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/*
* Copyright (C) 2003-2009 The Music Player Daemon Project
* http://www.musicpd.org
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#include "tokenizer.h"
#include <stdbool.h>
#include <assert.h>
#include <string.h>
G_GNUC_CONST
static GQuark
tokenizer_quark(void)
{
return g_quark_from_static_string("tokenizer");
}
static inline bool
valid_word_first_char(char ch)
{
return g_ascii_isalpha(ch);
}
static inline bool
valid_word_char(char ch)
{
return g_ascii_isalnum(ch) || ch == '_';
}
char *
tokenizer_next_word(char **input_p, GError **error_r)
{
char *word, *input;
assert(input_p != NULL);
assert(*input_p != NULL);
word = input = *input_p;
if (*input == 0)
return NULL;
/* check the first character */
if (!valid_word_first_char(*input)) {
g_set_error(error_r, tokenizer_quark(), 0,
"Letter expected");
return NULL;
}
/* now iterate over the other characters until we find a
whitespace or end-of-string */
while (*++input != 0) {
if (g_ascii_isspace(*input)) {
/* a whitespace: the word ends here */
*input = 0;
/* skip all following spaces, too */
input = g_strchug(input + 1);
break;
}
if (!valid_word_char(*input)) {
*input_p = input;
g_set_error(error_r, tokenizer_quark(), 0,
"Invalid word character");
return NULL;
}
}
/* end of string: the string is already null-terminated
here */
*input_p = input;
return word;
}
char *
tokenizer_next_string(char **input_p, GError **error_r)
{
char *word, *dest, *input;
assert(input_p != NULL);
assert(*input_p != NULL);
word = dest = input = *input_p;
if (*input == 0)
/* end of line */
return NULL;
/* check for the opening " */
if (*input != '"') {
g_set_error(error_r, tokenizer_quark(), 0,
"'\"' expected");
return NULL;
}
++input;
/* copy all characters */
while (*input != '"') {
if (*input == '\\')
/* the backslash escapes the following
character */
++input;
if (*input == 0) {
/* return input-1 so the caller can see the
difference between "end of line" and
"error" */
*input_p = input - 1;
g_set_error(error_r, tokenizer_quark(), 0,
"Missing closing '\"'");
return NULL;
}
/* copy one character */
*dest++ = *input++;
}
/* the following character must be a whitespace (or end of
line) */
++input;
if (*input != 0 && !g_ascii_isspace(*input)) {
*input_p = input;
g_set_error(error_r, tokenizer_quark(), 0,
"Space expected after closing '\"'");
return NULL;
}
/* finish the string and return it */
*dest = 0;
*input_p = g_strchug(input);
return word;
}
char *
tokenizer_next_word_or_string(char **input_p, GError **error_r)
{
assert(input_p != NULL);
assert(*input_p != NULL);
if (**input_p == '"')
return tokenizer_next_string(input_p, error_r);
else
return tokenizer_next_word(input_p, error_r);
}
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