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WJiangzhi wants to merge 1 commit into from
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Unify ZAC_CHAR handling for cross-platform signedness differences #7

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16 changes: 8 additions & 8 deletions ZACLib/ZACLib.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -20,7 +20,7 @@ namespace ZACLib {
if (from.empty()) return;
if (from.size() > max_rule_len) max_rule_len = from.size();
int node = 0;
for (const char i : from) {
for (const ZAC_CHAR i : from) {
const auto c = static_cast<unsigned char>(i);
if (trie[node].next[c] == -1) {
trie[node].next[c] = trie.size(); // NOLINT(*-narrowing-conversions)
Expand All @@ -32,7 +32,7 @@ namespace ZACLib {
if (from.size() > trie[node].match_len) {
trie[node].output_id = outputs.size(); // NOLINT(*-narrowing-conversions)
trie[node].match_len = from.size();
outputs.emplace_back(to.data(), to.size());
outputs.emplace_back(reinterpret_cast<const char*>(to.data()), to.size());
}
}

Expand Down Expand Up @@ -82,7 +82,7 @@ namespace ZACLib {

if (input.empty()) return result;
if (max_rule_len == 0) {
result.append(input.data(), input.size());
result.append(reinterpret_cast<const char*>(input.data()), input.size());
return result;
}

Expand Down Expand Up @@ -130,15 +130,15 @@ namespace ZACLib {
continue;
}

result.append(input.data() + last_pos, cursor - last_pos);
result.append(reinterpret_cast<const char*>(input.data() + last_pos), cursor - last_pos);
result.append(outputs[best_output]);
cursor += best_len;
last_pos = cursor;
}
};

for (size_t i = 0; i < input.size(); ++i) {
const unsigned char c = input[i];
const auto c = static_cast<unsigned char>(input[i]);
state = trie[state].next[c];

if (trie[state].output_id != invalid_output) {
Expand All @@ -154,7 +154,7 @@ namespace ZACLib {
emit_until(input.size());

if (last_pos < input.size()) {
result.append(input.data() + last_pos, input.size() - last_pos);
result.append(reinterpret_cast<const char*>(input.data() + last_pos), input.size() - last_pos);
}

return result;
Expand All @@ -168,7 +168,7 @@ namespace ZACLib {
void Search::AddRule(const ZAC_SV& from) {
if (from.empty()) return;
int node = 0;
for (const char i : from) {
for (const ZAC_CHAR i : from) {
const auto c = static_cast<unsigned char>(i);
if (trie[node].next[c] == -1) {
trie[node].next[c] = trie.size(); // NOLINT(*-narrowing-conversions)
Expand All @@ -180,7 +180,7 @@ namespace ZACLib {
if (from.size() > trie[node].match_len) {
trie[node].output_id = outputs.size(); // NOLINT(*-narrowing-conversions)
trie[node].match_len = from.size();
outputs.emplace_back(from.data(), from.size());
outputs.emplace_back(reinterpret_cast<const char*>(from.data()), from.size());
}
}

Expand Down
31 changes: 19 additions & 12 deletions ZACLib/ZACLib_Types.hpp
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Original file line number Diff line number Diff line change
Expand Up @@ -16,28 +16,35 @@
#include <array>
#include <limits>

#if defined(__ANDROID__) || defined(__arm__) || defined(__aarch64__)
using ZAC_CHAR = unsigned char;
#else
using ZAC_CHAR = char;
#endif


namespace ZACLib {
#if __cplusplus >= 201703L
using ZAC_SV = std::string_view;
using ZAC_SV = std::basic_string_view<ZAC_CHAR>;
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@gemini-code-assist gemini-code-assist Bot Mar 3, 2026

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high

On platforms where ZAC_CHAR is unsigned char (e.g., ARM/Android), aliasing ZAC_SV directly to std::basic_string_view<ZAC_CHAR> breaks API compatibility for C++17 and later. Code that passes string literals or std::string objects to functions expecting a ZAC_SV will fail to compile because there's no implicit conversion from std::string (which uses char) to std::basic_string_view<unsigned char>.

