buzztok_t buzzlex_nexttok(buzzlex_t lex) {
buzzlex_file_t lexf = buzzlex_getfile(lex);
do {
/* Look for a non-space character */
do {
/* Keep reading until you find a non-space character or end of stream */
while(lexf->cur_c < lexf->buf_size &&
buzzlex_isspace(lexf->buf[lexf->cur_c])) {
nextchar();
}
/* End of stream? */
if(lexf->cur_c >= lexf->buf_size) {
/* Done with current file, go back to previous */
buzzdarray_pop(lex);
if(buzzdarray_isempty(lex))
/* No file to go back to, done parsing */
return NULL;
lexf = buzzlex_getfile(lex);
}
else
/* Non-space character found */
break;
} while(1);
/* Non-space character found */
/* If the current character is a '#' ignore the rest of the line */
if(lexf->buf[lexf->cur_c] == '#') {
do {
nextchar();
}
while(lexf->cur_c < lexf->buf_size &&
lexf->buf[lexf->cur_c] != '\n');
/* End of stream? */
if(lexf->cur_c >= lexf->buf_size) {
/* Done with current file, go back to previous */
buzzdarray_pop(lex);
if(buzzdarray_isempty(lex))
/* No file to go back to, done parsing */
return NULL;
lexf = buzzlex_getfile(lex);
}
else {
/* New line and carry on */
++lexf->cur_line;
lexf->cur_col = 0;
++lexf->cur_c;
}
}
else if(strncmp(lexf->buf + lexf->cur_c, "include", 7) == 0) {
/* Manage file inclusion */
lexf->cur_c += 7;
lexf->cur_col += 7;
/* Skip whitespace */
while(lexf->cur_c < lexf->buf_size &&
buzzlex_isspace(lexf->buf[lexf->cur_c])) {
nextchar();
}
/* End of file or not-string opening -> syntax error */
if(lexf->cur_c >= lexf->buf_size ||
!buzzlex_isquote(lexf->buf[lexf->cur_c])) {
fprintf(stderr,
"%s:%" PRIu64 ":%" PRIu64 ": Syntax error: expected string after include\n",
lexf->fname,
lexf->cur_line,
lexf->cur_col);
return NULL;
}
/* Read string */
char quote = lexf->buf[lexf->cur_c];
size_t start = lexf->cur_c + 1;
nextchar();
while(lexf->cur_c < lexf->buf_size &&
lexf->buf[lexf->cur_c] != quote &&
lexf->buf[lexf->cur_c] != '\n') {
nextchar();
}
/* End of file or newline -> syntax error */
if(lexf->cur_c >= lexf->buf_size ||
lexf->buf[lexf->cur_c] == '\n') {
fprintf(stderr,
"%s:%" PRIu64 ":%" PRIu64 ": Syntax error: expected end of string\n",
lexf->fname,
lexf->cur_line,
lexf->cur_col);
return NULL;
}
/* Copy data into a new string */
char* fname = (char*)malloc(lexf->cur_c - start + 1);
strncpy(fname, lexf->buf + start, lexf->cur_c - start);
fname[lexf->cur_c - start] = '\0';
/* Get to next character in this file */
nextchar();
/* Create new file structure */
buzzlex_file_t f = buzzlex_file_new(fname);
if(!f) {
fprintf(stderr,
"%s:%" PRIu64 ":%" PRIu64 ": Can't read '%s'\n",
lexf->fname,
lexf->cur_line,
lexf->cur_col,
fname);
free(fname);
return NULL;
}
free(fname);
/* Make sure the file hasn't been already included */
if(buzzdarray_find(lex, buzzlex_file_cmp, &f) < buzzdarray_size(lex)) {
buzzlex_file_destroy(0, &f, NULL);
}
else {
/* Push file structure */
buzzdarray_push(lex, &f);
lexf = buzzlex_getfile(lex);
}
}
else
/* The character must be parsed */
break;
}
while(1);
/* If we get here it's because we read potential token character */
uint64_t tokstart = lexf->cur_col - 1;
char c = lexf->buf[lexf->cur_c];
nextchar();
/* Consider the 1-char non-alphanumeric cases first */
switch(c) {
