Patchwork [v9,2/4] qemu: URI parsing library

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Submitter Bharata B Rao
Date Sept. 24, 2012, 9:12 a.m.
Message ID <20120924091202.GL18470@in.ibm.com>
Download mbox | patch
Permalink /patch/186332/
State New
Headers show

Comments

Bharata B Rao - Sept. 24, 2012, 9:12 a.m.
qemu: URI parsing library

From: Paolo Bonzini <pbonzini@redhat.com>

Add a new URI parsing library to QEMU. The code has been borrowed from
libxml2 and libvirt.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Bharata B Rao <bharata@linux.vnet.ibm.com>
---

 Makefile.objs |    2 
 uri.c         | 2249 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 uri.h         |  113 +++
 3 files changed, 2363 insertions(+), 1 deletions(-)
 create mode 100644 uri.c
 create mode 100644 uri.h
Richard W.M. Jones - Sept. 24, 2012, 10:27 a.m.
On Mon, Sep 24, 2012 at 02:42:02PM +0530, Bharata B Rao wrote:
> qemu: URI parsing library
> 
> From: Paolo Bonzini <pbonzini@redhat.com>
> 
> Add a new URI parsing library to QEMU. The code has been borrowed from
> libxml2 and libvirt.

Rather than duplicating the libxml2 code, I think it would be better
to depend on libxml2.  While it's not ideal to add more external
dependencies, libxml2 is very commonly available.  Also libxml2 gets
frequent security updates and you never know when the URI code here
might be found to contain some sort of bug / security issue.

This will need a change to the qemu configure script of course.

Rich.
Paolo Bonzini - Sept. 24, 2012, 11:11 a.m.
----- Messaggio originale -----
> Da: "Richard W.M. Jones" <rjones@redhat.com>
> A: "Bharata B Rao" <bharata@linux.vnet.ibm.com>
> Cc: qemu-devel@nongnu.org, "Paolo Bonzini" <pbonzini@redhat.com>, "Kevin Wolf" <kwolf@redhat.com>, "Avi Kivity"
> <avi@redhat.com>, "Anthony Liguori" <aliguori@us.ibm.com>, "Stefan Hajnoczi" <stefanha@gmail.com>, "Blue Swirl"
> <blauwirbel@gmail.com>, "Anand Avati" <aavati@redhat.com>, "Vijay Bellur" <vbellur@redhat.com>, "Amar Tumballi"
> <amarts@redhat.com>, "Harsh Bora" <harsh@linux.vnet.ibm.com>, "Daniel Veillard" <veillard@redhat.com>
> Inviato: Lunedì, 24 settembre 2012 12:27:38
> Oggetto: Re: [PATCH v9 2/4] qemu: URI parsing library
> 
> 
> On Mon, Sep 24, 2012 at 02:42:02PM +0530, Bharata B Rao wrote:
> > qemu: URI parsing library
> > 
> > From: Paolo Bonzini <pbonzini@redhat.com>
> > 
> > Add a new URI parsing library to QEMU. The code has been borrowed
> > from libxml2 and libvirt.
> 
> Rather than duplicating the libxml2 code, I think it would be better
> to depend on libxml2.  While it's not ideal to add more external
> dependencies, libxml2 is very commonly available.  Also libxml2 gets
> frequent security updates and you never know when the URI code here
> might be found to contain some sort of bug / security issue.

You're preaching to the choir here, but I think there are limited
advantages in this case.  The URI parsing has seen hardly any change
in the last 2 years and is surprisingly self-contained even in libxml2:
the dependencies were limited to memory allocation hooks basically.

A better plan would be to incorporate this code into glib, completing
the extremely sparse URI support that is already there.  However, we
would not be able to use it anyway, because we support compiling on old
glib versions.

Paolo

> This will need a change to the qemu configure script of course.
> 
> Rich.
> 
> --
> Richard Jones, Virtualization Group, Red Hat
> http://people.redhat.com/~rjones
> virt-df lists disk usage of guests without needing to install any
> software inside the virtual machine.  Supports Linux and Windows.
> http://et.redhat.com/~rjones/virt-df/
>
Avi Kivity - Sept. 27, 2012, 9:03 a.m.
On 09/24/2012 01:11 PM, Paolo Bonzini wrote:
> 
> A better plan would be to incorporate this code into glib, completing
> the extremely sparse URI support that is already there.  However, we
> would not be able to use it anyway, because we support compiling on old
> glib versions.

If the same (or very similar) API is retained, we could fall back on
libxml2 when glib uri parsing is unavailable.  Eventually we bump our
minimum version requirement and drop the libxml2 dependency (or find out
that xml has invaded our code base and we can't get rid of it).
Paolo Bonzini - Sept. 27, 2012, 9:07 a.m.
Il 27/09/2012 11:03, Avi Kivity ha scritto:
> On 09/24/2012 01:11 PM, Paolo Bonzini wrote:
> > A better plan would be to incorporate this code into glib, completing
> > the extremely sparse URI support that is already there.  However, we
> > would not be able to use it anyway, because we support compiling on old
> > glib versions.
>
> If the same (or very similar) API is retained,

Yes, there is exactly one change in the API (modulo renaming) so we
could just use some #defines or wrappers.

> we could fall back on
> libxml2 when glib uri parsing is unavailable.

That's an interesting idea.  The assumption that glib wants URI parsing
is not proved, but it may work out.

Paolo

> Eventually we bump our
> minimum version requirement and drop the libxml2 dependency (or find out
> that xml has invaded our code base and we can't get rid of it).
Daniel Veillard - Oct. 2, 2012, 4:59 a.m.
On Thu, Sep 27, 2012 at 11:07:49AM +0200, Paolo Bonzini wrote:
> Il 27/09/2012 11:03, Avi Kivity ha scritto:
> > On 09/24/2012 01:11 PM, Paolo Bonzini wrote:
> > > A better plan would be to incorporate this code into glib, completing
> > > the extremely sparse URI support that is already there.  However, we
> > > would not be able to use it anyway, because we support compiling on old
> > > glib versions.
> >
> > If the same (or very similar) API is retained,
> 
> Yes, there is exactly one change in the API (modulo renaming) so we
> could just use some #defines or wrappers.

  BTW I'm fine by this assuming:
   - someone keeps an eye on libxml2 upstream in case some security
     problem shows up in that part of the code
   - the code used is the 2.9.0 one where I added quite a bit of
     cleanup on memory handling.

> > we could fall back on
> > libxml2 when glib uri parsing is unavailable.
> 
> That's an interesting idea.  The assumption that glib wants URI parsing
> is not proved, but it may work out.

  Well glib coding style and libxml2 one are fairly different, assuming
you get the change into glib, that will be a relatively different code
base (my recollection is that glib exits on allocation error which tend
to impact API design so this may be more complex than just different
naming for the functions).

Daniel

Patch

diff --git a/Makefile.objs b/Makefile.objs
index 4412757..7c1c682 100644
--- a/Makefile.objs
+++ b/Makefile.objs
@@ -42,7 +42,7 @@  coroutine-obj-$(CONFIG_WIN32) += coroutine-win32.o
 # block-obj-y is code used by both qemu system emulation and qemu-img
 
