Merge pull request #759 from zig-lang/error-sets

Error Sets

2 files changed, 54 insertions, 54 deletions

diff --git a/std/debug/failing_allocator.zig b/std/debug/failing_allocator.zig
index cc5a8bc045..f876b7902d 100644
--- a/std/debug/failing_allocator.zig
+++ b/std/debug/failing_allocator.zig
@@ -28,7 +28,7 @@ pub const FailingAllocator = struct {
         };
     }
 
-    fn alloc(allocator: &mem.Allocator, n: usize, alignment: u29) %[]u8 {
+    fn alloc(allocator: &mem.Allocator, n: usize, alignment: u29) ![]u8 {
         const self = @fieldParentPtr(FailingAllocator, "allocator", allocator);
         if (self.index == self.fail_index) {
             return error.OutOfMemory;
@@ -39,7 +39,7 @@ pub const FailingAllocator = struct {
         return result;
     }
 
-    fn realloc(allocator: &mem.Allocator, old_mem: []u8, new_size: usize, alignment: u29) %[]u8 {
+    fn realloc(allocator: &mem.Allocator, old_mem: []u8, new_size: usize, alignment: u29) ![]u8 {
         const self = @fieldParentPtr(FailingAllocator, "allocator", allocator);
         if (new_size <= old_mem.len) {
             self.freed_bytes += old_mem.len - new_size;
diff --git a/std/debug/index.zig b/std/debug/index.zig
index ccf5f6d413..2bb03a6706 100644
--- a/std/debug/index.zig
+++ b/std/debug/index.zig
@@ -10,26 +10,17 @@ const builtin = @import("builtin");
 
 pub const FailingAllocator = @import("failing_allocator.zig").FailingAllocator;
 
-error MissingDebugInfo;
-error InvalidDebugInfo;
-error UnsupportedDebugInfo;
-error UnknownObjectFormat;
-error TodoSupportCoffDebugInfo;
-error TodoSupportMachoDebugInfo;
-error TodoSupportCOFFDebugInfo;
-
-
 /// Tries to write to stderr, unbuffered, and ignores any error returned.
 /// Does not append a newline.
 /// TODO atomic/multithread support
 var stderr_file: io.File = undefined;
 var stderr_file_out_stream: io.FileOutStream = undefined;
-var stderr_stream: ?&io.OutStream = null;
+var stderr_stream: ?&io.OutStream(io.FileOutStream.Error) = null;
 pub fn warn(comptime fmt: []const u8, args: ...) void {
     const stderr = getStderrStream() catch return;
     stderr.print(fmt, args) catch return;
 }
-fn getStderrStream() %&io.OutStream {
+fn getStderrStream() !&io.OutStream(io.FileOutStream.Error) {
     if (stderr_stream) |st| {
         return st;
     } else {
@@ -42,7 +33,7 @@ fn getStderrStream() %&io.OutStream {
 }
 
 var self_debug_info: ?&ElfStackTrace = null;
-pub fn getSelfDebugInfo() %&ElfStackTrace {
+pub fn getSelfDebugInfo() !&ElfStackTrace {
     if (self_debug_info) |info| {
         return info;
     } else {
@@ -149,11 +140,8 @@ const WHITE = "\x1b[37;1m";
 const DIM = "\x1b[2m";
 const RESET = "\x1b[0m";
 
-error PathNotFound;
-error InvalidDebugInfo;
-
-pub fn writeStackTrace(stack_trace: &const builtin.StackTrace, out_stream: &io.OutStream, allocator: &mem.Allocator,
-    debug_info: &ElfStackTrace, tty_color: bool) %void
+pub fn writeStackTrace(stack_trace: &const builtin.StackTrace, out_stream: var, allocator: &mem.Allocator,
+    debug_info: &ElfStackTrace, tty_color: bool) !void
 {
     var frame_index: usize = undefined;
     var frames_left: usize = undefined;
@@ -174,8 +162,8 @@ pub fn writeStackTrace(stack_trace: &const builtin.StackTrace, out_stream: &io.O
     }
 }
 
