talloc.c

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static void talloc_report_depth_FILE_helper(const void *ptr, int depth, int max_depth, int is_ref, void *_f)
{
	const char *name = talloc_get_name(ptr);
	FILE *f = (FILE *)_f;

	if (is_ref) {
		fprintf(f, "%*sreference to: %s\n", depth*4, "", name);
		return;
	}

	if (depth == 0) {
		fprintf(f,"%stalloc report on '%s' (total %6lu bytes in %3lu blocks)\n", 
			(max_depth < 0 ? "full " :""), name,
			(unsigned long)talloc_total_size(ptr),
			(unsigned long)talloc_total_blocks(ptr));
		return;
	}

	fprintf(f, "%*s%-30s contains %6lu bytes in %3lu blocks (ref %d) %p\n", 
		depth*4, "",
		name,
		(unsigned long)talloc_total_size(ptr),
		(unsigned long)talloc_total_blocks(ptr),
		(int)talloc_reference_count(ptr), ptr);

#if 0
	fprintf(f, "content: ");
	if (talloc_total_size(ptr)) {
		int tot = talloc_total_size(ptr);
		int i;

		for (i = 0; i < tot; i++) {
			if ((((char *)ptr)[i] > 31) && (((char *)ptr)[i] < 126)) {
				fprintf(f, "%c", ((char *)ptr)[i]);
			} else {
				fprintf(f, "~%02x", ((char *)ptr)[i]);
			}
		}
	}
	fprintf(f, "\n");
#endif
}

/*
  report on memory usage by all children of a pointer, giving a full tree view
*/
void talloc_report_depth_file(const void *ptr, int depth, int max_depth, FILE *f)
{
	talloc_report_depth_cb(ptr, depth, max_depth, talloc_report_depth_FILE_helper, f);
	fflush(f);
}

/*
  report on memory usage by all children of a pointer, giving a full tree view
*/
void talloc_report_full(const void *ptr, FILE *f)
{
	talloc_report_depth_file(ptr, 0, -1, f);
}

/*
  report on memory usage by all children of a pointer
*/
void talloc_report(const void *ptr, FILE *f)
{
	talloc_report_depth_file(ptr, 0, 1, f);
}

/*
  report on any memory hanging off the null context
*/
static void talloc_report_null(void)
{
	if (talloc_total_size(null_context) != 0) {
		talloc_report(null_context, stderr);
	}
}

/*
  report on any memory hanging off the null context
*/
static void talloc_report_null_full(void)
{
	if (talloc_total_size(null_context) != 0) {
		talloc_report_full(null_context, stderr);
	}
}

/*
  enable tracking of the NULL context
*/
void talloc_enable_null_tracking(void)
{
	if (null_context == NULL) {
		null_context = _talloc_named_const(NULL, 0, "null_context");
	}
}

/*
  disable tracking of the NULL context
*/
void talloc_disable_null_tracking(void)
{
	_talloc_free(null_context);
	null_context = NULL;
}

/*
  enable leak reporting on exit
*/
void talloc_enable_leak_report(void)
{
	talloc_enable_null_tracking();
	atexit(talloc_report_null);
}

/*
  enable full leak reporting on exit
*/
void talloc_enable_leak_report_full(void)
{
	talloc_enable_null_tracking();
	atexit(talloc_report_null_full);
}

/* 
   talloc and zero memory. 
*/
void *_talloc_zero(const void *ctx, size_t size, const char *name)
{
	void *p = _talloc_named_const(ctx, size, name);

	if (p) {
		memset(p, '\0', size);
	}

	return p;
}

/*
  memdup with a talloc. 
*/
void *_talloc_memdup(const void *t, const void *p, size_t size, const char *name)
{
	void *newp = _talloc_named_const(t, size, name);

	if (likely(newp)) {
		memcpy(newp, p, size);
	}

	return newp;
}

/*
  strdup with a talloc 
*/
char *talloc_strdup(const void *t, const char *p)
{
	char *ret;
	if (!p) {
		return NULL;
	}
	ret = (char *)talloc_memdup(t, p, strlen(p) + 1);
	if (likely(ret)) {
		_talloc_set_name_const(ret, ret);
	}
	return ret;
}

