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#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "as_tokenizer.h"
#include "as_op.h"
#include "utils.h"
int input_stream_next_char(struct input_stream * s) {
if (s->cursor == -1) {
return EOF;
}
if (s->buf_pos == s->cursor) {
size_t n = fread(s->buf, 1, INPUT_STREAM_BUF_SIZE, s->fp);
if (n == 0) {
s->cursor = -1;
return EOF;
}
s->buf_pos = n;
s->cursor = 0;
}
int c = s->buf[s->cursor];
s->cursor++;
if (c == '\n') {
s->line++;
s->col = 1;
} else {
s->col++;
}
return c;
}
int input_stream_peek_char(struct input_stream * s) {
if (s->cursor == -1) {
return EOF;
}
if (s->buf_pos == s->cursor) {
size_t n = fread(s->buf, 1, INPUT_STREAM_BUF_SIZE, s->fp);
if (n == 0) {
return EOF;
}
s->buf_pos = n;
s->cursor = 0;
}
return s->buf[s->cursor];
}
int is_start_of_identifier(int c) {
if (c >= 'a' && c <= 'z') {
return 1;
}
if (c >= 'A' && c <= 'Z') {
return 1;
}
if (c == '_') {
return 1;
}
if (c == '.') {
return 1;
}
return 0;
}
int is_part_of_identifier(int c) {
if (is_start_of_identifier(c)) {
return 1;
}
if (c >= '0' && c <= '9') {
return 1;
}
return 0;
}
struct result next_token_impl(struct allocator * alct, struct input_stream * s) {
const char *errmsg;
struct token * t = allocate(alct, sizeof(struct token));
int c;
while (1) {
c = input_stream_peek_char(s);
if (c == EOF) {
break;
}
if (c == '\n') {
input_stream_next_char(s);
*t = (struct token){.type = TK_NEWLINE, .line = s->line, .col = s->col};
return ok(t);
}
if (c == ':') {
input_stream_next_char(s);
*t = (struct token){.type = TK_COLON, .line = s->line, .col = s->col};
return ok(t);
}
if (c == ' ' || c == '\t') {
input_stream_next_char(s);
continue;
}
if (c >= '0' && c <= '9') {
int64_t ival = 0;
while (1) {
input_stream_next_char(s);
ival = ival * 10 + (c - '0');
c = input_stream_peek_char(s);
if (c < '0' || c > '9') {
break;
}
}
*t = (struct token){.type = TK_ARG, .ival = ival, .line = s->line, .col = s->col};
return ok(t);
}
if (is_start_of_identifier(c)) {
size_t line = s->line;
size_t col = s->col;
char *sval = allocate(alct, 256);
size_t i = 0;
while (1) {
if (i >= 255) {
return err(safe_sprintf(alct, "error: identifier too long\n"));
}
input_stream_next_char(s);
sval[i++] = c;
c = input_stream_peek_char(s);
if (!is_part_of_identifier(c)) {
break;
}
}
sval[i] = '\0';
if (isOp(sval)) {
*t = (struct token){.type = TK_OP, .sval = sval, .line = line, .col = col};
return ok(t);
}
*t = (struct token){.type = TK_TAG, .sval = sval, .line = line, .col = col};
return ok(t);
}
return err(safe_sprintf(alct, "error: invalid character %c at line %d, col %d\n", c, s->line, s->col));
}
// end of file
*t = (struct token){.type = TK_ENDOFFILE};
return ok(t);
}
struct result next_token(struct allocator * alct, struct token_stream * ts) {
if (ts->buf != NULL) {
struct token * t = ts->buf;
ts->buf = NULL;
return ok(t);
}
return next_token_impl(alct, ts->s);
}
struct result peek_token(struct allocator * alct, struct token_stream * ts) {
if (ts->buf != NULL) {
return ok(ts->buf);
}
ts->buf = unwrap(next_token_impl(alct, ts->s));
return ok(ts->buf);
}
void print_token(struct token * t) {
switch (t->type) {
case TK_OP:
printf("OP: %s, line: %d, col: %d\n", t->sval, t->line, t->col);
break;
case TK_ARG:
printf("ARG: %ld, line: %d, col: %d\n", t->ival, t->line, t->col);
break;
case TK_TAG:
printf("LABEL: %s, line: %d, col: %d\n", t->sval, t->line, t->col);
break;
case TK_COLON:
printf("COLON\n");
break;
case TK_NEWLINE:
printf("NEWLINE\n");
break;
case TK_ENDOFFILE:
printf("ENDOFFILE\n");
break;
}
}
struct token_stream * new_token_stream(struct allocator * alct, FILE* fp) {
struct input_stream * s = allocate(alct, sizeof(struct input_stream));
s->fp = fp;
s->buf = allocate(alct, INPUT_STREAM_BUF_SIZE);
s->buf_pos = 0;
s->cursor = 0;
s->line = 1;
s->col = 1;
struct token_stream * ts = allocate(alct, sizeof(struct token_stream));
ts->s = s;
ts->buf = NULL;
return ts;
}
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