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-rw-r--r--media/ffvpx/libavutil/eval.c792
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diff --git a/media/ffvpx/libavutil/eval.c b/media/ffvpx/libavutil/eval.c
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+++ b/media/ffvpx/libavutil/eval.c
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+/*
+ * Copyright (c) 2002-2006 Michael Niedermayer <michaelni@gmx.at>
+ * Copyright (c) 2006 Oded Shimon <ods15@ods15.dyndns.org>
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+/**
+ * @file
+ * simple arithmetic expression evaluator.
+ *
+ * see http://joe.hotchkiss.com/programming/eval/eval.html
+ */
+
+#include <float.h>
+#include "attributes.h"
+#include "avutil.h"
+#include "common.h"
+#include "eval.h"
+#include "ffmath.h"
+#include "internal.h"
+#include "log.h"
+#include "mathematics.h"
+#include "fftime.h"
+#include "avstring.h"
+#include "timer.h"
+#include "reverse.h"
+
+typedef struct Parser {
+ const AVClass *class;
+ int stack_index;
+ char *s;
+ const double *const_values;
+ const char * const *const_names; // NULL terminated
+ double (* const *funcs1)(void *, double a); // NULL terminated
+ const char * const *func1_names; // NULL terminated
+ double (* const *funcs2)(void *, double a, double b); // NULL terminated
+ const char * const *func2_names; // NULL terminated
+ void *opaque;
+ int log_offset;
+ void *log_ctx;
+#define VARS 10
+ double *var;
+} Parser;
+
+static const AVClass eval_class = {
+ .class_name = "Eval",
+ .item_name = av_default_item_name,
+ .option = NULL,
+ .version = LIBAVUTIL_VERSION_INT,
+ .log_level_offset_offset = offsetof(Parser, log_offset),
+ .parent_log_context_offset = offsetof(Parser, log_ctx),
+};
+
+static const struct {
+ double bin_val;
+ double dec_val;
+ int8_t exp;
+} si_prefixes['z' - 'E' + 1] = {
+ ['y'-'E']= { 8.271806125530276749e-25, 1e-24, -24 },
+ ['z'-'E']= { 8.4703294725430034e-22, 1e-21, -21 },
+ ['a'-'E']= { 8.6736173798840355e-19, 1e-18, -18 },
+ ['f'-'E']= { 8.8817841970012523e-16, 1e-15, -15 },
+ ['p'-'E']= { 9.0949470177292824e-13, 1e-12, -12 },
+ ['n'-'E']= { 9.3132257461547852e-10, 1e-9, -9 },
+ ['u'-'E']= { 9.5367431640625e-7, 1e-6, -6 },
+ ['m'-'E']= { 9.765625e-4, 1e-3, -3 },
+ ['c'-'E']= { 9.8431332023036951e-3, 1e-2, -2 },
+ ['d'-'E']= { 9.921256574801246e-2, 1e-1, -1 },
+ ['h'-'E']= { 1.0159366732596479e2, 1e2, 2 },
+ ['k'-'E']= { 1.024e3, 1e3, 3 },
+ ['K'-'E']= { 1.024e3, 1e3, 3 },
+ ['M'-'E']= { 1.048576e6, 1e6, 6 },
+ ['G'-'E']= { 1.073741824e9, 1e9, 9 },
+ ['T'-'E']= { 1.099511627776e12, 1e12, 12 },
+ ['P'-'E']= { 1.125899906842624e15, 1e15, 15 },
+ ['E'-'E']= { 1.152921504606847e18, 1e18, 18 },
+ ['Z'-'E']= { 1.1805916207174113e21, 1e21, 21 },
+ ['Y'-'E']= { 1.2089258196146292e24, 1e24, 24 },
+};
+
+static const struct {
+ const char *name;
+ double value;
+} constants[] = {
+ { "E", M_E },
+ { "PI", M_PI },
+ { "PHI", M_PHI },
+ { "QP2LAMBDA", FF_QP2LAMBDA },
+};
+
+double av_strtod(const char *numstr, char **tail)
+{
+ double d;
+ char *next;
+ if(numstr[0]=='0' && (numstr[1]|0x20)=='x') {
+ d = strtoul(numstr, &next, 16);
+ } else
+ d = strtod(numstr, &next);