-pub fn writeCurrentStackTrace(out_stream: &io.OutStream, allocator: &mem.Allocator,
-    debug_info: &ElfStackTrace, tty_color: bool, ignore_frame_count: usize) %void
+pub fn writeCurrentStackTrace(out_stream: var, allocator: &mem.Allocator,
+    debug_info: &ElfStackTrace, tty_color: bool, ignore_frame_count: usize) !void
 {
     var ignored_count: usize = 0;
 
@@ -191,7 +179,7 @@ pub fn writeCurrentStackTrace(out_stream: &io.OutStream, allocator: &mem.Allocat
     }
 }
 
-fn printSourceAtAddress(debug_info: &ElfStackTrace, out_stream: &io.OutStream, address: usize) %void {
+fn printSourceAtAddress(debug_info: &ElfStackTrace, out_stream: var, address: usize) !void {
     if (builtin.os == builtin.Os.windows) {
         return error.UnsupportedDebugInfo;
     }
@@ -221,7 +209,7 @@ fn printSourceAtAddress(debug_info: &ElfStackTrace, out_stream: &io.OutStream, a
                 try out_stream.write(GREEN ++ "^" ++ RESET ++ "\n");
             }
         } else |err| switch (err) {
-            error.EndOfFile, error.PathNotFound => {},
+            error.EndOfFile => {},
             else => return err,
         }
     } else |err| switch (err) {
@@ -232,7 +220,7 @@ fn printSourceAtAddress(debug_info: &ElfStackTrace, out_stream: &io.OutStream, a
     }
 }
 
-pub fn openSelfDebugInfo(allocator: &mem.Allocator) %&ElfStackTrace {
+pub fn openSelfDebugInfo(allocator: &mem.Allocator) !&ElfStackTrace {
     switch (builtin.object_format) {
         builtin.ObjectFormat.elf => {
             const st = try allocator.create(ElfStackTrace);
@@ -276,7 +264,7 @@ pub fn openSelfDebugInfo(allocator: &mem.Allocator) %&ElfStackTrace {
     }
 }
 
-fn printLineFromFile(allocator: &mem.Allocator, out_stream: &io.OutStream, line_info: &const LineInfo) %void {
+fn printLineFromFile(allocator: &mem.Allocator, out_stream: var, line_info: &const LineInfo) !void {
     var f = try io.File.openRead(line_info.file_name, allocator);
     defer f.close();
     // TODO fstat and make sure that the file has the correct size
@@ -324,7 +312,7 @@ pub const ElfStackTrace = struct {
         return self.abbrev_table_list.allocator;
     }
 
-    pub fn readString(self: &ElfStackTrace) %[]u8 {
+    pub fn readString(self: &ElfStackTrace) ![]u8 {
         var in_file_stream = io.FileInStream.init(&self.self_exe_file);
         const in_stream = &in_file_stream.stream;
         return readStringRaw(self.allocator(), in_stream);
@@ -387,7 +375,7 @@ const Constant = struct {
     payload: []u8,
     signed: bool,
 
-    fn asUnsignedLe(self: &const Constant) %u64 {
+    fn asUnsignedLe(self: &const Constant) !u64 {
         if (self.payload.len > @sizeOf(u64))
             return error.InvalidDebugInfo;
         if (self.signed)
@@ -414,7 +402,7 @@ const Die = struct {
         return null;
     }
 
-    fn getAttrAddr(self: &const Die, id: u64) %u64 {
+    fn getAttrAddr(self: &const Die, id: u64) !u64 {
         const form_value = self.getAttr(id) ?? return error.MissingDebugInfo;
         return switch (*form_value) {
             FormValue.Address => |value| value,
@@ -422,7 +410,7 @@ const Die = struct {
         };
     }
 