case '\n': {
buzztok_t tok = buzzlex_newtok(BUZZTOK_STATEND,
NULL,
lexf->cur_line,
tokstart,
lexf->fname);
++lexf->cur_line;
lexf->cur_col = 0;
return tok;
}
casetokchar(';', BUZZTOK_STATEND);
casetokchar('{', BUZZTOK_BLOCKOPEN);
casetokchar('}', BUZZTOK_BLOCKCLOSE);
casetokchar('(', BUZZTOK_PAROPEN);
casetokchar(')', BUZZTOK_PARCLOSE);
casetokchar('[', BUZZTOK_IDXOPEN);
casetokchar(']', BUZZTOK_IDXCLOSE);
casetokchar(',', BUZZTOK_LISTSEP);
casetokchar('.', BUZZTOK_DOT);
}
/* If we get here, it's because we found either a constant, an
* identifier, a keyword, an assignment, a comparison operator,
* an arithmetic operator, or an unexpected character */
if(isdigit(c)) {
/* It's a constant */
readval(buzzlex_isnumber);
return buzzlex_newtok(BUZZTOK_CONST,
val,
lexf->cur_line,
tokstart,
lexf->fname);
}
else if(isalpha(c)) {
/* It's either a keyword or an identifier */
readval(buzzlex_isid);
/* Go through the possible keywords */
checkkeyword("var", BUZZTOK_VAR);
checkkeyword("if", BUZZTOK_IF);
checkkeyword("else", BUZZTOK_ELSE);
checkkeyword("function", BUZZTOK_FUN);
checkkeyword("return", BUZZTOK_RETURN);
checkkeyword("for", BUZZTOK_FOR);
checkkeyword("while", BUZZTOK_WHILE);
checkkeyword("and", BUZZTOK_ANDOR);
checkkeyword("or", BUZZTOK_ANDOR);
checkkeyword("not", BUZZTOK_NOT);
checkkeyword("nil", BUZZTOK_NIL);
/* No keyword found, consider it an id */
return buzzlex_newtok(BUZZTOK_ID,
val,
lexf->cur_line,
tokstart,
lexf->fname);
}
else if(c == '=') {
/* Either an assignment or a comparison */
if(lexf->cur_c < lexf->buf_size &&
lexf->buf[lexf->cur_c] == '=') {
/* It's a comparison */
nextchar();
return buzzlex_newtok(BUZZTOK_CMP,
strdup("=="),
lexf->cur_line,
tokstart,
lexf->fname);
}
else {
/* It's an assignment */
return buzzlex_newtok(BUZZTOK_ASSIGN,
NULL,
lexf->cur_line,
tokstart,
lexf->fname);
}
}
else if(c == '!') {
/* Comparison operator? */
if(lexf->cur_c < lexf->buf_size &&
lexf->buf[lexf->cur_c] == '=') {
/* It's a comparison */
nextchar();
return buzzlex_newtok(BUZZTOK_CMP,
strdup("!="),
lexf->cur_line,
tokstart,
lexf->fname);
}
else {
/* Syntax error */
fprintf(stderr,
"%s:%" PRIu64 ":%" PRIu64 ": Syntax error: expected '=' after '!'\n",
lexf->fname,
lexf->cur_line,
tokstart);
return NULL;
}
}
else if((c == '<') || (c == '>')) {
/* It's a comparison operator */
size_t start = lexf->cur_c - 1;
/* Include the '=' if present */
if(lexf->cur_c < lexf->buf_size &&
lexf->buf[lexf->cur_c] == '=') {
nextchar();
}
char* val = (char*)malloc(lexf->cur_c - start + 1);
strncpy(val, lexf->buf + start, lexf->cur_c - start);
val[lexf->cur_c - start] = 0;
return buzzlex_newtok(BUZZTOK_CMP,
val,
lexf->cur_line,
tokstart,
lexf->fname);
}
else if(buzzlex_isarith(c)) {
/* Arithmetic operator */
char* val = (char*)malloc(2);
strncpy(val, lexf->buf + lexf->cur_c - 1, 1);
val[1] = 0;
switch(c) {
case '+': case '-': {
return buzzlex_newtok(BUZZTOK_ADDSUB,
val,
lexf->cur_line,
tokstart,
lexf->fname);
}
case '*': case '/': {
return buzzlex_newtok(BUZZTOK_MULDIV,
val,
lexf->cur_line,
tokstart,
lexf->fname);
}
case '%': {
return buzzlex_newtok(BUZZTOK_MOD,
val,
lexf->cur_line,
tokstart,
lexf->fname);
}
case '^': {
return buzzlex_newtok(BUZZTOK_POW,
