/*
* 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/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;
}