// SPDX-License-Identifier: GPL-2.0-or-later

/*

 * Simple string buffer

 *

 * Copyright (C) 2017 Christian Franke

 */

#include <zebra.h>

#include "printfrr.h"

#include "sbuf.h"

#include "memory.h"

void sbuf_init(struct sbuf *dest, char *buf, size_t size)

{

  dest->fixed = (size > 0);

  if (dest->fixed) {

    dest->buf = buf;

    dest->size = size;

  } else {

    dest->buf = XMALLOC(MTYPE_TMP, SBUF_DEFAULT_SIZE);

    dest->size = SBUF_DEFAULT_SIZE;

  }

  dest->pos = 0;

  dest->buf[0] = '\0';

}

void sbuf_reset(struct sbuf *dest)

{

  dest->pos = 0;

  dest->buf[0] = '\0';

}

const char *sbuf_buf(struct sbuf *buf)

{

  return buf->buf;

}

void sbuf_free(struct sbuf *buf)

{

  if (!buf->fixed)

    XFREE(MTYPE_TMP, buf->buf);

}

void sbuf_push(struct sbuf *buf, int indent, const char *format, ...)

{

  va_list args;

  int written;

  if (!buf->fixed) {

    int written1, written2;

    size_t new_size;

    written1 = indent;

    va_start(args, format);

    written2 = vsnprintfrr(NULL, 0, format, args);

    va_end(args);

    new_size = buf->size;

    if (written1 >= 0 && written2 >= 0) {

      while (buf->pos + written1 + written2 >= new_size)

        new_size *= 2;

      if (new_size > buf->size) {

        buf->buf =

          XREALLOC(MTYPE_TMP, buf->buf, new_size);

        buf->size = new_size;

      }

    }

  }

  written = snprintf(buf->buf + buf->pos, buf->size - buf->pos, "%*s",

         indent, "");

  if (written >= 0)

    buf->pos += written;

  if (buf->pos > buf->size)

    buf->pos = buf->size;

  va_start(args, format);

  written = vsnprintfrr(buf->buf + buf->pos, buf->size - buf->pos,

            format, args);

  va_end(args);

  if (written >= 0)

    buf->pos += written;

  if (buf->pos > buf->size)

    buf->pos = buf->size;

  if (buf->pos == buf->size)

    assert(!"Buffer filled up!");

}