 block-obj-y = cutils.o iov.o cache-utils.o qemu-option.o module.o async.o
-block-obj-y += nbd.o block.o aio.o aes.o qemu-config.o qemu-progress.o qemu-sockets.o
+block-obj-y += nbd.o block.o aio.o aes.o qemu-config.o qemu-progress.o qemu-sockets.o uri.o
 block-obj-y += $(coroutine-obj-y) $(qobject-obj-y) $(version-obj-y)
 block-obj-$(CONFIG_POSIX) += posix-aio-compat.o
 block-obj-$(CONFIG_LINUX_AIO) += linux-aio.o
diff --git a/uri.c b/uri.c
new file mode 100644
index 0000000..dd922de
--- /dev/null
+++ b/uri.c
@@ -0,0 +1,2249 @@ 
+/**
+ * uri.c: set of generic URI related routines
+ *
+ * Reference: RFCs 3986, 2732 and 2373
+ *
+ * Copyright (C) 1998-2003 Daniel Veillard.  All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE
+ * DANIEL VEILLARD BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+ * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * Except as contained in this notice, the name of Daniel Veillard shall not
+ * be used in advertising or otherwise to promote the sale, use or other
+ * dealings in this Software without prior written authorization from him.
+ *
+ * daniel@veillard.com
+ *
+ **
+ *
+ * Copyright (C) 2007, 2009-2010 Red Hat, Inc.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307  USA
+ *
+ * Authors:
+ *    Richard W.M. Jones <rjones@redhat.com>
+ *
+ */
+
+#include <glib.h>
+#include <string.h>
+#include <stdio.h>
+
+#include "uri.h"
+
+static void uri_clean(URI *uri);
+
+/*
+ * Old rule from 2396 used in legacy handling code
+ * alpha    = lowalpha | upalpha
+ */
+#define IS_ALPHA(x) (IS_LOWALPHA(x) || IS_UPALPHA(x))
+
+
+/*
+ * lowalpha = "a" | "b" | "c" | "d" | "e" | "f" | "g" | "h" | "i" | "j" |
+ *            "k" | "l" | "m" | "n" | "o" | "p" | "q" | "r" | "s" | "t" |
+ *            "u" | "v" | "w" | "x" | "y" | "z"
+ */
+
+#define IS_LOWALPHA(x) (((x) >= 'a') && ((x) <= 'z'))
+
+/*
+ * upalpha = "A" | "B" | "C" | "D" | "E" | "F" | "G" | "H" | "I" | "J" |
+ *           "K" | "L" | "M" | "N" | "O" | "P" | "Q" | "R" | "S" | "T" |
+ *           "U" | "V" | "W" | "X" | "Y" | "Z"
+ */
+#define IS_UPALPHA(x) (((x) >= 'A') && ((x) <= 'Z'))
+
+#ifdef IS_DIGIT
+#undef IS_DIGIT
+#endif
+/*
+ * digit = "0" | "1" | "2" | "3" | "4" | "5" | "6" | "7" | "8" | "9"
+ */
+#define IS_DIGIT(x) (((x) >= '0') && ((x) <= '9'))
+
+/*
+ * alphanum = alpha | digit
+ */
+
+#define IS_ALPHANUM(x) (IS_ALPHA(x) || IS_DIGIT(x))
+
+/*
+ * mark = "-" | "_" | "." | "!" | "~" | "*" | "'" | "(" | ")"
+ */
+
+#define IS_MARK(x) (((x) == '-') || ((x) == '_') || ((x) == '.') ||     \
+    ((x) == '!') || ((x) == '~') || ((x) == '*') || ((x) == '\'') ||    \
+    ((x) == '(') || ((x) == ')'))
+
+/*
+ * unwise = "{" | "}" | "|" | "\" | "^" | "`"
+ */
+
+#define IS_UNWISE(p)                                                    \
+      (((*(p) == '{')) || ((*(p) == '}')) || ((*(p) == '|')) ||         \
+       ((*(p) == '\\')) || ((*(p) == '^')) || ((*(p) == '[')) ||        \
+       ((*(p) == ']')) || ((*(p) == '`')))
+/*
+ * reserved = ";" | "/" | "?" | ":" | "@" | "&" | "=" | "+" | "$" | "," |
+ *            "[" | "]"
+ */
+
+#define IS_RESERVED(x) (((x) == ';') || ((x) == '/') || ((x) == '?') || \
+        ((x) == ':') || ((x) == '@') || ((x) == '&') || ((x) == '=') || \
+        ((x) == '+') || ((x) == '$') || ((x) == ',') || ((x) == '[') || \
+        ((x) == ']'))
+
+/*
+ * unreserved = alphanum | mark
+ */
+
+#define IS_UNRESERVED(x) (IS_ALPHANUM(x) || IS_MARK(x))
+
+/*
+ * Skip to next pointer char, handle escaped sequences
+ */
+
+#define NEXT(p) ((*p == '%')? p += 3 : p++)
+
+/*
+ * Productions from the spec.
+ *
+ *    authority     = server | reg_name
+ *    reg_name      = 1*( unreserved | escaped | "$" | "," |
+ *                        ";" | ":" | "@" | "&" | "=" | "+" )
+ *
+ * path          = [ abs_path | opaque_part ]
+ */
+
+
+/************************************************************************
+ *									*
+ *                         RFC 3986 parser				*
+ *									*
+ ************************************************************************/
+
+#define ISA_DIGIT(p) ((*(p) >= '0') && (*(p) <= '9'))
+#define ISA_ALPHA(p) (((*(p) >= 'a') && (*(p) <= 'z')) ||		\
+                      ((*(p) >= 'A') && (*(p) <= 'Z')))
+#define ISA_HEXDIG(p)							\
+       (ISA_DIGIT(p) || ((*(p) >= 'a') && (*(p) <= 'f')) ||		\
+        ((*(p) >= 'A') && (*(p) <= 'F')))
+
+/*
+ *    sub-delims    = "!" / "$" / "&" / "'" / "(" / ")"
+ *                     / "*" / "+" / "," / ";" / "="
+ */
+#define ISA_SUB_DELIM(p)						\
+      (((*(p) == '!')) || ((*(p) == '$')) || ((*(p) == '&')) ||		\
+       ((*(p) == '(')) || ((*(p) == ')')) || ((*(p) == '*')) ||		\
+       ((*(p) == '+')) || ((*(p) == ',')) || ((*(p) == ';')) ||		\
+       ((*(p) == '=')) || ((*(p) == '\'')))
+
+/*
+ *    gen-delims    = ":" / "/" / "?" / "#" / "[" / "]" / "@"
+ */
+#define ISA_GEN_DELIM(p)						\
+      (((*(p) == ':')) || ((*(p) == '/')) || ((*(p) == '?')) ||         \
+       ((*(p) == '#')) || ((*(p) == '[')) || ((*(p) == ']')) ||         \
+       ((*(p) == '@')))
+
+/*
+ *    reserved      = gen-delims / sub-delims
+ */
+#define ISA_RESERVED(p) (ISA_GEN_DELIM(p) || (ISA_SUB_DELIM(p)))
+
+/*
+ *    unreserved    = ALPHA / DIGIT / "-" / "." / "_" / "~"
+ */
+#define ISA_UNRESERVED(p)						\
+      ((ISA_ALPHA(p)) || (ISA_DIGIT(p)) || ((*(p) == '-')) ||		\
+       ((*(p) == '.')) || ((*(p) == '_')) || ((*(p) == '~')))
+
+/*
+ *    pct-encoded   = "%" HEXDIG HEXDIG
+ */
+#define ISA_PCT_ENCODED(p)						\
+     ((*(p) == '%') && (ISA_HEXDIG(p + 1)) && (ISA_HEXDIG(p + 2)))
+
+/*
+ *    pchar         = unreserved / pct-encoded / sub-delims / ":" / "@"
+ */
+#define ISA_PCHAR(p)							\
+     (ISA_UNRESERVED(p) || ISA_PCT_ENCODED(p) || ISA_SUB_DELIM(p) ||	\
+      ((*(p) == ':')) || ((*(p) == '@')))
+
+/**
+ * rfc3986_parse_scheme:
+ * @uri:  pointer to an URI structure
+ * @str:  pointer to the string to analyze
+ *
+ * Parse an URI scheme
+ *
+ * ALPHA *( ALPHA / DIGIT / "+" / "-" / "." )
+ *
+ * Returns 0 or the error code
+ */
+static int
+rfc3986_parse_scheme(URI *uri, const char **str) {
+    const char *cur;
+
+    if (str == NULL)
+	return(-1);
+
+    cur = *str;
+    if (!ISA_ALPHA(cur))
+	return(2);
+    cur++;
+    while (ISA_ALPHA(cur) || ISA_DIGIT(cur) ||
+           (*cur == '+') || (*cur == '-') || (*cur == '.')) cur++;
+    if (uri != NULL) {
+	if (uri->scheme != NULL) g_free(uri->scheme);
+	uri->scheme = g_strndup(*str, cur - *str);
+    }
+    *str = cur;
+    return(0);
+}
+
+/**
+ * rfc3986_parse_fragment:
+ * @uri:  pointer to an URI structure
+ * @str:  pointer to the string to analyze
+ *
+ * Parse the query part of an URI
+ *
+ * fragment      = *( pchar / "/" / "?" )
+ * NOTE: the strict syntax as defined by 3986 does not allow '[' and ']'
+ *       in the fragment identifier but this is used very broadly for
+ *       xpointer scheme selection, so we are allowing it here to not break
+ *       for example all the DocBook processing chains.
+ *
+ * Returns 0 or the error code
+ */
+static int
+rfc3986_parse_fragment(URI *uri, const char **str)
+{
+    const char *cur;
+
+    if (str == NULL)
+        return (-1);
+
+    cur = *str;
+
+    while ((ISA_PCHAR(cur)) || (*cur == '/') || (*cur == '?') ||
+           (*cur == '[') || (*cur == ']') ||
+           ((uri != NULL) && (uri->cleanup & 1) && (IS_UNWISE(cur))))
+        NEXT(cur);
+    if (uri != NULL) {
+        if (uri->fragment != NULL)
+            g_free(uri->fragment);
+	if (uri->cleanup & 2)
+	    uri->fragment = g_strndup(*str, cur - *str);
+	else
+	    uri->fragment = uri_string_unescape(*str, cur - *str, NULL);
+    }
+    *str = cur;
+    return (0);
+}
+
+/**
+ * rfc3986_parse_query:
+ * @uri:  pointer to an URI structure
+ * @str:  pointer to the string to analyze
+ *
+ * Parse the query part of an URI
+ *
+ * query = *uric
+ *
+ * Returns 0 or the error code
+ */
+static int
+rfc3986_parse_query(URI *uri, const char **str)
+{
+    const char *cur;
+
+    if (str == NULL)
+        return (-1);
+
+    cur = *str;
+
+    while ((ISA_PCHAR(cur)) || (*cur == '/') || (*cur == '?') ||
+           ((uri != NULL) && (uri->cleanup & 1) && (IS_UNWISE(cur))))
+        NEXT(cur);
+    if (uri != NULL) {
+	if (uri->query != NULL)
+	    g_free (uri->query);
+	uri->query = g_strndup (*str, cur - *str);
+    }
+    *str = cur;
+    return (0);
+}
+
+/**
+ * rfc3986_parse_port:
+ * @uri:  pointer to an URI structure
+ * @str:  the string to analyze
+ *
+ * Parse a port  part and fills in the appropriate fields
+ * of the @uri structure
+ *
+ * port          = *DIGIT
+ *
+ * Returns 0 or the error code
+ */
+static int
+rfc3986_parse_port(URI *uri, const char **str)
+{
+    const char *cur = *str;
+
+    if (ISA_DIGIT(cur)) {
+	if (uri != NULL)
+	    uri->port = 0;
+	while (ISA_DIGIT(cur)) {
+	    if (uri != NULL)
