buf_util.c

// SPDX-License-Identifier: Apache-2.0

#include "config.h"

#include "buf_util.h"

#include <errno.h>
#include <string.h>

void BufWriterInit(struct BufWriter *w, char *buf, size_t size) {
  if (w == NULL) {
    return;
  }
  w->ptr = buf;
  w->remaining = size;
  if (buf != NULL && size > 0) {
    buf[0] = '\0';
  }
}

int BufWriteBytes(struct BufWriter *w, const void *src, size_t len) {
  if (w == NULL || src == NULL || w->ptr == NULL) {
    errno = EINVAL;
    return -1;
  }

  if (w->remaining == 0 || len > w->remaining - 1) {
    errno = ENOSPC;
    return -1;
  }

  if (len != 0) {
    memcpy(w->ptr, src, len);
  }
  w->ptr[len] = '\0';
  w->ptr += len;
  w->remaining -= len;
  return 0;
}

int BufWriteCString(struct BufWriter *w, const char *src) {
  if (src == NULL) {
    errno = EINVAL;
    return -1;
  }
  return BufWriteBytes(w, src, strlen(src));
}

void BufWriteBytesTruncated(struct BufWriter *w, const void *src, size_t len) {
  if (w == NULL || src == NULL || w->ptr == NULL || w->remaining == 0) {
    return;
  }

  size_t write_len = len;
  if (write_len > w->remaining - 1) {
    write_len = w->remaining - 1;
  }
  if (write_len != 0) {
    memcpy(w->ptr, src, write_len);
  }
  w->ptr[write_len] = '\0';
  w->ptr += write_len;
  w->remaining -= write_len;
}

void BufWriteCStringTruncated(struct BufWriter *w, const char *src) {
  if (src == NULL) {
    return;
  }
  BufWriteBytesTruncated(w, src, strlen(src));
}