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https://bugs.gentoo.org/919100
https://github.com/c-util/c-utf8/issues/4
https://github.com/c-util/c-utf8/commit/4b7cb9f940e45d3c68bf427cdeeaf5da47b03b41
From 4b7cb9f940e45d3c68bf427cdeeaf5da47b03b41 Mon Sep 17 00:00:00 2001
From: David Rheinsberg <david.rheinsberg@gmail.com>
Date: Wed, 4 Jan 2023 14:14:56 +0100
Subject: [PATCH] c-utf8: avoid violating strict-aliasing rules
Use the c_load*() helpers of c-stdaux to avoid the strict aliasing rules
of the C language.
Signed-off-by: David Rheinsberg <david.rheinsberg@gmail.com>
--- a/subprojects/libcutf8-1/src/c-utf8.c
+++ b/subprojects/libcutf8-1/src/c-utf8.c
@@ -17,9 +17,9 @@
#define C_UTF8_ASCII_MASK ((size_t)UINT64_C(0x8080808080808080))
#define C_UTF8_ASCII_SUB ((size_t)UINT64_C(0x0101010101010101))
-static inline int c_utf8_word_is_ascii(const size_t *word) {
+static inline int c_utf8_word_is_ascii(size_t word) {
/* True unless any byte is NULL or has the MSB set. */
- return ((((*word - C_UTF8_ASCII_SUB) | *word) & C_UTF8_ASCII_MASK) == 0);
+ return ((((word - C_UTF8_ASCII_SUB) | word) & C_UTF8_ASCII_MASK) == 0);
}
/**
@@ -37,10 +37,10 @@ static inline int c_utf8_word_is_ascii(const size_t *word) {
* byte, without any upper bound on its length.
*/
_c_public_ void c_utf8_verify_ascii(const char **strp, size_t *lenp) {
- unsigned char *str = (unsigned char *)*strp;
+ const char *str = *strp;
size_t len = lenp ? *lenp : (size_t)-1;
- while (len > 0 && *str < 128) {
+ while (len > 0 && c_load_8(str, 0) < 128) {
if ((void*)c_align_to((unsigned long)str, sizeof(size_t)) == str) {
/*
* If the string is aligned to a word boundary, scan two
@@ -51,8 +51,8 @@ _c_public_ void c_utf8_verify_ascii(const char **strp, size_t *lenp) {
* available.
*/
while (len >= 2 * sizeof(size_t)) {
- if (!c_utf8_word_is_ascii((size_t*)str) ||
- !c_utf8_word_is_ascii(((size_t*)str) + 1))
+ if (!c_utf8_word_is_ascii(c_load(size_t, le, aligned, str, 0)) ||
+ !c_utf8_word_is_ascii(c_load(size_t, le, aligned, str, sizeof(size_t))))
break;
str += 2 * sizeof(size_t);
@@ -63,8 +63,8 @@ _c_public_ void c_utf8_verify_ascii(const char **strp, size_t *lenp) {
/*
* Find the actual end of the ASCII-portion of the string.
*/
- while (len > 0 && *str < 128) {
- if (_c_unlikely_(*str == 0x00))
+ while (len > 0 && c_load_8(str, 0) < 128) {
+ if (_c_unlikely_(c_load_8(str, 0) == 0x00))
goto out;
++str;
--len;
@@ -74,7 +74,7 @@ _c_public_ void c_utf8_verify_ascii(const char **strp, size_t *lenp) {
* The string was not aligned, scan one character at a time until
* it is.
*/
- if (_c_unlikely_(*str == 0x00))
+ if (_c_unlikely_(c_load_8(str, 0) == 0x00))
goto out;
++str;
--len;
@@ -82,7 +82,7 @@ _c_public_ void c_utf8_verify_ascii(const char **strp, size_t *lenp) {
}
out:
- *strp = (char *)str;
+ *strp = str;
if (lenp)
*lenp = len;
}
@@ -104,13 +104,13 @@ _c_public_ void c_utf8_verify_ascii(const char **strp, size_t *lenp) {
* byte, without any upper bound on its length.
