util: add strcmp_null, a strcmp that handles NULL parameters

[notmuch] / util / string-util.h

diff --git a/util/string-util.h b/util/string-util.h
index ac7676c883d742febbbcc3614f2f6a35a57eefe1..87917b8fd279de6e07f2fb919429fb50512a85b4 100644 (file)
--- a/util/string-util.h
+++ b/util/string-util.h
@@ -3,6 +3,10 @@
 
 #include <string.h>
 
+#ifdef __cplusplus
+extern "C" {
+#endif
+
 /* like strtok(3), but without state, and doesn't modify s.  Return
  * value is indicated by pointer and length, not null terminator.
  *
@@ -19,4 +23,60 @@
 
 char *strtok_len (char *s, const char *delim, size_t *len);
 
+/* Const version of strtok_len. */
+const char *strtok_len_c (const char *s, const char *delim, size_t *len);
+
+/* Return a talloced string with str sanitized.
+ *
+ * Whitespace characters (tabs and newlines) are replaced with spaces,
+ * non-printable characters with question marks.
+ */
+char *sanitize_string (const void *ctx, const char *str);
+
+/* Construct a boolean term query with the specified prefix (e.g.,
+ * "id") and search term, quoting term as necessary.  Specifically, if
+ * term contains any non-printable ASCII characters, non-ASCII
+ * characters, close parenthesis or double quotes, it will be enclosed
+ * in double quotes and any internal double quotes will be doubled
+ * (e.g. a"b -> "a""b").  The result will be a valid notmuch query and
+ * can be parsed by parse_boolean_term.
+ *
+ * Output is into buf; it may be talloc_realloced.
+ * Return: 0 on success, -1 on error.  errno will be set to ENOMEM if
+ * there is an allocation failure.
+ */
+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, -1 on error.  errno will be set to EINVAL if
+ * there is a parse error or ENOMEM if there is an allocation failure.
+ */
+int
+parse_boolean_term (void *ctx, const char *str,
+                   char **prefix_out, char **term_out);
+
+/* strcmp that handles NULL strings; in strcmp terms a NULL string is
+ * considered to be less than a non-NULL string.
+ */
+int strcmp_null (const char *s1, const char *s2);
+
+/* GLib GEqualFunc compatible strcasecmp wrapper */
+int strcase_equal (const void *a, const void *b);
+
+/* GLib GHashFunc compatible case insensitive hash function */
+unsigned int strcase_hash (const void *ptr);
+
+#ifdef __cplusplus
+}
+#endif
+
 #endif