From b3de605d50bfcbeedd6df70931594522f9738fdc Mon Sep 17 00:00:00 2001
From: Pietro Gagliardi <pietro10@mac.com>
Date: Wed, 8 Aug 2018 21:31:12 -0400
Subject: [PATCH] Started template support, writing the initial C++ template.

---
 windows/tools/a              | 11 ---------
 windows/tools/cpp.template   | 29 +++++++++++++++++++++++
 windows/tools/gen.sh         |  2 +-
 windows/tools/hresultwrap.go | 46 +++++++++++++++++++++++++++++++++---
 4 files changed, 73 insertions(+), 15 deletions(-)
 create mode 100644 windows/tools/cpp.template

diff --git a/windows/tools/a b/windows/tools/a
index 7f6648df..5be22d75 100644
--- a/windows/tools/a
+++ b/windows/tools/a
@@ -1,14 +1,3 @@
-static HRESULT lastErrorToHRESULT(DWORD lasterr, const char *funcname)
-{
-	HRESULT hr;
-
-	hr = E_FAIL;
-	if (lasterr != 0)
-		hr = HRESULT_FROM_WIN32(lasterr);
-	uiprivImplBug("error calling %s: last error %I32d\n", funcname, lasterr);
-	return hr;
-}
-
 @BOOL GetWindowPlacement HWND hwnd uiprivLPWWINDOWPLACEMENT wp == 0
 $typedef const WINDOWPLACEMENT *uiprivLPCWINDOWPLACEMENT;
 @BOOL SetWindowPlacement HWND hwnd uiprivLPCWINDOWPLACEMENT wp == 0
diff --git a/windows/tools/cpp.template b/windows/tools/cpp.template
new file mode 100644
index 00000000..ced37e58
--- /dev/null
+++ b/windows/tools/cpp.template
@@ -0,0 +1,29 @@
+{{/* 8 august 2018 */}}// this file is generated by tools/hresultwrap and should NOT be modified directly
+#include "uipriv_windows.hpp"
+
+static inline HRESULT lastErrorToHRESULT(DWORD lasterr, const char *funcname)
+{
+	HRESULT hr;
+
+	hr = E_FAIL;
+	if (lasterr != 0)
+		hr = HRESULT_FROM_WIN32(lasterr);
+	uiprivImplBug("error calling %s: last error %I32d\n", funcname, lasterr);
+	return hr;
+}{{range .}}
+
+{{$narg := len .Arg}}HRESULT {{if .CallingConvention}}{{.CallingConvention}}{{else}}WINAPI{{end}} uiprivHR{{.Name}}({{range $i, $a := .Arg}}{{$a}}{{argcomma $i $narg}}{{end}}{{if .Save}}, _Out_ {{.Ret}} *outRet{{end}})
+{
+	{{.Ret}} xyzret;
+	DWORD xyzlasterr;
+
+{{if .Save}}	if (outRet == NULL)
+		return E_POINTER;
+{{end}}	SetLastError(0);
+	xyzret = {{.Name}}({{range $i, $a := .Arg}}{{argname $a}}{{argcomma $i $narg}}{{end}});
+	xyzlasterr = GetLastError();
+{{if .Save}}	*outRet = xyzret;
+{{end}}	if (xyzret != {{.Failval}})
+		return S_OK;
+	return lastErrToHRESULT(xyzlasterr, "{{.Name}}()");
+}{{end}}
diff --git a/windows/tools/gen.sh b/windows/tools/gen.sh
index 7f39837f..168df8fa 100755
--- a/windows/tools/gen.sh
+++ b/windows/tools/gen.sh
@@ -1 +1 @@
-./hresultwrap funclist.textpb
+./hresultwrap funclist.textpb cpp.template
diff --git a/windows/tools/hresultwrap.go b/windows/tools/hresultwrap.go
index b806cd9f..edf9e6b2 100644
--- a/windows/tools/hresultwrap.go
+++ b/windows/tools/hresultwrap.go
@@ -6,13 +6,43 @@ import (
 	"fmt"
 	"os"
 	"io/ioutil"
+	"text/template"
+	"strings"
 
 	"github.com/golang/protobuf/proto"
 )
 
+func argname(arg string) string {
+	fields := strings.Fields(arg)
+	last := fields[len(fields) - 1]
+	start := strings.LastIndexFunc(last, func(r rune) bool {
+		return !(r >= 'A' && r <= 'Z') &&
+			!(r >= 'a' && r <= 'z') &&
+			!(r >= '0' && r <= '9') &&
+			r != '_'
+	})
+	if start == -1 {
+		return last
+	}
+	// TODO replace + 1 with + len of that last rune
+	return last[start + 1:]
+}
+
+func argcomma(n, len int) string {
+	if n == len - 1 {
+		return ""
+	}
+	return ", "
+}
+
+var templateFuncs = template.FuncMap{
+	"argname":	argname,
+	"argcomma":	argcomma,
+}
+
 func main() {
-	if len(os.Args) != 2 {
-		fmt.Fprintf(os.Stderr, "usage: %s funclist\n", os.Args[0])
+	if len(os.Args) != 3 {
+		fmt.Fprintf(os.Stderr, "usage: %s funclist template\n", os.Args[0])
 		os.Exit(1)
 	}
 	b, err := ioutil.ReadFile(os.Args[1])
@@ -26,5 +56,15 @@ func main() {
 		fmt.Fprintf(os.Stderr, "error parsing %s: %v\n", os.Args[1], err)
 		os.Exit(1)
 	}
-	fmt.Println(f)
+
+	tmpl, err := template.New(os.Args[2]).Funcs(templateFuncs).ParseFiles(os.Args[2])
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "error parsing %s: %v\n", os.Args[2], err)
+		os.Exit(1)
+	}
+	err = tmpl.Execute(os.Stdout, f.Func)
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "error executing template: %v\n", err)
+		os.Exit(1)
+	}
 }