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1
/*
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 * Copyright (c) 2002-2006 Michael Niedermayer <michaelni@gmx.at>
3
 * Copyright (c) 2006 Oded Shimon <ods15@ods15.dyndns.org>
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 *
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 * This file is part of Libav.
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 *
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 * Libav is free software; you can redistribute it and/or
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 * modify it under the terms of the GNU Lesser General Public
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 * License as published by the Free Software Foundation; either
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 * version 2.1 of the License, or (at your option) any later version.
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 *
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 * Libav is distributed in the hope that it will be useful,
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 * but WITHOUT ANY WARRANTY; without even the implied warranty of
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 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
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 * Lesser General Public License for more details.
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 *
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 * You should have received a copy of the GNU Lesser General Public
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 * License along with Libav; if not, write to the Free Software
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 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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 */
21

    
22
/**
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 * @file
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 * simple arithmetic expression evaluator.
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 *
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 * see http://joe.hotchkiss.com/programming/eval/eval.html
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 */
28

    
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#include "libavutil/avutil.h"
30
#include "eval.h"
31

    
32
typedef struct Parser {
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    const AVClass *class;
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    int stack_index;
35
    char *s;
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    const double *const_values;
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    const char * const *const_names;          // NULL terminated
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    double (* const *funcs1)(void *, double a);           // NULL terminated
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    const char * const *func1_names;          // NULL terminated
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    double (* const *funcs2)(void *, double a, double b); // NULL terminated
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    const char * const *func2_names;          // NULL terminated
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    void *opaque;
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    int log_offset;
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    void *log_ctx;
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#define VARS 10
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    double var[VARS];
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} Parser;
48

    
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static const AVClass class = { "Eval", av_default_item_name, NULL, LIBAVUTIL_VERSION_INT, offsetof(Parser,log_offset), offsetof(Parser,log_ctx) };
50

    
51
static const int8_t si_prefixes['z' - 'E' + 1] = {
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    ['y'-'E']= -24,
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    ['z'-'E']= -21,
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    ['a'-'E']= -18,
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    ['f'-'E']= -15,
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    ['p'-'E']= -12,
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    ['n'-'E']= - 9,
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    ['u'-'E']= - 6,
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    ['m'-'E']= - 3,
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    ['c'-'E']= - 2,
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    ['d'-'E']= - 1,
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    ['h'-'E']=   2,
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    ['k'-'E']=   3,
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    ['K'-'E']=   3,
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    ['M'-'E']=   6,
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    ['G'-'E']=   9,
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    ['T'-'E']=  12,
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    ['P'-'E']=  15,
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    ['E'-'E']=  18,
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    ['Z'-'E']=  21,
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    ['Y'-'E']=  24,
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};
73

    
74
double av_strtod(const char *numstr, char **tail)
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{
76
    double d;
77
    char *next;
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    d = strtod(numstr, &next);
79
    /* if parsing succeeded, check for and interpret postfixes */
80
    if (next!=numstr) {
81
        if (*next >= 'E' && *next <= 'z') {
82
            int e= si_prefixes[*next - 'E'];
83
            if (e) {
84
                if (next[1] == 'i') {
85
                    d*= pow( 2, e/0.3);
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                    next+=2;
87
                } else {
88
                    d*= pow(10, e);
89
                    next++;
90
                }
91
            }
92
        }
93

    
94
        if (*next=='B') {
95
            d*=8;
96
            next++;
97
        }
98
    }
99
    /* if requested, fill in tail with the position after the last parsed
100
       character */
101
    if (tail)
102
        *tail = next;
103
    return d;
104
}
105

    
106
#define IS_IDENTIFIER_CHAR(c) ((c) - '0' <= 9U || (c) - 'a' <= 25U || (c) - 'A' <= 25U || (c) == '_')
107

    
108
static int strmatch(const char *s, const char *prefix)
109
{
110
    int i;
111
    for (i=0; prefix[i]; i++) {
112
        if (prefix[i] != s[i]) return 0;
113
    }
114
    /* return 1 only if the s identifier is terminated */
115
    return !IS_IDENTIFIER_CHAR(s[i]);
116
}
117

