util: Move ralloc to a new src/util directory.

For a long time, we've wanted a place to put utility code which isn't
directly tied to Mesa or Gallium internals.  This patch creates a new
src/util directory for exactly that purpose, and builds the contents as
libmesautil.la.

ralloc seemed like a good first candidate.  These days, it's directly
used by mesa/main, i965, i915, and r300g, so keeping it in src/glsl
didn't make much sense.

Signed-off-by: Kenneth Graunke <[email protected]>

v2 (Jason Ekstrand): More realloc uses and some scons fixes

Signed-off-by: Jason Ekstrand <[email protected]>
Reviewed-by: Marek Olšák <[email protected]>

1 files changed, 444 insertions, 0 deletions

diff --git a/src/util/ralloc.h b/src/util/ralloc.h
new file mode 100644
index 00000000000..1fe53573f0d
--- /dev/null
+++ b/src/util/ralloc.h
@@ -0,0 +1,444 @@
+/*
+ * Copyright © 2010 Intel Corporation
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the next
+ * paragraph) shall be included in all copies or substantial portions of the
+ * Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ * DEALINGS IN THE SOFTWARE.
+ */
+
+/**
+ * \file ralloc.h
+ *
+ * ralloc: a recursive memory allocator
+ *
+ * The ralloc memory allocator creates a hierarchy of allocated
+ * objects. Every allocation is in reference to some parent, and
+ * every allocated object can in turn be used as the parent of a
+ * subsequent allocation. This allows for extremely convenient
+ * discarding of an entire tree/sub-tree of allocations by calling
+ * ralloc_free on any particular object to free it and all of its
+ * children.
+ *
+ * The conceptual working of ralloc was directly inspired by Andrew
+ * Tridgell's talloc, but ralloc is an independent implementation
+ * released under the MIT license and tuned for Mesa.
+ *
+ * talloc is more sophisticated than ralloc in that it includes reference
+ * counting and useful debugging features.  However, it is released under
+ * a non-permissive open source license.
+ */
+
+#ifndef RALLOC_H
+#define RALLOC_H
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include <stddef.h>
+#include <stdarg.h>
+#include <stdbool.h>
+#include "main/compiler.h"
+
+/**
+ * \def ralloc(ctx, type)
+ * Allocate a new object chained off of the given context.
+ *
+ * This is equivalent to:
+ * \code
+ * ((type *) ralloc_size(ctx, sizeof(type))
+ * \endcode
+ */
+#define ralloc(ctx, type)  ((type *) ralloc_size(ctx, sizeof(type)))
+
+/**
+ * \def rzalloc(ctx, type)
+ * Allocate a new object out of the given context and initialize it to zero.
+ *
+ * This is equivalent to:
+ * \code
+ * ((type *) rzalloc_size(ctx, sizeof(type))
+ * \endcode
+ */
+#define rzalloc(ctx, type) ((type *) rzalloc_size(ctx, sizeof(type)))
+
+/**
+ * Allocate a new ralloc context.
+ *
+ * While any ralloc'd pointer can be used as a context, sometimes it is useful
+ * to simply allocate a context with no associated memory.
+ *
+ * It is equivalent to:
+ * \code
+ * ((type *) ralloc_size(ctx, 0)
+ * \endcode
+ */
+void *ralloc_context(const void *ctx);
+
+/**
+ * Allocate memory chained off of the given context.
+ *
+ * This is the core allocation routine which is used by all others.  It
+ * simply allocates storage for \p size bytes and returns the pointer,
+ * similar to \c malloc.
+ */
+void *ralloc_size(const void *ctx, size_t size);
+
+/**
+ * Allocate zero-initialized memory chained off of the given context.
+ *
+ * This is similar to \c calloc with a size of 1.
+ */
+void *rzalloc_size(const void *ctx, size_t size);
+
+/**
+ * Resize a piece of ralloc-managed memory, preserving data.
+ *
+ * Similar to \c realloc.  Unlike C89, passing 0 for \p size does not free the
+ * memory.  Instead, it resizes it to a 0-byte ralloc context, just like
+ * calling ralloc_size(ctx, 0).  This is different from talloc.
+ *
+ * \param ctx  The context to use for new allocation.  If \p ptr != NULL,
+ *             it must be the same as ralloc_parent(\p ptr).
