None)
break :blk;
ds.storage_class = .{ .Extern = tok };
} else if (parser.eatToken(.Keyword_static)) |tok| {
if (ds.storage_class != .None)
break :blk;
ds.storage_class = .{ .Static = tok };
} else if (parser.eatToken(.Keyword_thread_local)) |tok| {
switch (ds.storage_class) {
.None, .Extern, .Static => {},
else => break :blk,
}
ds.thread_local = tok;
} else if (parser.eatToken(.Keyword_auto)) |tok| {
if (ds.storage_class != .None or ds.thread_local != null)
break :blk;
ds.storage_class = .{ .Auto = tok };
} else if (parser.eatToken(.Keyword_register)) |tok| {
if (ds.storage_class != .None or ds.thread_local != null)
break :blk;
ds.storage_class = .{ .Register = tok };
} else return false;
return true;
}
try parser.warn(.{
.DuplicateSpecifier = .{ .token = parser.it.index },
});
return true;
}
/// TypeSpec
/// <- Keyword_void / Keyword_char / Keyword_short / Keyword_int / Keyword_long / Keyword_float / Keyword_double
/// / Keyword_signed / Keyword_unsigned / Keyword_bool / Keyword_complex / Keyword_imaginary /
/// / Keyword_atomic LPAREN TypeName RPAREN
/// / EnumSpec
/// / RecordSpec
/// / IDENTIFIER // typedef name
/// / TypeQual
fn typeSpec(parser: *Parser, type_spec: *Node.TypeSpec) !bool {
blk: {
if (parser.eatToken(.Keyword_void)) |tok| {
if (type_spec.spec != .None)
break :blk;
type_spec.spec = .{ .Void = tok };
} else if (parser.eatToken(.Keyword_char)) |tok| {
switch (type_spec.spec) {
.None => {
type_spec.spec = .{
.Char = .{
.char = tok,
},
};
},
.Int => |int| {
if (int.int != null)
break :blk;
type_spec.spec = .{
.Char = .{
.char = tok,
.sign = int.sign,
},
};
},
else => break :blk,
}
} else if (parser.eatToken(.Keyword_short)) |tok| {
switch (type_spec.spec) {
.None => {
type_spec.spec = .{
.Short = .{
.short = tok,
},
};
},
.Int => |int| {
if (int.int != null)
break :blk;
type_spec.spec = .{
.Short = .{
.short = tok,
.sign = int.sign,
},
};
},
else => break :blk,
}
} else if (parser.eatToken(.Keyword_long)) |tok| {
switch (type_spec.spec) {
.None => {
type_spec.spec = .{
.Long = .{
.long = tok,
},
};
},
.Int => |int| {
type_spec.spec = .{
.Long = .{
.long = tok,
.sign = int.sign,
.int = int.int,
},
};
},
.Long => |*long| {
if (long.longlong != null)
break :blk;
long.longlong = tok;
},
.Double => |*double| {
if (double.long != null)
break :blk;
double.long = tok;
},
else => break :blk,
}
} else if (parser.eatToken(.Keyword_int)) |tok| {
switch (type_spec.spec) {
.None => {
type_spec.spec = .{
.Int = .{
.int = tok,
},
};
},
.Short => |*short| {
if (short.int != null)
break :blk;
short.int = tok;
},
.Int => |*int| {
if (int.int != null)
break :blk;
int.int = tok;
},
.Long => |*long| {
if (long.int != null)
break :blk;
long.int = tok;
},
else => break :blk,
}
} else if (parser.eatToken(.Keyword_signed) orelse parser.eatToken(.Keyword_unsigned)) |tok| {
switch (type_spec.spec) {
.None => {
type_spec.spec = .{
.Int = .{
.sign = tok,
},
};
},
.Char => |*char| {
if (char.sign != null)
break :blk;
char.sign = tok;
},
.Short => |*short| {
if (short.sign != null)
break :blk;
short.sign = tok;
},
.Int => |*int| {
if (int.sign != null)
break :blk;
int.sign = tok;
},
.Long => |*long| {
if (long.sign != null)
break :blk;
long.sign = tok;
},
else => break :blk,
}
} else if (parser.eatToken(.Keyword_float)) |tok| {
if (type_spec.spec != .None)
break :blk;
type_spec.spec = .{
.Float = .{
.float = tok,
},
};
} else if (parser.eatToken(.Keyword_double)) |tok| {
if (type_spec.spec != .None)
break :blk;
type_spec.spec = .{
.Double = .{
.double = tok,
},
};
} else if (parser.eatToken(.Keyword_complex)) |tok| {
switch (type_spec.spec) {
.None => {
type_spec.spec = .{
.Double = .{
.complex = tok,
.double = null,
},
};
},
.Float => |*float| {
