util: add strcmp_null, a strcmp that handles NULL parameters

[notmuch] / util / string-util.c

diff --git a/util/string-util.c b/util/string-util.c
index 9e2f728fc6750c586f3effed3ecac5673ea980e0..92af937f45ec15eab8ae00d27b287bf6a265134a 100644 (file)
--- a/util/string-util.c
+++ b/util/string-util.c
@@ -37,6 +37,14 @@ strtok_len (char *s, const char *delim, size_t *len)
     return *len ? s : NULL;
 }
 
+const char *
+strtok_len_c (const char *s, const char *delim, size_t *len)
+{
+    /* strtok_len is already const-safe, but we can't express both
+     * versions in the C type system. */
+    return strtok_len ((char*)s, delim, len);
+}
+
 char *
 sanitize_string (const void *ctx, const char *str)
 {
@@ -75,10 +83,12 @@ make_boolean_term (void *ctx, const char *prefix, const char *term,
     int need_quoting = 0;
 
     /* Do we need quoting?  To be paranoid, we quote anything
-     * containing a quote, even though it only matters at the
+     * containing a quote or '(', even though these only matter at the
      * beginning, and anything containing non-ASCII text. */
+    if (! term[0])
+       need_quoting = 1;
     for (in = term; *in && !need_quoting; in++)
-       if (is_unquoted_terminator (*in) || *in == '"'
+       if (is_unquoted_terminator (*in) || *in == '"' || *in == '('
            || (unsigned char)*in > 127)
            need_quoting = 1;
 
@@ -211,3 +221,37 @@ parse_boolean_term (void *ctx, const char *str,
     errno = err;
     return -1;
 }
+
+int
+strcmp_null (const char *s1, const char *s2)
+{
+    if (s1 && s2)
+       return strcmp (s1, s2);
+    else if (! s1 && ! s2)
+       return 0;
+    else if (s1)
+       return 1;       /* s1 (non-NULL) is greater than s2 (NULL) */
+    else
+       return -1;      /* s1 (NULL) is less than s2 (non-NULL) */
+}
+
+int
+strcase_equal (const void *a, const void *b)
+{
+    return strcasecmp (a, b) == 0;
+}
+
+unsigned int
+strcase_hash (const void *ptr)
+{
+    const char *s = ptr;
+
+    /* This is the djb2 hash. */
+    unsigned int hash = 5381;
+    while (s && *s) {
+       hash = ((hash << 5) + hash) + tolower (*s);
+       s++;
+    }
+
+    return hash;
+}