-    fn getAttrSecOffset(self: &const Die, id: u64) %u64 {
+    fn getAttrSecOffset(self: &const Die, id: u64) !u64 {
         const form_value = self.getAttr(id) ?? return error.MissingDebugInfo;
         return switch (*form_value) {
             FormValue.Const => |value| value.asUnsignedLe(),
@@ -431,7 +419,7 @@ const Die = struct {
         };
     }
 
-    fn getAttrUnsignedLe(self: &const Die, id: u64) %u64 {
+    fn getAttrUnsignedLe(self: &const Die, id: u64) !u64 {
         const form_value = self.getAttr(id) ?? return error.MissingDebugInfo;
         return switch (*form_value) {
             FormValue.Const => |value| value.asUnsignedLe(),
@@ -439,7 +427,7 @@ const Die = struct {
         };
     }
 
-    fn getAttrString(self: &const Die, st: &ElfStackTrace, id: u64) %[]u8 {
+    fn getAttrString(self: &const Die, st: &ElfStackTrace, id: u64) ![]u8 {
         const form_value = self.getAttr(id) ?? return error.MissingDebugInfo;
         return switch (*form_value) {
             FormValue.String => |value| value,
@@ -512,7 +500,7 @@ const LineNumberProgram = struct {
         };
     }
 
-    pub fn checkLineMatch(self: &LineNumberProgram) %?LineInfo {
+    pub fn checkLineMatch(self: &LineNumberProgram) !?LineInfo {
         if (self.target_address >= self.prev_address and self.target_address < self.address) {
             const file_entry = if (self.prev_file == 0) {
                 return error.MissingDebugInfo;
@@ -544,7 +532,7 @@ const LineNumberProgram = struct {
     }
 };
 
-fn readStringRaw(allocator: &mem.Allocator, in_stream: &io.InStream) %[]u8 {
+fn readStringRaw(allocator: &mem.Allocator, in_stream: var) ![]u8 {
     var buf = ArrayList(u8).init(allocator);
     while (true) {
         const byte = try in_stream.readByte();
@@ -555,58 +543,70 @@ fn readStringRaw(allocator: &mem.Allocator, in_stream: &io.InStream) %[]u8 {
     return buf.toSlice();
 }
 
-fn getString(st: &ElfStackTrace, offset: u64) %[]u8 {
+fn getString(st: &ElfStackTrace, offset: u64) ![]u8 {
     const pos = st.debug_str.offset + offset;
     try st.self_exe_file.seekTo(pos);
     return st.readString();
 }
 
-fn readAllocBytes(allocator: &mem.Allocator, in_stream: &io.InStream, size: usize) %[]u8 {
+fn readAllocBytes(allocator: &mem.Allocator, in_stream: var, size: usize) ![]u8 {
     const buf = try global_allocator.alloc(u8, size);
     errdefer global_allocator.free(buf);
     if ((try in_stream.read(buf)) < size) return error.EndOfFile;
     return buf;
 }
 
-fn parseFormValueBlockLen(allocator: &mem.Allocator, in_stream: &io.InStream, size: usize) %FormValue {
+fn parseFormValueBlockLen(allocator: &mem.Allocator, in_stream: var, size: usize) !FormValue {
     const buf = try readAllocBytes(allocator, in_stream, size);
     return FormValue { .Block = buf };
 }
 
-fn parseFormValueBlock(allocator: &mem.Allocator, in_stream: &io.InStream, size: usize) %FormValue {
+fn parseFormValueBlock(allocator: &mem.Allocator, in_stream: var, size: usize) !FormValue {
     const block_len = try in_stream.readVarInt(builtin.Endian.Little, usize, size);
     return parseFormValueBlockLen(allocator, in_stream, block_len);
 }
 
-fn parseFormValueConstant(allocator: &mem.Allocator, in_stream: &io.InStream, signed: bool, size: usize) %FormValue {
+fn parseFormValueConstant(allocator: &mem.Allocator, in_stream: var, signed: bool, size: usize) !FormValue {
     return FormValue { .Const = Constant {
         .signed = signed,
         .payload = try readAllocBytes(allocator, in_stream, size),
     }};
 }
 
