1/*
2 * Copyright (c) 2001-2002 Michael David Adams.
3 * All rights reserved.
4 */
5
6/* __START_OF_JASPER_LICENSE__
7 *
8 * JasPer License Version 2.0
9 *
10 * Copyright (c) 2001-2006 Michael David Adams
11 * Copyright (c) 1999-2000 Image Power, Inc.
12 * Copyright (c) 1999-2000 The University of British Columbia
13 *
14 * All rights reserved.
15 *
16 * Permission is hereby granted, free of charge, to any person (the
17 * "User") obtaining a copy of this software and associated documentation
18 * files (the "Software"), to deal in the Software without restriction,
19 * including without limitation the rights to use, copy, modify, merge,
20 * publish, distribute, and/or sell copies of the Software, and to permit
21 * persons to whom the Software is furnished to do so, subject to the
22 * following conditions:
23 *
24 * 1.  The above copyright notices and this permission notice (which
25 * includes the disclaimer below) shall be included in all copies or
26 * substantial portions of the Software.
27 *
28 * 2.  The name of a copyright holder shall not be used to endorse or
29 * promote products derived from the Software without specific prior
30 * written permission.
31 *
32 * THIS DISCLAIMER OF WARRANTY CONSTITUTES AN ESSENTIAL PART OF THIS
33 * LICENSE.  NO USE OF THE SOFTWARE IS AUTHORIZED HEREUNDER EXCEPT UNDER
34 * THIS DISCLAIMER.  THE SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS
35 * "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING
36 * BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
37 * PARTICULAR PURPOSE AND NONINFRINGEMENT OF THIRD PARTY RIGHTS.  IN NO
38 * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, OR ANY SPECIAL
39 * INDIRECT OR CONSEQUENTIAL DAMAGES, OR ANY DAMAGES WHATSOEVER RESULTING
40 * FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT,
41 * NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION
42 * WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.  NO ASSURANCES ARE
43 * PROVIDED BY THE COPYRIGHT HOLDERS THAT THE SOFTWARE DOES NOT INFRINGE
44 * THE PATENT OR OTHER INTELLECTUAL PROPERTY RIGHTS OF ANY OTHER ENTITY.
45 * EACH COPYRIGHT HOLDER DISCLAIMS ANY LIABILITY TO THE USER FOR CLAIMS
46 * BROUGHT BY ANY OTHER ENTITY BASED ON INFRINGEMENT OF INTELLECTUAL
47 * PROPERTY RIGHTS OR OTHERWISE.  AS A CONDITION TO EXERCISING THE RIGHTS
48 * GRANTED HEREUNDER, EACH USER HEREBY ASSUMES SOLE RESPONSIBILITY TO SECURE
49 * ANY OTHER INTELLECTUAL PROPERTY RIGHTS NEEDED, IF ANY.  THE SOFTWARE
50 * IS NOT FAULT-TOLERANT AND IS NOT INTENDED FOR USE IN MISSION-CRITICAL
51 * SYSTEMS, SUCH AS THOSE USED IN THE OPERATION OF NUCLEAR FACILITIES,
52 * AIRCRAFT NAVIGATION OR COMMUNICATION SYSTEMS, AIR TRAFFIC CONTROL
53 * SYSTEMS, DIRECT LIFE SUPPORT MACHINES, OR WEAPONS SYSTEMS, IN WHICH
54 * THE FAILURE OF THE SOFTWARE OR SYSTEM COULD LEAD DIRECTLY TO DEATH,
55 * PERSONAL INJURY, OR SEVERE PHYSICAL OR ENVIRONMENTAL DAMAGE ("HIGH
56 * RISK ACTIVITIES").  THE COPYRIGHT HOLDERS SPECIFICALLY DISCLAIM ANY
57 * EXPRESS OR IMPLIED WARRANTY OF FITNESS FOR HIGH RISK ACTIVITIES.
58 *
59 * __END_OF_JASPER_LICENSE__
60 */
61
62/*
63 * Tag-Value Parser Library
64 *
65 * $Id: jas_tvp.c,v 1.2 2008-05-26 09:40:52 vp153 Exp $
66 */
67
68/******************************************************************************\
69* Includes.
70\******************************************************************************/
71
72#include <assert.h>
73#include <stdio.h>
74#include <ctype.h>
75#include <stdlib.h>
76
77#include "jasper/jas_malloc.h"
78#include "jasper/jas_string.h"
79#include "jasper/jas_tvp.h"
80
81/******************************************************************************\
82* Macros.