+		uri->port = uri->port * 10 + (*cur - '0');
+	    cur++;
+	}
+	*str = cur;
+	return(0);
+    }
+    return(1);
+}
+
+/**
+ * rfc3986_parse_user_info:
+ * @uri:  pointer to an URI structure
+ * @str:  the string to analyze
+ *
+ * Parse an user informations part and fills in the appropriate fields
+ * of the @uri structure
+ *
+ * userinfo      = *( unreserved / pct-encoded / sub-delims / ":" )
+ *
+ * Returns 0 or the error code
+ */
+static int
+rfc3986_parse_user_info(URI *uri, const char **str)
+{
+    const char *cur;
+
+    cur = *str;
+    while (ISA_UNRESERVED(cur) || ISA_PCT_ENCODED(cur) ||
+           ISA_SUB_DELIM(cur) || (*cur == ':'))
+	NEXT(cur);
+    if (*cur == '@') {
+	if (uri != NULL) {
+	    if (uri->user != NULL) g_free(uri->user);
+	    if (uri->cleanup & 2)
+		uri->user = g_strndup(*str, cur - *str);
+	    else
+		uri->user = uri_string_unescape(*str, cur - *str, NULL);
+	}
+	*str = cur;
+	return(0);
+    }
+    return(1);
+}
+
+/**
+ * rfc3986_parse_dec_octet:
+ * @str:  the string to analyze
+ *
+ *    dec-octet     = DIGIT                 ; 0-9
+ *                  / %x31-39 DIGIT         ; 10-99
+ *                  / "1" 2DIGIT            ; 100-199
+ *                  / "2" %x30-34 DIGIT     ; 200-249
+ *                  / "25" %x30-35          ; 250-255
+ *
+ * Skip a dec-octet.
+ *
+ * Returns 0 if found and skipped, 1 otherwise
+ */
+static int
+rfc3986_parse_dec_octet(const char **str) {
+    const char *cur = *str;
+
+    if (!(ISA_DIGIT(cur)))
+        return(1);
+    if (!ISA_DIGIT(cur+1))
+	cur++;
+    else if ((*cur != '0') && (ISA_DIGIT(cur + 1)) && (!ISA_DIGIT(cur+2)))
+	cur += 2;
+    else if ((*cur == '1') && (ISA_DIGIT(cur + 1)) && (ISA_DIGIT(cur + 2)))
+	cur += 3;
+    else if ((*cur == '2') && (*(cur + 1) >= '0') &&
+	     (*(cur + 1) <= '4') && (ISA_DIGIT(cur + 2)))
+	cur += 3;
+    else if ((*cur == '2') && (*(cur + 1) == '5') &&
+	     (*(cur + 2) >= '0') && (*(cur + 1) <= '5'))
+	cur += 3;
+    else
+        return(1);
+    *str = cur;
+    return(0);
+}
+/**
+ * rfc3986_parse_host:
+ * @uri:  pointer to an URI structure
+ * @str:  the string to analyze
+ *
+ * Parse an host part and fills in the appropriate fields
+ * of the @uri structure
+ *
+ * host          = IP-literal / IPv4address / reg-name
+ * IP-literal    = "[" ( IPv6address / IPvFuture  ) "]"
+ * IPv4address   = dec-octet "." dec-octet "." dec-octet "." dec-octet
+ * reg-name      = *( unreserved / pct-encoded / sub-delims )
+ *
+ * Returns 0 or the error code
+ */
+static int
+rfc3986_parse_host(URI *uri, const char **str)
+{
+    const char *cur = *str;
+    const char *host;
+
+    host = cur;
+    /*
+     * IPv6 and future adressing scheme are enclosed between brackets
+     */
+    if (*cur == '[') {
+        cur++;
+	while ((*cur != ']') && (*cur != 0))
+	    cur++;
+	if (*cur != ']')
+	    return(1);
+	cur++;
+	goto found;
+    }
+    /*
+     * try to parse an IPv4
+     */
+    if (ISA_DIGIT(cur)) {
+        if (rfc3986_parse_dec_octet(&cur) != 0)
+	    goto not_ipv4;
+	if (*cur != '.')
+	    goto not_ipv4;
+	cur++;
+        if (rfc3986_parse_dec_octet(&cur) != 0)
+	    goto not_ipv4;
+	if (*cur != '.')
+	    goto not_ipv4;
+        if (rfc3986_parse_dec_octet(&cur) != 0)
+	    goto not_ipv4;
+	if (*cur != '.')
+	    goto not_ipv4;
+        if (rfc3986_parse_dec_octet(&cur) != 0)
+	    goto not_ipv4;
+	goto found;
+not_ipv4:
+        cur = *str;
+    }
+    /*
+     * then this should be a hostname which can be empty
+     */
+    while (ISA_UNRESERVED(cur) || ISA_PCT_ENCODED(cur) || ISA_SUB_DELIM(cur))
+        NEXT(cur);
+found:
+    if (uri != NULL) {
+	if (uri->authority != NULL) g_free(uri->authority);
+	uri->authority = NULL;
+	if (uri->server != NULL) g_free(uri->server);
+	if (cur != host) {
+	    if (uri->cleanup & 2)
+		uri->server = g_strndup(host, cur - host);
+	    else
+		uri->server = uri_string_unescape(host, cur - host, NULL);
+	} else
+	    uri->server = NULL;
+    }
+    *str = cur;
+    return(0);
+}
+
+/**
+ * rfc3986_parse_authority:
+ * @uri:  pointer to an URI structure
+ * @str:  the string to analyze
+ *
+ * Parse an authority part and fills in the appropriate fields
+ * of the @uri structure
+ *
+ * authority     = [ userinfo "@" ] host [ ":" port ]
+ *
+ * Returns 0 or the error code
+ */
+static int
+rfc3986_parse_authority(URI *uri, const char **str)
+{
+    const char *cur;
+    int ret;
+
+    cur = *str;
+    /*
+     * try to parse an userinfo and check for the trailing @
+     */
+    ret = rfc3986_parse_user_info(uri, &cur);
+    if ((ret != 0) || (*cur != '@'))
+        cur = *str;
+    else
+        cur++;
+    ret = rfc3986_parse_host(uri, &cur);
+    if (ret != 0) return(ret);
+    if (*cur == ':') {
+        cur++;
+        ret = rfc3986_parse_port(uri, &cur);
+	if (ret != 0) return(ret);
+    }
+    *str = cur;
+    return(0);
+}
+
+/**
+ * rfc3986_parse_segment:
+ * @str:  the string to analyze
+ * @forbid: an optional forbidden character
+ * @empty: allow an empty segment
+ *
+ * Parse a segment and fills in the appropriate fields
+ * of the @uri structure
+ *
+ * segment       = *pchar
+ * segment-nz    = 1*pchar
+ * segment-nz-nc = 1*( unreserved / pct-encoded / sub-delims / "@" )
+ *               ; non-zero-length segment without any colon ":"
+ *
+ * Returns 0 or the error code
+ */
+static int
+rfc3986_parse_segment(const char **str, char forbid, int empty)
+{
+    const char *cur;
+
+    cur = *str;
+    if (!ISA_PCHAR(cur)) {
+        if (empty)
+	    return(0);
+	return(1);
+    }
+    while (ISA_PCHAR(cur) && (*cur != forbid))
+        NEXT(cur);
+    *str = cur;
+    return (0);
+}
+
+/**
+ * rfc3986_parse_path_ab_empty:
+ * @uri:  pointer to an URI structure
+ * @str:  the string to analyze
+ *
+ * Parse an path absolute or empty and fills in the appropriate fields
+ * of the @uri structure
+ *
+ * path-abempty  = *( "/" segment )
+ *
+ * Returns 0 or the error code
+ */
+static int
+rfc3986_parse_path_ab_empty(URI *uri, const char **str)
+{
+    const char *cur;
+    int ret;
+
+    cur = *str;
+
+    while (*cur == '/') {
+        cur++;
+	ret = rfc3986_parse_segment(&cur, 0, 1);
+	if (ret != 0) return(ret);
+    }
+    if (uri != NULL) {
+	if (uri->path != NULL) g_free(uri->path);
+        if (*str != cur) {
+            if (uri->cleanup & 2)
+                uri->path = g_strndup(*str, cur - *str);
+            else
+                uri->path = uri_string_unescape(*str, cur - *str, NULL);
+        } else {
+            uri->path = NULL;
+        }
+    }
+    *str = cur;
+    return (0);
+}
+
+/**
+ * rfc3986_parse_path_absolute:
+ * @uri:  pointer to an URI structure
+ * @str:  the string to analyze
+ *
+ * Parse an path absolute and fills in the appropriate fields
+ * of the @uri structure
+ *
+ * path-absolute = "/" [ segment-nz *( "/" segment ) ]
+ *
+ * Returns 0 or the error code
+ */
+static int
+rfc3986_parse_path_absolute(URI *uri, const char **str)
+{
+    const char *cur;
+    int ret;
+
+    cur = *str;
+
+    if (*cur != '/')
+        return(1);
+    cur++;
+    ret = rfc3986_parse_segment(&cur, 0, 0);
+    if (ret == 0) {
+	while (*cur == '/') {
+	    cur++;
+	    ret = rfc3986_parse_segment(&cur, 0, 1);
+	    if (ret != 0) return(ret);
+	}
+    }
+    if (uri != NULL) {
+	if (uri->path != NULL) g_free(uri->path);
+        if (cur != *str) {
+            if (uri->cleanup & 2)
+                uri->path = g_strndup(*str, cur - *str);
+            else
+                uri->path = uri_string_unescape(*str, cur - *str, NULL);
+        } else {
+            uri->path = NULL;
+        }
+    }
+    *str = cur;
+    return (0);
+}
+
+/**
+ * rfc3986_parse_path_rootless:
+ * @uri:  pointer to an URI structure
+ * @str:  the string to analyze
+ *
+ * Parse an path without root and fills in the appropriate fields
+ * of the @uri structure
+ *
+ * path-rootless = segment-nz *( "/" segment )
+ *
+ * Returns 0 or the error code
+ */
+static int
+rfc3986_parse_path_rootless(URI *uri, const char **str)
+{
+    const char *cur;
+    int ret;
+
+    cur = *str;
+
+    ret = rfc3986_parse_segment(&cur, 0, 0);
+    if (ret != 0) return(ret);
+    while (*cur == '/') {
+        cur++;
+	ret = rfc3986_parse_segment(&cur, 0, 1);
+	if (ret != 0) return(ret);
+    }
+    if (uri != NULL) {
+	if (uri->path != NULL) g_free(uri->path);
+        if (cur != *str) {
+            if (uri->cleanup & 2)
+                uri->path = g_strndup(*str, cur - *str);
+            else
+                uri->path = uri_string_unescape(*str, cur - *str, NULL);
+        } else {
+            uri->path = NULL;
+        }
+    }
+    *str = cur;
+    return (0);
+}
+
+/**
+ * rfc3986_parse_path_no_scheme:
+ * @uri:  pointer to an URI structure
+ * @str:  the string to analyze
+ *
+ * Parse an path which is not a scheme and fills in the appropriate fields
