yading@11: /*
yading@11:  * Copyright (c) 2012 Stefano Sabatini
yading@11:  *
yading@11:  * This file is part of FFmpeg.
yading@11:  *
yading@11:  * FFmpeg is free software; you can redistribute it and/or
yading@11:  * modify it under the terms of the GNU Lesser General Public
yading@11:  * License as published by the Free Software Foundation; either
yading@11:  * version 2.1 of the License, or (at your option) any later version.
yading@11:  *
yading@11:  * FFmpeg is distributed in the hope that it will be useful,
yading@11:  * but WITHOUT ANY WARRANTY; without even the implied warranty of
yading@11:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
yading@11:  * Lesser General Public License for more details.
yading@11:  *
yading@11:  * You should have received a copy of the GNU Lesser General Public
yading@11:  * License along with FFmpeg; if not, write to the Free Software
yading@11:  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
yading@11:  */
yading@11: 
yading@11: #include "config.h"
yading@11: #if HAVE_UNISTD_H
yading@11: #include <unistd.h>             /* getopt */
yading@11: #endif
yading@11: 
yading@11: #include "libavutil/eval.h"
yading@11: 
yading@11: #if !HAVE_GETOPT
yading@11: #include "compat/getopt.c"
yading@11: #endif
yading@11: 
yading@11: /**
yading@11:  * @file
yading@11:  * simple arithmetic expression evaluator
yading@11:  */
yading@11: 
yading@11: static void usage(void)
yading@11: {
yading@11:     printf("Simple expression evalutor, please *don't* turn me to a feature-complete language interpreter\n");
yading@11:     printf("usage: ffeval [OPTIONS]\n");
yading@11:     printf("\n"
yading@11:            "Options:\n"
yading@11:            "-e                echo each input line on output\n"
yading@11:            "-h                print this help\n"
yading@11:            "-i INFILE         set INFILE as input file, stdin if omitted\n"
yading@11:            "-o OUTFILE        set OUTFILE as output file, stdout if omitted\n"
yading@11:            "-p PROMPT         set output prompt\n");
yading@11: }
yading@11: 
yading@11: #define MAX_BLOCK_SIZE SIZE_MAX
yading@11: 
yading@11: int main(int argc, char **argv)
yading@11: {
yading@11:     size_t buf_size = 256;
yading@11:     char *buf = av_malloc(buf_size);
yading@11:     const char *outfilename = NULL, *infilename = NULL;
yading@11:     FILE *outfile = NULL, *infile = NULL;
yading@11:     const char *prompt = "=> ";
yading@11:     int count = 0, echo = 0;
yading@11:     int c;
yading@11: 
yading@11:     av_max_alloc(MAX_BLOCK_SIZE);
yading@11: 
yading@11:     while ((c = getopt(argc, argv, "ehi:o:p:")) != -1) {
yading@11:         switch (c) {
yading@11:         case 'e':
yading@11:             echo = 1;
yading@11:             break;
yading@11:         case 'h':
yading@11:             usage();
yading@11:             return 0;
yading@11:         case 'i':
yading@11:             infilename = optarg;
yading@11:             break;
yading@11:         case 'o':
yading@11:             outfilename = optarg;
yading@11:             break;
yading@11:         case 'p':
yading@11:             prompt = optarg;
yading@11:             break;
yading@11:         case '?':
yading@11:             return 1;
yading@11:         }
yading@11:     }
yading@11: 
yading@11:     if (!infilename || !strcmp(infilename, "-")) {
yading@11:         infilename = "stdin";
yading@11:         infile = stdin;
yading@11:     } else {
yading@11:         infile = fopen(infilename, "r");
yading@11:     }
yading@11:     if (!infile) {
yading@11:         fprintf(stderr, "Impossible to open input file '%s': %s\n", infilename, strerror(errno));
yading@11:         return 1;
yading@11:     }
yading@11: 
yading@11:     if (!outfilename || !strcmp(outfilename, "-")) {
yading@11:         outfilename = "stdout";
yading@11:         outfile = stdout;
yading@11:     } else {
yading@11:         outfile = fopen(outfilename, "w");
yading@11:     }
yading@11:     if (!outfile) {
yading@11:         fprintf(stderr, "Impossible to open output file '%s': %s\n", outfilename, strerror(errno));
yading@11:         return 1;
yading@11:     }
yading@11: 
yading@11:     while ((c = fgetc(infile)) != EOF) {
yading@11:         if (c == '\n') {
yading@11:             double d;
yading@11: 
yading@11:             buf[count] = 0;
yading@11:             if (buf[0] != '#') {
yading@11:                 av_expr_parse_and_eval(&d, buf,
yading@11:                                        NULL, NULL,
yading@11:                                        NULL, NULL, NULL, NULL, NULL, 0, NULL);
yading@11:                 if (echo)
yading@11:                     fprintf(outfile, "%s ", buf);
yading@11:                 fprintf(outfile, "%s%f\n", prompt, d);
yading@11:             }
yading@11:             count = 0;
yading@11:         } else {
yading@11:             if (count >= buf_size-1) {
yading@11:                 if (buf_size == MAX_BLOCK_SIZE) {
yading@11:                     av_log(NULL, AV_LOG_ERROR, "Memory allocation problem, "
yading@11:                            "max block size '%zd' reached\n", MAX_BLOCK_SIZE);
yading@11:                     return 1;
yading@11:                 }
yading@11:                 buf_size = FFMIN(buf_size, MAX_BLOCK_SIZE / 2) * 2;
yading@11:                 buf = av_realloc_f((void *)buf, buf_size, 1);
yading@11:                 if (!buf) {
yading@11:                     av_log(NULL, AV_LOG_ERROR, "Memory allocation problem occurred\n");
yading@11:                     return 1;
yading@11:                 }
yading@11:             }
yading@11:             buf[count++] = c;
yading@11:         }
yading@11:     }
yading@11: 
yading@11:     av_free(buf);
yading@11:     return 0;
yading@11: }