ledger/src/token.cc
2008-08-17 05:09:51 -04:00

334 lines
6.7 KiB
C++

/*
* Copyright (c) 2003-2008, John Wiegley. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met:
*
* - Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* - Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* - Neither the name of New Artisans LLC nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include "token.h"
#include "parser.h"
namespace ledger {
void expr_t::token_t::parse_ident(std::istream& in)
{
if (in.eof()) {
kind = TOK_EOF;
return;
}
assert(in.good());
char c = peek_next_nonws(in);
if (in.eof()) {
kind = TOK_EOF;
return;
}
assert(in.good());
kind = IDENT;
length = 0;
char buf[256];
READ_INTO_(in, buf, 255, c, length,
std::isalnum(c) || c == '_' || c == '.' || c == '-');
switch (buf[0]) {
case 'f':
if (std::strcmp(buf, "false") == 0) {
kind = VALUE;
value = false;
}
break;
case 't':
if (std::strcmp(buf, "true") == 0) {
kind = VALUE;
value = true;
}
break;
}
if (kind == IDENT)
value.set_string(buf);
}
void expr_t::token_t::next(std::istream& in, const uint_least8_t pflags)
{
if (in.eof()) {
kind = TOK_EOF;
return;
}
assert(in.good());
char c = peek_next_nonws(in);
if (in.eof()) {
kind = TOK_EOF;
return;
}
assert(in.good());
symbol[0] = c;
symbol[1] = '\0';
length = 1;
switch (c) {
case '&':
in.get(c);
kind = KW_AND;
break;
case '|':
in.get(c);
kind = KW_OR;
break;
case '(':
in.get(c);
kind = LPAREN;
break;
case ')':
in.get(c);
kind = RPAREN;
break;
case '[': {
in.get(c);
char buf[256];
READ_INTO_(in, buf, 255, c, length, c != ']');
if (c != ']')
expected(']', c);
in.get(c);
length++;
interval_t timespan(buf);
kind = VALUE;
value = timespan.first();
break;
}
case '\'':
case '"': {
char delim;
in.get(delim);
char buf[4096];
READ_INTO_(in, buf, 4095, c, length, c != delim);
if (c != delim)
expected(delim, c);
in.get(c);
length++;
kind = VALUE;
value.set_string(buf);
break;
}
case '{': {
in.get(c);
amount_t temp;
temp.parse(in, AMOUNT_PARSE_NO_MIGRATE);
in.get(c);
if (c != '}')
expected('}', c);
length++;
kind = VALUE;
value = temp;
break;
}
case '!':
in.get(c);
c = in.peek();
if (c == '=') {
in.get(c);
symbol[1] = c;
symbol[2] = '\0';
kind = NEQUAL;
length = 2;
break;
}
kind = EXCLAM;
break;
case '-':
in.get(c);
kind = MINUS;
break;
case '+':
in.get(c);
kind = PLUS;
break;
case '*':
in.get(c);
kind = STAR;
break;
case '?':
in.get(c);
kind = QUERY;
break;
case ':':
in.get(c);
kind = COLON;
break;
case '/': {
in.get(c);
// Read in the regexp
char buf[256];
READ_INTO_(in, buf, 255, c, length, c != '/');
if (c != '/')
expected('/', c);
in.get(c);
length++;
kind = MASK;
value.set_string(buf);
break;
}
case '=':
in.get(c);
c = in.peek();
if (c == '~') {
in.get(c);
symbol[1] = c;
symbol[2] = '\0';
kind = MATCH;
length = 2;
break;
}
kind = EQUAL;
break;
case '<':
in.get(c);
if (in.peek() == '=') {
in.get(c);
symbol[1] = c;
symbol[2] = '\0';
kind = LESSEQ;
length = 2;
break;
}
kind = LESS;
break;
case '>':
in.get(c);
if (in.peek() == '=') {
in.get(c);
symbol[1] = c;
symbol[2] = '\0';
kind = GREATEREQ;
length = 2;
break;
}
kind = GREATER;
break;
case ',':
in.get(c);
kind = COMMA;
break;
default: {
amount_t temp;
istream_pos_type pos = 0;
// When in relaxed parsing mode, we want to migrate commodity
// flags so that any precision specified by the user updates the
// current maximum displayed precision.
pos = in.tellg();
amount_t::flags_t parse_flags = 0;
if (pflags & EXPR_PARSE_NO_MIGRATE)
parse_flags |= AMOUNT_PARSE_NO_MIGRATE;
if (pflags & EXPR_PARSE_NO_REDUCE)
parse_flags |= AMOUNT_PARSE_NO_REDUCE;
if (! temp.parse(in, parse_flags | AMOUNT_PARSE_SOFT_FAIL)) {
// If the amount had no commodity, it must be an unambiguous
// variable reference
in.clear();
in.seekg(pos, std::ios::beg);
c = in.peek();
assert(! (std::isdigit(c) || c == '.'));
parse_ident(in);
} else {
kind = VALUE;
value = temp;
}
break;
}
}
}
void expr_t::token_t::rewind(std::istream& in)
{
for (unsigned int i = 0; i < length; i++)
in.unget();
}
void expr_t::token_t::unexpected()
{
switch (kind) {
case TOK_EOF:
throw_(parse_error, "Unexpected end of expression");
case IDENT:
throw_(parse_error, "Unexpected symbol '" << value << "'");
case VALUE:
throw_(parse_error, "Unexpected value '" << value << "'");
default:
throw_(parse_error, "Unexpected operator '" << symbol << "'");
}
}
void expr_t::token_t::expected(char wanted, char c)
{
if (c == '\0') {
if (wanted)
throw_(parse_error, "Missing '" << wanted << "'");
else
throw_(parse_error, "Unexpected end");
} else {
if (wanted)
throw_(parse_error, "Invalid char '" << c
<< "' (wanted '" << wanted << "')");
else
throw_(parse_error, "Invalid char '" << c << "'");
}
}
} // namespace ledger