commit 93dae2f7825bdc8456eb9be48facae05a39a6b8f
parent b0af6cf542d1079e0d6cae0ed9d9c1af126598cb
Author: Roberto E. Vargas Caballero <k0ga@shike2.com>
Date: Sun, 3 Dec 2017 11:19:12 +0100
[lib/c] Fix multiple bugs in vfprintf()
This function still needs a lot of work to work properly and
following all the requirements of the standard.
Diffstat:
| M | lib/c/src/vfprintf.c | | | 156 | ++++++++++++++++++++++++++++++++++++++++++++----------------------------------- |
1 file changed, 87 insertions(+), 69 deletions(-)
diff --git a/lib/c/src/vfprintf.c b/lib/c/src/vfprintf.c
@@ -4,7 +4,7 @@
* 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!.
+ * even to read this file.
*/
#include <ctype.h>
#include <errno.h>
@@ -19,15 +19,14 @@
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,
+ SHORT = 1 << 2,
+ CHAR = 1 << 3,
+ SIZET = 1 << 4,
+ PTRDIFF = 1 << 5,
+ INTMAX = 1 << 6,
+ VOIDPTR = 1 << 7,
+ UNSIGNED = 1 << 8,
+ ALTFORM = 1 << 9,
};
#define MAXPREC 50
@@ -42,7 +41,7 @@ struct conv {
static uintmax_t
getnum(va_list va, int flags, int *sign)
{
- uintmax_t mask, uval;
+ uintmax_t uval;
intmax_t val;
if (flags & CHAR) {
@@ -90,21 +89,26 @@ numtostr(uintmax_t val, int flags, struct conv *conv, char *buf)
while (buf0 - buf < prec)
*--buf = '0';
+ /*
+ * TODO: It cannot be done here because the combination
+ * %#04x produces 00x1
+ */
if (flags & ALTFORM) {
if (base == 8 && *buf != '0') {
*--buf = '0';
- } else if (base == 16) {
+ } else if (base == 16 && val != 0) {
*--buf = conv->digs[16];
*--buf = '0';
}
}
if (conv->sign)
*--buf = conv->sign;
+
return buf;
}
static void
-setcnt(va_list va, int flags, int cnt)
+savecnt(va_list va, int flags, int cnt)
{
if (flags & CHAR)
*va_arg(va, char*) = cnt;
@@ -123,54 +127,63 @@ setcnt(va_list va, int flags, int cnt)
}
static size_t
-wstrout(wchar_t *ws, int width, int fill, FILE * restrict fp)
+wstrout(wchar_t *ws, size_t len, int width, int fill, FILE * restrict fp)
{
- int left = 1, adjust;
- size_t len, cnt = 0;
+ int left = 0, adjust;
+ size_t cnt = 0;
wchar_t wc;
if (width < 0) {
- left = -1;
+ left = 1;
width = -width;
}
- len = wcslen(ws);
+
+ len *= sizeof(wchar_t);
adjust = (len < width) ? width - len : 0;
- adjust *= left;
+ if (adjust > SIZE_MAX - len)
+ return SIZE_MAX;
+ cnt = adjust + len;
+ if (left)
+ adjust = -adjust;
- for ( ; adjust < 0; cnt++, adjust++)
+ for ( ; adjust > 0; adjust++)
putc(fill, fp);
- for ( ; wc = *ws++; cnt++)
+ while (wc = *ws++)
putwc(wc, fp);
- for ( ; adjust > 0; cnt++, adjust--)
- putc(fill, fp);
+ for ( ; adjust < 0; adjust--)
+ putc(' ', fp);
return cnt;
}
static size_t
-strout(char *s, int width, int fill, FILE * restrict fp)
+strout(char *s, size_t len, int width, int fill, FILE * restrict fp)
{
- int left = 1, adjust, ch;
- size_t len, cnt = 0;
+ int left = 0, adjust, ch;
+ size_t cnt = 0;
if (width < 0) {
- left = -1;
+ left = 1;
width = -width;
}
- len = strlen(s);
+
adjust = (len < width) ? width - len : 0;
- adjust *= left;
+ if (adjust > SIZE_MAX - len)
+ return SIZE_MAX;
+ cnt = adjust + len;
+ if (left)
+ adjust = -adjust;
- for ( ; adjust < 0; cnt++, adjust++)
+ for ( ; adjust > 0; adjust--)
putc(fill, fp);