+ /* if parsing succeeded, check for and interpret postfixes */
+ if (next!=numstr) {
+ if (next[0] == 'd' && next[1] == 'B') {
+ /* treat dB as decibels instead of decibytes */
+ d = ff_exp10(d / 20);
+ next += 2;
+ } else if (*next >= 'E' && *next <= 'z') {
+ int e= si_prefixes[*next - 'E'].exp;
+ if (e) {
+ if (next[1] == 'i') {
+ d*= si_prefixes[*next - 'E'].bin_val;
+ next+=2;
+ } else {
+ d*= si_prefixes[*next - 'E'].dec_val;
+ next++;
+ }
+ }
+ }
+
+ if (*next=='B') {
+ d*=8;
+ next++;
+ }
+ }
+ /* if requested, fill in tail with the position after the last parsed
+ character */
+ if (tail)
+ *tail = next;
+ return d;
+}
+
+#define IS_IDENTIFIER_CHAR(c) ((c) - '0' <= 9U || (c) - 'a' <= 25U || (c) - 'A' <= 25U || (c) == '_')
+
+static int strmatch(const char *s, const char *prefix)
+{
+ int i;
+ for (i=0; prefix[i]; i++) {
+ if (prefix[i] != s[i]) return 0;
+ }
+ /* return 1 only if the s identifier is terminated */
+ return !IS_IDENTIFIER_CHAR(s[i]);
+}
+
+struct AVExpr {
+ enum {
+ e_value, e_const, e_func0, e_func1, e_func2,
+ e_squish, e_gauss, e_ld, e_isnan, e_isinf,
+ e_mod, e_max, e_min, e_eq, e_gt, e_gte, e_lte, e_lt,
+ e_pow, e_mul, e_div, e_add,
+ e_last, e_st, e_while, e_taylor, e_root, e_floor, e_ceil, e_trunc, e_round,
+ e_sqrt, e_not, e_random, e_hypot, e_gcd,
+ e_if, e_ifnot, e_print, e_bitand, e_bitor, e_between, e_clip, e_atan2, e_lerp,
+ e_sgn,
+ } type;
+ double value; // is sign in other types
+ int const_index;
+ union {
+ double (*func0)(double);
+ double (*func1)(void *, double);
+ double (*func2)(void *, double, double);
+ } a;
+ struct AVExpr *param[3];
+ double *var;
+};
+
+static double etime(double v)
+{
+ return av_gettime() * 0.000001;
+}
+
+static double eval_expr(Parser *p, AVExpr *e)
+{
+ switch (e->type) {
+ case e_value: return e->value;
+ case e_const: return e->value * p->const_values[e->const_index];
+ case e_func0: return e->value * e->a.func0(eval_expr(p, e->param[0]));
+ case e_func1: return e->value * e->a.func1(p->opaque, eval_expr(p, e->param[0]));
+ case e_func2: return e->value * e->a.func2(p->opaque, eval_expr(p, e->param[0]), eval_expr(p, e->param[1]));
+ case e_squish: return 1/(1+exp(4*eval_expr(p, e->param[0])));
+ case e_gauss: { double d = eval_expr(p, e->param[0]); return exp(-d*d/2)/sqrt(2*M_PI); }
+ case e_ld: return e->value * p->var[av_clip(eval_expr(p, e->param[0]), 0, VARS-1)];
+ case e_isnan: return e->value * !!isnan(eval_expr(p, e->param[0]));
+ case e_isinf: return e->value * !!isinf(eval_expr(p, e->param[0]));
+ case e_floor: return e->value * floor(eval_expr(p, e->param[0]));
+ case e_ceil : return e->value * ceil (eval_expr(p, e->param[0]));
+ case e_trunc: return e->value * trunc(eval_expr(p, e->param[0]));
+ case e_round: return e->value * round(eval_expr(p, e->param[0]));
+ case e_sgn: return e->value * FFDIFFSIGN(eval_expr(p, e->param[0]), 0);
+ case e_sqrt: return e->value * sqrt (eval_expr(p, e->param[0]));
+ case e_not: return e->value * (eval_expr(p, e->param[0]) == 0);
+ case e_if: return e->value * (eval_expr(p, e->param[0]) ? eval_expr(p, e->param[1]) :
+ e->param[2] ? eval_expr(p, e->param[2]) : 0);
