FFmpeg/libavutil/eval.c
Reimar Döffinger d086c1203c Add coverage exclusions for test code.
For some of the code e.g. doing timing measurements there is no
real point in running regression testing on it, thus it should
not be counted against coverage.

Signed-off-by: Reimar Döffinger <Reimar.Doeffinger@gmx.de>
2011-12-05 20:05:44 +01:00

731 lines
22 KiB
C

/*
* 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 "avutil.h"
#include "eval.h"
#include "log.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 class = { "Eval", av_default_item_name, NULL, LIBAVUTIL_VERSION_INT, offsetof(Parser,log_offset), offsetof(Parser,log_ctx) };
static const int8_t si_prefixes['z' - 'E' + 1] = {
['y'-'E']= -24,
['z'-'E']= -21,
['a'-'E']= -18,
['f'-'E']= -15,
['p'-'E']= -12,
['n'-'E']= - 9,
['u'-'E']= - 6,
['m'-'E']= - 3,
['c'-'E']= - 2,
['d'-'E']= - 1,
['h'-'E']= 2,
['k'-'E']= 3,
['K'-'E']= 3,
['M'-'E']= 6,
['G'-'E']= 9,
['T'-'E']= 12,
['P'-'E']= 15,
['E'-'E']= 18,
['Z'-'E']= 21,
['Y'-'E']= 24,
};
static const struct {
const char *name;
double value;
} constants[] = {
{ "E", M_E },
{ "PI", M_PI },
{ "PHI", M_PHI },
};
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 >= 'E' && *next <= 'z') {
int e= si_prefixes[*next - 'E'];
if (e) {
if (next[1] == 'i') {
d*= pow( 2, e/0.3);
next+=2;
} else {
d*= pow(10, e);
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_mod, e_max, e_min, e_eq, e_gt, e_gte,
e_pow, e_mul, e_div, e_add,
e_last, e_st, e_while, e_floor, e_ceil, e_trunc,
e_sqrt, e_not, e_random, e_hypot, e_gcd,
} type;
double value; // is sign in other types
union {
int const_index;
double (*func0)(double);
double (*func1)(void *, double);
double (*func2)(void *, double, double);
} a;
struct AVExpr *param[2];
double *var;
};
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->a.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_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_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_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;
}
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(d/d2)*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_pow: return e->value * pow(d, d2);
case e_mul: return e->value * (d * d2);
case e_div: return e->value * (d / d2);
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 * (sqrt(d*d + d2*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_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->a.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==NULL) {
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] != ')') {
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, "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" )) { AVExpr *tmp = d->param[1]; d->param[1] = d->param[0]; d->param[0] = tmp; d->type = e_gt; }
else if (strmatch(next, "lt" )) { AVExpr *tmp = d->param[1]; d->param[1] = d->param[0]; d->param[0] = tmp; d->type = e_gte; }
else if (strmatch(next, "ld" )) d->type = e_ld;
else if (strmatch(next, "isnan" )) d->type = e_isnan;
else if (strmatch(next, "st" )) d->type = e_st;
else if (strmatch(next, "while" )) d->type = e_while;
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, "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, "random")) d->type = e_random;
else if (strmatch(next, "hypot" )) d->type = e_hypot;
else if (strmatch(next, "gcd" )) d->type = e_gcd;
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;
*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;
*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 *new_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_factor(AVExpr **e, Parser *p)
{
int sign, sign2, ret;
AVExpr *e0, *e1, *e2;
if ((ret = parse_pow(&e0, p, &sign)) < 0)