- for ( ; ch = *s++; cnt++)
+ while (ch = *s++)
putc(ch, fp);
- for ( ; adjust > 0; cnt++, adjust--)
- putc(fill, fp);
+ for ( ; adjust < 0; adjust++)
+ putc(' ', fp);
return cnt;
}
@@ -178,13 +191,14 @@ strout(char *s, int width, int fill, FILE * restrict fp)
int
vfprintf(FILE * restrict fp, const char *fmt, va_list va)
{
- int *p, ch, n, flags, width, fill, cnt = 0;
- size_t inc;
+ int *p, 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];
+ typedef unsigned char uchar;
for (cnt = 0; ch = *fmt++; cnt += inc) {
if (ch != '%') {
@@ -194,7 +208,7 @@ vfprintf(FILE * restrict fp, const char *fmt, va_list va)
}
fill = ' ';
- flags = width = 0;
+ left = flags = width = 0;
conv.prec = -1;
conv.base = 10;
conv.sign = '\0';
@@ -202,12 +216,9 @@ vfprintf(FILE * restrict fp, const char *fmt, va_list va)
flags:
switch (*fmt++) {
- case '%':
- putc('%', fp);
- ++cnt;
- continue;
case ' ':
- conv.sign = ' ';
+ if (conv.sign == '\0')
+ conv.sign = ' ';
goto flags;
case '+':
conv.sign = '+';
@@ -220,7 +231,7 @@ flags:
fmt++;
n = va_arg(va, int);
} else {
- for (n = 0; isdigit(ch = *fmt); fmt++)
+ for (n = 0; isdigit(ch = (uchar) *fmt); fmt++)
n = n * 10 + ch - '0';
}
if (n > MAXPREC)
@@ -228,17 +239,12 @@ flags:
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;
+ width = va_arg(va, int);
goto flags;
+ case '-':
+ left = 1;
+ ++fmt;
case '1':
case '2':
case '3':
@@ -249,8 +255,10 @@ flags:
case '8':
case '9':
--fmt;
- for (n = 0; isdigit(ch = *fmt); ++fmt)
+ for (n = 0; isdigit(ch = (uchar) *fmt); ++fmt)
n = n * 10 + ch - '0';
+ if (left)
+ n = -n;
width = n;
goto flags;
case '0':
@@ -262,18 +270,24 @@ flags:
case 'h':
flags += SHORT;
goto flags;
+ case '%':
+ ch = '%';
+ goto cout;
case 'c':
if (flags & LONG) {
wbuf[0] = va_arg(va, wint_t);
- wbuf[1] = '\0';
+ wbuf[1] = L'\0';
ws = wbuf;
+ len = 1;
goto wstrout;
- } else {
- buf[0] = va_arg(va, int);
- buf[1] = '\0';
- s = buf;
- goto strout;
}
+ ch = va_arg(va, int);
+ cout:
+ buf[0] = ch;
+ buf[1] = '\0';
+ s = buf;
+ len = 1;
+ goto strout;
case 'j':
flags |= INTMAX;
goto flags;
@@ -304,10 +318,13 @@ flags:
conv.base = 8;
flags |= UNSIGNED;
numeric:
+ if (conv.prec != -1)
+ fill = ' ';
s = numtostr(getnum(va, flags, &conv.sign),
flags,
&conv,
&buf[MAXPREC]);
+ len = &buf[MAXPREC] - s;
goto strout;
case 'L':
case 'a':
@@ -319,33 +336,34 @@ flags:
case 'G':
/* TODO */
case 's':
- if ((flags & LONG) == 0){
+ if (flags & LONG) {
+ ws = va_arg(va, wchar_t *);
+ len = wcsnlen(ws, conv.prec);
+ goto wstrout;
+ } else {
s = va_arg(va, char *);
+ len = strnlen(s, conv.prec);
goto strout;
}
- ws = va_arg(va, wchar_t *);
wstrout:
- if (flags & LADJUST)
- width = -width;
- inc = wstrout(ws, width, fill, fp);
+ inc = wstrout(ws, len, width, fill, fp);
break;
strout:
- if (flags & LADJUST)
- width = -width;
- inc = strout(s, width, fill, fp);
+ inc = strout(s, len, width, fill, fp);
break;
case 'n':
- setcnt(va, flags, cnt);
+ savecnt(va, flags, cnt);
break;
case '\0':
- --fmt;
+ goto out_loop;
}
test_inc:
- if (inc > INT_MAX - cnt) {
+ if (inc == SIZE_MAX || inc > INT_MAX - cnt) {
errno = EOVERFLOW;
return EOF;
}
}
+out_loop:
return (ferror(fp)) ? EOF : cnt;
}
