diff options
Diffstat (limited to 'tools/ffeval.c')
-rw-r--r-- | tools/ffeval.c | 139 |
1 files changed, 139 insertions, 0 deletions
diff --git a/tools/ffeval.c b/tools/ffeval.c new file mode 100644 index 0000000000..944f374727 --- /dev/null +++ b/tools/ffeval.c @@ -0,0 +1,139 @@ +/* + * 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 "config.h" +#if HAVE_UNISTD_H +#include <unistd.h> /* getopt */ +#endif + +#include "libavutil/eval.h" +#include "libavutil/mem.h" + +#if !HAVE_GETOPT +#include "compat/getopt.c" +#endif + +/** + * @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"); +} + +int main(int argc, char **argv) +{ + int buf_size = 0; + char *buf = NULL; + const char *outfilename = NULL, *infilename = NULL; + FILE *outfile = NULL, *infile = NULL; + const char *prompt = "=> "; + int count = 0, echo = 0; + int c; + +#define GROW_ARRAY() \ + do { \ + if (!av_dynarray2_add((void **)&buf, &buf_size, 1, NULL)) { \ + av_log(NULL, AV_LOG_ERROR, \ + "Memory allocation problem occurred\n"); \ + return 1; \ + } \ + } while (0) + + GROW_ARRAY(); + 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 = "stdin"; + infile = stdin; + } else { + 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 = "stdout"; + outfile = stdout; + } else { + 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] != '#') { + int ret = av_expr_parse_and_eval(&d, buf, + NULL, NULL, + NULL, NULL, NULL, NULL, NULL, 0, NULL); + if (echo) + fprintf(outfile, "%s ", buf); + if (ret >= 0) fprintf(outfile, "%s%f\n", prompt, d); + else fprintf(outfile, "%s%f (%s)\n", prompt, d, av_err2str(ret)); + } + count = 0; + } else { + if (count >= buf_size-1) + GROW_ARRAY(); + buf[count++] = c; + } + } + + av_free(buf); + return 0; +} |