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-rw-r--r--lib/mlibc/options/internal/generic/charcode.cpp244
1 files changed, 0 insertions, 244 deletions
diff --git a/lib/mlibc/options/internal/generic/charcode.cpp b/lib/mlibc/options/internal/generic/charcode.cpp
deleted file mode 100644
index e09d5cd..0000000
--- a/lib/mlibc/options/internal/generic/charcode.cpp
+++ /dev/null
@@ -1,244 +0,0 @@
-
-#include <bits/ensure.h>
-#include <frg/string.hpp>
-#include <mlibc/charcode.hpp>
-#include <mlibc/debug.hpp>
-
-namespace mlibc {
-
-struct utf8_charcode {
- static constexpr bool preserves_7bit_units = true;
- static constexpr bool has_shift_states = false;
-
- struct decode_state {
- decode_state()
- : _progress{0}, _cpoint{0} { }
-
- auto progress() { return _progress; }
- auto cpoint() { return _cpoint; }
-
- charcode_error operator() (code_seq<const char> &seq) {
- auto uc = static_cast<unsigned char>(*seq.it);
- if(!_progress) {
- if(!(uc & 0b1000'0000)) {
- // ASCII-compatible.
- _cpoint = uc;
- }else if((uc & 0b1110'0000) == 0b1100'0000) {
- _cpoint = uc & 0b1'1111;
- _progress = 1;
- }else if((uc & 0b1111'0000) == 0b1110'0000) {
- _cpoint = uc & 0b1111;
- _progress = 2;
- }else if((uc & 0b1111'1000) == 0b1111'0000) {
- _cpoint = uc & 0b111;
- _progress = 3;
- }else{
- // If the highest two bits are 0b10, this is the second (or later) unit.
- // Units with highest five bits = 0b11111 do not occur in valid UTF-8.
- __ensure((uc & 0b1100'0000) == 0b1000'0000
- || (uc & 0b1111'1000) == 0b1111'1000);
- return charcode_error::illegal_input;
- }
- }else{
- // TODO: Return an error.
- __ensure((uc & 0b1100'0000) == 0b1000'0000);
- _cpoint = (_cpoint << 6) | (uc & 0x3F);
- --_progress;
- }
- ++seq.it;
- return charcode_error::null;
- }
-
- private:
- int _progress;
- codepoint _cpoint;
- };
-
- struct encode_state {
- // Encodes a single character from wseq + the current state and stores it in nseq.
- // TODO: Convert decode_state to the same strategy.
- charcode_error operator() (code_seq<char> &nseq, code_seq<const codepoint> &wseq) {
- auto wc = *wseq.it;
- __ensure(wc <= 0x7F && "utf8_charcode cannot encode multibyte chars yet");
- *nseq.it = wc;
- ++wseq.it;
- ++nseq.it;
- return charcode_error::null;
- }
- };
-};
-
-polymorphic_charcode::~polymorphic_charcode() = default;
-
-// For *decoding, this class assumes that:
-// - G::decode_state has members progress() and cpoint().
-// - G::decode_state::progress() >= 0 at all times.
-// TODO: This will be needed on platforms like Windows, where wchar_t is UTF-16.
-// TODO: There, we can use negative __mlibc_mbstate::progress to represent encoding to UTF-16.
-// - If G::decode_state::progress() == 0, the code point (given by cpoint())
-// was decoded successfully.
-template<typename G>
-struct polymorphic_charcode_adapter : polymorphic_charcode {
- polymorphic_charcode_adapter()
- : polymorphic_charcode{G::preserves_7bit_units, G::has_shift_states} { }
-
- charcode_error decode(code_seq<const char> &nseq, code_seq<codepoint> &wseq,
- __mlibc_mbstate &st) override {
- __ensure(!st.__progress); // TODO: Update st with ds.progress() and ds.cpoint().
-
- code_seq<const char> decode_nseq = nseq;
- typename G::decode_state ds;
-
- while(decode_nseq && wseq) {
- // Consume the next code unit.
- if(auto e = ds(decode_nseq); e != charcode_error::null)
- return e;
-
- // Produce a new code point.
- if(!ds.progress()) {
- // "Commit" consumed code units (as there was no decode error).
- nseq.it = decode_nseq.it;
- if(!ds.cpoint()) // Stop on null characters.