+ case e_ifnot: return e->value * (!eval_expr(p, e->param[0]) ? eval_expr(p, e->param[1]) :
+ e->param[2] ? eval_expr(p, e->param[2]) : 0);
+ case e_clip: {
+ double x = eval_expr(p, e->param[0]);
+ double min = eval_expr(p, e->param[1]), max = eval_expr(p, e->param[2]);
+ if (isnan(min) || isnan(max) || isnan(x) || min > max)
+ return NAN;
+ return e->value * av_clipd(eval_expr(p, e->param[0]), min, max);
+ }
+ case e_between: {
+ double d = eval_expr(p, e->param[0]);
+ return e->value * (d >= eval_expr(p, e->param[1]) &&
+ d <= eval_expr(p, e->param[2]));
+ }
+ case e_lerp: {
+ double v0 = eval_expr(p, e->param[0]);
+ double v1 = eval_expr(p, e->param[1]);
+ double f = eval_expr(p, e->param[2]);
+ return v0 + (v1 - v0) * f;
+ }
+ case e_print: {
+ double x = eval_expr(p, e->param[0]);
+ int level = e->param[1] ? av_clip(eval_expr(p, e->param[1]), INT_MIN, INT_MAX) : AV_LOG_INFO;
+ av_log(p, level, "%f\n", x);
+ return x;
+ }
+ case e_random:{
+ int idx= av_clip(eval_expr(p, e->param[0]), 0, VARS-1);
+ uint64_t r= isnan(p->var[idx]) ? 0 : p->var[idx];
+ r= r*1664525+1013904223;
+ p->var[idx]= r;
+ return e->value * (r * (1.0/UINT64_MAX));
+ }
+ case e_while: {
+ double d = NAN;
+ while (eval_expr(p, e->param[0]))
+ d=eval_expr(p, e->param[1]);
+ return d;
+ }
+ case e_taylor: {
+ double t = 1, d = 0, v;
+ double x = eval_expr(p, e->param[1]);
+ int id = e->param[2] ? av_clip(eval_expr(p, e->param[2]), 0, VARS-1) : 0;
+ int i;
+ double var0 = p->var[id];
+ for(i=0; i<1000; i++) {
+ double ld = d;
+ p->var[id] = i;
+ v = eval_expr(p, e->param[0]);
+ d += t*v;
+ if(ld==d && v)
+ break;
+ t *= x / (i+1);
+ }
+ p->var[id] = var0;
+ return d;
+ }
+ case e_root: {
+ int i, j;
+ double low = -1, high = -1, v, low_v = -DBL_MAX, high_v = DBL_MAX;
+ double var0 = p->var[0];
+ double x_max = eval_expr(p, e->param[1]);
+ for(i=-1; i<1024; i++) {
+ if(i<255) {
+ p->var[0] = ff_reverse[i&255]*x_max/255;
+ } else {
+ p->var[0] = x_max*pow(0.9, i-255);
+ if (i&1) p->var[0] *= -1;
+ if (i&2) p->var[0] += low;
+ else p->var[0] += high;
+ }
+ v = eval_expr(p, e->param[0]);
+ if (v<=0 && v>low_v) {
+ low = p->var[0];
+ low_v = v;
+ }
+ if (v>=0 && v<high_v) {
+ high = p->var[0];
+ high_v = v;
+ }
+ if (low>=0 && high>=0){
+ for (j=0; j<1000; j++) {
+ p->var[0] = (low+high)*0.5;
+ if (low == p->var[0] || high == p->var[0])
+ break;
+ v = eval_expr(p, e->param[0]);
+ if (v<=0) low = p->var[0];
+ if (v>=0) high= p->var[0];
+ if (isnan(v)) {
+ low = high = v;
+ break;
+ }
+ }
+ break;
+ }
+ }
+ p->var[0] = var0;
+ return -low_v<high_v ? low : high;
+ }
+ default: {
+ double d = eval_expr(p, e->param[0]);
+ double d2 = eval_expr(p, e->param[1]);
+ switch (e->type) {
+ case e_mod: return e->value * (d - floor(d2 ? d / d2 : d * INFINITY) * d2);
+ case e_gcd: return e->value * av_gcd(d,d2);
+ case e_max: return e->value * (d > d2 ? d : d2);
+ case e_min: return e->value * (d < d2 ? d : d2);
+ case e_eq: return e->value * (d == d2 ? 1.0 : 0.0);
+ case e_gt: return e->value * (d > d2 ? 1.0 : 0.0);
+ case e_gte: return e->value * (d >= d2 ? 1.0 : 0.0);
+ case e_lt: return e->value * (d < d2 ? 1.0 : 0.0);
+ case e_lte: return e->value * (d <= d2 ? 1.0 : 0.0);
