5 * Permission is hereby granted, free of charge, to any person obtaining a copy of
6 * this software and associated documentation files (the "Software"), to deal in
7 * the Software without restriction, including without limitation the rights to
8 * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
9 * of the Software, and to permit persons to whom the Software is furnished to do
10 * so, subject to the following conditions:
12 * The above copyright notice and this permission notice shall be included in all
13 * copies or substantial portions of the Software.
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
18 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
20 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
30 static const char *const lex_keywords[] = {
31 "do", "else", "if", "while",
32 "break", "continue", "return", "goto",
45 struct lex_file *lex_open(FILE *fp) {
46 struct lex_file *lex = mem_a(sizeof(struct lex_file));
49 fseek(lex->file, 0, SEEK_END);
50 lex->length = ftell(lex->file);
51 lex->size = lex->length; /* copy, this is never changed */
52 fseek(lex->file, 0, SEEK_SET);
55 memset(lex->peek, 0, sizeof(lex->peek));
60 int lex_close(struct lex_file *file) {
63 ret = fclose(file->file);
69 static void lex_addch(int ch, struct lex_file *file) {
70 if (file->current < sizeof(file->lastok)-1)
71 file->lastok[file->current++] = (char)ch;
72 if (file->current == sizeof(file->lastok)-1)
73 file->lastok[file->current] = (char)'\0';
75 static inline void lex_clear(struct lex_file *file) {
80 * read in inget/unget character from a lexer stream.
81 * This doesn't play with file streams, the lexer has
82 * it's own internal state for this.
84 static int lex_inget(struct lex_file *file) {
87 return file->peek[--file->last];
88 return fgetc(file->file);
90 static void lex_unget(int ch, struct lex_file *file) {
91 if (file->last < sizeof(file->peek))
92 file->peek[file->last++] = ch;
97 * This is trigraph and digraph support, a feature not qc compiler
98 * supports. Moving up in this world!
100 static int lex_trigraph(struct lex_file *file) {
102 if ((ch = lex_inget(file)) != '?') {
107 ch = lex_inget(file);
109 case '(' : return '[' ;
110 case ')' : return ']' ;
111 case '/' : return '\\';
112 case '\'': return '^' ;
113 case '<' : return '{' ;
114 case '>' : return '}' ;
115 case '!' : return '|' ;
116 case '-' : return '~' ;
117 case '=' : return '#' ;
119 lex_unget('?', file);
120 lex_unget(ch , file);
125 static int lex_digraph(struct lex_file *file, int first) {
126 int ch = lex_inget(file);
129 if (ch == '%') return '{';
130 if (ch == ':') return '[';
133 if (ch == '>') return '}';
134 if (ch == ':') return '#';
137 if (ch == '>') return ']';
145 static int lex_getch(struct lex_file *file) {
146 int ch = lex_inget(file);
148 return lex_trigraph(file);
149 if (ch == '<' || ch == ':' || ch == '%')
150 return lex_digraph (file, ch);
155 static int lex_get(struct lex_file *file) {
157 if (!isspace(ch = lex_getch(file)))
160 /* skip over all spaces */
161 while (isspace(ch) && ch != '\n')
162 ch = lex_getch(file);
171 static int lex_skipchr(struct lex_file *file) {
176 lex_addch('\'', file);
178 for (it = 0; it < 2 && ((ch = lex_inget(file)) != '\''); it++) {
184 lex_addch(lex_getch(file), file);
186 lex_addch('\'', file);
187 lex_addch('\0', file);
195 static int lex_skipstr(struct lex_file *file) {
198 lex_addch('"', file);
200 while ((ch = lex_getch(file)) != '"') {
201 if (ch == '\n' || ch == EOF)
206 lex_addch(lex_inget(file), file);
209 lex_addch('"', file);
210 lex_addch('\0', file);
214 static int lex_skipcmt(struct lex_file *file) {
217 ch = lex_getch(file);
220 lex_addch('/', file);
221 lex_addch('/', file);
223 while ((ch = lex_getch(file)) != '\n') {
226 lex_addch(lex_getch(file), file);
231 lex_addch('\0', file);
240 lex_addch('/', file);
245 while ((ch = lex_getch(file)) != '*') {
247 return error(ERROR_LEX, "malformatted comment", " ");
252 } while ((ch = lex_getch(file)) != '/');
254 lex_addch('/', file);
255 lex_addch('\0', file);
260 static int lex_getsource(struct lex_file *file) {
261 int ch = lex_get(file);
263 /* skip char/string/comment */
265 case '\'': return lex_skipchr(file);
266 case '"': return lex_skipstr(file);
267 case '/': return lex_skipcmt(file);
272 int lex_token(struct lex_file *file) {
273 int ch = lex_getsource(file);
276 /* valid identifier */
277 if (ch > 0 && (ch == '_' || isalpha(ch))) {
279 while (ch > 0 && (isalpha(ch) || ch == '_')) {
281 ch = lex_getsource(file);
284 lex_addch('\0', file);
286 /* look inside the table for a keyword .. */
287 for (it = 0; it < sizeof(lex_keywords)/sizeof(*lex_keywords); it++)
288 if (!strncmp(file->lastok, lex_keywords[it], sizeof(lex_keywords[it])))
296 void lex_reset(struct lex_file *file) {
299 file->length = file->size;
300 fseek(file->file, 0, SEEK_SET);
302 memset(file->peek, 0, sizeof(file->peek ));
303 memset(file->lastok, 0, sizeof(file->lastok));
306 int lex_debug(struct lex_file *file) {
312 int list_continue = 0;
317 printf("===========================\nTOKENS: \n===========================\n");
318 while ((token = lex_token(file)) != ERROR_LEX && file->length >= 0) {
321 case 0: list_do ++; break;
322 case 1: list_else ++; break;
323 case 2: list_if ++; break;
324 case 3: list_while ++; break;
325 case 4: list_break ++; break;
326 case 5: list_continue++; break;
327 case 6: list_return ++; break;
328 case 7: list_goto ++; break;
329 case 8: list_for ++; break;
332 if (token >= 33 && token <= 126)
335 printf("\n===========================\nBRANCHES \n===========================\n");
336 printf("\t if % 8d\n", list_if);
337 printf("\t else % 8d\n", list_else);
338 printf("===========================\nLOOPS \n===========================\n");
339 printf("\t for % 8d\n", list_for);
340 printf("\t while % 8d\n", list_while);
341 printf("\t do % 8d\n", list_do);
342 printf("===========================\nSTATEMENTS \n===========================\n");
343 printf("\t break % 8d\n", list_break);
344 printf("\t continue % 8d\n", list_continue);
345 printf("\t return % 8d\n", list_return);
346 printf("\t goto % 8d\n", list_goto);
347 printf("===========================\nIDENTIFIERS\n===========================\n");
349 while ((token = lex_token(file)) != ERROR_LEX && file->length >= 0)
350 if (token == LEX_IDENT)
351 printf("%s ", file->lastok);