xbuf_repl is not replacing all occurences

Question

As g-wan documented, xbuf_repl is replacing all occurrences. But my installed g-wan, running the following code, only replaced the first occurrence of the matched.

#include "gwan.h"

int main(int argc, char* argv[]){

    xbuf_t *reply = get_reply(argv);

    char str[ ] = "kjfdkkkkfldjfjfldkjdkkklfjworhg8kkkugpugulrghkkkr8g";
    xbuf_ncat(reply, str, sizeof(str)-1);
    xbuf_repl(reply, "kkk", "((()))");

    return 200;
}

output is : kjfd((()))kfldjfjfldkjdkkklfjworhg8kkkugpugulrghkkkr8g

What's wrong of my code? How to work around it?

Answer 1

According to the G-WAN API documentation . . .

// replace the first occurence of the 'old' string by the 'new' string in the buffer
char *xbuf_repl    (xbuf_t *ctx, char *old, char *new);

G-WAN also has this API, which (as I just learned from Gil's answer) also only replaces the first occurrence but within a range of the buffer rather than first occurrence from the beginning of the buffer . . . .

// same as above but using a range in the buffer
char *xbuf_replfrto(xbuf_t *ctx, char *beg, char *end, char *old, char *new);

Gil's answer shows how you can make use of this to replace ALL occurrences within the buffer.

Ken

Answer 2

In the entity.c G-WAN example, you can see:

  // escape '<' because it cuts the text
  while(xbuf_replfrto(reply, pos, reply->ptr + reply->len - 13, "<", "&lt;"));

This while() makes it obvious that one instance is replaced at a time, which is confirmed by the G-WAN documentation:

// replace the first occurence of the 'old' string by the 'new' string in the buffer
char *xbuf_repl    (xbuf_t *ctx, char *old, char *new);