To fix this while retaining the benefits of std::string_view, ZAC_SV can be a wrapper class that inherits from std::basic_string_view<ZAC_CHAR> and provides the necessary constructor from std::string.

class ZAC_SV : public std::basic_string_view<ZAC_CHAR> {
    public:
        using std::basic_string_view<ZAC_CHAR>::basic_string_view;
        ZAC_SV() = default;
        ZAC_SV(const std::string& s) noexcept
            : std::basic_string_view<ZAC_CHAR>(reinterpret_cast<const ZAC_CHAR*>(s.data()), s.size())
        {}
    };

#else
class ZAC_SV {
const char* m_data;
const ZAC_CHAR* m_data;
const size_t m_size;
public:
ZAC_SV() : m_data(nullptr),
m_size(0) {}

ZAC_SV(const char* d, const size_t s) : m_data(d),
ZAC_SV(const ZAC_CHAR* d, const size_t s) : m_data(d),
m_size(s) {}

ZAC_SV(const std::string& s) : m_data(s.c_str()),
// ReSharper disable once CppRedundantCastExpression
ZAC_SV(const std::string& s) : m_data(reinterpret_cast<const ZAC_CHAR*>(s.c_str())),
m_size(s.size()) {} // 模仿std::string_view，不禁止隐式构造

ZAC_SV(const char* d) : m_data(d),
m_size(d ? std::strlen(d) : 0) {} // 模仿std::string_view，不禁止隐式构造
ZAC_SV(const ZAC_CHAR* d) : m_data(d),
m_size(d ? std::strlen(reinterpret_cast<const char*>(d)) : 0) {} // 模仿std::string_view，不禁止隐式构造

const char* data() const noexcept {
const ZAC_CHAR* data() const noexcept {
return m_data;
}

Expand All @@ -49,12 +56,12 @@ namespace ZACLib {
return m_size == 0;
}

const char* begin() const { return m_data; }
const char* end() const { return m_data + m_size; }
const char* cbegin() const { return m_data; }
const char* cend() const { return m_data + m_size; }
const ZAC_CHAR* begin() const { return m_data; }
const ZAC_CHAR* end() const { return m_data + m_size; }
const ZAC_CHAR* cbegin() const { return m_data; }
const ZAC_CHAR* cend() const { return m_data + m_size; }

const char& operator[](const size_t i) const { return m_data[i]; }
const ZAC_CHAR& operator[](const size_t i) const { return m_data[i]; }
};
#endif

Expand Down
47 changes: 27 additions & 20 deletions ZACLib/ZACLib_single.hpp
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Original file line number Diff line number Diff line change
Expand Up @@ -31,29 +31,36 @@
#include <array>
#include <limits>

#if defined(__ANDROID__) || defined(__arm__) || defined(__aarch64__)
using ZAC_CHAR = unsigned char;
#else
using ZAC_CHAR = char;
#endif


namespace ZACLib {
#if __cplusplus >= 201703L
using ZAC_SV = std::string_view;
using ZAC_SV = std::basic_string_view<ZAC_CHAR>;
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@gemini-code-assist gemini-code-assist Bot Mar 3, 2026

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high

On platforms where ZAC_CHAR is unsigned char (e.g., ARM/Android), aliasing ZAC_SV directly to std::basic_string_view<ZAC_CHAR> breaks API compatibility for C++17 and later. Code that passes string literals or std::string objects to functions expecting a ZAC_SV will fail to compile because there's no implicit conversion from std::string (which uses char) to std::basic_string_view<unsigned char>.

To fix this while retaining the benefits of std::string_view, ZAC_SV can be a wrapper class that inherits from std::basic_string_view<ZAC_CHAR> and provides the necessary constructor from std::string.

class ZAC_SV : public std::basic_string_view<ZAC_CHAR> {
    public:
        using std::basic_string_view<ZAC_CHAR>::basic_string_view;
        ZAC_SV() = default;
        ZAC_SV(const std::string& s) noexcept
            : std::basic_string_view<ZAC_CHAR>(reinterpret_cast<const ZAC_CHAR*>(s.data()), s.size())
        {}
    };

#else
class ZAC_SV {
const char* m_data;
const ZAC_CHAR* m_data;
const size_t m_size;

public:
ZAC_SV() : m_data(nullptr),
m_size(0) {}

ZAC_SV(const char* d, const size_t s) : m_data(d),
ZAC_SV(const ZAC_CHAR* d, const size_t s) : m_data(d),
m_size(s) {}