+ * \param ptr  Pointer to the memory to be resized.  May be NULL.
+ * \param size The amount of memory to allocate, in bytes.
+ */
+void *reralloc_size(const void *ctx, void *ptr, size_t size);
+
+/// \defgroup array Array Allocators @{
+
+/**
+ * \def ralloc_array(ctx, type, count)
+ * Allocate an array of objects chained off the given context.
+ *
+ * Similar to \c calloc, but does not initialize the memory to zero.
+ *
+ * More than a convenience function, this also checks for integer overflow when
+ * multiplying \c sizeof(type) and \p count.  This is necessary for security.
+ *
+ * This is equivalent to:
+ * \code
+ * ((type *) ralloc_array_size(ctx, sizeof(type), count)
+ * \endcode
+ */
+#define ralloc_array(ctx, type, count) \
+   ((type *) ralloc_array_size(ctx, sizeof(type), count))
+
+/**
+ * \def rzalloc_array(ctx, type, count)
+ * Allocate a zero-initialized array chained off the given context.
+ *
+ * Similar to \c calloc.
+ *
+ * More than a convenience function, this also checks for integer overflow when
+ * multiplying \c sizeof(type) and \p count.  This is necessary for security.
+ *
+ * This is equivalent to:
+ * \code
+ * ((type *) rzalloc_array_size(ctx, sizeof(type), count)
+ * \endcode
+ */
+#define rzalloc_array(ctx, type, count) \
+   ((type *) rzalloc_array_size(ctx, sizeof(type), count))
+
+/**
+ * \def reralloc(ctx, ptr, type, count)
+ * Resize a ralloc-managed array, preserving data.
+ *
+ * Similar to \c realloc.  Unlike C89, passing 0 for \p size does not free the
+ * memory.  Instead, it resizes it to a 0-byte ralloc context, just like
+ * calling ralloc_size(ctx, 0).  This is different from talloc.
+ *
+ * More than a convenience function, this also checks for integer overflow when
+ * multiplying \c sizeof(type) and \p count.  This is necessary for security.
+ *
+ * \param ctx   The context to use for new allocation.  If \p ptr != NULL,
+ *              it must be the same as ralloc_parent(\p ptr).
+ * \param ptr   Pointer to the array to be resized.  May be NULL.
+ * \param type  The element type.
+ * \param count The number of elements to allocate.
+ */
+#define reralloc(ctx, ptr, type, count) \
+   ((type *) reralloc_array_size(ctx, ptr, sizeof(type), count))
+
+/**
+ * Allocate memory for an array chained off the given context.
+ *
+ * Similar to \c calloc, but does not initialize the memory to zero.
+ *
+ * More than a convenience function, this also checks for integer overflow when
+ * multiplying \p size and \p count.  This is necessary for security.
+ */
+void *ralloc_array_size(const void *ctx, size_t size, unsigned count);
+
+/**
+ * Allocate a zero-initialized array chained off the given context.
+ *
+ * Similar to \c calloc.
+ *
+ * More than a convenience function, this also checks for integer overflow when
+ * multiplying \p size and \p count.  This is necessary for security.
+ */
+void *rzalloc_array_size(const void *ctx, size_t size, unsigned count);
+
+/**
+ * Resize a ralloc-managed array, preserving data.
+ *
+ * Similar to \c realloc.  Unlike C89, passing 0 for \p size does not free the
+ * memory.  Instead, it resizes it to a 0-byte ralloc context, just like
+ * calling ralloc_size(ctx, 0).  This is different from talloc.
+ *
+ * More than a convenience function, this also checks for integer overflow when
+ * multiplying \c sizeof(type) and \p count.  This is necessary for security.
+ *
+ * \param ctx   The context to use for new allocation.  If \p ptr != NULL,
+ *              it must be the same as ralloc_parent(\p ptr).
+ * \param ptr   Pointer to the array to be resized.  May be NULL.
+ * \param size  The size of an individual element.
+ * \param count The number of elements to allocate.
+ *
+ * \return True unless allocation failed.
+ */
+void *reralloc_array_size(const void *ctx, void *ptr, size_t size,
+			  unsigned count);
+/// @}
+
+/**
+ * Free a piece of ralloc-managed memory.
+ *
