PIKApp/plug-ins/help-browser/uri.c

391 lines
10 KiB
C

/* PIKA - Photo and Image Kooker Application
* a rebranding of The GNU Image Manipulation Program (created with heckimp)
* A derived work which may be trivial. However, any changes may be (C)2023 by Aldercone Studio
*
* Original copyright, applying to most contents (license remains unchanged):
* Copyright (C) 1995 Spencer Kimball and Peter Mattis
*
* The PIKA Help Browser - URI functions
* Copyright (C) 2001 Jacob Schroeder <jacob@convergence.de>
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 3 of the License, or
* (at your option) any later version.
*
* This program 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <https://www.gnu.org/licenses/>.
*/
#include "config.h"
#include <string.h>
#include <glib.h>
#include "uri.h"
/* #define URI_DEBUG 1 */
typedef enum
{
URI_UNKNOWN,
URI_ABSURI,
URI_NETPATH,
URI_ABSPATH,
URI_RELPATH,
URI_QUERY,
URI_EMPTY,
URI_FRAGMENT,
URI_INVALID
} UriType;
static UriType
uri_get_type (const gchar *uri)
{
gchar c;
const gchar *cptr;
UriType type = URI_UNKNOWN;
if (!uri)
return type;
cptr = uri;
c = *cptr++;
if (g_ascii_isalpha (c))
{
type = URI_RELPATH; /* assume relative path */
while ((c = *cptr++))
{
if (g_ascii_isalnum (c) || c == '+' || c == '-' || c == '.')
continue;
if (c == ':')
{
/* it was a scheme */
type = URI_ABSURI;
}
break;
}
}
else
{
switch (c)
{
case '/':
if (*cptr == '/')
{
cptr++;
type = URI_NETPATH;
}
else
{
type = URI_ABSPATH;
}
break;
case '?':
type = URI_QUERY;
break;
case '#':
type = URI_FRAGMENT;
break;
case '\0':
type = URI_EMPTY;
break;
default:
type = URI_RELPATH;
break;
}
}
#ifdef URI_DEBUG
g_print ("uri_get_type (\"%s\") -> ", uri);
switch (type)
{
case URI_UNKNOWN: g_print ("unknown"); break;
case URI_ABSURI: g_print ("absuri"); break;
case URI_NETPATH: g_print ("netpath"); break;
case URI_ABSPATH: g_print ("abspath"); break;
case URI_RELPATH: g_print ("relpath"); break;
case URI_QUERY: g_print ("query"); break;
case URI_EMPTY: g_print ("empty"); break;
case URI_FRAGMENT: g_print ("fragment"); break;
case URI_INVALID: g_print ("invalid"); break;
}
g_print ("\n");
#endif
return type;
}
gchar *
uri_to_abs (const gchar *uri,
const gchar *base_uri)
{
gchar c;
const gchar *cptr;
gchar *retval = NULL;
UriType uri_type = URI_UNKNOWN;
UriType base_type = URI_UNKNOWN;
gint base_cnt = 0; /* no of chars to be copied from base URI */
gint uri_cnt = 0; /* no of chars to be copied from URI */
gint sep_cnt = 0; /* no of chars to be inserted between them */
const gchar *sep_str = ""; /* string to insert between base and uri */
const gchar *part;
const gchar *last_segment = NULL;
#ifdef URI_DEBUG
g_print ("uri_to_abs (\"%s\", \"%s\")\n", uri, base_uri);
#endif
/* this function does not use the algorithm that is being proposed
* in RFC 2396. Instead it analyses the first characters of each
* URI to determine its kind (abs, net, path, ...).
* After that it locates the missing parts in the base URI and then
* concats everything into a newly allocated string.
