add serialize_to_text() function

For gdb static tracepoints.

diff --git a/libust/serialize.c b/libust/serialize.c
index beaf6390b544a4dd96f0b4c30afdb0692283435f..b1859ed9a8095f63bda857a72dd14ac1d492a52c 100644 (file)
--- a/libust/serialize.c
+++ b/libust/serialize.c
@@ -31,6 +31,7 @@
 //ust// #include <linux/ltt-tracer.h>
 #include <string.h>
 #include <stdint.h>
+#include <stdio.h>
 
 #include <ust/kernelcompat.h>
 #define _LGPL_SOURCE
@@ -500,6 +501,92 @@ copydone:
        return buf_offset;
 }
 
+static notrace void skip_space(const char **ps)
+{
+       while(**ps == ' ')
+               (*ps)++;
+}
+
+static notrace void copy_token(char **out, const char **in)
+{
+       while(**in != ' ' && **in != '\0') {
+               **out = **in;
+               (*out)++;
+               (*in)++;
+       }
+}
+
+/* serialize_to_text
+ *
+ * Given a format string and a va_list of arguments, convert them to a
+ * human-readable string.
+ *
+ * @outbuf: the buffer to output the string to
+ * @bufsize: the max size that can be used in outbuf
+ * @fmt: the marker format string
+ * @ap: a va_list that contains the arguments corresponding to fmt
+ *
+ * Return value: the number of chars that have been put in outbuf, excluding
+ * the final \0, or, if the buffer was too small, the number of chars that
+ * would have been written in outbuf if it had been large enough.
+ *
+ * outbuf may be NULL. The return value may then be used be allocate an
+ * appropriate outbuf.
+ *
+ */
+
+notrace
+int serialize_to_text(char *outbuf, int bufsize, const char *fmt, va_list ap)
+{
+       int fmt_len = strlen(fmt);
+       char *new_fmt = alloca(fmt_len + 1);
+       const char *orig_fmt_p = fmt;
+       char *new_fmt_p = new_fmt;
+       char false_buf;
+       int result;
+       enum { none, cfmt, tracefmt, argname } prev_token = none;
+
+       while(*orig_fmt_p != '\0') {
+               if(*orig_fmt_p == '%') {
+                       prev_token = cfmt;
+                       copy_token(&new_fmt_p, &orig_fmt_p);
+               }
+               else if(*orig_fmt_p == '#') {
+                       prev_token = tracefmt;
+                       do {
+                               orig_fmt_p++;
+                       } while(*orig_fmt_p != ' ' && *orig_fmt_p != '\0');
+               }
+               else if(*orig_fmt_p == ' ') {
+                       if(prev_token == argname) {
+                               *new_fmt_p = '=';
+                               new_fmt_p++;
+                       }
+                       else if(prev_token == cfmt) {
+                               *new_fmt_p = ' ';
+                               new_fmt_p++;
+                       }
+
+                       skip_space(&orig_fmt_p);
+               }
+               else {
+                       prev_token = argname;
+                       copy_token(&new_fmt_p, &orig_fmt_p);
+               }
+       }
+
+       *new_fmt_p = '\0';
+
+       if(outbuf == NULL) {
+               /* use this false_buffer for compatibility with pre-C99 */
+               outbuf = &false_buf;
+               bufsize = 1;
+       }
+       result = vsnprintf(outbuf, bufsize, new_fmt, ap);
+
+       return result;
+}
+
 notrace size_t ltt_serialize_data(struct rchan_buf *buf, size_t buf_offset,
                        struct ltt_serialize_closure *closure,
                        void *serialize_private, int *largest_align,