blob: e7bed1ed9d3d215ac22522a1dd8c52c363fe331a [file] [log] [blame]
/*
* Functions used to parse typed argument lists
*
* Copyright 2012 Willy Tarreau <w@1wt.eu>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*
*/
#include <sys/types.h>
#include <sys/socket.h>
#include <arpa/inet.h>
#include <common/standard.h>
#include <proto/arg.h>
static const char *arg_type_names[ARGT_NBTYPES] = {
[ARGT_STOP] = "end of arguments",
[ARGT_UINT] = "unsigned integer",
[ARGT_SINT] = "signed integer",
[ARGT_STR] = "string",
[ARGT_IPV4] = "IPv4 address",
[ARGT_MSK4] = "IPv4 mask",
[ARGT_IPV6] = "IPv6 address",
[ARGT_MSK6] = "IPv6 mask",
[ARGT_TIME] = "delay",
[ARGT_SIZE] = "size",
[ARGT_FE] = "frontend",
[ARGT_BE] = "backend",
[ARGT_TAB] = "table",
[ARGT_SRV] = "server",
[ARGT_USR] = "user list",
/* Unassigned types must never happen. Better crash during parsing if they do. */
};
/* This dummy arg list may be used by default when no arg is found, it helps
* parsers by removing pointer checks.
*/
struct arg empty_arg_list[8] = { };
/* This function clones a struct arg_list template into a new one which is
* returned.
*/
struct arg_list *arg_list_clone(const struct arg_list *orig)
{
struct arg_list *new;
if ((new = calloc(1, sizeof(*new))) != NULL) {
/* ->list will be set by the caller when inserting the element.
* ->arg and ->arg_pos will be set by the caller.
*/
new->ctx = orig->ctx;
new->kw = orig->kw;
new->conv = orig->conv;
new->file = orig->file;
new->line = orig->line;
}
return new;
}
/* This function clones a struct <arg_list> template into a new one which is
* set to point to arg <arg> at pos <pos>, and which is returned if the caller
* wants to apply further changes.
*/
struct arg_list *arg_list_add(struct arg_list *orig, struct arg *arg, int pos)
{
struct arg_list *new;
new = arg_list_clone(orig);
new->arg = arg;
new->arg_pos = pos;
LIST_ADDQ(&orig->list, &new->list);
return new;
}
/* This function builds an argument list from a config line. It returns the
* number of arguments found, or <0 in case of any error. Everything needed
* it automatically allocated. A pointer to an error message might be returned
* in err_msg if not NULL, in which case it would be allocated and the caller
* will have to check it and free it. The output arg list is returned in argp
* which must be valid. The returned array is always terminated by an arg of
* type ARGT_STOP (0), unless the mask indicates that no argument is supported.
* Unresolved arguments are appended to arg list <al>, which also serves as a
* template to create new entries. The mask is composed of a number of
* mandatory arguments in its lower 4 bits, and a concatenation of each
* argument type in each subsequent 4-bit block. If <err_msg> is not NULL, it
* must point to a freeable or NULL pointer.
*/
int make_arg_list(const char *in, int len, unsigned int mask, struct arg **argp,
char **err_msg, const char **err_ptr, int *err_arg,
struct arg_list *al)
{
int nbarg;
int pos;
struct arg *arg;
const char *beg;
char *word = NULL;
const char *ptr_err = NULL;
int min_arg;
*argp = NULL;
min_arg = mask & 15;
mask >>= 4;
pos = 0;
/* find between 0 and 8 the max number of args supported by the mask */
for (nbarg = 0; nbarg < 8 && ((mask >> (nbarg * 4)) & 0xF); nbarg++);
if (!nbarg)
goto end_parse;
/* Note: an empty input string contains an empty argument if this argument
* is marked mandatory. Otherwise we can ignore it.
*/
if (!len && !min_arg)
goto end_parse;
arg = *argp = calloc(nbarg + 1, sizeof(*arg));
/* Note: empty arguments after a comma always exist. */
while (pos < nbarg) {
beg = in;
while (len && *in != ',') {
in++;
len--;
}
/* we have a new argument between <beg> and <in> (not included).
* For ease of handling, we copy it into a zero-terminated word.
* By default, the output argument will be the same type of the
* expected one.
