FFmpeg: libavutil/eval.c Source File

00001 /*
00002  * Copyright (c) 2002-2006 Michael Niedermayer <michaelni@gmx.at>
00003  * Copyright (c) 2006 Oded Shimon <ods15@ods15.dyndns.org>
00004  *
00005  * This file is part of FFmpeg.
00006  *
00007  * FFmpeg is free software; you can redistribute it and/or
00008  * modify it under the terms of the GNU Lesser General Public
00009  * License as published by the Free Software Foundation; either
00010  * version 2.1 of the License, or (at your option) any later version.
00011  *
00012  * FFmpeg is distributed in the hope that it will be useful,
00013  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00014  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00015  * Lesser General Public License for more details.
00016  *
00017  * You should have received a copy of the GNU Lesser General Public
00018  * License along with FFmpeg; if not, write to the Free Software
00019  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
00020  */
00021 
00029 #include <float.h>
00030 #include "avutil.h"
00031 #include "common.h"
00032 #include "eval.h"
00033 #include "log.h"
00034 #include "mathematics.h"
00035 
00036 typedef struct Parser {
00037     const AVClass *class;
00038     int stack_index;
00039     char *s;
00040     const double *const_values;
00041     const char * const *const_names;          // NULL terminated
00042     double (* const *funcs1)(void *, double a);           // NULL terminated
00043     const char * const *func1_names;          // NULL terminated
00044     double (* const *funcs2)(void *, double a, double b); // NULL terminated
00045     const char * const *func2_names;          // NULL terminated
00046     void *opaque;
00047     int log_offset;
00048     void *log_ctx;
00049 #define VARS 10
00050     double *var;
00051 } Parser;
00052 
00053 static const AVClass class = { "Eval", av_default_item_name, NULL, LIBAVUTIL_VERSION_INT, offsetof(Parser,log_offset), offsetof(Parser,log_ctx) };
00054 
00055 static const int8_t si_prefixes['z' - 'E' + 1] = {
00056     ['y'-'E']= -24,
00057     ['z'-'E']= -21,
00058     ['a'-'E']= -18,
00059     ['f'-'E']= -15,
00060     ['p'-'E']= -12,
00061     ['n'-'E']= - 9,
00062     ['u'-'E']= - 6,
00063     ['m'-'E']= - 3,
00064     ['c'-'E']= - 2,
00065     ['d'-'E']= - 1,
00066     ['h'-'E']=   2,
00067     ['k'-'E']=   3,
00068     ['K'-'E']=   3,
00069     ['M'-'E']=   6,
00070     ['G'-'E']=   9,
00071     ['T'-'E']=  12,
00072     ['P'-'E']=  15,
00073     ['E'-'E']=  18,
00074     ['Z'-'E']=  21,
00075     ['Y'-'E']=  24,
00076 };
00077 
00078 static const struct {
00079     const char *name;
00080     double value;
00081 } constants[] = {
00082     { "E",   M_E   },
00083     { "PI",  M_PI  },
00084     { "PHI", M_PHI },
00085 };
00086 
00087 double av_strtod(const char *numstr, char **tail)
00088 {
00089     double d;
00090     char *next;
00091     if(numstr[0]=='0' && (numstr[1]|0x20)=='x') {
00092         d = strtoul(numstr, &next, 16);
00093     } else
00094         d = strtod(numstr, &next);
00095     /* if parsing succeeded, check for and interpret postfixes */
00096     if (next!=numstr) {
00097         if (*next >= 'E' && *next <= 'z') {
00098             int e= si_prefixes[*next - 'E'];
00099             if (e) {
00100                 if (next[1] == 'i') {
00101                     d*= pow( 2, e/0.3);
00102                     next+=2;
00103                 } else {
00104                     d*= pow(10, e);
00105                     next++;
00106                 }
00107             }
00108         }
00109 
00110         if (*next=='B') {
00111             d*=8;
00112             next++;
00113         }
00114     }
00115     /* if requested, fill in tail with the position after the last parsed
00116        character */
