tools/ffescape.c

   1 /*
   2  * Copyright (c) 2012 Stefano Sabatini
   3  *
   4  * This file is part of FFmpeg.
   5  *
   6  * FFmpeg is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2.1 of the License, or (at your option) any later version.
  10  *
  11  * FFmpeg is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public
  17  * License along with FFmpeg; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  19  */
  20
  21 #include "config.h"
  22 #include <errno.h>
  23 #include <limits.h>
  24 #include <stdio.h>
  25 #include <stdlib.h>
  26 #include <string.h>
  27 #if HAVE_UNISTD_H
  28 #include <unistd.h>             /* getopt */
  29 #endif
  30
  31 #include "libavutil/log.h"
  32 #include "libavutil/bprint.h"
  33 #include "libavutil/mem.h"
  34
  35 #if !HAVE_GETOPT
  36 #include "compat/getopt.c"
  37 #endif
  38
  39 /**
  40  * @file
  41  * escaping utility
  42  */
  43
  44 static void usage(void)
  45 {
  46     printf("Escape an input string, adopting the av_get_token() escaping logic\n");
  47     printf("usage: ffescape [OPTIONS]\n");
  48     printf("\n"
  49            "Options:\n"
  50            "-e                echo each input line on output\n"
  51            "-f flag           select an escape flag, can assume the values 'whitespace' and 'strict'\n"
  52            "-h                print this help\n"
  53            "-i INFILE         set INFILE as input file, stdin if omitted\n"
  54            "-l LEVEL          set the number of escaping levels, 1 if omitted\n"
  55            "-m ESCAPE_MODE    select escape mode between 'auto', 'backslash', 'quote'\n"
  56            "-o OUTFILE        set OUTFILE as output file, stdout if omitted\n"
  57            "-p PROMPT         set output prompt, is '=> ' by default\n"
  58            "-s SPECIAL_CHARS  set the list of special characters\n");
  59 }
  60
  61 int main(int argc, char **argv)
  62 {
  63     AVBPrint src;
  64     char *src_buf, *dst_buf;
  65     const char *outfilename = NULL, *infilename = NULL;
  66     FILE *outfile = NULL, *infile = NULL;
  67     const char *prompt = "=> ";
  68     enum AVEscapeMode escape_mode = AV_ESCAPE_MODE_AUTO;
  69     int escape_flags = 0;
  70     int level = 1;
  71     int echo = 0;
  72     char *special_chars = NULL;
  73     int c;
  74
  75     while ((c = getopt(argc, argv, "ef:hi:l:o:m:p:s:")) != -1) {
  76         switch (c) {
  77         case 'e':
  78             echo = 1;
  79             break;
  80         case 'h':
  81             usage();
  82             return 0;
  83         case 'i':
  84             infilename = optarg;
  85             break;
  86         case 'f':
  87             if      (!strcmp(optarg, "whitespace"))        escape_flags |= AV_ESCAPE_FLAG_WHITESPACE;
  88             else if (!strcmp(optarg, "strict"))            escape_flags |= AV_ESCAPE_FLAG_STRICT;
  89             else if (!strcmp(optarg, "xml_single_quotes")) escape_flags |= AV_ESCAPE_FLAG_XML_SINGLE_QUOTES;
  90             else if (!strcmp(optarg, "xml_double_quotes")) escape_flags |= AV_ESCAPE_FLAG_XML_DOUBLE_QUOTES;
  91             else {
  92                 av_log(NULL, AV_LOG_ERROR,
  93                        "Invalid value '%s' for option -f, "
  94                        "valid arguments are 'whitespace', and 'strict'\n", optarg);
  95                 return 1;
  96             }
  97             break;
  98         case 'l':
  99         {
 100             char *tail;
 101             long int li = strtol(optarg, &tail, 10);
 102             if (*tail || li > INT_MAX || li < 0) {
 103                 av_log(NULL, AV_LOG_ERROR,
 104                         "Invalid value '%s' for option -l, argument must be a non negative integer\n",
 105                         optarg);
 106                 return 1;
 107             }
 108             level = li;
 109             break;
 110         }
 111         case 'm':
 112             if      (!strcmp(optarg, "auto"))      escape_mode = AV_ESCAPE_MODE_AUTO;
 113             else if (!strcmp(optarg, "backslash")) escape_mode = AV_ESCAPE_MODE_BACKSLASH;
 114             else if (!strcmp(optarg, "quote"))     escape_mode = AV_ESCAPE_MODE_QUOTE;
 115             else if (!strcmp(optarg, "xml"))       escape_mode = AV_ESCAPE_MODE_XML;
 116             else {
 117                 av_log(NULL, AV_LOG_ERROR,
 118                        "Invalid value '%s' for option -m, "
 119                        "valid arguments are 'backslash', and 'quote'\n", optarg);
 120                 return 1;
 121             }
 122             break;
 123         case 'o':
 124             outfilename = optarg;
 125             break;
 126         case 'p':
 127             prompt = optarg;
 128             break;
 129         case 's':
 130             special_chars = optarg;
 131             break;
 132         case '?':
 133             return 1;
 134         }
 135     }
 136
 137     if (!infilename || !strcmp(infilename, "-")) {
 138         infilename = "stdin";
 139         infile = stdin;
 140     } else {
 141         infile = fopen(infilename, "r");
 142     }
 143     if (!infile) {
 144         av_log(NULL, AV_LOG_ERROR, "Impossible to open input file '%s': %s\n", infilename, strerror(errno));
 145         return 1;
 146     }
 147
 148     if (!outfilename || !strcmp(outfilename, "-")) {
 149         outfilename = "stdout";
 150         outfile = stdout;
 151     } else {
 152         outfile = fopen(outfilename, "w");
 153     }
 154     if (!outfile) {
 155         av_log(NULL, AV_LOG_ERROR, "Impossible to open output file '%s': %s\n", outfilename, strerror(errno));
 156         return 1;
 157     }
 158
 159     /* grab the input and store it in src */
 160     av_bprint_init(&src, 1, AV_BPRINT_SIZE_UNLIMITED);
 161     while ((c = fgetc(infile)) != EOF)
 162         av_bprint_chars(&src, c, 1);
 163     av_bprint_chars(&src, 0, 1);
 164
 165     if (!av_bprint_is_complete(&src)) {
 166         av_log(NULL, AV_LOG_ERROR, "Could not allocate a buffer for the source string\n");
 167         av_bprint_finalize(&src, NULL);
 168         return 1;
 169     }
 170     av_bprint_finalize(&src, &src_buf);
 171
 172     if (echo)
 173         fprintf(outfile, "%s", src_buf);
 174
 175     /* escape */
 176     dst_buf = src_buf;
 177     while (level--) {
 178         if (av_escape(&dst_buf, src_buf, special_chars, escape_mode, escape_flags) < 0) {
 179             av_log(NULL, AV_LOG_ERROR, "Could not escape string\n");
 180             return 1;
 181         }
 182         av_free(src_buf);
 183         src_buf = dst_buf;
 184     }
 185
 186     fprintf(outfile, "%s%s", prompt, dst_buf);
 187     av_free(dst_buf);
 188     return 0;
 189 }