From 1fdd0b8dc8f2895c5942b23410f11ea21dd4e3f4 Mon Sep 17 00:00:00 2001 From: Neil Date: Thu, 10 Jun 2021 16:03:47 +1000 Subject: Use string_view for PositionCache methods. Replace custom hash code with standard library hash. Drop standard methods that are not needed. Restrict representations to 200 bytes. Improve documentation. --- doc/ScintillaDoc.html | 8 ++++--- src/EditView.cxx | 7 +++--- src/PositionCache.cxx | 63 ++++++++++++++++++++++----------------------------- src/PositionCache.h | 17 +++++--------- 4 files changed, 42 insertions(+), 53 deletions(-) diff --git a/doc/ScintillaDoc.html b/doc/ScintillaDoc.html index 300ae0208..d972c99a7 100644 --- a/doc/ScintillaDoc.html +++ b/doc/ScintillaDoc.html @@ -3861,20 +3861,22 @@ struct Sci_TextToFind { SCI_GETREPRESENTATION(const char *encodedCharacter, char *representation NUL-terminated) → int
SCI_CLEARREPRESENTATION(const char *encodedCharacter)
Any character, including those normally displayed as mnemonics may be represented by a - string inverted in a rounded rectangle.

+ Unicode string inverted in a rounded rectangle.

For example, the Ohm sign Ω U+2126 looks very similar to the Greek Omega character Ω U+03C9 so, for the UTF-8 encoding, to distinguish the Ohm sign as "U+2126 Ω" this call could be made: SCI_SETREPRESENTATION("\xe2\x84\xa6", "U+2126 \xe2\x84\xa6")

-

The encodedCharacter parameter is a NUL-terminated string of the bytes for one character in the +

The encodedCharacter parameter is a NUL-terminated string of the bytes for one character in the current encoding. This can not be used to set a representation for multiple-character strings.

+

The representation parameter is a NUL-terminated UTF-8 string with a maximum length of 200 bytes.

+

One exception to the single character restriction is that the two character sequence "\r\n" (Carriage Return + Line Feed) can have a representation that is visible in line end viewing (SCI_SETVIEWEOL) mode. If there is no representation for "\r\n" then the individual '\r' and '\n' representations will be seen.

-

The NUL (0) character is a special case since the encodedCharacter parameter is NUL terminated, the NUL +

The NUL (0) character is a special case since the encodedCharacter parameter is NUL terminated, the NUL character is specified as an empty string.

