/*
* malloc routines with failure handling.
*
* Usage:
*
* extern xmalloc_handler_t memory_error;
* extern const char *string;
* char *buffer;
* va_list args;
*
* xmalloc_error_handler = memory_error;
* buffer = xmalloc(1024);
* xrealloc(buffer, 2048);
* free(buffer);
* buffer = xcalloc(1024);
* free(buffer);
* buffer = xstrdup(string);
* free(buffer);
* buffer = xstrndup(string, 25);
* free(buffer);
* xasprintf(&buffer, "%s", "some string");
* free(buffer);
* xvasprintf(&buffer, "%s", args);
*
* xmalloc, xcalloc, xrealloc, and xstrdup behave exactly like their C library
* counterparts without the leading x except that they will never return NULL.
* Instead, on error, they call xmalloc_error_handler, passing it the name of
* the function whose memory allocation failed, the amount of the allocation,
* and the file and line number where the allocation function was invoked
* (from __FILE__ and __LINE__). This function may do whatever it wishes,
* such as some action to free up memory or a call to sleep to hope that
* system resources return. If the handler returns, the interrupted memory
* allocation function will try its allocation again (calling the handler
* again if it still fails).
*
* xstrndup behaves like xstrdup but only copies the given number of
* characters. It allocates an additional byte over its second argument and
* always nul-terminates the string.
*
* xasprintf and xvasprintf behave just like their GNU glibc library
* implementations except that they do the same checking as described above.
* xasprintf will only be able to provide accurate file and line information
* on systems that support variadic macros.
*
* The default error handler, if none is set by the caller, prints an error
* message to stderr and exits with exit status 1. An error handler must take
* a const char * (function name), size_t (bytes allocated), const char *
* (file), and int (line).
*
* xmalloc will return a pointer to a valid memory region on an xmalloc of 0
* bytes, ensuring this by allocating space for one character instead of 0
* bytes.
*
* The functions defined here are actually x_malloc, x_realloc, etc. The
* header file defines macros named xmalloc, etc. that pass the file name and
* line number to these functions.
*
* Copyright (c) 2004, 2005, 2006
* by Internet Systems Consortium, Inc. ("ISC")
* Copyright (c) 1991, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001,
* 2002, 2003 by The Internet Software Consortium and Rich Salz
*
* See LICENSE for licensing terms.
*/
#include <config.h>
#include <portable/system.h>
#include <errno.h>
#include <util/messages.h>
#include <util/xmalloc.h>
/*
* The default error handler.
*/
void
xmalloc_fail(const char *function, size_t size, const char *file, int line)
{
sysdie("failed to %s %lu bytes at %s line %d", function,
(unsigned long) size, file, line);
}
/* Assign to this variable to choose a handler other than the default. */
xmalloc_handler_type xmalloc_error_handler = xmalloc_fail;
void *
x_malloc(size_t size, const char *file, int line)
{
void *p;
size_t real_size;
real_size = (size > 0) ? size : 1;
p = malloc(real_size);
while (p == NULL) {
(*xmalloc_error_handler)("malloc", size, file, line);
p = malloc(real_size);
}
return p;
}
void *
x_calloc(size_t n, size_t size, const char *file, int line)
{
void *p;
n = (n > 0) ? n : 1;
size = (size > 0) ? size : 1;
p = calloc(n, size);
while (p == NULL) {
(*xmalloc_error_handler)("calloc", n * size, file, line);
p = calloc(n, size);
}
return p;
}
void *
x_realloc(void *p, size_t size, const char *file, int line)
{
void *newp;
newp = realloc(p, size);
while (newp == NULL && size > 0) {
(*xmalloc_error_handler)("realloc", size, file, line);
newp = realloc(p, size);
}
return newp;
}
char *
x_strdup(const char *s, const char *file, int line)
{
char *p;
size_t len;
len = strlen(s) + 1;
p = malloc(len);
while (p == NULL) {
(*xmalloc_error_handler)("strdup", len, file, line);
p = malloc(len);
}
memcpy(p, s, len);
return p;
}
char *
x_strndup(const char *s, size_t size, const char *file, int line)
{
char *p;
p = malloc(size + 1);
while (p == NULL) {
(*xmalloc_error_handler)("strndup", size + 1, file, line);
p = malloc(size + 1);
}
memcpy(p, s, size);
p[size] = '\0';
return p;
}
int
x_vasprintf(char **strp, const char *fmt, va_list args, const char *file,
int line)
{
va_list args_copy;
int status;
va_copy(args_copy, args);
status = vasprintf(strp, fmt, args_copy);
va_end(args_copy);
while (status < 0 && errno == ENOMEM) {
va_copy(args_copy, args);
status = vsnprintf(NULL, 0, fmt, args_copy);
va_end(args_copy);
(*xmalloc_error_handler)("vasprintf", status + 1, file, line);
va_copy(args_copy, args);
status = vasprintf(strp, fmt, args_copy);
va_end(args_copy);
}
return status;
}
#if HAVE_C99_VAMACROS || HAVE_GNU_VAMACROS
int
x_asprintf(char **strp, const char *file, int line, const char *fmt, ...)
{
va_list args, args_copy;
int status;
va_start(args, fmt);
va_copy(args_copy, args);
status = vasprintf(strp, fmt, args_copy);
va_end(args_copy);
while (status < 0 && errno == ENOMEM) {
va_copy(args_copy, args);
status = vsnprintf(NULL, 0, fmt, args_copy);
va_end(args_copy);
(*xmalloc_error_handler)("asprintf", status + 1, file, line);
va_copy(args_copy, args);
status = vasprintf(strp, fmt, args_copy);
va_end(args_copy);
}
return status;
}
#else /* !(HAVE_C99_VAMACROS || HAVE_GNU_VAMACROS) */
int
x_asprintf(char **strp, const char *fmt, ...)
{
va_list args, args_copy;
int status;
va_start(args, fmt);
va_copy(args_copy, args);
status = vasprintf(strp, fmt, args_copy);
va_end(args_copy);
while (status < 0 && errno == ENOMEM) {
va_copy(args_copy, args);
status = vsnprintf(NULL, 0, fmt, args_copy);
va_end(args_copy);
(*xmalloc_error_handler)("asprintf", status + 1, __FILE__, __LINE__);
va_copy(args_copy, args);
status = vasprintf(strp, fmt, args_copy);
va_end(args_copy);
}
return status;
}
#endif /* !(HAVE_C99_VAMACROS || HAVE_GNU_VAMACROS) */