/**
* Client-side C syntax highlighter for RDoc */
(function() {
'use strict';
// C control flow and storage class keywords
const C_KEYWORDS = new Set([
'auto', 'break', 'case', 'continue', 'default', 'do', 'else', 'extern',
'for', 'goto', 'if', 'inline', 'register', 'return', 'sizeof', 'static',
'switch', 'while',
'_Alignas', '_Alignof', '_Generic', '_Noreturn', '_Static_assert', '_Thread_local'
]);
// C type keywords and type qualifiers
const C_TYPE_KEYWORDS = new Set([
'bool', 'char', 'const', 'double', 'enum', 'float', 'int', 'long',
'restrict', 'short', 'signed', 'struct', 'typedef', 'union', 'unsigned',
'void', 'volatile', '_Atomic', '_Bool', '_Complex', '_Imaginary'
]);
// Library-defined types (typedef'd in headers, not language keywords)
// Includes: Ruby C API types (VALUE, ID), POSIX types (size_t, ssize_t),
// fixed-width integer types (uint32_t, int64_t), and standard I/O types (FILE)
const C_TYPES = new Set([
'VALUE', 'ID', 'size_t', 'ssize_t', 'ptrdiff_t', 'uintptr_t', 'intptr_t',
'uint8_t', 'uint16_t', 'uint32_t', 'uint64_t',
'int8_t', 'int16_t', 'int32_t', 'int64_t',
'FILE', 'DIR', 'va_list'
]);
// Common Ruby VALUE macros and boolean literals
const RUBY_MACROS = new Set([
'Qtrue', 'Qfalse', 'Qnil', 'Qundef', 'NULL', 'TRUE', 'FALSE', 'true', 'false'
]);
const OPERATORS = new Set([
'==', '!=', '<=', '>=', '&&', '||', '<<', '>>', '++', '--',
'+=', '-=', '*=', '/=', '%=', '&=', '|=', '^=', '->',
'+', '-', '*', '/', '%', '<', '>', '=', '!', '&', '|', '^', '~'
]);
// Single character that can start an operator
const OPERATOR_CHARS = new Set('+-*/%<>=!&|^~');
function isMacro(word) {
return RUBY_MACROS.has(word) || /^[A-Z][A-Z0-9_]*$/.test(word);
}
function isType(word) {
return C_TYPE_KEYWORDS.has(word) || C_TYPES.has(word) || /_t$/.test(word);
}
/**
* Escape HTML special characters
*/
function escapeHtml(text) {
return text
.replace(/&/g, '&')
.replace(/</g, '<')
.replace(/>/g, '>')
.replace(/"/g, '"')
.replace(/'/g, ''');
}
/**
* Check if position is at line start (only whitespace before it)
*/
function isLineStart(code, pos) {
if (pos === 0) return true;
for (let i = pos - 1; i >= 0; i--) {
const ch = code[i];
if (ch === '\n') return true;
if (ch !== ' ' && ch !== '\t') return false;
}
return true;
}
/**
* Highlight C source code
*/
function highlightC(code) {
const tokens = [];
let i = 0;
const len = code.length;
while (i < len) {
const char = code[i];
// Multi-line comment
if (char === '/' && code[i + 1] === '*') {
let end = code.indexOf('*/', i + 2);
end = (end === -1) ? len : end + 2;
const comment = code.substring(i, end);
tokens.push('<span class="c-comment">', escapeHtml(comment), '</span>');
i = end;
continue;
}
// Single-line comment
if (char === '/' && code[i + 1] === '/') {
const end = code.indexOf('\n', i);
const commentEnd = (end === -1) ? len : end;
const comment = code.substring(i, commentEnd);
tokens.push('<span class="c-comment">', escapeHtml(comment), '</span>');
i = commentEnd;
continue;
}
// Preprocessor directive (must be at line start)
if (char === '#' && isLineStart(code, i)) {
let end = i + 1;
while (end < len && code[end] !== '\n') {
if (code[end] === '\\' && end + 1 < len && code[end + 1] === '\n') {
end += 2; // Handle line continuation
} else {
end++;
}
}
const preprocessor = code.substring(i, end);
tokens.push('<span class="c-preprocessor">', escapeHtml(preprocessor), '</span>');
i = end;
continue;
}
// String literal
if (char === '"') {
let end = i + 1;
while (end < len && code[end] !== '"') {
if (code[end] === '\\' && end + 1 < len) {
end += 2; // Skip escaped character
} else {
end++;
}
}
if (end < len) end++; // Include closing quote
const string = code.substring(i, end);
