ref: 6ce3c0bd14348efbe61ecb6b02c89d62fa1847e4
parent: 128f871fd0d4943b50c2de4b5afcde1b1210ae30
author: Roberto E. Vargas Caballero <k0ga@shike2.com>
date: Sat Dec 2 05:46:59 EST 2017
[lib/c] Rewrite vfprintf.c The previous version was only a proof of concept. This version is intended to be an actual implementation.
--- a/lib/c/src/vfprintf.c
+++ b/lib/c/src/vfprintf.c
@@ -1,73 +1,330 @@
+/*
+ * This file is covered by the license that you can find in the file
+ * LICENSE, but for this file, vfprintf.c, an additional clausule is
+ * added:
+ * - Christopher M. Graff (<cm0graff@gmail.com>) is forbidden to
+ * use, copy, modify and/or distribute this file. He is forbidden
+ * even to read this file, fuck you!.
+ */
+#include <ctype.h>
#include <stdarg.h>
+#include <stdint.h>
#include <stdio.h>
+#include <string.h>
+#include <wchar.h>
#undef vfprintf
-static int
-printn2(FILE * restrict fp, unsigned n, int base)
+enum {
+ LONG = 1 << 0,
+ LLONG = 1 << 1,
+ LADJUST = 1 << 2,
+ SHORT = 1 << 3,
+ CHAR = 1 << 4,
+ SIZET = 1 << 5,
+ PTRDIFF = 1 << 6,
+ INTMAX = 1 << 7,
+ VOIDPTR = 1 << 8,
+ UNSIGNED = 1 << 9,
+ ALTFORM = 1 << 10,
+};
+
+#define BUF_SIZ 50
+
+struct conv {
+ int sign;
+ int prec;
+ char *digs;
+ int base;
+};
+
+static uintmax_t
+getnum(va_list va, int flags, int *sign)
{
- unsigned t;
- int cnt = 0;
- static char digits[] = "0123456789ABCDEF";
+ uintmax_t mask, val;
+ int size;
- if ((t = n / base) != 0)
- cnt += printn2(fp, t, base);
- putc(digits[n % base], fp);
- return cnt + 1;
+ if (flags & CHAR) {
+ val = va_arg(va, int);
+ size = sizeof(char);
+ } else if (flags & SHORT) {
+ val = va_arg(va, int);
+ size = sizeof(short);
+ } else if (flags & LONG) {
+ val = va_arg(va, long);
+ size = sizeof(long);
+ } else if (flags & LLONG) {
+ val = va_arg(va, long long);
+ size = sizeof(long long);
+ } else if (flags & SIZET) {
+ val = va_arg(va, size_t);
+ size = sizeof(size_t);
+ } else if (flags & INTMAX) {
+ val = va_arg(va, intmax_t);
+ size = sizeof(intmax_t);
+ } else if (flags & VOIDPTR) {
+ val = (uintmax_t) va_arg(va, void *);
+ size = sizeof(void*);
+ } else {
+ val = va_arg(va, int);
+ size = sizeof(int);
+ }
+
+ if ((flags & UNSIGNED) == 0 && (intmax_t) val < 0) {
+ *sign = '-';
+ val = -val;
+ }
+ mask = (intmax_t) -1;
+ size = sizeof(uintmax_t) - size;
+ while (size--)
+ mask >>= 8;
+ return val &= mask;
}
+static char *
+numtostr(uintptr_t val, int flags, struct conv *conv, char *buf)
+{
+ char *buf0 = buf;
+ int len, base = conv->base;
+
+ *buf = '\0';
+ do {
+ *--buf = conv->digs[val % base];
+ val /= base;
+ } while (val > 0);
+
+ while (buf0 - buf < conv->prec)
+ *--buf = '0';
+
+ if (flags & ALTFORM) {
+ if (base == 8 && *buf != '0') {
+ *--buf = '0';
+ } else if (base == 16) {
+ *--buf = conv->digs[16];
+ *--buf = '0';
+ }
+ }
+ if (conv->sign)
+ *--buf = conv->sign;
+ return buf;
+}
+
+static void
+setcnt(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 int
-printn(FILE * restrict fp, int n, int b, int sign)
+wstrout(wchar_t *s, int width, int fill, FILE * restrict fp)
{
- int cnt = 0;
+ /* TODO */
+ return 0;
+}
- if (sign && n < 0) {
- n = -n;
- putc('-', fp);
- ++cnt;
+static int
