From 15f52e50fe37bdc8778f3f6097ba343c871ec228 Mon Sep 17 00:00:00 2001 From: Stefano Sabatini Date: Mon, 15 Oct 2012 12:17:15 +0200 Subject: tools: add ffescape utility --- tools/ffescape.c | 233 +++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 233 insertions(+) create mode 100644 tools/ffescape.c (limited to 'tools/ffescape.c') diff --git a/tools/ffescape.c b/tools/ffescape.c new file mode 100644 index 0000000000..d777fe4572 --- /dev/null +++ b/tools/ffescape.c @@ -0,0 +1,233 @@ +/* + * 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 /* getopt */ +#endif + +#include "libavutil/log.h" +#include "libavutil/bprint.h" + +#if !HAVE_GETOPT +#include "compat/getopt.c" +#endif + +/** + * @file + * escaping utility + */ + +static void usage(void) +{ + printf("Escape an input string, adopting the av_get_token() escaping logic\n"); + printf("usage: ffescape [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" + "-l LEVEL set the number of escaping levels, 1 if omitted\n" + "-m ESCAPE_MODE select escape mode between 'full', 'lazy', 'quote', default is 'lazy'\n" + "-o OUTFILE set OUTFILE as output file, stdout if omitted\n" + "-p PROMPT set output prompt, is '=> ' by default\n" + "-s SPECIAL_CHARS set the list of special characters\n"); +} + +#define WHITESPACES " \n\t" + +enum EscapeMode { + ESCAPE_MODE_FULL, + ESCAPE_MODE_LAZY, + ESCAPE_MODE_QUOTE, +}; + +static int escape(char **dst, const char *src, const char *special_chars, + enum EscapeMode mode) +{ + AVBPrint dstbuf; + + av_bprint_init(&dstbuf, 1, AV_BPRINT_SIZE_UNLIMITED); + + switch (mode) { + case ESCAPE_MODE_FULL: + case ESCAPE_MODE_LAZY: + /* \-escape characters */ + + if (mode == ESCAPE_MODE_LAZY && strchr(WHITESPACES, *src)) + av_bprintf(&dstbuf, "\\%c", *src++); + + for (; *src; src++) { + if ((special_chars && strchr(special_chars, *src)) || + strchr("'\\", *src) || + (mode == ESCAPE_MODE_FULL && strchr(WHITESPACES, *src))) + av_bprintf(&dstbuf, "\\%c", *src); + else + av_bprint_chars(&dstbuf, *src, 1); + } + + if (mode == ESCAPE_MODE_LAZY && strchr(WHITESPACES, dstbuf.str[dstbuf.len-1])) { + char c = dstbuf.str[dstbuf.len-1]; + dstbuf.str[dstbuf.len-1] = '\\'; + av_bprint_chars(&dstbuf, c, 1); + } + break; + + case ESCAPE_MODE_QUOTE: + /* enclose between '' the string */ + av_bprint_chars(&dstbuf, '\'', 1); + for (; *src; src++) { + if (*src == '\'') + av_bprintf(&dstbuf, "'\\''"); + else + av_bprint_chars(&dstbuf, *src, 1); + } + av_bprint_chars(&dstbuf, '\'', 1); + break; + + default: + /* unknown escape mode */ + return AVERROR(EINVAL); + } + + if (!av_bprint_is_complete(&dstbuf)) { + av_bprint_finalize(&dstbuf, NULL); + return AVERROR(ENOMEM); + } else { + av_bprint_finalize(&dstbuf, dst); + return 0; + } +} + +int main(int argc, char **argv) +{ + AVBPrint src; + char *src_buf, *dst_buf; + const char *outfilename = NULL, *infilename = NULL; + FILE *outfile = NULL, *infile = NULL; + const char *prompt = "=> "; + enum EscapeMode escape_mode = ESCAPE_MODE_LAZY; + int level = 1; + int echo = 0; + char *special_chars = NULL; + int c; + + while ((c = getopt(argc, argv, "ehi:l:o:m:p:s:")) != -1) { + switch (c) { + case 'e': + echo = 1; + break; + case 'h': + usage(); + return 0; + case 'i': + infilename = optarg; + break; + case 'l': + { + char *tail; + long int li = strtol(optarg, &tail, 10); + if (*tail || li > INT_MAX || li < 0) { + av_log(NULL, AV_LOG_ERROR, + "Invalid value '%s' for option -l, argument must be a non negative integer\n", + optarg); + return 1; + } + level = li; + break; + } + case 'm': + if (!strcmp(optarg, "full")) escape_mode = ESCAPE_MODE_FULL; + else if (!strcmp(optarg, "lazy")) escape_mode = ESCAPE_MODE_LAZY; + else if (!strcmp(optarg, "quote")) escape_mode = ESCAPE_MODE_QUOTE; + else { + av_log(NULL, AV_LOG_ERROR, + "Invalid value '%s' for option -m, " + "valid arguments are 'full', 'lazy', 'quote'\n", optarg); + return 1; + } + break; + case 'o': + outfilename = optarg; + break; + case 'p': + prompt = optarg; + break; + case 's': + special_chars = optarg; + break; + case '?': + return 1; + } + } + + if (!infilename || !strcmp(infilename, "-")) { + infilename = "stdin"; + infile = stdin; + } else { + infile = fopen(infilename, "r"); + } + if (!infile) { + av_log(NULL, AV_LOG_ERROR, "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) { + av_log(NULL, AV_LOG_ERROR, "Impossible to open output file '%s': %s\n", outfilename, strerror(errno)); + return 1; + } + + /* grab the input and store it in src */ + av_bprint_init(&src, 1, AV_BPRINT_SIZE_UNLIMITED); + while ((c = fgetc(infile)) != EOF) + av_bprint_chars(&src, c, 1); + av_bprint_chars(&src, 0, 1); + + if (!av_bprint_is_complete(&src)) { + av_log(NULL, AV_LOG_ERROR, "Could not allocate a buffer for the source string\n"); + av_bprint_finalize(&src, NULL); + return 1; + } + av_bprint_finalize(&src, &src_buf); + + if (echo) + fprintf(outfile, "%s", src_buf); + + /* escape */ + dst_buf = src_buf; + while (level--) { + if (escape(&dst_buf, src_buf, special_chars, escape_mode) < 0) { + av_log(NULL, AV_LOG_ERROR, "Could not escape string\n"); + return 1; + } + av_free(src_buf); + src_buf = dst_buf; + } + + fprintf(outfile, "%s%s", prompt, dst_buf); + av_free(dst_buf); + return 0; +} -- cgit v1.2.3