awk: allow printf('%c') to output NUL, closes 13486

Treat the output of printf as binary rather than a null-terminated
string so that NUL characters can be output.

This is considered to be a GNU extension, though it's also available
in mawk and FreeBSD's awk.

function                                             old     new   delta
evaluate                                            3487    3504     +17
awk_printf                                           504     519     +15
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 2/0 up/down: 32/0)               Total: 32 bytes

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
This commit is contained in:
Ron Yorston 2021-01-27 11:19:14 +00:00 committed by Denys Vlasenko
parent f3a55b306e
commit e8fe9f9635
2 changed files with 20 additions and 3 deletions

View File

@ -2155,7 +2155,10 @@ static int fmt_num(char *b, int size, const char *format, double n, int int_as_i
}
/* formatted output into an allocated buffer, return ptr to buffer */
static char *awk_printf(node *n)
#if !ENABLE_FEATURE_AWK_GNU_EXTENSIONS
# define awk_printf(a, b) awk_printf(a)
#endif
static char *awk_printf(node *n, int *len)
{
char *b = NULL;
char *fmt, *s, *f;
@ -2209,6 +2212,10 @@ static char *awk_printf(node *n)
nvfree(v);
b = xrealloc(b, i + 1);
b[i] = '\0';
#if ENABLE_FEATURE_AWK_GNU_EXTENSIONS
if (len)
*len = i;
#endif
return b;
}
@ -2666,6 +2673,7 @@ static var *evaluate(node *op, var *res)
case XC( OC_PRINT ):
case XC( OC_PRINTF ): {
FILE *F = stdout;
IF_FEATURE_AWK_GNU_EXTENSIONS(int len;)
if (op->r.n) {
rstream *rsm = newfile(R.s);
@ -2703,8 +2711,12 @@ static var *evaluate(node *op, var *res)
fputs(getvar_s(intvar[ORS]), F);
} else { /* OC_PRINTF */
char *s = awk_printf(op1);
char *s = awk_printf(op1, &len);
#if ENABLE_FEATURE_AWK_GNU_EXTENSIONS
fwrite(s, len, 1, F);
#else
fputs(s, F);
#endif
free(s);
}
fflush(F);
@ -2978,7 +2990,7 @@ static var *evaluate(node *op, var *res)
break;
case XC( OC_SPRINTF ):
setvar_p(res, awk_printf(op1));
setvar_p(res, awk_printf(op1, NULL));
break;
case XC( OC_UNARY ): {

View File

@ -383,6 +383,11 @@ testing "awk errors on missing delete arg" \
"awk -e '{delete}' 2>&1" "awk: cmd. line:1: Too few arguments\n" "" ""
SKIP=
optional FEATURE_AWK_GNU_EXTENSIONS
testing "awk printf('%c') can output NUL" \
"awk '{printf(\"hello%c null\n\", 0)}'" "hello\0 null\n" "" "\n"
SKIP=
# testing "description" "command" "result" "infile" "stdin"
testing 'awk negative field access' \
'awk 2>&1 -- '\''{ $(-1) }'\' \