Nixyri/godot
1
0
Fork 0
mirror of https://github.com/godotengine/godot.git synced 2024-11-25 13:43:15 +00:00
Code Issues Actions Packages Projects Releases Wiki Activity

Fix platform-dependent hashing for char* and wchar_t*

Browse Source 
Since char/wchar_t can be either signed or unsigned, its conversion to uint32_t leads to different values depending on platform.
In particular, the same string represented as char* (Latin-1; StringName direct construction) or uint32_t (UTF-8; constructed
via String) previously resulted in different hashes.
This commit is contained in:
Jan Haller 2023-09-24 15:58:28 +02:00
parent ed3015e979
commit 43be9fa0c8
1 changed files with 14 additions and 6 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

20
core/string/ustring.cpp
View File

@ -2763,12 +2763,13 @@ double String::to_float() const {
}
uint32_t String::hash(const char *p_cstr) {
// static_cast: avoid negative values on platforms where char is signed.
uint32_t hashv = 5381;
uint32_t c = *p_cstr++;
uint32_t c = static_cast<uint8_t>(*p_cstr++);
while (c) {
hashv = ((hashv << 5) + hashv) + c; /* hash * 33 + c */
c = *p_cstr++;
c = static_cast<uint8_t>(*p_cstr++);
}
return hashv;
@ -2777,28 +2778,35 @@ uint32_t String::hash(const char *p_cstr) {
uint32_t String::hash(const char *p_cstr, int p_len) {
uint32_t hashv = 5381;
for (int i = 0; i < p_len; i++) {
hashv = ((hashv << 5) + hashv) + p_cstr[i]; /* hash * 33 + c */
// static_cast: avoid negative values on platforms where char is signed.
hashv = ((hashv << 5) + hashv) + static_cast<uint8_t>(p_cstr[i]); /* hash * 33 + c */
}
return hashv;
}
uint32_t String::hash(const wchar_t *p_cstr, int p_len) {
// Avoid negative values on platforms where wchar_t is signed. Account for different sizes.
using wide_unsigned = std::conditional<sizeof(wchar_t) == 2, uint16_t, uint32_t>::type;
uint32_t hashv = 5381;
for (int i = 0; i < p_len; i++) {
hashv = ((hashv << 5) + hashv) + p_cstr[i]; /* hash * 33 + c */
hashv = ((hashv << 5) + hashv) + static_cast<wide_unsigned>(p_cstr[i]); /* hash * 33 + c */
}
return hashv;
}
uint32_t String::hash(const wchar_t *p_cstr) {
// Avoid negative values on platforms where wchar_t is signed. Account for different sizes.
using wide_unsigned = std::conditional<sizeof(wchar_t) == 2, uint16_t, uint32_t>::type;
uint32_t hashv = 5381;
uint32_t c = *p_cstr++;
uint32_t c = static_cast<wide_unsigned>(*p_cstr++);
while (c) {
hashv = ((hashv << 5) + hashv) + c; /* hash * 33 + c */
c = *p_cstr++;
c = static_cast<wide_unsigned>(*p_cstr++);
}
return hashv;