if (float.complex != null)
break :blk;
float.complex = tok;
},
.Double => |*double| {
if (double.complex != null)
break :blk;
double.complex = tok;
},
else => break :blk,
}
} else if (parser.eatToken(.Keyword_bool)) |tok| {
if (type_spec.spec != .None)
break :blk;
type_spec.spec = .{ .Bool = tok };
} else if (parser.eatToken(.Keyword_atomic)) |tok| {
// might be _Atomic qualifier
if (parser.eatToken(.LParen)) |_| {
if (type_spec.spec != .None)
break :blk;
const name = (try parser.typeName()) orelse return parser.err(.{
.ExpectedTypeName = .{ .token = parser.it.index },
});
type_spec.spec.Atomic = .{
.atomic = tok,
.typename = name,
.rparen = try parser.expectToken(.RParen),
};
} else {
parser.putBackToken(tok);
}
} else if (parser.eatToken(.Keyword_enum)) |tok| {
if (type_spec.spec != .None)
break :blk;
type_spec.spec.Enum = try parser.enumSpec(tok);
} else if (parser.eatToken(.Keyword_union) orelse parser.eatToken(.Keyword_struct)) |tok| {
if (type_spec.spec != .None)
break :blk;
type_spec.spec.Record = try parser.recordSpec(tok);
} else if (parser.eatToken(.Identifier)) |tok| {
const ty = parser.getSymbol(tok) orelse {
parser.putBackToken(tok);
return false;
};
switch (ty.id) {
.Enum => |e| blk: {
if (e.name) |some|
if (!parser.tree.tokenEql(some, tok))
break :blk;
return parser.err(.{
.MustUseKwToRefer = .{ .kw = e.tok, .name = tok },
});
},
.Record => |r| blk: {
if (r.name) |some|
if (!parser.tree.tokenEql(some, tok))
break :blk;
return parser.err(.{
.MustUseKwToRefer = .{
.kw = r.tok,
.name = tok,
},
});
},
.Typedef => {
type_spec.spec = .{
.Typedef = .{
.sym = tok,
.sym_type = ty,
},
};
return true;
},
else => {},
}
parser.putBackToken(tok);
return false;
}
return parser.typeQual(&type_spec.qual);
}
return parser.err(.{
.InvalidTypeSpecifier = .{
.token = parser.it.index,
.type_spec = type_spec,
},
});
}
/// TypeQual <- Keyword_const / Keyword_restrict / Keyword_volatile / Keyword_atomic
fn typeQual(parser: *Parser, qual: *Node.TypeQual) !bool {
blk: {
if (parser.eatToken(.Keyword_const)) |tok| {
if (qual.@"const" != null)
break :blk;
qual.@"const" = tok;
} else if (parser.eatToken(.Keyword_restrict)) |tok| {
if (qual.atomic != null)
break :blk;
qual.atomic = tok;
} else if (parser.eatToken(.Keyword_volatile)) |tok| {
if (qual.@"volatile" != null)
break :blk;
qual.@"volatile" = tok;
} else if (parser.eatToken(.Keyword_atomic)) |tok| {
if (qual.atomic != null)
break :blk;
qual.atomic = tok;
} else return false;
return true;
}
try parser.warn(.{
.DuplicateQualifier = .{ .token = parser.it.index },
});
return true;
}
/// FnSpec <- Keyword_inline / Keyword_noreturn
fn fnSpec(parser: *Parser, ds: *Node.DeclSpec) !bool {
blk: {
if (parser.eatToken(.Keyword_inline)) |tok| {
if (ds.fn_spec != .None)
break :blk;
ds.fn_spec = .{ .Inline = tok };
} else if (parser.eatToken(.Keyword_noreturn)) |tok| {
if (ds.fn_spec != .None)
break :blk;
ds.fn_spec = .{ .Noreturn = tok };
} else return false;
return true;
}
try parser.warn(.{
.DuplicateSpecifier = .{ .token = parser.it.index },
});
return true;
}
/// AlignSpec <- Keyword_alignas LPAREN (TypeName / ConstExpr) RPAREN
fn alignSpec(parser: *Parser, ds: *Node.DeclSpec) !bool {
if (parser.eatToken(.Keyword_alignas)) |tok| {
_ = try parser.expectToken(.LParen);
const node = (try parser.typeName()) orelse (try parser.constExpr()) orelse parser.err(.{
.ExpectedExpr = .{ .token = parser.it.index },
});
if (ds.align_spec != null) {
try parser.warn(.{
.DuplicateSpecifier = .{ .token = parser.it.index },
});
}
ds.align_spec = .{
.alignas = tok,
.expr = node,
.rparen = try parser.expectToken(.RParen),
};
return true;
}
return false;
}
/// EnumSpec <- Keyword_enum IDENTIFIER? (LBRACE EnumField RBRACE)?