+ case e_pow: return e->value * pow(d, d2);
+ case e_mul: return e->value * (d * d2);
+ case e_div: return e->value * (d2 ? (d / d2) : d * INFINITY);
+ case e_add: return e->value * (d + d2);
+ case e_last:return e->value * d2;
+ case e_st : return e->value * (p->var[av_clip(d, 0, VARS-1)]= d2);
+ case e_hypot:return e->value * hypot(d, d2);
+ case e_atan2:return e->value * atan2(d, d2);
+ case e_bitand: return isnan(d) || isnan(d2) ? NAN : e->value * ((long int)d & (long int)d2);
+ case e_bitor: return isnan(d) || isnan(d2) ? NAN : e->value * ((long int)d | (long int)d2);
+ }
+ }
+ }
+ return NAN;
+}
+
+static int parse_expr(AVExpr **e, Parser *p);
+
+void av_expr_free(AVExpr *e)
+{
+ if (!e) return;
+ av_expr_free(e->param[0]);
+ av_expr_free(e->param[1]);
+ av_expr_free(e->param[2]);
+ av_freep(&e->var);
+ av_freep(&e);
+}
+
+static int parse_primary(AVExpr **e, Parser *p)
+{
+ AVExpr *d = av_mallocz(sizeof(AVExpr));
+ char *next = p->s, *s0 = p->s;
+ int ret, i;
+
+ if (!d)
+ return AVERROR(ENOMEM);
+
+ /* number */
+ d->value = av_strtod(p->s, &next);
+ if (next != p->s) {
+ d->type = e_value;
+ p->s= next;
+ *e = d;
+ return 0;
+ }
+ d->value = 1;
+
+ /* named constants */
+ for (i=0; p->const_names && p->const_names[i]; i++) {
+ if (strmatch(p->s, p->const_names[i])) {
+ p->s+= strlen(p->const_names[i]);
+ d->type = e_const;
+ d->const_index = i;
+ *e = d;
+ return 0;
+ }
+ }
+ for (i = 0; i < FF_ARRAY_ELEMS(constants); i++) {
+ if (strmatch(p->s, constants[i].name)) {
+ p->s += strlen(constants[i].name);
+ d->type = e_value;
+ d->value = constants[i].value;
+ *e = d;
+ return 0;
+ }
+ }
+
+ p->s= strchr(p->s, '(');
+ if (!p->s) {
+ av_log(p, AV_LOG_ERROR, "Undefined constant or missing '(' in '%s'\n", s0);
+ p->s= next;
+ av_expr_free(d);
+ return AVERROR(EINVAL);
+ }
+ p->s++; // "("
+ if (*next == '(') { // special case do-nothing
+ av_freep(&d);
+ if ((ret = parse_expr(&d, p)) < 0)
+ return ret;
+ if (p->s[0] != ')') {
+ av_log(p, AV_LOG_ERROR, "Missing ')' in '%s'\n", s0);
+ av_expr_free(d);
+ return AVERROR(EINVAL);
+ }
+ p->s++; // ")"
+ *e = d;
+ return 0;
+ }
+ if ((ret = parse_expr(&(d->param[0]), p)) < 0) {
+ av_expr_free(d);
+ return ret;
+ }
+ if (p->s[0]== ',') {
+ p->s++; // ","
+ parse_expr(&d->param[1], p);
+ }
+ if (p->s[0]== ',') {
+ p->s++; // ","
+ parse_expr(&d->param[2], p);
+ }
+ if (p->s[0] != ')') {
+ av_log(p, AV_LOG_ERROR, "Missing ')' or too many args in '%s'\n", s0);
+ av_expr_free(d);
+ return AVERROR(EINVAL);
+ }
+ p->s++; // ")"
+
+ d->type = e_func0;
+ if (strmatch(next, "sinh" )) d->a.func0 = sinh;
+ else if (strmatch(next, "cosh" )) d->a.func0 = cosh;
+ else if (strmatch(next, "tanh" )) d->a.func0 = tanh;
+ else if (strmatch(next, "sin" )) d->a.func0 = sin;
+ else if (strmatch(next, "cos" )) d->a.func0 = cos;
+ else if (strmatch(next, "tan" )) d->a.func0 = tan;
+ else if (strmatch(next, "atan" )) d->a.func0 = atan;
+ else if (strmatch(next, "asin" )) d->a.func0 = asin;
+ else if (strmatch(next, "acos" )) d->a.func0 = acos;
+ else if (strmatch(next, "exp" )) d->a.func0 = exp;
+ else if (strmatch(next, "log" )) d->a.func0 = log;