00117     if (tail)
00118         *tail = next;
00119     return d;
00120 }
00121 
00122 #define IS_IDENTIFIER_CHAR(c) ((c) - '0' <= 9U || (c) - 'a' <= 25U || (c) - 'A' <= 25U || (c) == '_')
00123 
00124 static int strmatch(const char *s, const char *prefix)
00125 {
00126     int i;
00127     for (i=0; prefix[i]; i++) {
00128         if (prefix[i] != s[i]) return 0;
00129     }
00130     /* return 1 only if the s identifier is terminated */
00131     return !IS_IDENTIFIER_CHAR(s[i]);
00132 }
00133 
00134 struct AVExpr {
00135     enum {
00136         e_value, e_const, e_func0, e_func1, e_func2,
00137         e_squish, e_gauss, e_ld, e_isnan, e_isinf,
00138         e_mod, e_max, e_min, e_eq, e_gt, e_gte,
00139         e_pow, e_mul, e_div, e_add,
00140         e_last, e_st, e_while, e_taylor, e_root, e_floor, e_ceil, e_trunc,
00141         e_sqrt, e_not, e_random, e_hypot, e_gcd,
00142         e_if, e_ifnot,
00143     } type;
00144     double value; // is sign in other types
00145     union {
00146         int const_index;
00147         double (*func0)(double);
00148         double (*func1)(void *, double);
00149         double (*func2)(void *, double, double);
00150     } a;
00151     struct AVExpr *param[3];
00152     double *var;
00153 };
00154 
00155 static double eval_expr(Parser *p, AVExpr *e)
00156 {
00157     switch (e->type) {
00158         case e_value:  return e->value;
00159         case e_const:  return e->value * p->const_values[e->a.const_index];
00160         case e_func0:  return e->value * e->a.func0(eval_expr(p, e->param[0]));
00161         case e_func1:  return e->value * e->a.func1(p->opaque, eval_expr(p, e->param[0]));
00162         case e_func2:  return e->value * e->a.func2(p->opaque, eval_expr(p, e->param[0]), eval_expr(p, e->param[1]));
00163         case e_squish: return 1/(1+exp(4*eval_expr(p, e->param[0])));
00164         case e_gauss: { double d = eval_expr(p, e->param[0]); return exp(-d*d/2)/sqrt(2*M_PI); }
00165         case e_ld:     return e->value * p->var[av_clip(eval_expr(p, e->param[0]), 0, VARS-1)];
00166         case e_isnan:  return e->value * !!isnan(eval_expr(p, e->param[0]));
00167         case e_isinf:  return e->value * !!isinf(eval_expr(p, e->param[0]));
00168         case e_floor:  return e->value * floor(eval_expr(p, e->param[0]));
00169         case e_ceil :  return e->value * ceil (eval_expr(p, e->param[0]));
00170         case e_trunc:  return e->value * trunc(eval_expr(p, e->param[0]));
00171         case e_sqrt:   return e->value * sqrt (eval_expr(p, e->param[0]));
00172         case e_not:    return e->value * (eval_expr(p, e->param[0]) == 0);
00173         case e_if:     return e->value * ( eval_expr(p, e->param[0]) ? eval_expr(p, e->param[1]) : 0);
00174         case e_ifnot:  return e->value * (!eval_expr(p, e->param[0]) ? eval_expr(p, e->param[1]) : 0);
00175         case e_random:{
00176             int idx= av_clip(eval_expr(p, e->param[0]), 0, VARS-1);
00177             uint64_t r= isnan(p->var[idx]) ? 0 : p->var[idx];
00178             r= r*1664525+1013904223;
00179             p->var[idx]= r;
00180             return e->value * (r * (1.0/UINT64_MAX));
00181         }
00182         case e_while: {
00183             double d = NAN;
00184             while (eval_expr(p, e->param[0]))
00185                 d=eval_expr(p, e->param[1]);
00186             return d;
00187         }
00188         case e_taylor: {
00189             double t = 1, d = 0, v;
00190             double x = eval_expr(p, e->param[1]);
00191             int id = e->param[2] ? av_clip(eval_expr(p, e->param[2]), 0, VARS-1) : 0;
00192             int i;
00193             double var0 = p->var[id];
00194             for(i=0; i<1000; i++) {
00195                 double ld = d;
00196                 p->var[id] = i;
