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.
16 struct 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.
22 void 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.
27 int shgetc(struct fake_file_t *);
28 
29 // Back-track one character, must not be called more times than shgetc()
30 void 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.
36 void shlim(struct fake_file_t *, off_t lim);
37 
38 // Return the number of input characters that were read so far.
39 off_t shcnt(struct fake_file_t *);
40 
41 #endif  // SHGETC_H
42