fn enumSpec(parser: *Parser, tok: TokenIndex) !*Node.EnumType {
const node = try parser.arena.create(Node.EnumType);
const name = parser.eatToken(.Identifier);
node.* = .{
.tok = tok,
.name = name,
.body = null,
};
const ty = try parser.arena.create(Type);
ty.* = .{
.id = .{
.Enum = node,
},
};
if (name) |some|
try parser.symbols.append(.{
.name = parser.tree.tokenSlice(some),
.ty = ty,
});
if (parser.eatToken(.LBrace)) |lbrace| {
var fields = Node.EnumType.FieldList.init(parser.arena);
try fields.push((try parser.enumField()) orelse return parser.err(.{
.ExpectedEnumField = .{ .token = parser.it.index },
}));
while (parser.eatToken(.Comma)) |_| {
try fields.push((try parser.enumField()) orelse break);
}
node.body = .{
.lbrace = lbrace,
.fields = fields,
.rbrace = try parser.expectToken(.RBrace),
};
}
return node;
}
/// EnumField <- IDENTIFIER (EQUAL ConstExpr)? (COMMA EnumField) COMMA?
fn enumField(parser: *Parser) !?*Node {
const name = parser.eatToken(.Identifier) orelse return null;
const node = try parser.arena.create(Node.EnumField);
node.* = .{
.name = name,
.value = null,
};
if (parser.eatToken(.Equal)) |eq| {
node.value = (try parser.constExpr()) orelse parser.err(.{
.ExpectedExpr = .{ .token = parser.it.index },
});
}
return &node.base;
}
/// RecordSpec <- (Keyword_struct / Keyword_union) IDENTIFIER? (LBRACE RecordField+ RBRACE)?
fn recordSpec(parser: *Parser, tok: TokenIndex) !*Node.RecordType {
const node = try parser.arena.create(Node.RecordType);
const name = parser.eatToken(.Identifier);
const is_struct = parser.tree.tokenSlice(tok)[0] == 's';
node.* = .{
.tok = tok,
.kind = if (is_struct) .Struct else .Union,
.name = name,
.body = null,
};
const ty = try parser.arena.create(Type);
ty.* = .{
.id = .{
.Record = node,
},
};
if (name) |some|
try parser.symbols.append(.{
.name = parser.tree.tokenSlice(some),
.ty = ty,
});
if (parser.eatToken(.LBrace)) |lbrace| {
try parser.pushScope(.Block);
defer parser.popScope();
var fields = Node.RecordType.FieldList.init(parser.arena);
while (true) {
if (parser.eatToken(.RBrace)) |rbrace| {
node.body = .{
.lbrace = lbrace,
.fields = fields,
.rbrace = rbrace,
};
break;
}
try fields.push(try parser.recordField());
}
}
return node;
}
/// RecordField
/// <- TypeSpec* (RecordDeclarator (COMMA RecordDeclarator))? SEMICOLON
/// \ StaticAssert
fn recordField(parser: *Parser) Error!*Node {
if (try parser.staticAssert()) |decl| return decl;
var got = false;
var type_spec = Node.TypeSpec{};
while (try parser.typeSpec(&type_spec)) got = true;
if (!got)
return parser.err(.{
.ExpectedType = .{ .token = parser.it.index },
});
const node = try parser.arena.create(Node.RecordField);
node.* = .{
.type_spec = type_spec,
.declarators = Node.RecordField.DeclaratorList.init(parser.arena),
.semicolon = undefined,
};
while (true) {
const rdr = try parser.recordDeclarator();
try parser.declareSymbol(type_spec, rdr.declarator);
try node.declarators.push(&rdr.base);
if (parser.eatToken(.Comma)) |_| {} else break;
}
node.semicolon = try parser.expectToken(.Semicolon);
return &node.base;
}
/// TypeName <- TypeSpec* AbstractDeclarator?
