xref: /reactos/dll/win32/hhctrl.ocx/stream.c (revision cc439606)
1 /*
2  * Copyright 2007 Jacek Caban for CodeWeavers
3  *
4  * This library is free software; you can redistribute it and/or
5  * modify it under the terms of the GNU Lesser General Public
6  * License as published by the Free Software Foundation; either
7  * version 2.1 of the License, or (at your option) any later version.
8  *
9  * This library is distributed in the hope that it will be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
12  * Lesser General Public License for more details.
13  *
14  * You should have received a copy of the GNU Lesser General Public
15  * License along with this library; if not, write to the Free Software
16  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
17  */
18 
19 #include "hhctrl.h"
20 #include "stream.h"
21 
22 #include "wine/debug.h"
23 
24 WINE_DEFAULT_DEBUG_CHANNEL(htmlhelp);
25 
26 void strbuf_init(strbuf_t *buf)
27 {
28     buf->size = 8;
29     buf->len = 0;
30     buf->buf = heap_alloc(buf->size);
31 }
32 
33 void strbuf_zero(strbuf_t *buf)
34 {
35     buf->len = 0;
36 }
37 
38 void strbuf_free(strbuf_t *buf)
39 {
40     heap_free(buf->buf);
41 }
42 
43 static void strbuf_append(strbuf_t *buf, const char *data, int len)
44 {
45     if(buf->len+len > buf->size) {
46         buf->size = buf->len+len;
47         buf->buf = heap_realloc(buf->buf, buf->size);
48     }
49 
50     memcpy(buf->buf+buf->len, data, len);
51     buf->len += len;
52 }
53 
54 void stream_init(stream_t *stream, IStream *str)
55 {
56     memset(stream, 0, sizeof(stream_t));
57     stream->str = str;
58 }
59 
60 static BOOL stream_chr(stream_t *stream, strbuf_t *buf, char c)
61 {
62     BOOL b = TRUE;
63     ULONG i;
64 
65     while(b) {
66         for(i=stream->p; i<stream->size; i++) {
67             if(stream->buf[i] == c) {
68                 b = FALSE;
69                 break;
70             }
71         }
72 
73         if(buf && i > stream->p)
74             strbuf_append(buf, stream->buf+stream->p, i-stream->p);
75         stream->p = i;
76 
77         if(stream->p == stream->size) {
78             stream->p = 0;
79             IStream_Read(stream->str, stream->buf, sizeof(stream->buf), &stream->size);
80             if(!stream->size)
81                 break;
82         }
83     }
84 
85     return stream->size != 0;
86 }
87 
88 void get_node_name(strbuf_t *node, strbuf_t *name)
89 {
90     const char *ptr = node->buf+1;
91 
92     strbuf_zero(name);
93 
94     while(*ptr != '>' && !isspace(*ptr))
95         ptr++;
96 
97     strbuf_append(name, node->buf+1, ptr-node->buf-1);
98     strbuf_append(name, "", 1);
99 }
100 
101 /* Return the stream content up to the next HTML tag.
102  *
103  * Note: the first returned character is the end of the last tag (>).
104  */
105 BOOL next_content(stream_t *stream, strbuf_t *buf)
106 {
107     if(!stream_chr(stream, buf, '<'))
108         return FALSE;
109 
110     return TRUE;
111 }
112 
113 static BOOL find_node_end(stream_t *stream, strbuf_t *buf)
114 {
115     int tag_count = 0, b = buf->len;
116     char *p;
117 
118     while(1)
119     {
120         if(!stream_chr(stream, buf, '>'))
121             return FALSE;
122         if(buf->len == 0)
123             break;
124         p = &buf->buf[b];
125         while((p = memchr(p+1, '"', buf->len-(p+1-buf->buf))) != NULL)
126             tag_count++;
127         b = buf->len;
128         if(tag_count % 2 != 0)
129         {
130             if(!stream_chr(stream, buf, '"'))
131                 return FALSE;
132             tag_count++;
133         }
134         else
135             break;
136     }
137     return TRUE;
138 }
139 
140 BOOL next_node(stream_t *stream, strbuf_t *buf)
141 {
142     /* find the beginning of the next node */
143     if(!stream_chr(stream, NULL, '<'))
144         return FALSE;
145 
146     /* read out the data of the next node */
147     if(!find_node_end(stream, buf))
148         return FALSE;
149 
150     strbuf_append(buf, ">", 2);
151 
152     return TRUE;
153 }
154 
155 /*
156  * Find the value of a named HTML attribute.
157  *
158  * Note: Attribute names are case insensitive, so it is necessary to
159  * put both the node text and the attribute name in the same case
160  * before attempting a string search.
161  */
162 const char *get_attr(const char *node, const char *name, int *len)
163 {
164     const char *ptr, *ptr2;
165     int name_len, node_len;
166     char name_buf[32];
167     char *node_buf;
168     int i;
169 
170     /* Create a lower case copy of the node */
171     node_len = strlen(node)+1;
172     node_buf = heap_alloc(node_len*sizeof(char));
173     if(!node_buf)
174         return NULL;
175     memcpy(node_buf, node, node_len);
176     for(i=0;i<node_len;i++)
177         node_buf[i] = tolower(node_buf[i]);
178     /* Create a lower case copy of the attribute name (search string) */
179     name_len = strlen(name);
180     memcpy(name_buf, name, name_len);
181     for(i=0;i<name_len;i++)
182         name_buf[i] = tolower(name_buf[i]);
183     name_buf[name_len++] = '=';
184     name_buf[name_len++] = '\"';
185     name_buf[name_len] = 0;
186 
187     ptr = strstr(node_buf, name_buf);
188     if(!ptr) {
189         WARN("name not found\n");
190         heap_free(node_buf);
191         return NULL;
192     }
193 
194     ptr += name_len;
195     ptr2 = strchr(ptr, '\"');
196     if(!ptr2)
197     {
198         heap_free(node_buf);
199         return NULL;
200     }
201 
202     *len = ptr2-ptr;
203     /* Return the pointer offset within the original string */
204     ptr = node+(ptr-node_buf);
205 
206     heap_free(node_buf);
207     return ptr;
208 }
209