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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-28 13:14:23 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-28 13:14:23 +0000 |
commit | 73df946d56c74384511a194dd01dbe099584fd1a (patch) | |
tree | fd0bcea490dd81327ddfbb31e215439672c9a068 /src/runtime/error.go | |
parent | Initial commit. (diff) | |
download | golang-1.16-73df946d56c74384511a194dd01dbe099584fd1a.tar.xz golang-1.16-73df946d56c74384511a194dd01dbe099584fd1a.zip |
Adding upstream version 1.16.10.upstream/1.16.10upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'src/runtime/error.go')
-rw-r--r-- | src/runtime/error.go | 327 |
1 files changed, 327 insertions, 0 deletions
diff --git a/src/runtime/error.go b/src/runtime/error.go new file mode 100644 index 0000000..9e6cdf3 --- /dev/null +++ b/src/runtime/error.go @@ -0,0 +1,327 @@ +// Copyright 2010 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package runtime + +import "internal/bytealg" + +// The Error interface identifies a run time error. +type Error interface { + error + + // RuntimeError is a no-op function but + // serves to distinguish types that are run time + // errors from ordinary errors: a type is a + // run time error if it has a RuntimeError method. + RuntimeError() +} + +// A TypeAssertionError explains a failed type assertion. +type TypeAssertionError struct { + _interface *_type + concrete *_type + asserted *_type + missingMethod string // one method needed by Interface, missing from Concrete +} + +func (*TypeAssertionError) RuntimeError() {} + +func (e *TypeAssertionError) Error() string { + inter := "interface" + if e._interface != nil { + inter = e._interface.string() + } + as := e.asserted.string() + if e.concrete == nil { + return "interface conversion: " + inter + " is nil, not " + as + } + cs := e.concrete.string() + if e.missingMethod == "" { + msg := "interface conversion: " + inter + " is " + cs + ", not " + as + if cs == as { + // provide slightly clearer error message + if e.concrete.pkgpath() != e.asserted.pkgpath() { + msg += " (types from different packages)" + } else { + msg += " (types from different scopes)" + } + } + return msg + } + return "interface conversion: " + cs + " is not " + as + + ": missing method " + e.missingMethod +} + +//go:nosplit +// itoa converts val to a decimal representation. The result is +// written somewhere within buf and the location of the result is returned. +// buf must be at least 20 bytes. +func itoa(buf []byte, val uint64) []byte { + i := len(buf) - 1 + for val >= 10 { + buf[i] = byte(val%10 + '0') + i-- + val /= 10 + } + buf[i] = byte(val + '0') + return buf[i:] +} + +// An errorString represents a runtime error described by a single string. +type errorString string + +func (e errorString) RuntimeError() {} + +func (e errorString) Error() string { + return "runtime error: " + string(e) +} + +type errorAddressString struct { + msg string // error message + addr uintptr // memory address where the error occurred +} + +func (e errorAddressString) RuntimeError() {} + +func (e errorAddressString) Error() string { + return "runtime error: " + e.msg +} + +// Addr returns the memory address where a fault occurred. +// The address provided is best-effort. +// The veracity of the result may depend on the platform. +// Errors providing this method will only be returned as +// a result of using runtime/debug.SetPanicOnFault. +func (e errorAddressString) Addr() uintptr { + return e.addr +} + +// plainError represents a runtime error described a string without +// the prefix "runtime error: " after invoking errorString.Error(). +// See Issue #14965. +type plainError string + +func (e plainError) RuntimeError() {} + +func (e plainError) Error() string { + return string(e) +} + +// A boundsError represents an indexing or slicing operation gone wrong. +type boundsError struct { + x int64 + y int + // Values in an index or slice expression can be signed or unsigned. + // That means we'd need 65 bits to encode all possible indexes, from -2^63 to 2^64-1. + // Instead, we keep track of whether x should be interpreted as signed or unsigned. + // y is known to be nonnegative and to fit in an int. + signed bool + code boundsErrorCode +} + +type boundsErrorCode uint8 + +const ( + boundsIndex boundsErrorCode = iota // s[x], 0 <= x < len(s) failed + + boundsSliceAlen // s[?:x], 0 <= x <= len(s) failed + boundsSliceAcap // s[?:x], 0 <= x <= cap(s) failed + boundsSliceB // s[x:y], 0 <= x <= y failed (but boundsSliceA didn't happen) + + boundsSlice3Alen // s[?:?:x], 0 <= x <= len(s) failed + boundsSlice3Acap // s[?:?:x], 0 <= x <= cap(s) failed + boundsSlice3B // s[?:x:y], 0 <= x <= y failed (but boundsSlice3A didn't happen) + boundsSlice3C // s[x:y:?], 0 <= x <= y failed (but boundsSlice3A/B didn't happen) + + // Note: in the above, len(s) and cap(s) are stored in y +) + +// boundsErrorFmts provide error text for various out-of-bounds panics. +// Note: if you change these strings, you should adjust the size of the buffer +// in boundsError.Error below as well. +var boundsErrorFmts = [...]string{ + boundsIndex: "index out of range [%x] with length %y", + boundsSliceAlen: "slice bounds out of range [:%x] with length %y", + boundsSliceAcap: "slice bounds out of range [:%x] with capacity %y", + boundsSliceB: "slice bounds out of range [%x:%y]", + boundsSlice3Alen: "slice bounds out of range [::%x] with length %y", + boundsSlice3Acap: "slice bounds out of range [::%x] with capacity %y", + boundsSlice3B: "slice bounds out of range [:%x:%y]", + boundsSlice3C: "slice bounds out of range [%x:%y:]", +} + +// boundsNegErrorFmts are overriding formats if x is negative. In this case there's no need to report y. +var boundsNegErrorFmts = [...]string{ + boundsIndex: "index out of range [%x]", + boundsSliceAlen: "slice bounds out of range [:%x]", + boundsSliceAcap: "slice bounds out of range [:%x]", + boundsSliceB: "slice bounds out of range [%x:]", + boundsSlice3Alen: "slice bounds out of range [::%x]", + boundsSlice3Acap: "slice bounds out of range [::%x]", + boundsSlice3B: "slice bounds out of range [:%x:]", + boundsSlice3C: "slice bounds out of range [%x::]", +} + +func (e boundsError) RuntimeError() {} + +func appendIntStr(b []byte, v int64, signed bool) []byte { + if signed && v < 0 { + b = append(b, '-') + v = -v + } + var buf [20]byte + b = append(b, itoa(buf[:], uint64(v))...) + return b +} + +func (e boundsError) Error() string { + fmt := boundsErrorFmts[e.code] + if e.signed && e.x < 0 { + fmt = boundsNegErrorFmts[e.code] + } + // max message length is 99: "runtime error: slice bounds out of range [::%x] with capacity %y" + // x can be at most 20 characters. y can be at most 19. + b := make([]byte, 0, 100) + b = append(b, "runtime error: "...) + for i := 0; i < len(fmt); i++ { + c := fmt[i] + if c != '%' { + b = append(b, c) + continue + } + i++ + switch fmt[i] { + case 'x': + b = appendIntStr(b, e.x, e.signed) + case 'y': + b = appendIntStr(b, int64(e.y), true) + } + } + return string(b) +} + +type stringer interface { + String() string +} + +// printany prints an argument passed to panic. +// If panic is called with a value that has a String or Error method, +// it has already been converted into a string by preprintpanics. +func printany(i interface{}) { + switch v := i.(type) { + case nil: + print("nil") + case bool: + print(v) + case int: + print(v) + case int8: + print(v) + case int16: + print(v) + case int32: + print(v) + case int64: + print(v) + case uint: + print(v) + case uint8: + print(v) + case uint16: + print(v) + case uint32: + print(v) + case uint64: + print(v) + case uintptr: + print(v) + case float32: + print(v) + case float64: + print(v) + case complex64: + print(v) + case complex128: + print(v) + case string: + print(v) + default: + printanycustomtype(i) + } +} + +func printanycustomtype(i interface{}) { + eface := efaceOf(&i) + typestring := eface._type.string() + + switch eface._type.kind { + case kindString: + print(typestring, `("`, *(*string)(eface.data), `")`) + case kindBool: + print(typestring, "(", *(*bool)(eface.data), ")") + case kindInt: + print(typestring, "(", *(*int)(eface.data), ")") + case kindInt8: + print(typestring, "(", *(*int8)(eface.data), ")") + case kindInt16: + print(typestring, "(", *(*int16)(eface.data), ")") + case kindInt32: + print(typestring, "(", *(*int32)(eface.data), ")") + case kindInt64: + print(typestring, "(", *(*int64)(eface.data), ")") + case kindUint: + print(typestring, "(", *(*uint)(eface.data), ")") + case kindUint8: + print(typestring, "(", *(*uint8)(eface.data), ")") + case kindUint16: + print(typestring, "(", *(*uint16)(eface.data), ")") + case kindUint32: + print(typestring, "(", *(*uint32)(eface.data), ")") + case kindUint64: + print(typestring, "(", *(*uint64)(eface.data), ")") + case kindUintptr: + print(typestring, "(", *(*uintptr)(eface.data), ")") + case kindFloat32: + print(typestring, "(", *(*float32)(eface.data), ")") + case kindFloat64: + print(typestring, "(", *(*float64)(eface.data), ")") + case kindComplex64: + print(typestring, *(*complex64)(eface.data)) + case kindComplex128: + print(typestring, *(*complex128)(eface.data)) + default: + print("(", typestring, ") ", eface.data) + } +} + +// panicwrap generates a panic for a call to a wrapped value method +// with a nil pointer receiver. +// +// It is called from the generated wrapper code. +func panicwrap() { + pc := getcallerpc() + name := funcname(findfunc(pc)) + // name is something like "main.(*T).F". + // We want to extract pkg ("main"), typ ("T"), and meth ("F"). + // Do it by finding the parens. + i := bytealg.IndexByteString(name, '(') + if i < 0 { + throw("panicwrap: no ( in " + name) + } + pkg := name[:i-1] + if i+2 >= len(name) || name[i-1:i+2] != ".(*" { + throw("panicwrap: unexpected string after package name: " + name) + } + name = name[i+2:] + i = bytealg.IndexByteString(name, ')') + if i < 0 { + throw("panicwrap: no ) in " + name) + } + if i+2 >= len(name) || name[i:i+2] != ")." { + throw("panicwrap: unexpected string after type name: " + name) + } + typ := name[:i] + meth := name[i+2:] + panic(plainError("value method " + pkg + "." + typ + "." + meth + " called using nil *" + typ + " pointer")) +} |