On Mon, 31 Dec 2012, Austin Clements <amdragon at MIT.EDU> wrote: > 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))
Pedantic: isspace ((unsigned char) *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) if (! pos || pos == str) ? > + goto FAIL; Could just return 1 here. > + *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); Is it necessary to accept trailing space? > + 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 != ')') The condition could have *pos there too for clarity, though not strictly necessary. Would be neat to have a ctype style helper that could be shared between this and make_boolean_term. > + ++pos; > + if (*skip_space (pos)) Is it necessary to accept trailing space? > + 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