+ else if (strmatch(next, "abs" )) d->a.func0 = fabs;
+ else if (strmatch(next, "time" )) d->a.func0 = etime;
+ else if (strmatch(next, "squish")) d->type = e_squish;
+ else if (strmatch(next, "gauss" )) d->type = e_gauss;
+ else if (strmatch(next, "mod" )) d->type = e_mod;
+ else if (strmatch(next, "max" )) d->type = e_max;
+ else if (strmatch(next, "min" )) d->type = e_min;
+ else if (strmatch(next, "eq" )) d->type = e_eq;
+ else if (strmatch(next, "gte" )) d->type = e_gte;
+ else if (strmatch(next, "gt" )) d->type = e_gt;
+ else if (strmatch(next, "lte" )) d->type = e_lte;
+ else if (strmatch(next, "lt" )) d->type = e_lt;
+ else if (strmatch(next, "ld" )) d->type = e_ld;
+ else if (strmatch(next, "isnan" )) d->type = e_isnan;
+ else if (strmatch(next, "isinf" )) d->type = e_isinf;
+ else if (strmatch(next, "st" )) d->type = e_st;
+ else if (strmatch(next, "while" )) d->type = e_while;
+ else if (strmatch(next, "taylor")) d->type = e_taylor;
+ else if (strmatch(next, "root" )) d->type = e_root;
+ else if (strmatch(next, "floor" )) d->type = e_floor;
+ else if (strmatch(next, "ceil" )) d->type = e_ceil;
+ else if (strmatch(next, "trunc" )) d->type = e_trunc;
+ else if (strmatch(next, "round" )) d->type = e_round;
+ else if (strmatch(next, "sqrt" )) d->type = e_sqrt;
+ else if (strmatch(next, "not" )) d->type = e_not;
+ else if (strmatch(next, "pow" )) d->type = e_pow;
+ else if (strmatch(next, "print" )) d->type = e_print;
+ else if (strmatch(next, "random")) d->type = e_random;
+ else if (strmatch(next, "hypot" )) d->type = e_hypot;
+ else if (strmatch(next, "gcd" )) d->type = e_gcd;
+ else if (strmatch(next, "if" )) d->type = e_if;
+ else if (strmatch(next, "ifnot" )) d->type = e_ifnot;
+ else if (strmatch(next, "bitand")) d->type = e_bitand;
+ else if (strmatch(next, "bitor" )) d->type = e_bitor;
+ else if (strmatch(next, "between"))d->type = e_between;
+ else if (strmatch(next, "clip" )) d->type = e_clip;
+ else if (strmatch(next, "atan2" )) d->type = e_atan2;
+ else if (strmatch(next, "lerp" )) d->type = e_lerp;
+ else if (strmatch(next, "sgn" )) d->type = e_sgn;
+ else {
+ for (i=0; p->func1_names && p->func1_names[i]; i++) {
+ if (strmatch(next, p->func1_names[i])) {
+ d->a.func1 = p->funcs1[i];
+ d->type = e_func1;
+ d->const_index = i;
+ *e = d;
+ return 0;
+ }
+ }
+
+ for (i=0; p->func2_names && p->func2_names[i]; i++) {
+ if (strmatch(next, p->func2_names[i])) {
+ d->a.func2 = p->funcs2[i];
+ d->type = e_func2;
+ d->const_index = i;
+ *e = d;
+ return 0;
+ }
+ }
+
+ av_log(p, AV_LOG_ERROR, "Unknown function in '%s'\n", s0);
+ av_expr_free(d);
+ return AVERROR(EINVAL);
+ }
+
+ *e = d;
+ return 0;
+}
+
+static AVExpr *make_eval_expr(int type, int value, AVExpr *p0, AVExpr *p1)
+{
+ AVExpr *e = av_mallocz(sizeof(AVExpr));
+ if (!e)
+ return NULL;
+ e->type =type ;
+ e->value =value ;
+ e->param[0] =p0 ;
+ e->param[1] =p1 ;
+ return e;
+}
+
+static int parse_pow(AVExpr **e, Parser *p, int *sign)
+{
+ *sign= (*p->s == '+') - (*p->s == '-');
+ p->s += *sign&1;
+ return parse_primary(e, p);
+}
+
+static int parse_dB(AVExpr **e, Parser *p, int *sign)
+{
+ /* do not filter out the negative sign when parsing a dB value.