ZAC_SV(const std::string& s) : m_data(s.c_str()),
// ReSharper disable once CppRedundantCastExpression
ZAC_SV(const std::string& s) : m_data(reinterpret_cast<const ZAC_CHAR*>(s.c_str())),
m_size(s.size()) {} // 模仿std::string_view，不禁止隐式构造

ZAC_SV(const char* d) : m_data(d),
m_size(d ? std::strlen(d) : 0) {} // 模仿std::string_view，不禁止隐式构造
ZAC_SV(const ZAC_CHAR* d) : m_data(d),
m_size(d ? std::strlen(reinterpret_cast<const char*>(d)) : 0) {} // 模仿std::string_view，不禁止隐式构造

const char* data() const noexcept {
const ZAC_CHAR* data() const noexcept {
return m_data;
}

Expand All @@ -65,12 +72,12 @@ namespace ZACLib {
return m_size == 0;
}

const char* begin() const { return m_data; }
const char* end() const { return m_data + m_size; }
const char* cbegin() const { return m_data; }
const char* cend() const { return m_data + m_size; }
const ZAC_CHAR* begin() const { return m_data; }
const ZAC_CHAR* end() const { return m_data + m_size; }
const ZAC_CHAR* cbegin() const { return m_data; }
const ZAC_CHAR* cend() const { return m_data + m_size; }

const char& operator[](const size_t i) const { return m_data[i]; }
const ZAC_CHAR& operator[](const size_t i) const { return m_data[i]; }
};
#endif

Expand Down Expand Up @@ -105,7 +112,7 @@ namespace ZACLib {
if (from.empty()) return;
if (from.size() > max_rule_len) max_rule_len = from.size();
int node = 0;
for (const char i : from) {
for (const ZAC_CHAR i : from) {
const auto c = static_cast<unsigned char>(i);
if (trie[node].next[c] == -1) {
trie[node].next[c] = trie.size(); // NOLINT(*-narrowing-conversions)
Expand All @@ -116,7 +123,7 @@ namespace ZACLib {
if (from.size() > trie[node].match_len) {
trie[node].output_id = outputs.size(); // NOLINT(*-narrowing-conversions)
trie[node].match_len = from.size();
outputs.emplace_back(to.data(), to.size());
outputs.emplace_back(reinterpret_cast<const char*>(to.data()), to.size());
}
}

Expand Down Expand Up @@ -158,7 +165,7 @@ namespace ZACLib {

if (input.empty()) return result;
if (max_rule_len == 0) {
result.append(input.data(), input.size());
result.append(reinterpret_cast<const char*>(input.data()), input.size());
return result;
}

Expand Down Expand Up @@ -206,15 +213,15 @@ namespace ZACLib {
continue;
}

result.append(input.data() + last_pos, cursor - last_pos);
result.append(reinterpret_cast<const char*>(input.data() + last_pos), cursor - last_pos);
result.append(outputs[best_output]);
cursor += best_len;
last_pos = cursor;
}
};

for (size_t i = 0; i < input.size(); ++i) {
const unsigned char c = input[i];
const auto c = static_cast<unsigned char>(input[i]);
state = trie[state].next[c];

if (trie[state].output_id != invalid_output) {
Expand All @@ -230,7 +237,7 @@ namespace ZACLib {
emit_until(input.size());

if (last_pos < input.size()) {
result.append(input.data() + last_pos, input.size() - last_pos);
result.append(reinterpret_cast<const char*>(input.data() + last_pos), input.size() - last_pos);
}

return result;
Expand All @@ -255,7 +262,7 @@ namespace ZACLib {
void AddRule(const ZAC_SV& from) {
if (from.empty()) return;
int node = 0;
for (const char i : from) {
for (const ZAC_CHAR i : from) {
const auto c = static_cast<unsigned char>(i);
if (trie[node].next[c] == -1) {
trie[node].next[c] = trie.size(); // NOLINT(*-narrowing-conversions)
Expand All @@ -266,7 +273,7 @@ namespace ZACLib {
if (from.size() > trie[node].match_len) {
trie[node].output_id = outputs.size(); // NOLINT(*-narrowing-conversions)
trie[node].match_len = from.size();
outputs.emplace_back(from.data(), from.size());
outputs.emplace_back(reinterpret_cast<const char*>(from.data()), from.size());
}
}

Expand Down