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/*
*
* Copyright 2015-2016, Google Inc.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following disclaimer
* in the documentation and/or other materials provided with the
* distribution.
* * Neither the name of Google Inc. nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
*/
#include <grpc/support/port_platform.h>
#ifdef GPR_POSIX_STRING
#include <stdarg.h>
#include <stdio.h>
#include <string.h>
#include <grpc/support/alloc.h>
int gpr_asprintf(char **strp, const char *format, ...) {
va_list args;
int ret;
char buf[64];
size_t strp_buflen;
/* Use a constant-sized buffer to determine the length. */
va_start(args, format);
ret = vsnprintf(buf, sizeof(buf), format, args);
va_end(args);
if (ret < 0) {
*strp = NULL;
return -1;
}
/* Allocate a new buffer, with space for the NUL terminator. */
strp_buflen = (size_t)ret + 1;
if ((*strp = gpr_malloc(strp_buflen)) == NULL) {
/* This shouldn't happen, because gpr_malloc() calls abort(). */
return -1;
}
/* Return early if we have all the bytes. */
if (strp_buflen <= sizeof(buf)) {
memcpy(*strp, buf, strp_buflen);
return ret;
}
/* Try again using the larger buffer. */
va_start(args, format);
ret = vsnprintf(*strp, strp_buflen, format, args);
va_end(args);
if ((size_t)ret == strp_buflen - 1) {
return ret;
}
/* This should never happen. */
gpr_free(*strp);
*strp = NULL;
return -1;
}
#endif /* GPR_POSIX_STRING */
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