diff options
Diffstat (limited to 'src/multibyte/mbrtowc.c')
-rw-r--r-- | src/multibyte/mbrtowc.c | 58 |
1 files changed, 58 insertions, 0 deletions
diff --git a/src/multibyte/mbrtowc.c b/src/multibyte/mbrtowc.c new file mode 100644 index 0000000..09badeb --- /dev/null +++ b/src/multibyte/mbrtowc.c @@ -0,0 +1,58 @@ +/* + * This code was written by Rich Felker in 2010; no copyright is claimed. + * This code is in the public domain. Attribution is appreciated but + * unnecessary. + */ + +#include <stdlib.h> +#include <inttypes.h> +#include <wchar.h> +#include <errno.h> + +#include "internal.h" + +size_t mbrtowc(wchar_t *wc, const char *src, size_t n, mbstate_t *st) +{ + static unsigned internal_state; + unsigned c; + const unsigned char *s = src; + const unsigned N = n; + + if (!st) st = (void *)&internal_state; + c = *(unsigned *)st; + + if (!s) { + s = ""; + wc = (void *)&wc; + n = 1; + } else if (!wc) wc = (void *)&wc; + + if (!n) return -2; + if (!c) { + if ((unsigned)*s < 0x80) return !!(*wc = *s); + if ((unsigned)*s-SA > SB-SA) goto ilseq; + c = bittab[*s++-SA]; n--; + } + + if (n) { + if (OOB(c,*s)) goto ilseq; +loop: + c = c<<6 | *s++-0x80; n--; + if (!(c&(1U<<31))) { + *(unsigned *)st = 0; + *wc = c; + return N-n; + } + if (n) { + if ((unsigned)*s-0x80 >= 0x40) goto ilseq; + goto loop; + } + } + + *(unsigned *)st = c; + return -2; +ilseq: + *(unsigned *)st = FAILSTATE; + errno = EILSEQ; + return -1; +} |