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From: david.laight.linux@gmail.com
To: "Willy Tarreau" <w@1wt.eu>,
	"Thomas Weißschuh" <linux@weissschuh.net>,
	linux-kernel@vger.kernel.org, "Cheng Li" <lechain@gmail.com>
Cc: David Laight <david.laight.linux@gmail.com>
Subject: [PATCH v4 next 15/23] tools/nolibc/printf: Add support for length modifiers tzqL and formats iX
Date: Mon,  2 Mar 2026 10:18:07 +0000	[thread overview]
Message-ID: <20260302101815.3043-16-david.laight.linux@gmail.com> (raw)
In-Reply-To: <20260302101815.3043-1-david.laight.linux@gmail.com>

From: David Laight <david.laight.linux@gmail.com>

Length modifiers t (ptrdiff_t) and z (size_t) are aliases for l (long),
q and L are 64bit the same as j (intmax).
Format i is an alias for d and X similar to x but uppper case.
Supporting them is mostly just adding the relavant bit to the bit
pattern used for maching characters.
Although %X is detected the output will be lower case.

Change/add tests to use conversions i and X, and length modifiers L and ll.
Use the correct minimum value for "%Li".

Acked-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: David Laight <david.laight.linux@gmail.com>
---

v4: Split from the previous patch.

 tools/include/nolibc/stdio.h                 | 27 ++++++++++++--------
 tools/testing/selftests/nolibc/nolibc-test.c | 14 +++++++---
 2 files changed, 27 insertions(+), 14 deletions(-)

diff --git a/tools/include/nolibc/stdio.h b/tools/include/nolibc/stdio.h
index ea1288d87eea..4c7626dbd63f 100644
--- a/tools/include/nolibc/stdio.h
+++ b/tools/include/nolibc/stdio.h
@@ -291,10 +291,11 @@ int fseek(FILE *stream, long offset, int whence)
 }
 
 
-/* printf(). Supports the following integer and string formats.
- *  - %[#-+ 0][width][{l,ll,j}]{c,d,u,x,p,s,m,%}
+/* printf(). Supports most of the normal integer and string formats.
+ *  - %[#-+ 0][width][{l,t,z,ll,L,j,q}]{c,d,i,u,x,X,p,s,m,%}
  *  - %% generates a single %
  *  - %m outputs strerror(errno).
+ *  - %X outputs a..f the same as %x.
  *  - The modifiers [#-+ 0] are currently ignored.
  *  - No support for precision or variable widths.
  *  - No support for floating point or wide characters.
@@ -386,9 +387,11 @@ int __nolibc_printf(__nolibc_printf_cb cb, void *state, const char *fmt, va_list
 
 		/* Length modifier.
 		 * They miss the conversion flags characters " #+-0" so can go into flags.
-		 * Change ll to j (both always 64bits).
+		 * Change both L and ll to j (all alwys 64bit).
 		 */
-		ch_flag = _NOLIBC_PF_CHAR_IS_ONE_OF(ch, 'l', 'j');
+		if (ch == 'L')
+			ch = 'j';
+		ch_flag = _NOLIBC_PF_CHAR_IS_ONE_OF(ch, 'l', 't', 'z', 'j', 'q');
 		if (ch_flag != 0) {
 			if (ch == 'l' && fmt[0] == 'l') {
 				fmt++;
@@ -403,20 +406,22 @@ int __nolibc_printf(__nolibc_printf_cb cb, void *state, const char *fmt, va_list
 		/* Numeric and pointer conversion specifiers.
 		 *
 		 * Use an explicit bound check (rather than _NOLIBC_PF_CHAR_IS_ONE_OF())
-		 * so ch_flag can be used later.
+		 * so that 'X' can be allowed through.
+		 * 'X' gets treated and 'x' because _NOLIBC_PF_FLAG() returns the same
+		 * value for both.
 		 */
 		ch_flag = _NOLIBC_PF_FLAG(ch);
-		if ((ch >= 'a' && ch <= 'z') &&
-		    _NOLIBC_PF_FLAGS_CONTAIN(ch_flag, 'c', 'd', 'u', 'x', 'p')) {
+		if (((ch >= 'a' && ch <= 'z') || ch == 'X') &&
+		    _NOLIBC_PF_FLAGS_CONTAIN(ch_flag, 'c', 'd', 'i', 'u', 'x', 'p')) {
 			/* 'long' is needed for pointer conversions and ltz lengths.
 			 * A single test can be used provided 'p' (the same bit as '0')
 			 * is masked from flags.
 			 */
 			if (_NOLIBC_PF_FLAGS_CONTAIN(ch_flag | (flags & ~_NOLIBC_PF_FLAG('p')),
-						     'p', 'l')) {
+						     'p', 'l', 't', 'z')) {
 				v = va_arg(args, unsigned long);
 				signed_v = (long)v;
-			} else if (_NOLIBC_PF_FLAGS_CONTAIN(flags, 'j')) {
+			} else if (_NOLIBC_PF_FLAGS_CONTAIN(flags, 'j', 'q')) {
 				v = va_arg(args, unsigned long long);
 				signed_v = v;
 			} else {
@@ -434,7 +439,7 @@ int __nolibc_printf(__nolibc_printf_cb cb, void *state, const char *fmt, va_list
 
 			out = outbuf;
 