/*
 append to a talloced string 
*/
char *talloc_append_string(const void *t, char *orig, const char *append)
{
	char *ret;
	size_t olen = strlen(orig);
	size_t alenz;

	if (!append)
		return orig;

	alenz = strlen(append) + 1;

	ret = talloc_realloc(t, orig, char, olen + alenz);
	if (!ret)
		return NULL;

	/* append the string with the trailing \0 */
	memcpy(&ret[olen], append, alenz);

	return ret;
}

/*
  strndup with a talloc 
*/
char *talloc_strndup(const void *t, const char *p, size_t n)
{
	size_t len;
	char *ret;

	for (len=0; len<n && p[len]; len++) ;

	ret = (char *)__talloc(t, len + 1);
	if (!ret) { return NULL; }
	memcpy(ret, p, len);
	ret[len] = 0;
	_talloc_set_name_const(ret, ret);
	return ret;
}

#ifndef HAVE_VA_COPY
#ifdef HAVE___VA_COPY
#define va_copy(dest, src) __va_copy(dest, src)
#else
#define va_copy(dest, src) (dest) = (src)
#endif
#endif

char *talloc_vasprintf(const void *t, const char *fmt, va_list ap)
{	
	int len;
	char *ret;
	va_list ap2;
	char c;
	
	/* this call looks strange, but it makes it work on older solaris boxes */
	va_copy(ap2, ap);
	len = vsnprintf(&c, 1, fmt, ap2);
	va_end(ap2);
	if (len < 0) {
		return NULL;
	}

	ret = (char *)__talloc(t, len+1);
	if (ret) {
		va_copy(ap2, ap);
		vsnprintf(ret, len+1, fmt, ap2);
		va_end(ap2);
		_talloc_set_name_const(ret, ret);
	}

	return ret;
}


/*
  Perform string formatting, and return a pointer to newly allocated
  memory holding the result, inside a memory pool.
 */
char *talloc_asprintf(const void *t, const char *fmt, ...)
{
	va_list ap;
	char *ret;

	va_start(ap, fmt);
	ret = talloc_vasprintf(t, fmt, ap);
	va_end(ap);
	return ret;
}


/**
 * Realloc @p s to append the formatted result of @p fmt and @p ap,
 * and return @p s, which may have moved.  Good for gradually
 * accumulating output into a string buffer.
 **/
char *talloc_vasprintf_append(char *s, const char *fmt, va_list ap)
{	
	struct talloc_chunk *tc;
	int len, s_len;
	va_list ap2;
	char c;

	if (s == NULL) {
		return talloc_vasprintf(NULL, fmt, ap);
	}

	tc = talloc_chunk_from_ptr(s);

	s_len = tc->size - 1;

	va_copy(ap2, ap);
	len = vsnprintf(&c, 1, fmt, ap2);
	va_end(ap2);

	if (len <= 0) {
		/* Either the vsnprintf failed or the format resulted in
		 * no characters being formatted. In the former case, we
		 * ought to return NULL, in the latter we ought to return
		 * the original string. Most current callers of this 
		 * function expect it to never return NULL.
		 */
		return s;
	}

	s = talloc_realloc(NULL, s, char, s_len + len+1);
	if (!s) return NULL;

	va_copy(ap2, ap);
	vsnprintf(s+s_len, len+1, fmt, ap2);
	va_end(ap2);
	_talloc_set_name_const(s, s);

	return s;
}

/*
  Realloc @p s to append the formatted result of @p fmt and return @p
  s, which may have moved.  Good for gradually accumulating output
  into a string buffer.
 */
char *talloc_asprintf_append(char *s, const char *fmt, ...)
{
	va_list ap;

	va_start(ap, fmt);
	s = talloc_vasprintf_append(s, fmt, ap);
	va_end(ap);
	return s;
}

