throw away os._Error.

make some error types in a few packages

R=r
DELTA=110  (25 added, 46 deleted, 39 changed)
OCL=28382
CL=28561

11 files changed, 64 insertions, 85 deletions

diff --git a/src/lib/bufio/bufio.go b/src/lib/bufio/bufio.go
index 4c700eef4..f0e12931d 100644
--- a/src/lib/bufio/bufio.go
+++ b/src/lib/bufio/bufio.go
@@ -25,12 +25,16 @@ const (
 )
 
 // Errors introduced by this package.
+type Error struct {
+	os.ErrorString;
+}
+
 var (
-	PhaseError = os.NewError("phase error");
-	BufferFull = os.NewError("buffer full");
-	InternalError = os.NewError("bufio internal error");
-	BadBufSize = os.NewError("bad bufio size");
-	ShortWrite = os.NewError("short write");
+	PhaseError os.Error = &Error{"phase error"};
+	BufferFull os.Error = &Error{"buffer full"};
+	InternalError os.Error = &Error{"bufio internal error"};
+	BadBufSize os.Error = &Error{"bad bufio size"};
+	ShortWrite os.Error = &Error{"short write"};
 )
 
 func copySlice(dst []byte, src []byte) {
diff --git a/src/lib/http/request.go b/src/lib/http/request.go
index 3edaa4207..1173dd2a2 100644
--- a/src/lib/http/request.go
+++ b/src/lib/http/request.go
@@ -26,13 +26,16 @@ const (
 )
 
 // HTTP request parsing errors.
+type ProtocolError struct {
+	os.ErrorString
+}
 var (
-	LineTooLong = os.NewError("http header line too long");
-	ValueTooLong = os.NewError("http header value too long");
-	HeaderTooLong = os.NewError("http header too long");
-	BadHeader = os.NewError("malformed http header");
-	BadRequest = os.NewError("invalid http request");
-	BadHTTPVersion = os.NewError("unsupported http version");
+	LineTooLong = &ProtocolError{"http header line too long"};
+	ValueTooLong = &ProtocolError{"http header value too long"};
+	HeaderTooLong = &ProtocolError{"http header too long"};
+	BadHeader = &ProtocolError{"malformed http header"};
+	BadRequest = &ProtocolError{"invalid http request"};
+	BadHTTPVersion = &ProtocolError{"unsupported http version"};
 )
 
 // A Request represents a parsed HTTP request header.
diff --git a/src/lib/http/url.go b/src/lib/http/url.go
index 62699c13d..db51d99aa 100644
--- a/src/lib/http/url.go
+++ b/src/lib/http/url.go
@@ -13,9 +13,9 @@ import (
 )
 
 // Errors introduced by ParseURL.
-var (
-	BadURL = os.NewError("bad url syntax")
-)
+type BadURL struct {
+	os.ErrorString
+}
 
 func ishex(c byte) bool {
 	switch {
@@ -52,7 +52,7 @@ func URLUnescape(s string) (string, os.Error) {
 		if s[i] == '%' {
 			n++;
 			if !ishex(s[i+1]) || !ishex(s[i+2]) {
-				return "", BadURL;
+				return "", BadURL{"invalid hexadecimal escape"}
 			}
 			i += 3
 		} else {
@@ -110,7 +110,7 @@ func getscheme(rawurl string) (scheme, path string, err os.Error) {
 			}
 		case c == ':':
 			if i == 0 {
-				return "", "", BadURL
+				return "", "", BadURL{"missing protocol scheme"}
 			}
 			return rawurl[0:i], rawurl[i+1:len(rawurl)], nil
 		}
@@ -141,7 +141,7 @@ func split(s string, c byte, cutc bool) (string, string) {
 // (Web browsers strip #fragment before sending the URL to a web server.)
 func ParseURL(rawurl string) (url *URL, err os.Error) {
 	if rawurl == "" {
-		return nil, BadURL
+		return nil, BadURL{"empty url"}
 	}
 	url = new(URL);
 	url.Raw = rawurl;
diff --git a/src/lib/io/io.go b/src/lib/io/io.go
index bb6381099..b28359359 100644
--- a/src/lib/io/io.go
+++ b/src/lib/io/io.go
@@ -14,7 +14,10 @@ import (
 )
 
