js/src/xpconnect/loader/mozJSSubScriptLoader.cpp

   1 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*-
   2  * vim: set ts=4 sw=4 et tw=80:
   3  *
   4  * ***** BEGIN LICENSE BLOCK *****
   5  * Version: MPL 1.1/GPL 2.0/LGPL 2.1
   6  *
   7  * The contents of this file are subject to the Mozilla Public License Version
   8  * 1.1 (the "License"); you may not use this file except in compliance with
   9  * the License. You may obtain a copy of the License at
  10  * http://www.mozilla.org/MPL/
  11  *
  12  * Software distributed under the License is distributed on an "AS IS" basis,
  13  * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
  14  * for the specific language governing rights and limitations under the
  15  * License.
  16  *
  17  * The Original Code is Mozilla Communicator client code, released
  18  * March 31, 1998.
  19  *
  20  * The Initial Developer of the Original Code is
  21  * Netscape Communications Corporation.
  22  * Portions created by the Initial Developer are Copyright (C) 1998
  23  * the Initial Developer. All Rights Reserved.
  24  *
  25  * Contributor(s):
  26  *   Robert Ginda <rginda@netscape.com>
  27  *
  28  * Alternatively, the contents of this file may be used under the terms of
  29  * either of the GNU General Public License Version 2 or later (the "GPL"),
  30  * or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
  31  * in which case the provisions of the GPL or the LGPL are applicable instead
  32  * of those above. If you wish to allow use of your version of this file only
  33  * under the terms of either the GPL or the LGPL, and not to allow others to
  34  * use your version of this file under the terms of the MPL, indicate your
  35  * decision by deleting the provisions above and replace them with the notice
  36  * and other provisions required by the GPL or the LGPL. If you do not delete
  37  * the provisions above, a recipient may use your version of this file under
  38  * the terms of any one of the MPL, the GPL or the LGPL.
  39  *
  40  * ***** END LICENSE BLOCK ***** */
  41
  42 #if !defined(XPCONNECT_STANDALONE) && !defined(NO_SUBSCRIPT_LOADER)
  43
  44 #include "mozJSSubScriptLoader.h"
  45
  46 #include "nsIServiceManager.h"
  47 #include "nsIXPConnect.h"
  48
  49 #include "nsIURI.h"
  50 #include "nsIIOService.h"
  51 #include "nsIChannel.h"
  52 #include "nsIInputStream.h"
  53 #include "nsNetCID.h"
  54 #include "nsDependentString.h"
  55 #include "nsAutoPtr.h"
  56 #include "nsNetUtil.h"
  57 #include "nsIProtocolHandler.h"
  58 #include "nsIFileURL.h"
  59
  60 #include "jsapi.h"
  61 #include "jsdbgapi.h"
  62 #include "jsobj.h"
  63
  64 #include "mozilla/FunctionTimer.h"
  65
  66 /* load() error msgs, XXX localize? */
  67 #define LOAD_ERROR_NOSERVICE "Error creating IO Service."
  68 #define LOAD_ERROR_NOURI "Error creating URI (invalid URL scheme?)"
  69 #define LOAD_ERROR_NOSCHEME "Failed to get URI scheme.  This is bad."
  70 #define LOAD_ERROR_URI_NOT_LOCAL "Trying to load a non-local URI."
  71 #define LOAD_ERROR_NOSTREAM  "Error opening input stream (invalid filename?)"
  72 #define LOAD_ERROR_NOCONTENT "ContentLength not available (not a local URL?)"
  73 #define LOAD_ERROR_BADREAD   "File Read Error."
  74 #define LOAD_ERROR_READUNDERFLOW "File Read Error (underflow.)"
  75 #define LOAD_ERROR_NOPRINCIPALS "Failed to get principals."
  76 #define LOAD_ERROR_NOSPEC "Failed to get URI spec.  This is bad."
