First cut of ccan-izing talloc

config.h

 /* Simple config.h for gcc. */
 #define HAVE_TYPEOF 1
 #define HAVE_STATEMENT_EXPR 1
+#define HAVE_BUILTIN_EXPECT 1

talloc/TODO

+- Remove talloc.h cruft
+- Restore errno around (successful) talloc_free.

talloc/_info.c

+#include <stdio.h>
+#include <string.h>
+#include "config.h"
+
+/**
+ * talloc - tree allocator routines
+ *
+ * Talloc is a hierarchical memory pool system with destructors: you keep your
+ * objects in heirarchies reflecting their lifetime.  Every pointer returned
+ * from talloc() is itself a valid talloc context, from which other talloc()s
+ * can be attached.  This means you can do this:
+ *
+ *  struct foo *X = talloc(mem_ctx, struct foo);
+ *  X->name = talloc_strdup(X, "foo");
+ *
+ * and the pointer X->name would be a "child" of the talloc context "X" which
+ * is itself a child of mem_ctx.  So if you do talloc_free(mem_ctx) then it is
+ * all destroyed, whereas if you do talloc_free(X) then just X and X->name are
+ * destroyed, and if you do talloc_free(X->name) then just the name element of
+ * X is destroyed.
+ *
+ * If you think about this, then what this effectively gives you is an n-ary
+ * tree, where you can free any part of the tree with talloc_free().
+ *
+ * Talloc has been measured with a time overhead of around 4% over glibc
+ * malloc, and 48/80 bytes per allocation (32/64 bit).
+ *
+ * This version is based on svn://svnanon.samba.org/samba/branches/SAMBA_4_0/source/lib/talloc revision 23158.
+ *
+ * Example:
+ *	#include <stdio.h>
+ *	#include <stdarg.h>
+ *	#include <err.h>
+ *	#include "talloc/talloc.h"
+ *
+ *	// A structure containing a popened comman.
+ *	struct command
+ *	{
+ *		FILE *f;
+ *		const char *command;
+ *	};
+ *
+ *	// When struct command is freed, we also want to pclose pipe.
+ *	static int close_cmd(struct command *cmd)
+ *	{
+ *		pclose(cmd->f);
+ *		// 0 means "we succeeded, continue freeing"
+ *		return 0;
+ *	}
+ *
+ *	// This function opens a writable pipe to the given command.
+ *	struct command *open_output_cmd(const void *ctx, char *fmt, ...)
+ *	{
+ *		va_list ap;
+ *		struct command *cmd = talloc(ctx, struct command);
+ *
+ *		if (!cmd)
+ *			return NULL;
+ *
+ *		va_start(ap, fmt);
+ *		cmd->command = talloc_vasprintf(cmd, fmt, ap);
+ *		va_end(ap);
+ *		if (!cmd->command) {
+ *			talloc_free(cmd);
+ *			return NULL;
+ *		}
+ *
+ *		cmd->f = popen(cmd->command, "w");
+ *		if (!cmd->f) {
+ *			talloc_free(cmd);
+ *			return NULL;
+ *		}
+ *		talloc_set_destructor(cmd, close_cmd);
+ *		return cmd;
+ *	}
+ *
+ *	int main(int argc, char *argv[])
+ *	{
+ *		struct command *cmd;
+ *
+ *		if (argc != 2)
+ *			errx(1, "Usage: %s <command>\n");
+ *
+ *		cmd = open_output_cmd(NULL, "%s hello", argv[1]);
+ *		if (!cmd)
+ *			err(1, "Running '%s hello'", argv[1]);
+ *		fprintf(cmd->f, "This is a test\n");
+ *		talloc_free(cmd);
+ *		return 0;
+ *	}
+ */
+int main(int argc, char *argv[])
+{
+	if (argc != 2)
+		return 1;
+
+	if (strcmp(argv[1], "depends") == 0)
+		return 0;
+
+	return 1;
+}