*/
/* determine the kind of the URIs */
uri_type = uri_get_type (uri);
if (uri_type != URI_ABSURI)
{
base_type = uri_get_type (base_uri);
if (base_type != URI_ABSURI)
return NULL; /* neither uri nor base uri are absolute */
}
/* find missing parts in base URI */
switch (uri_type)
{
case URI_ABSURI:
/* base uri not needed */
break;
case URI_QUERY:
/* ??? last segment? */
uri_type = URI_RELPATH;
case URI_NETPATH: /* base scheme */
case URI_ABSPATH: /* base scheme and authority */
case URI_RELPATH: /* base scheme, authority and path */
cptr = base_uri;
/* skip scheme */
while ((c = *cptr++) && c != ':')
; /* nada */
base_cnt = cptr - base_uri; /* incl : */
if (*cptr != '/')
{
/* completion not possible */
return NULL;
}
if (uri_type == URI_NETPATH)
break;
/* skip authority */
if (cptr[0] == '/' && cptr[1] == '/')
{
part = cptr;
cptr += 2;
while ((c = *cptr++) && c != '/' && c != '?' && c != '#')
; /* nada */
cptr--;
base_cnt += cptr - part;
}
if (uri_type == URI_ABSPATH)
break;
/* skip path */
if (*cptr != '/')
{
sep_cnt = 1;
sep_str = "/";
break;
}
part = cptr;
g_assert (*cptr == '/');
while ((c = *cptr++) && c != '?' && c != '#')
{
if (c == '/')
last_segment = cptr - 1;
};
g_assert (last_segment);
cptr = last_segment;
while ((c = *uri) && c == '.' && cptr > part)
{
gint shift_segment = 0;
c = uri[1];
if (c == '.' )
{
c = uri[2];
shift_segment = 1;
}
if (c == '/')
{
uri += 2;
}
else if (c == 0 || c == '?' || c == '#')
{
uri += 1;
}
else
{
break;
}
g_assert (*cptr == '/');
if (shift_segment)
{
uri += 1;
while (cptr > part && *--cptr != '/')
; /* nada */
}
}
base_cnt += cptr - part + 1;
break;
case URI_EMPTY:
case URI_FRAGMENT:
/* use whole base uri */
base_cnt = strlen (base_uri);
break;
case URI_UNKNOWN:
case URI_INVALID:
return NULL;
}
/* do not include fragment part from the URI reference */
for (cptr = uri; (c = *cptr) && c != '#'; cptr++)
; /* nada */
uri_cnt = cptr - uri;
/* allocate string and copy characters */
retval = g_new (gchar, base_cnt + sep_cnt + uri_cnt + 1);
if (base_cnt)
strncpy (retval, base_uri, base_cnt);
if (sep_cnt)
strncpy (retval + base_cnt, sep_str, sep_cnt);
if (uri_cnt)
strncpy (retval + base_cnt + sep_cnt, uri, uri_cnt);
retval[base_cnt + sep_cnt + uri_cnt] = '\0';
#ifdef URI_DEBUG
g_print (" -> \"%s\"\n", retval);
#endif
return retval;
}
#if 0
RFC 2396 URI Generic Syntax August 1998
A. Collected BNF for URI
URI-reference = [ absoluteURI | relativeURI ] [ "#" fragment ]
absoluteURI = scheme ":" ( hier_part | opaque_part )
relativeURI = ( net_path | abs_path | rel_path ) [ "?" query ]
hier_part = ( net_path | abs_path ) [ "?" query ]
opaque_part = uric_no_slash *uric
uric_no_slash = unreserved | escaped | ";" | "?" | ":" | "@" |
"&" | "=" | "+" | "$" | ","
net_path = "//" authority [ abs_path ]
abs_path = "/" path_segments
rel_path = rel_segment [ abs_path ]
rel_segment = 1*( unreserved | escaped |
";" | "@" | "&" | "=" | "+" | "$" | "," )
scheme = alpha *( alpha | digit | "+" | "-" | "." )
authority = server | reg_name
reg_name = 1*( unreserved | escaped | "$" | "," |
";" | ":" | "@" | "&" | "=" | "+" )
server = [ [ userinfo "@" ] hostport ]
userinfo = *( unreserved | escaped |
";" | ":" | "&" | "=" | "+" | "$" | "," )
hostport = host [ ":" port ]
host = hostname | IPv4address
hostname = *( domainlabel "." ) toplabel [ "." ]
domainlabel = alphanum | alphanum *( alphanum | "-" ) alphanum
toplabel = alpha | alpha *( alphanum | "-" ) alphanum
IPv4address = 1*digit "." 1*digit "." 1*digit "." 1*digit
port = *digit
path = [ abs_path | opaque_part ]
path_segments = segment *( "/" segment )
segment = *pchar *( ";" param )
param = *pchar
pchar = unreserved | escaped |
":" | "@" | "&" | "=" | "+" | "$" | ","
query = *uric
fragment = *uric
uric = reserved | unreserved | escaped
reserved = ";" | "/" | "?" | ":" | "@" | "&" | "=" | "+" |
"$" | ","
unreserved = alphanum | mark
mark = "-" | "_" | "." | "!" | "~" | "*" | "'" |
"(" | ")"
escaped = "%" hex hex
hex = digit | "A" | "B" | "C" | "D" | "E" | "F" |
"a" | "b" | "c" | "d" | "e" | "f"
alphanum = alpha | digit
alpha = lowalpha | upalpha
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"
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"
digit = "0" | "1" | "2" | "3" | "4" | "5" | "6" | "7" |
"8" | "9"
#endif