-fn parseFormValueDwarfOffsetSize(in_stream: &io.InStream, is_64: bool) %u64 {
+fn parseFormValueDwarfOffsetSize(in_stream: var, is_64: bool) !u64 {
     return if (is_64) try in_stream.readIntLe(u64)
     else u64(try in_stream.readIntLe(u32)) ;
 }
 
-fn parseFormValueTargetAddrSize(in_stream: &io.InStream) %u64 {
+fn parseFormValueTargetAddrSize(in_stream: var) !u64 {
     return if (@sizeOf(usize) == 4) u64(try in_stream.readIntLe(u32))
     else if (@sizeOf(usize) == 8) try in_stream.readIntLe(u64)
     else unreachable;
 }
 
-fn parseFormValueRefLen(allocator: &mem.Allocator, in_stream: &io.InStream, size: usize) %FormValue {
+fn parseFormValueRefLen(allocator: &mem.Allocator, in_stream: var, size: usize) !FormValue {
     const buf = try readAllocBytes(allocator, in_stream, size);
     return FormValue { .Ref = buf };
 }
 
-fn parseFormValueRef(allocator: &mem.Allocator, in_stream: &io.InStream, comptime T: type) %FormValue {
+fn parseFormValueRef(allocator: &mem.Allocator, in_stream: var, comptime T: type) !FormValue {
     const block_len = try in_stream.readIntLe(T);
     return parseFormValueRefLen(allocator, in_stream, block_len);
 }
 
-fn parseFormValue(allocator: &mem.Allocator, in_stream: &io.InStream, form_id: u64, is_64: bool) %FormValue {
+const ParseFormValueError = error {
+    EndOfStream,
+    Io,
+    BadFd,
+    Unexpected,
+    InvalidDebugInfo,
+    EndOfFile,
+    OutOfMemory,
+};
+
+fn parseFormValue(allocator: &mem.Allocator, in_stream: var, form_id: u64, is_64: bool)
+    ParseFormValueError!FormValue
+{
     return switch (form_id) {
         DW.FORM_addr => FormValue { .Address = try parseFormValueTargetAddrSize(in_stream) },
         DW.FORM_block1 => parseFormValueBlock(allocator, in_stream, 1),
@@ -656,7 +656,7 @@ fn parseFormValue(allocator: &mem.Allocator, in_stream: &io.InStream, form_id: u
     };
 }
 
-fn parseAbbrevTable(st: &ElfStackTrace) %AbbrevTable {
+fn parseAbbrevTable(st: &ElfStackTrace) !AbbrevTable {
     const in_file = &st.self_exe_file;
     var in_file_stream = io.FileInStream.init(in_file);
     const in_stream = &in_file_stream.stream;
@@ -688,7 +688,7 @@ fn parseAbbrevTable(st: &ElfStackTrace) %AbbrevTable {
 
 /// Gets an already existing AbbrevTable given the abbrev_offset, or if not found,
 /// seeks in the stream and parses it.
-fn getAbbrevTable(st: &ElfStackTrace, abbrev_offset: u64) %&const AbbrevTable {
+fn getAbbrevTable(st: &ElfStackTrace, abbrev_offset: u64) !&const AbbrevTable {
     for (st.abbrev_table_list.toSlice()) |*header| {
         if (header.offset == abbrev_offset) {
             return &header.table;
@@ -710,7 +710,7 @@ fn getAbbrevTableEntry(abbrev_table: &const AbbrevTable, abbrev_code: u64) ?&con
     return null;
 }
 
-fn parseDie(st: &ElfStackTrace, abbrev_table: &const AbbrevTable, is_64: bool) %Die {
+fn parseDie(st: &ElfStackTrace, abbrev_table: &const AbbrevTable, is_64: bool) !Die {
     const in_file = &st.self_exe_file;
     var in_file_stream = io.FileInStream.init(in_file);
     const in_stream = &in_file_stream.stream;
@@ -732,7 +732,7 @@ fn parseDie(st: &ElfStackTrace, abbrev_table: &const AbbrevTable, is_64: bool) %
     return result;
 }
 