 // ErrEOF is the error returned by FullRead and Copyn when they encounter EOF.
-var ErrEOF = os.NewError("EOF")
+type Error struct {
+	os.ErrorString
+}
+var ErrEOF os.Error = &Error{"EOF"}
 
 // Reader is the interface that wraps the basic Read method.
 type Reader interface {
diff --git a/src/lib/net/Makefile b/src/lib/net/Makefile
index 3b6803740..efd6b3ef1 100644
--- a/src/lib/net/Makefile
+++ b/src/lib/net/Makefile
@@ -41,16 +41,16 @@ coverage: packages
 
 O1=\
 	dnsmsg.$O\
-	fd_$(GOOS).$O\
 	parse.$O\
 
 O2=\
-	fd.$O\
+	fd_$(GOOS).$O\
 	ip.$O\
 	port.$O\
 
 O3=\
 	dnsconfig.$O\
+	fd.$O\
 	net_$(GOOS).$O\
 
 O4=\
@@ -64,15 +64,15 @@ phases: a1 a2 a3 a4 a5
 _obj$D/net.a: phases
 
 a1: $(O1)
-	$(AR) grc _obj$D/net.a dnsmsg.$O fd_$(GOOS).$O parse.$O
+	$(AR) grc _obj$D/net.a dnsmsg.$O parse.$O
 	rm -f $(O1)
 
 a2: $(O2)
-	$(AR) grc _obj$D/net.a fd.$O ip.$O port.$O
+	$(AR) grc _obj$D/net.a fd_$(GOOS).$O ip.$O port.$O
 	rm -f $(O2)
 
 a3: $(O3)
-	$(AR) grc _obj$D/net.a dnsconfig.$O net_$(GOOS).$O
+	$(AR) grc _obj$D/net.a dnsconfig.$O fd.$O net_$(GOOS).$O
 	rm -f $(O3)
 
 a4: $(O4)
diff --git a/src/lib/net/dnsclient.go b/src/lib/net/dnsclient.go
index afae7cfb4..cfd67eabe 100644
--- a/src/lib/net/dnsclient.go
+++ b/src/lib/net/dnsclient.go
@@ -26,17 +26,20 @@ import (
 )
 
 // DNS errors returned by LookupHost.
+type DNSError struct {
+	os.ErrorString
+}
 var (
-	DNS_InternalError = os.NewError("internal dns error");
-	DNS_MissingConfig = os.NewError("no dns configuration");
-	DNS_No_Answer = os.NewError("dns got no answer");
-	DNS_BadRequest = os.NewError("malformed dns request");
-	DNS_BadReply = os.NewError("malformed dns reply");
-	DNS_ServerFailure = os.NewError("dns server failure");
-	DNS_NoServers = os.NewError("no dns servers");
-	DNS_NameTooLong = os.NewError("dns name too long");
-	DNS_RedirectLoop = os.NewError("dns redirect loop");
-	DNS_NameNotFound = os.NewError("dns name not found");
+	DNS_InternalError os.Error = &DNSError{"internal dns error"};
+	DNS_MissingConfig os.Error = &DNSError{"no dns configuration"};
+	DNS_No_Answer os.Error = &DNSError{"dns got no answer"};
+	DNS_BadRequest os.Error = &DNSError{"malformed dns request"};
+	DNS_BadReply os.Error = &DNSError{"malformed dns reply"};
+	DNS_ServerFailure os.Error = &DNSError{"dns server failure"};
+	DNS_NoServers os.Error = &DNSError{"no dns servers"};
+	DNS_NameTooLong os.Error = &DNSError{"dns name too long"};
+	DNS_RedirectLoop os.Error = &DNSError{"dns redirect loop"};
+	DNS_NameNotFound os.Error = &DNSError{"dns name not found"};
 )
 
 // Send a request on the connection and hope for a reply.
diff --git a/src/lib/net/fd_darwin.go b/src/lib/net/fd_darwin.go
index b4392d00e..cfc873fc9 100644
--- a/src/lib/net/fd_darwin.go
+++ b/src/lib/net/fd_darwin.go
@@ -12,6 +12,8 @@ import (
 	"syscall";
 )
 