fn typeName(parser: *Parser) Error!?*Node {
@panic("TODO");
}
/// RecordDeclarator <- Declarator? (COLON ConstExpr)?
fn recordDeclarator(parser: *Parser) Error!*Node.RecordDeclarator {
@panic("TODO");
}
/// Pointer <- ASTERISK TypeQual* Pointer?
fn pointer(parser: *Parser) Error!?*Node.Pointer {
const asterisk = parser.eatToken(.Asterisk) orelse return null;
const node = try parser.arena.create(Node.Pointer);
node.* = .{
.asterisk = asterisk,
.qual = .{},
.pointer = null,
};
while (try parser.typeQual(&node.qual)) {}
node.pointer = try parser.pointer();
return node;
}
const Named = enum {
Must,
Allowed,
Forbidden,
};
/// Declarator <- Pointer? DeclaratorSuffix
/// DeclaratorPrefix
/// <- IDENTIFIER // if named != .Forbidden
/// / LPAREN Declarator RPAREN
/// / (none) // if named != .Must
/// DeclaratorSuffix
/// <- DeclaratorPrefix (LBRACKET ArrayDeclarator? RBRACKET)*
/// / DeclaratorPrefix LPAREN (ParamDecl (COMMA ParamDecl)* (COMMA ELLIPSIS)?)? RPAREN
fn declarator(parser: *Parser, named: Named) Error!?*Node {
const ptr = try parser.pointer();
var node: *Node.Declarator = undefined;
var inner_fn = false;
// TODO sizof(int (int))
// prefix
if (parser.eatToken(.LParen)) |lparen| {
const inner = (try parser.declarator(named)) orelse return parser.err(.{
.ExpectedDeclarator = .{ .token = lparen + 1 },
});
inner_fn = declaratorIsFunction(inner);
node = try parser.arena.create(Node.Declarator);
node.* = .{
.pointer = ptr,
.prefix = .{
.Complex = .{
.lparen = lparen,
.inner = inner,
.rparen = try parser.expectToken(.RParen),
},
},
.suffix = .None,
};
} else if (named != .Forbidden) {
if (parser.eatToken(.Identifier)) |tok| {
node = try parser.arena.create(Node.Declarator);
node.* = .{
.pointer = ptr,
.prefix = .{ .Identifer = tok },
.suffix = .None,
};
} else if (named == .Must) {
return parser.err(.{
.ExpectedToken = .{ .token = parser.it.index, .expected_id = .Identifier },
});
} else {
if (ptr) |some|
return &some.base;
return null;
}
} else {
node = try parser.arena.create(Node.Declarator);
node.* = .{
.pointer = ptr,
.prefix = .None,
.suffix = .None,
};
}
// suffix
if (parser.eatToken(.LParen)) |lparen| {
if (inner_fn)
return parser.err(.{
.InvalidDeclarator = .{ .token = lparen },
});
node.suffix = .{
.Fn = .{
.lparen = lparen,
.params = Node.Declarator.Params.init(parser.arena),
.rparen = undefined,
},
};
try parser.paramDecl(node);
node.suffix.Fn.rparen = try parser.expectToken(.RParen);
} else if (parser.eatToken(.LBracket)) |tok| {
if (inner_fn)
return parser.err(.{
.InvalidDeclarator = .{ .token = tok },
});
node.suffix = .{ .Array = Node.Declarator.Arrays.init(parser.arena) };
var lbrace = tok;
while (true) {
try node.suffix.Array.push(try parser.arrayDeclarator(lbrace));
if (parser.eatToken(.LBracket)) |t| lbrace = t else break;
}
}
if (parser.eatToken(.LParen) orelse parser.eatToken(.LBracket)) |tok|
return parser.err(.{
.InvalidDeclarator = .{ .token = tok },
});
return &node.base;
}
/// ArrayDeclarator
/// <- ASTERISK
/// / Keyword_static TypeQual* AssignmentExpr
/// / TypeQual+ (ASTERISK / Keyword_static AssignmentExpr)
/// / TypeQual+ AssignmentExpr?
