regs/docmaker/file.cc
2020-02-14 17:08:27 -07:00

118 lines
2.3 KiB
C++

/** @copyright 2020 Sean Kasun */
#include "file.h"
void File::skipWhitespace() {
while (p < end && isspace(*p)) {
if (*p == '\n') {
curLine++;
}
p++;
}
}
Token File::token() {
skipWhitespace();
prev = p;
Token t;
t.filename = name;
t.curLine = curLine;
if (p == end) {
t.type = END;
return t;
}
char ch = *p++;
if (isalpha(ch) || ch == '_') {
t.asStr += ch;
while (p < end && (isalnum(*p) || *p == '_')) {
t.asStr += *p++;
}
t.type = checkKeywords(t.asStr);
return t;
}
if (isdigit(ch) || ch == '-') {
bool isNeg = ch == '-';
if (isdigit(ch)) {
t.asNum = ch - '0';
}
while (p < end && isdigit(*p)) {
t.asNum *= 10;
t.asNum += *p++ - '0';
}
if (isNeg) {
t.asNum = -t.asNum;
}
t.type = NUMBER;
return t;
}
if (ch == '$') {
while (p < end && isxdigit(*p)) {
t.asNum <<= 4;
if (isdigit(*p)) {
t.asNum |= *p++ - '0';
} else if (*p >= 'a' && *p <= 'f') {
t.asNum |= *p++ - 'a' + 10;
} else {
t.asNum |= *p++ - 'A' + 10;
}
}
t.type = NUMBER;
return t;
}
t.type = SYMBOL;
t.asSym = ch;
return t;
}
void File::reset() {
p = prev;
}
TokenType File::checkKeywords(std::string keyword) {
if (keyword == "enum") {
return ENUM;
} else if (keyword == "struct") {
return STRUCT;
} else if (keyword == "union") {
return UNION;
}
return VAR;
}
bool Token::expect(char ch) {
if (type != SYMBOL) {
fprintf(stderr, "Error: %s:%d: ", filename.c_str(), curLine);
fprintf(stderr, "'%c' expected\n", ch);
return false;
}
if (asSym != ch) {
fprintf(stderr, "Error: %s:%d: ", filename.c_str(), curLine);
fprintf(stderr, "'%c' expected, found '%c' instead.\n", ch, asSym);
return false;
}
return true;
}
bool Token::expect(const char *str) {
if (type == SYMBOL) {
for (const char *s = str; *s; s++) {
if (*s == asSym) {
return true;
}
}
}
fprintf(stderr, "Error: %s:%d: ", filename.c_str(), curLine);
bool comma = false;
for (const char *s = str; *s; s++) {
fprintf(stderr, "%s'%c'", comma ? " or " : "", *s);
comma = true;
}
if (type == SYMBOL) {
fprintf(stderr, " expected, found '%c' instead\n", asSym);
} else {
fprintf(stderr, " expected\n");
}
return false;
}