int stdscan(void *private_data, struct tokenval *tv) { char ourcopy[MAX_KEYWORD + 1], *r, *s; (void)private_data; /* Don't warn that this parameter is unused */ stdscan_bufptr = nasm_skip_spaces(stdscan_bufptr); if (!*stdscan_bufptr) return tv->t_type = TOKEN_EOS; /* we have a token; either an id, a number or a char */ if (isidstart(*stdscan_bufptr) || (*stdscan_bufptr == '$' && isidstart(stdscan_bufptr[1]))) { /* now we've got an identifier */ bool is_sym = false; int token_type; if (*stdscan_bufptr == '$') { is_sym = true; stdscan_bufptr++; } r = stdscan_bufptr++; /* read the entire buffer to advance the buffer pointer but... */ while (isidchar(*stdscan_bufptr)) stdscan_bufptr++; /* ... copy only up to IDLEN_MAX-1 characters */ tv->t_charptr = stdscan_copy(r, stdscan_bufptr - r < IDLEN_MAX ? stdscan_bufptr - r : IDLEN_MAX - 1); if (is_sym || stdscan_bufptr - r > MAX_KEYWORD) return tv->t_type = TOKEN_ID; /* bypass all other checks */ for (s = tv->t_charptr, r = ourcopy; *s; s++) *r++ = nasm_tolower(*s); *r = '\0'; /* right, so we have an identifier sitting in temp storage. now, * is it actually a register or instruction name, or what? */ token_type = nasm_token_hash(ourcopy, tv); if (likely(!(tv->t_flag & TFLAG_BRC))) { /* most of the tokens fall into this case */ return token_type; } else { return tv->t_type = TOKEN_ID; } } else if (*stdscan_bufptr == '$' && !isnumchar(stdscan_bufptr[1])) { /* * It's a $ sign with no following hex number; this must * mean it's a Here token ($), evaluating to the current * assembly location, or a Base token ($$), evaluating to * the base of the current segment. */ stdscan_bufptr++; if (*stdscan_bufptr == '$') { stdscan_bufptr++; return tv->t_type = TOKEN_BASE; } return tv->t_type = TOKEN_HERE; } else if (isnumstart(*stdscan_bufptr)) { /* now we've got a number */ bool rn_error; bool is_hex = false; bool is_float = false; bool has_e = false; char c; r = stdscan_bufptr; if (*stdscan_bufptr == '$') { stdscan_bufptr++; is_hex = true; } for (;;) { c = *stdscan_bufptr++; if (!is_hex && (c == 'e' || c == 'E')) { has_e = true; if (*stdscan_bufptr == '+' || *stdscan_bufptr == '-') { /* * e can only be followed by +/- if it is either a * prefixed hex number or a floating-point number */ is_float = true; stdscan_bufptr++; } } else if (c == 'H' || c == 'h' || c == 'X' || c == 'x') { is_hex = true; } else if (c == 'P' || c == 'p') { is_float = true; if (*stdscan_bufptr == '+' || *stdscan_bufptr == '-') stdscan_bufptr++; } else if (isnumchar(c) || c == '_') ; /* just advance */ else if (c == '.') is_float = true; else break; } stdscan_bufptr--; /* Point to first character beyond number */ if (has_e && !is_hex) { /* 1e13 is floating-point, but 1e13h is not */ is_float = true; } if (is_float) { tv->t_charptr = stdscan_copy(r, stdscan_bufptr - r); return tv->t_type = TOKEN_FLOAT; } else { r = stdscan_copy(r, stdscan_bufptr - r); tv->t_integer = readnum(r, &rn_error); stdscan_pop(); if (rn_error) { /* some malformation occurred */ return tv->t_type = TOKEN_ERRNUM; } tv->t_charptr = NULL; return tv->t_type = TOKEN_NUM; } } else if (*stdscan_bufptr == '\'' || *stdscan_bufptr == '"' || *stdscan_bufptr == '`') { /* a quoted string */ char start_quote = *stdscan_bufptr; tv->t_charptr = stdscan_bufptr; tv->t_inttwo = nasm_unquote(tv->t_charptr, &stdscan_bufptr); if (*stdscan_bufptr != start_quote) return tv->t_type = TOKEN_ERRSTR; stdscan_bufptr++; /* Skip final quote */ return tv->t_type = TOKEN_STR; } else