    
118
struct AVExpr {
119
    enum {
120
        e_value, e_const, e_func0, e_func1, e_func2,
121
        e_squish, e_gauss, e_ld, e_isnan,
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        e_mod, e_max, e_min, e_eq, e_gt, e_gte,
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        e_pow, e_mul, e_div, e_add,
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        e_last, e_st, e_while, e_floor, e_ceil, e_trunc,
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    } type;
126
    double value; // is sign in other types
127
    union {
128
        int const_index;
129
        double (*func0)(double);
130
        double (*func1)(void *, double);
131
        double (*func2)(void *, double, double);
132
    } a;
133
    struct AVExpr *param[2];
134
};
135

    
136
static double eval_expr(Parser *p, AVExpr *e)
137
{
138
    switch (e->type) {
139
        case e_value:  return e->value;
140
        case e_const:  return e->value * p->const_values[e->a.const_index];
141
        case e_func0:  return e->value * e->a.func0(eval_expr(p, e->param[0]));
142
        case e_func1:  return e->value * e->a.func1(p->opaque, eval_expr(p, e->param[0]));
143
        case e_func2:  return e->value * e->a.func2(p->opaque, eval_expr(p, e->param[0]), eval_expr(p, e->param[1]));
144
        case e_squish: return 1/(1+exp(4*eval_expr(p, e->param[0])));
145
        case e_gauss: { double d = eval_expr(p, e->param[0]); return exp(-d*d/2)/sqrt(2*M_PI); }
146
        case e_ld:     return e->value * p->var[av_clip(eval_expr(p, e->param[0]), 0, VARS-1)];
147
        case e_isnan:  return e->value * !!isnan(eval_expr(p, e->param[0]));
148
        case e_floor:  return e->value * floor(eval_expr(p, e->param[0]));
149
        case e_ceil :  return e->value * ceil (eval_expr(p, e->param[0]));
150
        case e_trunc:  return e->value * trunc(eval_expr(p, e->param[0]));
151
        case e_while: {
152
            double d = NAN;
153
            while (eval_expr(p, e->param[0]))
154
                d=eval_expr(p, e->param[1]);
155
            return d;
156
        }
157
        default: {
158
            double d = eval_expr(p, e->param[0]);
159
            double d2 = eval_expr(p, e->param[1]);
160
            switch (e->type) {
161
                case e_mod: return e->value * (d - floor(d/d2)*d2);
162
                case e_max: return e->value * (d >  d2 ?   d : d2);
163
                case e_min: return e->value * (d <  d2 ?   d : d2);
164
                case e_eq:  return e->value * (d == d2 ? 1.0 : 0.0);
165
                case e_gt:  return e->value * (d >  d2 ? 1.0 : 0.0);
166
                case e_gte: return e->value * (d >= d2 ? 1.0 : 0.0);
167
                case e_pow: return e->value * pow(d, d2);
168
                case e_mul: return e->value * (d * d2);
169
                case e_div: return e->value * (d / d2);
170
                case e_add: return e->value * (d + d2);
171
                case e_last:return e->value * d2;
172
                case e_st : return e->value * (p->var[av_clip(d, 0, VARS-1)]= d2);
173
            }
174
        }
175
    }
176
    return NAN;
177
}
178

    
179
static int parse_expr(AVExpr **e, Parser *p);
180

    
181
void av_expr_free(AVExpr *e)
182
{
183
    if (!e) return;
184
    av_expr_free(e->param[0]);
185
    av_expr_free(e->param[1]);
186
    av_freep(&e);
187
}
188

    
189
static int parse_primary(AVExpr **e, Parser *p)
190
{
191
    AVExpr *d = av_mallocz(sizeof(AVExpr));
192
    char *next = p->s, *s0 = p->s;
193
    int ret, i;
194

    
195
    if (!d)
196
        return AVERROR(ENOMEM);
197

    
198
    /* number */
199
    d->value = av_strtod(p->s, &next);
200
    if (next != p->s) {
201
        d->type = e_value;
202
        p->s= next;
203
        *e = d;
204
        return 0;
205
    }
206
    d->value = 1;
207

    
208
    /* named constants */
209
    for (i=0; p->const_names && p->const_names[i]; i++) {
210
        if (strmatch(p->s, p->const_names[i])) {
211
            p->s+= strlen(p->const_names[i]);
212
            d->type = e_const;
213
            d->a.const_index = i;
214
            *e = d;
215
            return 0;
216
        }
217
    }
218