- return charcode_error::null;
- *wseq.it = ds.cpoint();
- ++wseq.it;
- }
- }
-
- if(ds.progress())
- return charcode_error::input_underflow;
- return charcode_error::null;
- }
-
- charcode_error decode_wtranscode(code_seq<const char> &nseq, code_seq<wchar_t> &wseq,
- __mlibc_mbstate &st) override {
- __ensure(!st.__progress); // TODO: Update st with ds.progress() and ds.cpoint().
-
- code_seq<const char> decode_nseq = nseq;
- typename G::decode_state ds;
-
- while(decode_nseq && wseq) {
- // Consume the next code unit.
- if(auto e = ds(decode_nseq); e != charcode_error::null)
- return e;
-
- // Produce a new code point.
- if(!ds.progress()) {
- nseq.it = decode_nseq.it;
- // "Commit" consumed code units (as there was no decode error).
- if(!ds.cpoint()) // Stop on null characters.
- return charcode_error::null;
- *wseq.it = ds.cpoint();
- ++wseq.it;
- }
- }
-
- if(ds.progress())
- return charcode_error::input_underflow;
- return charcode_error::null;
- }
-
- charcode_error decode_wtranscode_length(code_seq<const char> &nseq, size_t *n,
- __mlibc_mbstate &st) override {
- __ensure(!st.__progress); // TODO: Update st with ds.progress() and ds.cpoint().
-
- code_seq<const char> decode_nseq = nseq;
- typename G::decode_state ds;
-
- *n = 0;
- while(decode_nseq) {
- // Consume the next code unit.
- if(auto e = ds(decode_nseq); e != charcode_error::null)
- return e;
-
- if(!ds.progress()) {
- nseq.it = decode_nseq.it;
- // "Commit" consumed code units (as there was no decode error).
- if(!ds.cpoint()) // Stop on null code points.
- return charcode_error::null;
- ++(*n);
- }
- }
-
- if(ds.progress())
- return charcode_error::input_underflow;
- return charcode_error::null;
- }
-
- charcode_error encode_wtranscode(code_seq<char> &nseq, code_seq<const wchar_t> &wseq,
- __mlibc_mbstate &st) override {
- __ensure(!st.__progress); // TODO: Update st with es.progress() and es.cpoint().
-
- code_seq<char> encode_nseq = nseq;
- typename G::encode_state es;
-
- while(encode_nseq && wseq) {
- codepoint cp = *wseq.it;
- if(!cp)
- return charcode_error::null;
-
- code_seq<const codepoint> cps{&cp, &cp + 1};
- if(auto e = es(encode_nseq, cps); e == charcode_error::dirty) {
- continue;
- }else if(e != charcode_error::null) {
- return e;
- }
- __ensure(cps.it == cps.end);
- ++wseq.it;
-
- // "Commit" produced code units (as there was no encode error).
- nseq.it = encode_nseq.it;
- }
-
- if(encode_nseq.it != nseq.it)
- return charcode_error::output_overflow;
- return charcode_error::null;
- }
-
- charcode_error encode_wtranscode_length(code_seq<const wchar_t> &wseq, size_t *n,
- __mlibc_mbstate &st) override {
- __ensure(!st.__progress); // TODO: Update st with es.progress() and es.cpoint().
-
- typename G::encode_state es;
-
- *n = 0;
- while(wseq) {
- char temp[4];
- code_seq<char> encode_nseq{temp, temp + 4};
- codepoint cp = *wseq.it;
- if(!cp)
- return charcode_error::null;
- // Consume the next code unit.
- code_seq<const codepoint> cps{&cp, &cp + 1};
- if(auto e = es(encode_nseq, cps); e == charcode_error::dirty) {
- continue;
- }else if(e != charcode_error::null) {
- return e;
- }
-
- ++(*n);
- ++wseq.it;
- }
-
- return charcode_error::null;
- }
-};
-
-polymorphic_charcode *current_charcode() {
- static polymorphic_charcode_adapter<utf8_charcode> global_charcode;
- return &global_charcode;
-}
-
-charcode_error wide_charcode::promote(wchar_t nc, codepoint &wc) {
- // TODO: Allow non-identity encodings of wchar_t.
- wc = nc;
- return charcode_error::null;
-}
-
-wide_charcode *platform_wide_charcode() {
- static wide_charcode global_wide_charcode;
- return &global_wide_charcode;
-}
-
-} // namespace mlibc
-
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