/// / AssignmentExpr
fn arrayDeclarator(parser: *Parser, lbracket: TokenIndex) !*Node.Array {
const arr = try parser.arena.create(Node.Array);
arr.* = .{
.lbracket = lbracket,
.inner = .Inferred,
.rbracket = undefined,
};
if (parser.eatToken(.Asterisk)) |tok| {
arr.inner = .{ .Unspecified = tok };
} else {
// TODO
}
arr.rbracket = try parser.expectToken(.RBracket);
return arr;
}
/// Params <- ParamDecl (COMMA ParamDecl)* (COMMA ELLIPSIS)?
/// ParamDecl <- DeclSpec (Declarator / AbstractDeclarator)
fn paramDecl(parser: *Parser, dr: *Node.Declarator) !void {
var old_style = false;
while (true) {
var ds = Node.DeclSpec{};
if (try parser.declSpec(&ds)) {
//TODO
// TODO try parser.declareSymbol(ds.type_spec, dr);
} else if (parser.eatToken(.Identifier)) |tok| {
old_style = true;
} else if (parser.eatToken(.Ellipsis)) |tok| {
// TODO
}
}
}
/// Expr <- AssignmentExpr (COMMA Expr)*
fn expr(parser: *Parser) Error!?*Expr {
@panic("TODO");
}
/// AssignmentExpr
/// <- ConditionalExpr // TODO recursive?
/// / UnaryExpr (EQUAL / ASTERISKEQUAL / SLASHEQUAL / PERCENTEQUAL / PLUSEQUAL / MINUSEQUA /
/// / ANGLEBRACKETANGLEBRACKETLEFTEQUAL / ANGLEBRACKETANGLEBRACKETRIGHTEQUAL /
/// / AMPERSANDEQUAL / CARETEQUAL / PIPEEQUAL) AssignmentExpr
fn assignmentExpr(parser: *Parser) !?*Expr {
@panic("TODO");
}
/// ConstExpr <- ConditionalExpr
fn constExpr(parser: *Parser) Error!?*Expr {
const start = parser.it.index;
const expression = try parser.conditionalExpr();
if (expression != null and expression.?.value == .None)
return parser.err(.{
.ConsExpr = start,
});
return expression;
}
/// ConditionalExpr <- LogicalOrExpr (QUESTIONMARK Expr COLON ConditionalExpr)?