    
219
    p->s= strchr(p->s, '(');
220
    if (p->s==NULL) {
221
        av_log(p, AV_LOG_ERROR, "Undefined constant or missing '(' in '%s'\n", s0);
222
        p->s= next;
223
        av_expr_free(d);
224
        return AVERROR(EINVAL);
225
    }
226
    p->s++; // "("
227
    if (*next == '(') { // special case do-nothing
228
        av_freep(&d);
229
        if ((ret = parse_expr(&d, p)) < 0)
230
            return ret;
231
        if (p->s[0] != ')') {
232
            av_log(p, AV_LOG_ERROR, "Missing ')' in '%s'\n", s0);
233
            av_expr_free(d);
234
            return AVERROR(EINVAL);
235
        }
236
        p->s++; // ")"
237
        *e = d;
238
        return 0;
239
    }
240
    if ((ret = parse_expr(&(d->param[0]), p)) < 0) {
241
        av_expr_free(d);
242
        return ret;
243
    }
244
    if (p->s[0]== ',') {
245
        p->s++; // ","
246
        parse_expr(&d->param[1], p);
247
    }
248
    if (p->s[0] != ')') {
249
        av_log(p, AV_LOG_ERROR, "Missing ')' or too many args in '%s'\n", s0);
250
        av_expr_free(d);
251
        return AVERROR(EINVAL);
252
    }
253
    p->s++; // ")"
254

    
255
    d->type = e_func0;
256
         if (strmatch(next, "sinh"  )) d->a.func0 = sinh;
257
    else if (strmatch(next, "cosh"  )) d->a.func0 = cosh;
258
    else if (strmatch(next, "tanh"  )) d->a.func0 = tanh;
259
    else if (strmatch(next, "sin"   )) d->a.func0 = sin;
260
    else if (strmatch(next, "cos"   )) d->a.func0 = cos;
261
    else if (strmatch(next, "tan"   )) d->a.func0 = tan;
262
    else if (strmatch(next, "atan"  )) d->a.func0 = atan;
263
    else if (strmatch(next, "asin"  )) d->a.func0 = asin;
264
    else if (strmatch(next, "acos"  )) d->a.func0 = acos;
265
    else if (strmatch(next, "exp"   )) d->a.func0 = exp;
266
    else if (strmatch(next, "log"   )) d->a.func0 = log;
267
    else if (strmatch(next, "abs"   )) d->a.func0 = fabs;
268
    else if (strmatch(next, "squish")) d->type = e_squish;
269
    else if (strmatch(next, "gauss" )) d->type = e_gauss;
270
    else if (strmatch(next, "mod"   )) d->type = e_mod;
271
    else if (strmatch(next, "max"   )) d->type = e_max;
272
    else if (strmatch(next, "min"   )) d->type = e_min;
273
    else if (strmatch(next, "eq"    )) d->type = e_eq;
274
    else if (strmatch(next, "gte"   )) d->type = e_gte;
275
    else if (strmatch(next, "gt"    )) d->type = e_gt;
276
    else if (strmatch(next, "lte"   )) { AVExpr *tmp = d->param[1]; d->param[1] = d->param[0]; d->param[0] = tmp; d->type = e_gt; }
277
    else if (strmatch(next, "lt"    )) { AVExpr *tmp = d->param[1]; d->param[1] = d->param[0]; d->param[0] = tmp; d->type = e_gte; }
278
    else if (strmatch(next, "ld"    )) d->type = e_ld;
279
    else if (strmatch(next, "isnan" )) d->type = e_isnan;
280
    else if (strmatch(next, "st"    )) d->type = e_st;
281
    else if (strmatch(next, "while" )) d->type = e_while;
282
    else if (strmatch(next, "floor" )) d->type = e_floor;
283
    else if (strmatch(next, "ceil"  )) d->type = e_ceil;
284
    else if (strmatch(next, "trunc" )) d->type = e_trunc;
285
    else {
286
        for (i=0; p->func1_names && p->func1_names[i]; i++) {
287
            if (strmatch(next, p->func1_names[i])) {
288
                d->a.func1 = p->funcs1[i];
289
                d->type = e_func1;
290
                *e = d;
291
                return 0;
292
            }
293
        }
294

    
295
        for (i=0; p->func2_names && p->func2_names[i]; i++) {
296
            if (strmatch(next, p->func2_names[i])) {
297
                d->a.func2 = p->funcs2[i];
298
                d->type = e_func2;
299
                *e = d;
300
                return 0;
301
            }
302
        }
303