-fn getLineNumberInfo(st: &ElfStackTrace, compile_unit: &const CompileUnit, target_address: usize) %LineInfo {
+fn getLineNumberInfo(st: &ElfStackTrace, compile_unit: &const CompileUnit, target_address: usize) !LineInfo {
     const compile_unit_cwd = try compile_unit.die.getAttrString(st, DW.AT_comp_dir);
 
     const in_file = &st.self_exe_file;
@@ -747,7 +747,7 @@ fn getLineNumberInfo(st: &ElfStackTrace, compile_unit: &const CompileUnit, targe
         try in_file.seekTo(this_offset);
 
         var is_64: bool = undefined;
-        const unit_length = try readInitialLength(in_stream, &is_64);
+        const unit_length = try readInitialLength(@typeOf(in_stream.readFn).ReturnType.ErrorSet, in_stream, &is_64);
         if (unit_length == 0)
             return error.MissingDebugInfo;
         const next_offset = unit_length + (if (is_64) usize(12) else usize(4));
@@ -910,7 +910,7 @@ fn getLineNumberInfo(st: &ElfStackTrace, compile_unit: &const CompileUnit, targe
     return error.MissingDebugInfo;
 }
 
-fn scanAllCompileUnits(st: &ElfStackTrace) %void {
+fn scanAllCompileUnits(st: &ElfStackTrace) !void {
     const debug_info_end = st.debug_info.offset + st.debug_info.size;
     var this_unit_offset = st.debug_info.offset;
     var cu_index: usize = 0;
@@ -922,7 +922,7 @@ fn scanAllCompileUnits(st: &ElfStackTrace) %void {
         try st.self_exe_file.seekTo(this_unit_offset);
 
         var is_64: bool = undefined;
-        const unit_length = try readInitialLength(in_stream, &is_64);
+        const unit_length = try readInitialLength(@typeOf(in_stream.readFn).ReturnType.ErrorSet, in_stream, &is_64);
         if (unit_length == 0)
             return;
         const next_offset = unit_length + (if (is_64) usize(12) else usize(4));
@@ -986,7 +986,7 @@ fn scanAllCompileUnits(st: &ElfStackTrace) %void {
     }
 }
 
-fn findCompileUnit(st: &ElfStackTrace, target_address: u64) %&const CompileUnit {
+fn findCompileUnit(st: &ElfStackTrace, target_address: u64) !&const CompileUnit {
     var in_file_stream = io.FileInStream.init(&st.self_exe_file);
     const in_stream = &in_file_stream.stream;
     for (st.compile_unit_list.toSlice()) |*compile_unit| {
@@ -1022,7 +1022,7 @@ fn findCompileUnit(st: &ElfStackTrace, target_address: u64) %&const CompileUnit
     return error.MissingDebugInfo;
 }
 
-fn readInitialLength(in_stream: &io.InStream, is_64: &bool) %u64 {
+fn readInitialLength(comptime E: type, in_stream: &io.InStream(E), is_64: &bool) !u64 {
     const first_32_bits = try in_stream.readIntLe(u32);
     *is_64 = (first_32_bits == 0xffffffff);
     if (*is_64) {
@@ -1033,7 +1033,7 @@ fn readInitialLength(in_stream: &io.InStream, is_64: &bool) %u64 {
     }
 }
 
-fn readULeb128(in_stream: &io.InStream) %u64 {
+fn readULeb128(in_stream: var) !u64 {
     var result: u64 = 0;
     var shift: usize = 0;
 
@@ -1054,7 +1054,7 @@ fn readULeb128(in_stream: &io.InStream) %u64 {
     }
 }
 
-fn readILeb128(in_stream: &io.InStream) %i64 {
+fn readILeb128(in_stream: var) !i64 {
     var result: i64 = 0;
     var shift: usize = 0;