| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-Id: <20220207162354.14293-18-w@1wt.eu>
Date: Mon, 7 Feb 2022 17:23:29 +0100
From: Willy Tarreau <w@....eu>
To: "Paul E . McKenney" <paulmck@...nel.org>
Cc: Mark Brown <broonie@...nel.org>, linux-kernel@...r.kernel.org,
Willy Tarreau <w@....eu>
Subject: [PATCH 17/42] tools/nolibc/stdlib: add utoh() and u64toh()
This adds a pair of functions to emit hex values.
Signed-off-by: Willy Tarreau <w@....eu>
---
tools/include/nolibc/stdlib.h | 80 +++++++++++++++++++++++++++++++++++
1 file changed, 80 insertions(+)
diff --git a/tools/include/nolibc/stdlib.h b/tools/include/nolibc/stdlib.h
index d972871bf2ba..82a4cf606d3c 100644
--- a/tools/include/nolibc/stdlib.h
+++ b/tools/include/nolibc/stdlib.h
@@ -52,6 +52,46 @@ int atoi(const char *s)
return atol(s);
}
+/* Converts the unsigned long integer <in> to its hex representation into
+ * buffer <buffer>, which must be long enough to store the number and the
+ * trailing zero (17 bytes for "ffffffffffffffff" or 9 for "ffffffff"). The
+ * buffer is filled from the first byte, and the number of characters emitted
+ * (not counting the trailing zero) is returned. The function is constructed
+ * in a way to optimize the code size and avoid any divide that could add a
+ * dependency on large external functions.
+ */
+static __attribute__((unused))
+int utoh_r(unsigned long in, char *buffer)
+{
+ signed char pos = (~0UL > 0xfffffffful) ? 60 : 28;
+ int digits = 0;
+ int dig;
+
+ do {
+ dig = in >> pos;
+ in -= (uint64_t)dig << pos;
+ pos -= 4;
+ if (dig || digits || pos < 0) {
+ if (dig > 9)
+ dig += 'a' - '0' - 10;
+ buffer[digits++] = '0' + dig;
+ }
+ } while (pos >= 0);
+
+ buffer[digits] = 0;
+ return digits;
+}
+
+/* converts unsigned long <in> to an hex string using the static itoa_buffer
+ * and returns the pointer to that string.
+ */
+static inline __attribute__((unused))
+char *utoh(unsigned long in)
+{
+ utoh_r(in, itoa_buffer);
+ return itoa_buffer;
+}
+
/* Converts the unsigned long integer <in> to its string representation into
* buffer <buffer>, which must be long enough to store the number and the
* trailing zero (21 bytes for 18446744073709551615 in 64-bit, 11 for
@@ -144,6 +184,46 @@ char *utoa(unsigned long in)
return itoa_buffer;
}
+/* Converts the unsigned 64-bit integer <in> to its hex representation into
+ * buffer <buffer>, which must be long enough to store the number and the
+ * trailing zero (17 bytes for "ffffffffffffffff"). The buffer is filled from
+ * the first byte, and the number of characters emitted (not counting the
+ * trailing zero) is returned. The function is constructed in a way to optimize
+ * the code size and avoid any divide that could add a dependency on large
+ * external functions.
+ */
+static __attribute__((unused))
+int u64toh_r(uint64_t in, char *buffer)
+{
+ signed char pos = 60;
+ int digits = 0;
+ int dig;
+
+ do {
+ dig = in >> pos;
+ in -= (uint64_t)dig << pos;
+ pos -= 4;
+ if (dig || digits || pos < 0) {
+ if (dig > 9)
+ dig += 'a' - '0' - 10;
+ buffer[digits++] = '0' + dig;
+ }
+ } while (pos >= 0);
+
+ buffer[digits] = 0;
+ return digits;
+}
+
+/* converts uint64_t <in> to an hex string using the static itoa_buffer and
+ * returns the pointer to that string.
+ */
+static inline __attribute__((unused))
+char *u64toh(uint64_t in)
+{
+ u64toh_r(in, itoa_buffer);
+ return itoa_buffer;
+}
+
/* Converts the unsigned 64-bit integer <in> to its string representation into
* buffer <buffer>, which must be long enough to store the number and the
* trailing zero (21 bytes for 18446744073709551615). The buffer is filled from
--
2.35.1
Powered by blists - more mailing lists