michael@0: /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: /*
michael@0: 
michael@0:   Implementations for a bunch of useful RDF utility routines.  Many of
michael@0:   these will eventually be exported outside of RDF.DLL via the
michael@0:   nsIRDFService interface.
michael@0: 
michael@0:   TO DO
michael@0: 
michael@0:   1) Make this so that it doesn't permanently leak the RDF service
michael@0:      object.
michael@0: 
michael@0:   2) Make container functions thread-safe. They currently don't ensure
michael@0:      that the RDF:nextVal property is maintained safely.
michael@0: 
michael@0:  */
michael@0: 
michael@0: #include "nsCOMPtr.h"
michael@0: #include "nsIRDFDataSource.h"
michael@0: #include "nsIRDFNode.h"
michael@0: #include "nsIRDFService.h"
michael@0: #include "nsIServiceManager.h"
michael@0: #include "nsIURL.h"
michael@0: #include "nsIIOService.h"
michael@0: #include "nsIURL.h"
michael@0: #include "nsNetUtil.h"
michael@0: #include "nsRDFCID.h"
michael@0: #include "nsString.h"
michael@0: #include "nsXPIDLString.h"
michael@0: #include "nsUnicharUtils.h"
michael@0: #include "rdfutil.h"
michael@0: 
michael@0: ////////////////////////////////////////////////////////////////////////
michael@0: 
michael@0: nsresult
michael@0: rdf_MakeRelativeRef(const nsCSubstring& aBaseURI, nsCString& aURI)
michael@0: {
michael@0:     // This implementation is extremely simple: e.g., it can't compute
michael@0:     // relative paths, or anything fancy like that. If the context URI
michael@0:     // is not a prefix of the URI in question, we'll just bail.
michael@0:     uint32_t prefixLen = aBaseURI.Length();
michael@0:     if (prefixLen != 0 && StringBeginsWith(aURI, aBaseURI)) {
michael@0:         if (prefixLen < aURI.Length() && aURI.CharAt(prefixLen) == '/')
michael@0:             ++prefixLen; // chop the leading slash so it's not `absolute'
michael@0: 
michael@0:         aURI.Cut(0, prefixLen);
michael@0:     }
michael@0: 
michael@0:     return NS_OK;
michael@0: }
michael@0: 
michael@0: void
michael@0: rdf_FormatDate(PRTime aTime, nsACString &aResult)
michael@0: {
michael@0:     // Outputs Unixish date in GMT plus usecs; e.g.,
michael@0:     //   Wed Jan  9 19:15:13 2002 +002441
michael@0:     //
michael@0:     PRExplodedTime t;
michael@0:     PR_ExplodeTime(aTime, PR_GMTParameters, &t);
michael@0: 
michael@0:     char buf[256];
michael@0:     PR_FormatTimeUSEnglish(buf, sizeof buf, "%a %b %d %H:%M:%S %Y", &t);
michael@0:     aResult.Append(buf);
michael@0: 
michael@0:     // usecs
michael@0:     aResult.Append(" +");
michael@0:     int32_t usec = t.tm_usec;
michael@0:     for (int32_t digit = 100000; digit > 1; digit /= 10) {
michael@0:         aResult.Append(char('0' + (usec / digit)));
michael@0:         usec %= digit;
michael@0:     }
michael@0:     aResult.Append(char('0' + usec));
michael@0: }
michael@0: 
michael@0: PRTime
michael@0: rdf_ParseDate(const nsACString &aTime)
michael@0: {
michael@0:     PRTime t;
michael@0:     PR_ParseTimeString(PromiseFlatCString(aTime).get(), true, &t);
michael@0: 
michael@0:     int32_t usec = 0;
michael@0: 
michael@0:     nsACString::const_iterator begin, digit, end;
michael@0:     aTime.BeginReading(begin);
michael@0:     aTime.EndReading(end);
michael@0: 
michael@0:     // Walk backwards until we find a `+', run out of string, or a
michael@0:     // non-numeric character.
michael@0:     digit = end;
michael@0:     while (--digit != begin && *digit != '+') {
michael@0:         if (*digit < '0' || *digit > '9')
michael@0:             break;
michael@0:     }
michael@0: 
michael@0:     if (digit != begin && *digit == '+') {
michael@0:         // There's a usec field specified (or, at least, something
michael@0:         // that looks close enough. Parse it, and add it to the time.
michael@0:         while (++digit != end) {
michael@0:             usec *= 10;
michael@0:             usec += *digit - '0';
michael@0:         }
michael@0: 
michael@0:         t += usec;
michael@0:     }
michael@0: 
michael@0:     return t;
michael@0: }