talloc/talloc.h

+#ifndef _TALLOC_H_
+#define _TALLOC_H_
+/* 
+   Unix SMB/CIFS implementation.
+   Samba temporary memory allocation functions
+
+   Copyright (C) Andrew Tridgell 2004-2005
+   Copyright (C) Stefan Metzmacher 2006
+   
+     ** NOTE! The following LGPL license applies to the talloc
+     ** library. This does NOT imply that all of Samba is released
+     ** under the LGPL
+   
+   This library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2 of the License, or (at your option) any later version.
+
+   This library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with this library; if not, write to the Free Software
+   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+*/
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <stdarg.h>
+#include "config.h"
+
+/* this is only needed for compatibility with the old talloc */
+typedef void TALLOC_CTX;
+
+/*
+  this uses a little trick to allow __LINE__ to be stringified
+*/
+#ifndef __location__
+#define __TALLOC_STRING_LINE1__(s)    #s
+#define __TALLOC_STRING_LINE2__(s)   __TALLOC_STRING_LINE1__(s)
+#define __TALLOC_STRING_LINE3__  __TALLOC_STRING_LINE2__(__LINE__)
+#define __location__ __FILE__ ":" __TALLOC_STRING_LINE3__
+#endif
+
+#ifndef TALLOC_DEPRECATED
+#define TALLOC_DEPRECATED 0
+#endif
+
+#ifndef PRINTF_ATTRIBUTE
+#if (__GNUC__ >= 3)
+/** Use gcc attribute to check printf fns.  a1 is the 1-based index of
+ * the parameter containing the format, and a2 the index of the first
+ * argument. Note that some gcc 2.x versions don't handle this
+ * properly **/
+#define PRINTF_ATTRIBUTE(a1, a2) __attribute__ ((format (__printf__, a1, a2)))
+#else
+#define PRINTF_ATTRIBUTE(a1, a2)
+#endif
+#endif
+
+/* try to make talloc_set_destructor() and talloc_steal() type safe,
+   if we have a recent gcc */
+#if (__GNUC__ >= 3)
+#define _TALLOC_TYPEOF(ptr) __typeof__(ptr)
+#define talloc_set_destructor(ptr, function)				      \
+	do {								      \
+		int (*_talloc_destructor_fn)(_TALLOC_TYPEOF(ptr)) = (function);	      \
+		_talloc_set_destructor((ptr), (int (*)(void *))_talloc_destructor_fn); \
+	} while(0)
+/* this extremely strange macro is to avoid some braindamaged warning
+   stupidity in gcc 4.1.x */
+#define talloc_steal(ctx, ptr) ({ _TALLOC_TYPEOF(ptr) __talloc_steal_ret = (_TALLOC_TYPEOF(ptr))_talloc_steal((ctx),(ptr)); __talloc_steal_ret; })
+#else
+#define talloc_set_destructor(ptr, function) \
+	_talloc_set_destructor((ptr), (int (*)(void *))(function))
+#define _TALLOC_TYPEOF(ptr) void *
+#define talloc_steal(ctx, ptr) (_TALLOC_TYPEOF(ptr))_talloc_steal((ctx),(ptr))
+#endif
+
+#define talloc_reference(ctx, ptr) (_TALLOC_TYPEOF(ptr))_talloc_reference((ctx),(ptr))
+#define talloc_move(ctx, ptr) (_TALLOC_TYPEOF(*(ptr)))_talloc_move((ctx),(void *)(ptr))
+
+/* useful macros for creating type checked pointers */
+#define talloc(ctx, type) (type *)talloc_named_const(ctx, sizeof(type), #type)
+#define talloc_size(ctx, size) talloc_named_const(ctx, size, __location__)
+#define talloc_ptrtype(ctx, ptr) (_TALLOC_TYPEOF(ptr))talloc_size(ctx, sizeof(*(ptr)))
+
+#define talloc_new(ctx) talloc_named_const(ctx, 0, "talloc_new: " __location__)
+
+#define talloc_zero(ctx, type) (type *)_talloc_zero(ctx, sizeof(type), #type)
+#define talloc_zero_size(ctx, size) _talloc_zero(ctx, size, __location__)
+
+#define talloc_zero_array(ctx, type, count) (type *)_talloc_zero_array(ctx, sizeof(type), count, #type)
+#define talloc_array(ctx, type, count) (type *)_talloc_array(ctx, sizeof(type), count, #type)
+#define talloc_array_size(ctx, size, count) _talloc_array(ctx, size, count, __location__)
+#define talloc_array_ptrtype(ctx, ptr, count) (_TALLOC_TYPEOF(ptr))talloc_array_size(ctx, sizeof(*(ptr)), count)
+
+#define talloc_realloc(ctx, p, type, count) (type *)_talloc_realloc_array(ctx, p, sizeof(type), count, #type)
+#define talloc_realloc_size(ctx, ptr, size) _talloc_realloc(ctx, ptr, size, __location__)
+