+ * of the @uri structure
+ *
+ * path-noscheme = segment-nz-nc *( "/" segment )
+ *
+ * Returns 0 or the error code
+ */
+static int
+rfc3986_parse_path_no_scheme(URI *uri, const char **str)
+{
+    const char *cur;
+    int ret;
+
+    cur = *str;
+
+    ret = rfc3986_parse_segment(&cur, ':', 0);
+    if (ret != 0) return(ret);
+    while (*cur == '/') {
+        cur++;
+	ret = rfc3986_parse_segment(&cur, 0, 1);
+	if (ret != 0) return(ret);
+    }
+    if (uri != NULL) {
+	if (uri->path != NULL) g_free(uri->path);
+        if (cur != *str) {
+            if (uri->cleanup & 2)
+                uri->path = g_strndup(*str, cur - *str);
+            else
+                uri->path = uri_string_unescape(*str, cur - *str, NULL);
+        } else {
+            uri->path = NULL;
+        }
+    }
+    *str = cur;
+    return (0);
+}
+
+/**
+ * rfc3986_parse_hier_part:
+ * @uri:  pointer to an URI structure
+ * @str:  the string to analyze
+ *
+ * Parse an hierarchical part and fills in the appropriate fields
+ * of the @uri structure
+ *
+ * hier-part     = "//" authority path-abempty
+ *                / path-absolute
+ *                / path-rootless
+ *                / path-empty
+ *
+ * Returns 0 or the error code
+ */
+static int
+rfc3986_parse_hier_part(URI *uri, const char **str)
+{
+    const char *cur;
+    int ret;
+
+    cur = *str;
+
+    if ((*cur == '/') && (*(cur + 1) == '/')) {
+        cur += 2;
+	ret = rfc3986_parse_authority(uri, &cur);
+	if (ret != 0) return(ret);
+	ret = rfc3986_parse_path_ab_empty(uri, &cur);
+	if (ret != 0) return(ret);
+	*str = cur;
+	return(0);
+    } else if (*cur == '/') {
+        ret = rfc3986_parse_path_absolute(uri, &cur);
+	if (ret != 0) return(ret);
+    } else if (ISA_PCHAR(cur)) {
+        ret = rfc3986_parse_path_rootless(uri, &cur);
+	if (ret != 0) return(ret);
+    } else {
+	/* path-empty is effectively empty */
+	if (uri != NULL) {
+	    if (uri->path != NULL) g_free(uri->path);
+	    uri->path = NULL;
+	}
+    }
+    *str = cur;
+    return (0);
+}
+
+/**
+ * rfc3986_parse_relative_ref:
+ * @uri:  pointer to an URI structure
+ * @str:  the string to analyze
+ *
+ * Parse an URI string and fills in the appropriate fields
+ * of the @uri structure
+ *
+ * relative-ref  = relative-part [ "?" query ] [ "#" fragment ]
+ * relative-part = "//" authority path-abempty
+ *               / path-absolute
+ *               / path-noscheme
+ *               / path-empty
+ *
+ * Returns 0 or the error code
+ */
+static int
+rfc3986_parse_relative_ref(URI *uri, const char *str) {
+    int ret;
+
+    if ((*str == '/') && (*(str + 1) == '/')) {
+        str += 2;
+	ret = rfc3986_parse_authority(uri, &str);
+	if (ret != 0) return(ret);
+	ret = rfc3986_parse_path_ab_empty(uri, &str);
+	if (ret != 0) return(ret);
+    } else if (*str == '/') {
+	ret = rfc3986_parse_path_absolute(uri, &str);
+	if (ret != 0) return(ret);
+    } else if (ISA_PCHAR(str)) {
+        ret = rfc3986_parse_path_no_scheme(uri, &str);
+	if (ret != 0) return(ret);
+    } else {
+	/* path-empty is effectively empty */
+	if (uri != NULL) {
+	    if (uri->path != NULL) g_free(uri->path);
+	    uri->path = NULL;
+	}
+    }
+
+    if (*str == '?') {
+	str++;
+	ret = rfc3986_parse_query(uri, &str);
+	if (ret != 0) return(ret);
+    }
+    if (*str == '#') {
+	str++;
+	ret = rfc3986_parse_fragment(uri, &str);
+	if (ret != 0) return(ret);
+    }
+    if (*str != 0) {
+	uri_clean(uri);
+	return(1);
+    }
+    return(0);
+}
+
+
+/**
+ * rfc3986_parse:
+ * @uri:  pointer to an URI structure
+ * @str:  the string to analyze
+ *
+ * Parse an URI string and fills in the appropriate fields
+ * of the @uri structure
+ *
+ * scheme ":" hier-part [ "?" query ] [ "#" fragment ]
+ *
+ * Returns 0 or the error code
+ */
+static int
+rfc3986_parse(URI *uri, const char *str) {
+    int ret;
+
+    ret = rfc3986_parse_scheme(uri, &str);
+    if (ret != 0) return(ret);
+    if (*str != ':') {
+	return(1);
+    }
+    str++;
+    ret = rfc3986_parse_hier_part(uri, &str);
+    if (ret != 0) return(ret);
+    if (*str == '?') {
+	str++;
+	ret = rfc3986_parse_query(uri, &str);
+	if (ret != 0) return(ret);
+    }
+    if (*str == '#') {
+	str++;
+	ret = rfc3986_parse_fragment(uri, &str);
+	if (ret != 0) return(ret);
+    }
+    if (*str != 0) {
+	uri_clean(uri);
+	return(1);
+    }
+    return(0);
+}
+
+/**
+ * rfc3986_parse_uri_reference:
+ * @uri:  pointer to an URI structure
+ * @str:  the string to analyze
+ *
+ * Parse an URI reference string and fills in the appropriate fields
+ * of the @uri structure
+ *
+ * URI-reference = URI / relative-ref
+ *
+ * Returns 0 or the error code
+ */
+static int
+rfc3986_parse_uri_reference(URI *uri, const char *str) {
+    int ret;
+
+    if (str == NULL)
+	return(-1);
+    uri_clean(uri);
+
+    /*
+     * Try first to parse absolute refs, then fallback to relative if
+     * it fails.
+     */
+    ret = rfc3986_parse(uri, str);
+    if (ret != 0) {
+	uri_clean(uri);
+        ret = rfc3986_parse_relative_ref(uri, str);
+	if (ret != 0) {
+	    uri_clean(uri);
+	    return(ret);
+	}
+    }
+    return(0);
+}
+
+/**
+ * uri_parse:
+ * @str:  the URI string to analyze
+ *
+ * Parse an URI based on RFC 3986
+ *
+ * URI-reference = [ absoluteURI | relativeURI ] [ "#" fragment ]
+ *
+ * Returns a newly built URI or NULL in case of error
+ */
+URI *
+uri_parse(const char *str) {
+    URI *uri;
+    int ret;
+
+    if (str == NULL)
+	return(NULL);
+    uri = uri_new();
+    if (uri != NULL) {
+	ret = rfc3986_parse_uri_reference(uri, str);
+        if (ret) {
+	    uri_free(uri);
+	    return(NULL);
+	}
+    }
+    return(uri);
+}
+
+/**
+ * uri_parse_into:
+ * @uri:  pointer to an URI structure
+ * @str:  the string to analyze
+ *
+ * Parse an URI reference string based on RFC 3986 and fills in the
+ * appropriate fields of the @uri structure
+ *
+ * URI-reference = URI / relative-ref
+ *
+ * Returns 0 or the error code
+ */
+int
+uri_parse_into(URI *uri, const char *str) {
+    return(rfc3986_parse_uri_reference(uri, str));
+}
+
+/**
+ * uri_parse_raw:
+ * @str:  the URI string to analyze
+ * @raw:  if 1 unescaping of URI pieces are disabled
+ *
+ * Parse an URI but allows to keep intact the original fragments.
+ *
+ * URI-reference = URI / relative-ref
+ *
+ * Returns a newly built URI or NULL in case of error
+ */
+URI *
+uri_parse_raw(const char *str, int raw) {
+    URI *uri;
+    int ret;
+
+    if (str == NULL)
+	return(NULL);
+    uri = uri_new();
+    if (uri != NULL) {
+        if (raw) {
+	    uri->cleanup |= 2;
+	}
+	ret = uri_parse_into(uri, str);
+        if (ret) {
+	    uri_free(uri);
+	    return(NULL);
+	}
+    }
+    return(uri);
+}
+
+/************************************************************************
+ *									*
+ *			Generic URI structure functions			*
+ *									*
+ ************************************************************************/
+
+/**
+ * uri_new:
+ *
+ * Simply creates an empty URI
+ *
+ * Returns the new structure or NULL in case of error
+ */
+URI *
+uri_new(void) {
+    URI *ret;
+
+    ret = (URI *) g_malloc(sizeof(URI));
+    memset(ret, 0, sizeof(URI));
+    return(ret);
+}
+
+/**
+ * realloc2n:
+ *
+ * Function to handle properly a reallocation when saving an URI
+ * Also imposes some limit on the length of an URI string output
+ */
+static char *
+realloc2n(char *ret, int *max) {
+    char *temp;
+    int tmp;
+
+    tmp = *max * 2;
+    temp = g_realloc(ret, (tmp + 1));
+    *max = tmp;
+    return(temp);
+}
+
+/**
+ * uri_to_string:
+ * @uri:  pointer to an URI
+ *
+ * Save the URI as an escaped string
+ *
+ * Returns a new string (to be deallocated by caller)
+ */
+char *
+uri_to_string(URI *uri) {
+    char *ret = NULL;
+    char *temp;
+    const char *p;
+    int len;
+    int max;
+
+    if (uri == NULL) return(NULL);
+
+
+    max = 80;
+    ret = g_malloc(max + 1);
+    len = 0;
+
+    if (uri->scheme != NULL) {
+	p = uri->scheme;
+	while (*p != 0) {
+	    if (len >= max) {
+                temp = realloc2n(ret, &max);
+                if (temp == NULL) goto mem_error;
+		ret = temp;
+	    }
+	    ret[len++] = *p++;
+	}
+	if (len >= max) {
+            temp = realloc2n(ret, &max);
+            if (temp == NULL) goto mem_error;
+            ret = temp;
+	}
+	ret[len++] = ':';
+    }
+    if (uri->opaque != NULL) {
+	p = uri->opaque;
+	while (*p != 0) {
+	    if (len + 3 >= max) {
+                temp = realloc2n(ret, &max);
+                if (temp == NULL) goto mem_error;
+                ret = temp;
+	    }
+	    if (IS_RESERVED(*(p)) || IS_UNRESERVED(*(p)))
+		ret[len++] = *p++;
+	    else {
+		int val = *(unsigned char *)p++;
+		int hi = val / 0x10, lo = val % 0x10;
+		ret[len++] = '%';
+		ret[len++] = hi + (hi > 9? 'A'-10 : '0');
+		ret[len++] = lo + (lo > 9? 'A'-10 : '0');
+	    }
+	}