00197                 v = eval_expr(p, e->param[0]);
00198                 d += t*v;
00199                 if(ld==d && v)
00200                     break;
00201                 t *= x / (i+1);
00202             }
00203             p->var[id] = var0;
00204             return d;
00205         }
00206         case e_root: {
00207             int i, j;
00208             double low = -1, high = -1, v, low_v = -DBL_MAX, high_v = DBL_MAX;
00209             double var0 = p->var[0];
00210             double x_max = eval_expr(p, e->param[1]);
00211             for(i=-1; i<1024; i++) {
00212                 if(i<255) {
00213                     p->var[0] = av_reverse[i&255]*x_max/255;
00214                 } else {
00215                     p->var[0] = x_max*pow(0.9, i-255);
00216                     if (i&1) p->var[0] *= -1;
00217                     if (i&2) p->var[0] += low;
00218                     else     p->var[0] += high;
00219                 }
00220                 v = eval_expr(p, e->param[0]);
00221                 if (v<=0 && v>low_v) {
00222                     low    = p->var[0];
00223                     low_v  = v;
00224                 }
00225                 if (v>=0 && v<high_v) {
00226                     high   = p->var[0];
00227                     high_v = v;
00228                 }
00229                 if (low>=0 && high>=0){
00230                     for (j=0; j<1000; j++) {
00231                         p->var[0] = (low+high)*0.5;
00232                         if (low == p->var[0] || high == p->var[0])
00233                             break;
00234                         v = eval_expr(p, e->param[0]);
00235                         if (v<=0) low = p->var[0];
00236                         if (v>=0) high= p->var[0];
00237                         if (isnan(v)) {
00238                             low = high = v;
00239                             break;
00240                         }
00241                     }
00242                     break;
00243                 }
00244             }
00245             p->var[0] = var0;
00246             return -low_v<high_v ? low : high;
00247         }
00248         default: {
00249             double d = eval_expr(p, e->param[0]);
00250             double d2 = eval_expr(p, e->param[1]);
00251             switch (e->type) {
00252                 case e_mod: return e->value * (d - floor(d/d2)*d2);
00253                 case e_gcd: return e->value * av_gcd(d,d2);
00254                 case e_max: return e->value * (d >  d2 ?   d : d2);
00255                 case e_min: return e->value * (d <  d2 ?   d : d2);
00256                 case e_eq:  return e->value * (d == d2 ? 1.0 : 0.0);
00257                 case e_gt:  return e->value * (d >  d2 ? 1.0 : 0.0);
00258                 case e_gte: return e->value * (d >= d2 ? 1.0 : 0.0);
00259                 case e_pow: return e->value * pow(d, d2);
00260                 case e_mul: return e->value * (d * d2);
00261                 case e_div: return e->value * (d / d2);
00262                 case e_add: return e->value * (d + d2);
00263                 case e_last:return e->value * d2;
00264                 case e_st : return e->value * (p->var[av_clip(d, 0, VARS-1)]= d2);
00265                 case e_hypot:return e->value * (sqrt(d*d + d2*d2));
00266             }
00267         }
00268     }
00269     return NAN;
00270 }
00271 
00272 static int parse_expr(AVExpr **e, Parser *p);
00273 
00274 void av_expr_free(AVExpr *e)
00275 {
00276     if (!e) return;
00277     av_expr_free(e->param[0]);
00278     av_expr_free(e->param[1]);
00279     av_expr_free(e->param[2]);
00280     av_freep(&e->var);
00281     av_freep(&e);
00282 }
00283 
00284 static int parse_primary(AVExpr **e, Parser *p)
00285 {
00286     AVExpr *d = av_mallocz(sizeof(AVExpr));