+#define talloc_memdup(t, p, size) _talloc_memdup(t, p, size, __location__)
+
+#define talloc_set_type(ptr, type) talloc_set_name_const(ptr, #type)
+#define talloc_get_type(ptr, type) (type *)talloc_check_name(ptr, #type)
+
+#define talloc_find_parent_bytype(ptr, type) (type *)talloc_find_parent_byname(ptr, #type)
+
+#if TALLOC_DEPRECATED
+#define talloc_zero_p(ctx, type) talloc_zero(ctx, type)
+#define talloc_p(ctx, type) talloc(ctx, type)
+#define talloc_array_p(ctx, type, count) talloc_array(ctx, type, count)
+#define talloc_realloc_p(ctx, p, type, count) talloc_realloc(ctx, p, type, count)
+#define talloc_destroy(ctx) talloc_free(ctx)
+#endif
+
+/* The following definitions come from talloc.c  */
+void *_talloc(const void *context, size_t size);
+void _talloc_set_destructor(const void *ptr, int (*destructor)(void *));
+int talloc_increase_ref_count(const void *ptr);
+size_t talloc_reference_count(const void *ptr);
+void *_talloc_reference(const void *context, const void *ptr);
+int talloc_unlink(const void *context, void *ptr);
+const char *talloc_set_name(const void *ptr, const char *fmt, ...) PRINTF_ATTRIBUTE(2,3);
+void talloc_set_name_const(const void *ptr, const char *name);
+void *talloc_named(const void *context, size_t size, 
+		   const char *fmt, ...) PRINTF_ATTRIBUTE(3,4);
+void *talloc_named_const(const void *context, size_t size, const char *name);
+const char *talloc_get_name(const void *ptr);
+void *talloc_check_name(const void *ptr, const char *name);
+void *talloc_parent(const void *ptr);
+const char *talloc_parent_name(const void *ptr);
+void *talloc_init(const char *fmt, ...) PRINTF_ATTRIBUTE(1,2);
+int talloc_free(void *ptr);
+void talloc_free_children(void *ptr);
+void *_talloc_realloc(const void *context, void *ptr, size_t size, const char *name);
+void *_talloc_steal(const void *new_ctx, const void *ptr);
+void *_talloc_move(const void *new_ctx, const void *pptr);
+size_t talloc_total_size(const void *ptr);
+size_t talloc_total_blocks(const void *ptr);
+void talloc_report_depth_cb(const void *ptr, int depth, int max_depth,
+			    void (*callback)(const void *ptr,
+			  		     int depth, int max_depth,
+					     int is_ref,
+					     void *private_data),
+			    void *private_data);
+void talloc_report_depth_file(const void *ptr, int depth, int max_depth, FILE *f);
+void talloc_report_full(const void *ptr, FILE *f);
+void talloc_report(const void *ptr, FILE *f);
+void talloc_enable_null_tracking(void);
+void talloc_disable_null_tracking(void);
+void talloc_enable_leak_report(void);
+void talloc_enable_leak_report_full(void);
+void *_talloc_zero(const void *ctx, size_t size, const char *name);
+void *_talloc_memdup(const void *t, const void *p, size_t size, const char *name);
+char *talloc_strdup(const void *t, const char *p);
+char *talloc_strndup(const void *t, const char *p, size_t n);
+char *talloc_append_string(const void *t, char *orig, const char *append);
+char *talloc_vasprintf(const void *t, const char *fmt, va_list ap) PRINTF_ATTRIBUTE(2,0);
+char *talloc_vasprintf_append(char *s, const char *fmt, va_list ap) PRINTF_ATTRIBUTE(2,0);
+char *talloc_asprintf(const void *t, const char *fmt, ...) PRINTF_ATTRIBUTE(2,3);
+char *talloc_asprintf_append(char *s, const char *fmt, ...) PRINTF_ATTRIBUTE(2,3);
+void *_talloc_array(const void *ctx, size_t el_size, unsigned count, const char *name);
+void *_talloc_zero_array(const void *ctx, size_t el_size, unsigned count, const char *name);
+void *_talloc_realloc_array(const void *ctx, void *ptr, size_t el_size, unsigned count, const char *name);
+void *talloc_realloc_fn(const void *context, void *ptr, size_t size);
+void *talloc_autofree_context(void);
+size_t talloc_get_size(const void *ctx);
+void *talloc_find_parent_byname(const void *ctx, const char *name);
+void talloc_show_parents(const void *context, FILE *file);
+int talloc_is_parent(const void *context, const void *ptr);
+
+#endif