+    } else {
+	if (uri->server != NULL) {
+	    if (len + 3 >= max) {
+                temp = realloc2n(ret, &max);
+                if (temp == NULL) goto mem_error;
+                ret = temp;
+	    }
+	    ret[len++] = '/';
+	    ret[len++] = '/';
+	    if (uri->user != NULL) {
+		p = uri->user;
+		while (*p != 0) {
+		    if (len + 3 >= max) {
+                        temp = realloc2n(ret, &max);
+                        if (temp == NULL) goto mem_error;
+                        ret = temp;
+		    }
+		    if ((IS_UNRESERVED(*(p))) ||
+			((*(p) == ';')) || ((*(p) == ':')) ||
+			((*(p) == '&')) || ((*(p) == '=')) ||
+			((*(p) == '+')) || ((*(p) == '$')) ||
+			((*(p) == ',')))
+			ret[len++] = *p++;
+		    else {
+			int val = *(unsigned char *)p++;
+			int hi = val / 0x10, lo = val % 0x10;
+			ret[len++] = '%';
+			ret[len++] = hi + (hi > 9? 'A'-10 : '0');
+			ret[len++] = lo + (lo > 9? 'A'-10 : '0');
+		    }
+		}
+		if (len + 3 >= max) {
+                    temp = realloc2n(ret, &max);
+                    if (temp == NULL) goto mem_error;
+                    ret = temp;
+		}
+		ret[len++] = '@';
+	    }
+	    p = uri->server;
+	    while (*p != 0) {
+		if (len >= max) {
+                    temp = realloc2n(ret, &max);
+                    if (temp == NULL) goto mem_error;
+                    ret = temp;
+		}
+		ret[len++] = *p++;
+	    }
+	    if (uri->port > 0) {
+		if (len + 10 >= max) {
+                    temp = realloc2n(ret, &max);
+                    if (temp == NULL) goto mem_error;
+                    ret = temp;
+		}
+		len += snprintf(&ret[len], max - len, ":%d", uri->port);
+	    }
+	} else if (uri->authority != NULL) {
+	    if (len + 3 >= max) {
+                temp = realloc2n(ret, &max);
+                if (temp == NULL) goto mem_error;
+                ret = temp;
+	    }
+	    ret[len++] = '/';
+	    ret[len++] = '/';
+	    p = uri->authority;
+	    while (*p != 0) {
+		if (len + 3 >= max) {
+                    temp = realloc2n(ret, &max);
+                    if (temp == NULL) goto mem_error;
+                    ret = temp;
+		}
+		if ((IS_UNRESERVED(*(p))) ||
+                    ((*(p) == '$')) || ((*(p) == ',')) || ((*(p) == ';')) ||
+                    ((*(p) == ':')) || ((*(p) == '@')) || ((*(p) == '&')) ||
+                    ((*(p) == '=')) || ((*(p) == '+')))
+		    ret[len++] = *p++;
+		else {
+		    int val = *(unsigned char *)p++;
+		    int hi = val / 0x10, lo = val % 0x10;
+		    ret[len++] = '%';
+		    ret[len++] = hi + (hi > 9? 'A'-10 : '0');
+		    ret[len++] = lo + (lo > 9? 'A'-10 : '0');
+		}
+	    }
+	} else if (uri->scheme != NULL) {
+	    if (len + 3 >= max) {
+                temp = realloc2n(ret, &max);
+                if (temp == NULL) goto mem_error;
+                ret = temp;
+	    }
+	    ret[len++] = '/';
+	    ret[len++] = '/';
+	}
+	if (uri->path != NULL) {
+	    p = uri->path;
+	    /*
+	     * the colon in file:///d: should not be escaped or
+	     * Windows accesses fail later.
+	     */
+	    if ((uri->scheme != NULL) &&
+		(p[0] == '/') &&
+		(((p[1] >= 'a') && (p[1] <= 'z')) ||
+		 ((p[1] >= 'A') && (p[1] <= 'Z'))) &&
+		(p[2] == ':') &&
+	        (!strcmp(uri->scheme, "file"))) {
+		if (len + 3 >= max) {
+                    temp = realloc2n(ret, &max);
+                    if (temp == NULL) goto mem_error;
+                    ret = temp;
+		}
+		ret[len++] = *p++;
+		ret[len++] = *p++;
+		ret[len++] = *p++;
+	    }
+	    while (*p != 0) {
+		if (len + 3 >= max) {
+                    temp = realloc2n(ret, &max);
+                    if (temp == NULL) goto mem_error;
+                    ret = temp;
+		}
+		if ((IS_UNRESERVED(*(p))) || ((*(p) == '/')) ||
+                    ((*(p) == ';')) || ((*(p) == '@')) || ((*(p) == '&')) ||
+	            ((*(p) == '=')) || ((*(p) == '+')) || ((*(p) == '$')) ||
+	            ((*(p) == ',')))
+		    ret[len++] = *p++;
+		else {
+		    int val = *(unsigned char *)p++;
+		    int hi = val / 0x10, lo = val % 0x10;
+		    ret[len++] = '%';
+		    ret[len++] = hi + (hi > 9? 'A'-10 : '0');
+		    ret[len++] = lo + (lo > 9? 'A'-10 : '0');
+		}
+	    }
+	}
+	if (uri->query != NULL) {
+	    if (len + 1 >= max) {
+                temp = realloc2n(ret, &max);
+                if (temp == NULL) goto mem_error;
+                ret = temp;
+	    }
+	    ret[len++] = '?';
+	    p = uri->query;
+	    while (*p != 0) {
+		if (len + 1 >= max) {
+                    temp = realloc2n(ret, &max);
+                    if (temp == NULL) goto mem_error;
+                    ret = temp;
+		}
+		ret[len++] = *p++;
+	    }
+	}
+    }
+    if (uri->fragment != NULL) {
+	if (len + 3 >= max) {
+            temp = realloc2n(ret, &max);
+            if (temp == NULL) goto mem_error;
+            ret = temp;
+	}
+	ret[len++] = '#';
+	p = uri->fragment;
+	while (*p != 0) {
+	    if (len + 3 >= max) {
+                temp = realloc2n(ret, &max);
+                if (temp == NULL) goto mem_error;
+                ret = temp;
+	    }
+	    if ((IS_UNRESERVED(*(p))) || (IS_RESERVED(*(p))))
+		ret[len++] = *p++;
+	    else {
+		int val = *(unsigned char *)p++;
+		int hi = val / 0x10, lo = val % 0x10;
+		ret[len++] = '%';
+		ret[len++] = hi + (hi > 9? 'A'-10 : '0');
+		ret[len++] = lo + (lo > 9? 'A'-10 : '0');
+	    }
+	}
+    }
+    if (len >= max) {
+        temp = realloc2n(ret, &max);
+        if (temp == NULL) goto mem_error;
+        ret = temp;
+    }
+    ret[len] = 0;
+    return(ret);
+
+mem_error:
+    g_free(ret);
+    return(NULL);
+}
+
+/**
+ * uri_clean:
+ * @uri:  pointer to an URI
+ *
+ * Make sure the URI struct is free of content
+ */
+static void
+uri_clean(URI *uri) {
+    if (uri == NULL) return;
+
+    if (uri->scheme != NULL) g_free(uri->scheme);
+    uri->scheme = NULL;
+    if (uri->server != NULL) g_free(uri->server);
+    uri->server = NULL;
+    if (uri->user != NULL) g_free(uri->user);
+    uri->user = NULL;
+    if (uri->path != NULL) g_free(uri->path);
+    uri->path = NULL;
+    if (uri->fragment != NULL) g_free(uri->fragment);
+    uri->fragment = NULL;
+    if (uri->opaque != NULL) g_free(uri->opaque);
+    uri->opaque = NULL;
+    if (uri->authority != NULL) g_free(uri->authority);
+    uri->authority = NULL;
+    if (uri->query != NULL) g_free(uri->query);
+    uri->query = NULL;
+}
+
+/**
+ * uri_free:
+ * @uri:  pointer to an URI
+ *
+ * Free up the URI struct
+ */
+void
+uri_free(URI *uri) {
+    uri_clean(uri);
+    g_free(uri);
+}
+
+/************************************************************************
+ *									*
+ *			Helper functions				*
+ *									*
+ ************************************************************************/
+
+/**
+ * normalize_uri_path:
+ * @path:  pointer to the path string
+ *
+ * Applies the 5 normalization steps to a path string--that is, RFC 2396
+ * Section 5.2, steps 6.c through 6.g.
+ *
+ * Normalization occurs directly on the string, no new allocation is done
+ *
+ * Returns 0 or an error code
+ */
+static int
+normalize_uri_path(char *path) {
+    char *cur, *out;
+
+    if (path == NULL)
+	return(-1);
+
+    /* Skip all initial "/" chars.  We want to get to the beginning of the
+     * first non-empty segment.
+     */
+    cur = path;
+    while (cur[0] == '/')
+      ++cur;
+    if (cur[0] == '\0')
+      return(0);
+
+    /* Keep everything we've seen so far.  */
+    out = cur;
+
+    /*
+     * Analyze each segment in sequence for cases (c) and (d).
+     */
+    while (cur[0] != '\0') {
+	/*
+	 * c) All occurrences of "./", where "." is a complete path segment,
+	 *    are removed from the buffer string.
+	 */
+	if ((cur[0] == '.') && (cur[1] == '/')) {
+	    cur += 2;
+	    /* '//' normalization should be done at this point too */
+	    while (cur[0] == '/')
+		cur++;
+	    continue;
+	}
+
+	/*
+	 * d) If the buffer string ends with "." as a complete path segment,
+	 *    that "." is removed.
+	 */
+	if ((cur[0] == '.') && (cur[1] == '\0'))
+	    break;
+
+	/* Otherwise keep the segment.  */
+	while (cur[0] != '/') {
+            if (cur[0] == '\0')
+              goto done_cd;
+	    (out++)[0] = (cur++)[0];
+	}
+	/* nomalize // */
+	while ((cur[0] == '/') && (cur[1] == '/'))
+	    cur++;
+
+        (out++)[0] = (cur++)[0];
+    }
+ done_cd:
+    out[0] = '\0';
+
+    /* Reset to the beginning of the first segment for the next sequence.  */
+    cur = path;
+    while (cur[0] == '/')
+      ++cur;
+    if (cur[0] == '\0')
+	return(0);
+
+    /*
+     * Analyze each segment in sequence for cases (e) and (f).
+     *
+     * e) All occurrences of "<segment>/../", where <segment> is a
+     *    complete path segment not equal to "..", are removed from the
+     *    buffer string.  Removal of these path segments is performed
+     *    iteratively, removing the leftmost matching pattern on each
