summaryrefslogtreecommitdiff
path: root/Build/source/texk/dvisvgm/dvisvgm-1.2.2/src/InputReader.cpp
blob: 3899a2362b2ded8ff1562c9251a61b00e9321cb9 (plain)
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
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
/*************************************************************************
** InputReader.cpp                                                      **
**                                                                      **
** This file is part of dvisvgm -- the DVI to SVG converter             **
** Copyright (C) 2005-2013 Martin Gieseking <martin.gieseking@uos.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 <http://www.gnu.org/licenses/>. **
*************************************************************************/

#include <cmath>
#include <vector>
#include "InputReader.h"

using namespace std;


/** Skips n characters. */
void InputReader::skip (size_t n) {
	while (n-- > 0)
		get();
}


/** Moves the buffer pointer to the next non-space character. A following call
 *  of get() returns this character. */
void InputReader::skipSpace () {
	while (isspace(peek()))
		get();
}


/** Tries to find a given string and skips all characters preceding that string.
 *  @param[in] s string to look for (must not be longer than the maximal buffer size)
 *  @param[in] consume if true, the buffer pointer is moved to the first character following string s
 *  @return true if s was found */
bool InputReader::skipUntil (const char *s, bool consume) {
	bool found = false;
	while (!eof() && !(found = check(s, consume)))
		get();
	return found;
}


/** Looks for the first occurrence of a given character. 
 *  @param[in] c character to lookup 
 *  @return position of character relative to current location, -1 if character was not found */
int InputReader::find (char c) const {
	int pos = 0;
	int cc;
	while ((cc = peek(pos)) >= 0 && cc != c)
		pos++;
	return cc < 0 ? -1 : pos;
}


/** Checks if the next characters to be read match a given string.
 *  @param[in] s string to be matched
 *  @param[in] consume if true, the characters of the matched string are skipped
 *  @return true if s matches */
bool InputReader::check (const char *s, bool consume) {
	size_t count = 0;
	for (const char *p=s; *p; p++) {
		if (peek(count++) != *p)
			return false;
	}
	if (consume)
		skip(count);
	return true;
}


int InputReader::compare (const char *s, bool consume) {
	size_t count = 0;
	for (const char *p=s; *p; p++) {
		int c = peek(count++);
		if (c != *p)
			return *p < c ? -1 : 1;
	}
	if (consume)
		skip(count);
	return 0;
}


/** Reads an integer from the buffer. All characters that are part of
 *  the read integer constant are skipped. If this function returns false,
 *  the buffer pointer points to the same position as before the function call.
 *  @param[out] val contains the read integer value on success
 *  @param[in] accept_sign if false, only positive integers (without sign) are accepted
 *  @return true if integer could be read */
bool InputReader::parseInt (int &val, bool accept_sign) {
	val = 0;
	int fac=1;
	char sign;    // explicitly given sign
	if (accept_sign && ((sign = peek()) == '+' || sign == '-')) {
		if (isdigit(peek(1))) {
			get();  // skip sign
			if (sign == '-')
				fac = -1;
		}
		else
			return false;
	}
	else if (!isdigit(peek()))
		return false;

	while (isdigit(peek()))
		val = val*10 + (get()-'0');
	val *= fac;
	return true;
}


bool InputReader::parseUInt (unsigned &val) {
	val = 0;
	if (!isdigit(peek()))
		return false;
	while (isdigit(peek()))
		val = val*10 + (get()-'0');
	return true;
}


bool InputReader::parseInt (int base, int &val) {
	if (base < 2 || base > 32)
		return false;

	const char *digits = "0123456789abcdefghijklmnopqrstuvwxyz";
	const char maxdigit = digits[base-1];
	char c;
	if (!isalnum(c = tolower(peek())) || c > maxdigit)
		return false;

	val = 0;
	while (isalnum(c = tolower(peek())) && c <= maxdigit) {
		get();
		int digit = c - (c <= '9' ? '0' : 'a'-10);
		val = val*base + digit;
	}
	return true;
}