00287     char *next = p->s, *s0 = p->s;
00288     int ret, i;
00289 
00290     if (!d)
00291         return AVERROR(ENOMEM);
00292 
00293     /* number */
00294     d->value = av_strtod(p->s, &next);
00295     if (next != p->s) {
00296         d->type = e_value;
00297         p->s= next;
00298         *e = d;
00299         return 0;
00300     }
00301     d->value = 1;
00302 
00303     /* named constants */
00304     for (i=0; p->const_names && p->const_names[i]; i++) {
00305         if (strmatch(p->s, p->const_names[i])) {
00306             p->s+= strlen(p->const_names[i]);
00307             d->type = e_const;
00308             d->a.const_index = i;
00309             *e = d;
00310             return 0;
00311         }
00312     }
00313     for (i = 0; i < FF_ARRAY_ELEMS(constants); i++) {
00314         if (strmatch(p->s, constants[i].name)) {
00315             p->s += strlen(constants[i].name);
00316             d->type = e_value;
00317             d->value = constants[i].value;
00318             *e = d;
00319             return 0;
00320         }
00321     }
00322 
00323     p->s= strchr(p->s, '(');
00324     if (p->s==NULL) {
00325         av_log(p, AV_LOG_ERROR, "Undefined constant or missing '(' in '%s'\n", s0);
00326         p->s= next;
00327         av_expr_free(d);
00328         return AVERROR(EINVAL);
00329     }
00330     p->s++; // "("
00331     if (*next == '(') { // special case do-nothing
00332         av_freep(&d);
00333         if ((ret = parse_expr(&d, p)) < 0)
00334             return ret;
00335         if (p->s[0] != ')') {
00336             av_log(p, AV_LOG_ERROR, "Missing ')' in '%s'\n", s0);
00337             av_expr_free(d);
00338             return AVERROR(EINVAL);
00339         }
00340         p->s++; // ")"
00341         *e = d;
00342         return 0;
00343     }
00344     if ((ret = parse_expr(&(d->param[0]), p)) < 0) {
00345         av_expr_free(d);
00346         return ret;
00347     }
00348     if (p->s[0]== ',') {
00349         p->s++; // ","
00350         parse_expr(&d->param[1], p);
00351     }
00352     if (p->s[0]== ',') {
00353         p->s++; // ","
00354         parse_expr(&d->param[2], p);
00355     }
00356     if (p->s[0] != ')') {
00357         av_log(p, AV_LOG_ERROR, "Missing ')' or too many args in '%s'\n", s0);
00358         av_expr_free(d);
00359         return AVERROR(EINVAL);
00360     }
00361     p->s++; // ")"
00362 
00363     d->type = e_func0;
00364          if (strmatch(next, "sinh"  )) d->a.func0 = sinh;
00365     else if (strmatch(next, "cosh"  )) d->a.func0 = cosh;
00366     else if (strmatch(next, "tanh"  )) d->a.func0 = tanh;
00367     else if (strmatch(next, "sin"   )) d->a.func0 = sin;
00368     else if (strmatch(next, "cos"   )) d->a.func0 = cos;
00369     else if (strmatch(next, "tan"   )) d->a.func0 = tan;
00370     else if (strmatch(next, "atan"  )) d->a.func0 = atan;
00371     else if (strmatch(next, "asin"  )) d->a.func0 = asin;
00372     else if (strmatch(next, "acos"  )) d->a.func0 = acos;
00373     else if (strmatch(next, "exp"   )) d->a.func0 = exp;
00374     else if (strmatch(next, "log"   )) d->a.func0 = log;
00375     else if (strmatch(next, "abs"   )) d->a.func0 = fabs;
00376     else if (strmatch(next, "squish")) d->type = e_squish;
00377     else if (strmatch(next, "gauss" )) d->type = e_gauss;
00378     else if (strmatch(next, "mod"   )) d->type = e_mod;
00379     else if (strmatch(next, "max"   )) d->type = e_max;
00380     else if (strmatch(next, "min"   )) d->type = e_min;
00381     else if (strmatch(next, "eq"    )) d->type = e_eq;
00382     else if (strmatch(next, "gte"   )) d->type = e_gte;
00383     else if (strmatch(next, "gt"    )) d->type = e_gt;
00384     else if (strmatch(next, "lte"   )) { AVExpr *tmp = d->param[1]; d->param[1] = d->param[0]; d->param[0] = tmp; d->type = e_gte; }