+     *    iteration, until no matching pattern remains.
+     *
+     * f) If the buffer string ends with "<segment>/..", where <segment>
+     *    is a complete path segment not equal to "..", that
+     *    "<segment>/.." is removed.
+     *
+     * To satisfy the "iterative" clause in (e), we need to collapse the
+     * string every time we find something that needs to be removed.  Thus,
+     * we don't need to keep two pointers into the string: we only need a
+     * "current position" pointer.
+     */
+    while (1) {
+        char *segp, *tmp;
+
+        /* At the beginning of each iteration of this loop, "cur" points to
+         * the first character of the segment we want to examine.
+         */
+
+        /* Find the end of the current segment.  */
+        segp = cur;
+        while ((segp[0] != '/') && (segp[0] != '\0'))
+          ++segp;
+
+        /* If this is the last segment, we're done (we need at least two
+         * segments to meet the criteria for the (e) and (f) cases).
+         */
+        if (segp[0] == '\0')
+          break;
+
+        /* If the first segment is "..", or if the next segment _isn't_ "..",
+         * keep this segment and try the next one.
+         */
+        ++segp;
+        if (((cur[0] == '.') && (cur[1] == '.') && (segp == cur+3))
+            || ((segp[0] != '.') || (segp[1] != '.')
+                || ((segp[2] != '/') && (segp[2] != '\0')))) {
+          cur = segp;
+          continue;
+        }
+
+        /* If we get here, remove this segment and the next one and back up
+         * to the previous segment (if there is one), to implement the
+         * "iteratively" clause.  It's pretty much impossible to back up
+         * while maintaining two pointers into the buffer, so just compact
+         * the whole buffer now.
+         */
+
+        /* If this is the end of the buffer, we're done.  */
+        if (segp[2] == '\0') {
+          cur[0] = '\0';
+          break;
+        }
+        /* Valgrind complained, strcpy(cur, segp + 3); */
+        /* string will overlap, do not use strcpy */
+        tmp = cur;
+        segp += 3;
+        while ((*tmp++ = *segp++) != 0)
+          ;
+
+        /* If there are no previous segments, then keep going from here.  */
+        segp = cur;
+        while ((segp > path) && ((--segp)[0] == '/'))
+          ;
+        if (segp == path)
+          continue;
+
+        /* "segp" is pointing to the end of a previous segment; find it's
+         * start.  We need to back up to the previous segment and start
+         * over with that to handle things like "foo/bar/../..".  If we
+         * don't do this, then on the first pass we'll remove the "bar/..",
+         * but be pointing at the second ".." so we won't realize we can also
+         * remove the "foo/..".
+         */
+        cur = segp;
+        while ((cur > path) && (cur[-1] != '/'))
+          --cur;
+    }
+    out[0] = '\0';
+
+    /*
+     * g) If the resulting buffer string still begins with one or more
+     *    complete path segments of "..", then the reference is
+     *    considered to be in error. Implementations may handle this
+     *    error by retaining these components in the resolved path (i.e.,
+     *    treating them as part of the final URI), by removing them from
+     *    the resolved path (i.e., discarding relative levels above the
+     *    root), or by avoiding traversal of the reference.
+     *
+     * We discard them from the final path.
+     */
+    if (path[0] == '/') {
+      cur = path;
+      while ((cur[0] == '/') && (cur[1] == '.') && (cur[2] == '.')
+             && ((cur[3] == '/') || (cur[3] == '\0')))
+	cur += 3;
+
+      if (cur != path) {
+	out = path;
+	while (cur[0] != '\0')
+          (out++)[0] = (cur++)[0];
+	out[0] = 0;
+      }
+    }
+
+    return(0);
+}
+
+static int is_hex(char c) {
+    if (((c >= '0') && (c <= '9')) ||
+        ((c >= 'a') && (c <= 'f')) ||
+        ((c >= 'A') && (c <= 'F')))
+	return(1);
+    return(0);
+}
+
+
+/**
+ * uri_string_unescape:
+ * @str:  the string to unescape
+ * @len:   the length in bytes to unescape (or <= 0 to indicate full string)
+ * @target:  optional destination buffer
+ *
+ * Unescaping routine, but does not check that the string is an URI. The
+ * output is a direct unsigned char translation of %XX values (no encoding)
+ * Note that the length of the result can only be smaller or same size as
+ * the input string.
+ *
+ * Returns a copy of the string, but unescaped, will return NULL only in case
+ * of error
+ */
+char *
+uri_string_unescape(const char *str, int len, char *target) {
+    char *ret, *out;
+    const char *in;
+
+    if (str == NULL)
+	return(NULL);
+    if (len <= 0) len = strlen(str);
+    if (len < 0) return(NULL);
+
+    if (target == NULL) {
+	ret = g_malloc(len + 1);
+    } else
+	ret = target;
+    in = str;
+    out = ret;
+    while(len > 0) {
+	if ((len > 2) && (*in == '%') && (is_hex(in[1])) && (is_hex(in[2]))) {
+	    in++;
+	    if ((*in >= '0') && (*in <= '9'))
+	        *out = (*in - '0');
+	    else if ((*in >= 'a') && (*in <= 'f'))
+	        *out = (*in - 'a') + 10;
+	    else if ((*in >= 'A') && (*in <= 'F'))
+	        *out = (*in - 'A') + 10;
+	    in++;
+	    if ((*in >= '0') && (*in <= '9'))
+	        *out = *out * 16 + (*in - '0');
+	    else if ((*in >= 'a') && (*in <= 'f'))
+	        *out = *out * 16 + (*in - 'a') + 10;
+	    else if ((*in >= 'A') && (*in <= 'F'))
+	        *out = *out * 16 + (*in - 'A') + 10;
+	    in++;
+	    len -= 3;
+	    out++;
+	} else {
+	    *out++ = *in++;
+	    len--;
+	}
+    }
+    *out = 0;
+    return(ret);
+}
+
+/**
+ * uri_string_escape:
+ * @str:  string to escape
+ * @list: exception list string of chars not to escape
+ *
+ * This routine escapes a string to hex, ignoring reserved characters (a-z)
+ * and the characters in the exception list.
+ *
+ * Returns a new escaped string or NULL in case of error.
+ */
+char *
+uri_string_escape(const char *str, const char *list) {
+    char *ret, ch;
+    char *temp;
+    const char *in;
+    int len, out;
+
+    if (str == NULL)
+	return(NULL);
+    if (str[0] == 0)
+	return(g_strdup(str));
+    len = strlen(str);
+    if (!(len > 0)) return(NULL);
+
+    len += 20;
+    ret = g_malloc(len);
+    in = str;
+    out = 0;
+    while(*in != 0) {
+	if (len - out <= 3) {
+            temp = realloc2n(ret, &len);
+	    ret = temp;
+	}
+
+	ch = *in;
+
+	if ((ch != '@') && (!IS_UNRESERVED(ch)) && (!strchr(list, ch))) {
+	    unsigned char val;
+	    ret[out++] = '%';
+	    val = ch >> 4;
+	    if (val <= 9)
+		ret[out++] = '0' + val;
+	    else
+		ret[out++] = 'A' + val - 0xA;
+	    val = ch & 0xF;
+	    if (val <= 9)
+		ret[out++] = '0' + val;
+	    else
+		ret[out++] = 'A' + val - 0xA;
+	    in++;
+	} else {
+	    ret[out++] = *in++;
+	}
+
+    }
+    ret[out] = 0;
+    return(ret);
+}
+
+/************************************************************************
+ *									*
+ *			Public functions				*
+ *									*
+ ************************************************************************/
+
+/**
+ * uri_resolve:
+ * @URI:  the URI instance found in the document
+ * @base:  the base value
+ *
+ * Computes he final URI of the reference done by checking that
+ * the given URI is valid, and building the final URI using the
+ * base URI. This is processed according to section 5.2 of the
+ * RFC 2396
+ *
+ * 5.2. Resolving Relative References to Absolute Form
+ *
+ * Returns a new URI string (to be freed by the caller) or NULL in case
+ *         of error.
+ */
+char *
+uri_resolve(const char *uri, const char *base) {
+    char *val = NULL;
+    int ret, len, indx, cur, out;
+    URI *ref = NULL;
+    URI *bas = NULL;
+    URI *res = NULL;
+
+    /*
+     * 1) The URI reference is parsed into the potential four components and
+     *    fragment identifier, as described in Section 4.3.
+     *
+     *    NOTE that a completely empty URI is treated by modern browsers
+     *    as a reference to "." rather than as a synonym for the current
+     *    URI.  Should we do that here?
+     */
+    if (uri == NULL)
+	ret = -1;
+    else {
+	if (*uri) {
+	    ref = uri_new();
+	    if (ref == NULL)
+		goto done;
+	    ret = uri_parse_into(ref, uri);
+	}
+	else
+	    ret = 0;
+    }
+    if (ret != 0)
+	goto done;
+    if ((ref != NULL) && (ref->scheme != NULL)) {
+	/*
+	 * The URI is absolute don't modify.
+	 */
+	val = g_strdup(uri);
+	goto done;
+    }
+    if (base == NULL)
+	ret = -1;
+    else {
+	bas = uri_new();
+	if (bas == NULL)
+	    goto done;
+	ret = uri_parse_into(bas, base);
+    }
+    if (ret != 0) {
+	if (ref)
+	    val = uri_to_string(ref);
+	goto done;
+    }
+    if (ref == NULL) {
+	/*
+	 * the base fragment must be ignored
+	 */
+	if (bas->fragment != NULL) {
+	    g_free(bas->fragment);
+	    bas->fragment = NULL;