    
304
        av_log(p, AV_LOG_ERROR, "Unknown function in '%s'\n", s0);
305
        av_expr_free(d);
306
        return AVERROR(EINVAL);
307
    }
308

    
309
    *e = d;
310
    return 0;
311
}
312

    
313
static AVExpr *new_eval_expr(int type, int value, AVExpr *p0, AVExpr *p1)
314
{
315
    AVExpr *e = av_mallocz(sizeof(AVExpr));
316
    if (!e)
317
        return NULL;
318
    e->type     =type   ;
319
    e->value    =value  ;
320
    e->param[0] =p0     ;
321
    e->param[1] =p1     ;
322
    return e;
323
}
324

    
325
static int parse_pow(AVExpr **e, Parser *p, int *sign)
326
{
327
    *sign= (*p->s == '+') - (*p->s == '-');
328
    p->s += *sign&1;
329
    return parse_primary(e, p);
330
}
331

    
332
static int parse_factor(AVExpr **e, Parser *p)
333
{
334
    int sign, sign2, ret;
335
    AVExpr *e0, *e1, *e2;
336
    if ((ret = parse_pow(&e0, p, &sign)) < 0)
337
        return ret;
338
    while(p->s[0]=='^'){
339
        e1 = e0;
340
        p->s++;
341
        if ((ret = parse_pow(&e2, p, &sign2)) < 0) {
342
            av_expr_free(e1);
343
            return ret;
344
        }
345
        e0 = new_eval_expr(e_pow, 1, e1, e2);
346
        if (!e0) {
347
            av_expr_free(e1);
348
            av_expr_free(e2);
349
            return AVERROR(ENOMEM);
350
        }
351
        if (e0->param[1]) e0->param[1]->value *= (sign2|1);
352
    }
353
    if (e0) e0->value *= (sign|1);
354

    
355
    *e = e0;
356
    return 0;
357
}
358

    
359
static int parse_term(AVExpr **e, Parser *p)
360
{
361
    int ret;
362
    AVExpr *e0, *e1, *e2;
363
    if ((ret = parse_factor(&e0, p)) < 0)
364
        return ret;
365
    while (p->s[0]=='*' || p->s[0]=='/') {
366
        int c= *p->s++;
367
        e1 = e0;
368
        if ((ret = parse_factor(&e2, p)) < 0) {
369
            av_expr_free(e1);
370
            return ret;
371
        }
372
        e0 = new_eval_expr(c == '*' ? e_mul : e_div, 1, e1, e2);
373
        if (!e0) {
374
            av_expr_free(e1);
375
            av_expr_free(e2);
376
            return AVERROR(ENOMEM);
377
        }
378
    }
379
    *e = e0;
380
    return 0;
381
}
382

    
383
static int parse_subexpr(AVExpr **e, Parser *p)
384
{
385
    int ret;
386
    AVExpr *e0, *e1, *e2;
387
    if ((ret = parse_term(&e0, p)) < 0)
388
        return ret;
389
    while (*p->s == '+' || *p->s == '-') {
390
        e1 = e0;
391
        if ((ret = parse_term(&e2, p)) < 0) {
392
            av_expr_free(e1);
393
            return ret;
394
        }
395
        e0 = new_eval_expr(e_add, 1, e1, e2);
396
        if (!e0) {
397
            av_expr_free(e1);
398
            av_expr_free(e2);
399
            return AVERROR(ENOMEM);
400
        }
401
    };
402

    
403
    *e = e0;
404
    return 0;
405
}
406

    
407
static int parse_expr(AVExpr **e, Parser *p)
408
{
409
    int ret;
410
    AVExpr *e0, *e1, *e2;
411
    if (p->stack_index <= 0) //protect against stack overflows
412
        return AVERROR(EINVAL);
413
    p->stack_index--;
414

    
415
    if ((ret = parse_subexpr(&e0, p)) < 0)
416
        return ret;
417
    while (*p->s == ';') {
418
        p->s++;
419
        e1 = e0;
420
        if ((ret = parse_subexpr(&e2, p)) < 0) {
421
            av_expr_free(e1);
422
            return ret;
423
        }
424
        e0 = new_eval_expr(e_last, 1, e1, e2);
425
        if (!e0) {
426
            av_expr_free(e1);
427
            av_expr_free(e2);
428
            return AVERROR(ENOMEM);
429
        }
430
    };
431