if (*stdscan_bufptr == '{') { /* now we've got a decorator */ int token_len; stdscan_bufptr = nasm_skip_spaces(stdscan_bufptr); r = ++stdscan_bufptr; /* * read the entire buffer to advance the buffer pointer * {rn-sae}, {rd-sae}, {ru-sae}, {rz-sae} contain '-' in tokens. */ while (isbrcchar(*stdscan_bufptr)) stdscan_bufptr++; token_len = stdscan_bufptr - r; /* ... copy only up to DECOLEN_MAX-1 characters */ tv->t_charptr = stdscan_copy(r, token_len < DECOLEN_MAX ? token_len : DECOLEN_MAX - 1); stdscan_bufptr = nasm_skip_spaces(stdscan_bufptr); /* if brace is not closed properly or token is too long */ if ((*stdscan_bufptr != '}') || (token_len > MAX_KEYWORD)) { nasm_error(ERR_NONFATAL, "invalid decorator token inside braces"); return tv->t_type = TOKEN_INVALID; } stdscan_bufptr++; /* skip closing brace */ for (s = tv->t_charptr, r = ourcopy; *s; s++) *r++ = nasm_tolower(*s); *r = '\0'; /* right, so we have a decorator sitting in temp storage. */ nasm_token_hash(ourcopy, tv); /* handle tokens inside braces */ return stdscan_handle_brace(tv); } else if (*stdscan_bufptr == ';') { /* a comment has happened - stay */ return tv->t_type = TOKEN_EOS; } else if (stdscan_bufptr[0] == '>' && stdscan_bufptr[1] == '>') { stdscan_bufptr += 2; return tv->t_type = TOKEN_SHR; } else if (stdscan_bufptr[0] == '<' && stdscan_bufptr[1] == '<') { stdscan_bufptr += 2; return tv->t_type = TOKEN_SHL; } else if (stdscan_bufptr[0] == '/' && stdscan_bufptr[1] == '/') { stdscan_bufptr += 2; return tv->t_type = TOKEN_SDIV; } else if (stdscan_bufptr[0] == '%' && stdscan_bufptr[1] == '%') { stdscan_bufptr += 2; return tv->t_type = TOKEN_SMOD; } else if (stdscan_bufptr[0] == '=' && stdscan_bufptr[1] == '=') { stdscan_bufptr += 2; return tv->t_type = TOKEN_EQ; } else if (stdscan_bufptr[0] == '<' && stdscan_bufptr[1] == '>') { stdscan_bufptr += 2; return tv->t_type = TOKEN_NE; } else if (stdscan_bufptr[0] == '!' && stdscan_bufptr[1] == '=') { stdscan_bufptr += 2; return tv->t_type = TOKEN_NE; } else if (stdscan_bufptr[0] == '<' && stdscan_bufptr[1] == '=') { stdscan_bufptr += 2; return tv->t_type = TOKEN_LE; } else if (stdscan_bufptr[0] == '>' && stdscan_bufptr[1] == '=') { stdscan_bufptr += 2; return tv->t_type = TOKEN_GE; } else if (stdscan_bufptr[0] == '&' && stdscan_bufptr[1] == '&') { stdscan_bufptr += 2; return tv->t_type = TOKEN_DBL_AND; } else if (stdscan_bufptr[0] == '^' && stdscan_bufptr[1] == '^') { stdscan_bufptr += 2; return tv->t_type = TOKEN_DBL_XOR; } else if (stdscan_bufptr[0] == '|' && stdscan_bufptr[1] == '|') { stdscan_bufptr += 2; return tv->t_type = TOKEN_DBL_OR; } else /* just an ordinary char */ return tv->t_type = (uint8_t)(*stdscan_bufptr++); }
std::string trans(const char str[]) /*将算术表达式转换成后追表达式*/ { ATLASSERT(strchr(str,' ')==nullptr); std::string exp; stack<char> op; char ch,lastch=0; ch=*str; /*将str的每一个数转换成ch*/ str++; while(ch) /*ch对应不同的符号的时候对应的转换情况*/ { if(isnumchar(lastch)==false && lastch!=')' && ch=='-') { op.push('p'); lastch=ch; } else if(ch=='(') { op.push(ch); lastch=ch; } else if(ch==')') { while(op.top()!='(') { exp+=op.top(); op.pop(); } op.pop(); lastch=ch; } else if(isoperator(ch)) { while(!op.empty() && op.top()!='(' && ispriority(op.top(),ch)) { exp+=op.top(); op.pop(); } op.push(ch); lastch=ch; } else { while(((lastch=='e' || lastch=='E') && ch=='-') || isnumchar(ch)) { exp+=ch; lastch=ch; ch=*str;str++; } str--; exp+='#'; } ch=*str; str++; } while(!op.empty()) { exp+=op.top(); op.pop(); } return exp; }