119 lines
2.7 KiB
C++
119 lines
2.7 KiB
C++
#include "parser.h"
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int next_token(struct parse_state *state)
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{
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char *x = state->ptr;
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char *s;
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if (state->nexttoken) {
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int t = state->nexttoken;
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state->nexttoken = 0;
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return t;
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}
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for (;;) {
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switch (*x) {
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case 0:
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state->ptr = x;
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return T_EOF;
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case '\n':
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x++;
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state->ptr = x;
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return T_NEWLINE;
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case ' ':
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case '\t':
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case '\r':
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x++;
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continue;
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case '#':
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while (*x && (*x != '\n')) x++;
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if (*x == '\n') {
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state->ptr = x+1;
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return T_NEWLINE;
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} else {
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state->ptr = x;
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return T_EOF;
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}
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default:
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goto text;
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}
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}
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textdone:
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state->ptr = x;
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*s = 0;
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return T_TEXT;
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text:
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state->text = s = x;
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textresume:
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for (;;) {
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switch (*x) {
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case 0:
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goto textdone;
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case ' ':
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case '\t':
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case '\r':
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x++;
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goto textdone;
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case '\n':
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state->nexttoken = T_NEWLINE;
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x++;
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goto textdone;
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case '"':
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x++;
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for (;;) {
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switch (*x) {
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case 0:
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/* unterminated quoted thing */
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state->ptr = x;
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return T_EOF;
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case '"':
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x++;
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goto textresume;
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default:
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*s++ = *x++;
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}
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}
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break;
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case '\\':
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x++;
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switch (*x) {
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case 0:
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goto textdone;
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case 'n':
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*s++ = '\n';
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break;
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case 'r':
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*s++ = '\r';
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break;
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case 't':
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*s++ = '\t';
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break;
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case '\\':
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*s++ = '\\';
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break;
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case '\r':
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/* \ <cr> <lf> -> line continuation */
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if (x[1] != '\n') {
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x++;
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continue;
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}
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case '\n':
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/* \ <lf> -> line continuation */
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state->line++;
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x++;
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/* eat any extra whitespace */
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while((*x == ' ') || (*x == '\t')) x++;
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continue;
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default:
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/* unknown escape -- just copy */
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*s++ = *x++;
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}
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continue;
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default:
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*s++ = *x++;
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}
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}
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return T_EOF;
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}
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