00385     else if (strmatch(next, "lt"    )) { AVExpr *tmp = d->param[1]; d->param[1] = d->param[0]; d->param[0] = tmp; d->type = e_gt; }
00386     else if (strmatch(next, "ld"    )) d->type = e_ld;
00387     else if (strmatch(next, "isnan" )) d->type = e_isnan;
00388     else if (strmatch(next, "isinf" )) d->type = e_isinf;
00389     else if (strmatch(next, "st"    )) d->type = e_st;
00390     else if (strmatch(next, "while" )) d->type = e_while;
00391     else if (strmatch(next, "taylor")) d->type = e_taylor;
00392     else if (strmatch(next, "root"  )) d->type = e_root;
00393     else if (strmatch(next, "floor" )) d->type = e_floor;
00394     else if (strmatch(next, "ceil"  )) d->type = e_ceil;
00395     else if (strmatch(next, "trunc" )) d->type = e_trunc;
00396     else if (strmatch(next, "sqrt"  )) d->type = e_sqrt;
00397     else if (strmatch(next, "not"   )) d->type = e_not;
00398     else if (strmatch(next, "pow"   )) d->type = e_pow;
00399     else if (strmatch(next, "random")) d->type = e_random;
00400     else if (strmatch(next, "hypot" )) d->type = e_hypot;
00401     else if (strmatch(next, "gcd"   )) d->type = e_gcd;
00402     else if (strmatch(next, "if"    )) d->type = e_if;
00403     else if (strmatch(next, "ifnot" )) d->type = e_ifnot;
00404     else {
00405         for (i=0; p->func1_names && p->func1_names[i]; i++) {
00406             if (strmatch(next, p->func1_names[i])) {
00407                 d->a.func1 = p->funcs1[i];
00408                 d->type = e_func1;
00409                 *e = d;
00410                 return 0;
00411             }
00412         }
00413 
00414         for (i=0; p->func2_names && p->func2_names[i]; i++) {
00415             if (strmatch(next, p->func2_names[i])) {
00416                 d->a.func2 = p->funcs2[i];
00417                 d->type = e_func2;
00418                 *e = d;
00419                 return 0;
00420             }
00421         }
00422 
00423         av_log(p, AV_LOG_ERROR, "Unknown function in '%s'\n", s0);
00424         av_expr_free(d);
00425         return AVERROR(EINVAL);
00426     }
00427 
00428     *e = d;
00429     return 0;
00430 }
00431 
00432 static AVExpr *new_eval_expr(int type, int value, AVExpr *p0, AVExpr *p1)
00433 {
00434     AVExpr *e = av_mallocz(sizeof(AVExpr));
00435     if (!e)
00436         return NULL;
00437     e->type     =type   ;
00438     e->value    =value  ;
00439     e->param[0] =p0     ;
00440     e->param[1] =p1     ;
00441     return e;
00442 }
00443 
00444 static int parse_pow(AVExpr **e, Parser *p, int *sign)
00445 {
00446     *sign= (*p->s == '+') - (*p->s == '-');
00447     p->s += *sign&1;
00448     return parse_primary(e, p);
00449 }
00450 
00451 static int parse_factor(AVExpr **e, Parser *p)
00452 {
00453     int sign, sign2, ret;
00454     AVExpr *e0, *e1, *e2;
00455     if ((ret = parse_pow(&e0, p, &sign)) < 0)
00456         return ret;
00457     while(p->s[0]=='^'){
00458         e1 = e0;
00459         p->s++;
00460         if ((ret = parse_pow(&e2, p, &sign2)) < 0) {
00461             av_expr_free(e1);
00462             return ret;
00463         }
00464         e0 = new_eval_expr(e_pow, 1, e1, e2);
00465         if (!e0) {
00466             av_expr_free(e1);
00467             av_expr_free(e2);
00468             return AVERROR(ENOMEM);
00469         }
00470         if (e0->param[1]) e0->param[1]->value *= (sign2|1);
00471     }
00472     if (e0) e0->value *= (sign|1);
00473 
00474     *e = e0;
00475     return 0;
00476 }
00477 
00478 static int parse_term(AVExpr **e, Parser *p)
00479 {
00480     int ret;
00481     AVExpr *e0, *e1, *e2;
00482     if ((ret = parse_factor(&e0, p)) < 0)
00483         return ret;
00484     while (p->s[0]=='*' || p->s[0]=='/') {
00485         int c= *p->s++;
00486         e1 = e0;