fn conditionalExpr(parser: *Parser) Error!?*Expr {
@panic("TODO");
}
/// LogicalOrExpr <- LogicalAndExpr (PIPEPIPE LogicalOrExpr)*
fn logicalOrExpr(parser: *Parser) !*Node {
const lhs = (try parser.logicalAndExpr()) orelse return null;
}
/// LogicalAndExpr <- BinOrExpr (AMPERSANDAMPERSAND LogicalAndExpr)*
fn logicalAndExpr(parser: *Parser) !*Node {
@panic("TODO");
}
/// BinOrExpr <- BinXorExpr (PIPE BinOrExpr)*
fn binOrExpr(parser: *Parser) !*Node {
@panic("TODO");
}
/// BinXorExpr <- BinAndExpr (CARET BinXorExpr)*
fn binXorExpr(parser: *Parser) !*Node {
@panic("TODO");
}
/// BinAndExpr <- EqualityExpr (AMPERSAND BinAndExpr)*
fn binAndExpr(parser: *Parser) !*Node {
@panic("TODO");
}
/// EqualityExpr <- ComparisionExpr ((EQUALEQUAL / BANGEQUAL) EqualityExpr)*
fn equalityExpr(parser: *Parser) !*Node {
@panic("TODO");
}
/// ComparisionExpr <- ShiftExpr (ANGLEBRACKETLEFT / ANGLEBRACKETLEFTEQUAL /ANGLEBRACKETRIGHT / ANGLEBRACKETRIGHTEQUAL) ComparisionExpr)*
fn comparisionExpr(parser: *Parser) !*Node {
@panic("TODO");
}
/// ShiftExpr <- AdditiveExpr (ANGLEBRACKETANGLEBRACKETLEFT / ANGLEBRACKETANGLEBRACKETRIGHT) ShiftExpr)*
fn shiftExpr(parser: *Parser) !*Node {
@panic("TODO");
}
/// AdditiveExpr <- MultiplicativeExpr (PLUS / MINUS) AdditiveExpr)*
fn additiveExpr(parser: *Parser) !*Node {
@panic("TODO");
}
/// MultiplicativeExpr <- UnaryExpr (ASTERISK / SLASH / PERCENT) MultiplicativeExpr)*
fn multiplicativeExpr(parser: *Parser) !*Node {
@panic("TODO");
}
/// UnaryExpr
/// <- LPAREN TypeName RPAREN UnaryExpr
/// / Keyword_sizeof LAPERN TypeName RPAREN
/// / Keyword_sizeof UnaryExpr
/// / Keyword_alignof LAPERN TypeName RPAREN
/// / (AMPERSAND / ASTERISK / PLUS / PLUSPLUS / MINUS / MINUSMINUS / TILDE / BANG) UnaryExpr
/// / PrimaryExpr PostFixExpr*
fn unaryExpr(parser: *Parser) !*Node {
@panic("TODO");
}
/// PrimaryExpr
/// <- IDENTIFIER
/// / INTEGERLITERAL / FLOATLITERAL / STRINGLITERAL / CHARLITERAL
/// / LPAREN Expr RPAREN
/// / Keyword_generic LPAREN AssignmentExpr (COMMA Generic)+ RPAREN
fn primaryExpr(parser: *Parser) !*Node {
@panic("TODO");
}
/// Generic
/// <- TypeName COLON AssignmentExpr
/// / Keyword_default COLON AssignmentExpr
fn generic(parser: *Parser) !*Node {
@panic("TODO");
}
/// PostFixExpr
/// <- LPAREN TypeName RPAREN LBRACE Initializers RBRACE
/// / LBRACKET Expr RBRACKET
/// / LPAREN (AssignmentExpr (COMMA AssignmentExpr)*)? RPAREN
/// / (PERIOD / ARROW) IDENTIFIER
/// / (PLUSPLUS / MINUSMINUS)
fn postFixExpr(parser: *Parser) !*Node {
@panic("TODO");
}
/// Initializers <- ((Designator+ EQUAL)? Initializer COMMA)* (Designator+ EQUAL)? Initializer COMMA?
fn initializers(parser: *Parser) !*Node {
@panic("TODO");
}
/// Initializer
/// <- LBRACE Initializers RBRACE
/// / AssignmentExpr
fn initializer(parser: *Parser, dr: *Node.Declarator) Error!?*Node {
@panic("TODO");
}
/// Designator
/// <- LBRACKET ConstExpr RBRACKET
/// / PERIOD IDENTIFIER
fn designator(parser: *Parser) !*Node {
@panic("TODO");
}
/// CompoundStmt <- LBRACE (Declaration / Stmt)* RBRACE
fn compoundStmt(parser: *Parser) Error!?*Node {
const lbrace = parser.eatToken(.LBrace) orelse return null;
try parser.pushScope(.Block);
defer parser.popScope();
const body_node = try parser.arena.create(Node.CompoundStmt);
body_node.* = .{
.lbrace = lbrace,
.statements = Node.CompoundStmt.StmtList.init(parser.arena),
.rbrace = undefined,
};
while (true) {
if (parser.eatToken(.RBRACE)) |rbrace| {
body_node.rbrace = rbrace;
break;
}
try body_node.statements.push((try parser.declaration()) orelse (try parser.stmt()));
}
return &body_node.base;
}
/// Stmt
/// <- CompoundStmt
/// / Keyword_if LPAREN Expr RPAREN Stmt (Keyword_ELSE Stmt)?
