OVMS3/OVMS.V3/components/console/split_argv.c

120 lines
3.6 KiB
C

// Copyright 2016-2017 Espressif Systems (Shanghai) PTE LTD
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#include <stdio.h>
#include <ctype.h>
#include <string.h>
#define SS_FLAG_ESCAPE 0x8
typedef enum {
/* parsing the space between arguments */
SS_SPACE = 0x0,
/* parsing an argument which isn't quoted */
SS_ARG = 0x1,
/* parsing a quoted argument */
SS_QUOTED_ARG = 0x2,
/* parsing an escape sequence within unquoted argument */
SS_ARG_ESCAPED = SS_ARG | SS_FLAG_ESCAPE,
/* parsing an escape sequence within a quoted argument */
SS_QUOTED_ARG_ESCAPED = SS_QUOTED_ARG | SS_FLAG_ESCAPE,
} split_state_t;
size_t esp_console_split_argv(char *line, char **argv, size_t argv_size)
{
const int QUOTE = '"';
const int ESCAPE = '\\';
const int SPACE = ' ';
split_state_t state = SS_SPACE;
int argc = 0;
char *next_arg_start = line;
char *out_ptr = line;
for (char *in_ptr = line; argc < argv_size - 1; ++in_ptr) {
int char_in = (unsigned char) *in_ptr;
if (char_in == 0) {
break;
}
int char_out = -1;
/* helper function, called when done with an argument */
void end_arg() {
char_out = 0;
argv[argc++] = next_arg_start;
state = SS_SPACE;
}
switch (state) {
case SS_SPACE:
if (char_in == SPACE) {
/* skip space */
} else if (char_in == QUOTE) {
next_arg_start = out_ptr;
state = SS_QUOTED_ARG;
} else if (char_in == ESCAPE) {
next_arg_start = out_ptr;
state = SS_ARG_ESCAPED;
} else {
next_arg_start = out_ptr;
state = SS_ARG;
char_out = char_in;
}
break;
case SS_QUOTED_ARG:
if (char_in == QUOTE) {
end_arg();
} else if (char_in == ESCAPE) {
state = SS_QUOTED_ARG_ESCAPED;
} else {
char_out = char_in;
}
break;
case SS_ARG_ESCAPED:
case SS_QUOTED_ARG_ESCAPED:
if (char_in == ESCAPE || char_in == QUOTE || char_in == SPACE) {
char_out = char_in;
} else {
/* unrecognized escape character, skip */
}
state = (split_state_t) (state & (~SS_FLAG_ESCAPE));
break;
case SS_ARG:
if (char_in == SPACE) {
end_arg();
} else if (char_in == ESCAPE) {
state = SS_ARG_ESCAPED;
} else {
char_out = char_in;
}
break;
}
/* need to output anything? */
if (char_out >= 0) {
*out_ptr = char_out;
++out_ptr;
}
}
/* make sure the final argument is terminated */
*out_ptr = 0;
/* finalize the last argument */
if (state != SS_SPACE && argc < argv_size - 1) {
argv[argc++] = next_arg_start;
}
/* add a NULL at the end of argv */
argv[argc] = NULL;
return argc;
}