    
432
    p->stack_index++;
433
    *e = e0;
434
    return 0;
435
}
436

    
437
static int verify_expr(AVExpr *e)
438
{
439
    if (!e) return 0;
440
    switch (e->type) {
441
        case e_value:
442
        case e_const: return 1;
443
        case e_func0:
444
        case e_func1:
445
        case e_squish:
446
        case e_ld:
447
        case e_gauss:
448
        case e_isnan:
449
        case e_floor:
450
        case e_ceil:
451
        case e_trunc:
452
            return verify_expr(e->param[0]);
453
        default: return verify_expr(e->param[0]) && verify_expr(e->param[1]);
454
    }
455
}
456

    
457
int av_expr_parse(AVExpr **expr, const char *s,
458
                  const char * const *const_names,
459
                  const char * const *func1_names, double (* const *funcs1)(void *, double),
460
                  const char * const *func2_names, double (* const *funcs2)(void *, double, double),
461
                  int log_offset, void *log_ctx)
462
{
463
    Parser p;
464
    AVExpr *e = NULL;
465
    char *w = av_malloc(strlen(s) + 1);
466
    char *wp = w;
467
    const char *s0 = s;
468
    int ret = 0;
469

    
470
    if (!w)
471
        return AVERROR(ENOMEM);
472

    
473
    while (*s)
474
        if (!isspace(*s++)) *wp++ = s[-1];
475
    *wp++ = 0;
476

    
477
    p.class      = &class;
478
    p.stack_index=100;
479
    p.s= w;
480
    p.const_names = const_names;
481
    p.funcs1      = funcs1;
482
    p.func1_names = func1_names;
483
    p.funcs2      = funcs2;
484
    p.func2_names = func2_names;
485
    p.log_offset = log_offset;
486
    p.log_ctx    = log_ctx;
487

    
488
    if ((ret = parse_expr(&e, &p)) < 0)
489
        goto end;
490
    if (*p.s) {
491
        av_log(&p, AV_LOG_ERROR, "Invalid chars '%s' at the end of expression '%s'\n", p.s, s0);
492
        ret = AVERROR(EINVAL);
493
        goto end;
494
    }
495
    if (!verify_expr(e)) {
496
        av_expr_free(e);
497
        ret = AVERROR(EINVAL);
498
        goto end;
499
    }
500
    *expr = e;
501
end:
502
    av_free(w);
503
    return ret;
504
}
505

    
506
double av_expr_eval(AVExpr *e, const double *const_values, void *opaque)
507
{
508
    Parser p;
509

    
510
    p.const_values = const_values;
511
    p.opaque     = opaque;
512
    return eval_expr(&p, e);
513
}
514

    
515
int av_expr_parse_and_eval(double *d, const char *s,
516
                           const char * const *const_names, const double *const_values,
517
                           const char * const *func1_names, double (* const *funcs1)(void *, double),
518
                           const char * const *func2_names, double (* const *funcs2)(void *, double, double),
519
                           void *opaque, int log_offset, void *log_ctx)
520
{
521
    AVExpr *e = NULL;
522
    int ret = av_expr_parse(&e, s, const_names, func1_names, funcs1, func2_names, funcs2, log_offset, log_ctx);
523

    
524
    if (ret < 0) {
525
        *d = NAN;
526
        return ret;
527
    }
528
    *d = av_expr_eval(e, const_values, opaque);
529
    av_expr_free(e);
530
    return isnan(*d) ? AVERROR(EINVAL) : 0;
531
}
532

    
533
#if FF_API_OLD_EVAL_NAMES
534
int av_parse_expr(AVExpr **expr, const char *s,
535
                  const char * const *const_names,
536
                  const char * const *func1_names, double (* const *funcs1)(void *, double),
537
                  const char * const *func2_names, double (* const *funcs2)(void *, double, double),
538
                  int log_offset, void *log_ctx)
539
{
540
    return av_expr_parse(expr, s, const_names, func1_names, funcs1, func2_names, funcs2,
541
                      log_offset, log_ctx);
542
}
543

    
544
double av_eval_expr(AVExpr *e, const double *const_values, void *opaque)
545
{
546
    return av_expr_eval(e, const_values, opaque);
547
}
548

