mirror of
https://git.videolan.org/git/ffmpeg.git
synced 2024-08-31 21:46:38 +02:00
![Stefano Sabatini](/assets/img/avatar_default.png)
The tool is useful for testing the internal arithmetic evaluation engine (indeed I plan to use it in FATE), and provides a handy calculator when you can't rely on bc ;-).
129 lines
3.9 KiB
C
129 lines
3.9 KiB
C
/*
|
|
* Copyright (c) 2012 Stefano Sabatini
|
|
*
|
|
* 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
|
|
*/
|
|
|
|
#include <unistd.h> /* getopt */
|
|
#include "libavutil/eval.h"
|
|
|
|
/**
|
|
* @file
|
|
* simple arithmetic expression evaluator
|
|
*/
|
|
|
|
static void usage(void)
|
|
{
|
|
printf("Simple expression evalutor, please *don't* turn me to a feature-complete language interpreter\n");
|
|
printf("usage: ffeval [OPTIONS]\n");
|
|
printf("\n"
|
|
"Options:\n"
|
|
"-e echo each input line on output\n"
|
|
"-h print this help\n"
|
|
"-i INFILE set INFILE as input file, stdin if omitted\n"
|
|
"-o OUTFILE set OUTFILE as output file, stdout if omitted\n"
|
|
"-p PROMPT set output prompt\n");
|
|
}
|
|
|
|
#define MAX_BLOCK_SIZE SIZE_MAX
|
|
|
|
int main(int argc, char **argv)
|
|
{
|
|
size_t buf_size = 256;
|
|
char *buf = av_malloc(buf_size);
|
|
const char *outfilename = NULL, *infilename = NULL;
|
|
FILE *outfile = NULL, *infile = NULL;
|
|
const char *prompt = "=> ";
|
|
int count = 0, echo = 0;
|
|
char c;
|
|
|
|
av_max_alloc(MAX_BLOCK_SIZE);
|
|
|
|
while ((c = getopt(argc, argv, "ehi:o:p:")) != -1) {
|
|
switch (c) {
|
|
case 'e':
|
|
echo = 1;
|
|
break;
|
|
case 'h':
|
|
usage();
|
|
return 0;
|
|
case 'i':
|
|
infilename = optarg;
|
|
break;
|
|
case 'o':
|
|
outfilename = optarg;
|
|
break;
|
|
case 'p':
|
|
prompt = optarg;
|
|
break;
|
|
case '?':
|
|
return 1;
|
|
}
|
|
}
|
|
|
|
if (!infilename || !strcmp(infilename, "-"))
|
|
infilename = "/dev/stdin";
|
|
infile = fopen(infilename, "r");
|
|
if (!infile) {
|
|
fprintf(stderr, "Impossible to open input file '%s': %s\n", infilename, strerror(errno));
|
|
return 1;
|
|
}
|
|
|
|
if (!outfilename || !strcmp(outfilename, "-"))
|
|
outfilename = "/dev/stdout";
|
|
outfile = fopen(outfilename, "w");
|
|
if (!outfile) {
|
|
fprintf(stderr, "Impossible to open output file '%s': %s\n", outfilename, strerror(errno));
|
|
return 1;
|
|
}
|
|
|
|
while ((c = fgetc(infile)) != EOF) {
|
|
if (c == '\n') {
|
|
double d;
|
|
|
|
buf[count] = 0;
|
|
if (buf[0] != '#') {
|
|
av_expr_parse_and_eval(&d, buf,
|
|
NULL, NULL,
|
|
NULL, NULL, NULL, NULL, NULL, 0, NULL);
|
|
if (echo)
|
|
fprintf(outfile, "%s ", buf);
|
|
fprintf(outfile, "%s%f\n", prompt, d);
|
|
}
|
|
count = 0;
|
|
} else {
|
|
if (count >= buf_size-1) {
|
|
if (buf_size == MAX_BLOCK_SIZE) {
|
|
av_log(NULL, AV_LOG_ERROR, "Memory allocation problem, "
|
|
"max block size '%zd' reached\n", MAX_BLOCK_SIZE);
|
|
return 1;
|
|
}
|
|
buf_size = FFMIN(buf_size, MAX_BLOCK_SIZE / 2) * 2;
|
|
buf = av_realloc_f((void *)buf, buf_size, 1);
|
|
if (!buf) {
|
|
av_log(NULL, AV_LOG_ERROR, "Memory allocation problem occurred\n");
|
|
return 1;
|
|
}
|
|
}
|
|
buf[count++] = c;
|
|
}
|
|
}
|
|
|
|
av_free(buf);
|
|
return 0;
|
|
}
|