83\******************************************************************************/
84
85/* Is the specified character valid for a tag name? */
86#define	JAS_TVP_ISTAG(x) \
87    (isalpha(x) || (x) == '_' || isdigit(x))
88
89/******************************************************************************\
90* Code for creating and destroying a tag-value parser.
91\******************************************************************************/
92
93jas_tvparser_t *jas_tvparser_create(const char *s)
94{
95    jas_tvparser_t *tvp;
96    if (!(tvp = jas_malloc(sizeof(jas_tvparser_t)))) {
97        return 0;
98    }
99    if (!(tvp->buf = jas_strdup(s))) {
100        jas_tvparser_destroy(tvp);
101        return 0;
102    }
103    tvp->pos = tvp->buf;
104    tvp->tag = 0;
105    tvp->val = 0;
106    return tvp;
107}
108
109void jas_tvparser_destroy(jas_tvparser_t *tvp)
110{
111    if (tvp->buf) {
112        jas_free(tvp->buf);
113    }
114    jas_free(tvp);
115}
116
117/******************************************************************************\
118* Main parsing code.
119\******************************************************************************/
120
121/* Get the next tag-value pair. */
122int jas_tvparser_next(jas_tvparser_t *tvp)
123{
124    char *p;
125    char *tag;
126    char *val;
127
128    /* Skip any leading whitespace. */
129    p = tvp->pos;
130    while (*p != '\0' && isspace(*p)) {
131        ++p;
132    }
133
134    /* Has the end of the input data been reached? */
135    if (*p == '\0') {
136        /* No more tags are present. */
137        tvp->pos = p;
138        return 1;
139    }
140
141    /* Does the tag name begin with a valid character? */
142    if (!JAS_TVP_ISTAG(*p)) {
143        return -1;
144    }
145
146    /* Remember where the tag name begins. */
147    tag = p;
148
149    /* Find the end of the tag name. */
150    while (*p != '\0' && JAS_TVP_ISTAG(*p)) {
151        ++p;
152    }
153
154    /* Has the end of the input data been reached? */
155    if (*p == '\0') {
156        /* The value field is empty. */
157        tvp->tag = tag;
158        tvp->val = "";
159        tvp->pos = p;
160        return 0;
161    }
162
163    /* Is a value field not present? */
164    if (*p != '=') {
165        if (*p != '\0' && !isspace(*p)) {
166            return -1;
167        }
168        *p++ = '\0';
169        tvp->tag = tag;
170        tvp->val = "";
171        tvp->pos = p;
172        return 0;
173    }
174
175    *p++ = '\0';
176
177    val = p;
178    while (*p != '\0' && !isspace(*p)) {
179        ++p;
180    }
181
182    if (*p != '\0') {
183        *p++ = '\0';
184    }
185
186    tvp->pos = p;
187    tvp->tag = tag;
188    tvp->val = val;
189
190    return 0;
191}
192
193/******************************************************************************\
194* Code for querying the current tag/value.
195\******************************************************************************/
196
197/* Get the current tag. */
198char *jas_tvparser_gettag(jas_tvparser_t *tvp)
199{
200    return tvp->tag;
201}
202
203/* Get the current value. */
204char *jas_tvparser_getval(jas_tvparser_t *tvp)
205{
206    return tvp->val;
207}
208
209/******************************************************************************\
210* Miscellaneous code.
211\******************************************************************************/
212
213/* Lookup a tag by name. */
214jas_taginfo_t *jas_taginfos_lookup(jas_taginfo_t *taginfos, const char *name)
215{
216    jas_taginfo_t *taginfo;
217    taginfo = taginfos;
218    while (taginfo->id >= 0) {
219        if (!strcmp(taginfo->name, name)) {
220            return taginfo;
221        }
222        ++taginfo;
223    }
224    return 0;
225}
226
227/* This function is simply for convenience. */
228/* One can avoid testing for the special case of a null pointer, by
229  using this function.   This function never returns a null pointer.  */
230jas_taginfo_t *jas_taginfo_nonull(jas_taginfo_t *taginfo)
231{
232    static jas_taginfo_t invalidtaginfo = {
233        -1, 0
234    };
235
236    return taginfo ? taginfo : &invalidtaginfo;
237}
238