int lexer_unquoted_look_ahead_count(struct lexer_book *bk, char *char_set)
{
char c = -1;
int count = 0;
int double_quote = 0;
int single_quote = 0;
do
{
c = lexer_next_char(bk);
count++;
if( double_quote || single_quote )
{
if( c == '"' && double_quote )
double_quote = 0;
else if ( c == '\'' && single_quote )
single_quote = 0;
}
else if( strchr(char_set, c) )
{
break;
}
else if( c == '\\' )
{
lexer_next_char(bk);
count++;
}
else if( c == '"' )
{
double_quote = 1;
}
else if( c == '\'' )
{
single_quote = 1;
}
} while( c != '\n' && c != CHAR_EOF );
lexer_roll_back(bk, count);
if( c == CHAR_EOF )
{
if( strchr(char_set, CHAR_EOF) )
return count;
else
return -1;
}
else if( c == '\n' )
{
if( strchr(char_set, '\n') )
return count;
else
return -1;
}
else
return count;
}
accept_t lexer_read_variable(struct lexer_book * bk, struct token * name)
{
lexer_discard_white_space(bk);
if(lexer_next_peek(bk) == '=') {
lexer_next_char(bk);
lexer_add_to_lexeme(bk, '=');
} else {
int c = lexer_next_char(bk);
if(lexer_next_peek(bk) != '=')
return NO;
lexer_add_to_lexeme(bk, c);
lexer_next_char(bk); /* Jump = */
}
lexer_push_token(bk, lexer_pack_token(bk, VARIABLE));
lexer_push_token(bk, name);
lexer_discard_white_space(bk);
lexer_read_expandable(bk, '\n');
lexer_roll_back(bk, 1); //Recover '\n'
lexer_discard_white_space(bk);
if(lexer_next_char(bk) != '\n')
return NO;
return YES;
}
int lexer_read_variable(struct lexer *lx, struct token *name)
{
lexer_discard_white_space(lx);
if(lexer_next_peek(lx) == '=') {
lexer_next_char(lx);
lexer_add_to_lexeme(lx, '=');
} else {
int c = lexer_next_char(lx);
if(lexer_next_peek(lx) != '=')
lexer_report_error(lx, "Missing = in variable definition.");
lexer_add_to_lexeme(lx, c);
lexer_next_char(lx); /* Jump = */
}
lexer_push_token(lx, lexer_pack_token(lx, TOKEN_VARIABLE));
lexer_push_token(lx, name);
lexer_discard_white_space(lx);
//Read variable value
lexer_push_token(lx, lexer_read_expandable(lx, '\n'));
lexer_roll_back(lx, 1); //Recover '\n'
lexer_discard_white_space(lx);
if(lexer_next_char(lx) != '\n')
lexer_report_error(lx, "Missing newline at end of variable definition.");
return 1;
}
int lexer_next_peek(struct lexer_book *bk)
{
/* Read next chunk if necessary */
int c = lexer_next_char(bk);
lexer_roll_back(bk, 1);
return c;
}
int lexer_next_peek(struct lexer *lx)
{
/* Read next chunk if necessary */
int c = lexer_next_char(lx);
lexer_roll_back(lx, 1);
return c;
}
int lexer_peek_remote_rename_syntax(struct lexer_book *bk)
{
if(lexer_next_peek(bk) != '-')
return 0;
lexer_next_char(bk);
int is_gt = (lexer_next_peek(bk) == '>');
lexer_roll_back(bk, 1);
return is_gt;
}
int lexer_peek_remote_rename_syntax(struct lexer *lx)
{
if(lexer_next_peek(lx) != '-')
return 0;
lexer_next_char(lx);
int is_gt = (lexer_next_peek(lx) == '>');
lexer_roll_back(lx, 1);
return is_gt;
}
accept_t lexer_read_syntax(struct lexer_book * bk)
{
lexer_discard_white_space(bk);
struct token *name = lexer_read_syntax_name(bk);
if(strcmp("export", name->lexeme) == 0)
return lexer_read_syntax_export(bk, name);
else if(lexer_unquoted_look_ahead_count(bk, "=") > -1)
return lexer_read_variable(bk, name);
else {
lexer_roll_back(bk, strlen(name->lexeme));
lexer_report_error(bk, "Unrecognized keyword: %s.", name->lexeme);
}
return NO;
}
int lexer_read_syntax_or_variable(struct lexer * lx)
{
lexer_discard_white_space(lx);
struct token *name = lexer_read_syntax_name(lx);
if(strcmp("export", name->lexeme) == 0)
return lexer_read_syntax_export(lx, name);
else if(lexer_unquoted_look_ahead_count(lx, "=") > -1)
return lexer_read_variable(lx, name);
else {
lexer_roll_back(lx, strlen(name->lexeme));
lexer_report_error(lx, "Unrecognized keyword: %s.", name->lexeme);
}
return 1;
}
int lexer_read_variable_list(struct lexer * lx)
{
int c;
while((c = lexer_next_peek(lx)) != '\n') {
lexer_discard_white_space(lx);
if(c == '#') {
lexer_discard_comments(lx);
lexer_roll_back(lx, 1); //Recover the newline
break;
}
lexer_push_token(lx, lexer_read_syntax_name(lx));
}
lexer_add_to_lexeme(lx, lexer_next_char(lx)); //Drop the newline
lexer_push_token(lx, lexer_pack_token(lx, TOKEN_NEWLINE));
return 1;
}
accept_t lexer_read_variable_list(struct lexer_book * bk)
{
int c;
while((c = lexer_next_peek(bk)) != '\n') {
lexer_discard_white_space(bk);
if(c == '#') {
lexer_discard_comments(bk);
lexer_roll_back(bk, 1); //Recover the newline
break;
}
lexer_push_token(bk, lexer_read_syntax_name(bk));
}
lexer_add_to_lexeme(bk, lexer_next_char(bk)); //Drop the newline
lexer_push_token(bk, lexer_pack_token(bk, NEWLINE));
return YES;
}