SCI_CLEARALLREPRESENTATIONS
diff --git a/src/EditView.cxx b/src/EditView.cxx index 5d69c1345..92c1450cc 100644 --- a/src/EditView.cxx +++ b/src/EditView.cxx @@ -473,7 +473,8 @@ void EditView::LayoutLine(const EditModel &model, Surface *surface, const ViewSt representationWidth = NextTabstopPos(line, x, vstyle.tabWidth) - ll->positions[ts.start]; } else { if (representationWidth <= 0.0) { - XYPOSITION positionsRepr[256]; // Should expand when needed + assert(ts.representation->stringRep.length() <= Representation::maxLength); + XYPOSITION positionsRepr[Representation::maxLength+1]; surface->MeasureWidthsUTF8(vstyle.styles[StyleControlChar].font.get(), ts.representation->stringRep, positionsRepr); representationWidth = positionsRepr[ts.representation->stringRep.length() - 1]; if (FlagSet(ts.representation->appearance, RepresentationAppearance::Blob)) { @@ -488,8 +489,8 @@ void EditView::LayoutLine(const EditModel &model, Surface *surface, const ViewSt // Over half the segments are single characters and of these about half are space characters. ll->positions[ts.start + 1] = vstyle.styles[ll->styles[ts.start]].spaceWidth; } else { - posCache.MeasureWidths(surface, vstyle, ll->styles[ts.start], &ll->chars[ts.start], - ts.length, &ll->positions[ts.start + 1]); + posCache.MeasureWidths(surface, vstyle, ll->styles[ts.start], + std::string_view(&ll->chars[ts.start], ts.length), &ll->positions[ts.start + 1]); } } lastSegItalics = (!ts.representation) && ((ll->chars[ts.end() - 1] != ' ') && vstyle.styles[ll->styles[ts.start]].italic); diff --git a/src/PositionCache.cxx b/src/PositionCache.cxx index 7ea3055d4..d3347248b 100644 --- a/src/PositionCache.cxx +++ b/src/PositionCache.cxx @@ -546,7 +546,7 @@ static unsigned int KeyFromString(std::string_view charBytes) noexcept { } void SpecialRepresentations::SetRepresentation(std::string_view charBytes, std::string_view value) { - if (charBytes.length() <= 4) { + if ((charBytes.length() <= 4) && (value.length() <= Representation::maxLength)) { const unsigned int key = KeyFromString(charBytes); MapRepresentation::iterator it = mapReprs.find(key); if (it == mapReprs.end()) { @@ -754,12 +754,12 @@ bool BreakFinder::More() const noexcept { } PositionCacheEntry::PositionCacheEntry() noexcept : - styleNumber(0), len(0), clock(0), positions(nullptr) { + styleNumber(0), len(0), clock(0) { } // Copy constructor not currently used, but needed for being element in std::vector. PositionCacheEntry::PositionCacheEntry(const PositionCacheEntry &other) : - styleNumber(other.styleNumber), len(other.styleNumber), clock(other.styleNumber), positions(nullptr) { + styleNumber(other.styleNumber), len(other.len), clock(other.clock) { if (other.positions) { const size_t lenData = len + (len / sizeof(XYPOSITION)) + 1; positions = std::make_unique(lenData); @@ -767,18 +767,18 @@ PositionCacheEntry::PositionCacheEntry(const PositionCacheEntry &other) : } } -void PositionCacheEntry::Set(unsigned int styleNumber_, const char *s_, - unsigned int len_, const XYPOSITION *positions_, unsigned int clock_) { +void PositionCacheEntry::Set(unsigned int styleNumber_, std::string_view sv, + const XYPOSITION *positions_, unsigned int clock_) { Clear(); styleNumber = styleNumber_; - len = len_; + len = static_cast(sv.length()); clock = clock_; - if (s_ && positions_) { + if (sv.data() && positions_) { positions = std::make_unique(len + (len / sizeof(XYPOSITION)) + 1); for (unsigned int i=0; i{}(sv); + const size_t h2 = std::hash{}(styleNumber_); + return h1 ^ (h2 << 1); } bool PositionCacheEntry::NewerThan(const PositionCacheEntry &other) const noexcept { @@ -835,10 +827,6 @@ PositionCache::PositionCache() { allClear = true; } -PositionCache::~PositionCache() { - Clear(); -} - void PositionCache::Clear() noexcept { if (!allClear) { for (PositionCacheEntry &pce : pces) { @@ -854,23 +842,26 @@ void PositionCache::SetSize(size_t size_) { pces.resize(size_); } -void PositionCache::MeasureWidths(Surface *surface, const ViewStyle &vstyle, unsigned int styleNumber, - const char *s, unsigned int len, XYPOSITION *positions) { +size_t PositionCache::GetSize() const noexcept { + return pces.size(); +} +void PositionCache::MeasureWidths(Surface *surface, const ViewStyle &vstyle, unsigned int styleNumber, + std::string_view sv, XYPOSITION *positions) { allClear = false; size_t probe = pces.size(); // Out of bounds - if ((!pces.empty()) && (len < 30)) { + if ((!pces.empty()) && (sv.length() < 30)) { // Only store short strings in the cache so it doesn't churn with // long comments with only a single comment. // Two way associative: try two probe positions. - const unsigned int hashValue = PositionCacheEntry::Hash(styleNumber, s, len); + const size_t hashValue = PositionCacheEntry::Hash(styleNumber, sv); probe = hashValue % pces.size(); - if (pces[probe].Retrieve(styleNumber, s, len, positions)) { + if (pces[probe].Retrieve(styleNumber, sv, positions)) { return; } - const unsigned int probe2 = (hashValue * 37) % pces.size(); - if (pces[probe2].Retrieve(styleNumber, s, len, positions)) { + const size_t probe2 = (hashValue * 37) % pces.size(); + if (pces[probe2].Retrieve(styleNumber, sv, positions)) { return; } // Not found. Choose the oldest of the two slots to replace @@ -879,7 +870,7 @@ void PositionCache::MeasureWidths(Surface *surface, const ViewStyle &vstyle, uns } } const Font *fontStyle = vstyle.styles[styleNumber].font.get(); - surface->MeasureWidths(fontStyle, std::string_view(s, len), positions); + surface->MeasureWidths(fontStyle, sv, positions); if (probe < pces.size()) { // Store into cache clock++; @@ -891,6 +882,6 @@ void PositionCache::MeasureWidths(Surface *surface, const ViewStyle &vstyle, uns } clock = 2; } - pces[probe].Set(styleNumber, s, len, positions, clock); + pces[probe].Set(styleNumber, sv, positions, clock); } } diff --git a/src/PositionCache.h b/src/PositionCache.h index 030b16504..b628b0421 100644 --- a/src/PositionCache.h +++ b/src/PositionCache.h @@ -188,16 +188,17 @@ public: void operator=(const PositionCacheEntry &) = delete; void operator=(PositionCacheEntry &&) = delete; ~PositionCacheEntry(); - void Set(unsigned int styleNumber_, const char *s_, unsigned int len_, const XYPOSITION *positions_, unsigned int clock_); + void Set(unsigned int styleNumber_, std::string_view sv, const XYPOSITION *positions_, unsigned int clock_); void Clear() noexcept; - bool Retrieve(unsigned int styleNumber_, const char *s_, unsigned int len_, XYPOSITION *positions_) const noexcept; - static unsigned int Hash(unsigned int styleNumber_, const char *s, unsigned int len_) noexcept; + bool Retrieve(unsigned int styleNumber_, std::string_view sv, XYPOSITION *positions_) const noexcept; + static size_t Hash(unsigned int styleNumber_, std::string_view sv) noexcept; bool NewerThan(const PositionCacheEntry &other) const noexcept; void ResetClock() noexcept; }; class Representation { public: + static constexpr size_t maxLength = 200; std::string stringRep; RepresentationAppearance appearance; ColourRGBA colour; @@ -271,17 +272,11 @@ class PositionCache { bool allClear; public: PositionCache(); - // Deleted so PositionCache objects can not be copied. - PositionCache(const PositionCache &) = delete; - PositionCache(PositionCache &&) = delete; - void operator=(const PositionCache &) = delete; - void operator=(PositionCache &&) = delete; - ~PositionCache(); void Clear() noexcept; void SetSize(size_t size_); - size_t GetSize() const noexcept { return pces.size(); } + size_t GetSize() const noexcept; void MeasureWidths(Surface *surface, const ViewStyle &vstyle, unsigned int styleNumber, - const char *s, unsigned int len, XYPOSITION *positions); + std::string_view sv, XYPOSITION *positions); }; } -- cgit v1.2.3