1#ifndef SHGETC_H
2#define SHGETC_H
3
4#include <stdio.h>
5#include <wchar.h>
6
7// Custom stream abstraction, replaces the Musl FILE type for
8// the purpose of scanning integers and floating points.
9// |rstart| is the start of the input string.
10// |rend| is the first wchar_t after it.
11// |rpos| is the current reading position.
12// |extra_eof| is a counter of positions past EOF. Needed because the
13// scanning routines more or less assume an infinite input string, with
14// EOF being returned when shgetc() is being called past the real end
15// of the input stream.
16struct fake_file_t {
17    const wchar_t *rstart, *rpos, *rend;
18    int extra_eof;
19};
20
21// Initialize fake_file_t structure from a wide-char string.
22void shinit_wcstring(struct fake_file_t *, const wchar_t *wcs);
23
24// Get next character from string. This convers the wide character to
25// an 8-bit value, which will be '@' in case of overflow. Returns EOF (-1)
26// in case of end-of-string.
27int shgetc(struct fake_file_t *);
28
29// Back-track one character, must not be called more times than shgetc()
30void shunget(struct fake_file_t *);
31
32// This will be called with a value of 0 for |lim| to force rewinding
33// to the start of the string. In Musl, this is also used in different
34// parts of the library to impose a local limit on the number of characters
35// that can be retrieved through shgetc(), but this is not necessary here.
36void shlim(struct fake_file_t *, off_t lim);
37
38// Return the number of input characters that were read so far.
39off_t shcnt(struct fake_file_t *);
40
41#endif  // SHGETC_H
42