return ret;
while(p->s[0]=='^'){
e1 = e0;
p->s++;
if ((ret = parse_pow(&e2, p, &sign2)) < 0) {
av_expr_free(e1);
return ret;
}
e0 = new_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 = new_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 = new_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 = new_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_floor:
case e_ceil:
case e_trunc:
case e_sqrt:
case e_not:
case e_random:
return verify_expr(e->param[0]);
default: return verify_expr(e->param[0]) && verify_expr(e->param[1]);
}
}
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 (!isspace(*s++)) *wp++ = s[-1];
*wp++ = 0;
p.class = &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_expr_free(e);
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)) {
av_expr_free(e);
ret = AVERROR(EINVAL);
goto end;
}
e->var= av_mallocz(sizeof(double) *VARS);
*expr = e;
end:
av_free(w);
return ret;
}
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;
}
#if FF_API_OLD_EVAL_NAMES
// LCOV_EXCL_START
int av_parse_expr(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)
{
return av_expr_parse(expr, s, const_names, func1_names, funcs1, func2_names, funcs2,
log_offset, log_ctx);
}
double av_eval_expr(AVExpr *e, const double *const_values, void *opaque)
{
return av_expr_eval(e, const_values, opaque);
}
int av_parse_and_eval_expr(double *res, 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)
{
return av_expr_parse_and_eval(res, s, const_names, const_values, func1_names, funcs1, func2_names, funcs2,
opaque, log_offset, log_ctx);
}
void av_free_expr(AVExpr *e)
{
av_expr_free(e);
}
// LCOV_EXCL_STOP
#endif /* FF_API_OLD_EVAL_NAMES */
#ifdef TEST
// LCOV_EXCL_START
#undef printf
#include <string.h>
static double const_values[] = {
M_PI,
M_E,
0
};
static const char *const_names[] = {
"PI",
"E",
0
};
int main(int argc, char **argv)
{
int i;
double d;
const char **expr, *exprs[] = {
"",
"1;2",
"-20",
"-PI",
"+PI",
"1+(5-2)^(3-1)+1/2+sin(PI)-max(-2.2,-3.1)",
"80G/80Gi",
"1k",
"1Gi",
"1gi",
"1GiFoo",
"1k+1k",
"1Gi*3foo",
"foo",
"foo(",
"foo()",
"foo)",
"sin",
"sin(",
"sin()",
"sin)",
"sin 10",
"sin(1,2,3)",
"sin(1 )",
"1",
"1foo",
"bar + PI + E + 100f*2 + foo",
"13k + 12f - foo(1, 2)",
"1gi",
"1Gi",
"st(0, 123)",
"st(1, 123); ld(1)",
/* compute 1+2+...+N */
"st(0, 1); while(lte(ld(0), 100), st(1, ld(1)+ld(0));st(0, ld(0)+1)); ld(1)",
/* compute Fib(N) */
"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)",
"while(0, 10)",
"st(0, 1); while(lte(ld(0),100), st(1, ld(1)+ld(0)); st(0, ld(0)+1))",
"isnan(1)",
"isnan(NAN)",
"floor(NAN)",
"floor(123.123)",
"floor(-123.123)",
"trunc(123.123)",
"trunc(-123.123)",
"ceil(123.123)",
"ceil(-123.123)",
"sqrt(1764)",
"isnan(sqrt(-1))",
"not(1)",
"not(NAN)",
"not(0)",
"pow(0,1.23)",
"pow(PI,1.23)",
"PI^1.23",
"pow(-1,1.23)",
NULL
};
for (expr = exprs; *expr; expr++) {
printf("Evaluating '%s'\n", *expr);
av_expr_parse_and_eval(&d, *expr,
const_names, const_values,
NULL, NULL, NULL, NULL, NULL, 0, NULL);
if(isnan(d)){
printf("'%s' -> nan\n\n", *expr);
}else{
printf("'%s' -> %f\n\n", *expr, d);
}
}
av_expr_parse_and_eval(&d, "1+(5-2)^(3-1)+1/2+sin(PI)-max(-2.2,-3.1)",
const_names, const_values,
NULL, NULL, NULL, NULL, NULL, 0, NULL);
printf("%f == 12.7\n", d);
av_expr_parse_and_eval(&d, "80G/80Gi",
const_names, const_values,
NULL, NULL, NULL, NULL, NULL, 0, NULL);
printf("%f == 0.931322575\n", d);
if (argc > 1 && !strcmp(argv[1], "-t")) {
for (i = 0; i < 1050; i++) {
START_TIMER;
av_expr_parse_and_eval(&d, "1+(5-2)^(3-1)+1/2+sin(PI)-max(-2.2,-3.1)",
const_names, const_values,
NULL, NULL, NULL, NULL, NULL, 0, NULL);
STOP_TIMER("av_expr_parse_and_eval");
}
}
return 0;
}
// LCOV_EXCL_STOP
#endif