+	}
+	val = uri_to_string(bas);
+	goto done;
+    }
+
+    /*
+     * 2) If the path component is empty and the scheme, authority, and
+     *    query components are undefined, then it is a reference to the
+     *    current document and we are done.  Otherwise, the reference URI's
+     *    query and fragment components are defined as found (or not found)
+     *    within the URI reference and not inherited from the base URI.
+     *
+     *    NOTE that in modern browsers, the parsing differs from the above
+     *    in the following aspect:  the query component is allowed to be
+     *    defined while still treating this as a reference to the current
+     *    document.
+     */
+    res = uri_new();
+    if (res == NULL)
+	goto done;
+    if ((ref->scheme == NULL) && (ref->path == NULL) &&
+	((ref->authority == NULL) && (ref->server == NULL))) {
+	if (bas->scheme != NULL)
+	    res->scheme = g_strdup(bas->scheme);
+	if (bas->authority != NULL)
+	    res->authority = g_strdup(bas->authority);
+	else if (bas->server != NULL) {
+	    res->server = g_strdup(bas->server);
+	    if (bas->user != NULL)
+		res->user = g_strdup(bas->user);
+	    res->port = bas->port;
+	}
+	if (bas->path != NULL)
+	    res->path = g_strdup(bas->path);
+	if (ref->query != NULL)
+	    res->query = g_strdup (ref->query);
+	else if (bas->query != NULL)
+	    res->query = g_strdup(bas->query);
+	if (ref->fragment != NULL)
+	    res->fragment = g_strdup(ref->fragment);
+	goto step_7;
+    }
+
+    /*
+     * 3) If the scheme component is defined, indicating that the reference
+     *    starts with a scheme name, then the reference is interpreted as an
+     *    absolute URI and we are done.  Otherwise, the reference URI's
+     *    scheme is inherited from the base URI's scheme component.
+     */
+    if (ref->scheme != NULL) {
+	val = uri_to_string(ref);
+	goto done;
+    }
+    if (bas->scheme != NULL)
+	res->scheme = g_strdup(bas->scheme);
+
+    if (ref->query != NULL)
+	res->query = g_strdup(ref->query);
+    if (ref->fragment != NULL)
+	res->fragment = g_strdup(ref->fragment);
+
+    /*
+     * 4) If the authority component is defined, then the reference is a
+     *    network-path and we skip to step 7.  Otherwise, the reference
+     *    URI's authority is inherited from the base URI's authority
+     *    component, which will also be undefined if the URI scheme does not
+     *    use an authority component.
+     */
+    if ((ref->authority != NULL) || (ref->server != NULL)) {
+	if (ref->authority != NULL)
+	    res->authority = g_strdup(ref->authority);
+	else {
+	    res->server = g_strdup(ref->server);
+	    if (ref->user != NULL)
+		res->user = g_strdup(ref->user);
+            res->port = ref->port;
+	}
+	if (ref->path != NULL)
+	    res->path = g_strdup(ref->path);
+	goto step_7;
+    }
+    if (bas->authority != NULL)
+	res->authority = g_strdup(bas->authority);
+    else if (bas->server != NULL) {
+	res->server = g_strdup(bas->server);
+	if (bas->user != NULL)
+	    res->user = g_strdup(bas->user);
+	res->port = bas->port;
+    }
+
+    /*
+     * 5) If the path component begins with a slash character ("/"), then
+     *    the reference is an absolute-path and we skip to step 7.
+     */
+    if ((ref->path != NULL) && (ref->path[0] == '/')) {
+	res->path = g_strdup(ref->path);
+	goto step_7;
+    }
+
+
+    /*
+     * 6) If this step is reached, then we are resolving a relative-path
+     *    reference.  The relative path needs to be merged with the base
+     *    URI's path.  Although there are many ways to do this, we will
+     *    describe a simple method using a separate string buffer.
+     *
+     * Allocate a buffer large enough for the result string.
+     */
+    len = 2; /* extra / and 0 */
+    if (ref->path != NULL)
+	len += strlen(ref->path);
+    if (bas->path != NULL)
+	len += strlen(bas->path);
+    res->path = g_malloc(len);
+    res->path[0] = 0;
+
+    /*
+     * a) All but the last segment of the base URI's path component is
+     *    copied to the buffer.  In other words, any characters after the
+     *    last (right-most) slash character, if any, are excluded.
+     */
+    cur = 0;
+    out = 0;
+    if (bas->path != NULL) {
+	while (bas->path[cur] != 0) {
+	    while ((bas->path[cur] != 0) && (bas->path[cur] != '/'))
+		cur++;
+	    if (bas->path[cur] == 0)
+		break;
+
+	    cur++;
+	    while (out < cur) {
+		res->path[out] = bas->path[out];
+		out++;
+	    }
+	}
+    }
+    res->path[out] = 0;
+
+    /*
+     * b) The reference's path component is appended to the buffer
+     *    string.
+     */
+    if (ref->path != NULL && ref->path[0] != 0) {
+	indx = 0;
+	/*
+	 * Ensure the path includes a '/'
+	 */
+	if ((out == 0) && (bas->server != NULL))
+	    res->path[out++] = '/';
+	while (ref->path[indx] != 0) {
+	    res->path[out++] = ref->path[indx++];
+	}
+    }
+    res->path[out] = 0;
+
+    /*
+     * Steps c) to h) are really path normalization steps
+     */
+    normalize_uri_path(res->path);
+
+step_7:
+
+    /*
+     * 7) The resulting URI components, including any inherited from the
+     *    base URI, are recombined to give the absolute form of the URI
+     *    reference.
+     */
+    val = uri_to_string(res);
+
+done:
+    if (ref != NULL)
+	uri_free(ref);
+    if (bas != NULL)
+	uri_free(bas);
+    if (res != NULL)
+	uri_free(res);
+    return(val);
+}
+
+/**
+ * uri_resolve_relative:
+ * @URI:  the URI reference under consideration
+ * @base:  the base value
+ *
+ * Expresses the URI of the reference in terms relative to the
+ * base.  Some examples of this operation include:
+ *     base = "http://site1.com/docs/book1.html"
+ *        URI input                        URI returned
+ *     docs/pic1.gif                    pic1.gif
+ *     docs/img/pic1.gif                img/pic1.gif
+ *     img/pic1.gif                     ../img/pic1.gif
+ *     http://site1.com/docs/pic1.gif   pic1.gif
+ *     http://site2.com/docs/pic1.gif   http://site2.com/docs/pic1.gif
+ *
+ *     base = "docs/book1.html"
+ *        URI input                        URI returned
+ *     docs/pic1.gif                    pic1.gif
+ *     docs/img/pic1.gif                img/pic1.gif
+ *     img/pic1.gif                     ../img/pic1.gif
+ *     http://site1.com/docs/pic1.gif   http://site1.com/docs/pic1.gif
+ *
+ *
+ * Note: if the URI reference is really wierd or complicated, it may be
+ *       worthwhile to first convert it into a "nice" one by calling
+ *       uri_resolve (using 'base') before calling this routine,
+ *       since this routine (for reasonable efficiency) assumes URI has
+ *       already been through some validation.
+ *
+ * Returns a new URI string (to be freed by the caller) or NULL in case
+ * error.
+ */
+char *
+uri_resolve_relative (const char *uri, const char * base)
+{
+    char *val = NULL;
+    int ret;
+    int ix;
+    int pos = 0;
+    int nbslash = 0;
+    int len;
+    URI *ref = NULL;
+    URI *bas = NULL;
+    char *bptr, *uptr, *vptr;
+    int remove_path = 0;
+
+    if ((uri == NULL) || (*uri == 0))
+	return NULL;
+
+    /*
+     * First parse URI into a standard form
+     */
+    ref = uri_new ();
+    if (ref == NULL)
+	return NULL;
+    /* If URI not already in "relative" form */
+    if (uri[0] != '.') {
+	ret = uri_parse_into (ref, uri);
+	if (ret != 0)
+	    goto done;		/* Error in URI, return NULL */
+    } else
+	ref->path = g_strdup(uri);
+
+    /*
+     * Next parse base into the same standard form
+     */
+    if ((base == NULL) || (*base == 0)) {
+	val = g_strdup (uri);
+	goto done;
+    }
+    bas = uri_new ();
+    if (bas == NULL)
+	goto done;
+    if (base[0] != '.') {
+	ret = uri_parse_into (bas, base);
+	if (ret != 0)
+	    goto done;		/* Error in base, return NULL */
+    } else
+	bas->path = g_strdup(base);
+
+    /*
+     * If the scheme / server on the URI differs from the base,
+     * just return the URI
+     */
+    if ((ref->scheme != NULL) &&
+	((bas->scheme == NULL) ||
+	 (strcmp (bas->scheme, ref->scheme)) ||
+	 (strcmp (bas->server, ref->server)))) {
+	val = g_strdup (uri);
+	goto done;
+    }
+    if (!strcmp(bas->path, ref->path)) {
+	val = g_strdup("");
+	goto done;
+    }
+    if (bas->path == NULL) {
+	val = g_strdup(ref->path);
+	goto done;
+    }
+    if (ref->path == NULL) {
+        ref->path = (char *) "/";
+	remove_path = 1;
+    }
+
+    /*
+     * At this point (at last!) we can compare the two paths
+     *
+     * First we take care of the special case where either of the
+     * two path components may be missing (bug 316224)
+     */
+    if (bas->path == NULL) {
+	if (ref->path != NULL) {
+	    uptr = ref->path;
+	    if (*uptr == '/')
+		uptr++;
+	    /* exception characters from uri_to_string */
+	    val = uri_string_escape(uptr, "/;&=+$,");
+	}
+	goto done;
