source: mainline/uspace/app/bdsh/tok.c@ 1edd6d0

lfn serial ticket/834-toolchain-update topic/msim-upgrade topic/simplify-dev-export
Last change on this file since 1edd6d0 was 7c3fb9b, checked in by Jiri Svoboda <jiri@…>, 7 years ago

Fix block comment formatting (ccheck).
  • Property mode set to 100644
File size: 7.3 KB
Line 
1/*
2 * Copyright (c) 2011 Martin Sucha
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 *
9 * - Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * - Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 * - The name of the author may not be used to endorse or promote products
15 * derived from this software without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 */
28
29#include <str.h>
30#include <assert.h>
31#include <stdlib.h>
32#include <stddef.h>
33#include <errno.h>
34
35#include "tok.h"
36
37/* Forward declarations of static functions */
38static wchar_t tok_get_char(tokenizer_t *);
39static wchar_t tok_look_char(tokenizer_t *);
40static errno_t tok_push_char(tokenizer_t *, wchar_t);
41static errno_t tok_push_token(tokenizer_t *);
42static bool tok_pending_chars(tokenizer_t *);
43static errno_t tok_finish_string(tokenizer_t *);
44static void tok_start_token(tokenizer_t *, token_type_t);
45
46/** Initialize the token parser
47 *
48 * @param tok the tokenizer structure to initialize
49 * @param input the input string to tokenize
50 * @param out_tokens array of strings where to store the result
51 * @param max_tokens number of elements of the out_tokens array
52 */
53errno_t tok_init(tokenizer_t *tok, char *input, token_t *out_tokens,
54 size_t max_tokens)
55{
56 tok->in = input;
57 tok->in_offset = 0;
58 tok->last_in_offset = 0;
59 tok->in_char_offset = 0;
60 tok->last_in_char_offset = 0;
61
62 tok->outtok = out_tokens;
63 tok->outtok_offset = 0;
64 tok->outtok_size = max_tokens;
65
66 /* Prepare a buffer where all the token strings will be stored */
67 size_t len = str_size(input) + max_tokens + 1;
68 char *tmp = malloc(len);
69
70 if (tmp == NULL) {
71 return ENOMEM;
72 }
73
74 tok->outbuf = tmp;
75 tok->outbuf_offset = 0;
76 tok->outbuf_size = len;
77 tok->outbuf_last_start = 0;
78
79 return EOK;
80}
81
82/** Finalize the token parser */
83void tok_fini(tokenizer_t *tok)
84{
85 if (tok->outbuf != NULL) {
86 free(tok->outbuf);
87 }
88}
89
90/** Tokenize the input string into the tokens */
91errno_t tok_tokenize(tokenizer_t *tok, size_t *tokens_length)
92{
93 errno_t rc;
94 wchar_t next_char;
95
96 /* Read the input line char by char and append tokens */
97 while ((next_char = tok_look_char(tok)) != 0) {
98 if (next_char == ' ') {
99 /*
100 * Push the token if there is any.
101 * There may not be any pending char for a token in case
102 * there are several spaces in the input.
103 */
104 if (tok_pending_chars(tok)) {
105 rc = tok_push_token(tok);
106 if (rc != EOK) {
107 return rc;
108 }
109 }
110 tok_start_token(tok, TOKTYPE_SPACE);
111 /* Eat all the spaces */
112 while (tok_look_char(tok) == ' ') {
113 tok_push_char(tok, tok_get_char(tok));
114 }
115 tok_push_token(tok);
116
117 } else if (next_char == '|') {
118 /*
119 * Pipes are tokens that are delimiters and should be
120 * output as a separate token
121 */
122 if (tok_pending_chars(tok)) {
123 rc = tok_push_token(tok);
124 if (rc != EOK) {
125 return rc;
126 }
127 }
128
129 tok_start_token(tok, TOKTYPE_PIPE);
130
131 rc = tok_push_char(tok, tok_get_char(tok));
132 if (rc != EOK) {
133 return rc;
134 }
135
136 rc = tok_push_token(tok);
137 if (rc != EOK) {
138 return rc;
139 }
140 } else if (next_char == '\'') {
141 /*
142 * A string starts with a quote (') and ends again with a quote.