/** Reads a double from the buffer. All characters that are part of
 *  the read double constant are skipped. If this function returns false,
 *  the buffer pointer points to the same position as before the function call.
 *  @param[out] val contains the read double value on success
 *  @return number details: 0=no number, 'i'=integer, 'f'=floating point number */
char InputReader::parseDouble (double &val) {
	int fac=1;
	int int_part=0;
	bool is_float = false;
	skipSpace();
	char sign = peek();
	if (parseInt(int_part)) { // match [+-]?[0-9]+\.?
		if (peek() == '.') {
			get();
			is_float = true;
		}
		if (int_part < 0 || sign == '-') {
			fac = -1;
			int_part = -int_part;
		}
	}
	else {  // match [+-]?\.
		char sign;   // explicitly given sign
		if ((sign = peek()) == '+' || sign == '-') { // match [+-]?\.[0-9]
			if (peek(1) != '.' || !isdigit(peek(2)))
				return 0;
			if (sign == '-')
				fac = -1;
			skip(2);  // skip sign and dot
		}
		else if (peek() == '.' && isdigit(peek(1)))
			get();
		else
			return 0;
		is_float = true;
	}
	// parse fractional part
	double frac_part=0.0;
	for (double u=10; isdigit(peek()); u*=10)
		frac_part += (get()-'0')/u;
	val = (int_part + frac_part) * fac;
	// parse exponent
	char c;
	if (tolower(peek()) == 'e' && (isdigit(c=peek(1)) || ((c == '+' || c == '-') && isdigit(peek(2))))) {
		get(); // skip 'e'
		int exp;
		parseInt(exp);
		val *= pow(10.0, exp);
		is_float = true;
	}
	return is_float ? 'f' : 'i';
}


/** Reads an integer value from the buffer. If no valid integer constant
 *  could be found at the current position 0 is returned. */
int InputReader::getInt () {
	skipSpace();
	int val;
	return parseInt(val) ? val : 0;
}


/** Reads an double value from the buffer. If no valid double constant
 *  could be found at the current position 0 is returned. */
double InputReader::getDouble () {
	skipSpace();
	double val;
	return parseDouble(val) ? val : 0.0;
}


string InputReader::getWord () {
	string ret;
	skipSpace();
	while (isalpha(peek()))
		ret += get();
	return ret;
}


char InputReader::getPunct () {
	skipSpace();
	if (ispunct(peek()))
		return get();
	return 0;
}


/** Reads a string delimited by a given quotation character. 
 *  Before reading the string, all leading whitespace is skipped. Then, the function checks
 *  for the given quotation character. If it is found, all characters until the second
 *  appearance of the quotation char are appended to the result. Otherwise, an empty string
 *  is returned. If the quotation character is 0, the behavior of this function is identical to
 *  a call of getString(). 
 *  @param[in] quotechar the quotation character bounding the string to be read 
 *  @return the string read */
string InputReader::getQuotedString (char quotechar) {
	if (quotechar == 0)
		return getString();
	
	string ret;
	skipSpace();
	if (peek() == quotechar) {
		get();
		while (!eof() && peek() != quotechar)
			ret += get();
		get();
	}
	return ret;
}


/** Reads a string delimited by whitespace and/or invisible characters. 
 *  Before reading the string, all leading whitespace is skipped. Then, the function adds
 *  all printable characters to the result until a whitespace, an unprintable character, or
 *  EOF is found.
 *  @return the string read */
string InputReader::getString () {
	string ret;
	skipSpace();
	while (!eof() && !isspace(peek()) && isprint(peek()))
		ret += get();
	return ret;
}


/** Reads a given number of characters and returns the resulting string. 
 *  @param n number of character to read
 *  @return the string read */
string InputReader::getString (size_t n) {
	string ret;
	while (n-- > 0)
		ret += get();
	return ret;
}


/*string InputReader::getString (char quotechar) {
	string ret;
	skipSpace();
	if (quotechar == 0) {
		while (!eof() && !isspace(peek()) && isprint(peek()))
			ret += get();
	}
	else if (peek() == quotechar) {
		get();
		while (!eof() && peek() != quotechar)
			ret += get();
		get();
	}
	return ret;
}*/


int InputReader::parseAttributes (map<string,string> &attr) {
	bool ready=false;
	while (!eof() && !ready) {
		string key;
		skipSpace();
		while (isalnum(peek()))
			key += get();
		skipSpace();
		if (peek() == '=') {
			get();
			skipSpace();
			string val = getString();
			attr[key] = val;
		}
		else
			ready = true;
	}
	return attr.size();
}

//////////////////////////////////////////


int StreamInputReader::peek (size_t n) const {
	if (n == 0)
		return peek();
	vector<char> chars(n);
	_is.read(&chars[0], n);
	int ret = peek();
	for (int i=n-1; i >= 0; i--)
		_is.putback(chars[i]);
	return ret;
}