+ for example, -3dB is not the same as -(3dB) */
+ if (*p->s == '-') {
+ char *next;
+ double av_unused ignored = strtod(p->s, &next);
+ if (next != p->s && next[0] == 'd' && next[1] == 'B') {
+ *sign = 0;
+ return parse_primary(e, p);
+ }
+ }
+ return parse_pow(e, p, sign);
+}
+
+static int parse_factor(AVExpr **e, Parser *p)
+{
+ int sign, sign2, ret;
+ AVExpr *e0, *e1, *e2;
+ if ((ret = parse_dB(&e0, p, &sign)) < 0)
+ return ret;
+ while(p->s[0]=='^'){
+ e1 = e0;
+ p->s++;
+ if ((ret = parse_dB(&e2, p, &sign2)) < 0) {
+ av_expr_free(e1);
+ return ret;
+ }
+ e0 = make_eval_expr(e_pow, 1, e1, e2);
+ if (!e0) {
+ av_expr_free(e1);
+ av_expr_free(e2);
+ return AVERROR(ENOMEM);
+ }
+ if (e0->param[1]) e0->param[1]->value *= (sign2|1);
+ }
+ if (e0) e0->value *= (sign|1);
+
+ *e = e0;
+ return 0;
+}
+
+static int parse_term(AVExpr **e, Parser *p)
+{
+ int ret;
+ AVExpr *e0, *e1, *e2;
+ if ((ret = parse_factor(&e0, p)) < 0)
+ return ret;
+ while (p->s[0]=='*' || p->s[0]=='/') {
+ int c= *p->s++;
+ e1 = e0;
+ if ((ret = parse_factor(&e2, p)) < 0) {
+ av_expr_free(e1);
+ return ret;
+ }
+ e0 = make_eval_expr(c == '*' ? e_mul : e_div, 1, e1, e2);
+ if (!e0) {
+ av_expr_free(e1);
+ av_expr_free(e2);
+ return AVERROR(ENOMEM);
+ }
+ }
+ *e = e0;
+ return 0;
+}
+
+static int parse_subexpr(AVExpr **e, Parser *p)
+{
+ int ret;
+ AVExpr *e0, *e1, *e2;
+ if ((ret = parse_term(&e0, p)) < 0)
+ return ret;
+ while (*p->s == '+' || *p->s == '-') {
+ e1 = e0;
+ if ((ret = parse_term(&e2, p)) < 0) {
+ av_expr_free(e1);
+ return ret;
+ }
+ e0 = make_eval_expr(e_add, 1, e1, e2);
+ if (!e0) {
+ av_expr_free(e1);
+ av_expr_free(e2);
+ return AVERROR(ENOMEM);
+ }
+ };
+
+ *e = e0;
+ return 0;
+}
+
+static int parse_expr(AVExpr **e, Parser *p)
+{
+ int ret;
+ AVExpr *e0, *e1, *e2;
+ if (p->stack_index <= 0) //protect against stack overflows
+ return AVERROR(EINVAL);
+ p->stack_index--;
+
+ if ((ret = parse_subexpr(&e0, p)) < 0)
+ return ret;
+ while (*p->s == ';') {
+ p->s++;
+ e1 = e0;
+ if ((ret = parse_subexpr(&e2, p)) < 0) {
+ av_expr_free(e1);
+ return ret;
+ }
+ e0 = make_eval_expr(e_last, 1, e1, e2);
+ if (!e0) {
+ av_expr_free(e1);
+ av_expr_free(e2);
+ return AVERROR(ENOMEM);
+ }
+ };
+
+ p->stack_index++;
+ *e = e0;
+ return 0;
+}
+
+static int verify_expr(AVExpr *e)
+{
+ if (!e) return 0;
+ switch (e->type) {
+ case e_value:
+ case e_const: return 1;
+ case e_func0:
+ case e_func1:
+ case e_squish:
+ case e_ld:
+ case e_gauss:
+ case e_isnan:
+ case e_isinf:
+ case e_floor:
+ case e_ceil:
+ case e_trunc:
+ case e_round:
+ case e_sqrt:
+ case e_not:
+ case e_random:
+ case e_sgn:
+ return verify_expr(e->param[0]) && !e->param[1];
+ case e_print:
+ return verify_expr(e->param[0])
+ && (!e->param[1] || verify_expr(e->param[1]));
+ case e_if:
+ case e_ifnot:
+ case e_taylor:
+ return verify_expr(e->param[0]) && verify_expr(e->param[1])
+ && (!e->param[2] || verify_expr(e->param[2]));
