string.c: Add missing documentation.

diff --git a/string.c b/string.c
index 77f2f2a17d27002b0fcf608a4b615f6beaa83b01..b3c28dab69512f44240d2c242130151515b47981 100644 (file)
--- a/string.c
+++ b/string.c
@@ -135,6 +135,13 @@ __must_check __printf_1_2 __malloc char *make_message(const char *fmt, ...)
        return msg;
 }
 
+/**
+ * Free the content of a pointer and set it to \p NULL.
+ *
+ * This is equivalent to "free(*arg); *arg = NULL;".
+ *
+ * \param arg The pointer whose content should be freed.
+ */
 void freep(void *arg)
 {
        void **ptr = (void **)arg;
@@ -393,7 +400,9 @@ int for_each_line_ro(char *buf, size_t size, line_handler_t *line_handler,
                private_data);
 }
 
+/** Return the hex characters of the lower 4 bits. */
 #define hex(a) (hexchar[(a) & 15])
+
 static void write_size_header(char *buf, int n)
 {
        static char hexchar[] = "0123456789abcdef";
@@ -405,6 +414,17 @@ static void write_size_header(char *buf, int n)
        buf[4] = ' ';
 }
 
+/**
+ * Read a four-byte hex-number and return its value.
+ *
+ * Each status item sent by para_server is prefixed with such a hex number in
+ * ASCII which describes the size of the status item.
+ *
+ * \param buf The buffer which must be at least four bytes long.
+ *
+ * \return The value of the hex number on success, \p -E_SIZE_PREFIX if the
+ * buffer did not contain only hex digits.
+ */
 int read_size_header(const char *buf)
 {
        int i, len = 0;
@@ -743,6 +763,17 @@ err:
        return ret;
 }
 
+/**
+ * Compile a regular expression.
+ *
+ * This simple wrapper calls regcomp() and logs a message on errors.
+ *
+ * \param preg See regcomp(3).
+ * \param regex See regcomp(3).
+ * \param cflags See regcomp(3).
+ *
+ * \return Standard.
+ */
 int para_regcomp(regex_t *preg, const char *regex, int cflags)
 {
        char *buf;