*/
free(word);
word = my_strndup(beg, in - beg);
arg->type = (mask >> (pos * 4)) & 15;
switch (arg->type) {
case ARGT_SINT:
if (in == beg) // empty number
goto empty_err;
else if (*beg < '0' || *beg > '9') {
beg++;
arg->data.sint = read_uint(&beg, in);
if (beg < in)
goto parse_err;
if (*word == '-')
arg->data.sint = -arg->data.sint;
else if (*word != '+') // invalid first character
goto parse_err;
break;
}
arg->type = ARGT_UINT;
/* fall through ARGT_UINT if no sign is present */
case ARGT_UINT:
if (in == beg) // empty number
goto empty_err;
arg->data.uint = read_uint(&beg, in);
if (beg < in)
goto parse_err;
break;
case ARGT_FE:
case ARGT_BE:
case ARGT_TAB:
case ARGT_SRV:
case ARGT_USR:
/* These argument types need to be stored as strings during
* parsing then resolved later.
*/
arg->unresolved = 1;
arg_list_add(al, arg, pos);
/* fall through */
case ARGT_STR:
/* all types that must be resolved are stored as strings
* during the parsing. The caller must at one point resolve
* them and free the string.
*/
arg->data.str.str = word;
arg->data.str.len = in - beg;
arg->data.str.size = arg->data.str.len + 1;
word = NULL;
break;
case ARGT_IPV4:
if (in == beg) // empty address
goto empty_err;
if (inet_pton(AF_INET, word, &arg->data.ipv4) <= 0)
goto parse_err;
break;
case ARGT_MSK4:
if (in == beg) // empty mask
goto empty_err;
if (!str2mask(word, &arg->data.ipv4))
goto parse_err;
arg->type = ARGT_IPV4;
break;
case ARGT_IPV6:
if (in == beg) // empty address
goto empty_err;
if (inet_pton(AF_INET6, word, &arg->data.ipv6) <= 0)
goto parse_err;
break;
case ARGT_MSK6: /* not yet implemented */
goto not_impl;
case ARGT_TIME:
if (in == beg) // empty time
goto empty_err;
ptr_err = parse_time_err(word, &arg->data.uint, TIME_UNIT_MS);
if (ptr_err)
goto parse_err;
arg->type = ARGT_UINT;
break;
case ARGT_SIZE:
if (in == beg) // empty size
goto empty_err;
ptr_err = parse_size_err(word, &arg->data.uint);
if (ptr_err)
goto parse_err;
arg->type = ARGT_UINT;
break;
/* FIXME: other types need to be implemented here */
default:
goto not_impl;
}
pos++;
arg++;
/* don't go back to parsing if we reached end */
if (!len || pos >= nbarg)
break;
/* skip comma */
in++; len--;
}
end_parse:
free(word); word = NULL;
if (pos < min_arg) {
/* not enough arguments */
memprintf(err_msg,
"Missing arguments (got %d/%d), type '%s' expected",
pos, min_arg, arg_type_names[(mask >> (pos * 4)) & 15]);
goto err;
}
if (len) {
/* too many arguments, starting at <in> */
/* the caller is responsible for freeing this message */
word = my_strndup(in, len);
memprintf(err_msg, "end of arguments expected at position %d, but got '%s'",
pos + 1, word);
free(word); word = NULL;
goto err;
}
/* note that pos might be < nbarg and this is not an error, it's up to the
* caller to decide what to do with optional args.
*/
if (err_arg)
*err_arg = pos;
if (err_ptr)
*err_ptr = in;
return pos;
err:
free(word);
free(*argp);
*argp = NULL;
if (err_arg)
*err_arg = pos;
if (err_ptr)
*err_ptr = in;
return -1;
empty_err:
memprintf(err_msg, "expected type '%s' at position %d, but got nothing",
arg_type_names[(mask >> (pos * 4)) & 15], pos + 1);
goto err;
parse_err:
memprintf(err_msg, "failed to parse '%s' as type '%s' at position %d",
word, arg_type_names[(mask >> (pos * 4)) & 15], pos + 1);
goto err;
not_impl:
memprintf(err_msg, "parsing for type '%s' was not implemented, please report this bug",
arg_type_names[(mask >> (pos * 4)) & 15]);
goto err;
}