00487         if ((ret = parse_factor(&e2, p)) < 0) {
00488             av_expr_free(e1);
00489             return ret;
00490         }
00491         e0 = new_eval_expr(c == '*' ? e_mul : e_div, 1, e1, e2);
00492         if (!e0) {
00493             av_expr_free(e1);
00494             av_expr_free(e2);
00495             return AVERROR(ENOMEM);
00496         }
00497     }
00498     *e = e0;
00499     return 0;
00500 }
00501 
00502 static int parse_subexpr(AVExpr **e, Parser *p)
00503 {
00504     int ret;
00505     AVExpr *e0, *e1, *e2;
00506     if ((ret = parse_term(&e0, p)) < 0)
00507         return ret;
00508     while (*p->s == '+' || *p->s == '-') {
00509         e1 = e0;
00510         if ((ret = parse_term(&e2, p)) < 0) {
00511             av_expr_free(e1);
00512             return ret;
00513         }
00514         e0 = new_eval_expr(e_add, 1, e1, e2);
00515         if (!e0) {
00516             av_expr_free(e1);
00517             av_expr_free(e2);
00518             return AVERROR(ENOMEM);
00519         }
00520     };
00521 
00522     *e = e0;
00523     return 0;
00524 }
00525 
00526 static int parse_expr(AVExpr **e, Parser *p)
00527 {
00528     int ret;
00529     AVExpr *e0, *e1, *e2;
00530     if (p->stack_index <= 0) //protect against stack overflows
00531         return AVERROR(EINVAL);
00532     p->stack_index--;
00533 
00534     if ((ret = parse_subexpr(&e0, p)) < 0)
00535         return ret;
00536     while (*p->s == ';') {
00537         p->s++;
00538         e1 = e0;
00539         if ((ret = parse_subexpr(&e2, p)) < 0) {
00540             av_expr_free(e1);
00541             return ret;
00542         }
00543         e0 = new_eval_expr(e_last, 1, e1, e2);
00544         if (!e0) {
00545             av_expr_free(e1);
00546             av_expr_free(e2);
00547             return AVERROR(ENOMEM);
00548         }
00549     };
00550 
00551     p->stack_index++;
00552     *e = e0;
00553     return 0;
00554 }
00555 
00556 static int verify_expr(AVExpr *e)
00557 {
00558     if (!e) return 0;
00559     switch (e->type) {
00560         case e_value:
00561         case e_const: return 1;
00562         case e_func0:
00563         case e_func1:
00564         case e_squish:
00565         case e_ld:
00566         case e_gauss:
00567         case e_isnan:
00568         case e_isinf:
00569         case e_floor:
00570         case e_ceil:
00571         case e_trunc:
00572         case e_sqrt:
00573         case e_not:
00574         case e_random:
00575             return verify_expr(e->param[0]) && !e->param[1];
00576         case e_taylor:
00577             return verify_expr(e->param[0]) && verify_expr(e->param[1])
00578                    && (!e->param[2] || verify_expr(e->param[2]));
00579         default: return verify_expr(e->param[0]) && verify_expr(e->param[1]) && !e->param[2];
00580     }
00581 }
00582 
00583 int av_expr_parse(AVExpr **expr, const char *s,
00584                   const char * const *const_names,
00585                   const char * const *func1_names, double (* const *funcs1)(void *, double),
00586                   const char * const *func2_names, double (* const *funcs2)(void *, double, double),
00587                   int log_offset, void *log_ctx)
00588 {
00589     Parser p = { 0 };
00590     AVExpr *e = NULL;
00591     char *w = av_malloc(strlen(s) + 1);
00592     char *wp = w;
00593     const char *s0 = s;
00594     int ret = 0;
00595 
00596     if (!w)
00597         return AVERROR(ENOMEM);
00598 
00599     while (*s)
00600         if (!isspace(*s++)) *wp++ = s[-1];
00601     *wp++ = 0;
00602 
00603     p.class      = &class;
00604     p.stack_index=100;
00605     p.s= w;
00606     p.const_names = const_names;
00607     p.funcs1      = funcs1;
00608     p.func1_names = func1_names;
00609     p.funcs2      = funcs2;