  77
  78 // We just use the same reporter as the component loader
  79 extern void
  80 mozJSLoaderErrorReporter(JSContext *cx, const char *message, JSErrorReport *rep);
  81
  82 mozJSSubScriptLoader::mozJSSubScriptLoader() : mSystemPrincipal(nsnull)
  83 {
  84 }
  85
  86 mozJSSubScriptLoader::~mozJSSubScriptLoader()
  87 {
  88     /* empty */
  89 }
  90
  91 NS_IMPL_THREADSAFE_ISUPPORTS1(mozJSSubScriptLoader, mozIJSSubScriptLoader)
  92
  93 NS_IMETHODIMP /* args and return value are delt with using XPConnect and JSAPI */
  94 mozJSSubScriptLoader::LoadSubScript (const PRUnichar * aURL
  95                                      /* [, JSObject *target_obj] */)
  96 {
  97     /*
  98      * Loads a local url and evals it into the current cx
  99      * Synchronous (an async version would be cool too.)
 100      *   url: The url to load.  Must be local so that it can be loaded
 101      *        synchronously.
 102      *   target_obj: Optional object to eval the script onto (defaults to context
 103      *               global)
 104      *   returns: Whatever jsval the script pointed to by the url returns.
 105      * Should ONLY (O N L Y !) be called from JavaScript code.
 106      */
 107
 108     /* gotta define most of this stuff up here because of all the gotos,
 109      * defined the rest up here to be consistent */
 110     nsresult  rv;
 111     JSBool    ok;
 112
 113 #ifdef NS_FUNCTION_TIMER
 114     NS_TIME_FUNCTION_FMT("%s (line %d) (url: %s)", MOZ_FUNCTION_NAME,
 115                          __LINE__, NS_LossyConvertUTF16toASCII(aURL).get());
 116 #else
 117     (void)aURL; // prevent compiler warning
 118 #endif
 119
 120     /* get JS things from the CallContext */
 121     nsCOMPtr<nsIXPConnect> xpc = do_GetService(nsIXPConnect::GetCID());
 122     if (!xpc) return NS_ERROR_FAILURE;
 123
 124     nsAXPCNativeCallContext *cc = nsnull;
 125     rv = xpc->GetCurrentNativeCallContext(&cc);
 126     if (NS_FAILED(rv)) return NS_ERROR_FAILURE;
 127
 128     JSContext *cx;
 129     rv = cc->GetJSContext (&cx);
 130     if (NS_FAILED(rv)) return NS_ERROR_FAILURE;
 131
 132     PRUint32 argc;
 133     rv = cc->GetArgc (&argc);
 134     if (NS_FAILED(rv)) return NS_ERROR_FAILURE;
 135
 136     jsval *argv;
 137     rv = cc->GetArgvPtr (&argv);
 138     if (NS_FAILED(rv)) return NS_ERROR_FAILURE;
 139
 140     jsval *rval;
 141     rv = cc->GetRetValPtr (&rval);
 142     if (NS_FAILED(rv)) return NS_ERROR_FAILURE;
 143
 144     /* set mJSPrincipals if it's not here already */
 145     if (!mSystemPrincipal)
 146     {
 147         nsCOMPtr<nsIScriptSecurityManager> secman =
 148             do_GetService(NS_SCRIPTSECURITYMANAGER_CONTRACTID);
 149         if (!secman)
 150             return rv;
 151
 152         rv = secman->GetSystemPrincipal(getter_AddRefs(mSystemPrincipal));
 153         if (NS_FAILED(rv) || !mSystemPrincipal)
 154             return rv;
 155     }
 156
 157     JSAutoRequest ar(cx);
 158
 159     char     *url;
 160     JSObject *target_obj = nsnull;
 161     ok = JS_ConvertArguments (cx, argc, argv, "s / o", &url, &target_obj);
 162     if (!ok)
 163     {
 164         /* let the exception raised by JS_ConvertArguments show through */
 165         return NS_OK;
 166     }
 167
 168     if (!target_obj)
 169     {
 170         /* if the user didn't provide an object to eval onto, find the global
 171          * object by walking the parent chain of the calling object */
 172
 173 #ifdef DEBUG_rginda
 174         JSObject *got_glob = JS_GetGlobalObject (cx);
 175         fprintf (stderr, "JS_GetGlobalObject says glob is %p.\n", got_glob);
