Patchwork [v10,3/5] qemu: URI parsing library

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Submitter Bharata B Rao
Date Sept. 27, 2012, 1:58 p.m.
Message ID <20120927135843.GG18285@in.ibm.com>
Download mbox | patch
Permalink /patch/187371/
State New
Headers show

Comments

Bharata B Rao - Sept. 27, 2012, 1:58 p.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
Daniel P. Berrange - Sept. 27, 2012, 2:36 p.m.
On Thu, Sep 27, 2012 at 07:28:43PM +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.
> 
> 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 +++

IMHO, you should also be importing the URI code test suite from libvirt
to verify that the way you merged/changed the codebases did not break
anything.

Daniel
Paolo Bonzini - Sept. 27, 2012, 3:55 p.m.
Il 27/09/2012 16:36, Daniel P. Berrange ha scritto:
>> > 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 +++
> IMHO, you should also be importing the URI code test suite from libvirt
> to verify that the way you merged/changed the codebases did not break
> anything.

Yes, can be done separately though.

Paolo
Daniel P. Berrange - Sept. 28, 2012, 8:39 a.m.
On Thu, Sep 27, 2012 at 05:55:15PM +0200, Paolo Bonzini wrote:
> Il 27/09/2012 16:36, Daniel P. Berrange ha scritto:
> >> > 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 +++
> > IMHO, you should also be importing the URI code test suite from libvirt
> > to verify that the way you merged/changed the codebases did not break
> > anything.
> 
> Yes, can be done separately though.

In this case I disagree.  The URI parsing code here is complex enough that
I don't think any reviewer can credibly claim to spot flaws that might
have been introduced when combing the libvirt + libxml2 URI code parts.
A test suite is the only way to validate this kind of complex code IMHO
and so should be included in this patch.

Daniel
Paolo Bonzini - Sept. 28, 2012, 9:47 a.m.
Il 28/09/2012 10:39, Daniel P. Berrange ha scritto:
>>> > > IMHO, you should also be importing the URI code test suite from libvirt
>>> > > to verify that the way you merged/changed the codebases did not break
>>> > > anything.
>> > 
>> > Yes, can be done separately though.
> In this case I disagree.  The URI parsing code here is complex enough that
> I don't think any reviewer can credibly claim to spot flaws that might
> have been introduced when combing the libvirt + libxml2 URI code parts.
> A test suite is the only way to validate this kind of complex code IMHO
> and so should be included in this patch.

The libvirt testsuite has ~10 testcases for URI, one of them for
IPv6-specific behavior that is not part of uri.c, and 13 for parsing
query parameters.  At least for the URI part, this would be false safety.

FWIW, this is what I had "tested" the code with:

void test(const char *x)
{
    URI *uri = uri_parse(x);
    QueryParams *qp;
    char *out;

    if (!uri) {
        printf ("INVALID: %s\n", x);
        return;
    }

    /* Escape the parameters.  */
    qp = query_params_parse(uri->query);
    g_free(uri->query);
    uri->query = query_params_to_string(qp);
    query_params_free(qp);

    out = uri_to_string(uri);
    uri_free(uri);
    printf("VALID: %s\n", out);
    g_free(out);
}

int main()
{
    test("gluster+unix:///b?c=d");
    test("gluster+tcp://user:pwd@foo:80/b?c=d");
    test("gluster+tcp://user:pwd@foo:8b0/b?c=d");
    test("http://a/b?c=d");
    test("http://a/b?c=/d/e");
    test("http://a/b?c=/d/e&f");
    test("http://a/b?c=/d/e&f=&&ggg");
    return 0;
}

Paolo

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 */