    
549
int av_parse_and_eval_expr(double *res, const char *s,
550
                           const char * const *const_names, const double *const_values,
551
                           const char * const *func1_names, double (* const *funcs1)(void *, double),
552
                           const char * const *func2_names, double (* const *funcs2)(void *, double, double),
553
                           void *opaque, int log_offset, void *log_ctx)
554
{
555
    return av_expr_parse_and_eval(res, s, const_names, const_values, func1_names, funcs1, func2_names, funcs2,
556
                                  opaque, log_offset, log_ctx);
557
}
558

    
559
void av_free_expr(AVExpr *e)
560
{
561
    av_expr_free(e);
562
}
563
#endif /* FF_API_OLD_EVAL_NAMES */
564

    
565
#ifdef TEST
566
#undef printf
567
static double const_values[] = {
568
    M_PI,
569
    M_E,
570
    0
571
};
572

    
573
static const char *const_names[] = {
574
    "PI",
575
    "E",
576
    0
577
};
578

    
579
int main(void)
580
{
581
    int i;
582
    double d;
583
    const char **expr, *exprs[] = {
584
        "",
585
        "1;2",
586
        "-20",
587
        "-PI",
588
        "+PI",
589
        "1+(5-2)^(3-1)+1/2+sin(PI)-max(-2.2,-3.1)",
590
        "80G/80Gi"
591
        "1k",
592
        "1Gi",
593
        "1gi",
594
        "1GiFoo",
595
        "1k+1k",
596
        "1Gi*3foo",
597
        "foo",
598
        "foo(",
599
        "foo()",
600
        "foo)",
601
        "sin",
602
        "sin(",
603
        "sin()",
604
        "sin)",
605
        "sin 10",
606
        "sin(1,2,3)",
607
        "sin(1 )",
608
        "1",
609
        "1foo",
610
        "bar + PI + E + 100f*2 + foo",
611
        "13k + 12f - foo(1, 2)",
612
        "1gi",
613
        "1Gi",
614
        "st(0, 123)",
615
        "st(1, 123); ld(1)",
616
        /* compute 1+2+...+N */
617
        "st(0, 1); while(lte(ld(0), 100), st(1, ld(1)+ld(0));st(0, ld(0)+1)); ld(1)",
618
        /* compute Fib(N) */
619
        "st(1, 1); st(2, 2); st(0, 1); while(lte(ld(0),10), st(3, ld(1)+ld(2)); st(1, ld(2)); st(2, ld(3)); st(0, ld(0)+1)); ld(3)",
620
        "while(0, 10)",
621
        "st(0, 1); while(lte(ld(0),100), st(1, ld(1)+ld(0)); st(0, ld(0)+1))",
622
        "isnan(1)",
623
        "isnan(NAN)",
624
        "floor(NAN)",
625
        "floor(123.123)",
626
        "floor(-123.123)",
627
        "trunc(123.123)",
628
        "trunc(-123.123)",
629
        "ceil(123.123)",
630
        "ceil(-123.123)",
631
        NULL
632
    };
633

    
634
    for (expr = exprs; *expr; expr++) {
635
        printf("Evaluating '%s'\n", *expr);
636
        av_expr_parse_and_eval(&d, *expr,
637
                               const_names, const_values,
638
                               NULL, NULL, NULL, NULL, NULL, 0, NULL);
639
        printf("'%s' -> %f\n\n", *expr, d);
640
    }
641

    
642
    av_expr_parse_and_eval(&d, "1+(5-2)^(3-1)+1/2+sin(PI)-max(-2.2,-3.1)",
643
                           const_names, const_values,
644
                           NULL, NULL, NULL, NULL, NULL, 0, NULL);
645
    printf("%f == 12.7\n", d);
646
    av_expr_parse_and_eval(&d, "80G/80Gi",
647
                           const_names, const_values,
648
                           NULL, NULL, NULL, NULL, NULL, 0, NULL);
649
    printf("%f == 0.931322575\n", d);
650

    
651
    for (i=0; i<1050; i++) {
652
        START_TIMER
653
            av_expr_parse_and_eval(&d, "1+(5-2)^(3-1)+1/2+sin(PI)-max(-2.2,-3.1)",
654
                                   const_names, const_values,
655
                                   NULL, NULL, NULL, NULL, NULL, 0, NULL);
656
        STOP_TIMER("av_expr_parse_and_eval")
657
    }
658
    return 0;
659
}
660
#endif