+    }
+    bptr = bas->path;
+    if (ref->path == NULL) {
+	for (ix = 0; bptr[ix] != 0; ix++) {
+	    if (bptr[ix] == '/')
+		nbslash++;
+	}
+	uptr = NULL;
+	len = 1;	/* this is for a string terminator only */
+    } else {
+    /*
+     * Next we compare the two strings and find where they first differ
+     */
+	if ((ref->path[pos] == '.') && (ref->path[pos+1] == '/'))
+            pos += 2;
+	if ((*bptr == '.') && (bptr[1] == '/'))
+            bptr += 2;
+	else if ((*bptr == '/') && (ref->path[pos] != '/'))
+	    bptr++;
+	while ((bptr[pos] == ref->path[pos]) && (bptr[pos] != 0))
+	    pos++;
+
+	if (bptr[pos] == ref->path[pos]) {
+	    val = g_strdup("");
+	    goto done;		/* (I can't imagine why anyone would do this) */
+	}
+
+	/*
+	 * In URI, "back up" to the last '/' encountered.  This will be the
+	 * beginning of the "unique" suffix of URI
+	 */
+	ix = pos;
+	if ((ref->path[ix] == '/') && (ix > 0))
+	    ix--;
+	else if ((ref->path[ix] == 0) && (ix > 1) && (ref->path[ix - 1] == '/'))
+	    ix -= 2;
+	for (; ix > 0; ix--) {
+	    if (ref->path[ix] == '/')
+		break;
+	}
+	if (ix == 0) {
+	    uptr = ref->path;
+	} else {
+	    ix++;
+	    uptr = &ref->path[ix];
+	}
+
+	/*
+	 * In base, count the number of '/' from the differing point
+	 */
+	if (bptr[pos] != ref->path[pos]) {/* check for trivial URI == base */
+	    for (; bptr[ix] != 0; ix++) {
+		if (bptr[ix] == '/')
+		    nbslash++;
+	    }
+	}
+	len = strlen (uptr) + 1;
+    }
+
+    if (nbslash == 0) {
+	if (uptr != NULL)
+	    /* exception characters from uri_to_string */
+	    val = uri_string_escape(uptr, "/;&=+$,");
+	goto done;
+    }
+
+    /*
+     * Allocate just enough space for the returned string -
+     * length of the remainder of the URI, plus enough space
+     * for the "../" groups, plus one for the terminator
+     */
+    val = g_malloc (len + 3 * nbslash);
+    vptr = val;
+    /*
+     * Put in as many "../" as needed
+     */
+    for (; nbslash>0; nbslash--) {
+	*vptr++ = '.';
+	*vptr++ = '.';
+	*vptr++ = '/';
+    }
+    /*
+     * Finish up with the end of the URI
+     */
+    if (uptr != NULL) {
+        if ((vptr > val) && (len > 0) &&
+	    (uptr[0] == '/') && (vptr[-1] == '/')) {
+	    memcpy (vptr, uptr + 1, len - 1);
+	    vptr[len - 2] = 0;
+	} else {
+	    memcpy (vptr, uptr, len);
+	    vptr[len - 1] = 0;
+	}
+    } else {
+	vptr[len - 1] = 0;
+    }
+
+    /* escape the freshly-built path */
+    vptr = val;
+	/* exception characters from uri_to_string */
+    val = uri_string_escape(vptr, "/;&=+$,");
+    g_free(vptr);
+
+done:
+    /*
+     * Free the working variables
+     */
+    if (remove_path != 0)
+        ref->path = NULL;
+    if (ref != NULL)
+	uri_free (ref);
+    if (bas != NULL)
+	uri_free (bas);
+
+    return val;
+}
+
+/*
+ * Utility functions to help parse and assemble query strings.
+ */
+
+struct QueryParams *
+query_params_new (int init_alloc)
+{
+    struct QueryParams *ps;
+
+    if (init_alloc <= 0) init_alloc = 1;
+
+    ps = g_new(QueryParams, 1);
+    ps->n = 0;
+    ps->alloc = init_alloc;
+    ps->p = g_new(QueryParam, ps->alloc);
+
+    return ps;
+}
+
+/* Ensure there is space to store at least one more parameter
+ * at the end of the set.
+ */
+static int
+query_params_append (struct QueryParams *ps,
+               const char *name, const char *value)
+{
+    if (ps->n >= ps->alloc) {
+        ps->p = g_renew(QueryParam, ps->p, ps->alloc * 2);
+        ps->alloc *= 2;
+    }
+
+    ps->p[ps->n].name = g_strdup(name);
+    ps->p[ps->n].value = value ? g_strdup(value) : NULL;
+    ps->p[ps->n].ignore = 0;
+    ps->n++;
+
+    return 0;
+}
+
+void
+query_params_free (struct QueryParams *ps)
+{
+    int i;
+
+    for (i = 0; i < ps->n; ++i) {
+        g_free (ps->p[i].name);
+        g_free (ps->p[i].value);
+    }
+    g_free (ps->p);
+    g_free (ps);
+}
+
+struct QueryParams *
+query_params_parse (const char *query)
+{
+    struct QueryParams *ps;
+    const char *end, *eq;
+
+    ps = query_params_new (0);
+    if (!query || query[0] == '\0') return ps;
+
+    while (*query) {
+        char *name = NULL, *value = NULL;
+
+        /* Find the next separator, or end of the string. */
+        end = strchr (query, '&');
+        if (!end)
+            end = strchr (query, ';');
+        if (!end)
+            end = query + strlen (query);
+
+        /* Find the first '=' character between here and end. */
+        eq = strchr (query, '=');
+        if (eq && eq >= end) eq = NULL;
+
+        /* Empty section (eg. "&&"). */
+        if (end == query)
+            goto next;
+
+        /* If there is no '=' character, then we have just "name"
+         * and consistent with CGI.pm we assume value is "".
+         */
+        else if (!eq) {
+            name = uri_string_unescape (query, end - query, NULL);
+            value = NULL;
+        }
+        /* Or if we have "name=" here (works around annoying
+         * problem when calling uri_string_unescape with len = 0).
+         */
+        else if (eq+1 == end) {
+            name = uri_string_unescape (query, eq - query, NULL);
+            value = g_new0(char, 1);
+        }
+        /* If the '=' character is at the beginning then we have
+         * "=value" and consistent with CGI.pm we _ignore_ this.
+         */
+        else if (query == eq)
+            goto next;
+
+        /* Otherwise it's "name=value". */
+        else {
+            name = uri_string_unescape (query, eq - query, NULL);
+            value = uri_string_unescape (eq+1, end - (eq+1), NULL);
+        }
+
+        /* Append to the parameter set. */
+        query_params_append (ps, name, value);
+        g_free(name);
+        g_free(value);
+
+    next:
+        query = end;
+        if (*query) query ++; /* skip '&' separator */
+    }
+
+    return ps;
+}
diff --git a/uri.h b/uri.h
new file mode 100644
index 0000000..de99b3b
--- /dev/null
+++ b/uri.h
@@ -0,0 +1,113 @@ 
+/**
+ * Summary: library of generic URI related routines
+ * Description: library of generic URI related routines
+ *              Implements RFC 2396
+ *
+ * Copyright (C) 1998-2003 Daniel Veillard.  All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE
+ * DANIEL VEILLARD BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+ * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * Except as contained in this notice, the name of Daniel Veillard shall not
+ * be used in advertising or otherwise to promote the sale, use or other
+ * dealings in this Software without prior written authorization from him.
+ *
+ * Author: Daniel Veillard
+ **
+ * Copyright (C) 2007 Red Hat, Inc.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307  USA
+ *
+ * Authors:
+ *    Richard W.M. Jones <rjones@redhat.com>
+ *
+ * Utility functions to help parse and assemble query strings.
+ */
+
+#ifndef QEMU_URI_H
+#define QEMU_URI_H
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/**
+ * URI:
+ *
+ * A parsed URI reference. This is a struct containing the various fields
+ * as described in RFC 2396 but separated for further processing.
+ */
+typedef struct URI {
+    char *scheme;	/* the URI scheme */
+    char *opaque;	/* opaque part */
+    char *authority;	/* the authority part */
+    char *server;	/* the server part */
+    char *user;		/* the user part */
+    int port;		/* the port number */
+    char *path;		/* the path string */
+    char *fragment;	/* the fragment identifier */
+    int  cleanup;	/* parsing potentially unclean URI */
+    char *query;	/* the query string (as it appears in the URI) */
+} URI;
+
+URI *uri_new(void);
+char *uri_resolve(const char *URI, const char *base);
+char *uri_resolve_relative(const char *URI, const char *base);
+URI *uri_parse(const char *str);
+URI *uri_parse_raw(const char *str, int raw);
+int uri_parse_into(URI *uri, const char *str);
+char *uri_to_string(URI *uri);
+char *uri_string_escape(const char *str, const char *list);
+char *uri_string_unescape(const char *str, int len, char *target);
+void uri_free(URI *uri);
+
+/* Single web service query parameter 'name=value'. */
+typedef struct QueryParam {
+  char *name;			/* Name (unescaped). */
+  char *value;			/* Value (unescaped). */
+  int ignore;			/* Ignore this field in qparam_get_query */
+} QueryParam;
+
+/* Set of parameters. */
+typedef struct QueryParams {
+  int n;			/* number of parameters used */
+  int alloc;			/* allocated space */
+  QueryParam *p;		/* array of parameters */
+} QueryParams;
+
+struct QueryParams *query_params_new (int init_alloc);
+int query_param_append (QueryParams *ps, const char *name, const char *value);
+extern char *query_param_to_string (const QueryParams *ps);
+extern QueryParams *query_params_parse (const char *query);
+extern void query_params_free (QueryParams *ps);
+
+#ifdef __cplusplus
+}
+#endif
+#endif /* QEMU_URI_H */