/// / Keyword_switch LPAREN Expr RPAREN Stmt
/// / Keyword_while LPAREN Expr RPAREN Stmt
/// / Keyword_do statement Keyword_while LPAREN Expr RPAREN SEMICOLON
/// / Keyword_for LPAREN (Declaration / ExprStmt) ExprStmt Expr? RPAREN Stmt
/// / Keyword_default COLON Stmt
/// / Keyword_case ConstExpr COLON Stmt
/// / Keyword_goto IDENTIFIER SEMICOLON
/// / Keyword_continue SEMICOLON
/// / Keyword_break SEMICOLON
/// / Keyword_return Expr? SEMICOLON
/// / IDENTIFIER COLON Stmt
/// / ExprStmt
fn stmt(parser: *Parser) Error!*Node {
if (try parser.compoundStmt()) |node| return node;
if (parser.eatToken(.Keyword_if)) |tok| {
const node = try parser.arena.create(Node.IfStmt);
_ = try parser.expectToken(.LParen);
node.* = .{
.@"if" = tok,
.cond = (try parser.expr()) orelse return parser.err(.{
.ExpectedExpr = .{ .token = parser.it.index },
}),
.body = undefined,
.@"else" = null,
};
_ = try parser.expectToken(.RParen);
node.body = try parser.stmt();
if (parser.eatToken(.Keyword_else)) |else_tok| {
node.@"else" = .{
.tok = else_tok,
.body = try parser.stmt(),
};
}
return &node.base;
}
if (parser.eatToken(.Keyword_while)) |tok| {
try parser.pushScope(.Loop);
defer parser.popScope();
_ = try parser.expectToken(.LParen);
const cond = (try parser.expr()) orelse return parser.err(.{
.ExpectedExpr = .{ .token = parser.it.index },
});
const rparen = try parser.expectToken(.RParen);
const node = try parser.arena.create(Node.WhileStmt);
node.* = .{
.@"while" = tok,
.cond = cond,
.rparen = rparen,
.body = try parser.stmt(),
.semicolon = try parser.expectToken(.Semicolon),
};
return &node.base;
}
if (parser.eatToken(.Keyword_do)) |tok| {
try parser.pushScope(.Loop);
defer parser.popScope();
const body = try parser.stmt();
_ = try parser.expectToken(.LParen);
const cond = (try parser.expr()) orelse return parser.err(.{
.ExpectedExpr = .{ .token = parser.it.index },
});
_ = try parser.expectToken(.RParen);
const node = try parser.arena.create(Node.DoStmt);
node.* = .{
.do = tok,
.body = body,
.cond = cond,
.@"while" = @"while",
.semicolon = try parser.expectToken(.Semicolon),
};
return &node.base;
}
if (parser.eatToken(.Keyword_for)) |tok| {
try parser.pushScope(.Loop);
defer parser.popScope();
_ = try parser.expectToken(.LParen);
const init = if (try parser.declaration()) |decl| blk: {
// TODO disallow storage class other than auto and register
break :blk decl;
} else try parser.exprStmt();
const cond = try parser.expr();
const semicolon = try parser.expectToken(.Semicolon);
const incr = try parser.expr();
const rparen = try parser.expectToken(.RParen);
const node = try parser.arena.create(Node.ForStmt);
node.* = .{
.@"for" = tok,
.init = init,
.cond = cond,
.semicolon = semicolon,
.incr = incr,
.rparen = rparen,
.body = try parser.stmt(),
};
return &node.base;
}
if (parser.eatToken(.Keyword_switch)) |tok| {
try parser.pushScope(.Switch);
defer parser.popScope();
_ = try parser.expectToken(.LParen);
const switch_expr = try parser.exprStmt();
const rparen = try parser.expectToken(.RParen);
const node = try parser.arena.create(Node.SwitchStmt);
node.* = .{
.@"switch" = tok,
.expr = switch_expr,
.rparen = rparen,
.body = try parser.stmt(),
};
return &node.base;
}
if (parser.eatToken(.Keyword_default)) |tok| {
_ = try parser.expectToken(.Colon);
const node = try parser.arena.create(Node.LabeledStmt);
