1 /*
2 Open Asset Import Library (assimp)
3 ----------------------------------------------------------------------
4 
5 Copyright (c) 2006-2017, assimp team
6 
7 All rights reserved.
8 
9 Redistribution and use of this software in source and binary forms,
10 with or without modification, are permitted provided that the
11 following conditions are met:
12 
13 * Redistributions of source code must retain the above
14   copyright notice, this list of conditions and the
15   following disclaimer.
16 
17 * Redistributions in binary form must reproduce the above
18   copyright notice, this list of conditions and the
19   following disclaimer in the documentation and/or other
20   materials provided with the distribution.
21 
22 * Neither the name of the assimp team, nor the names of its
23   contributors may be used to endorse or promote products
24   derived from this software without specific prior
25   written permission of the assimp team.
26 
27 THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
28 "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
29 LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
30 A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
31 OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
32 SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
33 LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
34 DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
35 THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
36 (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
37 OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
38 
39 ----------------------------------------------------------------------
40 */
41 
42 /** @file  LineSplitter.h
43  *  @brief LineSplitter, a helper class to iterate through all lines
44  *    of a file easily. Works with StreamReader.
45  */
46 #ifndef INCLUDED_LINE_SPLITTER_H
47 #define INCLUDED_LINE_SPLITTER_H
48 
49 #include <stdexcept>
50 
51 #include "StreamReader.h"
52 #include "ParsingUtils.h"
53 
54 namespace Assimp {
55 
56 // ------------------------------------------------------------------------------------------------
57 /** Usage:
58 @code
59 for(LineSplitter splitter(stream);splitter;++splitter) {
60 
61     if (*splitter == "hi!") {
62        ...
63     }
64     else if (splitter->substr(0,5) == "hello") {
65        ...
66        // access the third token in the line (tokens are space-separated)
67        if (strtol(splitter[2]) > 5) { .. }
68     }
69 
70     std::cout << "Current line is: " << splitter.get_index() << std::endl;
71 }
72 @endcode
73 */
74 // ------------------------------------------------------------------------------------------------
75 class LineSplitter {
76 public:
77     typedef size_t line_idx;
78 
79     // -----------------------------------------
80     /** construct from existing stream reader
81     note: trim is *always* assumed true if skyp_empty_lines==true
82     */
83     LineSplitter(StreamReaderLE& stream, bool skip_empty_lines = true, bool trim = true)
84     : idx( 0 )
85     , stream(stream)
86     , swallow()
87     , skip_empty_lines(skip_empty_lines)
88     , trim(trim) {
89         cur.reserve(1024);
90         operator++();
91 
92         idx = 0;
93     }
94 
~LineSplitter()95     ~LineSplitter() {
96         // empty
97     }
98 
99 public:
100 
101     // -----------------------------------------
102     /** pseudo-iterator increment */
103     LineSplitter& operator++() {
104         if(swallow) {
105             swallow = false;
106             return *this;
107         }
108         if (!*this) {
109             throw std::logic_error("End of file, no more lines to be retrieved.");
110         }
111         char s;
112         cur.clear();
113         while(stream.GetRemainingSize() && (s = stream.GetI1(),1)) {
114             if (s == '\n' || s == '\r') {
115                 if (skip_empty_lines) {
116                     while (stream.GetRemainingSize() && ((s = stream.GetI1()) == ' ' || s == '\r' || s == '\n'));
117                     if (stream.GetRemainingSize()) {
118                         stream.IncPtr(-1);
119                     }
120                 }
121                 else {
122                     // skip both potential line terminators but don't read past this line.
123                     if (stream.GetRemainingSize() && (s == '\r' && stream.GetI1() != '\n')) {
124                         stream.IncPtr(-1);
125                     }
126                     if (trim) {
127                         while (stream.GetRemainingSize() && ((s = stream.GetI1()) == ' ' || s == '\t'));
128                         if (stream.GetRemainingSize()) {
129                             stream.IncPtr(-1);
130                         }
131                     }
132                 }
133                 break;
134             }
135             cur += s;
136         }
137         ++idx;
138         return *this;
139     }
140 
141     // -----------------------------------------
142     LineSplitter& operator++(int) {
143         return ++(*this);
144     }
145 
146     // -----------------------------------------
147     /** get a pointer to the beginning of a particular token */
148     const char* operator[] (size_t idx) const {
149         const char* s = operator->()->c_str();
150 
151         SkipSpaces(&s);
152         for(size_t i = 0; i < idx; ++i) {
153 
154             for(;!IsSpace(*s); ++s) {
155                 if(IsLineEnd(*s)) {
156                     throw std::range_error("Token index out of range, EOL reached");
157                 }
158             }
159             SkipSpaces(&s);
160         }
161         return s;
162     }
163 
164     // -----------------------------------------
165     /** extract the start positions of N tokens from the current line*/
166     template <size_t N>
get_tokens(const char * (& tokens)[N])167     void get_tokens(const char* (&tokens)[N]) const {
168         const char* s = operator->()->c_str();
169 
170         SkipSpaces(&s);
171         for(size_t i = 0; i < N; ++i) {
172             if(IsLineEnd(*s)) {
173 
174                 throw std::range_error("Token count out of range, EOL reached");
175 
176             }
177             tokens[i] = s;
178 
179             for(;*s && !IsSpace(*s); ++s);
180             SkipSpaces(&s);
181         }
182     }
183 
184     // -----------------------------------------
185     /** member access */
186     const std::string* operator -> () const {
187         return &cur;
188     }
189 
190     std::string operator* () const {
191         return cur;
192     }
193 
194     // -----------------------------------------
195     /** boolean context */
196     operator bool() const {
197         return stream.GetRemainingSize()>0;
198     }
199 
200     // -----------------------------------------
201     /** line indices are zero-based, empty lines are included */
line_idx()202     operator line_idx() const {
203         return idx;
204     }
205 
get_index()206     line_idx get_index() const {
207         return idx;
208     }
209 
210     // -----------------------------------------
211     /** access the underlying stream object */
get_stream()212     StreamReaderLE& get_stream() {
213         return stream;
214     }
215 
216     // -----------------------------------------
217     /** !strcmp((*this)->substr(0,strlen(check)),check) */
match_start(const char * check)218     bool match_start(const char* check) {
219         const size_t len = strlen(check);
220 
221         return len <= cur.length() && std::equal(check,check+len,cur.begin());
222     }
223 
224 
225     // -----------------------------------------
226     /** swallow the next call to ++, return the previous value. */
swallow_next_increment()227     void swallow_next_increment() {
228         swallow = true;
229     }
230 
231 private:
232     LineSplitter( const LineSplitter & );
233     LineSplitter &operator = ( const LineSplitter & );
234 
235 private:
236     line_idx idx;
237     std::string cur;
238     StreamReaderLE& stream;
239     bool swallow, skip_empty_lines, trim;
240 };
241 
242 }
243 #endif // INCLUDED_LINE_SPLITTER_H
244