00610     p.func2_names = func2_names;
00611     p.log_offset = log_offset;
00612     p.log_ctx    = log_ctx;
00613 
00614     if ((ret = parse_expr(&e, &p)) < 0)
00615         goto end;
00616     if (*p.s) {
00617         av_expr_free(e);
00618         av_log(&p, AV_LOG_ERROR, "Invalid chars '%s' at the end of expression '%s'\n", p.s, s0);
00619         ret = AVERROR(EINVAL);
00620         goto end;
00621     }
00622     if (!verify_expr(e)) {
00623         av_expr_free(e);
00624         ret = AVERROR(EINVAL);
00625         goto end;
00626     }
00627     e->var= av_mallocz(sizeof(double) *VARS);
00628     *expr = e;
00629 end:
00630     av_free(w);
00631     return ret;
00632 }
00633 
00634 double av_expr_eval(AVExpr *e, const double *const_values, void *opaque)
00635 {
00636     Parser p = { 0 };
00637     p.var= e->var;
00638 
00639     p.const_values = const_values;
00640     p.opaque     = opaque;
00641     return eval_expr(&p, e);
00642 }
00643 
00644 int av_expr_parse_and_eval(double *d, const char *s,
00645                            const char * const *const_names, const double *const_values,
00646                            const char * const *func1_names, double (* const *funcs1)(void *, double),
00647                            const char * const *func2_names, double (* const *funcs2)(void *, double, double),
00648                            void *opaque, int log_offset, void *log_ctx)
00649 {
00650     AVExpr *e = NULL;
00651     int ret = av_expr_parse(&e, s, const_names, func1_names, funcs1, func2_names, funcs2, log_offset, log_ctx);
00652 
00653     if (ret < 0) {
00654         *d = NAN;
00655         return ret;
00656     }
00657     *d = av_expr_eval(e, const_values, opaque);
00658     av_expr_free(e);
00659     return isnan(*d) ? AVERROR(EINVAL) : 0;
00660 }
00661 
00662 #if FF_API_OLD_EVAL_NAMES
00663 // LCOV_EXCL_START
00664 int av_parse_expr(AVExpr **expr, const char *s,
00665                   const char * const *const_names,
00666                   const char * const *func1_names, double (* const *funcs1)(void *, double),
00667                   const char * const *func2_names, double (* const *funcs2)(void *, double, double),
00668                   int log_offset, void *log_ctx)
00669 {
00670     return av_expr_parse(expr, s, const_names, func1_names, funcs1, func2_names, funcs2,
00671                       log_offset, log_ctx);
00672 }
00673 
00674 double av_eval_expr(AVExpr *e, const double *const_values, void *opaque)
00675 {
00676     return av_expr_eval(e, const_values, opaque);
00677 }
00678 
00679 int av_parse_and_eval_expr(double *res, const char *s,
00680                            const char * const *const_names, const double *const_values,
00681                            const char * const *func1_names, double (* const *funcs1)(void *, double),
00682                            const char * const *func2_names, double (* const *funcs2)(void *, double, double),
00683                            void *opaque, int log_offset, void *log_ctx)
00684 {
00685     return av_expr_parse_and_eval(res, s, const_names, const_values, func1_names, funcs1, func2_names, funcs2,
00686                                   opaque, log_offset, log_ctx);
00687 }
00688 
00689 void av_free_expr(AVExpr *e)
00690 {
00691     av_expr_free(e);
00692 }
00693 // LCOV_EXCL_STOP
00694 #endif /* FF_API_OLD_EVAL_NAMES */
00695 
00696 #ifdef TEST
00697 // LCOV_EXCL_START
00698 #undef printf
00699 #include <string.h>
00700 
00701 static const double const_values[] = {
00702     M_PI,
00703     M_E,
00704     0
00705 };
00706 
00707 static const char *const const_names[] = {
00708     "PI",
00709     "E",
00710     0
00711 };
00712 
00713 int main(int argc, char **argv)
00714 {
00715     int i;
00716     double d;
00717     const char **expr, *exprs[] = {