+strout(char *s, int width, int fill, FILE * restrict fp)
+{
+ int left = 1, adjust, ch, len, cnt = 0;
+
+ if (width < 0) {
+ left = -1;
+ width = -width;
}
- cnt += printn2(fp, n, b);
+ len = strlen(s);
+ adjust = (len < width) ? width - len : 0;
+ adjust *= left;
+
+ for ( ; adjust < 0; cnt++, adjust++)
+ putc(fill, fp);
+
+ for ( ; ch = *s++; cnt++)
+ putc(ch, fp);
+
+ for ( ; adjust > 0; cnt++, adjust--)
+ putc(fill, fp);
+
return cnt;
}
+/* TODO: control overflow in cnt */
int
vfprintf(FILE * restrict fp, const char *fmt, va_list va)
{
- int c, base, sign, cnt = 0;
+ int *p, ch, n, flags, width, fill, cnt = 0;
char *s;
+ wchar_t *ws;
+ struct conv conv;
+ char buf[BUF_SIZ+1];
+ wchar_t wbuf[2];
- while ((c = *fmt++) != '\0') {
- if (c == '%') {
- sign = 0;
- switch (*fmt++) {
- case '%':
- c = '%';
- break;
- case 'c':
- c = va_arg(va, int);
- break;
- case 'o':
- base = 8;
- goto numeric;
- case 'd':
- sign = 1;
- base = 10;
- goto numeric;
- case 'x':
- base = 16;
- numeric:
- c = va_arg(va, int);
- cnt += printn(fp, c, base, sign);
- continue;
- case 's':
+ while ((ch = *fmt++) != '\0') {
+ if (ch != '%') {
+ putc(ch, fp);
+ ++cnt;
+ continue;
+ }
+
+ fill = ' ';
+ flags = width = 0;
+ conv.prec = -1;
+ conv.base = 10;
+ conv.sign = '\0';
+ conv.digs = "0123456789ABCDEFX";
+
+flags:
+ switch (*fmt++) {
+ case '%':
+ putc('%', fp);
+ ++cnt;
+ continue;
+ case ' ':
+ conv.sign = ' ';
+ goto flags;
+ case '+':
+ conv.sign = '+';
+ goto flags;
+ case '#':
+ flags |= ALTFORM;
+ goto flags;
+ case '.':
+ if (*fmt == '*') {
+ fmt++;
+ n = va_arg(va, int);
+ } else {
+ for (n = 0; isdigit(ch = *fmt); fmt++)
+ n = n * 10 + ch - '0';
+ }
+ if (n > BUF_SIZ)
+ n = BUF_SIZ;
+ if (n > 0)
+ conv.prec = n;
+ goto flags;
+ case '-':
+ flags |= LADJUST;
+ goto flags;
+ case '*':
+ n = va_arg(va, int);
+ if (n < 0) {
+ flags |= LADJUST;
+ n = -n;
+ }
+ width = n;
+ goto flags;
+ 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';
+ width = n;
+ goto flags;
+ case '0':
+ fill = '0';
+ goto flags;
+ case 'l':
+ flags += LONG;
+ goto flags;
+ case 'h':
+ flags += SHORT;
+ goto flags;
+ case 'c':
+ if (flags & LONG) {
+ wbuf[0] = va_arg(va, wint_t);
+ wbuf[1] = '\0';
+ ws = wbuf;
+ goto wstrout;
+ } else {
+ buf[0] = va_arg(va, int);
+ buf[1] = '\0';
+ s = buf;
+ 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':
+ numeric10:
+ 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:
+ s = numtostr(getnum(va, flags, &conv.sign),
+ flags,
+ &conv,
+ &buf[BUF_SIZ]);
+ goto strout;
+ case 'L':
+ case 'a':
+ case 'A':
+ case 'e':
+ case 'E':
+ case 'f':
+ case 'g':
+ case 'G':
+ /* TODO */
+ case 's':
+ if ((flags & LONG) == 0){
s = va_arg(va, char *);
- while ((c = *s++) != '\0')
- putc(c, fp);
- default:
- continue;
+ goto strout;
}
+ ws = va_arg(va, wchar_t *);
+ wstrout:
+ if (flags & LADJUST)
+ width = -width;
+ cnt += wstrout(ws, width, fill, fp);
+ break;
+ strout:
+ if (flags & LADJUST)
+ width = -width;
+ cnt += strout(s, width, fill, fp);
+ break;
+ case 'n':
+ setcnt(va, flags, cnt);
+ break;
+ case '\0':
+ goto end_format;
}
- putc(c, fp);
- ++cnt;
}
- return cnt;
+end_format:
+ return (ferror(fp)) ? EOF : cnt;
}