val,
lexf->cur_line,
tokstart,
lexf->fname);
}
default:
return NULL;
}
}
else if(buzzlex_isquote(c)) {
/* String - eat any character until you find the next matching quote */
size_t start = lexf->cur_c;
char last1 = 0, last2 = 0;
while(lexf->cur_c < lexf->buf_size && /* Not end of stream */
((lexf->buf[lexf->cur_c] != c) || /* Matching quote not found */
(lexf->buf[lexf->cur_c] == c && /* Matching quote found, but preceded by \ and not \\ */
last1 == '\\' && last2 != '\\'))) {
/* Remember the last two characters read */
last2 = last1;
last1 = lexf->buf[lexf->cur_c];
/* Keep parsing the string */
if(lexf->buf[lexf->cur_c] != '\n') {
nextchar();
}
else {
fprintf(stderr,
"%s:%" PRIu64 ":%" PRIu64 ": Syntax error: string closing quote not found\n",
lexf->fname,
lexf->cur_line,
tokstart);
return NULL;
}
}
/* End of stream? Syntax error */
if(lexf->cur_c >= lexf->buf_size) {
fprintf(stderr,
"%s:%" PRIu64 ":%" PRIu64 ": Syntax error: string closing quote not found\n",
lexf->fname,
lexf->cur_line,
tokstart);
return NULL;
}
/* We have a valid string */
char* val = buzzlex_newstring(lexf->buf + start,
lexf->cur_c - start);
nextchar();
return buzzlex_newtok(BUZZTOK_STRING,
val,
lexf->cur_line,
tokstart,
lexf->fname);
}
else {
/* Unknown character */
fprintf(stderr,
"%s:%" PRIu64 ":%" PRIu64 ": Syntax error: unknown character '%c' (octal: %o; hex: %x)\n",
lexf->fname,
lexf->cur_line,
tokstart,
c, c, c);
return NULL;
}
}
buzztok_t buzzlex_nexttok(buzzlex_t lex) {
do {
/* Keep reading until you find a non-space character or end of stream */
while(lex->cur_c < lex->buf_size &&
buzzlex_isspace(lex->buf[lex->cur_c])) {
nextchar();
}
/* End of stream? No token */
if(lex->cur_c >= lex->buf_size) return NULL;
/* If the current character is a '#' ignore the rest of the line */
if(lex->buf[lex->cur_c] == '#') {
do {
nextchar();
}
while(lex->cur_c < lex->buf_size &&
lex->buf[lex->cur_c] != '\n');
/* End of stream? No token */
if(lex->cur_c >= lex->buf_size) return NULL;
/* New line and carry on */
++lex->cur_line;
lex->cur_col = 0;
++lex->cur_c;
}
else {
/* The current character must be parsed */
break;
}
}
while(1);
/* If we get here it's because we read a non-space character */
char c = lex->buf[lex->cur_c];
nextchar();
/* Consider the 1-char non-alphanumeric cases first */
switch(c) {
case '\n': {
buzztok_t tok = buzzlex_newtok(BUZZTOK_STATEND,
NULL,
lex->cur_line,
lex->cur_col);
++lex->cur_line;
lex->cur_col = 0;
return tok;
}
casetokchar(';', BUZZTOK_STATEND);
casetokchar('{', BUZZTOK_BLOCKOPEN);
casetokchar('}', BUZZTOK_BLOCKCLOSE);
casetokchar('(', BUZZTOK_PAROPEN);
casetokchar(')', BUZZTOK_PARCLOSE);
casetokchar('[', BUZZTOK_IDXOPEN);
casetokchar(']', BUZZTOK_IDXCLOSE);
casetokchar(',', BUZZTOK_LISTSEP);
casetokchar('.', BUZZTOK_DOT);
}
/* If we get here, it's because we found either a constant, an
* identifier, a keyword, an assignment, a comparison operator,
* an arithmetic operator, or an unexpected character */
if(isdigit(c)) {
/* It's a constant */
readval(buzzlex_isnumber);
return buzzlex_newtok(BUZZTOK_CONST,
val,
lex->cur_line,
lex->cur_col);
}
else if(isalpha(c)) {
/* It's either a keyword or an identifier */
readval(buzzlex_isid);