 176         target_obj = JS_GetPrototype (cx, got_glob);
 177         fprintf (stderr, "That glob's prototype is %p.\n", target_obj);
 178         target_obj = JS_GetParent (cx, got_glob);
 179         fprintf (stderr, "That glob's parent is %p.\n", target_obj);
 180 #endif
 181
 182         nsCOMPtr<nsIXPConnectWrappedNative> wn;
 183         rv = cc->GetCalleeWrapper (getter_AddRefs(wn));
 184         if (NS_FAILED(rv)) return NS_ERROR_FAILURE;
 185
 186         rv = wn->GetJSObject (&target_obj);
 187         if (NS_FAILED(rv)) return NS_ERROR_FAILURE;
 188
 189 #ifdef DEBUG_rginda
 190         fprintf (stderr, "Parent chain: %p", target_obj);
 191 #endif
 192         JSObject *maybe_glob = JS_GetParent (cx, target_obj);
 193         while (maybe_glob != nsnull)
 194         {
 195 #ifdef DEBUG_rginda
 196             fprintf (stderr, ", %p", maybe_glob);
 197 #endif
 198             target_obj = maybe_glob;
 199             maybe_glob = JS_GetParent (cx, maybe_glob);
 200         }
 201 #ifdef DEBUG_rginda
 202         fprintf (stderr, "\n");
 203 #endif
 204     }
 205
 206     // Innerize the target_obj so that we compile the loaded script in the
 207     // correct (inner) scope.
 208     if (JSObjectOp op = target_obj->getClass()->ext.innerObject)
 209     {
 210         target_obj = op(cx, target_obj);
 211         if (!target_obj) return NS_ERROR_FAILURE;
 212 #ifdef DEBUG_rginda
 213         fprintf (stderr, "Final global: %p\n", target_obj);
 214 #endif
 215     }
 216
 217     /* load up the url.  From here on, failures are reflected as ``custom''
 218      * js exceptions */
 219     PRInt32   len = -1;
 220     PRUint32  readcount = 0;  // Total amount of data read
 221     PRUint32  lastReadCount = 0;  // Amount of data read in last Read() call
 222     nsAutoArrayPtr<char> buf;
 223
 224     JSString        *errmsg;
 225     JSErrorReporter  er;
 226     JSPrincipals    *jsPrincipals;
 227
 228     nsCOMPtr<nsIChannel>     chan;
 229     nsCOMPtr<nsIInputStream> instream;
 230     nsCOMPtr<nsIURI> uri;
 231     nsCAutoString uriStr;
 232     nsCAutoString scheme;
 233
 234     JSStackFrame* frame = nsnull;
 235     JSScript* script = nsnull;
 236
 237     // Figure out who's calling us
 238     do
 239     {
 240         frame = JS_FrameIterator(cx, &frame);
 241
 242         if (frame)
 243             script = JS_GetFrameScript(cx, frame);
 244     } while (frame && !script);
 245
 246     if (!script)
 247     {
 248         // No script means we don't know who's calling, bail.
 249
 250         return NS_ERROR_FAILURE;
 251     }
 252
 253     nsCOMPtr<nsIIOService> serv = do_GetService(NS_IOSERVICE_CONTRACTID);
 254     if (!serv)
 255     {
 256         errmsg = JS_NewStringCopyZ (cx, LOAD_ERROR_NOSERVICE);
 257         goto return_exception;
 258     }
 259
 260     // Make sure to explicitly create the URI, since we'll need the
 261     // canonicalized spec.
 262     rv = NS_NewURI(getter_AddRefs(uri), url, nsnull, serv);
 263     if (NS_FAILED(rv)) {
 264         errmsg = JS_NewStringCopyZ (cx, LOAD_ERROR_NOURI);
 265         goto return_exception;
 266     }
 267
 268     rv = uri->GetSpec(uriStr);
 269     if (NS_FAILED(rv)) {
 270         errmsg = JS_NewStringCopyZ (cx, LOAD_ERROR_NOSPEC);
 271         goto return_exception;
 272     }
 273
 274     rv = uri->GetScheme(scheme);
 275     if (NS_FAILED(rv))
 276     {
 277         errmsg = JS_NewStringCopyZ (cx, LOAD_ERROR_NOSCHEME);
 278         goto return_exception;
 279     }
 280
 281     if (!scheme.EqualsLiteral("chrome"))
 282     {
 283         // This might be a URI to a local file, though!