+var kqueuePhaseError = &Error{"kqueue phase error"}
+
 type pollster struct {
 	kq int64;
 	eventbuf [10]syscall.Kevent_t;
@@ -54,7 +56,7 @@ func (p *pollster) AddFD(fd int64, mode int, repeat bool) os.Error {
 		return os.ErrnoToError(e)
 	}
 	if n != 1 || (ev.Flags & syscall.EV_ERROR) == 0 || ev.Ident != fd || ev.Filter != kmode {
-		return os.NewError("kqueue phase error")
+		return kqueuePhaseError
 	}
 	if ev.Data != 0 {
 		return os.ErrnoToError(ev.Data)
diff --git a/src/lib/net/net.go b/src/lib/net/net.go
index a95907e7f..cd2828592 100644
--- a/src/lib/net/net.go
+++ b/src/lib/net/net.go
@@ -12,11 +12,11 @@ import (
 )
 
 var (
-	BadAddress = os.NewError("malformed address");
-	MissingAddress = os.NewError("missing address");
-	UnknownNetwork = os.NewError("unknown network");
-	UnknownHost = os.NewError("unknown host");
-	UnknownSocketFamily = os.NewError("unknown socket family");
+	BadAddress os.Error = &Error{"malformed address"};
+	MissingAddress os.Error = &Error{"missing address"};
+	UnknownNetwork os.Error = &Error{"unknown network"};
+	UnknownHost os.Error = &Error{"unknown host"};
+	UnknownSocketFamily os.Error = &Error{"unknown socket family"};
 )
 
 
diff --git a/src/lib/net/parse.go b/src/lib/net/parse.go
index 78eff5f47..de47cb812 100644
--- a/src/lib/net/parse.go
+++ b/src/lib/net/parse.go
@@ -12,6 +12,10 @@ import (
 	"os";
 )
 
+type Error struct {
+	os.ErrorString
+}
+
 type file struct {
 	file *os.File;
 	data []byte;
diff --git a/src/lib/net/port.go b/src/lib/net/port.go
index 073af658a..21e3b48aa 100644
--- a/src/lib/net/port.go
+++ b/src/lib/net/port.go
@@ -16,7 +16,7 @@ import (
 
 // The error returned by LookupPort when a network service
 // is not listed in the database.
-var ErrNoService = os.NewError("unknown network service");
+var ErrNoService = &Error{"unknown network service"};
 
 var services map[string] map[string] int
 var servicesError os.Error
diff --git a/src/lib/os/error.go b/src/lib/os/error.go
index 5acefd2ad..3861f0167 100644
--- a/src/lib/os/error.go
+++ b/src/lib/os/error.go
@@ -18,6 +18,11 @@ func (e ErrorString) String() string {
 	return e
 }
 
+// NewError converts s to an ErrorString, which satisfies the Error interface.
+func NewError(s string) Error {
+	return ErrorString(s)
+}
+
 // Errno is the Unix error number.  Names such as EINVAL are simple
 // wrappers to convert the error number into an Error.
 type Errno int64
@@ -74,48 +79,3 @@ var (
 	ERANGE Error = Errno(syscall.ERANGE);
 )
 
-// -----------------------
-// Everything below here is deprecated.
-// Delete when all callers of NewError are gone and their uses converted
-// to the new error scheme (for an example, see template).
-
-// _Error is a structure wrapping a string describing an error.
-// Errors are singleton structures, created by NewError, so their addresses can
-// be compared to test for equality. A nil Error pointer means ``no error''.
-// Use the String() method to get the contents; it handles the nil case.
-// The Error type is intended for use by any package that wishes to define
-// error strings.
-type _Error struct {
-	s string
-}
-
-// Table of all known errors in system.  Use the same error string twice,
-// get the same *os._Error.
-var errorStringTab = make(map[string] Error);
-
-// These functions contain a race if two goroutines add identical
-// errors simultaneously but the consequences are unimportant.
-
-// NewError allocates an Error object, but if s has been seen before,
-// shares the _Error associated with that message.
-func NewError(s string) Error {
-	if s == "" {
-		return nil
-	}
-	err, ok := errorStringTab[s];
-	if ok {
-		return err
-	}
-	err = &_Error{s};
-	errorStringTab[s] = err;
-	return err;
-}
-
-
-// String returns the string associated with the _Error.
-func (e *_Error) String() string {
-	if e == nil {
-		return "No _Error"
-	}
-	return e.s
-}