00718         "",
00719         "1;2",
00720         "-20",
00721         "-PI",
00722         "+PI",
00723         "1+(5-2)^(3-1)+1/2+sin(PI)-max(-2.2,-3.1)",
00724         "80G/80Gi",
00725         "1k",
00726         "1Gi",
00727         "1gi",
00728         "1GiFoo",
00729         "1k+1k",
00730         "1Gi*3foo",
00731         "foo",
00732         "foo(",
00733         "foo()",
00734         "foo)",
00735         "sin",
00736         "sin(",
00737         "sin()",
00738         "sin)",
00739         "sin 10",
00740         "sin(1,2,3)",
00741         "sin(1 )",
00742         "1",
00743         "1foo",
00744         "bar + PI + E + 100f*2 + foo",
00745         "13k + 12f - foo(1, 2)",
00746         "1gi",
00747         "1Gi",
00748         "st(0, 123)",
00749         "st(1, 123); ld(1)",
00750         "lte(0, 1)",
00751         "lte(1, 1)",
00752         "lte(1, 0)",
00753         "lt(0, 1)",
00754         "lt(1, 1)",
00755         "gt(1, 0)",
00756         "gt(2, 7)",
00757         "gte(122, 122)",
00758         /* compute 1+2+...+N */
00759         "st(0, 1); while(lte(ld(0), 100), st(1, ld(1)+ld(0));st(0, ld(0)+1)); ld(1)",
00760         /* compute Fib(N) */
00761         "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)",
00762         "while(0, 10)",
00763         "st(0, 1); while(lte(ld(0),100), st(1, ld(1)+ld(0)); st(0, ld(0)+1))",
00764         "isnan(1)",
00765         "isnan(NAN)",
00766         "isnan(INF)",
00767         "isinf(1)",
00768         "isinf(NAN)",
00769         "isinf(INF)",
00770         "floor(NAN)",
00771         "floor(123.123)",
00772         "floor(-123.123)",
00773         "trunc(123.123)",
00774         "trunc(-123.123)",
00775         "ceil(123.123)",
00776         "ceil(-123.123)",
00777         "sqrt(1764)",
00778         "isnan(sqrt(-1))",
00779         "not(1)",
00780         "not(NAN)",
00781         "not(0)",
00782         "pow(0,1.23)",
00783         "pow(PI,1.23)",
00784         "PI^1.23",
00785         "pow(-1,1.23)",
00786         "if(1, 2)",
00787         "ifnot(0, 23)",
00788         "ifnot(1, NaN) + if(0, 1)",
00789         "taylor(1, 1)",
00790         "taylor(eq(mod(ld(1),4),1)-eq(mod(ld(1),4),3), PI/2, 1)",
00791         "root(sin(ld(0))-1, 2)",
00792         "root(sin(ld(0))+6+sin(ld(0)/12)-log(ld(0)), 100)",
00793         NULL
00794     };
00795 
00796     for (expr = exprs; *expr; expr++) {
00797         printf("Evaluating '%s'\n", *expr);
00798         av_expr_parse_and_eval(&d, *expr,
00799                                const_names, const_values,
00800                                NULL, NULL, NULL, NULL, NULL, 0, NULL);
00801         if (isnan(d))
00802             printf("'%s' -> nan\n\n", *expr);
00803         else
00804             printf("'%s' -> %f\n\n", *expr, d);
00805     }
00806 
00807     av_expr_parse_and_eval(&d, "1+(5-2)^(3-1)+1/2+sin(PI)-max(-2.2,-3.1)",
00808                            const_names, const_values,
00809                            NULL, NULL, NULL, NULL, NULL, 0, NULL);
00810     printf("%f == 12.7\n", d);
00811     av_expr_parse_and_eval(&d, "80G/80Gi",
00812                            const_names, const_values,
00813                            NULL, NULL, NULL, NULL, NULL, 0, NULL);
00814     printf("%f == 0.931322575\n", d);
00815 
00816     if (argc > 1 && !strcmp(argv[1], "-t")) {
00817         for (i = 0; i < 1050; i++) {
00818             START_TIMER;
00819             av_expr_parse_and_eval(&d, "1+(5-2)^(3-1)+1/2+sin(PI)-max(-2.2,-3.1)",
00820                                    const_names, const_values,
00821                                    NULL, NULL, NULL, NULL, NULL, 0, NULL);
00822             STOP_TIMER("av_expr_parse_and_eval");
00823         }
00824     }
00825 
00826     return 0;
00827 }
00828 // LCOV_EXCL_STOP
00829 #endif