-			if (_NOLIBC_PF_FLAGS_CONTAIN(ch_flag, 'd')) {
+			if (_NOLIBC_PF_FLAGS_CONTAIN(ch_flag, 'd', 'i')) {
 				/* "%d" and "%i" - signed decimal numbers. */
 				if (signed_v < 0) {
 					*out++ = '-';
@@ -444,7 +449,7 @@ int __nolibc_printf(__nolibc_printf_cb cb, void *state, const char *fmt, va_list
 			}
 
 			/* Convert the number to ascii in the required base. */
-			if (_NOLIBC_PF_FLAGS_CONTAIN(ch_flag, 'd', 'u')) {
+			if (_NOLIBC_PF_FLAGS_CONTAIN(ch_flag, 'd', 'i', 'u')) {
 				/* Base 10 */
 				u64toa_r(v, out);
 			} else {
diff --git a/tools/testing/selftests/nolibc/nolibc-test.c b/tools/testing/selftests/nolibc/nolibc-test.c
index 638f18fc5123..a140c54e4d72 100644
--- a/tools/testing/selftests/nolibc/nolibc-test.c
+++ b/tools/testing/selftests/nolibc/nolibc-test.c
@@ -1826,11 +1826,19 @@ static int run_printf(int min, int max)
 		CASE_TEST(number);       EXPECT_VFPRINTF(1, "1234", "%d", 1234); break;
 		CASE_TEST(negnumber);    EXPECT_VFPRINTF(1, "-1234", "%d", -1234); break;
 		CASE_TEST(unsigned);     EXPECT_VFPRINTF(1, "12345", "%u", 12345); break;
+		CASE_TEST(signed_max);   EXPECT_VFPRINTF(1, "2147483647", "%i", ~0u >> 1); break;
+		CASE_TEST(signed_min);   EXPECT_VFPRINTF(1, "-2147483648", "%i", (~0u >> 1) + 1); break;
+		CASE_TEST(unsigned_max); EXPECT_VFPRINTF(1, "4294967295", "%u", ~0u); break;
 		CASE_TEST(char);         EXPECT_VFPRINTF(1, "c", "%c", 'c'); break;
-		CASE_TEST(hex);          EXPECT_VFPRINTF(1, "f", "%x", 0xf); break;
+		CASE_TEST(hex_nolibc);   EXPECT_VFPRINTF(is_nolibc, "|f|d|", "|%x|%X|", 0xf, 0xd); break;
+		CASE_TEST(hex_libc);     EXPECT_VFPRINTF(!is_nolibc, "|f|D|", "|%x|%X|", 0xf, 0xd); break;
 		CASE_TEST(pointer);      EXPECT_VFPRINTF(1, "0x1", "%p", (void *) 0x1); break;
-		CASE_TEST(uintmax_t);    EXPECT_VFPRINTF(1, "18446744073709551615", "%ju", 0xffffffffffffffffULL); break;
-		CASE_TEST(intmax_t);     EXPECT_VFPRINTF(1, "-9223372036854775807", "%jd", 0x8000000000000001LL); break;
+		CASE_TEST(percent);      EXPECT_VFPRINTF(1, "a%d42%69%", "a%%d%d%%%d%%", 42, 69); break;
+		CASE_TEST(perc_qual);    EXPECT_VFPRINTF(1, "a%d2", "a%-14l%d%d", 2); break;
+		CASE_TEST(invalid);      EXPECT_VFPRINTF(1, "a%12yx3%y42%P", "a%12yx%d%y%d%P", 3, 42); break;
+		CASE_TEST(intmax_max);   EXPECT_VFPRINTF(1, "9223372036854775807", "%lld", ~0ULL >> 1); break;
+		CASE_TEST(intmax_min);   EXPECT_VFPRINTF(1, "-9223372036854775808", "%Li", (~0ULL >> 1) + 1); break;
+		CASE_TEST(uintmax_max);  EXPECT_VFPRINTF(1, "18446744073709551615", "%ju", ~0ULL); break;
 		CASE_TEST(truncation);   EXPECT_VFPRINTF(1, "0123456789012345678901234", "%s", "0123456789012345678901234"); break;
 		CASE_TEST(string_width); EXPECT_VFPRINTF(1, "         1", "%10s", "1"); break;
 		CASE_TEST(number_width); EXPECT_VFPRINTF(1, "         1", "%10d", 1); break;
-- 
2.39.5


  parent reply	other threads:[~2026-03-02 10:18 UTC|newest]

