notmuch/lib/parse-sexp.cc
David Bremner f83cd2a05a lib/parse-sexp: support and, not, and or.
All operations and (Xapian) fields will eventually have an entry in
the prefixes table. The flags field is just a placeholder for now, but
will eventually distinguish between various kinds of prefixes.
2021-09-04 17:07:19 -07:00

125 lines
3.2 KiB
C++

#include "database-private.h"
#if HAVE_SFSEXP
#include "sexp.h"
/* _sexp is used for file scope symbols to avoid clashing with
* definitions from sexp.h */
typedef enum {
SEXP_FLAG_NONE = 0,
} _sexp_flag_t;
typedef struct {
const char *name;
Xapian::Query::op xapian_op;
Xapian::Query initial;
_sexp_flag_t flags;
} _sexp_prefix_t;
static _sexp_prefix_t prefixes[] =
{
{ "and", Xapian::Query::OP_AND, Xapian::Query::MatchAll,
SEXP_FLAG_NONE },
{ "not", Xapian::Query::OP_AND_NOT, Xapian::Query::MatchAll,
SEXP_FLAG_NONE },
{ "or", Xapian::Query::OP_OR, Xapian::Query::MatchNothing,
SEXP_FLAG_NONE },
{ }
};
static notmuch_status_t _sexp_to_xapian_query (notmuch_database_t *notmuch,
const _sexp_prefix_t *parent,
const sexp_t *sx,
Xapian::Query &output);
static notmuch_status_t
_sexp_combine_query (notmuch_database_t *notmuch,
const _sexp_prefix_t *parent,
Xapian::Query::op operation,
Xapian::Query left,
const sexp_t *sx,
Xapian::Query &output)
{
Xapian::Query subquery;
notmuch_status_t status;
/* if we run out elements, return accumulator */
if (! sx) {
output = left;
return NOTMUCH_STATUS_SUCCESS;
}
status = _sexp_to_xapian_query (notmuch, parent, sx, subquery);
if (status)
return status;
return _sexp_combine_query (notmuch,
parent,
operation,
Xapian::Query (operation, left, subquery),
sx->next, output);
}
/* Here we expect the s-expression to be a proper list, with first
* element defining and operation, or as a special case the empty
* list */
static notmuch_status_t
_sexp_to_xapian_query (notmuch_database_t *notmuch, const _sexp_prefix_t *parent, const sexp_t *sx,
Xapian::Query &output)
{
if (sx->ty == SEXP_VALUE) {
std::string term = Xapian::Unicode::tolower (sx->val);
Xapian::Stem stem = *(notmuch->stemmer);
if (sx->aty == SEXP_BASIC)
term = "Z" + stem (term);
output = Xapian::Query (term);
return NOTMUCH_STATUS_SUCCESS;
}
/* Empty list */
if (! sx->list) {
output = Xapian::Query::MatchAll;
return NOTMUCH_STATUS_SUCCESS;
}
if (sx->list->ty == SEXP_LIST) {
_notmuch_database_log (notmuch, "unexpected list in field/operation position\n",
sx->list->val);
return NOTMUCH_STATUS_BAD_QUERY_SYNTAX;
}
for (_sexp_prefix_t *prefix = prefixes; prefix && prefix->name; prefix++) {
if (strcmp (prefix->name, sx->list->val) == 0) {
return _sexp_combine_query (notmuch, parent, prefix->xapian_op, prefix->initial,
sx->list->next, output);
}
}
_notmuch_database_log (notmuch, "unknown prefix '%s'\n", sx->list->val);
return NOTMUCH_STATUS_BAD_QUERY_SYNTAX;
}
notmuch_status_t
_notmuch_sexp_string_to_xapian_query (notmuch_database_t *notmuch, const char *querystr,
Xapian::Query &output)
{
const sexp_t *sx = NULL;
char *buf = talloc_strdup (notmuch, querystr);
sx = parse_sexp (buf, strlen (querystr));
if (! sx) {
_notmuch_database_log (notmuch, "invalid s-expression: '%s'\n", querystr);
return NOTMUCH_STATUS_BAD_QUERY_SYNTAX;
}
return _sexp_to_xapian_query (notmuch, NULL, sx, output);
}
#endif