143 * A literal quote is written as ''
144 */
145 tok_start_token(tok, TOKTYPE_TEXT);
146 /* Eat the quote */
147 tok_get_char(tok);
148 rc = tok_finish_string(tok);
149 if (rc != EOK) {
150 return rc;
151 }
152 } else {
153 if (!tok_pending_chars(tok)) {
154 tok_start_token(tok, TOKTYPE_TEXT);
155 }
156 /*
157 * If we are handling any other character, just append it to
158 * the current token.
159 */
160 rc = tok_push_char(tok, tok_get_char(tok));
161 if (rc != EOK) {
162 return rc;
163 }
164 }
165 }
166
167 /* Push the last token */
168 if (tok_pending_chars(tok)) {
169 rc = tok_push_token(tok);
170 if (rc != EOK) {
171 return rc;
172 }
173 }
174
175 *tokens_length = tok->outtok_offset;
176
177 return EOK;
178}
179
180/** Finish tokenizing an opened string */
181errno_t tok_finish_string(tokenizer_t *tok)
182{
183 errno_t rc;
184 wchar_t next_char;
185
186 while ((next_char = tok_look_char(tok)) != 0) {
187 if (next_char == '\'') {
188 /* Eat the quote */
189 tok_get_char(tok);
190 if (tok_look_char(tok) == '\'') {
191 /* Encode a single literal quote */
192 rc = tok_push_char(tok, '\'');
193 if (rc != EOK) {
194 return rc;
195 }
196
197 /* Swallow the additional one in the input */
198 tok_get_char(tok);
199 } else {
200 /* The string end */
201 return tok_push_token(tok);
202 }
203 } else {
204 rc = tok_push_char(tok, tok_get_char(tok));
205 if (rc != EOK) {
206 return rc;
207 }
208 }
209 }
210
211 /* If we are here, the string run to the end without being closed */
212 return EINVAL;
213}
214
215/** Get a char from input, advancing the input position */
216wchar_t tok_get_char(tokenizer_t *tok)
217{
218 tok->in_char_offset++;
219 return str_decode(tok->in, &tok->in_offset, STR_NO_LIMIT);
220}
221
222/** Get a char from input, while staying on the same input position */
223wchar_t tok_look_char(tokenizer_t *tok)
224{
225 size_t old_offset = tok->in_offset;
226 size_t old_char_offset = tok->in_char_offset;
227 wchar_t ret = tok_get_char(tok);
228 tok->in_offset = old_offset;
229 tok->in_char_offset = old_char_offset;
230 return ret;
231}
232
233/** Append a char to the end of the current token */
234errno_t tok_push_char(tokenizer_t *tok, wchar_t ch)
235{
236 return chr_encode(ch, tok->outbuf, &tok->outbuf_offset, tok->outbuf_size);
237}
238
239void tok_start_token(tokenizer_t *tok, token_type_t type)
240{
241 tok->current_type = type;
242}
243
244/** Push the current token to the output array */
245errno_t tok_push_token(tokenizer_t *tok)
246{
247 if (tok->outtok_offset >= tok->outtok_size) {
248 return EOVERFLOW;
249 }
250
251 if (tok->outbuf_offset >= tok->outbuf_size) {
252 return EOVERFLOW;
253 }
254
255 tok->outbuf[tok->outbuf_offset++] = 0;
256 token_t *tokinfo = &tok->outtok[tok->outtok_offset++];
257 tokinfo->type = tok->current_type;
258 tokinfo->text = tok->outbuf + tok->outbuf_last_start;
259 tokinfo->byte_start = tok->last_in_offset;
260 tokinfo->byte_length = tok->in_offset - tok->last_in_offset;
261 tokinfo->char_start = tok->last_in_char_offset;
262 tokinfo->char_length = tok->in_char_offset - tok->last_in_char_offset;
263 tok->outbuf_last_start = tok->outbuf_offset;
264
265 /* We have consumed the first char of the next token already */
266 tok->last_in_offset = tok->in_offset;
267 tok->last_in_char_offset = tok->in_char_offset;
268
269 return EOK;
270}
271
272/** Return true, if the current token is not empty */
273bool tok_pending_chars(tokenizer_t *tok)
274{
275 assert(tok->outbuf_offset >= tok->outbuf_last_start);
276 return (tok->outbuf_offset != tok->outbuf_last_start);
277}
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