tokens.push('<span class="c-string">', escapeHtml(string), '</span>');
i = end;
continue;
}
// Character literal
if (char === "'") {
let end = i + 1;
// Handle escape sequences like '\n', '\\', '\''
if (end < len && code[end] === '\\' && end + 1 < len) {
end += 2; // Skip backslash and escaped char
} else if (end < len) {
end++; // Single character
}
if (end < len && code[end] === "'") end++; // Closing quote
const charLit = code.substring(i, end);
tokens.push('<span class="c-value">', escapeHtml(charLit), '</span>');
i = end;
continue;
}
// Number (integer or float)
if (char >= '0' && char <= '9') {
let end = i;
// Hexadecimal
if (char === '0' && (code[i + 1] === 'x' || code[i + 1] === 'X')) {
end = i + 2;
while (end < len) {
const ch = code[end];
if ((ch >= '0' && ch <= '9') || (ch >= 'a' && ch <= 'f') || (ch >= 'A' && ch <= 'F')) {
end++;
} else {
break;
}
}
}
// Octal
else if (char === '0' && code[i + 1] >= '0' && code[i + 1] <= '7') {
end = i + 1;
while (end < len && code[end] >= '0' && code[end] <= '7') end++;
}
// Decimal/Float
else {
while (end < len) {
const ch = code[end];
if ((ch >= '0' && ch <= '9') || ch === '.') {
end++;
} else {
break;
}
}
// Scientific notation
if (end < len && (code[end] === 'e' || code[end] === 'E')) {
end++;
if (end < len && (code[end] === '+' || code[end] === '-')) end++;
while (end < len && code[end] >= '0' && code[end] <= '9') end++;
}
}
// Suffix (u, l, f, etc.)
while (end < len) {
const ch = code[end];
if (ch === 'u' || ch === 'U' || ch === 'l' || ch === 'L' || ch === 'f' || ch === 'F') {
end++;
} else {
break;
}
}
const number = code.substring(i, end);
tokens.push('<span class="c-value">', escapeHtml(number), '</span>');
i = end;
continue;
}
// Identifier or keyword
if ((char >= 'a' && char <= 'z') || (char >= 'A' && char <= 'Z') || char === '_') {
let end = i + 1;
while (end < len) {
const ch = code[end];
if ((ch >= 'a' && ch <= 'z') || (ch >= 'A' && ch <= 'Z') ||
(ch >= '0' && ch <= '9') || ch === '_') {
end++;
} else {
break;
}
}
const word = code.substring(i, end);
if (C_KEYWORDS.has(word)) {
tokens.push('<span class="c-keyword">', escapeHtml(word), '</span>');
} else if (isType(word)) {
// Check types before macros (VALUE, ID are types, not macros)
tokens.push('<span class="c-type">', escapeHtml(word), '</span>');
} else if (isMacro(word)) {
tokens.push('<span class="c-macro">', escapeHtml(word), '</span>');
} else {
// Check if followed by '(' -> function name
let nextCharIdx = end;
while (nextCharIdx < len && (code[nextCharIdx] === ' ' || code[nextCharIdx] === '\t')) {
nextCharIdx++;
}
if (nextCharIdx < len && code[nextCharIdx] === '(') {
tokens.push('<span class="c-function">', escapeHtml(word), '</span>');
} else {
tokens.push('<span class="c-identifier">', escapeHtml(word), '</span>');
}
}
i = end;
continue;
}
// Operators
if (OPERATOR_CHARS.has(char)) {
let op = char;
// Check for two-character operators
if (i + 1 < len) {
const twoChar = char + code[i + 1];
if (OPERATORS.has(twoChar)) {
op = twoChar;
}
}
tokens.push('<span class="c-operator">', escapeHtml(op), '</span>');
i += op.length;
continue;
}
// Everything else (punctuation, whitespace)
tokens.push(escapeHtml(char));
i++;
}
return tokens.join('');
}
/**
* Initialize C syntax highlighting on page load
*/
function initHighlighting() {
const codeBlocks = document.querySelectorAll('pre.c');
codeBlocks.forEach(block => {
if (block.getAttribute('data-highlighted') === 'true') {
return;
}
const code = block.textContent;
const highlighted = highlightC(code);
block.innerHTML = highlighted;
block.setAttribute('data-highlighted', 'true');
});
}
if (document.readyState === 'loading') {
document.addEventListener('DOMContentLoaded', initHighlighting);
} else {
initHighlighting();
}
})();