+ * This will also free the memory of any children allocated this context.
+ */
+void ralloc_free(void *ptr);
+
+/**
+ * "Steal" memory from one context, changing it to another.
+ *
+ * This changes \p ptr's context to \p new_ctx.  This is quite useful if
+ * memory is allocated out of a temporary context.
+ */
+void ralloc_steal(const void *new_ctx, void *ptr);
+
+/**
+ * Return the given pointer's ralloc context.
+ */
+void *ralloc_parent(const void *ptr);
+
+/**
+ * Return a context whose memory will be automatically freed at program exit.
+ *
+ * The first call to this function creates a context and registers a handler
+ * to free it using \c atexit.  This may cause trouble if used in a library
+ * loaded with \c dlopen.
+ */
+void *ralloc_autofree_context(void);
+
+/**
+ * Set a callback to occur just before an object is freed.
+ */
+void ralloc_set_destructor(const void *ptr, void(*destructor)(void *));
+
+/// \defgroup array String Functions @{
+/**
+ * Duplicate a string, allocating the memory from the given context.
+ */
+char *ralloc_strdup(const void *ctx, const char *str);
+
+/**
+ * Duplicate a string, allocating the memory from the given context.
+ *
+ * Like \c strndup, at most \p n characters are copied.  If \p str is longer
+ * than \p n characters, \p n are copied, and a termining \c '\0' byte is added.
+ */
+char *ralloc_strndup(const void *ctx, const char *str, size_t n);
+
+/**
+ * Concatenate two strings, allocating the necessary space.
+ *
+ * This appends \p str to \p *dest, similar to \c strcat, using ralloc_resize
+ * to expand \p *dest to the appropriate size.  \p dest will be updated to the
+ * new pointer unless allocation fails.
+ *
+ * The result will always be null-terminated.
+ *
+ * \return True unless allocation failed.
+ */
+bool ralloc_strcat(char **dest, const char *str);
+
+/**
+ * Concatenate two strings, allocating the necessary space.
+ *
+ * This appends at most \p n bytes of \p str to \p *dest, using ralloc_resize
+ * to expand \p *dest to the appropriate size.  \p dest will be updated to the
+ * new pointer unless allocation fails.
+ *
+ * The result will always be null-terminated; \p str does not need to be null
+ * terminated if it is longer than \p n.
+ *
+ * \return True unless allocation failed.
+ */
+bool ralloc_strncat(char **dest, const char *str, size_t n);
+
+/**
+ * Print to a string.
+ *
+ * This is analogous to \c sprintf, but allocates enough space (using \p ctx
+ * as the context) for the resulting string.
+ *
+ * \return The newly allocated string.
+ */
+char *ralloc_asprintf (const void *ctx, const char *fmt, ...) PRINTFLIKE(2, 3);
+
+/**
+ * Print to a string, given a va_list.
+ *
+ * This is analogous to \c vsprintf, but allocates enough space (using \p ctx
+ * as the context) for the resulting string.
+ *
+ * \return The newly allocated string.
+ */
+char *ralloc_vasprintf(const void *ctx, const char *fmt, va_list args);
+
+/**
+ * Rewrite the tail of an existing string, starting at a given index.
+ *
+ * Overwrites the contents of *str starting at \p start with newly formatted
+ * text, including a new null-terminator.  Allocates more memory as necessary.
+ *
+ * This can be used to append formatted text when the length of the existing
+ * string is already known, saving a strlen() call.
+ *
+ * \sa ralloc_asprintf_append
+ *
+ * \param str   The string to be updated.
+ * \param start The index to start appending new data at.
+ * \param fmt   A printf-style formatting string
+ *
+ * \p str will be updated to the new pointer unless allocation fails.
+ * \p start will be increased by the length of the newly formatted text.
+ *
+ * \return True unless allocation failed.
+ */
+bool ralloc_asprintf_rewrite_tail(char **str, size_t *start,
+				  const char *fmt, ...)
+				  PRINTFLIKE(3, 4);
+
+/**
+ * Rewrite the tail of an existing string, starting at a given index.
+ *
+ * Overwrites the contents of *str starting at \p start with newly formatted