Thread overview: 44+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-03-02 10:17 [PATCH v4 next 00/23] Enhance printf() david.laight.linux
2026-03-02 10:17 ` [PATCH v4 next 01/23] tools/nolibc: Add _NOLIBC_OPTIMIZER_HIDE_VAR() to compiler.h david.laight.linux
2026-03-07 10:50   ` Willy Tarreau
2026-03-02 10:17 ` [PATCH v4 next 02/23] tools/nolibc/printf: Move snprintf length check to callback david.laight.linux
2026-03-07 10:48   ` Willy Tarreau
2026-03-02 10:17 ` [PATCH v4 next 03/23] selftests/nolibc: Return correct value when printf test fails david.laight.linux
2026-03-02 10:17 ` [PATCH v4 next 04/23] selftests/nolibc: check vsnprintf() output buffer before the length david.laight.linux
2026-03-02 10:17 ` [PATCH v4 next 05/23] selftests/nolibc: Use length of 'expected' string to check snprintf() output david.laight.linux
2026-03-02 10:17 ` [PATCH v4 next 06/23] selftests/nolibc: Check that snprintf() doesn't write beyond the buffer end david.laight.linux
2026-03-02 10:17 ` [PATCH v4 next 07/23] selftests/nolibc: Let EXPECT_VFPRINTF() tests be skipped david.laight.linux
2026-03-02 10:18 ` [PATCH 08/23] selftests/nolibc: Rename w to written in expect_vfprintf() david.laight.linux
2026-03-02 10:18 ` [PATCH v4 next 09/23] tools/nolibc: Implement strerror() in terms of strerror_r() david.laight.linux
2026-03-07 10:18   ` Willy Tarreau
2026-03-07 11:31     ` David Laight
2026-03-07 11:37       ` Willy Tarreau
2026-03-07 16:55         ` David Laight
2026-03-07 17:17           ` Willy Tarreau
2026-03-02 10:18 ` [PATCH v4 next 10/23] tools/nolibc: Rename the 'errnum' parameter to strerror() david.laight.linux
2026-03-07 10:19   ` Willy Tarreau
2026-03-02 10:18 ` [PATCH v4 next 11/23] tools/nolibc/printf: Output pad characters in 16 byte chunks david.laight.linux
2026-03-02 10:18 ` [PATCH 12/23] tools/nolibc/printf: Simplify __nolibc_printf() david.laight.linux
2026-03-02 10:18 ` [PATCH v4 next 13/23] tools/nolibc/printf: Use goto and reduce indentation david.laight.linux
2026-03-07 10:30   ` Willy Tarreau
2026-03-02 10:18 ` [PATCH 14/23] tools/nolibc/printf: Use bit-masks to hold requested flag, length and conversion chars david.laight.linux
2026-03-02 10:18 ` david.laight.linux [this message]
2026-03-02 10:18 ` [PATCH v4 next 16/23] tools/nolibc/printf: Handle "%s" with the numeric formats david.laight.linux
2026-03-07 10:32   ` Willy Tarreau
2026-03-02 10:18 ` [PATCH 17/23] tools/nolibc/printf: Prepend sign to converted number david.laight.linux
2026-03-07 10:40   ` Willy Tarreau
2026-03-02 10:18 ` [PATCH v4 next 18/23] tools/nolibc/printf: Add support for conversion flags space and plus david.laight.linux
2026-03-07 10:46   ` Willy Tarreau
2026-03-02 10:18 ` [PATCH v4 next 19/23] tools/nolibc/printf: Special case 0 and add support for %#x david.laight.linux
2026-03-07 10:46   ` Willy Tarreau
2026-03-02 10:18 ` [PATCH v4 next 20/23] tools/nolibc/printf: Add support for left aligning fields david.laight.linux
2026-03-07 10:46   ` Willy Tarreau
2026-03-02 10:18 ` [PATCH v4 next 21/23] tools/nolibc/printf: Add support for zero padding and field precision david.laight.linux
2026-03-02 10:18 ` [PATCH v4 next 22/23] tools/nolibc/printf: Add support for octal output david.laight.linux
2026-03-07 10:45   ` Willy Tarreau
2026-03-02 10:18 ` [PATCH v4 next 23/23] selftests/nolibc: Use printf variable field widths and precisions david.laight.linux
2026-03-07 10:53 ` [PATCH v4 next 00/23] Enhance printf() Willy Tarreau
2026-03-07 18:02 ` Thomas Weißschuh
2026-03-07 22:03   ` David Laight
2026-03-07 22:20     ` Thomas Weißschuh
2026-03-08  9:23   ` Willy Tarreau

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