*/
_c_public_ void c_utf8_verify(const char **strp, size_t *lenp) {
- unsigned char *str = (unsigned char *)*strp;
+ const char *str = *strp;
size_t len = lenp ? *lenp : (size_t)-1;
/* See Unicode 10.0.0, Chapter 3, Section D92 */
while (len > 0) {
- switch (*str) {
+ switch (c_load_8(str, 0)) {
case 0x00:
goto out;
case 0x01 ... 0x7F:
@@ -123,7 +123,7 @@ _c_public_ void c_utf8_verify(const char **strp, size_t *lenp) {
case 0xC2 ... 0xDF:
if (_c_unlikely_(len < 2))
goto out;
- if (_c_unlikely_(!C_UTF8_CHAR_IS_TAIL(*(str + 1))))
+ if (_c_unlikely_(!C_UTF8_CHAR_IS_TAIL(c_load_8(str, 1))))
goto out;
str += 2;
@@ -133,9 +133,9 @@ _c_public_ void c_utf8_verify(const char **strp, size_t *lenp) {
case 0xE0:
if (_c_unlikely_(len < 3))
goto out;
- if (_c_unlikely_(*(str + 1) < 0xA0 || *(str + 1) > 0xBF))
+ if (_c_unlikely_(c_load_8(str, 1) < 0xA0 || c_load_8(str, 1) > 0xBF))
goto out;
- if (_c_unlikely_(!C_UTF8_CHAR_IS_TAIL(*(str + 2))))
+ if (_c_unlikely_(!C_UTF8_CHAR_IS_TAIL(c_load_8(str, 2))))
goto out;
str += 3;
@@ -145,9 +145,9 @@ _c_public_ void c_utf8_verify(const char **strp, size_t *lenp) {
case 0xE1 ... 0xEC:
if (_c_unlikely_(len < 3))
goto out;
- if (_c_unlikely_(!C_UTF8_CHAR_IS_TAIL(*(str + 1))))
+ if (_c_unlikely_(!C_UTF8_CHAR_IS_TAIL(c_load_8(str, 1))))
goto out;
- if (_c_unlikely_(!C_UTF8_CHAR_IS_TAIL(*(str + 2))))
+ if (_c_unlikely_(!C_UTF8_CHAR_IS_TAIL(c_load_8(str, 2))))
goto out;
str += 3;
@@ -157,9 +157,9 @@ _c_public_ void c_utf8_verify(const char **strp, size_t *lenp) {
case 0xED:
if (_c_unlikely_(len < 3))
goto out;
- if (_c_unlikely_(*(str + 1) < 0x80 || *(str + 1) > 0x9F))
+ if (_c_unlikely_(c_load_8(str, 1) < 0x80 || c_load_8(str, 1) > 0x9F))
goto out;
- if (_c_unlikely_(!C_UTF8_CHAR_IS_TAIL(*(str + 2))))
+ if (_c_unlikely_(!C_UTF8_CHAR_IS_TAIL(c_load_8(str, 2))))
goto out;
str += 3;
@@ -169,9 +169,9 @@ _c_public_ void c_utf8_verify(const char **strp, size_t *lenp) {
case 0xEE ... 0xEF:
if (_c_unlikely_(len < 3))
goto out;
- if (_c_unlikely_(!C_UTF8_CHAR_IS_TAIL(*(str + 1))))
+ if (_c_unlikely_(!C_UTF8_CHAR_IS_TAIL(c_load_8(str, 1))))
goto out;
- if (_c_unlikely_(!C_UTF8_CHAR_IS_TAIL(*(str + 2))))
+ if (_c_unlikely_(!C_UTF8_CHAR_IS_TAIL(c_load_8(str, 2))))
goto out;
str += 3;
@@ -181,11 +181,11 @@ _c_public_ void c_utf8_verify(const char **strp, size_t *lenp) {
case 0xF0:
if (_c_unlikely_(len < 4))
goto out;
- if (_c_unlikely_(*(str + 1) < 0x90 || *(str + 1) > 0xBF))
+ if (_c_unlikely_(c_load_8(str, 1) < 0x90 || c_load_8(str, 1) > 0xBF))
goto out;
- if (_c_unlikely_(!C_UTF8_CHAR_IS_TAIL(*(str + 2))))
+ if (_c_unlikely_(!C_UTF8_CHAR_IS_TAIL(c_load_8(str, 2))))
goto out;
- if (_c_unlikely_(!C_UTF8_CHAR_IS_TAIL(*(str + 3))))
+ if (_c_unlikely_(!C_UTF8_CHAR_IS_TAIL(c_load_8(str, 3))))
goto out;
str += 4;
@@ -195,11 +195,11 @@ _c_public_ void c_utf8_verify(const char **strp, size_t *lenp) {
case 0xF1 ... 0xF3:
if (_c_unlikely_(len < 4))
goto out;
- if (_c_unlikely_(!C_UTF8_CHAR_IS_TAIL(*(str + 1))))
+ if (_c_unlikely_(!C_UTF8_CHAR_IS_TAIL(c_load_8(str, 1))))
goto out;
- if (_c_unlikely_(!C_UTF8_CHAR_IS_TAIL(*(str + 2))))
+ if (_c_unlikely_(!C_UTF8_CHAR_IS_TAIL(c_load_8(str, 2))))
goto out;
- if (_c_unlikely_(!C_UTF8_CHAR_IS_TAIL(*(str + 3))))
+ if (_c_unlikely_(!C_UTF8_CHAR_IS_TAIL(c_load_8(str, 3))))
goto out;
str += 4;
@@ -209,11 +209,11 @@ _c_public_ void c_utf8_verify(const char **strp, size_t *lenp) {
case 0xF4:
if (_c_unlikely_(len < 4))
goto out;
- if (_c_unlikely_(*(str + 1) < 0x80 || *(str + 1) > 0x8F))
+ if (_c_unlikely_(c_load_8(str, 1) < 0x80 || c_load_8(str, 1) > 0x8F))
goto out;
- if (_c_unlikely_(!C_UTF8_CHAR_IS_TAIL(*(str + 2))))
+ if (_c_unlikely_(!C_UTF8_CHAR_IS_TAIL(c_load_8(str, 2))))
goto out;
- if (_c_unlikely_(!C_UTF8_CHAR_IS_TAIL(*(str + 3))))
+ if (_c_unlikely_(!C_UTF8_CHAR_IS_TAIL(c_load_8(str, 3))))
goto out;
str += 4;
@@ -226,7 +226,7 @@ _c_public_ void c_utf8_verify(const char **strp, size_t *lenp) {
}
out:
- *strp = (char *)str;
+ *strp = str;
if (lenp)
*lenp = len;
}
|
