[gjs/wip/ptomato/mozjs38: 16/17] WIP - Latin1 vs UTF-16 strings

[Philip Chimento <pchimento src gnome org>]

commit 41ed408bc65d6f5b4fb2d64191cf6cfd33be1c93
Author: Philip Chimento <philip chimento gmail com>
Date:   Tue Jan 17 23:36:07 2017 -0800

    WIP - Latin1 vs UTF-16 strings
    
    Strings can be stored in one of two formats now, so we need to deal with
    both when getting their characters.

 gjs/byteArray.cpp         |   45 ++++++++++++++++++++++++++++++---------------
 gjs/jsapi-util-string.cpp |   11 +++++++++--
 gjs/jsapi-util.cpp        |    3 ++-
 3 files changed, 41 insertions(+), 18 deletions(-)
---
diff --git a/gjs/byteArray.cpp b/gjs/byteArray.cpp
index 2809abd..b441f2d 100644
--- a/gjs/byteArray.cpp
+++ b/gjs/byteArray.cpp
@@ -603,24 +603,39 @@ from_string_func(JSContext *context,
         g_byte_array_append(priv->array, (guint8*) utf8, strlen(utf8));
         g_free(utf8);
     } else {
-        char *encoded;
+        JSString *str = argv[0].toString();  /* Rooted by argv */
+        GError *error = NULL;
+        char *encoded = NULL;
         gsize bytes_written;
-        GError *error;
-        const char16_t *u16_chars;
-        gsize u16_len;
 
-        u16_chars = JS_GetStringCharsAndLength(context, argv[0].toString(), &u16_len);
-        if (u16_chars == NULL)
-            return false;
+        {
+            size_t len;
+            JS::AutoCheckCannotGC nogc;
+            if (JS_StringHasLatin1Chars(str)) {
+                const JS::Latin1Char *chars =
+                    JS_GetLatin1StringCharsAndLength(context, nogc, str, &len);
+                if (chars == NULL)
+                    return false;
+
+                encoded = g_convert((char *) chars, len,
+                                    encoding,  /* to_encoding */
+                                    "LATIN1",  /* from_encoding */
+                                    NULL,  /* bytes read */
+                                    &bytes_written, &error);
+            } else {
+                const char16_t *chars =
+                    JS_GetTwoByteStringCharsAndLength(context, nogc, str, &len);
+                if (chars == NULL)
+                    return false;
+
+                encoded = g_convert((char *) chars, len * 2,
+                                    encoding,  /* to_encoding */
+                                    "UTF-16",  /* from_encoding */
+                                    NULL,  /* bytes read */
+                                    &bytes_written, &error);
+            }
+        }
 
-        error = NULL;
-        encoded = g_convert((char*) u16_chars,
-                            u16_len * 2,
-                            encoding, /* to_encoding */
-                            "UTF-16", /* from_encoding */
-                            NULL, /* bytes read */
-                            &bytes_written,
-                            &error);
         g_free(encoding);
         if (encoded == NULL) {
             /* frees the GError */
diff --git a/gjs/jsapi-util-string.cpp b/gjs/jsapi-util-string.cpp
index 6143b47..509413f 100644
--- a/gjs/jsapi-util-string.cpp
+++ b/gjs/jsapi-util-string.cpp
@@ -191,7 +191,12 @@ gjs_string_get_char16_data(JSContext       *context,
         goto out;
     }
 
-    js_data = JS_GetStringCharsAndLength(context, value.toString(), len_p);
+    /* Scope for nogc */
+    {
+        JS::AutoCheckCannotGC nogc;
+        js_data = JS_GetTwoByteStringCharsAndLength(context, nogc,
+                                                    value.toString(), len_p);
+    }
     if (js_data == NULL)
         goto out;
 
@@ -231,7 +236,9 @@ gjs_string_to_ucs4(JSContext      *cx,
     size_t utf16_len;
     GError *error = NULL;
 
-    const char16_t *utf16 = JS_GetStringCharsAndLength(cx, str, &utf16_len);
+    JS::AutoCheckCannotGC nogc;
+    const char16_t *utf16 = JS_GetTwoByteStringCharsAndLength(cx, nogc, str,
+                                                              &utf16_len);
     if (utf16 == NULL) {
         gjs_throw(cx, "Failed to get UTF-16 string data");
         return false;
diff --git a/gjs/jsapi-util.cpp b/gjs/jsapi-util.cpp
index 417e4af..f8989f8 100644
--- a/gjs/jsapi-util.cpp
+++ b/gjs/jsapi-util.cpp
@@ -378,7 +378,8 @@ gjs_string_readable (JSContext   *context,
         size_t i, len;
         const char16_t *uchars;
 
-        uchars = JS_GetStringCharsAndLength(context, string, &len);
+        JS::AutoCheckCannotGC nogc;
+        uchars = JS_GetTwoByteStringCharsAndLength(context, nogc, string, &len);
 
         for (i = 0; i < len; i++) {
             char16_t c = uchars[i];