/*
  alloc an array, checking for integer overflow in the array size
*/
void *_talloc_array(const void *ctx, size_t el_size, unsigned count, const char *name)
{
	if (count >= MAX_TALLOC_SIZE/el_size) {
		return NULL;
	}
	return _talloc_named_const(ctx, el_size * count, name);
}

/*
  alloc an zero array, checking for integer overflow in the array size
*/
void *_talloc_zero_array(const void *ctx, size_t el_size, unsigned count, const char *name)
{
	if (count >= MAX_TALLOC_SIZE/el_size) {
		return NULL;
	}
	return _talloc_zero(ctx, el_size * count, name);
}

/*
  realloc an array, checking for integer overflow in the array size
*/
void *_talloc_realloc_array(const void *ctx, void *ptr, size_t el_size, unsigned count, const char *name)
{
	if (count >= MAX_TALLOC_SIZE/el_size) {
		return NULL;
	}
	return _talloc_realloc(ctx, ptr, el_size * count, name);
}

/*
  a function version of talloc_realloc(), so it can be passed as a function pointer
  to libraries that want a realloc function (a realloc function encapsulates
  all the basic capabilities of an allocation library, which is why this is useful)
*/
void *talloc_realloc_fn(const void *context, void *ptr, size_t size)
{
	return _talloc_realloc(context, ptr, size, NULL);
}


static int talloc_autofree_destructor(void *ptr)
{
	autofree_context = NULL;
	return 0;
}

static void talloc_autofree(void)
{
	_talloc_free(autofree_context);
}

/*
  return a context which will be auto-freed on exit
  this is useful for reducing the noise in leak reports
*/
void *talloc_autofree_context(void)
{
	if (autofree_context == NULL) {
		autofree_context = _talloc_named_const(NULL, 0, "autofree_context");
		talloc_set_destructor(autofree_context, talloc_autofree_destructor);
		atexit(talloc_autofree);
	}
	return autofree_context;
}

size_t talloc_get_size(const void *context)
{
	struct talloc_chunk *tc;

	if (context == NULL)
		return 0;

	tc = talloc_chunk_from_ptr(context);

	return tc->size;
}

/*
  find a parent of this context that has the given name, if any
*/
void *talloc_find_parent_byname(const void *context, const char *name)
{
	struct talloc_chunk *tc;

	if (context == NULL) {
		return NULL;
	}

	tc = talloc_chunk_from_ptr(context);
	while (tc) {
		if (tc->name && strcmp(tc->name, name) == 0) {
			return TC_PTR_FROM_CHUNK(tc);
		}
		while (tc && tc->prev) tc = tc->prev;
		if (tc) {
			tc = tc->parent;
		}
	}
	return NULL;
}

/*
  show the parentage of a context
*/
void talloc_show_parents(const void *context, FILE *file)
{
	struct talloc_chunk *tc;

	if (context == NULL) {
		fprintf(file, "talloc no parents for NULL\n");
		return;
	}

	tc = talloc_chunk_from_ptr(context);
	fprintf(file, "talloc parents of '%s'\n", talloc_get_name(context));
	while (tc) {
		fprintf(file, "\t'%s'\n", talloc_get_name(TC_PTR_FROM_CHUNK(tc)));
		while (tc && tc->prev) tc = tc->prev;
		if (tc) {
			tc = tc->parent;
		}
	}
	fflush(file);
}

/*
  return 1 if ptr is a parent of context
*/
int talloc_is_parent(const void *context, const void *ptr)
{
	struct talloc_chunk *tc;

	if (context == NULL) {
		return 0;
	}

	tc = talloc_chunk_from_ptr(context);
	while (tc) {
		if (TC_PTR_FROM_CHUNK(tc) == ptr) return 1;
		while (tc && tc->prev) tc = tc->prev;
		if (tc) {
			tc = tc->parent;
		}
	}
	return 0;
}