1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
use bindings::*;
use c_helpers::*;
use libc;
use libc::{c_char, c_void, size_t};
use std::ffi::{CStr, CString};
use std::str;
use tree::{Document, DocumentRef, Node};
#[derive(Clone)]
pub struct Context {
pub context_ptr: xmlXPathContextPtr,
document: DocumentRef,
}
impl Drop for Context {
fn drop(&mut self) {
unsafe {
xmlXPathFreeContext(self.context_ptr);
}
}
}
#[derive(Clone)]
pub struct Object {
pub ptr: xmlXPathObjectPtr,
document: DocumentRef,
}
impl Context {
pub fn new(doc: &Document) -> Result<Context, ()> {
let ctxtptr = unsafe { xmlXPathNewContext(doc.doc_ptr()) };
if ctxtptr.is_null() {
Err(())
} else {
Ok(Context {
context_ptr: ctxtptr,
document: doc.0.clone(),
})
}
}
pub(crate) fn new_ptr(docref: DocumentRef) -> Result<Context, ()> {
let ctxtptr = unsafe { xmlXPathNewContext(docref.borrow().doc_ptr) };
if ctxtptr.is_null() {
Err(())
} else {
Ok(Context {
context_ptr: ctxtptr,
document: docref.clone(),
})
}
}
pub fn register_namespace(&self, prefix: &str, href: &str) -> Result<(), ()> {
let c_prefix = CString::new(prefix).unwrap();
let c_href = CString::new(href).unwrap();
unsafe {
let result = xmlXPathRegisterNs(
self.context_ptr,
c_prefix.as_bytes().as_ptr(),
c_href.as_bytes().as_ptr(),
);
if result != 0 {
Err(())
} else {
Ok(())
}
}
}
pub fn evaluate(&self, xpath: &str) -> Result<Object, ()> {
let c_xpath = CString::new(xpath).unwrap();
let ptr = unsafe { xmlXPathEvalExpression(c_xpath.as_bytes().as_ptr(), self.context_ptr) };
if ptr.is_null() {
Err(())
} else {
Ok(Object {
ptr,
document: self.document.clone(),
})
}
}
pub fn set_context_node(&mut self, node: &Node) -> Result<(), ()> {
unsafe {
let result = xmlXPathSetContextNode(node.node_ptr(), self.context_ptr);
if result != 0 {
return Err(());
}
}
Ok(())
}
pub fn findnodes(&mut self, xpath: &str, node_opt: Option<&Node>) -> Result<Vec<Node>, ()> {
if let Some(node) = node_opt {
self.set_context_node(node)?;
}
let evaluated = self.evaluate(xpath)?;
Ok(evaluated.get_nodes_as_vec())
}
pub fn findvalue(&mut self, xpath: &str, node_opt: Option<&Node>) -> Result<String, ()> {
if let Some(node) = node_opt {
self.set_context_node(node)?;
}
let evaluated = self.evaluate(xpath)?;
Ok(evaluated.to_string())
}
}
impl Drop for Object {
fn drop(&mut self) {
unsafe {
xmlXPathFreeObject(self.ptr);
}
}
}
impl Object {
pub fn get_number_of_nodes(&self) -> usize {
let v = xmlXPathObjectNumberOfNodes(self.ptr);
if v == -1 {
panic!("rust-libxml: xpath: Passed in null pointer!");
}
if v == -2 {
return 0;
}
if v < -2 {
panic!("rust-libxml: xpath: expected non-negative number of result nodes");
}
v as usize
}
pub fn get_nodes_as_vec(&self) -> Vec<Node> {
let n = self.get_number_of_nodes();
let mut vec: Vec<Node> = Vec::with_capacity(n);
for i in 0..n {
let ptr = xmlXPathObjectGetNode(self.ptr, i as size_t);
if ptr.is_null() {
panic!("rust-libxml: xpath: found null pointer result set");
}
let node = Node::wrap(ptr, self.document.clone());
vec.push(node);
}
vec
}
pub fn to_string(&self) -> String {
unsafe {
let receiver = xmlXPathCastToString(self.ptr);
let c_string = CStr::from_ptr(receiver as *const c_char);
let rust_string = str::from_utf8(c_string.to_bytes()).unwrap().to_owned();
libc::free(receiver as *mut c_void);
rust_string
}
}
}