+ * text, including a new null-terminator.  Allocates more memory as necessary.
+ *
+ * This can be used to append formatted text when the length of the existing
+ * string is already known, saving a strlen() call.
+ *
+ * \sa ralloc_vasprintf_append
+ *
+ * \param str   The string to be updated.
+ * \param start The index to start appending new data at.
+ * \param fmt   A printf-style formatting string
+ * \param args  A va_list containing the data to be formatted
+ *
+ * \p str will be updated to the new pointer unless allocation fails.
+ * \p start will be increased by the length of the newly formatted text.
+ *
+ * \return True unless allocation failed.
+ */
+bool ralloc_vasprintf_rewrite_tail(char **str, size_t *start, const char *fmt,
+				   va_list args);
+
+/**
+ * Append formatted text to the supplied string.
+ *
+ * This is equivalent to
+ * \code
+ * ralloc_asprintf_rewrite_tail(str, strlen(*str), fmt, ...)
+ * \endcode
+ *
+ * \sa ralloc_asprintf
+ * \sa ralloc_asprintf_rewrite_tail
+ * \sa ralloc_strcat
+ *
+ * \p str will be updated to the new pointer unless allocation fails.
+ *
+ * \return True unless allocation failed.
+ */
+bool ralloc_asprintf_append (char **str, const char *fmt, ...)
+			     PRINTFLIKE(2, 3);
+
+/**
+ * Append formatted text to the supplied string, given a va_list.
+ *
+ * This is equivalent to
+ * \code
+ * ralloc_vasprintf_rewrite_tail(str, strlen(*str), fmt, args)
+ * \endcode
+ *
+ * \sa ralloc_vasprintf
+ * \sa ralloc_vasprintf_rewrite_tail
+ * \sa ralloc_strcat
+ *
+ * \p str will be updated to the new pointer unless allocation fails.
+ *
+ * \return True unless allocation failed.
+ */
+bool ralloc_vasprintf_append(char **str, const char *fmt, va_list args);
+/// @}
+
+#ifdef __cplusplus
+} /* end of extern "C" */
+#endif
+
+/**
+ * Declare C++ new and delete operators which use ralloc.
+ *
+ * Placing this macro in the body of a class makes it possible to do:
+ *
+ * TYPE *var = new(mem_ctx) TYPE(...);
+ * delete var;
+ *
+ * which is more idiomatic in C++ than calling ralloc.
+ */
+#define DECLARE_RALLOC_CXX_OPERATORS(TYPE)                               \
+private:                                                                 \
+   static void _ralloc_destructor(void *p)                               \
+   {                                                                     \
+      reinterpret_cast<TYPE *>(p)->~TYPE();                              \
+   }                                                                     \
+public:                                                                  \
+   static void* operator new(size_t size, void *mem_ctx)                 \
+   {                                                                     \
+      void *p = ralloc_size(mem_ctx, size);                              \
+      assert(p != NULL);                                                 \
+      if (!HAS_TRIVIAL_DESTRUCTOR(TYPE))                                 \
+         ralloc_set_destructor(p, _ralloc_destructor);                   \
+      return p;                                                          \
+   }                                                                     \
+                                                                         \
+   static void operator delete(void *p)                                  \
+   {                                                                     \
+      /* The object's destructor is guaranteed to have already been      \
+       * called by the delete operator at this point -- Make sure it's   \
+       * not called again.                                               \
+       */                                                                \
+      if (!HAS_TRIVIAL_DESTRUCTOR(TYPE))                                 \
+         ralloc_set_destructor(p, NULL);                                 \
+      ralloc_free(p);                                                    \
+   }
+
+
+#endif