/* Go through the possible keywords */
checkkeyword("var", BUZZTOK_VAR);
checkkeyword("if", BUZZTOK_IF);
checkkeyword("else", BUZZTOK_ELSE);
checkkeyword("function", BUZZTOK_FUN);
checkkeyword("return", BUZZTOK_RETURN);
checkkeyword("for", BUZZTOK_FOR);
checkkeyword("while", BUZZTOK_WHILE);
checkkeyword("and", BUZZTOK_ANDOR);
checkkeyword("or", BUZZTOK_ANDOR);
checkkeyword("not", BUZZTOK_NOT);
checkkeyword("nil", BUZZTOK_NIL);
/* No keyword found, consider it an id */
return buzzlex_newtok(BUZZTOK_ID,
val,
lex->cur_line,
lex->cur_col);
}
else if(c == '=') {
/* Either an assignment or a comparison */
if(lex->cur_c < lex->buf_size &&
lex->buf[lex->cur_c] == '=') {
/* It's a comparison */
nextchar();
return buzzlex_newtok(BUZZTOK_CMP,
strdup("=="),
lex->cur_line,
lex->cur_col);
}
else {
/* It's an assignment */
return buzzlex_newtok(BUZZTOK_ASSIGN,
NULL,
lex->cur_line,
lex->cur_col);
}
}
else if(c == '!') {
/* Comparison operator? */
if(lex->cur_c < lex->buf_size &&
lex->buf[lex->cur_c] == '=') {
/* It's a comparison */
nextchar();
return buzzlex_newtok(BUZZTOK_CMP,
strdup("!="),
lex->cur_line,
lex->cur_col);
}
else {
/* Syntax error */
fprintf(stderr,
"%s:%llu:%llu: Syntax error: expected '=' after '!'\n",
lex->fname,
lex->cur_line,
lex->cur_col);
return NULL;
}
}
else if((c == '<') || (c == '>')) {
/* It's a comparison operator */
size_t start = lex->cur_c - 1;
/* Include the '=' if present */
if(lex->cur_c < lex->buf_size &&
lex->buf[lex->cur_c] == '=') {
nextchar();
}
char* val = (char*)malloc(lex->cur_c - start + 1);
strncpy(val, lex->buf + start, lex->cur_c - start);
val[lex->cur_c - start] = 0;
return buzzlex_newtok(BUZZTOK_CMP,
val,
lex->cur_line,
lex->cur_col);
}
else if(buzzlex_isarith(c)) {
/* Arithmetic operator */
char* val = (char*)malloc(2);
strncpy(val, lex->buf + lex->cur_c - 1, 1);
val[1] = 0;
switch(c) {
case '+': case '-': {
return buzzlex_newtok(BUZZTOK_ADDSUB,
val,
lex->cur_line,
lex->cur_col);
}
case '*': case '/': {
return buzzlex_newtok(BUZZTOK_MULDIV,
val,
lex->cur_line,
lex->cur_col);
}
case '%': {
return buzzlex_newtok(BUZZTOK_MOD,
val,
lex->cur_line,
lex->cur_col);
}
case '^': {
return buzzlex_newtok(BUZZTOK_POW,
val,
lex->cur_line,
lex->cur_col);
}
default:
return NULL;
}
}
else if(buzzlex_isquote(c)) {
/* String - eat any character until you find the next matching quote */
size_t start = lex->cur_c;
while(lex->cur_c < lex->buf_size &&
lex->buf[lex->cur_c] != c) {
if(lex->buf[lex->cur_c] != '\n') {
nextchar();
}
else {
++lex->cur_line;
lex->cur_col = 0;
++lex->cur_c;
}
}
/* End of stream? Syntax error */
if(lex->cur_c >= lex->buf_size) {
fprintf(stderr,
"%s:%llu:%llu: Syntax error: string closing quote not found\n",
lex->fname,
lex->cur_line,
lex->cur_col);
return NULL;
}
/* Valid string */
char* val = (char*)malloc(lex->cur_c - start + 1);
strncpy(val, lex->buf + start, lex->cur_c - start);
val[lex->cur_c - start] = '\0';
nextchar();
return buzzlex_newtok(BUZZTOK_STRING,
val,
lex->cur_line,
lex->cur_col);
}
else {
/* Unknown character */
fprintf(stderr,
"%s:%llu:%llu: Syntax error: unknown character '%c' (octal: %o; hex: %x)\n",
lex->fname,
lex->cur_line,
lex->cur_col,
c, c, c);
return NULL;
}
}
