ref: 433b9cd26eb5d27977eb8cde6bb1c019606e0ffa
dir: /src/libc/stdio/vfprintf.c/
#include <ctype.h> #include <limits.h> #include <stdarg.h> #include <stdint.h> #include <stdio.h> #include <string.h> #include <wchar.h> #define MAXPREC 50 #undef vfprintf enum { LONG = 1 << 0, LLONG = 1 << 1, SHORT = 1 << 2, CHAR = 1 << 3, SIZET = 1 << 4, PTRDIFF = 1 << 5, INTMAX = 1 << 6, VOIDPTR = 1 << 7, UNSIGNED = 1 << 8, ALTFORM = 1 << 9, }; struct conv { int sign; int prec; char *digs; int base; }; static uintmax_t getnum(va_list *va, int flags, int *sign) { uintmax_t uval; intmax_t val; if (flags & CHAR) { val = va_arg(*va, int); uval = (unsigned char) val; } else if (flags & SHORT) { val = va_arg(*va, int); uval = (unsigned short) val; } else if (flags & LONG) { val = va_arg(*va, long); uval = (unsigned long) val; } else if (flags & LLONG) { val = va_arg(*va, long long); uval = (unsigned long long) val; } else if (flags & SIZET) { uval = va_arg(*va, size_t); } else if (flags & INTMAX) { val = va_arg(*va, intmax_t); uval = (uintmax_t) val; } else if (flags & VOIDPTR) { uval = (uintmax_t) va_arg(*va, void *); } else { val = va_arg(*va, int); uval = (unsigned) val; } if ((flags & UNSIGNED) == 0 && val < 0) { *sign = '-'; uval = -val; } return uval; } static char * numtostr(uintmax_t val, int flags, struct conv *conv, char *buf) { char *buf0 = buf; int base = conv->base, prec = conv->prec; uintmax_t oval = val; if (prec == -1) prec = 1; for (*buf = '\0'; val > 0; val /= base) *--buf = conv->digs[val % base]; while (buf0 - buf < prec) *--buf = '0'; if (flags & ALTFORM) { if (base == 8 && *buf != '0') { *--buf = '0'; } else if (base == 16 && oval != 0) { *--buf = conv->digs[16]; *--buf = '0'; } } if (conv->sign) *--buf = conv->sign; return buf; } static void savecnt(va_list *va, int flags, int cnt) { if (flags & CHAR) *va_arg(*va, char*) = cnt; else if (flags & SHORT) *va_arg(*va, short*) = cnt; else if (flags & LONG) *va_arg(*va, long*) = cnt; else if (flags & LLONG) *va_arg(*va, long long*) = cnt; else if (flags & SIZET) *va_arg(*va, size_t*) = cnt; else if (flags & INTMAX) *va_arg(*va, intmax_t*) = cnt; else *va_arg(*va, int*) = cnt; } static size_t wstrout(wchar_t *ws, size_t len, int width, int fill, FILE * restrict fp) { int left = 0, adjust; size_t cnt = 0; wchar_t wc; #if 0 if (width < 0) { left = 1; width = -width; } len *= sizeof(wchar_t); adjust = (len < width) ? width - len : 0; cnt = adjust + len; if (left) adjust = -adjust; for ( ; adjust > 0; adjust++) putc(fill, fp); while (wc = *ws++) putwc(wc, fp); for ( ; adjust < 0; adjust--) putc(' ', fp); #endif return cnt; } static size_t strout(char *s, size_t len, int width, int fill, FILE *restrict fp) { int left = 0, adjust, ch, prefix; size_t cnt = 0; if (width < 0) { left = 1; width = -width; } adjust = (len > 0 && len < width) ? width - len : 0; cnt = adjust + len; if (left) adjust = -adjust; if (fill == '0') { if (*s == '-' || *s == '+') prefix = 1; else if (*s == '0' && toupper(s[1]) == 'X') prefix = 2; else prefix = 0; while (prefix--) { putc(*s++, fp); --len; } } for ( ; adjust > 0; adjust--) putc(fill, fp); if (len == -1) { for (cnt = 0; ch = *s++; ++cnt) putc(ch, fp); } else { while (len-- > 0 && (ch = *s++)) putc(ch, fp); } for ( ; adjust < 0; adjust++) putc(' ', fp); return cnt; } int vfprintf(FILE * restrict fp, const char * restrict fmt, va_list va) { int ch, n, flags, width, left, fill, cnt = 0; size_t inc, len; char *s; wchar_t *ws; struct conv conv; char buf[MAXPREC+1]; wchar_t wbuf[2]; va_list va2; va_copy(va2, va); for (cnt = 0; ch = *fmt++; cnt += inc) { if (ch != '%') { putc(ch, fp); inc = 1; continue; } fill = ' '; left = flags = width = 0; conv.prec = -1; conv.base = 10; conv.sign = '\0'; conv.digs = "0123456789ABCDEFX"; flags: switch (*fmt++) { case ' ': if (conv.sign == '\0') conv.sign = ' '; goto flags; case '+': conv.sign = '+'; goto flags; case '#': flags |= ALTFORM; goto flags; case '.': if (*fmt == '*') { fmt++; n = va_arg(va2, int); } else { for (n = 0; isdigit(ch = *fmt); fmt++) n = n * 10 + ch - '0'; } if (n < 0) n = 0; if (n > MAXPREC) n = MAXPREC; conv.prec = n; goto flags; case '*': width = va_arg(va2, int); goto flags; case '-': left = 1; ++fmt; case '1': case '2': case '3': case '4': case '5': case '6': case '7': case '8': case '9': --fmt; for (n = 0; isdigit(ch = *fmt); ++fmt) n = n * 10 + ch - '0'; if (left) n = -n; width = n; goto flags; case '0': fill = '0'; goto flags; case 'l': flags += LONG; goto flags; case 'h': flags += SHORT; goto flags; case '%': ch = '%'; goto cout; case 'c': if (flags & LONG) { wbuf[0] = va_arg(va2, wint_t); wbuf[1] = L'\0'; ws = wbuf; len = 1; goto wstrout; } ch = va_arg(va2, int); cout: buf[0] = ch; buf[1] = '\0'; s = buf; len = 1; goto strout; case 'j': flags |= INTMAX; goto flags; case 't': flags |= PTRDIFF; goto flags; case 'z': flags |= SIZET; goto flags; case 'u': flags |= UNSIGNED; case 'i': case 'd': conv.base = 10; goto numeric; case 'p': flags |= VOIDPTR | ALTFORM; goto numeric16; case 'x': conv.digs = "0123456789abcdefx"; case 'X': numeric16: conv.base = 16; flags |= UNSIGNED; goto numeric; case 'o': conv.base = 8; flags |= UNSIGNED; numeric: if (conv.prec != -1) fill = ' '; s = numtostr(getnum(&va2, flags, &conv.sign), flags, &conv, &buf[MAXPREC]); len = &buf[MAXPREC] - s; goto strout; case 'L': case 'a': case 'A': case 'e': case 'E': case 'f': case 'g': case 'G': /* TODO */ break; case 's': if (flags & LONG) { ws = va_arg(va2, wchar_t *); /* len = wcsnlen(ws, conv.prec); */ goto wstrout; } else { s = va_arg(va2, char *); if ((len = strlen(s)) > conv.prec) len = conv.prec; goto strout; } wstrout: inc = wstrout(ws, len, width, fill, fp); break; strout: inc = strout(s, len, width, fill, fp); break; case 'n': savecnt(&va2, flags, cnt); break; case '\0': goto out_loop; } } out_loop: return (ferror(fp)) ? EOF : cnt; }