This parses the subset of Xapian's boolean term quoting rules that are
used by make_boolean_term. This is provided as a generic string
utility, but will be used shortly in notmuch restore to parse and
optimize for ID queries.
---
util/string-util.c | 67 ++++++++++++++++++++++++++++++++++++++++++++++++++++
util/string-util.h | 15 ++++++++++++
2 files changed, 82 insertions(+)
diff --git a/util/string-util.c b/util/string-util.c
index e4bea21..52c7781 100644
--- a/util/string-util.c
+++ b/util/string-util.c
@@ -22,6 +22,8 @@
#include "string-util.h"
#include "talloc.h"
+#include <ctype.h>
+
char *
strtok_len (char *s, const char *delim, size_t *len)
{
@@ -96,3 +98,68 @@ make_boolean_term (void *ctx, const char *prefix, const char
*term,
return 0;
}
+
+static const char*
+skip_space (const char *str)
+{
+ while (*str && isspace (*str))
+ ++str;
+ return str;
+}
+
+int
+parse_boolean_term (void *ctx, const char *str,
+ char **prefix_out, char **term_out)
+{
+ *prefix_out = *term_out = NULL;
+
+ /* Parse prefix */
+ str = skip_space (str);
+ const char *pos = strchr (str, ':');
+ if (! pos)
+ goto FAIL;
+ *prefix_out = talloc_strndup (ctx, str, pos - str);
+ ++pos;
+
+ /* Implement de-quoting compatible with make_boolean_term. */
+ if (*pos == '"') {
+ char *out = talloc_array (ctx, char, strlen (pos));
+ int closed = 0;
+ *term_out = out;
+ /* Skip the opening quote, find the closing quote, and
+ * un-double doubled internal quotes. */
+ for (++pos; *pos; ) {
+ if (*pos == '"') {
+ ++pos;
+ if (*pos != '"') {
+ /* Found the closing quote. */
+ closed = 1;
+ pos = skip_space (pos);
+ break;
+ }
+ }
+ *out++ = *pos++;
+ }
+ /* Did the term terminate without a closing quote or is there
+ * trailing text after the closing quote? */
+ if (!closed || *pos)
+ goto FAIL;
+ *out = '\0';
+ } else {
+ const char *start = pos;
+ /* Check for text after the boolean term. */
+ while (*pos > ' ' && *pos != ')')
+ ++pos;
+ if (*skip_space (pos))
+ goto FAIL;
+ /* No trailing text; dup the string so the caller can free
+ * it. */
+ *term_out = talloc_strndup (ctx, start, pos - start);
+ }
+ return 0;
+
+ FAIL:
+ talloc_free (*prefix_out);
+ talloc_free (*term_out);
+ return 1;
+}
diff --git a/util/string-util.h b/util/string-util.h
index b8844a3..8b9fe50 100644
--- a/util/string-util.h
+++ b/util/string-util.h
@@ -33,4 +33,19 @@ char *strtok_len (char *s, const char *delim, size_t *len);
int make_boolean_term (void *talloc_ctx, const char *prefix, const char *term,
char **buf, size_t *len);
+/* Parse a boolean term query consisting of a prefix, a colon, and a
+ * term that may be quoted as described for make_boolean_term. If the
+ * term is not quoted, then it ends at the first whitespace or close
+ * parenthesis. str may containing leading or trailing whitespace,
+ * but anything else is considered a parse error. This is compatible
+ * with anything produced by make_boolean_term, and supports a subset
+ * of the quoting styles supported by Xapian (and hence notmuch).
+ * *prefix_out and *term_out will be talloc'd with context ctx.
+ *
+ * Return: 0 on success, non-zero on parse error.
+ */
+int
+parse_boolean_term (void *ctx, const char *str,
+ char **prefix_out, char **term_out);
+
#endif
--
1.7.10.4
