[PATCH v4 16/34] vsprintf: Refactor fourcc_string()

From: Kent Overstreet
Date: Sun Jun 19 2022 - 20:44:13 EST


- We're attempting to consolidate printf_spec and format string
handling in the top level vpr_buf(), this changes fourcc_string() to
not take printf_spec

- With the new printbuf helpers there's no need to use a separate stack
allocated buffer, so this patch deletes it.

Signed-off-by: Kent Overstreet <kent.overstreet@xxxxxxxxx>
---
lib/vsprintf.c | 27 ++++++++++++---------------
1 file changed, 12 insertions(+), 15 deletions(-)

diff --git a/lib/vsprintf.c b/lib/vsprintf.c
index 5e96ab24f5..55a42ae055 100644
--- a/lib/vsprintf.c
+++ b/lib/vsprintf.c
@@ -1726,17 +1726,15 @@ void netdev_bits(struct printbuf *out, const void *addr,

static noinline_for_stack
void fourcc_string(struct printbuf *out, const u32 *fourcc,
- struct printf_spec spec, const char *fmt)
+ const char *fmt)
{
- char output_buf[sizeof("0123 little-endian (0x01234567)")];
- struct printbuf output = PRINTBUF_EXTERN(output_buf, sizeof(output_buf));
unsigned int i;
u32 orig, val;

if (fmt[1] != 'c' || fmt[2] != 'c')
- return error_string_spec(out, "(%p4?)", spec);
+ return error_string(out, "(%p4?)");

- if (check_pointer_spec(out, fourcc, spec))
+ if (check_pointer(out, fourcc))
return;

orig = get_unaligned(fourcc);
@@ -1746,18 +1744,16 @@ void fourcc_string(struct printbuf *out, const u32 *fourcc,
unsigned char c = val >> (i * 8);

/* Print non-control ASCII characters as-is, dot otherwise */
- prt_char(&output, isascii(c) && isprint(c) ? c : '.');
+ prt_char(out, isascii(c) && isprint(c) ? c : '.');
}

- prt_char(&output, ' ');
- prt_str(&output, orig & BIT(31) ? "big-endian" : "little-endian");
-
- prt_char(&output, ' ');
- prt_char(&output, '(');
- special_hex_number(&output, orig, sizeof(u32));
- prt_char(&output, ')');
+ prt_char(out, ' ');
+ prt_str(out, orig & BIT(31) ? "big-endian" : "little-endian");

- string_spec(out, output_buf, spec);
+ prt_char(out, ' ');
+ prt_char(out, '(');
+ special_hex_number(out, orig, sizeof(u32));
+ prt_char(out, ')');
}

static noinline_for_stack
@@ -2361,7 +2357,8 @@ void pointer(struct printbuf *out, const char *fmt,
netdev_bits(out, ptr, fmt);
return do_width_precision(out, prev_pos, spec);
case '4':
- return fourcc_string(out, ptr, spec, fmt);
+ fourcc_string(out, ptr, fmt);
+ return do_width_precision(out, prev_pos, spec);
case 'a':
address_val(out, ptr, fmt);
return do_width_precision(out, prev_pos, spec);
--
2.36.1