 284         nsCOMPtr<nsIURI> innerURI = NS_GetInnermostURI(uri);
 285         nsCOMPtr<nsIFileURL> fileURL = do_QueryInterface(innerURI);
 286         if (!fileURL)
 287         {
 288             errmsg = JS_NewStringCopyZ (cx, LOAD_ERROR_URI_NOT_LOCAL);
 289             goto return_exception;
 290         }
 291
 292         // For file URIs prepend the filename with the filename of the
 293         // calling script, and " -> ". See bug 418356.
 294         nsCAutoString tmp(JS_GetScriptFilename(cx, script));
 295         tmp.AppendLiteral(" -> ");
 296         tmp.Append(uriStr);
 297
 298         uriStr = tmp;
 299     }
 300
 301     rv = NS_OpenURI(getter_AddRefs(instream), uri, serv,
 302                     nsnull, nsnull, nsIRequest::LOAD_NORMAL,
 303                     getter_AddRefs(chan));
 304     if (NS_FAILED(rv))
 305     {
 306         errmsg = JS_NewStringCopyZ (cx, LOAD_ERROR_NOSTREAM);
 307         goto return_exception;
 308     }
 309
 310     rv = chan->GetContentLength (&len);
 311     if (NS_FAILED(rv) || len == -1)
 312     {
 313         errmsg = JS_NewStringCopyZ (cx, LOAD_ERROR_NOCONTENT);
 314         goto return_exception;
 315     }
 316
 317     buf = new char[len + 1];
 318     if (!buf)
 319         return NS_ERROR_OUT_OF_MEMORY;
 320     buf[len] = '\0';
 321
 322     do {
 323         rv = instream->Read (buf + readcount, len - readcount, &lastReadCount);
 324         if (NS_FAILED(rv))
 325         {
 326             errmsg = JS_NewStringCopyZ (cx, LOAD_ERROR_BADREAD);
 327             goto return_exception;
 328         }
 329         readcount += lastReadCount;
 330     } while (lastReadCount && readcount != PRUint32(len));
 331
 332     if (static_cast<PRUint32>(len) != readcount)
 333     {
 334         errmsg = JS_NewStringCopyZ (cx, LOAD_ERROR_READUNDERFLOW);
 335         goto return_exception;
 336     }
 337
 338     /* we can't hold onto jsPrincipals as a module var because the
 339      * JSPRINCIPALS_DROP macro takes a JSContext, which we won't have in the
 340      * destructor */
 341     rv = mSystemPrincipal->GetJSPrincipals(cx, &jsPrincipals);
 342     if (NS_FAILED(rv) || !jsPrincipals) {
 343         errmsg = JS_NewStringCopyZ (cx, LOAD_ERROR_NOPRINCIPALS);
 344         goto return_exception;
 345     }
 346
 347     /* set our own error reporter so we can report any bad things as catchable
 348      * exceptions, including the source/line number */
 349     er = JS_SetErrorReporter (cx, mozJSLoaderErrorReporter);
 350
 351     ok = JS_EvaluateScriptForPrincipals (cx, target_obj, jsPrincipals,
 352                                          buf, len, uriStr.get(), 1, rval);
 353     /* repent for our evil deeds */
 354     JS_SetErrorReporter (cx, er);
 355
 356     cc->SetReturnValueWasSet (ok);
 357
 358     JSPRINCIPALS_DROP(cx, jsPrincipals);
 359     return NS_OK;
 360
 361  return_exception:
 362     JS_SetPendingException (cx, STRING_TO_JSVAL(errmsg));
 363     return NS_OK;
 364 }
 365
 366 #endif /* NO_SUBSCRIPT_LOADER */