node.* = .{
.kind = .{ .Default = tok },
.stmt = try parser.stmt(),
};
return &node.base;
}
if (parser.eatToken(.Keyword_case)) |tok| {
_ = try parser.expectToken(.Colon);
const node = try parser.arena.create(Node.LabeledStmt);
node.* = .{
.kind = .{ .Case = tok },
.stmt = try parser.stmt(),
};
return &node.base;
}
if (parser.eatToken(.Keyword_goto)) |tok| {
const node = try parser.arena.create(Node.JumpStmt);
node.* = .{
.ltoken = tok,
.kind = .{ .Goto = tok },
.semicolon = try parser.expectToken(.Semicolon),
};
return &node.base;
}
if (parser.eatToken(.Keyword_continue)) |tok| {
const node = try parser.arena.create(Node.JumpStmt);
node.* = .{
.ltoken = tok,
.kind = .Continue,
.semicolon = try parser.expectToken(.Semicolon),
};
return &node.base;
}
if (parser.eatToken(.Keyword_break)) |tok| {
const node = try parser.arena.create(Node.JumpStmt);
node.* = .{
.ltoken = tok,
.kind = .Break,
.semicolon = try parser.expectToken(.Semicolon),
};
return &node.base;
}
if (parser.eatToken(.Keyword_return)) |tok| {
const node = try parser.arena.create(Node.JumpStmt);
node.* = .{
.ltoken = tok,
.kind = .{ .Return = try parser.expr() },
.semicolon = try parser.expectToken(.Semicolon),
};
return &node.base;
}
if (parser.eatToken(.Identifier)) |tok| {
if (parser.eatToken(.Colon)) |_| {
const node = try parser.arena.create(Node.LabeledStmt);
node.* = .{
.kind = .{ .Label = tok },
.stmt = try parser.stmt(),
};
return &node.base;
}
parser.putBackToken(tok);
}
return parser.exprStmt();
}
/// ExprStmt <- Expr? SEMICOLON
fn exprStmt(parser: *Parser) !*Node {
const node = try parser.arena.create(Node.ExprStmt);
node.* = .{
.expr = try parser.expr(),
.semicolon = try parser.expectToken(.Semicolon),
};
return &node.base;
}
fn eatToken(parser: *Parser, id: @TagType(Token.Id)) ?TokenIndex {
while (true) {
switch ((parser.it.next() orelse return null).id) {
.LineComment, .MultiLineComment, .Nl => continue,
else => |next_id| if (next_id == id) {
return parser.it.index;
} else {
_ = parser.it.prev();
return null;
},
}
}
}
fn expectToken(parser: *Parser, id: @TagType(Token.Id)) Error!TokenIndex {
while (true) {
switch ((parser.it.next() orelse return error.ParseError).id) {
.LineComment, .MultiLineComment, .Nl => continue,
else => |next_id| if (next_id != id) {
return parser.err(.{
.ExpectedToken = .{ .token = parser.it.index, .expected_id = id },
});
} else {
return parser.it.index;
},
}
}
}
fn putBackToken(parser: *Parser, putting_back: TokenIndex) void {
while (true) {
const prev_tok = parser.it.next() orelse return;
switch (prev_tok.id) {
.LineComment, .MultiLineComment, .Nl => continue,
else => {
assert(parser.it.list.at(putting_back) == prev_tok);
return;
},
}
}
}
fn err(parser: *Parser, msg: ast.Error) Error {
try parser.tree.msgs.push(.{
.kind = .Error,
.inner = msg,
});
return error.ParseError;
}
fn warn(parser: *Parser, msg: ast.Error) Error!void {
const is_warning = switch (parser.options.warn_as_err) {
.None => true,
.Some => |list| for (list) |item| (if (item == msg) break false) else true,
.All => false,
};
try parser.tree.msgs.push(.{
.kind = if (is_warning) .Warning else .Error,
.inner = msg,
});
if (!is_warning) return error.ParseError;
}
fn note(parser: *Parser, msg: ast.Error) Error!void {
try parser.tree.msgs.push(.{
.kind = .Note,
.inner = msg,
});
}
};