+ case e_between:
+ case e_clip:
+ case e_lerp:
+ return verify_expr(e->param[0]) &&
+ verify_expr(e->param[1]) &&
+ verify_expr(e->param[2]);
+ default: return verify_expr(e->param[0]) && verify_expr(e->param[1]) && !e->param[2];
+ }
+}
+
+int av_expr_parse(AVExpr **expr, const char *s,
+ const char * const *const_names,
+ const char * const *func1_names, double (* const *funcs1)(void *, double),
+ const char * const *func2_names, double (* const *funcs2)(void *, double, double),
+ int log_offset, void *log_ctx)
+{
+ Parser p = { 0 };
+ AVExpr *e = NULL;
+ char *w = av_malloc(strlen(s) + 1);
+ char *wp = w;
+ const char *s0 = s;
+ int ret = 0;
+
+ if (!w)
+ return AVERROR(ENOMEM);
+
+ while (*s)
+ if (!av_isspace(*s++)) *wp++ = s[-1];
+ *wp++ = 0;
+
+ p.class = &eval_class;
+ p.stack_index=100;
+ p.s= w;
+ p.const_names = const_names;
+ p.funcs1 = funcs1;
+ p.func1_names = func1_names;
+ p.funcs2 = funcs2;
+ p.func2_names = func2_names;
+ p.log_offset = log_offset;
+ p.log_ctx = log_ctx;
+
+ if ((ret = parse_expr(&e, &p)) < 0)
+ goto end;
+ if (*p.s) {
+ av_log(&p, AV_LOG_ERROR, "Invalid chars '%s' at the end of expression '%s'\n", p.s, s0);
+ ret = AVERROR(EINVAL);
+ goto end;
+ }
+ if (!verify_expr(e)) {
+ ret = AVERROR(EINVAL);
+ goto end;
+ }
+ e->var= av_mallocz(sizeof(double) *VARS);
+ if (!e->var) {
+ ret = AVERROR(ENOMEM);
+ goto end;
+ }
+ *expr = e;
+ e = NULL;
+end:
+ av_expr_free(e);
+ av_free(w);
+ return ret;
+}
+
+static int expr_count(AVExpr *e, unsigned *counter, int size, int type)
+{
+ int i;
+
+ if (!e || !counter || !size)
+ return AVERROR(EINVAL);
+
+ for (i = 0; e->type != type && i < 3 && e->param[i]; i++)
+ expr_count(e->param[i], counter, size, type);
+
+ if (e->type == type && e->const_index < size)
+ counter[e->const_index]++;
+
+ return 0;
+}
+
+int av_expr_count_vars(AVExpr *e, unsigned *counter, int size)
+{
+ return expr_count(e, counter, size, e_const);
+}
+
+int av_expr_count_func(AVExpr *e, unsigned *counter, int size, int arg)
+{
+ return expr_count(e, counter, size, ((int[]){e_const, e_func1, e_func2})[arg]);
+}
+
+double av_expr_eval(AVExpr *e, const double *const_values, void *opaque)
+{
+ Parser p = { 0 };
+ p.var= e->var;
+
+ p.const_values = const_values;
+ p.opaque = opaque;
+ return eval_expr(&p, e);
+}
+
+int av_expr_parse_and_eval(double *d, const char *s,
+ const char * const *const_names, const double *const_values,
+ const char * const *func1_names, double (* const *funcs1)(void *, double),
+ const char * const *func2_names, double (* const *funcs2)(void *, double, double),
+ void *opaque, int log_offset, void *log_ctx)
+{
+ AVExpr *e = NULL;
+ int ret = av_expr_parse(&e, s, const_names, func1_names, funcs1, func2_names, funcs2, log_offset, log_ctx);
+
+ if (ret < 0) {
+ *d = NAN;
+ return ret;
+ }
+ *d = av_expr_eval(e, const_values, opaque);
+ av_expr_free(e);
+ return isnan(*d) ? AVERROR(EINVAL) : 0;
+}